Gas jet limit liquid absorption method

Abstract

The invention discloses a gas jet limit liquid absorption method, and relates to the technical field of addition and application of liquid materials. The critical geometry occlusion phenomenon that occurs when the high-speed airflow flows through the jet is designed as a liquid absorption working point to achieve accurate quantitative addition of the absorbed liquid. The gas jet limit liquid absorption method is very suitable for workplaces with sufficient wind pressure and insufficient water pressure, and has the characteristics of strong applicability, high reliability, convenient operationand intrinsic safety. Based on the method, a resistance foam fire-extinguishing system for underground goaf area is proposed to break through the technical bottleneck restricting the stable addition of foaming agent, to greatly simplify the operation of the addition process, and to improve the applicability of the core equipment of the resistance foam fire-extinguishing. Meanwhile the addition method can also be used for the precise proportioning of ground fire gas foam fire extinguishing foaming agent, the micro control addition of foam dusting foaming agent, the addition of reagents and pigments in petrochemical places and the like, and has broad application and prospect.

Description

technical field [0001] The invention relates to a gas jet limit liquid absorption method, which relates to the technical field of liquid material addition and application, in particular to the field of foam agent addition in the preparation of fire-fighting foams in underground goafs of coal mines. Background technique [0002] Coal spontaneous combustion is the main disaster in the coal mining process. With the vigorous promotion of fully mechanized caving technology, the goaf has a large caving height, a large amount of residual coal is left, and air leakage is serious, and the coal spontaneously ignites frequently. Statistics show that 90% of mine fires in my country are caused by coal spontaneous combustion, of which nearly 60% occur in underground goafs. Coal spontaneous combustion in goafs not only burns a large amount of coal resources, but also easily induces gas explosions, causing greater casualties and property losses. . [0003] Field practice has shown that high...

AI Technical Summary

Problems solved by technology

Statistics show that 90% of mine fires in my country are caused by coal spontaneous combustion, and nearly 60% of them occur in underground goafs. Coal spontaneous combustion in goafs not only burns a large amount of coal resources, but also easily induces gas explosions, causing greater casualties and property losses

[0003] Field practice has shown that high-resistance foam is an effective means to prevent coal spontaneous combustion fires in goafs, and the stable addition of foam agents is the prerequisite for ensuring the reliable preparation of fire-fighting foams. However, the precise control of foam agents is always difficult for this technology. The bottleneck of the breakthrough made it difficult to control the working conditions of the fire extinguishing foam preparation process, the system was unstable, the operation was cumbersome, and the applicability was limited, which seriously restricted the large-scale application of this technology

[0004] At present, jet suction is the most commonly used way of adding liquid, but when using the traditional method of suction, jet suction is significantly affected by the pressure ratio, and small fluctuations in back pressure will cause changes in the negative pressure of suction, and the suction is not stable. It is difficult to achieve stable and accurate addition. At the same time, the loss in the process of jet suction is large, and some losses exceed 70%. For foam fire extinguishing in gobs in underground mines, if traditional water pressure is used to drive jet suction, excessive pressure loss will cause liquid suction. The outlet pressure of the device is insufficient, resulting in low back pressure, insufficient subsequent driving pressure, unstable foam, obvious pulse phenomenon, and weak foam with insufficient momentum

Images