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chlorine cycle. Part 1: An energy and exergy analysis of the process
0360-3199/84 $3.00 + 0.00 Pergamon Press Ltd. International Association for Hydrogen Energy.
Int. J. Hydrogen Energy, Vol. 9, No. 6, pp. 457--472, 1984. Printed in Great Britain.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE. PART 1" AN ENERGY AND EXERGY ANALYSIS OF THE PROCESS K. F. KNOCHE and P. SCHUSTER Lehrstuhl for Technische Thermodynamik, RWTH, Aachen, Federal Republic of Germany
(Received for publication 7 June 1983) Abstraet--A vanadium/chlorine water-splitting process for the thermochemical production of hydrogen was investigated both energetically (Part 1) and experimentally (Part 2). A detailed mass and energy balance is given and discussed, starting out from the process flowsheeting developed. Balancing and optimization of the total process followed, based on experimental results from the individual reactions. The total process includes a steam power plant for producing the required electrical power. This is integrated into the thermochemical process. Results of the mass and energy balances are shown and discussed in detail. The overall efficiency of the plant is 42.5%. INTRODUCTION Thermochemical water-splitting cycles of the vanadium/chlorine family for use in hydrogen production were previously proposed in 1964 by Funk and Reinstrom [1], in 1972 by De Beni [2] and in 1978 by Behr [3]. A chemical and process engineering analysis of these proposals [4] found that in Funk's process, the hydrogen-producing reaction: 2VCI2(s) + 2HCI(G~ = 2VC13(s~ + 1HE(G) does not take place in the desired direction. This is due to the unfavourable state of equilibrium and the process should be modified as shown in Table 1. The complete process consists of five individual reactions. Compared with Funk's proposal, the hydrogen-producing step has been changed to the effect that the hydrogen is now generated by a reaction operating in aqueous hydrochloric acid solution. Vanadium(II) chlorine reacts with hydrochloric acid to form hydrogen and vanadium chloride n-hydrate. The hydration level n may be 6, 4 or 3 moles of hydrate water, depending on the conditions set for the reaction. The solid product VCI3(n) hydrate is obtained directly as a solid by the reaction. Exact conditions for the reaction
are given in Part 2. In the second reaction the vanadium(III) chloride (n) hydrate is dried. The next two steps serve to remove the chlorine. Oxygen is produced by the fifth reaction, which takes place in two stages: = ~VOC13(o~ + ½02
1200K
~VOCla~o) + 1H20 = ]VzOs(o) + 2HC1
400K
] V 2 0 5 ( L ) "~
1C12
1H20 + 1C12
= 2HC1 + 0.502
The process involves two endothermic reactions, to which high temperature heat must be supplied. In the first part of this publication, the process schemes developed are discussed and the principal results of the mass, energy and exergy balance are presented. The second part contains the results obtained from the experimental investigation of the individual reactions. PREFATORY NOTES The balancing and optimization calculations were carried out with the aid of a computer programming system [5], which had already been developed for similar process engineering plants. The aim was to establish a mass-energy and exergy balance for the
Table 1. V/C1 process, reaction scheme Temp.
(K)
Reaction 1 2 3 4 5
2VCl2ts)+ (2n HzO + 2HCI)(L) = 2(VCIs.n H20)(s) + 1H2 2(VCI3.n H20)ts) = 2VCl3ts) + 2n HzO¢G) 4VC13¢s)= 2VC12~s)+ 2VCI4(G) 2VC14~L)= 2VCI3(s/+ 1C12(G) 1C12+ 1H2Otc) = 2HC1 + ½02 Hz + ½02 Range of n: 6 > N > 2.8. * n =2.8. O v e r a l l : H20----~
457
393 433 1039 473 1200
Pressure (bar)
AHMR (MJ/kmol)
85
-45* +378* +236.5 +25.6 +60.1
1
4.5 10 1
458
K. F. KNOCHE and P. SCHUSTER 18HC( (H20) ~ - - ~ I H2
~fu ~ ~,,2j
/Xl=(n)~
[,~1._
!
...... ....
Liquid
~
Gas/liquid
I- .... _ ! ' A
I
Solid
Gas
20HCL 5.6H20
, }
p(n)'~
393K
IL2(VCE3xa.eH20
2.cL
--J'~P~K
_ _ _
2D9HCL 2 n H20 [ ] 2VCk2 +2(HCl.+nHaO) ~ [ ] 2(VCtsx nH20)+8N 2 ~
(H20) I bdr
n 2(VCL~ x oH20) + IH2 2(VCL3 x2.8H20).I.2(n_2B)H20 +8N2
[ ] 2(VCL3x2.OH20)',.2OHCL~ 2VCts+ 5.6H20+20HCL
T(n)
p(n)
(-) (K) (bar) I 6 .%33 4 363 IO 2.8 393 85
Fig. 1. Flowsheet for the H2 production, VCI3.nH20 drying stage of the process. complete process. The balancing resulted from commencing with the material data, chemical engineering flowsheets developed for the V/C1 process and with model simulations of individual plant components which are shown in detail in [4]. First of all, component areas of the overall process were balanced and approximately optimized by varying parameters. The criterion for optimization was minimization of the energy requirement for the particular area. The complete process was then assembled from the optimized parts, from which resulted some minor changes regarding the process flowsheet, caused by the conditions of the overall process. After balancing, an internal heat balance was performed, accounting for vaporizations, condensations and the heat exchange of liquid flows with a minimum temperature difference of 20K, and all other heat flows with a minimum temperature difference of 50K. All numerical values relate to a plant producing 1 kmol/s of hydrogen. MASS A N D E N E R G Y B A L A N C E H2 production and VCI3 drying This section investigates the effect of hydration level n on the energy requirements of this area of the process, where n is the hydration level of the VC13. nH20 produced during the hydrogen production stage. Reaction conditions required to give a variation in hydration level
n are known from the experimental investigation of the hydrogen-producing reaction (see Part 2). The reaction temperature and pressure are given in Fig. 1 as a function of n. The pressure p (n = 2.8) = 85 bar was extrapolated from the available measured values, taking into consideration that in the phase equilibrium calculation for the binary mixture HC1-H20, the highly concentrated hydrochloric acid supplied to the HE reaction was in the liquid phase. This extrapolation only affects the energy balance a minimal amount, due to the low dependence of the fluid enthalpy upon pressure. As can be seen from Fig. 1, dehydration of the VC13 • nH20 occurs in two stages. At the first stage, up to VCla. 2.8H20 is dried at 393K. For rapid removal of the separated crystallization water, nitrogen flows through the drier. Total dehydration of the VCI3 takes place at the second stage at a final drying temperature of 434K. In order to avoid hydrolysis of the VCla with the separated water, drying takes place in a 20 kmol/s stream of HC1 gas. The drying conditions upon which the balancing was based correlate with the experimental investigation. The hydrolysis which could possibly have occurred was neglected in calculations (see Part 2). The gaseous products from the two drying stages are partially condensed whereupon the gaseous flows are fed back to their respective drying stages, and the liquid flows to the HE reaction. The balancing results are summarized in Table 2.
Table 2. Results of the energy balance Hydration level n 6 4 2.8
Q (MW)
H2-reaction Temperature range (K)
-123.8 - 69.1 - 45.2
333-333 363-363 393-393
.VCl3-dehydration Q Temperature (MW) range (K)
(MW)
(MW)
(MW)
801.1 542.7 377.6
911.2 668.8 519.0
-905.2 -666.5 -520.0
0.0 0.1 0.5
* Q--heat; Q z,--heat requirement; Q ab--rejected heat.
333-434 363-434 393-434
~_~zu*
O ab *
Pel
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: ! The heat of hydration of the VC13 • nH20, which must be supplied for dehydration, is also taken into account in the heat requirement of the drying process (see Part 2). It can be seen from Table 2 that as hydration level n decreases, the heat required for drying reduces drastically. The heat required for drying 2.8 hydrate is only 47% of that needed for 6 hydrate. Furthermore it can be seen that the hydrogen producing reaction is an exothermic process, during which less heat is given off with decreasing hydration level. But since the temperature level of this heat energy rises with decreasing n, if a 2.8 hydrate is produced, the heat can be re-introduced into the process. It follows from these realizations that a V/C1 process should be operated with as low a VC13 • nH20 hydration level as possible. PROCESS A R E A : T H E R M A L DECOMPOSITION OF HC1 In this area of the process, the thermal decomposition of HC1 into hydrogen and chlorine takes place. Flowsheet
The process flowsheet is shown in Fig. 2. The previously described hydrogen production (Reactor 1) and the VCI3.2.8H20 drying process (Reactor 2) are shown
in the lower region of the figure. In addition, a further division of the gaseous products from the drying process is considered here. Part of the flow is separated directly by partial condensation, while the other portion is compressed in several stages before being condensed also. With this arrangement the condensation temperature of the pressurized gas is raised, which means that part of the heat given off by condensation can be used for the process. This possibility is only being considered for optimization of the total process. The dried VC13 is preheated to 800K, mixed with WE13 coming from the dechlorination process, and passed to Reactor 3. Here it disproportionates to gaseous VC14 and solid VCI2 in the temperature region 800K-1039K. The VC12 is cooled down to 393K and subsequently passed to the hydrogen reactor. Here it reacts with hydrochloric acid to form H2 and VC13.2.8H20. The gaseous VC14 is liquified, mixed with recycled VC14 from the dechlorination process and passed to Reactor 4. The thermal dechlorination of VC14takes place at 10 bar and at a reaction temperature of 473K. Reaction conditions were determined during the experimental investigation of this reaction (see Part 2). The solid formed, VCI3 is fed to the VCI3disproportionation process, while the mixture of gaseous products (VC1,/C12, 506K, 10 bar) is separated by multi-stage condensation. Pure chlorine (1 kmol/s, 356K, 1 bar) leaves the system by flowpath 79 and flows to the oxygen-producing process. I CL 2 ~ . I0 b r - ~ . - ~ 356K ( 7 9 )
F--IEI-E-~
i-
3.77VCL41
1"~1-=25 M W
LlOb--t~t--43b
--~--7
[ ~ 1 4,02H
I
~
L,2.2oL ~
I
~
1
!800K ;=
L._L__
zlvctz
.~'~LHz
~ ~
" ~ ' ~ L ' ~
~ ...... I
~
I
T43aFY~-
&6HCt
i 14,4HCl$ ( ~ I {H~O) I " ~ 2HCL
I ~".'=(e/'.J
-J 0.1VCL2
-I -/I .
, 12VCL4
,j
!
J~,=.963. I 1 1 S ~
I
I ,,J : /
..... i2L0b°r,
L_ ~ g - f f c C -~ r - - - - - " ~ ) - - -- -- "--'-"'[] [] []
Reactions : 2 V C L 2 + ( 2 H C L * 5 - 6 " 2 0 ) ~ 2(VCt3x2"SH20) + H2 2(VCt3x2.8H20)+2OHCL~ 2VCI,3~'5.6H20~'20HC{. 4VCL 3 ~ 2VCL2~-2VCL 4
--.-SoLid - GOS ------ Liquid
[]
2VCL 4
....
~
459
2VCL3, ICI.2
Fig. 2. Flowsheet for thermal HCI decomposition.
