As the cost of production is a key determinant of longterm viability, developing methods that reduce the cost of direct coal liquefaction has posed a challenge to scientists and industrial organizations worldwide. This paper summarizes recent developments in technology and processes and explores the overall economic competitiveness of direct coal liquefaction using the China Shenhua Group ...
Direct Coal Liquefaction (DCL) commonly refers to catalytic hydrogenation of coal in a recycled oil solvent at high pressures with a catalyst. While a range of process configurations have been proposed, the most common version involves at least two high pressure slurry reactors in a series using a dispersed ironbased catalyst and hydrogen ...
Coal. Direct coal liquefaction (DCL) and indirect coal liquefaction (ICL) are the two prominent processes for coaltomethanol conversion. DCL primarily involves thermal breaking of the polymeric coal structure at elevated temperatures with subsequent hydrogenation of the fragments to generate lighter molecules.
When considering the development of coal liquefaction process using syngas, in addition to the above typical processes, hydrothermal liquefaction process is a technology worthy of reference. Hydrothermal liquefaction [110], [111], [112] is an effective and emerging technology that can convert both coals and biomass containing high moisture ...
The environmental footprint of coal liquefaction processes can usually be reduced by coprocessing ... [18], [19]. In addition, utilization of biomass in the DCL process can reduce the external hydrogen demand in ... the carbon footprint of the energy conversion processes can be reduced by adding biomass and applying CCS technologies at the ...
The use of highcarbonbased feeds to produce alternative fuels and valueadded chemicals is discussed. Basic conversion chemistry, chemical structures of coal and lignin biomass are discussed, followed by process technologies for direct liquefaction, liquid quality, process control and modeling, advantages and limitations, and future trends.
The use of highcarbonbased feeds to produce alternative fuels and valueadded chemicals is discussed. Basic conversion chemistry, chemical structures of coal and lignin biomass are discussed, followed by process technologies for direct liquefaction, liquid quality, process control and modeling, advantages and limitations, and future trends.
Various metal compounds have been used to catalyze the process. This type of CTL technology is called direct coal liquefaction (DCL). DCL technology involves making a partially refined synthetic crude oil directly from coal, which is then further refined into synthetic gasoline and diesel as well as liquefied petroleum gas (LPG).
Direct coal liquefaction (DCL) is a promising technology to convert coal into oil, especially for countries where coals dominate fossil energy resources [1]. ... Coal utilization processes and their application to waste recycling and biomass conversion. Fuel (1994) Wang et al. ... were prepared by a solidstate insitu impregnation and ...
The Energy and Environmental Research Center (EERC), in partnership with the Department of Energy (DOE) and Accelergy Corporation, an advanced fuels developer with technologies exclusively licensed from ExxonMobil, undertook Subtask to design, build, and preliminarily operate a benchscale direct coal liquefaction (DCL) system capable of converting 45 pounds/hour of pulverized, dried ...
For the most highly developed processes, coal conversion can be as high as 90% on a mineral ash free basis, with a C 5+ distillate yield up to 75% and hydrogen consumption of 57% wt. When an external catalyst is used, it is typically some combination of cobalt, nickel, and molybdenum on a solid acid support such as silicaalumina [].In slurry hydrogenation processes, catalyst lifetime is ...
Other thermochemical conversion technologies are under development for coprocessing biomass and fossil fuels. During the coliquefaction of coal with biomass, lower liquefaction temperature of coal and higher liquid products yield than those predicted by mathematic models are obtained as a result of the synergetic effect.
The decomposition process in coal liquefaction is consisting of pyrolysis, solvent extraction and liquefaction processes directly or indirectly [2] [3][4]. The pyrolysis reaction is a complex ...
The environmental footprint of coal liquefaction processes can usually be reduced by coprocessing coal and biomass and applying CO 2 capture and storage (CCS) technology but at the cost of higher ...
To meet future demand in motor fuels, coal will play a key role in areas with large coal resources and lacking crude oils. Axens' direct coal liquefaction (DCL) process is available to produce ...
