Risk Assessment Of Dust Explosion In Wood Floor Processing Workshop Based On SEM-BN

With the rapid development of decoration industry in China,the demand of wood floor is high.But the inflammable and explosive dust produced in the process of wood floor is easy to cause the safety problem of dust explosion.There are a certain number of processing equipment and various ancillary facilities in the wood floor processing workshop In the production process,there are many complex hazardous factors with uncertainty,which makes the identification,probability prediction and risk quantification of dust explosion risk factors in wood floor processing workshop challenging,and increases the uncertainty of assessment results.In view of the above problems,the risk assessment of dust explosion in wood floor processing workshop based on SEM-BN is carried out.The main contents of the study are:(1)The dust particle size range of wood floor processing workshop was measured to determine the explosion risk.Through the analysis of the special technological process and the particle size measurement experiment,the explosion risk in the process such as cutting plate and dedusting is analyzed.The particle size analysis of 10 groups of dust sampled in the workshop shows that the particle size of dust is less than 200 meters,and dust explosion accident will happen.(2)Structural Equation Modeling(SEM)is used to define the risk index system of dust explosion in wood flooring workshop and to study the complex relationship among the risk indexes.Based on the "five high" risk theory,63 dust explosion risk assessment indexes are initially selected.A questionnaire survey on dust explosion of wood floor processing workers is carried out..The Amos risk variable analysis model is established.Through model modification,the analysis model with reasonable path relationship and variable setting is obtained,that is,48 dust explosion evaluation indexes of wood floor processing workshop are obtained.(3)Bayesian network(BN)evaluation model is established to realize scientific prediction and risk reasoning of risk factors and risk target probability.Based on the dust explosion condition and accident cause theory,the BN model is established and the probability of each node is deduced.For example,the risk probability of seven nodes is greater than 30%,and the risk probability of eight nodes between 20% and30%.The reverse reasoning is used to diagnose the cause of the accident,and the causeprobability of each node is obtained.The sensitivity of 7 red nodes and 11 light red nodes is obtained by sensitivity analysis.The maximum Causal Chain analysis identifies 8 maximum causal chains.The scientific probability prediction of Bayes model is transformed into weight,and the fuzzy comprehensive evaluation method is used to avoid the introduction of subjective uncertainty.Finally,the risk level of dust explosion in the workshop is calculated as "safety" through risk quantification,which Provides basis for dust explosion risk grading control of wood floor processing workshop.