Gas/Liquid
460
K. F. KNOCHE and P. SCHUSTER
Results of the balance
PROCESS A R E A : TWO-STAGE P R O D U C T I O N OF O X Y G E N The energy required by this area of the process is influenced by the flowrate of HC1 required for VCI3 As an oxygen-producing step, the reversed Deacon drying. This influence was investigated in the calcula- reaction tions. This was necessary since the HC1 gas flowrate 1C12 + 1HzO = 2HC1 + ½Oz could not be calculated using the available measurements and literature. To do this requires knowledge of is common to nearly all proposals for thermochemical the equilibrium partial pressure of H20 vapor over water splitting cycles which used chlorine as a base. vanadium(III) chloride (n) hydrate in relation to temThis reaction was investigated in detail experiperature and n. No splitting of drying-process gaseous mentally [6]. The balancing results for this step of the products was involved. Results ot the balance are shown process (including separation of the gaseous products) in Fig. 3. are given by Eisermann [7]. The main difficulties arise The HCI flow was varied between 2 and 20 kmo~/s. in the separation of the gaseous products, whereby a It can be seen that as the HC1 flowrate rises, increases mixture of HC1, H20, C12 and 02 has to be separated. occur, both in the total heat fluxes required/rejected To achieve this requires complicated and energy conafter internal heat exchange. There are two reasons for suming processes such as absorption and rectification. this: firstly, the greater the HC1 flowrate, the more heat For the process proposed here, oxygen is produced has to be supplied to heat it up to the drying temperature in two stages according to the following scheme: of 434K; secondly, as the HC1 flowrate increases, then ~V20~(L) + 1C12 = ~VOC13(G) + ½02 so does the HC1 concentration of the gaseous products, causing a fall in the condensation temperature of the AHmR(1200K) = 37.1 MJ/kmol) HCI-H20 mixture, and consequently a devaluation of the condensation heat. For further balancing of the total ]WOCl3(o) + 1H20(G) ~V205(S) "+"2HC1 process, a HC1 flowrate of 20kmol/s was taken. (AHmR(400K) = - 6 . 9 MJ/kmol) Should a higher flowrate be necessary, extrapolation of Fig. 3 will show that the resulting heat requirement rises The advantage this proposal has over the reversed Deaonly a negligible amount in response. con step lies above all in the considerably simplified separation of product gases. =
Flowsheet
I I00
.___•--•
Heat requirement
900
"~""'~R
el ect ed hea*
70C 3~ \ ResuLting heat requirement sac
-300 o
\ AvaiLabLe
heat
PeL= O,SMW I 4
I 8
I 12
I 16
I 20
bHct(kmot/s ) Fig. 3. Effect of drying agent flowrate on heat fluxes.
Figure 4 shows the process flowsheet which serves as the basis for balancing this area of the process. The flow of chlorine entering the system by path 56 is mixed in with the recycled gas (mainly chlorine, the remainder being VOC13), preheated to a temperature of 1200K and then fed to Reactor 1. Here, the gas reacts with liquid vanadium pentoxide, which has been heated to 1200K. The flow of gaseous reaction products contains C12, VOC13 and 02. The separation of this gas mixture is achieved by multi-stage compression and condensation. During the first two condensation stages, mainly VOC13 is condensed out. The next three stages condense the chlorine at pressures of up to 60 bar. To obtain pure oxygen, the gas is cooled down to 250K during the final condensation stages, and expanded from 60 bar down to 8 bar in a turbine. The turbine outlet temperature is 189K. The gas phase now contains only minute quantities of chlorine, which are extracted by washing the gas in carbon tetrachloride. Pure oxygen leaves the system via outlet 41. The condensed chlorine is recirculated. The vanadium oxide(III) chloride which was produced is now vaporized at 400K and passed to Reactor 2. In this reactor it reacts with water steam to form vanadium pentoxide and HCI gas. Separation of the product gas is done by partial condensation. The gaseous component, consisting of 99% HC1 gas (remainder H20) is passed to the VCI3 drying process while the liquid is vaporized and recirculated.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
461
React ions:
2HCt r-] [] V205+3CL2 " 2VOCl3+1.5 02 ooo2He J ,'~ o~o.~o [ ] 2VOCL~+3H20-----V205+6HCL 295K 2.11 H~. % [-~~voc,30vereLt:3H20+3CL2 -6HC1,+1.502 -
O.2H20 I ~ 0.1 I l i C k
400K
~
IH20
Id--_.
/O
,~T~8~
-
~
I
1,4---
[~
',
) -gMW
I
I~,---
I
-2.w
Ix--l--_. J
:
lx--~.... I 25OK
SOL d Ib
ICL2 T 356K t Ib
2.03 10.5/0.01/ CLz/O2/VOCL3/
(kmot/s)
....
- -
Gas Liquid Gas/liquid
Fig. 4. Flowsheet for two-stage oxygen production.
Results o f the balance
The following is a presentation of balancing results for the most favorable flowsheet arrangement. Figure 5 shows the Q , T diagram. The resulting heat requirement is covered by the H T R process heat between 820K and 1300K. A t temperatures below 950K the temper400 --
Heal
Table 3. Comparison of two-stage oxygen production with the reversed Deacon step Heat flows (MW) Total heat requirement Total rejected heat After internal heat exchange: Heat requirement (HR) Available heat Electric power (EP) Total energy requirement (TER)*
requirernent-~in/h:aetrna t
~
300
xchange
O2-generator Two-step cycle Reversed Deacon 366 -297
588 -510
135 - 67 31.6
375 -298 -4
225
364
* TER = HR + 1/rTel"EP (with r/e=-~ 35%). '(-Rejected heo~c
ature difference for the transfer of heat from high temperature heat to the heat-demand curve becomes very large ( A T ~ 300K-500K). For the total process the matching becomes more favorable. Table 3 shows the most important balancing results---results for two-stage oxygen production are set against those obtained by Eisermann for the reversed Deacon reaction. It arises from this comparison that two-stage oxygen production requires considerably less energy. Moreover exergy losses from the two-stage process are lower, since the heat fluxes exchanged are considerably lower.
200 ,~./f/ I/// I00
Resulting heal requirem~n~c' "~
I ,,AvaiLabLe heat
/
J 300
500
700
900
I I00
I ~k~O
1400
T (K) Fig. 5. Heat flux/temperature diagram for two-stage production of oxygen.
THE T O T A L PROCESS Process flowsheet
The flowsheet of the complete process is put together
462
K. F. KNOCHE and P. SCHUSTER
from the 'thermal HC1 decomposition' (see Fig. 2) and the 'two-stage 02 production' (see Fig. 4) areas of the process. The same applies for the computational flow sheets (see Appendix). There is a steam power plant integrated into the total process (see Fig. 2) which is required to: (a) provide the required electrical power for the total process, and (b) improve the heat balance of the total process by supplying heat from the condensor to the VC13 drying process. To enable this, the steam power plant uses a backpressure turbine (turbine outlet pressure 8bar). The heat of condensation is then given off at a temperature of 443K. The state of live steam is fixed at 230 bar, 818K.
I$Ot"
I00(
50C
Balancing results It can be seen from the heat flux/temperature diagram for O2 production (see Fig. 5) that a heat supply of around 60 MW (vaporization heat for the VOC13, C12 mixture) is needed in the temperature range 350K400K. This cannot be balanced out internally by the total process. Since the condensation heat of the steam power plant is needed, a surplus of electrical power is generated by it. It was attempted to reduce the heat r(K) demands of the thermochemical process by utilizing this surplus electrical power. The process previously shown Fig. 6. Heat flux/temperature diagram for the total process. and described in Fig. 2 lent itself to this purpose, that is, the division and compression of gaseous products from the VC13 drying process. A rise in the condensation temperature of the HCI/H20 mixture is achieved, thereby enabling partial utilization of the condensation heat flux within the process. Table 4. Summary of the most important balancing results for The following presents the balancing results for the the total process overall process, for the case where 20% of the VC13 drying gaseous products are compressed to 5.5 bar. Heat (MW) Detailed results of the mass and energy balance for the total process are given in the Appendix. The heat Total heat requirement 1457.1 flux/temperature diagram for the total process is shown Total rejected heat 1239.9 in Fig. 6. Table 4 contains a summary of important Heat steam power plant 316.0 results from the balancing. It can be seen from the heat Heat thermochemical process + 390.0 flux/temperature diagram that after internal heat exchange, process heat must be supplied to the steam After internal heat exchange: 706.0 boiler and the high temperature reactions (WE13 disheat requirement proportionation and chlorination of vanadium pentoxRejected heat 412.8 ide). Ideally, the resulting heat requirement of the total Internal heat exchange 827.1 process (706 MW) is covered by HTR heat, the helium Required electric power: steam power plant 3.8 temperature of which changes from 1300K at inlet to Thermochemical process + 69.1 660K at outlet. Balancing the electrical power (see Table 4) leaves 72.9 a surplus of around 7.2 MW which is available to drive ancillary machinery and cover friction losses. These Produced eleetric power - 80.1 have not been considered up to now. If the HTR heat Thermal efficiency (%) 40.5 obtained is compared with the calorific value of the H2 Thermal efficiency* (%) 42.5 produced, a plant efficiency of 40.5 or 42.5% (see Table 4) is obtained. Exergy losses from the complete plant * Internal heat balance with a minimum temperature difare 245 MW, distributed over the individual process ference of 12K for vaporizations, condensations and the heat areas as shown in Fig. 7. exchange of liquid flows.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
~'vJ
y----~ x too (%)
0
I0
Hz-generation and drying
F
Steam power-pLarR
~ 1 8 . 1
Reactions of O2-generation
~
20
Dechtor ination
40
50
,o,
computational reasons. Tables A1 and A3 contain the results of the mass balance, while the energy balance is shown in Tables A2 and A4. The abbreviations written into the blocks of the computer flowsheets (Figs A1 and A2) and in the Tables A2 and A4 have the following meanings:
Reactors
6.5
VCL~-disproportionat ion ~"~ 6 I Compressors and pumps
30
463
Tu =300K
] 3.9 1.1
GLEI GENE GQPF
Remaining heat exchange ~ 9 . 2
Fig. 7. Relative exergy losses from individual plant components and process areas. The greatest irreversibilities occur in the H2 production and VCI3 drying (including gaseous product separation) areas of the process, which account for 55 % of the total exergy loss. In addition, exergy losses from the steam p o w e r plant (18.1%) and from the VC13 disproportionation and O2-producing reactions (each around 6%) are also significant.
No performs the mass balance at a given reaction temperature and pressure No performs the mass balance at adiabatic reaction temperature (iterative process) No performs the mass balance at given temperature steps (adiabatic reaction temperature up to the given reactor outlet temperature = heat profile of the reator) No signifies a special reactor 09 VOC13 hydrolysis reaction 10 V205 chlorination 12 VC13 disproportionation 13 H2 producing reaction 14 VC14 dechlorination Drying VC13 dehydration
Separators REFERENCES 1. J. E. Funk and R. N. Reinstrom, System study of hydrogen generation by thermal energy, Allison Division of General Motors, EDR 3714, Vol. 11, supplement A (1964). 2. G. De Beni, Euratom Staff, Hydrogen production from water using nuclear heat, Progress Report No. 3, EUR 5059e (1974). 3. F. Behr, Personal communication, Lehrstuhl fiir Reaktortechnik, RWTH Aachen, published in 4. 4. P. Schuster, Experimentelle unteruschung und Bilanzierung von Vanadium/Chlor- und Vanadium/Brom-Mehrstufenprozessen zur thermochemischen Erzeugung von Wasserstoff, Ph.D. thesis, Aachen (1980). 5. K. T. Knoche, H. Cremer and W. Eisermann, Balance and optimisation procedure for thermochemical cycles for hydrogen production, First World Hydrogen Conference, Miami (1975). 6. H. Cremer, D. Breywisch, S. Hegels, W. Schneider, P. Schuster, G. Steinborn, G. Wozny and G. Wiister, Entwicklung von Mehrstufenprozessen zur Wasserstofferzeugung mit Hilfe von Kernw~irme, Final Report Project, ET 4031A, German Ministry for Research and Technology (1978). 7. W. Eisermann, Bilanzierung von Eisen-Chlorprozessen zur Thermischen Wasserzersetzung, Ph.D. thesis, Aachen (1977). APPENDIX This appendix contains the full set of results for the mass and energy balance, together with the necessary explanatory notes on the computational flowsheets. To carry out the balancing by computer, the process flowsheets (see Figs 2 and 4) were translated into computer code (see Figs A1 and A2). This coding is used on the computational flowsheets, which in some places are more detailed than the process flowsheets, for
SEPARA separation of a multi-phase input flow into gas and liquid/solid phases according to the phase equilibrium TRENNE high purification
General apparatus MIXCHE mixing of up to five input flows; evaluation of the adiabatic mixture temperature HEATER exchange of heat until a given outlet temperature is reached and the determination of a heat profile in relation to temperature PUMPVD/ pump, compressor/turbine; changTURBIN ing the pressure to a given outlet pressure; evaluation of electrical power for a given isentropic efficiency (compressor = 0.9; turbine = 0.85); evaluation of the adabatic outlet temperature DROSSE adiabatic throttling SPLIT No division of an inlet flow into two separate flows HOLDUP definition of the mass flow of a particular component in a mixture
Apparatus for regulation and control MESSEN) . . . . REGEL No] serve to transmit mtormatxon to RETEMpJOther parts of the plant
HCLH20
VCl 2
'I O2-generation
I ~from
HCI
VCL2
VCL3xnH20 VCL2
, HCL(H ) ) ~
(~
I I
)
H 2
_
HCL.H20
_
PUMP VD
HCL, H20
"fCl. H20
I
I
I I
i
Fig. A1. Computer flowsheet for the thermal HCI decomposition.
