Abstract: At present,local governments pay more and more attention to the treatment of wet plume. Coal fired power plants,iron and steel,coking and other industries have carried out wet plume treatment reform.However,there is a lack of systematic analysis on the factors affecting the desulfurization water balance,which leads to the difficulty of controlling the desulfurization water balance or the flue gas temperature exceeding the standard.Based on the historical online data,theoretical analysis and calculation,in this paper,the influencing factors of desulfurization water balance in coal-fired power plants were comprehensively summarized and quantitatively analyzed.For the first time,the influence of coal quality,environmental conditions,denitrification and other environmental protection facilities on the water balance of desulfurization was clarified.The results show that the total water and hydrogen content of coal are the most important factors,and the difference of flue gas temperature of several typical coals is more than 10 ℃ .The influence of environmental temperature and humidity is obvious. When the ambient temperature rises from 0 ℃ to 40 ℃( assuming the relative humidity is 60%),the difference of flue gas temperature is 4.6 ℃ .Air excess coefficient( or oxygen content) also has a great influence.When the oxygen content increases from4% to 8%,the difference of exhaust gas temperature is more than 2.5 ℃ .When SNCR and other processes are used,urea solution contains a lot of water,and the influence on flue gas temperature of desulfurization can reach 1 ℃ .The influence of flue gas temperature at desulfurization inlet on flue gas temperature is obvious,and the specific difference is related to flue gas temperature and coal quality.In addition,the unit load and other factors will also have a greater impact on the desulfurization water balance. In the scheme of zero discharge of wastewater,high salinity wastewater from cooling tower wastewater is often used for demister flushing,which determines that the desulfurization system must receive make-up water and ensure water balance. The influence of different wet plume treatment schemes on the water balance of desulfurization is also different. The flue gas condensation technology has no effect,while the slurry cooling technology has a great impact.Therefore,in the technical solution selection and parameter design of wet plume treatment,the above factors should be considered comprehensively.Selecting the appropriate technical solution and design parameters is of great significance to reduce the investment and operation cost and improve the reliable operation of the system.