摘要:

This work investigates the coprocessing of coal in six different heavy petroleum crudes and residua. Coprocessing reactions of coal and the petroleum solvents are performed under three sets of constant reaction conditions, yielding informative comparative data for processing applications. Definitive comparisons of coal reactivity and solvolysis in the petroleum solvents have been obtained using solvent fractionation which provides a measure of the degree of upgrading achieved by the liquefied coal. Regressive reactions and low coal conversions are observed in coprocessing reactions in N2at 400°C. Higher conversions and a reduction in regressive reactions are observed in H2at 400°C. Catalytic hydrotreatment and higher temperature, 425°C, result in increased coal conversion and a net production of pentane soluble materials. The amount of product fractions obtained from the upgrading of the coal alone is calculated. The effect of reaction temperature using different solvents and reaction conditions on the product slate is also examined.

ISSN:0884-3759    

DOI:10.1080/08843758708915854

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The organic chemical substances present in UCG- affected subsurface waters are formed by the thermal degradation of coal. After a UCG reactor is shut down, the sensible heat contained in the rubble pile is sufficient to continue coa1 pyrolysis. If the pyrolysis products are not removed. they become a potential source of sub surface water contamination. Heat transfer into the coal seam and migration c if chemical substances after reactor shutdown can be sub stantially reduced by a controlled influx of water through the cavity side wal1s and removal of produced fluids from the reactor.

ISSN:0884-3759    

DOI:10.1080/08843758708915855

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The results of the thermal and catalytic reactions of lignin model compounds are used in thea prioriprediction of its liquefaction. Lignin was defined probabilistically as an ensemble of single ring aromatics with substituents on each of their six ring positions. Elements in a substituent vector x1, for each ring position i, were matched into all possible combinations to describe lignin. Initial number fractions, or probabilities, for each vector element were ascertained through inspection of lignin structural data. The reaction of lignins altered the probabilities within each substituent vector, and reaction products were also calculated by matching all combinations of vector elements for each ring position. Model compound results provided the identities and rates of change of vector elements.

ISSN:0884-3759    

DOI:10.1080/08843758708915856

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Inorganic constituents present in UCG process effluents can be strongly correlated with changes in coal and overburden mineralogy. An analysis of the Hanna, Wyoming, UCG site provides insight on how inorganic constituents enter the system. A comparison of preburn versus postburn mineralogy indicates that carbonates, clay minerals, micas, and sulfurous minerals break down structurally because of high temperatures. This decomposition releases calcium, magnesium, silica, and aluminum for rebonding in high-temperature stable silicate and al um1 nosi1icate minerals. It also releases constituents such as iron, sodium, sulfur, and boron into the UCG process effluent. Other constituents such as calcium, copper, magnesium, manganese, potassium, and sodium are predominantly introduced into the groundwater by leaching. Groundwater quality data and analyses of other process effluents support these interpretations. Complete chemical and mineralogical characterization of the coal, coal ash, and immediate overburden is an important tool in determining inorganic constituents that affect groundwater quality at UCG sites. Early planning offers substantial economic incentives by allowing treatment while the constituents are confined to the cavity before migration affects much larger areas.

ISSN:0884-3759    

DOI:10.1080/08843758708915857

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The effect of two iron catalysts, red mud and CGS S-G, as well as C0-Mo/AI2O3 and Ni-Mo/Al203 commercial catalysts on the composition of oil derived from the liquefaction of Japanese subbituminous coal have been investigated comparatively by conventional autoclave experiments at 440 and 450°C under initial hydrogen pressure of 85kg/cm2G with tetralin to coal weight ratio of 3. From the results obtained at 450°C, total conversion and the yield of gas revealed almost same level with four catalysts, but the oil product from molybdenum catalysts showed higher yield than that from iron catalysts. CGS S-G catalyst also showed higher yield of oil product than red mud catalyst. Reaction behavior of two iron catalysts were also tested by solvent recycle mode experiments.

ISSN:0884-3759    

DOI:10.1080/08843758708915858

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor