基于临界沉积速度的湿法脱硫石灰石供浆系统优化  

Optimization of wet desulfurization limestone feeding systembased on critical deposition rate

作　　者：谷小兵 宁翔 孟磊 时浩 肖海平[2] GU Xiaobing;NING Xiang;MENG Lei;SHI Hao;XIAO Haiping(Datang Environment Industry Group Co.,Ltd.,Beijing 100097,China;School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]大唐环境产业集团股份有限公司,北京100097 [2]华北电力大学能源动力与机械工程学院,北京102206

出　　处：《洁净煤技术》2021年第6期225-230,共6页Clean Coal Technology

基　　金：国家重点研发计划资助项目(2018YFB0604301)。

摘　　要：湿法脱硫系统低负荷运行阶段石灰石供浆泵频繁启动,严重危害设备安全。采用最小不沉积速度试验研究石灰石浆液临界沉积速度,并据此进行供浆系统优化。结果表明,随着管径的增加,临界流速逐渐增大。当管径为40 mm时,临界流速为1.28 m/s,当管径增加到70 mm时,临界流速为1.76 m/s,临界流速增加了37.50%。随着含固率的降低,临界流速逐渐减小。当含固率为20%时,临界流速为1.42 m/s,当含固率为4%时,临界流速为1.06 m/s,临界流速降低了25.35%。随管径和含固率的变化,粗、细颗粒临界流速的变化趋势相同;管径对粗颗粒的临界流速影响较明显,含固率对粗、细颗粒临界流速的影响相差不大;在相同的管径和含固率下,粗颗粒的临界沉积速度大于细颗粒。依据石灰石浆液临界沉积速度确定最小流量,开发宽负荷补水供浆工艺,并且设计低负荷补水电动调节阀控制方案,实现了不同负荷下石灰石浆液实时按需调节。该切换控制逻辑已成功应用于现场,保证了石灰石浆液泵的正常运行,提高了设备的稳定性和安全性。During the low-load operation of the wet desulfurization system,the limestone slurry pump is frequently started,which seriously endangers the equipment safety.The minimum non-deposition velocity experiment was conducted to study the critical deposition velocity of limestone slurry,and the slurry supply system was optimized accordingly.The results show that the critical flow velocity gradually increases with the pipe diameter increasing.The critical flow velocity increases from 1.28 m/s at a pipe diameter of 40 mm to 1.76 m/s at a pipe diameter of 70 mm which increases by 37.50%.The critical flow velocity gradually decreases with the decrease of solid content.The critical velocity decreases from 1.42 m/s at a solid content of 20%to 1.06 m/s at a solid content of 4%which decreases by 25.35%.With the change of pipe diameter and solid content,the trend of critical velocity of coarse and fine particles is consistent.The effect of pipe diameter on coarse particles is more obvious,and the effect of solid content on coarse and fine particles is similar.Under the same pipe diameter and solid content,the critical deposition velocity of coarse particles is higher than that of fine particles.The minimum flow is determined according to the critical deposition velocity of limestone slurry and thus wide-load water supply process is developed accordingly.And a low-load water-supply electric regulating valve control scheme is designed to achieve real-time regulation of limestone slurry under different loads.The switching control logic has been successfully applied to engineering to ensure the normal operation of the limestone slurry pump and improve the stability and safety of equipment.

关 键 词：湿法脱硫 石灰石浆液 沉积速度 补水供浆 按需调节 

分 类 号：X701.3[环境科学与工程—环境工程]