The influence of aggregate and binder phase characteristics on formcoke products has been studied. This involved investigating the compaction kinetics of the system and determining the mechanical strength of the briquettes produced. The char phase was characterized in terms of density, hardness, porosity and residual volatile matter content and the rheological properties of the binder phases used were established elsewhere. The strength and wetting behaviour of the aggregate-binder interface were studied using model materials (an SRC pitch binder and a graphite rod aggregate) as well as those produced in this work. Analysis of compaction curves was carried out using the CCWL Hot Compaction Model for Char-Binder Coal systems which was found to adequately describe the observed compaction behaviour. Briquette strength was characterized by ultimate compressive strength and comparisons were made for a constant briquette bulk porosity of 35% (by volume). Results indicate that binder phase fluidity affects compaction viscosity during the particle flow stage of compaction and that char porosity influences final briquette bulk density by affecting the amount of total compaction required to obtain a given bulk density. In general, increased total compaction was shown to result in higher product bulk density and high bulk density was found to yield higher gross composite strength. The latter relationship was seen to be approximately linear over the range of bulk porosity encountered in this study. A higher briquette strength was found for systems with aggregates carbonized at lower temperatures. This was attributed to a combination of higher porosity and stronger char-binder interfacial strength, although the former effect was considered to predominate in the systems considered here. Binder phase fluidity was also seen to affect briquette strength, higher fluidity resulting in higher strength. It was concluded that this was due to increased binder penetration of the aggregate phase. With no significant pore structure in the aggregate, as found with high temperature char, briquette strength was seen to become approximately constant for the three binder coals used. It was concluded that a good formcoke product was aided by a highly fluid binder and a char pore structure accessible to the binder phase. / Applied Science, Faculty of / Materials Engineering, Department of / Unknown

No description available.

Thesis (Ph. D.)--Columbia University, 1931. / Vita. "Authorized preprint from copyrighted articles in Gas age-record, volume 68, numbers 5, 6, and 7, August 1, 8, and 15, 1931." Bibliography: p. 35.

Thesis. 1978. Sc.D.--Massachusetts Institute of Technology. Dept. of Chemical Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 382-396. / by Eric M. Suuberg. / Sc.D.

Coal is one of the world's largest remaining mineral resources. The supply of this rich source of fuel and chemicals is sufficient to serve the world for several thousand years. Coal is used directly and is also heat treated at high and low temperatures to produce fuel and by-products. Of the several methods of treatment that can be used, low-temperature carbonization is one of the most promising. Nearly all of the coke and coal chemicals produced today come from the production of high temperature coke. However, there are many lower rank coals not suited for metallurgical purposes that will produce an excellent char and high yields of by-products. One of the disadvantages of many lower rank coals is their tendency to swell and become plastic when heated to carbonization temperatures, and this property has to a great extent made the operation of the retorts difficult. In an effort to reduce or circumvent this undesirable property, several methods of pretreating the raw coal have been tried including preoxidation, dilution with non-coking coal, preheating, and weathering. The type and severity of the pretreatments vary in their effects on the coking properties of different coals. The purpose of this investigation was to study the effect of preoxidation on the coking properties and the quantities and composition of the byproducts and char obtained from the low-temperature carbonization of Penn-Lee coal. / Master of Science

No description available.

This thesis reports a study on the effects of size distribution, moisture content and oil addition on bulk density and angle of repose of coal. The experimental work includes four stages. The first stage is to develop reliable experimental techniques. The results confirm that ASTM cubic foot test is reliable for measurement of bulk density and angle of repose if properly operated, although the latter is better measured in a piling process. Stages 2 and 3 are to investigate the effects of size distribution by using -3.55mm% for stage 2 and mean size do.s for stage 3, water content and oil addition on bulk density and angle of repose of coal. For each of them, empirical equations are formulated to predict bulk density and angle of repose. The results indicate that the fraction -3.55mm cutting size in stage 2 does not affect bulk density significantly, while the increase of do.s decreases bulk density to a minimum and then increases. Particle size distribution does not affect angle of repose much. The increase of moisture content decreases bulk density and increases angle of repose significantly. The increase of oil addition increases bulk density while decreases angle of repose significantly. The correlation between bulk density and angle of repose can also be observed: the higher bulk density, the lower angle of repose. There are other variables affecting bulk density and angle of repose. They include oil type, absorption time discharging height and external loading. Their effects on bulk density and angle of repose are quantified in stage 4. The results suggest that, a higher discharging position or larger external loading increase bulk density significantly. Angle of repose decreases when increase the height of discharging position. Diesel oil performed better than waste oil addition in terms of bulk density enhancement. For most of the cases examined, bulk density and angle of repose become stable after ~24 hours oil absorption time.

