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According to reports from Sinochem News, reporters learned last week from China Coal Ordos Energy & Chemical Co., Ltd. that its Tuk branch has managed to keep its coal ash slag (BGL) gasification furnaces operating at high loads continuously through measures such as adjustments to the slag discharge process, optimization of operations, and upgrades to related components. In particular, Furnace No. 4 has been operating steadily for 364 days in a row, breaking the previous record set last year by Furnace No. 2, which had operated at high load for 291 days – the longest duration achieved by any company of its kind in China. It is reported that the gasification center at the Tuk branch facility has 13 BGL gasifiers, which supply syngas as a raw material for ammonia synthesis, urea, and methanol production units. This new type of clean coal gasification technology features high gasification temperature, large gas production per furnace, high coal conversion efficiency, as well as energy and water savings. The biggest difference from other furnace types is that the solid slag discharge technology has been replaced by liquid slag discharge, resulting in an extremely low amount of carbon residue in the slag. Cao Wenxu, manager of the company’s gasification center, told reporters that the original slag discharge system of the gasification furnace was subject to frequent erosion at high temperatures of 1300°C in a solid-liquid mixture, which led to wear and leakage; this became the main bottleneck restricting the long-term operation of the gasification furnace. The gasification center continuously works on process optimization by adjusting parameters such as the flow rate and circulation volume of the cooling water in the slag discharge system, thereby enhancing the heat exchange effect. This allows a slag layer to form on the inner surface of the components during operation; the washing process only wears away this slag layer without damaging the actual components, thus achieving the goal of using slag to counteract slag and extending the operational cycle. Since the commissioning of Gasifier No. 4 in September 2024, it has remained in continuous high-load operation as of September 23 this year, with an operational period of 364 days. Following proactive shutdown for maintenance, on November 3, the No. 4 gasifier resumed operation, embarking on a new journey. It is reported that in recent years, the company has carried out various technical upgrades to enable the long-term operation of the BGL gasifier. For example, cone valves have been replaced with shear valves to extend their service life and reduce maintenance time; ball valves on the main gas pipeline have been replaced to ensure reliable isolation between the rough coal gas pipeline of each gasifier and the main gas pipeline. At the same time, they strictly control the composition of raw coal, optimize process parameters, adjust the steam-to-oxygen ratio and load in accordance with different furnace conditions, strengthen equipment monitoring, and pay close attention to handling abnormal operating conditions. Currently, the average operating cycle per BGL gasifier has increased from 220 days to 284 days, with 6 of them having an operating cycle of over 300 days.