草酸盐和碳酸氢盐抑制聚乙烯粉尘爆炸特性

为研究草酸盐和碳酸氢盐抑制聚乙烯粉尘爆炸特性，选取NaHCO₃、KHCO₃、Na₂C₂O₄和K₂C₂O₄四种粉体，从火焰结构和火焰传播速度两方面分析其对聚乙烯粉尘爆炸的抑制性能，并结合抑爆粉体的理化性质分析抑爆机理。结果表明，四种抑爆粉体均可抑制聚乙烯粉尘爆炸火焰传播，且抑制效果随抑爆粉体浓度增加而增强。相同条件下，抑爆性能KHCO₃>NaHCO₃>K₂C₂O₄>Na₂C₂O₄，即钾盐粉体抑爆性能优于具有相同酸根离子的钠盐，碳酸氢盐粉体抑爆性能优于具有相同金属离子的草酸盐。另外，结合抑爆粉体热解特性测试及爆炸产物分析，探究了四种抑爆粉体的抑爆机理及离子构成带来的抑爆性能差异性原因。

Inhibition of polyethylene dust explosion by oxalate and bicarbonate

In order to study the suppression characteristics and mechanism of oxalate and bicarbonate on the explosion flame of polyethylene dust, two kinds of bicarbonate powders ( NaHCO₃, KHCO₃ ) and two kinds of oxalate powders ( Na₂C₂O₄, K₂C₂O₄ ) were selected. The inhibition performance of oxalate and bicarbonate on flame propagation of polyethylene dust explosion was analyzed from two aspects of flame structure and flame propagation velocity. Combined with the physical and chemical properties of four kinds of explosion suppression powders, the mechanism of inhibiting polyethylene dust explosion was analyzed. The results show that all four kinds of explosion suppression powder can inhibit the flame propagation of polyethylene dust explosion, and the inhibition effect increases with the increase of the concentration of explosion suppression powder. Under the same explosion inhibitor concentration, KHCO₃ had the best explosion suppression performance, followed by NaHCO₃, and then K₂C₂O₄ and Na₂C₂O₄. That is, the explosion suppression performance of potassium salt powder was better than that of sodium salt with the same acid radical ion, and the explosion suppression performance of bicarbonate powder was better than that of oxalate with the same metal ion. The four kinds of explosion suppression powders all have physical and chemical explosion suppression properties. In terms of physics, bicarbonate powder mainly has the functions of thermal desorption, dilution of oxygen and thermal shielding, while oxalate only has the functions of dilution of oxygen and thermal shielding. In terms of chemical, four kinds of explosion suppression powders can be pyrolyzed to produce active free radicals Na· and K·, and react with the high active radicals H· and OH· produced by polyethylene dust explosion to form Na·⇔NaOH and K·⇔KOH cyclic reaction, and then play an explosion suppression role by interrupting the chain reaction.