76
Fuel science and technology
(fundamental
science, analysis, instrumentation)
model and a Monte-Carlo radiation sub-model. The model was applied to simulate the performance characteristics of the two gasifiers (2 and 200 tons/day) so far tested in Japan. The model predicted the effects of air/coal ratio, coal and air partition between combustor and reductor on the gasifier performance, such as the carbon conversion, the cold gas efficiency and heating value of the product gas. Between the predictions and the test measurements good agreement was obtained.
Mechanism of adsorption species on activated carbons
99100800
of gold
and silver
Jia, Y. F. et al. Carbon, 1998, 36, (9). 1299-1308. Investigated were the adsorotion characteristics of eold and silver cvanide anionicspecies on a suite of’active carbons derived f;om coal, coco& shell and polyacrylonitrile. The gold and silver cyanide adsorption capacities for both- cdconut shell and coal derived carbons correlate with total pore volume. Treatment of the carbon with nitric acid was detrimental to gold adsorption in spite of the incorporation of oxygen into the carbon through oxidation. Also investigated was the influence of nitrogen functional groups in the carbon structure on gold and silver adsorption using carbons with very high nitrogen contents derived from polyacrylonitrile. An adverse effect on gold adsorption was produced by the addition of ethanol and butanol to the solution. Adsorption of silver cyanide ionic species on the active carbon was suppressed in the presence of excess free cyanide ions in solution whereas gold cyanide adsorption was not greatly affected. The results are discussed in terms of the mechanism of adsorption, equilibria in solution and the bonding in metal cyanide complexes adsorbed on the carbon surface.
99/00801 Method for removing oil from semi-water gas by filtration using coke Chen, J. and Wang, M. CN 1,12X251 (Cl. ClOKl/lO), 26 Jun 1996, Appl. 95,112,489, 16 Ott 1995; 6 pp. (In Chinese) The semi-water gas is passed downwardly through a filter having coke layer to remove the oil components from the gas, then periodically washing the coke layer using waste hot water and gas for regeneration.
The Novacon process: a new class of sorbent 99/00802 technology Baer. S. H. and Luftelass. B. K. Proc. Inr Conf Fluid. Bed Cornbust. 1997, 14. (il. 1095-1101. A ‘nk\;\y-introduced class of sorbent useful for decreasing sulfur dioxide (802) emissions in circulating fluidized bed (CFB) boilers is discussed in this paper. The sorbent, called ‘thermally active marble (TAM)‘, includes a class of naturally recrystandard, metamorphic calcium carbonate (CaC03) products which range in purities from at least 54-98% CaC03 and have thus far been found in numerous locations. TAMS break down upon heating more evenlv and with higher reactivities than limestone because of their physical properties, res&ing in better calcium utilization rates. Calcium/ sulfur ratios and tonnage feed rates have improved by up to 40% in commercial demonstrations compared with conventional limestones. The introduction of TAMS also causes significant changes in the combustion environment, which has been shown to lead to a-reduction in nitrogen oxides (NO,) and carbon monoxide (CO), as well as better carbon burnout in fly ash and bed ash. The results of tests of TAMS in pilot scale and commercial scale CFB boilers are described. Briefly presented are findings from testing in other boiler applications, including a pulverized coal boiler simulator,
Operational nitrlfication system
99lOO803
control
of coke
plant
wastewater
Bhattacharyya, A. et al. Iron Steel Eng., 1998, 75, (5). 30-33. To achieve trouble-free operation of an activated sludge nitrification system for the treatment of coking facility wastewater, Microtox test was used. Examples of the use of the Microtox test in the improvement of the wastewater treatment system are reported.
99100804 Performance of black liquor asifler/gas turbine combined cycle cogeneration in the kraa pulp and paper industry _ -
using four different black liquor gasifiers modelled on proposed commercial designs. A range of process steam demand levels are considered, including supplemental biomass firing in a boiler when needed.
