Research on the Monitoring Methods of VOCs Leak of Open Circulating Water System in Refineries

Open circulating water heat exchangers are widely used in refineries. According to the current emission standards, whether a circulating water system is leaking is determined by total organic carbon (TOC) concentration at the inlets and outlets of circulating water heat exchangers. However, this method is rough with low compatibility, making it hard to judge the actual leak of a circulating water heat exchanger. Taking a typical refinery with a yearly output of five million tons of oil as an example, we established a ledger of an open circulating water system and optimized the method to judge whether the system is leaking in this paper. The results show that there are 63% of the circulating water heat exchangers can be decided by monitoring the quality of circulating water. Among all, the leak of only 18.81% of the circulating water heat exchangers can be decided by monitoring the amount of TOC.