混合气爆炸极限的理论计算方法

Theoretical Calculation Methods for the Explosion Limit of a Mixed Gas,

现有的文献资料中记载,爆炸极限的理论计算方法有三种基本类型:①适用于一种可燃气爆炸极限的计算方法—经验公式法;②多种可燃气组成的混合气爆炸极限的计算方法—理查特里公式法;③可燃气与隋性气的混合气爆炸极限的计算方法。储油罐中气体,多是含有氧气、惰性气和多种可燃气的混合气。由于原油组分、馏分不尽相同,此类混合气的爆炸极限难以统一确定,即使有测定的爆炸极限,也只适用于某个油田、某种原油。为了掌握此类原油蒸气混合气的爆炸极限,结合石油储运的具体情况,根据爆炸极限表示的是可燃气在空气中体积百分含量的思路,总结出一种理论计算方法:先将混合气中的空气部分抽出,再将余下的混合气看作单位1,按此时混合气所属基本类型的计算公式进行计算,所得爆炸极限就是含有氧气、惰性气和多种可燃气的混合气爆炸极限。

In the literatures available, three basic methods are found for the theoretical calculation of explosion limit:①pexpirical fomula for calculating the explosion limit of a flammable gas; ②fomula for calculating the explosion limit of a mixture of multi-flammable gases; ③the method for calculating the explosion limit of the mixture of flammable gas and inert gas. The gas in oil storage tank is a mixture of oxygen,inert gas and several other flammable gasses. Due to the different compositions and fractions of crude oils,it is difficult to determine universally the explosion limit of this gas mixture, and the explosion limit determined can only be suitable for the specific oil in some oil field. A theoretical calculation method is concluded in this paper based on the actual applications: separating off the air from the gas mixture, considering the remaining mixture as one unit and calculating the explosion limit of the mixture of oxygen, intert gas and other flammable gases based on corresponding formula.