Powdered fuel compositions for manufacture of cement clinkers
99/00805
Naito, H. and Hon, H. Jpn. Kokai Tokkyo Koho JP 10 121,076 [98 121.0761 (Cl. ClOL7/02), 12 May 1998, Appl. 96/276,734, 21 Ott 1996; 5 pp. (In Jaoanese) Powddred cornpositive for manufacture of cement clinkers contain (A) 100 wt parts powdered support of phyllosilicate clay minerals containing threelayered dioctahedral montmorillonite clay minerals as main component and <14 wt% water and (B) 15-60 wt parts liquid fuels, which the powdered compositions pass 50 mesh screen. 99/00806
sulfidation pressures
Product layer development during sulfation and of uncalcined limestone particles at elevated
Zevenhoven, C. A. P. et al. Ind. Eng. Chemical Res., 1998, 37, (7), 26392646. Fluidized bed gasification or combustion allows for in-bed sulfur capture with a calcium-based sorbent such as limestone or dolomite. Sorbent particle size, porosity, internal surface, and their variation during conversion have great influence on the conversiopressurized fluidized be8 combustor or gasifier conditions: 850/950”, 15/20 bar. It is stressn of the sorbent. Discussed is the uptake of SO* and H# by five physical different limestones, for typical ed that the limestones remain uncalcined. A changing internal structure (CIS) model is presented in which reaction kinetics and product layer diffusion are related to the intraparticle surface of reaction. The random pore model was used for describing the changing internal pore and reaction surfaces. Rate parameters were extended for all five limestones using the CIS model and a USC model with variable effective diffusivity. Differences in the sulfur capture performance of the limestones were evaluated. Plots of the CaS04 or CaS product layer thickness as a function of conversion are given, and the relative importance of limestone porosity and internal surface is discussed. 99iOO807 The R W Miller Mount Thorley project 19761988 Davies, E. Publ. Ausrralas. Inst. Min. MeraN., 1998, 2, 15-26. R W Miller & Co Pty Ltd operated old coal properties abandoned by former owners as uneconomic, some of which dated back to the last century for over 50 years. The company’s ability to survive with what were relatively poor quality coal resources required a small efficient management organization. In November 1976 R W Miller was granted Authorisation 66 of 2167.5 ha at Mount Thorley near Singleton. The development of this coal mining project coincided with the second OPEC oil crisis in 1978 and a short-term boom for coal resources and the unrealistic expectations generated by the boom. This paper gives a broad outline of the development of the Mount Thorley project between 1976 to 1986 including the feasibility study and the many~g&&nmental and industrial delays that resulted in a three-year time overrun in the project development period. 99iOO808
A reliable and economical
route for coal based
DRI production Duarte, P. E. et al. Ironmaking Conf. Proc., 1998, 57, 891-898. Three companies, Texaco, HYL and their licensee FS, have been working on plant design for an approach based on a gasifier for carbonaceous material feeding syngas to a standard HYL III DR module. Compared to other technologies this scheme presents low production cost per tonne of liquid steel. Main reasons are production of hot DRI (HYTEMP system), optimization on gasifier size and operation mode, use of low-grade fuels with no influence on DRI quality, uniform steel qualities, minimal environmental impact, etc. An important characteristic of this approach is the commercial proven Texaco gasifier combined with an HYL DR module with no change in the standard process schemes. As compared to other existing and emerging coal-based DR technologies, this scheme offers the flexibility to install a DR plant of any size from 0.40 up to 1.35 million tonnes/year of DRI in a single module. In this paper the focus is on the technology solution for the combination of Texaco coal gasifier and the HYL DR plant.
Research and development on new synthetic routes for basic chemicals by catalytic hydrogenatlon of CO*
Larson,
99100809
Edited by Overend, R. P. and Chornet, E. Pulp and paper production worldwide is dominated by the kraft process. Black liquor, a mixture of lignin and inorganic chemicals, is generated in this process as fibre is extracted from wood. At most kraft mills today, black liquor is burned in Tomlinson boilers to produce steam for on-site heat and power and to recover the in-organic chemicals for reuse in the process. Globally, the black liquor generation rate is about 85,000 MWrucl, with nearly 50% of this in North America. New kraft production capacity is being added most rapidly in Brazil, Indonesia, and other regions with low wood production costs and relatively low per-capita levels of paper use. As a replacement for Tomlinson-based cogeneration, black liquor-gasifier/gas turbine cogeneration promises higher electric efficiency, with prospective environmental, safety, and capital cost benefits for kraft mills. Several companies are pursuing commercialization of black liquor gasification for gas turbine applications. The results of detailed performance modelling of gasifier/gas turbine combined cycle systems are presented in this paper
Arakawa, H. Stud. Surf Sci. Catal., 1998, 1, (14), 19-30. This paper covers recent studies on catalytic hydrogenation of CO2 to various kinds of valuable chemicals and fuels, including CO* hydrogenation as a possible countermeasure against global warming caused by CO2 emission; advances in the effective syntheses of methanol, di-Me ether, ethanol, lower paraffins, lower olefins, gasoline fraction, formic acid, acetic acid and other chemicals; and the progress in solar hydrogen production for CO2 fixation.
E. D. and Consonni, S. Making Bus. Biomass Energy, Environ., Chemical, Fibers Mater., Proc. Biomass Conf. Am., 3rd, 1997, (2), 1495-1512.
80
Fuel and Energy Abstracts
January 1999
Research on a new type of addltive for CWS from low temperature pyrolysis tar _-
99/00810
Wu. G. and Wang, Z. Proc. Annu. Int. Pittsbutxh Coal Conf., 1997, 14, (23j, 1-7. In this paper, in the synthesis of an additive for coal water slurry (CWS) in the laboratory, coal tar from flash pyrolysis of Ping Zhuang lignite with solid heat carrier was used. The heat of wetting of the lignite with distilled