these biomass resources in one or the other way. With very few exceptions, all conversion processes for biomass produce solid, liquid, and gaseous products in varying yields and composition. Liquefaction could be generally defined as conversion process with the aim to produce liquid products (as primary product and/or with the highest yield).
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.
A mechanistic numerical model for coal liquefaction involving hydrogenolysis of strong bonds. Rationalization of interactive effects of solvent aromaticity and hydrogen pressure ... Hydrogen Transfer in the Formation and Destruction of Retrograde Products in Coal Conversion. The Journal of Physical Chemistry A 2006, 110 (21) ... (DCL) processes ...
Introduction. Direct coal liquefaction (DCL), invented by Friedrich Bergius in 1913 [1], encompasses the catalytic conversion of coal by hydrogen and high temperatures in presence of a solvent and was used to produce transportation fuels on a commercial scale in the first half of the past century especially in Germany and Great Britain [2], [3], [4].
Direct liquefaction (DCL) processes and technology for coal and biomass conversion C. B. Clifford Chunshan Song Chemistry 2011 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,. Expand 4
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.
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 ...
In the DCL technology, coal is converted to liquid by adding hydrogen at high pressure and temperature. Various DCL technologies have been developed in last hundred years such as Solvent Refined Coal (SRC)I and SRCII, Exxon Donor Solvent (EDS), HCoal and catalytic twostage liquefaction (CTSL) [7], [8], [9], [10].
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 ...
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 ...
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 ...
Coal liquefaction conversion to tetralinsoluble products was determined by changes in ash content in the partially reacted coal relative to that of the unreacted coal. ... A Novel Process of Biomass Gasification for HydrogenRich Gas with Solid Heat Carrier: Preliminary Experimental Results. ... (DCL) processes and technology for coal and ...
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 ...
The separate characterization of biomass, coal, and their respective chars aimed at identifying the effect of sodium during different stages of combustion. ... Direct coal liquefaction (DCL) is a main pathway for converting lowrank coals into energy via thermochemical transformation [713], and DCL technology refers to conversion of solid ...
The main examples of indirect liquefaction methods for converting biomass to liquid fuel employ synthesis gas as their feedstock. The majority of these processes were originally developed for the conversion of coal and natural gas to liquid products. Technically, however, they should work equally well using synthesis gas produced from oxygen gasification.
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 ...
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 ...
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).
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 to liquid technology includes direct coal liquefaction (DCL), indirect coal liquefaction (ICL), coal to methanol to gasoline (CTMTG), and coal tar hydrogenation (CTH) (Xie, 2021; Zhang et al ...
The conversion of coal to products soluble in tetrahydrofuran correlated strongly with the initial rate of gas uptake. The cyclohexane conversion of coal was also catalyzed. ... (DCL) processes and technology for coal and biomass conversion. 2011, 105154. ... A new process for catalytic liquefaction of coal using dispersed MoS2 catalyst ...
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...
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 ...
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 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 ...
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 ...
oaltoliquids (TL) technology enables conversion of abundant coal into valuable liquid fuels such as gasoline, diesel, and jet fuel. Methods include indirect conversion (coal to syngas, which can be converted to liquid hydrocarbons) or direct conversion (by various direct coal liquefaction methods).
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