Study On The Durability Evaluation Method Of The Structure Of The Electrostatic Precipitator

ESP has the characteristics of high efficiency and energy saving,and is widely used in flue gas purification of thermal power plants.Because its body structure is made up of steel components and its environment is a special corrosive environment,the structure of the ESP is easy to be corroded,and the durability problem is serious.In view of the structural characteristics of the ESP and the factors affecting the durability of steel,this paper,based on the analytic hierarchy process,combines entropy weight method and fuzzy mathematics theory,gives the membership function of the factors affecting the durability of the structure of the ESP,and establishes a durability evaluation method under the multi-layer fuzzy comprehensive evaluation.According to this method,the durability of an ESP made in Lanzhou electric power repair plant has been evaluated for 18 years,and the result is more consistent with reality.The main achievements of this paper are as follows:(1)Determine the influence factors of the durability of the steel members which consist of the structure of ESP: the corrosion environment,the appearance,the corrosion rate of the coating and the average corrosion depth.(2)According to the structural characteristics of the ESP,the durability of the structure of the ESP is divided into the durability of the ash bucket,the durability of the bearing structure and the durability of the wall enclosure.Furthermore,it is further subdivided into durability of steel members.Based on this,an analytic hierarchy process(AHP)model for durability of ESP is established.(3)The subjective weight of the factors affecting the durability of the structure of the ESP is given,and the subjective weight of four factors affecting the corrosion environment,the appearance,the corrosion rate of the coating and the average corrosion depth is corrected by the entropy weight method.(4)Establish,the membership function of four influencing factors including corrosion environment,appearance,coating corrosion rate and average corrosion depth,and calculate the membership degree of the four influencing factors.(5)The fuzzy judgment matrix is constructed,and the membership degree of the influence factors on each layer is obtained according to the membership degree of the four influencing factors at the bottom of the durability level model.(6)According to the structure of ESP and the membership degree of each steel member,a calculation method of durability score is established.(7)According to the durability evaluation method of the ESP body structure establishedin this paper,the durability evaluation of an ESP in Lanzhou electric power plant is carried out,and the reasonable maintenance and reinforcement suggestions are put forward on the steel parts and the body structure according to the weighted score.