加氢裂化装置高压空冷器风机的改造

某石化公司150×10^4t／a加氢裂化装置高压空冷器风机风量小，叶片和翼型存在缺陷．传动方式效率低，导致高压分离器温度上升，气相循环氢体积增大，相应增大了循环氢压缩机负荷，造成汽轮机蒸汽耗量增加，循环氢纯度降低，产品质量变差。对高压空冷器4台风机实施了改造：采用新型HY系列玻璃钢叶片替换TB型铝风机叶片．采用啮合传动型的同步带传动替换摩擦传动型的多楔带传动。与改造前相比，改造后风机全压从170Pa提高到200Pa，风量从36×10^4m^3／h提高到46×10^4m^3／h，平均风速从3．391m／s提高到3．875m／s；反应流出物的温降提高了5℃；汽轮机3．5MPa蒸汽消耗量每小时可节约0．6t;加氢裂化装置运行平稳。加工量从149．44t／h提高到164．75t／h。

Revamping of Fans of High-pressure Air-cooled Heat Exchanger of Hydrocracker

The fans of the high-pressure air-cooled heat exchanger of a 150×10^4t/a hydrocracking unit in a petrochemical company suffered a series of problems such as excessively small air volume,defective blades and airfoil profile and low-efficiency driving mode.These problems led to a rise in the temperature of the high-pressure separator as well as the volume of the gaseous circulating hydrogen,increasing the load of the circulating hydrogen compressor and resulting in a rise in the steam consumption of the steam turbine ,a decline in the purity of the circulating hydrogen and a deterioration of the quality of product.To resolve these problems,technicians revamped these four fans of the high-pressure air-cooled heat exchanger.Specific measures ineluded：a new type of HY-series blades made of glass fiber reinforced plastics were used to replace the TB-type aluminum blades;meshing-drive timing belts were used to replace the original friction-drive serpentine belts.After the revamping,the total pressure of fans rose to 200Pa from 170Pa,the air volume increased to 46×10^4m^3/h from 36×10^4m^3/h and the average air speed went up to 3.875m/s from 3.391m/s.The temperature drop of the reaction effluent increased by 5℃ ;The steam consumption of the steam turbine at 3.5MPa dropped by around 0.6t per hour;the hydrocraeking unit has been operating steadily and its processing capacity rose to 164.75t/h from 149.44t/h.