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VCI
VCI4 CL2
©
PUMP VD
VCL4 Ct2
CL2 VCL4
Lzto
~2-generation
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K . F . KNOCHE and P. SCHUSTER Table A1. Composition/mass flows of streams for the thermal/HC! decomposition (compare with Figs A1 and 2)
Stream No.
Unit From To
H2
H20
HCI 16.07547 1.67591 1.67591 2.09489
1 2 3 4
15 1 2 5
1 2 3 6
4.48623 4.47183 4.47183 5.58979
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
0 6 0 7 7 18 17 8 9 9 9 10 11 29 11 13 14 14 12 13 20 0 19 0 16 1 49 0 48 35 32 30 35 40 41 42 43 44 45 0 50 51 52 51 52 52 53 54 55 56 55 58 58 57 61 60
6 7 7 0 8 11 18 9 7 10 0 11 29 30 12 14 15 15 13 20 21 19 17 18 17 16 9 49 49 47 35 31 40 41 42 43 44 45 50 51 51 0 51 52 54 53 30 55 56 58 64 64 62 59 57 61
5.58979 5.58979
5.58979 0.01800 0.01800 5.58979
kmol/s CIE VCh
VCI2
VCl3
HH20
2.09489 1.99994 1.99995 2.09489 19.99945 19.99939 2.09489
1.00000 0.09489
0.09935
2.00000
5.58979
0.09489
0.09935 0.09935 0.09935
2.00000 2.00000 2.00000
5.58979
1.00000
5.50779 4.48623
20.09434 16.07547
4.48623 5.60779 1.12156 1.12156
16.07547 20.09434 4.01887 4.01887 1.99994 1.99994 19.99945 14.39956 14.39956
0.01440 0.01440
2.09936 2.09936 2.09935
0.09935
4.00000
2.00000 3.77359 2.00000 0.00000 0.32070 3.77359 1.32070 1.77359 0.32070
2.00000 2.00000 1.32070 1.00919 1.00919 0.31151 0.00300 1.00619 1.00000 1.00000 1.00000
1.77359 0.04593 0.04593 1.72765 0.01346 0.03247
T (K)
P (bar)
280 280 281 393
1.00 1.00 1.00 85.00
393 393 393 393 393 434 434 393 393 393 393 393 434 510 434 363 280 363 363 363 479 293 434 434 434 280 393 393 393 961 800 510 961 430 463 455 450 450 473 473 470 473 473 470 506 506 510 400 400 390 400 390 390 356 355 370
85.00 85.00 85.00 85.00 85.00 1.00 1.00 85.00 85.00 85.00 85.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.30 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.00 2.00 2.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 1.00 10.00 10.00 10.00 10.00 10.00 10.00 1.00 1.00 10.00
(connnued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
467
Table Al.---continued. Stream No. 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94
Unit From To 60 62 64 65 8 8 47 46 31 32 33 34 34 36 37 38 39 63 59 63 21 22 23 24 24 25 26 26 4 27 28 3 8 8
H2
64 63 65 50 14 1 48 47 32 33 34 46 36 37 38 39 50 60 0 64 22 23 24 25 25 26 27 3 5 28 17 4 24 26
H20
kmol/s C12 VCI4
HC1
VCl2
WE13
HH20
0.01511 1.00619 0.03247 0.32070 1.77359 0.32070 1.77359 5.58979 5.58979
2.09489 2.09489 2.09935 2.09935 0.09935 0.09935 0.09935 2.09935
4.00000 4.00000 4.00000
2.00000 2.00000 2.00000 2.00000 2.00000 1.00000 0.01511 1.00000 0.00619 0.01736 1.12156 1.12156 1.12156
4.01887 4.01887 4.01887
1.12156 1.12156 0.00360 1.11796 5.58979 0.00360 0.00360 5.58979 5.58979 5.58979
4.01887 4.01887 3.59989 0.41898 2.09489 3.59989 3.59989 2.09489 2.09489 2.09489
T (K)
P (bar)
370 370 399 473 393 393 961 961 800 800 800 1040 1040 495 473 473 473 370 356 370 379 506 400 322 400 322 322 322 286 314 434 285 393 393
10.00 10.00 10.00 10.00 85.00 85.00 1.00 1.00 1.00 1.00 1.00 4.50 4.50 4.50 4.50 10.00 i0.00 10.00 1.00 10.00 2.30 5.50 5.50 5.50 5.50 5.50 5.50 5.50 85.00 1.00 1.00 1.00 85.00 85.00
Table A2. Composition/mass flows of streams for the two-stage production of oxygen (compare with Figs A2 and 4) Strea:~ No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Unit From To 53 1 2 2 3 4 5 6 7 8 9 10 11 12
1 2 3 0 4 72 57 7 8 9 10 11 12 13
kmol/s 0 2
H20
HCI
C12
VOC13
V205 0.33333 0.33333
0.50000
2.34644
0.70774
0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
2.34644 2.34644 2.34644 2.05003 2.05003 2.02146 2.02146 2.02146 0.52725 0.52725
0.70774 0.70774 0.70774 0.01334 0.01334 0.00219 0.00219 0.00219 0.00000 0.000130
T (K)
P (bar)
400 1200 1200 1200 410 497 293 381 293 293 370 293 293 373
1.00 1.00 1.00 1.00 1.00 2.50 2.50 6.00 6.00 6.00 13.00 13.00 13.00 28.00
(conanued)
468
K . F . KNOCHE and P. SCHUSTER Table A2..---con~nued. Stream No.
Unit From To
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
13 11 15 16 14 21 22 14 17 18 19 20 23 28 23 24 25 26 27 29 29 30 32 33 34 30 31 35 8 36 37 38 37 40 39 39 41 42 42 43 44 0 46 45 47 48 0 47 2 49 50 0 51 51 65 52 53 68 69 55 53
14 56 16 20 21 22 23 17 18 19 20 27 64 29 24 25 26 27 35 30 32 32 33 34 35 31 0 44 36 37 38 63 40 61 42 41 43 43 49 44 45 46 45 47 48 2 47 0 47 71 51 51 0 53 52 53 66 0 55 70 51
kmo~s 02
H20
HCI
0.50000
0.50000 0.50000 0.50000
0.50000 0.50000
0.50000
C12
VOC13
0.52725 1.49421 1.49421 1.49421 0.15670 0.15670 0.15670 0.37054 0.37054 0.37054 0.37054 1.86475 0.06263 0.06263 0.09408 0.09408 0.09408 0.09408 1.95883 0.00365 0.05898 0.00365 0.06263 0.06263 0.06263
0.00000 0.00219 0.00219 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
2.02146 0.02857 0.02857 0.02057 0.02057 0.00800 0.00800 0.02607 0.19820 0.29892 0.02607
0.00219 0.01115 0.01115 0.01114 0.01114 0.00000 0.00000 0.66683 0.03809 0.03371
V205
0.50000 0.50000
0.32499 2.34644 1.00000 1.00000 3.34644 3.34519 3.34644 14.00000 14.00126
0.66683 0.03871 0.04090
0.04090 0.04090 0.04107 -0.00251
0.20000
0.10713
0.20000 1.00158 1.00158 0.20158 0.00158 0.20001 0.20001
0.10713 2.10713 1.99982 0.10732 0.10732
0.66683 0.79019 2.00000 2.00028 0.78991 0.12324 0.12324 0.12324 0.00060
T (K) 293 293 239 343 293 376 293 293 293 239 343 343 293 189 293 293 239 343 343 189 189 189 189 189 343 189 298 343 293 249 249 343 249 343 343 343 343 343 343 343 343 356 343 343 343 1200 343 343 1200 400 400 400 400 400 283 400 400 293 293 400 400
P (bar) 28.00 13.00 1.00 1.00 28.00 60.00 60.00 28.00 28.00 1.00 1.00 1.00 60.00 8.00 60.00 60.00 1.00 1.00 1.00 8.00 8.00 8.00 60.00 1.00 1.00 8.00 8.00 1.00 6.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
(continued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1 Table A2.---continued. Stream No. 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
Unit From To 56 57 57 58 59 60 61 59 62 63 64 0 0 65 66 67 67 54 54 68 0 70 71 0 72
15 6 58 59 60 61 41 62 63 39 28 65 65 0 67 54 69 68 69 65 70 50 50 71 5
kmol/s 02
H20
HCI
0.50000
0.50000 1.00000 1.02026 1.01868 0.20158 0.00158 0.20001 0.00158
Clz
VOCI3
1.49421 2.05003 0.29641 0.29641 0.09271 0.09271 0.10071 0.20370 0.20370 0.22427 0.06253
0.00219 0.01334 0.69440 0.69440 0.00062 0.00062 0.00062 0.69378 0.69378 0.70492 0.00000
2.10713 1.99982 0.10732 1.99982
V2Os
0.12324 0.01004 0.11321 0.01004
0.00158 0.20000 0.20000
1.99982 0.10732
0.50000
2.34644
0.12324 0.66666 0.66666 0.70774
T (K)
P (bar)
293 293 293 279 279 343 343 279 343 343 250 283 283 283 293 293 293 293 293 293 400 400 400 400 370
13.00 2.50 2.50 1.00 1.00 1.00 1.00 1,00 1.00 1.00 60.00 1.00 1,00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.50
Table A3. Energy balances of units for the thermal HCI decomposition (compare with Figs A1 and 2) Unit No.
Unit Name
1
REGEL4
2 3
MIXCHE
4 5 6 7
PUMPE1
PUMPE1 HEATER HOLDUP REGEL3
9
MESSEN GLEI13
10 11
HEATER DRYING
12 13
HEATER SPLIT0
14 15 16 17
RETEMP HEATER HEATER MIXCHE
8
Enthalpy (MW) in out -2869.1 0.0 - 1526.7 -1526.4 -378.1 -1904.5 -1906.0 -1855.8 -1855.8 -183.0 -1855.8 -1855.8 -952.1 -2855.9 -1773.3 -2856.3 -3111.4 -3166.7 0,0 -2533.3 -2533.3 -1341.6 -176.9 -1277.1 -319.3
-1526.7 -1341.6 - 1526.4 -1904.5 0.0 1906.0 1855.8 -1855.8 -183.0 -1855.8 1855.8 -2855.9 2.7 -2856.3 -1140.5 -3111.4 -3166.7 -2533.3 -633,3 -2533,3 -2869.1 -1277.1 -1773.3 0.0 0.0
Entropy (MW/K) in out 3.080 0.000 0.413 0.413 0.108 0.522 0.514 0.749 0.749 0.317 0,749 0.749 0.247 0.500 3.962 0.504 5.219 5.080 0.000 4.064 4.064 2.670 0.396 2.853 0.713
0.413 2.670 0.413 0.522 0.000 0.514 0.749 0.749 0.317 0.749 0.749 0.500 0.102 0.504 0.347 5.219 5.080 4.064 1.016 4.064 3.080 2.853 3.962 0.000 0.000
Q (MW)
Temp range (K-K)
P(EL) (MW)
AD
0.0
AD AD
0.2 0.0
-1.7 50.2 AD AD
286 286
286 393
AD -45.2
393
393
0.0 0.0
AD 377.6
393
434
0.0 0.0
434
363
363 280
280 434
-55.2 AD AD -335.7 64.6 AD
0.2 0.0 0.0 0.0
0.0 0.0 0,0 0.0 0.0 0.0
(continued)
469
470
K. F. KNOCHE and P. SCHUSTER Table A3.--continued.
Unit No.
