00306 Progress in the planar CPn SOFC system design

03

Gaseous fuels(sources,properties,

97100299

Method for deslagging

recovery, treatment) a partial oxidation

reactor

Brooker. D. D. and Falsetti, J. S., PCT Int. Appl. WO 96 17,904 (Cl. CIOJ3/OX), 13 Jun 1996, US Appl. 365.219. 8 Dee 1994. This paper provideq a method for facilitating the deslagging of a partial oxidation reactor used to produce syngas. The slag comprises vanadium trioxide and a siliceous material that accumulates on the interior walls of of the syngas production the partial oxidation reactor as a byproduct proces\. Deslagging is achieved by controlled oxidation, here the vanadium to glass weight ratio is maintained equal or greater than 3:2. operating the reactor at a temperature of at least 2000”F, and maintaining controlled oxidation conditions sufficient to convert the vanadium trioxide in the slag to vanadium pentoxide.

Method for 97/00300 removal of heavy metals

gasification

of petroleum

coke

with

Tsujino. T. et crl., Jpn. Kokai Tokkyo Koho Jl) 0X.143,X76 [06,143,X76] (Cl. ClOJ3146). 4 Jun IYYh, Appl. Y4i 2X8.1.57. 22 Nov. lYY4. (In Japanese) This paper looks at the method for gasification of petroleum coke with removal of heavy metals which includes partial oxidation of petroleum coke and inorganic minerals (for example coal ashes, slag) in a gasifier for gasification. withdrawing heavy metal\ having high melting point from the unreacted materials discharged from the gasifier then recycling the remainder unreacted materials back to the gasifier for re-gasification together with coke and inorganic minerals.

97/00301 membrane

Modelling reactor

endothermic

reactions

in a compound

1096. . Purif.. 10, (I), 47Assahumrungrat, S. and White, D. A., 52. This paper models the performance of a membram reactor. The membrane, a composite alumina-based one, is packed with a catalyst and allows low molecular weight gases to diffuse through it at a faster rate than gases with a higher molecular weight. This allows a greater conversion to be achieved in one pass through the reactor. The reaction that is specifically considered in this paper is the dehydrogenation of methyl-cyclohexane to toluene with the production of hydrogen. This latter species is preferentially removed by the membrane. Data for the performance of the membrane have been estimated from previous experiments using single gases and the mechanisms considered are Knudsen and bulk flow. Surface flow is not considered in the model as it is possibly not important as the endothermic reaction is carried out at a high temperature. A standard kinetic model is also incorporated in the calculations. The corrleations of maximum effective length of membrane reactors and maximum percentage conversion as functions of the feed velocity and the membrane diameter are demonstrated in this paper. This paper also considers the hehaviour of a compound reactor in which the first section is a straightforward ‘plug flow’ reactor where the catalyst is confined in an impermeable tube with the same internal diameter as the membrane. This ia followed by a section containing the memhrane. The reason for considering this configuration is to avoid unnecessary leakage of methyl-cyclohexane feed in the initial stages of the reaction. This innovation leads to predicted increases in the overall conversion of the process.

New correlation 97100302 buffer solution in a Raschig

for liquid hold-up of sodium citrate ring packed coluqn und Sqmration.1996, 10, (4), 199-205.

Brigyi. I. et al., c;cr.s Purificurion Dynamic liquid hold-up was measured with an air/aqueous sodium citrate buffer solution at 20-40 C, and an air/water system at 23’ C. in a 0.1 m diameter/l m high glass column covered by a heat-isolating vacuum jacket and packed with 0.012 m nominal size ceramic Raschig rings. The superficial gas velocity range was extended to 1.2 m s-‘. Experimental results of this work were compared with literature data, with different correlations and with a general equation. All expressions were found to be unacceptable for the air/buffer system and useable for the air/water system, In the case of the air/buffer solution a new correlation is recommended on the basis of our measured data and literature values.

97100303 Oxidative coupling of methane to Cc2 hydrocarbons in ascending-flow column reactor with additional cracking and methanation steps Inomata, M. et ol., Eur. Pat. Appl. EP 716,064 (Cl. CO7C2/84), 12 Jun 1996, JP Appl. Y4/301,216. 5 Dee 1994. In this paper the oxidative coupling of methane is carried out in the presence of an oxygen-containing gas and a catalyst, in which: the feed gases are introduced at the bottom of a column; the coupling reaction proceeds in an ascending stream; the product containing a Cmz hydrocarbon is withdrawn at the tap of the column: the catalyst is separated from the product gases in a cyclone. collecting catalyst at the hottom of a second column, and the catalyst from the second column is returned to the first (coupling reaction) column. The coupling step is carried out at 75%900°C and an atmospheric pressure to IO kg/cm’ (gauge), optionally in a column operated as a fluidized bed. This method can also incorporate such steps as the separation of the CLz fraction from non-condensible product gases, cracking of the saturated C 1 components to ethylene, and methanation of the carbon oxides in the non-condensible product gas fraction to manufucturing additional methane which is returned to the coupling reactor.

