Research On Explosion Characteristics Of Wood Dust And Risk Assessments Of Typical Production Environment

During the production of industry, dust explosion accidents always happen, which cause casualties, property damage, and environmental pollution. Flammable wood dusts are often accompanied in a form of fine particles in the wood processing industry. In order to prevent the probability of wood dust explosion accidents, mitigate the severity of consequences, ensure safety and stability of wood processing industry, it is imminent and greatly significant to study dust explosion risk assessment methods of wood processing places. In this paper, the risk assessment model is built according to unique technology or equipment in wood processing industry. And then the model is applied to a mahogany furniture factory as research case. The main research of this topic includes the following aspects:(1) Establishment of index system of dust explosion risk possibility in wood working places. According to the explosive environment is the basic premise of dust explosion and ignition source is a dynamic factor in promoting and development of dust explosion, the risk assessment index system is summarized in corresponding with investigation and analysis of the application status of wood working places. At the same time, potentially dangerous states of index layer are identified using the existing standards analysis and Delphi methods.(2) Experimental study on characteristic parameters of wood dust explosion. Considering the correlation between index layer and dust explosion, minimum ignition energy of dust cloud(MIE), minimum ignition temperature of dust cloud(MITC) and minimum ignition temperature of dust layer(MITL) are experimentally researched through Hartman tube, Godbert-Greenwald stove and hot plate stove. The dust specimens derive from mahogany wood dust. The relationship curves between dust particle size and minimum ignition energy, and between dust concentrate and minimum ignition energy are obtained through changing these parameters, i.e., dust particle size and dust concentrate, which will give a technical reference to risk management and control of dust explosion in the following section.(3) Research of dust explosion risk assessment methods of wood processing industry. On the basis of particularity of dust explosion risk possibility indicator system in wood processing industry, the combination weighting method based on Delphi and entropy is used to set the weighting of each indicator. By the way, the difference of weight is minimized by Game Theory. In attention to mutually independence of “explosive environment”, “ignition source” and “safe remedies”, the risk probability assessment model of dust explosion is created based on three-dimensional risk cube. The types of potentially explosive consequences are analyzed by casualties, property damage and environmental impact. The possibility of risk and the severity of consequence are integrated by risk matrix. Finally, based on the modified ALARP criterion, different risk level of dust explosion is ranked, and the corresponding prevention and controlling strategies are given.(4) Risk assessment programming of dust explosion in wood processing industry and its application. Based on risk assessment model of dust explosion in wood processing industry, the risk assessment program is written in Microsoft C# language. In order to validate the availability and engineering application value of research results, the risk assessment model and program are applied to practice.