Unit Name
18 19 20 21 22 23 24 25 26
HOLDUP HEATER PUMPVD HEATER PUMPVD HEATER RETEMP HEATER REGEL4
27 28 29 30
DROSSE HEATER HEATER MIXCHE
31 32
HEATER SPLIT
33 34
HEATER GQPF12
35
GQPF12
36 37 38 39 40 41 42 43 44 45 46 47
HEATER HEATER PUMPVD HEATER HEATER PUMPVD HEATER HEATER PUMPVD HEATER HEATER MIXCHE
48 49 50
HEATER HOLDUP MIXCHE
51
REGEL2
52
GQPF14
53 54 55
HEATER HEATER SEPARA
56 57 58
HEATER HEATER SEPARA
59 60
HEATER TRENNE
61 62 63
DROSSE HEATER SEPARA
Enthalpy (MW) in out -1773.3 -185.1 -633.3 -615.4 -631.1 -611.7 -628.4 -528.4 -709.9 0.0 -331.8 -331.8 -1140.5 -1124.6 -1080.4 -2205.1 -2080.7 0.0 -2080.7 -2080.7 0.0 0.0 0.0 -898.1 -1009.5 -1083.8 -1083.8 0.0 0.0 0.0 0.0 0.0 0.0 -844.0 0.0 -857.8 -857.8 -952.1 0.0 -949.3 -1083.8 -1083.8 -2033.1 -2033.1 0.0 -1081.2 -883.8 -979.9 0.0 -20.5 1.9 -21.5 0.0 1.9 -5.9 0.0 1.9 -14.0 -15.7 0.0
1773.3 175.9 -615.4 -631.1 -611.7 -628.4 -628.4 -709.9 -331.8 -378.1 -331.8 -319.3 -1124.6 -2205.1 0.0 -2080.7 0.0 -2080.7 -2080.7 -844.0 -898.1 0.0 0.0 -1009.5 -1083.8 1083.8 1083.8 0.000 0.0 0.0 0.0 0.0 0.0 -857.8 -857.8 0.0 -952.1 -952.1 -2033.1 0.0 0.0 -1083.8 -2033.1 -883.8 1081.2 -1080.4 -979.9 -20.5 -959.3 -21.5 1.9 -7.5 - 14.0 3.5 1.9 -8.4 1.9 -15.7 -5.9 -9.8
Entropy (MW/K) in out 3.962 0.373 1.016 1.024 0.987 0.995 0.958 0.958 0.739 0.000 0.630 0.679 0.347 0.381 0.367 0.748 0.941 0.000 0.941 0.941 0.000 0.000 0.000 0.895 0.744 0.593 0.593 0.000 0.000 0.000 0.000 0.000 0.000 0.408 0.000 0.394 0.394 0.247 0.000 0.620 0.593 0.593 1.214 1.214 0.000 0.366 0.963 0.756 0.000 0.233 0.229 0.230 0.000 0.229 0.216 0.000 0.210 0.226 0.222 0.000
3.962 0.396 1.024 0.987 0.995 0.958 0.958 0.739 0.630 0.108 0.679 0.713 0.381 0.748 0.000 0.941 0.000 0.941 0.941 0.408 0.895 0.000 0.000 0.744 0.593 0.593 0.593 0.000 0.000 0.000 0.000 0.000 0.000 0.394 0.394 0.000 0.247 0.247 1.214 0.000 0.000 0.593 1.214 0.963 0.366 0.367 0.756 0.233 0.524 0.230 0.229 0.004 0.226 0.233 0.210 0.004 0.229 0.222 0.216 0.006
Q (MW) AD 8.2 AD -15.7 AD -16.7 AD -81.6 AD AD 12.6 15.9 AD 124.4 AD AD 338.6
Temp range (K-K)
P(EL) (MW) 0.0 0.0 17.9 0.0 19.4 0.0 0.0 0.0 0.0
293
434
479
379
506
400
400
322
314 434
434 510
510
800
800
1040
0.0 0.0 0.0 0.0 0.0 0.0
AD
0.0 0.0 0.0
-111.3 -74.3 AD AD AD AD AD AD AD AD -13.8 AD
1040 495
495 473
1040
961
-94.4 AD AD
961
393
AD
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0
68.1
473
506
0.0
AD -96.1 AD
506
400
0.0 0.0 0.0
-1.0 AD AD
400
390
0.0 0.0 0.0
1.6 AD
356
400
0.0 0.0
390
370
AD -1.7 AD
0.0 0.0 0.0
(continued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1 Table A3.--continued. Unit No.
Unit Name
64
MIXCHE
65
HEATER
Enthalpy (MW) in out -959.3 -7.5 -8.4 -9.8 -985.1
-985.1 0.0 0.0 0.0 -949.3
Entropy (MW/K) in out 0.524 0.004 0.004 0.006 0.537
0.537 0.000 0.000 0.000 0.620
Q (MW)
Temp range (K-K)
P(EL) (MW)
AD
35.7
0.0
399
473
0.0
AD = adiabatic. P(EL) = electrical power.
Table A4. Energy balances for the two-stage production of oxygen (compare with Figs A2 and 5) Unit No.
Unit name
1 2
HEATER GQPF10
3 4 5 6 7 8
HEATER PUMPVD HEATER PUMPVD HEATER SEPARA
9 10 11
PUMPVD HEATER SEPARA
12 13 14
PUMPVD HEATER SEPARA
15 16 17 18 19 20
DROSSE HEATER TURBIN DROSSE HEATER MIXCHE
21 22 23
PUMPVD HEATER SEPARA
24 25 26 27
TURBIN DROSSE HEATER MIXCHE
28 29
TURBIN SEPARA
30
TRENNE
31 32
HEATER MIXCHE
33
DROSSE
Enthalpy (MW) in out -514.7 -446.0 85.5 -323.4 -463.6 -476.0 -9.9 -2.4 -11.4 0.0 -2.9 3.4 -30.1 0.0 0.5 2.0 -7.2 0.0 -29.6 -29.6 -7.0 -7.0 -7.0 0.7 0.5 -0.2 1.5 -1.9 0.0 -1.8 -1.8 -1.8 1.3 0.1 -1.8 -3.1 0.0 -1.5 0.0 -1.5 -1.5 -0.1 - 1.6
-445.0 -323.4 0.0 -463.6 -448.7 -516.1 -2.4 -11.4 -2.9 -8.6 3.4 -30.1 -0.5 -29.6 2.0 -7.2 -0.2 -7.0 -29.6 0.7 -7.0 -7.0 0.5 1.3 0.0 1.5 -1.9 -0.1 -1.8 -1.8 -1.8 0.1 1.4 0.0 -3.1 -1.5 -1.5 -0.1 -1.5 -0.0 -1.6 0.0 - 1.6
Entropy (MW/K) in out 0.058 0.144 0.936 1.121 0.931 0.871 0.554 0.558 0.530 0.000 0.524 0.527 0.410 0.000 0.203 0.204 0.171 0.000 0.203 0.218 0.049 0.049 0.054 0.341 0.084 0.122 0.123 0.111 0.000 0.012 0.012 0.014 0.426 0.021 0.091 0.093 0.000 0.089 0.000 0.088 0.004 0.000 0.004
0.144 1.121 0.000 0.931 0.937 0.750 0.553 0.530 0.524 0.007 0.527 0.410 0.203 0.203 0.204 0.171 0.122 0.049 0.218 0.341 0.049 0.054 0.084 0.426 0.000 0.123 0.111 0.099 0.012 0.012 0.014 0.021 0.447 0.000 0.093 0.089 0.004 0.000 0.088 0.094 0.004 0.000 0.006
Q (MW)
Temp range (K-K)
P(EL) (MW)
68.8 37.1
400 1070
1200 1200
0.0 0.0
-140.3 AD -40.1 AD -9.0 AD
1200
410
370
293
381
293
0.0 15.0 0.0 7.5 0.0 0.0
AD -33.5 AD
370
293
6.2 0.0 0.0
AD -9.2 AD
373
293
2.5 0.0 0.0
239
343
239
343
376
293
AD 30.3 AD AD 7.5 AD AD -3.4 AD AD AD 1.9 AD
239
343
0.0 0.0 0.0 0.0 0.0 0.0 1.7 0.0 0.0 -0.0 0.0 0.0 0.0
AD AD
-1.3 0.0
AD
0.0
1.5 AD AD
189
298
0.0 0.0
0.0 (continued)
471
472
K. F. KNOCHE and P. SCHUSTER Table A4.---continued. Unit No.
Unit name
34 35
HEATER MIXCHE
36 37
DROSSE SEPARA
38 39
HEATER SEPARA
40 41
HEATER MIXCHE
42
TRENNE
43
MIXCHE
44
MIXCHE
45
MIXCHE
46 47
HEATER REGEL1
48 49 50
HEATER HEATER MIXCHE
51
REGEL3
52 53
HEATER GENE09
54
TRENNE
55 56 57
HEATER TURBIN SEPARA
58 59
DROSSE SEPARA
60 61
HEATER MIXCHE
62 63
HEATER MIXCHE
64 65
HEATER REGEL4
66 67
HEATER SEPARA
68 69
MESSEN MIXCHE
70 71 72
HOLDUP HOLDUP HEATER
Enthalpy (MW) in out -1.6 1.4 0.1 -8.6 -8.6 0.0 -8.6 -501.6 0.0 -0.0 -25.5 -0.3 -476.1 0.0 -25.8 0.0 1.5 -25.7 -24.2 1.5 1.5 -22.8 20.5 -22.8 -475.7 -140.2 -447.5 -587.8 -1342.6 -238.1 -587.6 -239.6 - 192.3 0.0 -160.3 -29.6 -516.1 0.0 -506.2 -506.1 0.0 -0.5 0.0 -0.3 -505.7 -7.8 -493.8 -0.1 -287.7 -293.5 -319.4 -345.3 0.0 -185.5 - 153.0 -7.2 -140.2 -447.5 -448.7
AD = adiabatic. P(EL) = electrical power.