22

Fuel and Energy Abstracts

January 1997

Prevention of ash component 97100304 gasifier in gasification of petroleum coke

deposit

on wall

of

Tsujino, T. ef al., Jpn. Kokai Tokkyo Koho JP OX,I43.X75 [Yf~,l43,87S] (Cl. ClOJ3146). 4 Jun 1996. Appl. Y4/28X,lSl. 22 Nov. IYYJ. (In Japancsc) The prevention is carried out by mixing 3 weight parts (to I weight part a\h in petroleum coke) inorganic minerals (for exmaple coal ashes, slag) Into coke followed hy gasification operation at a temperature higher flow point of the inorganic minerals.

97/00305 Process effects on activated carbon performance and analytical methods used for low level mercury removal in natural gas applications McNamara. J. D. and Wagner, N. J.. I YYh, (;LI.s ,S<‘/‘. &,rif.. I(I. (2). 137140. Type HGR-’ activated carbon is frequently employed to protect aluminum heat exchanger? in liquefying natural gas. Residual mercury levels in the treated gas are frequently at or near the limits of detection. challenging, the analytical methods employed. Additionally, process variables and variations in the testing environment can affect the analytical procedures used to measure low levels of mercury. The impact of process variable5 on adsorbent performance will also be described.

97100306

Progress

in the planar CPn SOFC system design

Frost. L. J. r/ nl.. ./our-rlnl o/‘Po&jer Sotrnes. JulyyAug IYYh. 6 I. ( l-2). 13% 1.3’). A high cfflciency. modular planar solid oxide tucl cell module using the patented CPn module ha\ been demonstrated on pipclinc natural gas. The results of this I.4 kW thermally integrated module. along with stack/cell teats. havr verified the multi-stage oxidation concept. Design and analysis of a IO kW mobile electric power generating system using this technology predicts a final module with > 40? system efficiency when operated on logistics fuel. However. thi\ analysis also stresses the need for improved cell performance at lower temperature. Ceria-based planar single cells have been demonstrated at > 300 mW/cm’ at 75O’C.

97100307 coal beds

Prospects

for industrial

recovery

of methane

from

Zimakov. B. M.. et N/., f&o/~. Tr. Pron!-sri., 1996. (2). 2X-32. (In Russian) This paper explores the prospects of methane recovery from coal {earns in Russia. The progress of the industry in the United States is also rcvicwcd.

97100308 umns

Rapid

assessment

of thermally

coupled

side col-

Finn, A. J., (;a.~ Purijk~rima& S~pur~tio~r, lYY6. IO, (3). If>%1 75. Thermally coupled distillation is well proven in low temperature gas processing where energy is relatively expensive. Although the thermodynamic efficiency of thermally coupled columns is similar to conventional columns, thermal coupling reduces energy flows. This can lead to attractive savings in both energy and capital cost. This paper shows that the conventional Fenske-Underwood-Gilliland method for short-cut distillation design is as appropriate for thermally coupled columns as it is for conventional distillation. This enables comparisons of conventional and thermally coupled columns to be made easily, and should help to make thermal coupling a more accepted means of improving energy efficiency in distillation systems.

97100309 Removal of VOCs using activated carbon cloth

from

humidified

gas

streams

Cal, M. P. et ul., 1996, G‘u.5 Sep. f%rrif., IO. (2). Il7-121. This research investigates the effects of relative humidity (RH) on the adsorption of soluble (acetone) and insoluble (benzene) volatile organic compounds (VOCs) with activated carbon cloths (ACC). A gravimetric balance was used in conjunction with a gas chromatographim;lss spectrophotometer to determine the individual amounts of water and VOC adsorbed on an ACC sample. RH values from 0 to 90% and organic concentrations from 350 to 1000 ppmv were examined. The presence of water vapour in the gas stream along with acetone (350 and 500 ppmv) had little effect on the adsorption capacity of acetone even at 90%~ RH. Water vapour in the gas stream had little effect on the adsorption capacity of benzene (500 ppmv) until about hSP/r RH, when a rapid decrease resulted in the adsorption capacity of benzene with increasing RH. This RH was also about where capillary condensation of water vapour occur\ within ACC pores. Water vapour condenses within the ACC pores, making them unavailable for benzene adsorption. Increasing benzene concentration can have a significant effect on the amount of water vapour adsorbed. At Xh6d RH and 500 ppmv, 2X4 mgig water was adsorbed, while at 86% RH and IO00 ppmv, only lh5 mgig water was adsorbed. Water vapour was more inhibitory for benzene adsorption as benzene concentration in the gas stream decreased.

97lOO310 IGCC

Startup

of large-scale

projects

casts

spotlight

on

Swanekamp, R., Power, 1996, 140. (6), S9-ho, 62. 64-65. 67-68. This review considers the large-scale demonstration plants using Integrated gasification combined cycle (IGCC) technology. Also discussed are types of gasifier, heating value of the syngas, particle removal system, carbon dioxide emission, using petroleum coke or refinery residues as feedstock. and waste treatment.