Quantitative Structure-property Relationship (QSPR) Study On The Minimum Ignition Energy Of Combustible Gas Or Liquid Vapor

Minimum ignition energy is one characterization of the important parameters ofcombustible materials in electrostatic sparks or electric spark ignition risk, which islargely applied in the explosion prevention technology. Smaller minimum ignitionenergy indicates that the fuel is more sensitive to electric spark. Compared withcombustible industrial dusts, combustible gas or steam usually has higher ignitiontemperature and much lower minimum ignition energy. Minimum ignition energy canbe used not only in risk assessment for the production, storage and transportation offlammable substances, but also in the monitoring and controlling technology as theexplosion indicator parameter. The minimum ignition energy of flammable gas orcombustible liquid vapor is of great significance for understanding the medium forspark ignition sensitivity, taking effective measures to prevent the explosion or anyrisk.At present, researches on factors affecting minimum ignition energy ofcombustible gases (or flammable liquid vapor) and researches on the relationshipbetween the molecular structure and its minimum ignition energy are quite weak.There is a basic chemical law that molecular performance is determined by themolecular structure. In this thesis, experimental measurement and numericalsimulation are combined to characterize the relation between the minimum ignitionenergy and molecular structure of combustible gas and liquid vapor under different ininitial temperature. What`s more, other experiment on the relationship between theminimum ignition energy and different initial temperature. The technology ofpredicting the minimum ignition energy of is also developed.Based on the above ideas, this topic has carried on the following research andachieved the desired results:(1) Predicting the minimum ignition energy of combustible gases and liquid vapor at normal temperature and pressure. CODESSA software was applied to accumulatethe molecular structure descriptors of80combustible gases and liquid vapor. Fourstructure descriptors were selected by using the best multiple linear regression(B-MLR) and heuristic regression (HM), respectively, and the related QSPRcorrelation models were also established. For the prediction set, R2(coefficient ofdetermination) of the minimum ignition energy established by B-MLR and HMmethod was0.9802and0.9806, respectively, indicating the good imitative effect.(2) The minimum ignition energy test device is improved on the basis of nationalstandard test method for the first time. And the improved test device allows to test theminimum ignition energy of combustible gas or liquid vapor under differenttemperatures for the first time.(3) Studying the effect of initial temperature on the minimum ignition energy ofcombustible gases and liquid vapor. The minimum ignition energy of propane,isobutylene, isobutane and ethylene oxide in a temperature range20to80℃has beendetermined by using a minimum ignition energy test system and the effect of initialtemperature on the minimum ignition energy has been investigated as well.In a word, this study has great theoretical significance and practical value forpreventing major explosion accidents, which can technically support safe operationand determination of controlling conditions.