【Ten Years of Rapid Development in Chemical Equipment】From 2013 to 2023, the operational life of the nozzles used in continuous coal-water slurry gasification processes exceeded 120 days

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At present, in the water-coal slurry gasification industry, the average service life of the nozzles used in 6.5MPa gasifiers is around 80 days, while the operational cycle of the gasifier systems itself is 140–240 days. As the operational cycle of gasifiers increases, higher requirements are placed on the service life of these nozzles. With the mission of addressing the actual problems faced by users on-site and developing internationally leading nozzles, Shaanxi Xinli has engaged in extensive discussions and collaborative efforts with its customers on numerous occasions. Leveraging years of experience in the chemical industry, the user’s experts provided many valuable suggestions. Based on the quality of the coal used, its grading, and various process parameters, our company conducted CPFD computational fluid dynamics simulations on the nozzles. We continuously worked to optimize the design of these nozzles as well as their components that are prone to wear, thereby extending their service life. Recently, the process nozzle for the gasification furnace, which was innovatively repaired by Shaanxi Xinli Nozzle R&D Co., Ltd., was used in Shaanxi Runzhong Clean Energy Chemical Co., Ltd. during a planned shutdown period; it operated continuously for 120 days. This represents another long operating period for this nozzle by this customer, following a previous 98-day operation of another type of nozzle, and it sets a new record for the longest continuous operation time of a process nozzle since the company began operations. The gasification unit of Shaanxi Runzhong Clean Energy Chemical Co., Ltd. is equipped with 3 units (2 in operation and 1 as backup), with a daily coal input of 1,500 tons (on a dry basis) per unit, and a gasification pressure of 6.5 MPa. The SXMH-03 nozzle, which was repaired using this innovative method, was used in the A# gasification furnace. During operation, the pressure difference across the nozzle remained stable and the atomization effect was good; the concentration of useful gases (CO+H2) reached 82%, meeting the requirements of the production process. The specific operating conditions were as follows: The SXMH-03 nozzle was put into use in the A# gasification furnace on August 6, 2023. The maximum operating load was 83 m3/h of coal slurry, with a pressure difference across the nozzle of 0.5 MPa. Due to issues with the supply of raw coal, the furnace operated at a rate of 75 m3/h of coal slurry for a short period of time; overall, the operating load remained between 78–80 m3/h of coal slurry. The furnace operated steadily until scheduled shutdown for maintenance on December 5, having run for a total of 120 days. At the time of shutdown, the pressure difference across the nozzle was 0.43 MPa, remaining fairly stable without any fluctuations. The operating cycle of these continuous-process nozzles has exceeded 120 days in each instance; this extended downtime marks a new milestone in terms of the service life of these nozzles at Shaanxi Runzhong Clean Energy Chemical Co., Ltd., with that life span now reaching 6.5 MPa – a level that is ahead of the industry standard for water-coal slurry gasification processes.