【Ten Years of Rapid Development in Chemical Processing Equipment】2012–2023: The First Set of High-Efficiency Radial Flow Turbines for Utilizing the Residual Pressure from CO2 Flue Gas Treatment Using Low-Temperature Methanol Wash

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Looking at the development of chemical technology over the past decade, we celebrate the prosperity and strength of modern China. This is just a starting point to encourage further discussion among everyone; with your participation, things will become even more interesting. [The Ten-Year Development of Chemical Equipment] – continuous updates and summaries are available; feel free to join the discussions at https://bbs.hcbbs.com/thread-3576046-1-1.html. Prevention first, life above all. ----------------------------------------- On October 29, 2023, the “High-Efficiency Radial Flow Turbine for Utilizing Remaining Pressure in CO₂ Exhaust Gas during Low-Temperature Methanol Washing” project, developed and put into industrial use by Jiangxi Xinlianxin Chemical Industry Co., Ltd. and Tianjin Kuaitouping Technology Development Co., Ltd., passed the technical achievement evaluation organized by the China Nitrogen Fertilizer Industry Association in Jiujiang, Jiangxi. After conducting the evaluation, the expert panel led by Gu Zongqin, president of the China Nitrogen Fertilizer Industry Association, unanimously agreed that this is the first such system in China; it features advanced technology, stable operation, significant economic and environmental benefits, and its overall technical level is at the leading stage in the country. The appraisal expert group also recommended further promoting and applying this technology. It is reported that the project was launched in April 2021, construction was completed in October 2022, and it underwent a successful trial run on October 27 at Jiangxi Xinlianxin before being put into use. Since its commissioning, this unit has operated continuously and stably, with the energy-saving capacity remaining at around 675 kW. Exceeding the 645kW energy-saving requirement specified in the contract, with the unit’s vibration level being less than 6um. When the expander operates near its rated conditions, the adiabatic efficiency obtained from experimental data is around 91.2%, which is close to the value calculated theoretically. As of October 27 this year, the project has been operating stably for 366 days, achieving a total energy savings of 5.61 million kW. Its main technical innovation is, firstly, the use of the residual pressure from CO2 flue gas treatment via low-temperature methanol washing for the first time in China. Secondly, while generating electricity, the low-temperature exhaust gas can provide cooling capacity for the facility. Third, the load of the turbine unit can be adjusted over a wide range, enabling high efficiency. 　This unit has been in continuous operation at Jiangxi Xinlianxin Company for one year. The operation results show that the actual annual energy savings amount to 5.42 million kWh, with an annual economic benefit of 4.05 million yuan (at an electricity price of 0.75 yuan/kWh). Additionally, 1,652 tons of standard coal are saved each year, and 4,321 tons of carbon dioxide are reduced. Furthermore, the exhaust gas with an inlet temperature of 28°C experiences a decrease in enthalpy due to expansion work, resulting in a temperature of around -19°C in the exit of the radial flow turbine, making it an excellent cold source. This project uses a cold energy heat exchanger to cool the circulating cooling water, thereby reducing the energy consumption of the cooling tower system in production. The cooling capacity provided by the unit is around 500 kW, and the annual cooling capacity of the project can reach 15,120 GJ.