0.1 1.5 0.0 -8.6 -8.6 -0.0 -7.8 -475.1 -25.5 0.0 -25.8 0.0 0.0 -475.7 -25.7 0.0 -24.2 0.0 -22.8 0.0 1.5 -22.3 20.6 85.5 -447.6 -587.7 0.0 -1342.8 -587.7 -239.6 -514.7 -319.4 - 185 -7.2 - 140.2 -29.6 -9.9 -506.2 -505.1 -0.5 -505.7 -0.3 -0.3 0.0 -493.8 -501.6 0.0 -1.8 -288.1 -293.0 -345.3 -192.3 -153.0 -185.5 - 160.3 0.0 -140.2 -447.5 -475.0
Entropy (MW/K) in out 0.006 0.447 0.014 0.007 0.007 0.000 0.005 0.224 0.000 0.002 0.059 0.023 0.165 0.000 0.082 0.006 0.462 0.088 0.550 0.228 0.228 0.778 3.190 0.778 0.161 0.107 0.232 0.343 0.690 0.066 0.343 0.199 0.377 0.000 0.047 0.208 0.750 0.000 0.196 0.197 0.000 0.021 0.002 0.021 0.177 0.008 0.216 0.099 0.066 0.067 0.505 0.422 0.000 0.373 0.045 0.002 0.107 0.232 0.937
0.014 0.462 0.000 0.007 0.005 0.002 0.008 0.165 0.059 0.002 0.082 0.000 0.006 0.161 0.088 0.000 0.550 0.000 0.778 0.000 0.228 0.778 3.190 0.936 0.232 0.343 0.000 0.696 0.343 0.199 0.058 0.505 0.373 0.002 0.107 0.208 0.554 0.196 0.197 0.021 0.177 0.021 0.023 0.000 0.216 0.224 0.000 0.091 0.066 0.067 0.422 0.377 0.045 0.373 0.047 0.000 0.107 0.232 0.871
Q (MW) 1.7 AD
Temp range (K-K) 189
343
P(EL) (MW) 0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
AD
0.0
AD
0.0
AD
0.0
AD
0.0
AD AD
0.0 0.0
108.3 28.1 AD
343 343
1200 400
AD 48.5 -6.9
0.0 283 400
400 400
AD 20.1 AD AD
0.0 0.0 0.0
0.0 0.0 0.0
293
400
0.0 0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
11.9 AD
279
343
0.0 0.0
-1.7 AD
293
250
0.0 0.0
-26.0 AD
400
293
0.0 0.0
AD AD
0.0 0.0
AD AD -27.4
0.0 0.0 0.0
497
370
Int. J. Hydrogen Energy, Vol. 9, No. 6, pp. 457--472, 1984. Printed in Great Britain.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE. PART 1" AN ENERGY AND EXERGY ANALYSIS OF THE PROCESS K. F. KNOCHE and P. SCHUSTER Lehrstuhl for Technische Thermodynamik, RWTH, Aachen, Federal Republic of Germany
(Received for publication 7 June 1983) Abstraet--A vanadium/chlorine water-splitting process for the thermochemical production of hydrogen was investigated both energetically (Part 1) and experimentally (Part 2). A detailed mass and energy balance is given and discussed, starting out from the process flowsheeting developed. Balancing and optimization of the total process followed, based on experimental results from the individual reactions. The total process includes a steam power plant for producing the required electrical power. This is integrated into the thermochemical process. Results of the mass and energy balances are shown and discussed in detail. The overall efficiency of the plant is 42.5%. INTRODUCTION Thermochemical water-splitting cycles of the vanadium/chlorine family for use in hydrogen production were previously proposed in 1964 by Funk and Reinstrom [1], in 1972 by De Beni [2] and in 1978 by Behr [3]. A chemical and process engineering analysis of these proposals [4] found that in Funk's process, the hydrogen-producing reaction: 2VCI2(s) + 2HCI(G~ = 2VC13(s~ + 1HE(G) does not take place in the desired direction. This is due to the unfavourable state of equilibrium and the process should be modified as shown in Table 1. The complete process consists of five individual reactions. Compared with Funk's proposal, the hydrogen-producing step has been changed to the effect that the hydrogen is now generated by a reaction operating in aqueous hydrochloric acid solution. Vanadium(II) chlorine reacts with hydrochloric acid to form hydrogen and vanadium chloride n-hydrate. The hydration level n may be 6, 4 or 3 moles of hydrate water, depending on the conditions set for the reaction. The solid product VCI3(n) hydrate is obtained directly as a solid by the reaction. Exact conditions for the reaction
are given in Part 2. In the second reaction the vanadium(III) chloride (n) hydrate is dried. The next two steps serve to remove the chlorine. Oxygen is produced by the fifth reaction, which takes place in two stages: = ~VOC13(o~ + ½02
1200K
~VOCla~o) + 1H20 = ]VzOs(o) + 2HC1
400K
] V 2 0 5 ( L ) "~
1C12
1H20 + 1C12
= 2HC1 + 0.502
The process involves two endothermic reactions, to which high temperature heat must be supplied. In the first part of this publication, the process schemes developed are discussed and the principal results of the mass, energy and exergy balance are presented. The second part contains the results obtained from the experimental investigation of the individual reactions. PREFATORY NOTES The balancing and optimization calculations were carried out with the aid of a computer programming system [5], which had already been developed for similar process engineering plants. The aim was to establish a mass-energy and exergy balance for the
Table 1. V/C1 process, reaction scheme Temp.
(K)
Reaction 1 2 3 4 5
2VCl2ts)+ (2n HzO + 2HCI)(L) = 2(VCIs.n H20)(s) + 1H2 2(VCI3.n H20)ts) = 2VCl3ts) + 2n HzO¢G) 4VC13¢s)= 2VC12~s)+ 2VCI4(G) 2VC14~L)= 2VCI3(s/+ 1C12(G) 1C12+ 1H2Otc) = 2HC1 + ½02 Hz + ½02 Range of n: 6 > N > 2.8. * n =2.8. O v e r a l l : H20----~
457
393 433 1039 473 1200
Pressure (bar)
AHMR (MJ/kmol)
85
-45* +378* +236.5 +25.6 +60.1
1
4.5 10 1
458
K. F. KNOCHE and P. SCHUSTER 18HC( (H20) ~ - - ~ I H2
~fu ~ ~,,2j
/Xl=(n)~
[,~1._
!
...... ....
Liquid
~
Gas/liquid
I- .... _ ! ' A
I
Solid
Gas
20HCL 5.6H20
, }
p(n)'~
393K
IL2(VCE3xa.eH20
2.cL
--J'~P~K
_ _ _
2D9HCL 2 n H20 [ ] 2VCk2 +2(HCl.+nHaO) ~ [ ] 2(VCtsx nH20)+8N 2 ~
(H20) I bdr
n 2(VCL~ x oH20) + IH2 2(VCL3 x2.8H20).I.2(n_2B)H20 +8N2
[ ] 2(VCL3x2.OH20)',.2OHCL~ 2VCts+ 5.6H20+20HCL
T(n)
p(n)
(-) (K) (bar) I 6 .%33 4 363 IO 2.8 393 85
Fig. 1. Flowsheet for the H2 production, VCI3.nH20 drying stage of the process. complete process. The balancing resulted from commencing with the material data, chemical engineering flowsheets developed for the V/C1 process and with model simulations of individual plant components which are shown in detail in [4]. First of all, component areas of the overall process were balanced and approximately optimized by varying parameters. The criterion for optimization was minimization of the energy requirement for the particular area. The complete process was then assembled from the optimized parts, from which resulted some minor changes regarding the process flowsheet, caused by the conditions of the overall process. After balancing, an internal heat balance was performed, accounting for vaporizations, condensations and the heat exchange of liquid flows with a minimum temperature difference of 20K, and all other heat flows with a minimum temperature difference of 50K. All numerical values relate to a plant producing 1 kmol/s of hydrogen. MASS A N D E N E R G Y B A L A N C E H2 production and VCI3 drying This section investigates the effect of hydration level n on the energy requirements of this area of the process, where n is the hydration level of the VC13. nH20 produced during the hydrogen production stage. Reaction conditions required to give a variation in hydration level
n are known from the experimental investigation of the hydrogen-producing reaction (see Part 2). The reaction temperature and pressure are given in Fig. 1 as a function of n. The pressure p (n = 2.8) = 85 bar was extrapolated from the available measured values, taking into consideration that in the phase equilibrium calculation for the binary mixture HC1-H20, the highly concentrated hydrochloric acid supplied to the HE reaction was in the liquid phase. This extrapolation only affects the energy balance a minimal amount, due to the low dependence of the fluid enthalpy upon pressure. As can be seen from Fig. 1, dehydration of the VC13 • nH20 occurs in two stages. At the first stage, up to VCla. 2.8H20 is dried at 393K. For rapid removal of the separated crystallization water, nitrogen flows through the drier. Total dehydration of the VCI3 takes place at the second stage at a final drying temperature of 434K. In order to avoid hydrolysis of the VCla with the separated water, drying takes place in a 20 kmol/s stream of HC1 gas. The drying conditions upon which the balancing was based correlate with the experimental investigation. The hydrolysis which could possibly have occurred was neglected in calculations (see Part 2). The gaseous products from the two drying stages are partially condensed whereupon the gaseous flows are fed back to their respective drying stages, and the liquid flows to the HE reaction. The balancing results are summarized in Table 2.
Table 2. Results of the energy balance Hydration level n 6 4 2.8
Q (MW)
H2-reaction Temperature range (K)
-123.8 - 69.1 - 45.2
333-333 363-363 393-393
.VCl3-dehydration Q Temperature (MW) range (K)
(MW)
(MW)
(MW)
801.1 542.7 377.6
911.2 668.8 519.0
-905.2 -666.5 -520.0
0.0 0.1 0.5
* Q--heat; Q z,--heat requirement; Q ab--rejected heat.
333-434 363-434 393-434
~_~zu*
O ab *
Pel
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: ! The heat of hydration of the VC13 • nH20, which must be supplied for dehydration, is also taken into account in the heat requirement of the drying process (see Part 2). It can be seen from Table 2 that as hydration level n decreases, the heat required for drying reduces drastically. The heat required for drying 2.8 hydrate is only 47% of that needed for 6 hydrate. Furthermore it can be seen that the hydrogen producing reaction is an exothermic process, during which less heat is given off with decreasing hydration level. But since the temperature level of this heat energy rises with decreasing n, if a 2.8 hydrate is produced, the heat can be re-introduced into the process. It follows from these realizations that a V/C1 process should be operated with as low a VC13 • nH20 hydration level as possible. PROCESS A R E A : T H E R M A L DECOMPOSITION OF HC1 In this area of the process, the thermal decomposition of HC1 into hydrogen and chlorine takes place. Flowsheet
The process flowsheet is shown in Fig. 2. The previously described hydrogen production (Reactor 1) and the VCI3.2.8H20 drying process (Reactor 2) are shown
in the lower region of the figure. In addition, a further division of the gaseous products from the drying process is considered here. Part of the flow is separated directly by partial condensation, while the other portion is compressed in several stages before being condensed also. With this arrangement the condensation temperature of the pressurized gas is raised, which means that part of the heat given off by condensation can be used for the process. This possibility is only being considered for optimization of the total process. The dried VC13 is preheated to 800K, mixed with WE13 coming from the dechlorination process, and passed to Reactor 3. Here it disproportionates to gaseous VC14 and solid VCI2 in the temperature region 800K-1039K. The VC12 is cooled down to 393K and subsequently passed to the hydrogen reactor. Here it reacts with hydrochloric acid to form H2 and VC13.2.8H20. The gaseous VC14 is liquified, mixed with recycled VC14 from the dechlorination process and passed to Reactor 4. The thermal dechlorination of VC14takes place at 10 bar and at a reaction temperature of 473K. Reaction conditions were determined during the experimental investigation of this reaction (see Part 2). The solid formed, VCI3 is fed to the VCI3disproportionation process, while the mixture of gaseous products (VC1,/C12, 506K, 10 bar) is separated by multi-stage condensation. Pure chlorine (1 kmol/s, 356K, 1 bar) leaves the system by flowpath 79 and flows to the oxygen-producing process. I CL 2 ~ . I0 b r - ~ . - ~ 356K ( 7 9 )
F--IEI-E-~
i-
3.77VCL41
1"~1-=25 M W
LlOb--t~t--43b
--~--7
[ ~ 1 4,02H
I
~
L,2.2oL ~
I
~
1
!800K ;=
L._L__
zlvctz
.~'~LHz
~ ~
" ~ ' ~ L ' ~
~ ...... I
~
I
T43aFY~-
&6HCt
i 14,4HCl$ ( ~ I {H~O) I " ~ 2HCL
I ~".'=(e/'.J
-J 0.1VCL2
-I -/I .
, 12VCL4
,j
!
J~,=.963. I 1 1 S ~
I
I ,,J : /
..... i2L0b°r,
L_ ~ g - f f c C -~ r - - - - - " ~ ) - - -- -- "--'-"'[] [] []
Reactions : 2 V C L 2 + ( 2 H C L * 5 - 6 " 2 0 ) ~ 2(VCt3x2"SH20) + H2 2(VCt3x2.8H20)+2OHCL~ 2VCI,3~'5.6H20~'20HC{. 4VCL 3 ~ 2VCL2~-2VCL 4
--.-SoLid - GOS ------ Liquid
[]
2VCL 4
....
~
459
2VCL3, ICI.2
Fig. 2. Flowsheet for thermal HCI decomposition.
