Operating for 1.5 years, part of filtering bags for bag dedusters in a coal-fired power plant had severely decreased intensity and were generally broken. These disabled bags were mainly at the middle and tail of dedusters. By analysis, the reason of the ineffectual filtering bags is oxidation corrosion and more flue gas passing through, owing to the nonuniform distribution of gas. As an improvement measure, such methods are needed as operation optimization, installing de-nitrification system and adding gas uniform plate in dedusters.

The electrostatic-bag integrated precipitator is applied in some coal-fired power plants in recent years. In accordance with the investigation and analysis on 33 electrostatic-bag integrated precipitator,most of bags are broken up or replaced in more than two years. The reason shows that the contents of NO2 and SO3 of flue gas generated in electric precipitator increase and the strengthening degree of bags decreases, So that the filter bags in low reach are destroyed. We should be careful in application in order to avoid the unnecessary loss.1 Current Situation and Problem Analysis on Electrostatic-bag Integrated Precipitator

People pay more and more attention on the fine particle pollution in the air with the improvement of environmental awareness. Coal-fired power plant is an important source of the fine particle emissions. The principles of three dedusting methods applied in coal-fired power plants were explained, which were electrostatic precipitator, bag deduster and composite electrostatic-bag precipitator. In addition, PM2.5 removal efficiency of three dedusting methods was analyzed and discussed based on the test results. The experiment, with the AFC-131test rig, was carried out on dedusting performance of typical filters, to study the effect of pressure drop of filters on the emission characteristics of PPS filter material of different processing technology and posttreatment.

This paper analyzes the problem of furnace slag on opposite firing boiler using swirling combustion. Through the cold test methods, the airflow structure of the burner is explored, the formation mechanism of furnace slag is explicated, therefore the solution is drawn up, the slag problem of boiler is eliminated, the safety of unit operation is improved.

For the retrofit of precipitation and flue gas desulfurization (FGD) system, stalling issue of the boiler axial-flow induced draft fan (IDF) was analyzed. By testing the running characteristic parameter of IDF at the scene, and combining with its characteristic: curve, it was discovered that the actual working point of IDF nears its theory stall line, and stalling issue would appear during running. In order to make the actual working point of IDF keeping away from its theory stall line and avoid the stalling issue of IDF, KSE ( the steady implement of function ) equipment was installed at the entrance of the IDF' to changing the position of IDF theory stall line. The stalling issue of IDF was analyzed and probed, and the problem that the stall margin selection should be considered carefully in IDF retrofit and type selection was presented, which gives some useful suggestion for the similar retrofit in power plant.