Experimental Study Of Wettability Of Coal And New Wetting Agent

In this paper, the study on the wettability of coal and new wetting agent is researched comprehensively and systematically by the method of heoretical research, experimental analysis and analog application. The mechanism of jet atomization, spray dustfall and surfactants wetting the coal dust is elaborated, and the dust movement around droplet is discribed. It's pointed out that when surfactant is added into water, the adsorption layer is formed in the surface of droplet, the surface tension of droplet is reduced, the dustfall efficiency of droplet is enhanced. At the same time, as the redution of surface tension, the resistance of collision between droplet and dust is reduced also, and the wetting effeciency between droplet and dust is increased.The typical coal simples of Shandong province are collected. The moisture and ash content of each coal simple are measured through a lot of experiments. The wettability of each coal simple is test by DSA100 contact angle optical instrument, and the difficulty of each coal simple wet by water is determined. The impact of moisture, ash content and the degree of coalification on the wettability of coal simple is analyzed, and the typical coal simples of Shandong province are divided into three categories according the wettability of coal simple. At last, it's determined that the wettability of coal in Shandong province is poor, and surfactant is need in spray dustfall. Then the requirements of wetting agent for each categories coal simple are proposed.The research program of new wetting agent, to choose suitable surfactant, synergist and absorbent agent, then to detemine the formula and dosage of new wetting agent, is elaborated. In the experiments, the synergism of wettability from surfactant complex and the inorganic salt counterion is measured. The inner mechanism of the whole experiment process is anylized, and it's shown that the wettability of anionic surfactant solution may be enhanced through the addtion of little nonionic, amphoteric and cationic surfactant, and the addtion of inorganic salt counterion can greatly improved the wettability of anionic surfactant solution. At last,4 kind of new wetting agent for different kind of coal simples is determined, and the security and economic benefits of new wetting agent are recognized through the test of physiological toxicity and economy.The simulation application of new wetting agent is carried out in the simulation model for spray dustfall. The dustfall rate of 4 kind of new wetting agents for different coal simple is measured, and the use scope of 4 kind of wetting agents is got. It's shown that the dustfall rate of each kind of wetting agent reaches 90% in each use scope. According the economy anylisis of wetting agent, it's determined that the cost of spra dustfall by new wetting agent is less than 0.3% of coal output, and the growth of tons of coal cost is less thanï¿¥2 yuan. It's sure that the economic benefits of new wetting agent is conspicuous...