Gas/Liquid
460
K. F. KNOCHE and P. SCHUSTER
Results of the balance
PROCESS A R E A : TWO-STAGE P R O D U C T I O N OF O X Y G E N The energy required by this area of the process is influenced by the flowrate of HC1 required for VCI3 As an oxygen-producing step, the reversed Deacon drying. This influence was investigated in the calcula- reaction tions. This was necessary since the HC1 gas flowrate 1C12 + 1HzO = 2HC1 + ½Oz could not be calculated using the available measurements and literature. To do this requires knowledge of is common to nearly all proposals for thermochemical the equilibrium partial pressure of H20 vapor over water splitting cycles which used chlorine as a base. vanadium(III) chloride (n) hydrate in relation to temThis reaction was investigated in detail experiperature and n. No splitting of drying-process gaseous mentally [6]. The balancing results for this step of the products was involved. Results ot the balance are shown process (including separation of the gaseous products) in Fig. 3. are given by Eisermann [7]. The main difficulties arise The HCI flow was varied between 2 and 20 kmo~/s. in the separation of the gaseous products, whereby a It can be seen that as the HC1 flowrate rises, increases mixture of HC1, H20, C12 and 02 has to be separated. occur, both in the total heat fluxes required/rejected To achieve this requires complicated and energy conafter internal heat exchange. There are two reasons for suming processes such as absorption and rectification. this: firstly, the greater the HC1 flowrate, the more heat For the process proposed here, oxygen is produced has to be supplied to heat it up to the drying temperature in two stages according to the following scheme: of 434K; secondly, as the HC1 flowrate increases, then ~V20~(L) + 1C12 = ~VOC13(G) + ½02 so does the HC1 concentration of the gaseous products, causing a fall in the condensation temperature of the AHmR(1200K) = 37.1 MJ/kmol) HCI-H20 mixture, and consequently a devaluation of the condensation heat. For further balancing of the total ]WOCl3(o) + 1H20(G) ~V205(S) "+"2HC1 process, a HC1 flowrate of 20kmol/s was taken. (AHmR(400K) = - 6 . 9 MJ/kmol) Should a higher flowrate be necessary, extrapolation of Fig. 3 will show that the resulting heat requirement rises The advantage this proposal has over the reversed Deaonly a negligible amount in response. con step lies above all in the considerably simplified separation of product gases. =
Flowsheet
I I00
.___•--•
Heat requirement
900
"~""'~R
el ect ed hea*
70C 3~ \ ResuLting heat requirement sac
-300 o
\ AvaiLabLe
heat
PeL= O,SMW I 4
I 8
I 12
I 16
I 20
bHct(kmot/s ) Fig. 3. Effect of drying agent flowrate on heat fluxes.
Figure 4 shows the process flowsheet which serves as the basis for balancing this area of the process. The flow of chlorine entering the system by path 56 is mixed in with the recycled gas (mainly chlorine, the remainder being VOC13), preheated to a temperature of 1200K and then fed to Reactor 1. Here, the gas reacts with liquid vanadium pentoxide, which has been heated to 1200K. The flow of gaseous reaction products contains C12, VOC13 and 02. The separation of this gas mixture is achieved by multi-stage compression and condensation. During the first two condensation stages, mainly VOC13 is condensed out. The next three stages condense the chlorine at pressures of up to 60 bar. To obtain pure oxygen, the gas is cooled down to 250K during the final condensation stages, and expanded from 60 bar down to 8 bar in a turbine. The turbine outlet temperature is 189K. The gas phase now contains only minute quantities of chlorine, which are extracted by washing the gas in carbon tetrachloride. Pure oxygen leaves the system via outlet 41. The condensed chlorine is recirculated. The vanadium oxide(III) chloride which was produced is now vaporized at 400K and passed to Reactor 2. In this reactor it reacts with water steam to form vanadium pentoxide and HCI gas. Separation of the product gas is done by partial condensation. The gaseous component, consisting of 99% HC1 gas (remainder H20) is passed to the VCI3 drying process while the liquid is vaporized and recirculated.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
461
React ions:
2HCt r-] [] V205+3CL2 " 2VOCl3+1.5 02 ooo2He J ,'~ o~o.~o [ ] 2VOCL~+3H20-----V205+6HCL 295K 2.11 H~. % [-~~voc,30vereLt:3H20+3CL2 -6HC1,+1.502 -
O.2H20 I ~ 0.1 I l i C k
400K
~
IH20
Id--_.
/O
,~T~8~
-
~
I
1,4---
[~
',
) -gMW
I
I~,---
I
-2.w
Ix--l--_. J
:
lx--~.... I 25OK
SOL d Ib
ICL2 T 356K t Ib
2.03 10.5/0.01/ CLz/O2/VOCL3/
(kmot/s)
....
- -
Gas Liquid Gas/liquid
Fig. 4. Flowsheet for two-stage oxygen production.
Results o f the balance
The following is a presentation of balancing results for the most favorable flowsheet arrangement. Figure 5 shows the Q , T diagram. The resulting heat requirement is covered by the H T R process heat between 820K and 1300K. A t temperatures below 950K the temper400 --
Heal
Table 3. Comparison of two-stage oxygen production with the reversed Deacon step Heat flows (MW) Total heat requirement Total rejected heat After internal heat exchange: Heat requirement (HR) Available heat Electric power (EP) Total energy requirement (TER)*
requirernent-~in/h:aetrna t
~
300
xchange
O2-generator Two-step cycle Reversed Deacon 366 -297
588 -510
135 - 67 31.6
375 -298 -4
225
364
* TER = HR + 1/rTel"EP (with r/e=-~ 35%). '(-Rejected heo~c
ature difference for the transfer of heat from high temperature heat to the heat-demand curve becomes very large ( A T ~ 300K-500K). For the total process the matching becomes more favorable. Table 3 shows the most important balancing results---results for two-stage oxygen production are set against those obtained by Eisermann for the reversed Deacon reaction. It arises from this comparison that two-stage oxygen production requires considerably less energy. Moreover exergy losses from the two-stage process are lower, since the heat fluxes exchanged are considerably lower.
200 ,~./f/ I/// I00
Resulting heal requirem~n~c' "~
I ,,AvaiLabLe heat
/
J 300
500
700
900
I I00
I ~k~O
1400
T (K) Fig. 5. Heat flux/temperature diagram for two-stage production of oxygen.
THE T O T A L PROCESS Process flowsheet
The flowsheet of the complete process is put together
462
K. F. KNOCHE and P. SCHUSTER
from the 'thermal HC1 decomposition' (see Fig. 2) and the 'two-stage 02 production' (see Fig. 4) areas of the process. The same applies for the computational flow sheets (see Appendix). There is a steam power plant integrated into the total process (see Fig. 2) which is required to: (a) provide the required electrical power for the total process, and (b) improve the heat balance of the total process by supplying heat from the condensor to the VC13 drying process. To enable this, the steam power plant uses a backpressure turbine (turbine outlet pressure 8bar). The heat of condensation is then given off at a temperature of 443K. The state of live steam is fixed at 230 bar, 818K.
I$Ot"
I00(
50C
Balancing results It can be seen from the heat flux/temperature diagram for O2 production (see Fig. 5) that a heat supply of around 60 MW (vaporization heat for the VOC13, C12 mixture) is needed in the temperature range 350K400K. This cannot be balanced out internally by the total process. Since the condensation heat of the steam power plant is needed, a surplus of electrical power is generated by it. It was attempted to reduce the heat r(K) demands of the thermochemical process by utilizing this surplus electrical power. The process previously shown Fig. 6. Heat flux/temperature diagram for the total process. and described in Fig. 2 lent itself to this purpose, that is, the division and compression of gaseous products from the VC13 drying process. A rise in the condensation temperature of the HCI/H20 mixture is achieved, thereby enabling partial utilization of the condensation heat flux within the process. Table 4. Summary of the most important balancing results for The following presents the balancing results for the the total process overall process, for the case where 20% of the VC13 drying gaseous products are compressed to 5.5 bar. Heat (MW) Detailed results of the mass and energy balance for the total process are given in the Appendix. The heat Total heat requirement 1457.1 flux/temperature diagram for the total process is shown Total rejected heat 1239.9 in Fig. 6. Table 4 contains a summary of important Heat steam power plant 316.0 results from the balancing. It can be seen from the heat Heat thermochemical process + 390.0 flux/temperature diagram that after internal heat exchange, process heat must be supplied to the steam After internal heat exchange: 706.0 boiler and the high temperature reactions (WE13 disheat requirement proportionation and chlorination of vanadium pentoxRejected heat 412.8 ide). Ideally, the resulting heat requirement of the total Internal heat exchange 827.1 process (706 MW) is covered by HTR heat, the helium Required electric power: steam power plant 3.8 temperature of which changes from 1300K at inlet to Thermochemical process + 69.1 660K at outlet. Balancing the electrical power (see Table 4) leaves 72.9 a surplus of around 7.2 MW which is available to drive ancillary machinery and cover friction losses. These Produced eleetric power - 80.1 have not been considered up to now. If the HTR heat Thermal efficiency (%) 40.5 obtained is compared with the calorific value of the H2 Thermal efficiency* (%) 42.5 produced, a plant efficiency of 40.5 or 42.5% (see Table 4) is obtained. Exergy losses from the complete plant * Internal heat balance with a minimum temperature difare 245 MW, distributed over the individual process ference of 12K for vaporizations, condensations and the heat areas as shown in Fig. 7. exchange of liquid flows.
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
~'vJ
y----~ x too (%)
0
I0
Hz-generation and drying
F
Steam power-pLarR
~ 1 8 . 1
Reactions of O2-generation
~
20
Dechtor ination
40
50
,o,
computational reasons. Tables A1 and A3 contain the results of the mass balance, while the energy balance is shown in Tables A2 and A4. The abbreviations written into the blocks of the computer flowsheets (Figs A1 and A2) and in the Tables A2 and A4 have the following meanings:
Reactors
6.5
VCL~-disproportionat ion ~"~ 6 I Compressors and pumps
30
463
Tu =300K
] 3.9 1.1
GLEI GENE GQPF
Remaining heat exchange ~ 9 . 2
Fig. 7. Relative exergy losses from individual plant components and process areas. The greatest irreversibilities occur in the H2 production and VCI3 drying (including gaseous product separation) areas of the process, which account for 55 % of the total exergy loss. In addition, exergy losses from the steam p o w e r plant (18.1%) and from the VC13 disproportionation and O2-producing reactions (each around 6%) are also significant.
No performs the mass balance at a given reaction temperature and pressure No performs the mass balance at adiabatic reaction temperature (iterative process) No performs the mass balance at given temperature steps (adiabatic reaction temperature up to the given reactor outlet temperature = heat profile of the reator) No signifies a special reactor 09 VOC13 hydrolysis reaction 10 V205 chlorination 12 VC13 disproportionation 13 H2 producing reaction 14 VC14 dechlorination Drying VC13 dehydration
Separators REFERENCES 1. J. E. Funk and R. N. Reinstrom, System study of hydrogen generation by thermal energy, Allison Division of General Motors, EDR 3714, Vol. 11, supplement A (1964). 2. G. De Beni, Euratom Staff, Hydrogen production from water using nuclear heat, Progress Report No. 3, EUR 5059e (1974). 3. F. Behr, Personal communication, Lehrstuhl fiir Reaktortechnik, RWTH Aachen, published in 4. 4. P. Schuster, Experimentelle unteruschung und Bilanzierung von Vanadium/Chlor- und Vanadium/Brom-Mehrstufenprozessen zur thermochemischen Erzeugung von Wasserstoff, Ph.D. thesis, Aachen (1980). 5. K. T. Knoche, H. Cremer and W. Eisermann, Balance and optimisation procedure for thermochemical cycles for hydrogen production, First World Hydrogen Conference, Miami (1975). 6. H. Cremer, D. Breywisch, S. Hegels, W. Schneider, P. Schuster, G. Steinborn, G. Wozny and G. Wiister, Entwicklung von Mehrstufenprozessen zur Wasserstofferzeugung mit Hilfe von Kernw~irme, Final Report Project, ET 4031A, German Ministry for Research and Technology (1978). 7. W. Eisermann, Bilanzierung von Eisen-Chlorprozessen zur Thermischen Wasserzersetzung, Ph.D. thesis, Aachen (1977). APPENDIX This appendix contains the full set of results for the mass and energy balance, together with the necessary explanatory notes on the computational flowsheets. To carry out the balancing by computer, the process flowsheets (see Figs 2 and 4) were translated into computer code (see Figs A1 and A2). This coding is used on the computational flowsheets, which in some places are more detailed than the process flowsheets, for
SEPARA separation of a multi-phase input flow into gas and liquid/solid phases according to the phase equilibrium TRENNE high purification
General apparatus MIXCHE mixing of up to five input flows; evaluation of the adiabatic mixture temperature HEATER exchange of heat until a given outlet temperature is reached and the determination of a heat profile in relation to temperature PUMPVD/ pump, compressor/turbine; changTURBIN ing the pressure to a given outlet pressure; evaluation of electrical power for a given isentropic efficiency (compressor = 0.9; turbine = 0.85); evaluation of the adabatic outlet temperature DROSSE adiabatic throttling SPLIT No division of an inlet flow into two separate flows HOLDUP definition of the mass flow of a particular component in a mixture
Apparatus for regulation and control MESSEN) . . . . REGEL No] serve to transmit mtormatxon to RETEMpJOther parts of the plant
HCLH20
VCl 2
'I O2-generation
I ~from
HCI
VCL2
VCL3xnH20 VCL2
, HCL(H ) ) ~
(~
I I
)
H 2
_
HCL.H20
_
PUMP VD
HCL, H20
"fCl. H20
I
I
I I
i
Fig. A1. Computer flowsheet for the thermal HCI decomposition.
