Version 3.0 of coal-water slurry technology benefits the coal chemical industry

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Version 3.0 of coal slurry technology brings benefits to those in the coal chemical industry / Source: China Chemical Industry News, Date: 10-18-2016, Clicks: 18. Concentration as high as 70% with significant emission reduction effects. On October 14, reporters from China Chemical Industry News learned from the China Coal Research Institute that the pilot test of the third-generation coal slurry preparation technology developed by the institute’s Coal Slurry Engineering Technology Research Center had just been completed. The concentration of the coal slurry reached 70%, and the production of syngas increased significantly. This solution addresses the long-held goal of greatly increasing the concentration of coal slurry in the coal chemical industry, bringing good news to an industry that is currently going through a difficult period. “Coal gasification is the cornerstone of coal chemical industry, and a water-coal slurry gasifier is essentially a heat-balanced furnace. The coal slurry concentration is closely related to the effective gas content and the efficiency of coal gasification; for every 1 percentage point increase in concentration, the effective gas content increases by 0.7~0.8 percentage points. ”Li Falin, director of the Water-Coal Slurry Engineering Technology Research Center at the Coal Science Academy, said, “If too much water is present in the coal slurry, it will inevitably consume heat within the system.” To maintain a constant temperature inside the furnace, it is necessary to increase the oxygen supply, which results in more CO2 being produced. If 1 ton less water is added to the furnace, 450 standard cubic meters more of useful gas can be produced, 225 standard cubic meters of oxygen can be saved, and CO2 emissions can be reduced by 450 standard cubic meters. ” The particle-controlled slurry process, known as version 3.0 of the third-generation coal water slurry preparation technology, is the result of equipment and process upgrades developed by the Coal Water Slurry Engineering Technology Research Center based on the two-generation slurry preparation technology of classification grinding. Experimental results show that for certain high-quality coal types (Yuheng and Xinjiang Heishan coal), the pulping concentration can reach 69%–71%, while for conventional gasification coal types, it is 66%–68%. When combined with multi-nozzle opposed gasification technology, the effective gas yield can reach 86%–88%, approaching that of coal powder gasification, thereby opening up new options for coal chemical enterprises in choosing gasification processes. 　 Li Faling said that the research team at the **Water-Coal Slurry Engineering Technology Research Center of the Coal Science Academy, based on theories of hierarchical stacking and fluidity, resolved the technical challenges related to stacking efficiency (concentration) and fluidity that have long plagued the slurry production industry, achieving a bimodal, discontinuous particle size distribution for water-coal slurry ； A flow meter was specifically developed to address the unsoundness of using viscosity as an indicator for the fluidity of coal slurry. Li Falin told reporters that existing coal chemical plants can also be upgraded by integrating the existing rod mill pulping system. Taking a 600,000 tons per year methanol production project as an example, with the coal feeding amount remaining unchanged, increasing the slurry concentration from 60% to 68% reduces the water addition rate by 23.33 tons per hour, allowing for an increase in the production of effective syngas by 10,500 standard cubic meters (while simultaneously reducing CO2 emissions by 10,500 standard cubic meters). This results in an increase in methanol production of 5.05 tons per hour, as well as savings of 5,249 standard cubic meters of oxygen per hour. At a selling price of 1,800 yuan per ton of methanol, this can generate an additional income of 72.72 million yuan per year. Taking into account the savings in oxygen and other resources as well, the annual economic benefit exceeds 100 million yuan, while the investment required for the transformation is only slightly over 30 million yuan. To date, the center has completed the development of the pulp-making process package for a methanol production capacity of 600,000 tons per year, and is preparing for an industrial demonstration.