The purpose of this investigation was to study the factors affecting the low-temperature carbonization of seam number one, Penn-Lee coal from southwestern Virginia, by determining the effect of pretreatment of the charge, temperature of the retorting gas, and time of retorting on the yields and properties of the products of carbonization. After an examination of the literature pertinent to the investigation, a pilot-scale carbonization unit was constructed. The construction of the unit consisted partly of the modification of an existing fluidization unit. Various auxiliary apparatus were also added to the modified unit for more satisfactory operation. A series of bench-scale tests were performed to study the effect of pretreatment conditions on the free-swelling index, the weight loss, and the volatile matter in Penn-Lee coal. Time and temperature had a significant effect upon the free-swelling index. Temperature of pretreatment had a significant effect on the weight loss during pretreatment. Time and the time by temperature effect were found to be significant with regard to the volatile matter remaining in the coal after pretreatment. Also, the decomposition point of Penn-Lee coal was found to lie between 427 and 454 °C (800 and 850 °F). Twelve pilot-scale tests were performed to study the effect of carbonizing conditions on the products of carbonization. The pretreatment time had a significant effect upon the dry tar yield, the tar viscosity, the tar specific gravity, and the twenty per cent tar distillation temperature. The time of carbonization had a significant effect upon the gas yield. None of the variables studied showed a significant effect within the range studied, upon the volatile matter in the char product, the bulk density of the char, or the calorific value of the char. / Ph. D.

Thesis (MBA)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: It was found that the hot metal cost of ISCOR Newcastle's single blast furnace can significantly be reduced by the correct use of an integrated model to predict reductant cost based mainly on coal blend. The model uses coal ash chemistry, fluiidity, vitrinite rank and volatile matter to predict coke strength after reaction (CSR), coke ash and coking yield. CSR is used to predict maximum allowable coke nut- and pea consumption in the furnace as well as hot blast temperature. Pitch injection levels are predicted using CSR and blast furnace production rates. Coke ash, pitch injection and hot blast temperature is used to predict the coke rate. The above is used with imported Chinese coke cost to accurately predict reductant cost. It was found that the current optimum blends should include Australian en Nieu Zeeland coals because of price and quality conciderations. Because of its low cost of production and low quality the optimum percentage of Grootegeluk in the blend is determined largely by its transfer price. / AFRIKAANSE OPSOMMING: Die vloeiyster koste van ISCOR Newcastle se enigste hoogoond kan drasties verlaag word deur die korrekte gebruik van 'n geïntegreerde model wat reduktant koste voorspel op grond van steenkoolmengsel. Die model gebruik die chemiese samestelling van steenkool-as, fluiiditeit, vitriniet rang en vlugstof om kooks warmsterkte (SNR), kooks-as en verkooksingsopbrengs te voorspel. SNR is gebruik om die maksimum kooksneute- en -erteverbruik in die hoogoond sowel as blaastemperatuur te voorspel. Pikinspuiting is bereken met SNR en hoogoond produksietempo's. Pikinspuiting en blaastemperatuur word saam met kooks-as gebruik om kookskoers te voorspel. Bogenoemde is saam met die koste van ingevoerde Chinese kooks gebruik om reduktant koste akkuraat te voorspel. Daar was bevind dat die huidige optimum mengsels Australiese en Nieu Zeelandse steenkool moet bevat as gevolg van huidige prys- en kwaliteitsoorwegings. As gevolg van sy lae produksiekoste en lae kwaliteit word die optimum hoeveelheid Grootegeluk bepaal deur sy oordragprys.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Bibliography: leaves 594-611. / Sc.D.