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VCI
VCI4 CL2
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VCL4 Ct2
CL2 VCL4
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K . F . KNOCHE and P. SCHUSTER Table A1. Composition/mass flows of streams for the thermal/HC! decomposition (compare with Figs A1 and 2)
Stream No.
Unit From To
H2
H20
HCI 16.07547 1.67591 1.67591 2.09489
1 2 3 4
15 1 2 5
1 2 3 6
4.48623 4.47183 4.47183 5.58979
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
0 6 0 7 7 18 17 8 9 9 9 10 11 29 11 13 14 14 12 13 20 0 19 0 16 1 49 0 48 35 32 30 35 40 41 42 43 44 45 0 50 51 52 51 52 52 53 54 55 56 55 58 58 57 61 60
6 7 7 0 8 11 18 9 7 10 0 11 29 30 12 14 15 15 13 20 21 19 17 18 17 16 9 49 49 47 35 31 40 41 42 43 44 45 50 51 51 0 51 52 54 53 30 55 56 58 64 64 62 59 57 61
5.58979 5.58979
5.58979 0.01800 0.01800 5.58979
kmol/s CIE VCh
VCI2
VCl3
HH20
2.09489 1.99994 1.99995 2.09489 19.99945 19.99939 2.09489
1.00000 0.09489
0.09935
2.00000
5.58979
0.09489
0.09935 0.09935 0.09935
2.00000 2.00000 2.00000
5.58979
1.00000
5.50779 4.48623
20.09434 16.07547
4.48623 5.60779 1.12156 1.12156
16.07547 20.09434 4.01887 4.01887 1.99994 1.99994 19.99945 14.39956 14.39956
0.01440 0.01440
2.09936 2.09936 2.09935
0.09935
4.00000
2.00000 3.77359 2.00000 0.00000 0.32070 3.77359 1.32070 1.77359 0.32070
2.00000 2.00000 1.32070 1.00919 1.00919 0.31151 0.00300 1.00619 1.00000 1.00000 1.00000
1.77359 0.04593 0.04593 1.72765 0.01346 0.03247
T (K)
P (bar)
280 280 281 393
1.00 1.00 1.00 85.00
393 393 393 393 393 434 434 393 393 393 393 393 434 510 434 363 280 363 363 363 479 293 434 434 434 280 393 393 393 961 800 510 961 430 463 455 450 450 473 473 470 473 473 470 506 506 510 400 400 390 400 390 390 356 355 370
85.00 85.00 85.00 85.00 85.00 1.00 1.00 85.00 85.00 85.00 85.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.30 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.00 2.00 2.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 10.00 1.00 10.00 10.00 10.00 10.00 10.00 10.00 1.00 1.00 10.00
(connnued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1
467
Table Al.---continued. Stream No. 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94
Unit From To 60 62 64 65 8 8 47 46 31 32 33 34 34 36 37 38 39 63 59 63 21 22 23 24 24 25 26 26 4 27 28 3 8 8
H2
64 63 65 50 14 1 48 47 32 33 34 46 36 37 38 39 50 60 0 64 22 23 24 25 25 26 27 3 5 28 17 4 24 26
H20
kmol/s C12 VCI4
HC1
VCl2
WE13
HH20
0.01511 1.00619 0.03247 0.32070 1.77359 0.32070 1.77359 5.58979 5.58979
2.09489 2.09489 2.09935 2.09935 0.09935 0.09935 0.09935 2.09935
4.00000 4.00000 4.00000
2.00000 2.00000 2.00000 2.00000 2.00000 1.00000 0.01511 1.00000 0.00619 0.01736 1.12156 1.12156 1.12156
4.01887 4.01887 4.01887
1.12156 1.12156 0.00360 1.11796 5.58979 0.00360 0.00360 5.58979 5.58979 5.58979
4.01887 4.01887 3.59989 0.41898 2.09489 3.59989 3.59989 2.09489 2.09489 2.09489
T (K)
P (bar)
370 370 399 473 393 393 961 961 800 800 800 1040 1040 495 473 473 473 370 356 370 379 506 400 322 400 322 322 322 286 314 434 285 393 393
10.00 10.00 10.00 10.00 85.00 85.00 1.00 1.00 1.00 1.00 1.00 4.50 4.50 4.50 4.50 10.00 i0.00 10.00 1.00 10.00 2.30 5.50 5.50 5.50 5.50 5.50 5.50 5.50 85.00 1.00 1.00 1.00 85.00 85.00
Table A2. Composition/mass flows of streams for the two-stage production of oxygen (compare with Figs A2 and 4) Strea:~ No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Unit From To 53 1 2 2 3 4 5 6 7 8 9 10 11 12
1 2 3 0 4 72 57 7 8 9 10 11 12 13
kmol/s 0 2
H20
HCI
C12
VOC13
V205 0.33333 0.33333
0.50000
2.34644
0.70774
0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000 0.50000
2.34644 2.34644 2.34644 2.05003 2.05003 2.02146 2.02146 2.02146 0.52725 0.52725
0.70774 0.70774 0.70774 0.01334 0.01334 0.00219 0.00219 0.00219 0.00000 0.000130
T (K)
P (bar)
400 1200 1200 1200 410 497 293 381 293 293 370 293 293 373
1.00 1.00 1.00 1.00 1.00 2.50 2.50 6.00 6.00 6.00 13.00 13.00 13.00 28.00
(conanued)
468
K . F . KNOCHE and P. SCHUSTER Table A2..---con~nued. Stream No.
Unit From To
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
13 11 15 16 14 21 22 14 17 18 19 20 23 28 23 24 25 26 27 29 29 30 32 33 34 30 31 35 8 36 37 38 37 40 39 39 41 42 42 43 44 0 46 45 47 48 0 47 2 49 50 0 51 51 65 52 53 68 69 55 53
14 56 16 20 21 22 23 17 18 19 20 27 64 29 24 25 26 27 35 30 32 32 33 34 35 31 0 44 36 37 38 63 40 61 42 41 43 43 49 44 45 46 45 47 48 2 47 0 47 71 51 51 0 53 52 53 66 0 55 70 51
kmo~s 02
H20
HCI
0.50000
0.50000 0.50000 0.50000
0.50000 0.50000
0.50000
C12
VOC13
0.52725 1.49421 1.49421 1.49421 0.15670 0.15670 0.15670 0.37054 0.37054 0.37054 0.37054 1.86475 0.06263 0.06263 0.09408 0.09408 0.09408 0.09408 1.95883 0.00365 0.05898 0.00365 0.06263 0.06263 0.06263
0.00000 0.00219 0.00219 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00219 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
2.02146 0.02857 0.02857 0.02057 0.02057 0.00800 0.00800 0.02607 0.19820 0.29892 0.02607
0.00219 0.01115 0.01115 0.01114 0.01114 0.00000 0.00000 0.66683 0.03809 0.03371
V205
0.50000 0.50000
0.32499 2.34644 1.00000 1.00000 3.34644 3.34519 3.34644 14.00000 14.00126
0.66683 0.03871 0.04090
0.04090 0.04090 0.04107 -0.00251
0.20000
0.10713
0.20000 1.00158 1.00158 0.20158 0.00158 0.20001 0.20001
0.10713 2.10713 1.99982 0.10732 0.10732
0.66683 0.79019 2.00000 2.00028 0.78991 0.12324 0.12324 0.12324 0.00060
T (K) 293 293 239 343 293 376 293 293 293 239 343 343 293 189 293 293 239 343 343 189 189 189 189 189 343 189 298 343 293 249 249 343 249 343 343 343 343 343 343 343 343 356 343 343 343 1200 343 343 1200 400 400 400 400 400 283 400 400 293 293 400 400
P (bar) 28.00 13.00 1.00 1.00 28.00 60.00 60.00 28.00 28.00 1.00 1.00 1.00 60.00 8.00 60.00 60.00 1.00 1.00 1.00 8.00 8.00 8.00 60.00 1.00 1.00 8.00 8.00 1.00 6.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
(continued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1 Table A2.---continued. Stream No. 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
Unit From To 56 57 57 58 59 60 61 59 62 63 64 0 0 65 66 67 67 54 54 68 0 70 71 0 72
15 6 58 59 60 61 41 62 63 39 28 65 65 0 67 54 69 68 69 65 70 50 50 71 5
kmol/s 02
H20
HCI
0.50000
0.50000 1.00000 1.02026 1.01868 0.20158 0.00158 0.20001 0.00158
Clz
VOCI3
1.49421 2.05003 0.29641 0.29641 0.09271 0.09271 0.10071 0.20370 0.20370 0.22427 0.06253
0.00219 0.01334 0.69440 0.69440 0.00062 0.00062 0.00062 0.69378 0.69378 0.70492 0.00000
2.10713 1.99982 0.10732 1.99982
V2Os
0.12324 0.01004 0.11321 0.01004
0.00158 0.20000 0.20000
1.99982 0.10732
0.50000
2.34644
0.12324 0.66666 0.66666 0.70774
T (K)
P (bar)
293 293 293 279 279 343 343 279 343 343 250 283 283 283 293 293 293 293 293 293 400 400 400 400 370
13.00 2.50 2.50 1.00 1.00 1.00 1.00 1,00 1.00 1.00 60.00 1.00 1,00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 2.50
Table A3. Energy balances of units for the thermal HCI decomposition (compare with Figs A1 and 2) Unit No.
Unit Name
1
REGEL4
2 3
MIXCHE
4 5 6 7
PUMPE1
PUMPE1 HEATER HOLDUP REGEL3
9
MESSEN GLEI13
10 11
HEATER DRYING
12 13
HEATER SPLIT0
14 15 16 17
RETEMP HEATER HEATER MIXCHE
8
Enthalpy (MW) in out -2869.1 0.0 - 1526.7 -1526.4 -378.1 -1904.5 -1906.0 -1855.8 -1855.8 -183.0 -1855.8 -1855.8 -952.1 -2855.9 -1773.3 -2856.3 -3111.4 -3166.7 0,0 -2533.3 -2533.3 -1341.6 -176.9 -1277.1 -319.3
-1526.7 -1341.6 - 1526.4 -1904.5 0.0 1906.0 1855.8 -1855.8 -183.0 -1855.8 1855.8 -2855.9 2.7 -2856.3 -1140.5 -3111.4 -3166.7 -2533.3 -633,3 -2533,3 -2869.1 -1277.1 -1773.3 0.0 0.0
Entropy (MW/K) in out 3.080 0.000 0.413 0.413 0.108 0.522 0.514 0.749 0.749 0.317 0,749 0.749 0.247 0.500 3.962 0.504 5.219 5.080 0.000 4.064 4.064 2.670 0.396 2.853 0.713
0.413 2.670 0.413 0.522 0.000 0.514 0.749 0.749 0.317 0.749 0.749 0.500 0.102 0.504 0.347 5.219 5.080 4.064 1.016 4.064 3.080 2.853 3.962 0.000 0.000
Q (MW)
Temp range (K-K)
P(EL) (MW)
AD
0.0
AD AD
0.2 0.0
-1.7 50.2 AD AD
286 286
286 393
AD -45.2
393
393
0.0 0.0
AD 377.6
393
434
0.0 0.0
434
363
363 280
280 434
-55.2 AD AD -335.7 64.6 AD
0.2 0.0 0.0 0.0
0.0 0.0 0,0 0.0 0.0 0.0
(continued)
469
470
K. F. KNOCHE and P. SCHUSTER Table A3.--continued.
Unit No.
