燃煤电站SCR烟气脱硝系统运行典型故障诊断

燃煤电站SCR烟气脱硝系统运行中典型故障包括脱硝还原剂供应不足、喷氨自动调节品质差、喷氨均匀性差等。为解决此类问题，以某电站SCR烟气脱硝系统为例，介绍了相应整改措施。其主要包括：（1）提高液氨加热蒸汽品质，清理氨系统杂质；（2）优化喷氨自动控制逻辑；（3）热态喷氨优化调整。试验结果表明，整改及优化后该厂脱硝系统故障基本得到消除，还原剂供应量随机组负荷变化而变化，喷氨系统自动控制可正常投运，SCR脱硝反应器出口NOx及逃逸氨浓度达到设计要求且运行平稳，脱硝系统运行的安全性和经济性均得到提高。

Diagnosis of Typical Operation Faults of SCR Flue Gas Denitrification System in Coal-Fired Power Plants

The typical operation faults of SCR denitrification system include insufficient agent supply, uniformity of ammonia injection and poor quality of its automatic control in coal-fired power plants. To solve these problems, taking a SCR flue gas denitrification system in a power plant for instance, the following solutions are presented: (1) improving the quality of steam used for heating up the liquid ammonia and cleaning up the impurities in the ammonia system; (2) optimizing the automatic control logic for ammonia injection; (3) optimizing the hot ammonia injection adjustment. The test results show that all these faults are eliminated after correction and optimization in this power plant. Now the quantity of agent supply changes with the unit loads, the automatic control system for ammonia injection operates normally, and the concentrations of NOx and ammonia-slip at the reactor outlet reach the designed requirements and keep stable in the operation. The security and economy of the denitrification system has been improved.