[en] Main properties of brown coals in Karazhyra open pit upper and lower packs are determined. Characteristics of these coals briquette-ability are evaluated. A conceptual possibility to obtain high-quality briquettes from open pit coal fines is shown. (author)

[en] Bechtel, together with Amax Research and Development Center (Amax R ampersand D), has prepared this study which provides conceptual cost estimates for the production of premium quality coal-water slurry fuel (CWF) in a commercial plant. Two scenarios are presented, one using column flotation technology and the other the selective agglomeration to clean the coal to the required quality specifications. This study forms part of US Department of Energy program Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications, (Contract No. DE-AC22- 92PC92208), under Task 11, Project Final Report. The primary objective of the Department of Energy program is to develop the design base for prototype commercial advanced fine coal cleaning facilities capable of producing ultra-clean coals suitable for conversion to stable and highly loaded CWF. The fuels should contain less than 2 lb ash/MBtu (860 grams ash/GJ) of HHV and preferably less than 1 lb ash/MBtu (430 grams ash/GJ). The advanced fine coal cleaning technologies to be employed are advanced column froth flotation and selective agglomeration. It is further stipulated that operating conditions during the advanced cleaning process should recover not less than 80 percent of the carbon content (heating value) in the run-of-mine source coal. These goals for ultra-clean coal quality are to be met under the constraint that annualized coal production costs does not exceed $2.5 /MBtu ($ 2.37/GJ), including the mine mouth cost of the raw coal. A further objective of the program is to determine the distribution of a selected suite of eleven toxic trace elements between product CWF and the refuse stream of the cleaning processes. Laboratory, bench-scale and Process Development Unit (PDU) tests to evaluate advanced column flotation and selective agglomeration were completed earlier under this program with selected coal samples. A PDU with a capacity of 2 st/h was designed by Bechtel and installed at Amax R ampersand D, Golden, Colorado by Entech Global for process evaluation tests. The tests successfully demonstrated the capability of advanced column flotation as well as selective agglomeration to produce ultra-clean coal at specified levels of purity and recovery efficiency. Test results and the experience gained during the operation of the PDU have provided valuable insights into the processes studied. Based on the design data obtained from the test work and a set of project design criteria, two sets of conceptual designs for commercial CWF production plants have been developed, one using column flotation and the other using selective agglomeration process. Using these designs, Capital as well as Operating and Maintenance (O ampersand M) cost estimates for the plants have been compiled. These estimates have then been used to derive the annualized cost of production of premium CWF on a commercial scale. Further, a series of sensitivity analysis have been completed to evaluate the effects of variations in selected cost components and process parameters on the overall economics of premium fuel production

[en] The objective of this research project is to develop an aqueous biphase extraction process for the treatment of fine coals. Aqueous biphase extraction is an advanced separation technology that relies on the ability of an aqueous system consisting of a water-soluble polymer and another component, e.g., another polymer, an inorganic salt, or a nonionic surfactant, to separate into two immiscible aqueous phases. The principle behind the partition of solid particles in aqueous biphase systems is the physicochemical interaction between the solid surface and the surrounding liquid solution. In order to remove sulfur and mineral matter from fine coal with aqueous biphasic extraction, it is necessary to know the partitioning behavior of coal, as well as the inorganic mineral components. Therefore, in this research emphasis was placed on the partitioning behavior of fine coal particles as well as model fine inorganic particles in aqueous biphase systems

[en] The paper discusses, in the context of Zambia's Energy Policy, the impact of substituting woodfuel with fossil fuels like Coal on Greenhouse gases, mainly CO2.Computation of comparative emissions of CO2 by implementing this energy substitution especially at household level is presented. Further, the processing of Coal into Briquettes is discused. 2 figs., chart

[en] The Calla Energy Biomass Project, to be located in Estill County, Kentucky is to be conducted in two phases. The objective of Phase I is to evaluate the technical and economic feasibility of cofiring biomass-based gasification fuel-gas in a power generation boiler. Waste coal fines are to be evaluated as the cofired fuel. The project is based on the use of commercially available technology for feeding and gas cleanup that would be suitable for deployment in municipal, large industrial and utility applications. Define a combustion system for the biomass gasification-based fuel-gas capable of stable, low-NOx combustion over the full range of gaseous fuel mixtures, with low carbon monoxide emissions and turndown capabilities suitable for large-scale power generation applications. The objective for Phase II is to design, install and demonstrate the combined gasification and combustion system in a large-scale, long-term cofiring operation to promote acceptance and utilization of indirect biomass cofiring technology for large-scale power generation applications. During this Performance Period work efforts proceeded, and Carbona completed the gasifier island design package. Nexant has completed the balance of plant support systems design and the design for the biomass feed system. Work on the Technoeconomic Study is proceeding. Approximately 75% of the specified hardware quotations have been received at the end of the reporting period. A meeting is scheduled for July 23 rd and 24 th to review the preliminary cost estimates. GTI presented a status review update of the project at the DOE/NETL contractor's review meeting in Pittsburgh on June 21st

