关于改进型CO_2汽提法尿素装置尿素合成塔的腐蚀与控制

尿素合成塔是改进型CO2汽提法尿素装置的4大重要高压设备之一。介绍了34万t/a尿素合成塔的基本结构;阐述了尿素合成塔的腐蚀机理;从温度、氨碳比、水碳比、甲铵液浓度、氧含量等方面等论述了尿素合成塔产生腐蚀的影响因素;提出了正常运行、开车、停车、封塔停车以及低负荷运行期间减缓尿素合成塔腐蚀的控制方法。

Corrosion and Control for Urea Reactor in Urea Plant by Modified CO2 Stripping Method

Urea reactor was one of the four important high pressure equipment in the urea plant of modified CO2 stripping method. Author has introduced the basic structure of urea reactor with a capacity of 340 000 t/a; has described the corrosion mechanism of urea reactor; has also discussed the influencing factors caused by corrosion of urea reactor from aspects of temperature, ammonia/carbon ratio water/carbon ratio, carbamate solution concentration, oxygen content etc. ; has presented the control method to decrease and slow corrosion of urea reactor during normal operation,, start-up, shutdown, reactor sealing shutdown and low load operation.