The growing demand for petroleum, accompanied by the declining petroleum reserves and the concerns over energy security, has intensified the interest in direct coal liquefaction (DCL), particularly in countries such as China which is rich in coal resources, but short of petroleum. In addition to a general introduction on the mechanisms and processes of DCL, this paper overviews some recent ...
Direct coal liquefaction (DCL) commonly refers to catalytic hydrogenation of coal in a recycled oil solvent at high pressures with a catalyst. While a range of process configurations have been proposed, the most common version involves at least two high pressure slurry reactors in a series using a dispersed ironbased catalyst and hydrogen ...
There are many liquefaction processes related to DCLS [26], [29], [31], [108], [109]. Several typical or highly referential liquefaction processes that have been reported are selected in this paper for introduction. As an illustration, a flow diagram of coal liquefaction process using syngas was proposed by Fu et al. [29], as shown in Fig. 14.
ICL includes two steps; in the first step, coal is converted into syngas ( Coal+H2OCO+H2), and during the last step, syngas is synthesized in the presence of a catalyst into liquid fuels.
The term ''coaltoliquids'' (CTL) refers to conversion of solid coal into liquid fuels and chemicals through either of two principle,11 Direct coal liquefaction (DCL) involves ...
Coal can also be liquefied directly into liquid fuels through direct coal liquefaction (DCL) processes at around 450500 °C under 1530 MPa H 2 in a suitable solvent with appropriate catalysts [2,3,4,5,6,7,8,9]. In many processes, the solvent used can facilitate the heat and mass transfer during chemical reactions, and function as a ...
There remains an important need for economical coal and biomass to liquids conversion processes with reduced carbon dioxide emissions and efficient use of carbon resources. ... 1—CO 2 carbon capture and conversion to a biological material such as algae; 2—direct coal liquefaction (DCL); 3—indirect conversion of biomass and/or coal to ...
catalyst in the DCL of Shenhua coal at 400 °C. and MPa H. 2. resulted in a coal conversion and (gas + oil) yield, up to % and %, respectively, much higher than those obtained with FeS ...
The liquefaction process of coal and biomass materials, which is known as "Coliquefaction", has not been developed in Malaysia. The yields and quality (especially H/C ratio) of the liquid products obtained from coal under less severe liquefaction conditions (at lower temperature and pressure) can be improved with coliquefaction of coal ...
Direct liquefaction (DCL) processes and technology for coal and biomass conversion
In this process, coal with moderate amount of biomass is converted into syncrude through reaction with Hdonor solvent and gaseous hydrogen in a catalytic twostage liquefaction unit.
For the most highly developed processes, coal conversion can be as high as 90% on a mineral ash free basis, with a C 5+ distillate yield up to 75% and hydrogen consumption of 57%wt. When an external catalyst is used, it is typically some combination of cobalt, nickel, and molybdenum on a solid acid support such as silicaalumina [].DCL process concepts have been based on a variety of ...
Headwaters direct coal liquefaction process. Source: Headwaters. Click to enlarge. Headwaters Inc and Axens are forming a strategic alliance to provide a singlesource solution for producing synthetic fuels by direct coal liquefaction (DCL) alone or in combination with refinery residues or biomass. The two companies will combine their technologies and...
Abstract: This chapter focuses on liquefaction of solids, primarily coal and biomass sources such as lignin. In a twostep process the molecular structure is broken into fragments and hydrogenated, increasing the hydrogentocarbon ratio and preventing retrogressive reactions. Solvents solubilize smaller molecular weight components and promote hydrogenation; catalyst improves hydrogenation ...
The results showed the price of coal had a more dominant effect on RSP than that of biomass. Different mix ratios and conversion rates led to RSP ranging from /bbl. LCA results indicated that GHG emissions ranged from kg CO2 eq to kg CO 2 eq/1000 MJ of liquid fuel at various biomass to coal mix ratios and ...
To improve the performance of megaton direct coal liquefaction (DCL) technology that has been practiced in China since 2008 and to develop a better technology that can be operated at milder conditions with high efficiency, this work studies coal conversion (X C), products yield (Y i) and hydrogen consumption (R H) of SW coal (H/C = ) used in the megaton plant and NMH coal of a higher H/C ...
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