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The energy-saving optimization project for the moving-bed pure-oxygen continuous gasification process at Hebi Baofa Energy Technology has been fully connected and put into trial operation. Author/Source: Coal Chemical Engineering Journal; Date: May 24, 2022; Clicks: 16. In response to the policies regarding work safety as well as energy conservation and environmental protection set by ** and Henan Province, Hebi Baofa’s moving-bed pure-oxygen continuous gasification project transformed the fixed-bed intermittent gasification process into a moving-bed continuous pure-oxygen gasification process. A air separation unit was also constructed to supply oxygen, nitrogen, and instrument air to all the facilities in the plant. Additionally, some adjustments were made to processes such as desulfurization, shift reaction, decarburization, and further desulfurization in order to adapt to changes in the composition of the gas feedstock. The official production of methanol in this methanol synthesis unit marks the completion of the entire process for the year-long energy-saving optimization project involving continuous gasification using moving bed pure oxygen, with the facility now being put into operation. Upon completion of the project renovation, approximately 50,000 tons of standard coal can be saved each year, with carbon dioxide emissions reduced by over 100,000 tons. The coal utilization rate will reach 95%, thereby significantly improving the efficiency of comprehensive resource utilization and aligning with the policies aimed at achieving carbon peak and carbon neutrality. Project Name: Transformation Project of Moving Bed Pure Oxygen Continuous Gasification Technology. Project nature: Technical renovation. Product plan: 300,000 t/a dimethyl ether, 3,000 t/a sulfur, 8,580 t/a LNG. Investment scale: 200 million yuan. Production process: Raw coal, steam, oxygen → Purification (desulfurization, decarburization, further desulfurization) → Compression → Methanol synthesis → Dimethyl ether. Contents of the main project renovation: Gasification unit: A total of 22 gas generation furnaces were renovated (12 Φ3,200 mm gas generation furnaces and 10 Φ3,000 mm gas generation furnaces were all converted into continuous low-pressure pure oxygen gas generation furnaces). Air separation: A new air separation unit will be installed to supply oxygen as a raw material for the gasification unit; its oxygen production capacity is 30,000 m3/h. The process involves five main steps: air compression, air purification, air separation, storage of liquid products, and vaporization. Desulfurization: One additional desulfurization tower is added upstream of each of the two existing desulfurization towers for preliminary desulfurization, and the existing desulfurization towers are modified. After the modification, the total gas processing capacity is approximately 165,000 m3/h; the pressure remains consistent with that of the original system. The CO content is around 36%, and neither the gas volume nor the CO content changes significantly. The existing process flow, equipment, and catalysts are still utilized. The outlet CO level is controlled by adjusting the steam addition amount. Decarbonization: After the modification, the total gas volume increased by about 15%, while the CO2 concentration increased by up to about 27%. The first modification plan involves increasing the gas flow rate from 67,000 m3/h to 78,000 m3/h. The vacuuming time is extended and the vacuuming capacity is improved by increasing the number of vacuuming cycles; the process is modified to use three-tower adsorption, five-tower or six-tower vacuuming, with 8 or 7 pressure equalization steps, and 3 additional adsorption towers, 2 sets of vacuum pumps, as well as corresponding supporting equipment are added. The second modification plan involves increasing the gas flow rate from 79,000 m3/h to 89,000 m3/h; the vacuuming time is extended by increasing the number of vacuuming cycles, thereby improving the vacuuming capacity. The process is modified to use three adsorption towers, along with five or six vacuuming towers, and 8 or 7 pressure equalization steps. Additionally, 3 more adsorption towers, 2 sets of vacuum pumps, and related supporting equipment are added. Precision desulfurization: The gas volume and composition during precision desulfurization remain essentially the same as before the modification, and the existing equipment is utilized for this process.