Coal Liquefaction

GSE's patented LIQUEX® direct coal liquefaction technology can be utilized to extract hydrocarbon liquid from mined coal. During extraction, the majority of any moisture present in the coal is also removed, thereby producing a final coal product with very low moisture.

The LIQUEX® process is conducted by mixing ground coal with GSE's proprietary solvent, GSX®. At this time, GSX® extracts and dissolves bituminous material as well as other organic matter from the coal. The resultant mixture undergoes solid-liquid separation to produce a liquid stream and particulate solids.

The liquid stream generally consists of GSX®, coal derived liquid (CDL) and water from the coal. Depending on the specific coal feedstock, a fraction of heavy metals and/or minerals (i.e., pollutants) may transfer to the liquid extract mixture. If necessary, any pollutants present can be treated with relative ease. GSX® is separated from the CDL via distillation for future use in the process. The particulate solids are comprised of material originally present in the mined coal less the CDL, the majority of moisture and any pollutants not removed during extraction.

GSE's LIQUEX® coal extraction process offers an economically and environmentally sustainable solution for coal liquefaction. The process results in two potentially higher value added products: (1) a coal derived liquid comprised mainly of hydrocarbons; and (2) a low moisture solid coal. The value proposition is two-fold in that both low-grade coal and high-grade coal can benefit from the technology. Low-grade coal generally yields less CDL, but produces a solid fuel with significantly higher heating value (i.e., Btu/lb) than the mined coal as a result of removing a relatively large quantity of moisture. High-grade coal, which is typically low in moisture, generally yields more CDL and results in a heating value equivalent to that of the mined coal.

The liquid coal is representative of a heavy synthetic crude oil that can be marketed as one or more of the following products:

  1. Heavy fuel oil blend, e.g., No. 6 fuel oil;
  2. Fuel for electric power generation via direct combustion by replacing coal, e.g., in remote areas where it is difficult to ship and/or support infrastructure necessary to burn coal;
  3. Refiner feedstock to produce transportation fuels;
  4. Refiner feedstock to produce specialty chemicals; and
  5. Feedstock to secondary process, depending on coal characteristics, to produce anode-grade binder pitch.

Depending on the quantity of moisture removed from coal during the LIQUEX® process, the solid product can be marketed as a low-moisture coal with a heating value that is either equivalent or greater than that of the unprocessed coal. That is, the heating value is upgraded as moisture is removed from mined coal, which can add significant value to the coal. Any removal of specific pollutants could also add value to the final coal product.

For coal producers, the potential benefits of GSE’s technology include the following:

  1. Expanding the marketability of coal, including lower grade coal, by yielding two higher value-added products;
  2. Liquefying coal directly without the aid of a catalyst, promoter and/or surfactant;
  3. Removing the risk of operating coal-liquefaction plants under extremely high temperature and pressure;
  4. Enhancing the environmental sustainability of the liquefaction process;
  5. Lowering capital and operating costs compared to alternative coal liquefaction technologies;
  6. Enabling producers to establish an economically compelling process in light of the recyclability of the reagent as well as the relative simplicity of the technology; and
  7. Minimizing the required utilities and carbon footprint from the process.

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