[en] Efficiency of pulverized coal injection (PCI) at two blast furnaces (BFs) in Spain and Ukraine which operate at different burden and blast conditions has been analyzed using statistical methods, calculation of material and heat balances and mathematical model. Effect of PCI on the parameters of blast furnace operation, pig iron quality and also on interactions between process parameters has been studied. At high-grade burden and high parameters of the combined blast, dependence of coke consumption rate on PC amounts is linear up to a high rate of PCI. At unfavorable burden and technological conditions dependence of the main furnace operating parameters on PC rate has extreme character. High efficiency of PC use can be achieved at the different conditions due to optimization of the technological regime. (Author) 31 refs

[en] Injection rate of fossil fuels is limited because of drop in the flame temperature in the raceway and problems in the deadman region and the cohesive zone. The next step for obtaining a considerable coke saving, a better operation in the deadman as an well as increase in blast furnace productivity and minimizing the environmental impact due to a decrease in carbon dioxide emission would be injection by tuyeres of hot reducing gases (HRG) which are produced by low grade coal gasification or top gas regenerating. Use of HRG in combination with high pulverized coal injection PCI rate and oxygen enrichment in the blast could allow to keep and to increase the competitiveness of the blast furnace process. Calculations using a mathematical model show that the HRG injection in combination with pulverized coal (PC) and enriching blast with oxygen can provide an increase in PC rate up to 300-400 kg/tHM and a rise in the furnace productivity by 40-50% Blast furnace operation with full oxygen blast (100 % of process oxygen with the exception for the hot blast) is possible when HRG is injected. (Author) 54 refs

[en] The overall objective of this project is to improve the efficiency of fine coal cleaning. The project will be completed in two phases: bench-scale testing and demonstration of four advanced flotation cells and; in-plant proof-of-concept (POC) pilot plant testing of two flotation cells individually and in two-stage combinations. The goal is to ascertain if a two-stage circuit can result in reduced capital and operating costs while achieving improved separation efficiency. The plant selected for this project, Cyprus Emerald Coal Preparation plant, cleans 1200 tph of raw coal. The plant produces approximately 4 million tonnes of clean coal per year at an average as received energy content of 30.2 MJ/Kg (13,000 Btu/lb)

[en] Highlights: : • Ferroferric oxide@N-doped residual carbon (Fe₃O₄@NRC) composites were successfully fabricated. • The widest absorption bandwidths can cover 4.32 GHz at 1.5 mm thickness. • Strong absorption, broad bandwidth and thin thickness were simultaneously achieved. • The reasons of high-performance microwave absorption are studied. -- Abstract: Residual carbon (RC) from entrained-flow coal gasification fine slag is formed with graphitized structure after high-temperature gasification of pulverized coal. Here, ferroferric oxide@N-doped residual carbon (Fe₃O₄@NRC) composites were successfully fabricated by decorating RC with Fe₃O₄ nanoparticles via a facile chemical coprecipitation method. The structure, morphologies, thermal stability, chemical compositions, and related electromagnetic (EM) parameters of the RC and as-prepared Fe₃O₄@NRC with different filler loadings were characterized by using various analytical techniques. The RC shows a certain EM wave (EMW) absorption ability. The Fe₃O₄@NRC composites exhibit excellent EMW absorption performance. When 40% mass was added, the minimal reflection loss (RL_min) value of Fe₃O₄@NRC is − 41.4 dB, and the effective absorption bandwidth (RL≤−10 dB) is up to 4.32 GHz (13.6818 GHz) at a thickness of 1.5 mm. The EMW absorption ability of Fe₃O₄@NRC can be tailored by controlling the filler loading composites. The well-matched dielectric loss and magnetic loss result in the enhancement of EMW absorption performance of Fe₃O₄@NRC composites. The magnetic carbon composites display an excellent EMW performance, thereby promoting the by-product utilization of coal gasification.

[en] Fly ash is the end product of coal combustion and coal. Like most earthen materials it contains ²³⁸U the parent element of the uranium decay series which support several radioactive decay products including radon. Radon exhalation rate from fly ash produced by thermal power station has been measured and compared with that from different kinds of soil and from coal itself. It is observed that the radon exhalation rate from fly ash is less than that from soil and coal, although fly ash contains a higher concentration of uranium than typical soil. (author)