The coal-to-gas division of Xinjiang Qinghua Group has achieved phased success in its efforts

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The coal-to-gas division of Xinjiang Qinghua Group has achieved a phased victory in its efforts. Author/Source: Xinjiang Qinghua Group. Date: 2021-11-11. Clicks: 22. On the afternoon of November 5, the coal-to-gas division of Xinjiang Qinghua Group held a summary meeting at the gasification center to discuss ways of reducing the steam-to-oxygen ratio in the gasification process. The meeting announced that the campaign carried out by the gasification unit at the gasification center from August 25 to October 25, under the theme of \"Strict control of the oxygen-to-gas ratio, innovation for breakthroughs, improved quality and efficiency as a sign of commitment, and concerted efforts over 60 days,\" has achieved partial success. At the meeting, Zhang Sensen, assistant to the director of the gasification workshop at the Gasification Center, delivered a presentation on these achievements. He pointed out that through 60 days of relentless effort by all staff members, who continuously innovated and explored new methods for operating the gasifier, it was possible to significantly reduce the oxygen-to-gas ratio, thereby ensuring the stable operation of the project. Currently, the average steam-to-oxygen ratio in the gasifier has dropped to 7.08 Kg/Nm3, a reduction of 0.7 Kg/Nm3 on average. Based on the current oxygen load of 60,000 Nm3, it is possible to save 42 tons per hour of 5.0 medium-pressure steam, while also reducing the amount of wastewater generated by 42 tons per hour. Reducing the steam-to-oxygen ratio caused significant changes in the composition of the raw gas; the CO2 content decreased significantly, while the CH4 level increased by an average of 0.59%. CO increased by an average of 2.53%; the amount of raw gas fed into the main shift reactor increased, resulting in higher reaction heat and rising bed temperature, which led to a reduction in the consumption of medium-pressure steam for shift cooling by 10 t/h. The residual carbon content in the ash of the gasifier has dropped from around 10% to 5%. The economic benefits are significant. It is understood that since March 2021, due to insufficient supply of raw coal, the Qinghua coal-to-gas project in Xinjiang has been operating at reduced capacity. The Coal-to-Gas Division has made energy conservation, cost reduction, and improved efficiency the focus of its work for 2021. The gasification unit at the gasification center is a key project aimed at saving energy and reducing consumption by lowering the steam-oxygen ratio. Multiple specialized meetings were held with technical personnel and key operators from the control teams to analyze operational data, identify the reasons for high steam-oxygen ratios, and find solutions; through repeated discussions and research, the operating methods were continuously improved. Since August 23, Furnace A7# has begun to reduce the steam-oxygen ratio, lowering it from 7.6 kg/Nm3 to 6.75 kg/Nm3; ultimately, the average steam-oxygen ratio in the gasification furnace was reduced to around 7. This has made a significant contribution to the company’s efforts to save energy, reduce consumption, and improve efficiency.