Unit Name
18 19 20 21 22 23 24 25 26
HOLDUP HEATER PUMPVD HEATER PUMPVD HEATER RETEMP HEATER REGEL4
27 28 29 30
DROSSE HEATER HEATER MIXCHE
31 32
HEATER SPLIT
33 34
HEATER GQPF12
35
GQPF12
36 37 38 39 40 41 42 43 44 45 46 47
HEATER HEATER PUMPVD HEATER HEATER PUMPVD HEATER HEATER PUMPVD HEATER HEATER MIXCHE
48 49 50
HEATER HOLDUP MIXCHE
51
REGEL2
52
GQPF14
53 54 55
HEATER HEATER SEPARA
56 57 58
HEATER HEATER SEPARA
59 60
HEATER TRENNE
61 62 63
DROSSE HEATER SEPARA
Enthalpy (MW) in out -1773.3 -185.1 -633.3 -615.4 -631.1 -611.7 -628.4 -528.4 -709.9 0.0 -331.8 -331.8 -1140.5 -1124.6 -1080.4 -2205.1 -2080.7 0.0 -2080.7 -2080.7 0.0 0.0 0.0 -898.1 -1009.5 -1083.8 -1083.8 0.0 0.0 0.0 0.0 0.0 0.0 -844.0 0.0 -857.8 -857.8 -952.1 0.0 -949.3 -1083.8 -1083.8 -2033.1 -2033.1 0.0 -1081.2 -883.8 -979.9 0.0 -20.5 1.9 -21.5 0.0 1.9 -5.9 0.0 1.9 -14.0 -15.7 0.0
1773.3 175.9 -615.4 -631.1 -611.7 -628.4 -628.4 -709.9 -331.8 -378.1 -331.8 -319.3 -1124.6 -2205.1 0.0 -2080.7 0.0 -2080.7 -2080.7 -844.0 -898.1 0.0 0.0 -1009.5 -1083.8 1083.8 1083.8 0.000 0.0 0.0 0.0 0.0 0.0 -857.8 -857.8 0.0 -952.1 -952.1 -2033.1 0.0 0.0 -1083.8 -2033.1 -883.8 1081.2 -1080.4 -979.9 -20.5 -959.3 -21.5 1.9 -7.5 - 14.0 3.5 1.9 -8.4 1.9 -15.7 -5.9 -9.8
Entropy (MW/K) in out 3.962 0.373 1.016 1.024 0.987 0.995 0.958 0.958 0.739 0.000 0.630 0.679 0.347 0.381 0.367 0.748 0.941 0.000 0.941 0.941 0.000 0.000 0.000 0.895 0.744 0.593 0.593 0.000 0.000 0.000 0.000 0.000 0.000 0.408 0.000 0.394 0.394 0.247 0.000 0.620 0.593 0.593 1.214 1.214 0.000 0.366 0.963 0.756 0.000 0.233 0.229 0.230 0.000 0.229 0.216 0.000 0.210 0.226 0.222 0.000
3.962 0.396 1.024 0.987 0.995 0.958 0.958 0.739 0.630 0.108 0.679 0.713 0.381 0.748 0.000 0.941 0.000 0.941 0.941 0.408 0.895 0.000 0.000 0.744 0.593 0.593 0.593 0.000 0.000 0.000 0.000 0.000 0.000 0.394 0.394 0.000 0.247 0.247 1.214 0.000 0.000 0.593 1.214 0.963 0.366 0.367 0.756 0.233 0.524 0.230 0.229 0.004 0.226 0.233 0.210 0.004 0.229 0.222 0.216 0.006
Q (MW) AD 8.2 AD -15.7 AD -16.7 AD -81.6 AD AD 12.6 15.9 AD 124.4 AD AD 338.6
Temp range (K-K)
P(EL) (MW) 0.0 0.0 17.9 0.0 19.4 0.0 0.0 0.0 0.0
293
434
479
379
506
400
400
322
314 434
434 510
510
800
800
1040
0.0 0.0 0.0 0.0 0.0 0.0
AD
0.0 0.0 0.0
-111.3 -74.3 AD AD AD AD AD AD AD AD -13.8 AD
1040 495
495 473
1040
961
-94.4 AD AD
961
393
AD
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0
68.1
473
506
0.0
AD -96.1 AD
506
400
0.0 0.0 0.0
-1.0 AD AD
400
390
0.0 0.0 0.0
1.6 AD
356
400
0.0 0.0
390
370
AD -1.7 AD
0.0 0.0 0.0
(continued)
THERMOCHEMICAL PRODUCTION OF HYDROGEN BY A VANADIUM/CHLORINE CYCLE: 1 Table A3.--continued. Unit No.
Unit Name
64
MIXCHE
65
HEATER
Enthalpy (MW) in out -959.3 -7.5 -8.4 -9.8 -985.1
-985.1 0.0 0.0 0.0 -949.3
Entropy (MW/K) in out 0.524 0.004 0.004 0.006 0.537
0.537 0.000 0.000 0.000 0.620
Q (MW)
Temp range (K-K)
P(EL) (MW)
AD
35.7
0.0
399
473
0.0
AD = adiabatic. P(EL) = electrical power.
Table A4. Energy balances for the two-stage production of oxygen (compare with Figs A2 and 5) Unit No.
Unit name
1 2
HEATER GQPF10
3 4 5 6 7 8
HEATER PUMPVD HEATER PUMPVD HEATER SEPARA
9 10 11
PUMPVD HEATER SEPARA
12 13 14
PUMPVD HEATER SEPARA
15 16 17 18 19 20
DROSSE HEATER TURBIN DROSSE HEATER MIXCHE
21 22 23
PUMPVD HEATER SEPARA
24 25 26 27
TURBIN DROSSE HEATER MIXCHE
28 29
TURBIN SEPARA
30
TRENNE
31 32
HEATER MIXCHE
33
DROSSE
Enthalpy (MW) in out -514.7 -446.0 85.5 -323.4 -463.6 -476.0 -9.9 -2.4 -11.4 0.0 -2.9 3.4 -30.1 0.0 0.5 2.0 -7.2 0.0 -29.6 -29.6 -7.0 -7.0 -7.0 0.7 0.5 -0.2 1.5 -1.9 0.0 -1.8 -1.8 -1.8 1.3 0.1 -1.8 -3.1 0.0 -1.5 0.0 -1.5 -1.5 -0.1 - 1.6
-445.0 -323.4 0.0 -463.6 -448.7 -516.1 -2.4 -11.4 -2.9 -8.6 3.4 -30.1 -0.5 -29.6 2.0 -7.2 -0.2 -7.0 -29.6 0.7 -7.0 -7.0 0.5 1.3 0.0 1.5 -1.9 -0.1 -1.8 -1.8 -1.8 0.1 1.4 0.0 -3.1 -1.5 -1.5 -0.1 -1.5 -0.0 -1.6 0.0 - 1.6
Entropy (MW/K) in out 0.058 0.144 0.936 1.121 0.931 0.871 0.554 0.558 0.530 0.000 0.524 0.527 0.410 0.000 0.203 0.204 0.171 0.000 0.203 0.218 0.049 0.049 0.054 0.341 0.084 0.122 0.123 0.111 0.000 0.012 0.012 0.014 0.426 0.021 0.091 0.093 0.000 0.089 0.000 0.088 0.004 0.000 0.004
0.144 1.121 0.000 0.931 0.937 0.750 0.553 0.530 0.524 0.007 0.527 0.410 0.203 0.203 0.204 0.171 0.122 0.049 0.218 0.341 0.049 0.054 0.084 0.426 0.000 0.123 0.111 0.099 0.012 0.012 0.014 0.021 0.447 0.000 0.093 0.089 0.004 0.000 0.088 0.094 0.004 0.000 0.006
Q (MW)
Temp range (K-K)
P(EL) (MW)
68.8 37.1
400 1070
1200 1200
0.0 0.0
-140.3 AD -40.1 AD -9.0 AD
1200
410
370
293
381
293
0.0 15.0 0.0 7.5 0.0 0.0
AD -33.5 AD
370
293
6.2 0.0 0.0
AD -9.2 AD
373
293
2.5 0.0 0.0
239
343
239
343
376
293
AD 30.3 AD AD 7.5 AD AD -3.4 AD AD AD 1.9 AD
239
343
0.0 0.0 0.0 0.0 0.0 0.0 1.7 0.0 0.0 -0.0 0.0 0.0 0.0
AD AD
-1.3 0.0
AD
0.0
1.5 AD AD
189
298
0.0 0.0
0.0 (continued)
471
472
K. F. KNOCHE and P. SCHUSTER Table A4.---continued. Unit No.
Unit name
34 35
HEATER MIXCHE
36 37
DROSSE SEPARA
38 39
HEATER SEPARA
40 41
HEATER MIXCHE
42
TRENNE
43
MIXCHE
44
MIXCHE
45
MIXCHE
46 47
HEATER REGEL1
48 49 50
HEATER HEATER MIXCHE
51
REGEL3
52 53
HEATER GENE09
54
TRENNE
55 56 57
HEATER TURBIN SEPARA
58 59
DROSSE SEPARA
60 61
HEATER MIXCHE
62 63
HEATER MIXCHE
64 65
HEATER REGEL4
66 67
HEATER SEPARA
68 69
MESSEN MIXCHE
70 71 72
HOLDUP HOLDUP HEATER
Enthalpy (MW) in out -1.6 1.4 0.1 -8.6 -8.6 0.0 -8.6 -501.6 0.0 -0.0 -25.5 -0.3 -476.1 0.0 -25.8 0.0 1.5 -25.7 -24.2 1.5 1.5 -22.8 20.5 -22.8 -475.7 -140.2 -447.5 -587.8 -1342.6 -238.1 -587.6 -239.6 - 192.3 0.0 -160.3 -29.6 -516.1 0.0 -506.2 -506.1 0.0 -0.5 0.0 -0.3 -505.7 -7.8 -493.8 -0.1 -287.7 -293.5 -319.4 -345.3 0.0 -185.5 - 153.0 -7.2 -140.2 -447.5 -448.7
AD = adiabatic. P(EL) = electrical power.
0.1 1.5 0.0 -8.6 -8.6 -0.0 -7.8 -475.1 -25.5 0.0 -25.8 0.0 0.0 -475.7 -25.7 0.0 -24.2 0.0 -22.8 0.0 1.5 -22.3 20.6 85.5 -447.6 -587.7 0.0 -1342.8 -587.7 -239.6 -514.7 -319.4 - 185 -7.2 - 140.2 -29.6 -9.9 -506.2 -505.1 -0.5 -505.7 -0.3 -0.3 0.0 -493.8 -501.6 0.0 -1.8 -288.1 -293.0 -345.3 -192.3 -153.0 -185.5 - 160.3 0.0 -140.2 -447.5 -475.0
Entropy (MW/K) in out 0.006 0.447 0.014 0.007 0.007 0.000 0.005 0.224 0.000 0.002 0.059 0.023 0.165 0.000 0.082 0.006 0.462 0.088 0.550 0.228 0.228 0.778 3.190 0.778 0.161 0.107 0.232 0.343 0.690 0.066 0.343 0.199 0.377 0.000 0.047 0.208 0.750 0.000 0.196 0.197 0.000 0.021 0.002 0.021 0.177 0.008 0.216 0.099 0.066 0.067 0.505 0.422 0.000 0.373 0.045 0.002 0.107 0.232 0.937
0.014 0.462 0.000 0.007 0.005 0.002 0.008 0.165 0.059 0.002 0.082 0.000 0.006 0.161 0.088 0.000 0.550 0.000 0.778 0.000 0.228 0.778 3.190 0.936 0.232 0.343 0.000 0.696 0.343 0.199 0.058 0.505 0.373 0.002 0.107 0.208 0.554 0.196 0.197 0.021 0.177 0.021 0.023 0.000 0.216 0.224 0.000 0.091 0.066 0.067 0.422 0.377 0.045 0.373 0.047 0.000 0.107 0.232 0.871
Q (MW) 1.7 AD
Temp range (K-K) 189
343
P(EL) (MW) 0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
AD
0.0
AD
0.0
AD
0.0
AD
0.0
AD AD
0.0 0.0
108.3 28.1 AD
343 343
1200 400
AD 48.5 -6.9
0.0 283 400
400 400
AD 20.1 AD AD
0.0 0.0 0.0
0.0 0.0 0.0
293
400
0.0 0.0 0.0
AD AD
0.0 0.0
AD AD
0.0 0.0
11.9 AD
279
343
0.0 0.0
-1.7 AD
293
250
0.0 0.0
-26.0 AD
400
293
0.0 0.0
AD AD
0.0 0.0
AD AD -27.4
0.0 0.0 0.0
497
370