Development Of Coal Dust Suppressant And Its Industrial Application

With the rapid economic development in recent years in China,the demand for energy is also increased.However,the distribution of energy in China is extremely uneven.The lack of gas and oil and the abundance of coal are the main status for Chinese resources.Coal was the main energy for China for a long time.In the process of coal storage and transportation,a large amounts of fine coal dust would emit into the atmosphere,which caused serious dust pollution and affected the environment,transportation,peoples' daily life,and also caused the waste of resources.It is significant to develop the control of coal dust pollution.In this paper,an environmentfriendly compound dust suppression agent was developped for coal dust emission.Based on the investigation of dust suppressants in domestic and abroad,a comprehensive dust suppressants was developed made of agricultural waste straw,starch and alkali substances.Then industrial production was developed and dust suppression effect was investigated.Furthermore,an optimization dust suppressant was discussed through adding a modified starch.The basic performance tests such as viscosity,surface tension,water loss rate,wind and rain resistance of the modified dust suppression were investigated,the research results were as follows:.1)The effects of the different types of starch,the amount of starch,the amount of alkali,and temperature on dust suppressant properties were investigated.The results of single factor analysis showed that potato starch was the best and the preparation temperature was 60 ?.The best ratio of raw materials straw,starch and alkali was 10: 6: 0.9 by means of response surface method;2)The basic characterization test of the dust suppression agent showed that the viscosity of the prepared dust suppression agent was 180~240mPa·s,which had good adhesion with dust particles and was also easier to spray;the surface tension was 57.89mN/m and the contact angle was 37°,which proved that the dust suppressant was easier to adhesive with dust than water;3)The morphology of dust suppressant before and after spraying showed that a shell film was formed on the surface of dust particles.,The results of the experiment of the resistance to the wind and the rain showed that the shell film had a certain strength,which could resist the impact of wind and rainfall.The test of evaporation resistance showed that the dust suppressant has strong water retention and could moisturize dust for a long time;4)The industrial production of dust suppression agent showed that the performance of dust suppressant prepared under the condition of temperature of 60~80°C and straw particle size of 0.1~2cm did not change significantly,and there was no specific requirement for the aqueous solution concentration of starch and alkali,demonstrating the dust suppression agent.With the potential of industrial production and promotion value;5)The preparation temperature was descended from 60 ~ 80 ? to 20 ? or room temperature after the dust suppressant improved by modified starch.Moreover,the properties of the dust suppressants made of modified starch were not lower than those of the original formulation.In addition,because the modified starch was more soluble in water,which could enhance the viscosity of the system,decrease the use of modified starch and the production cost.Because the improved dust suppressant was the solid powder,which could solve the problem of transportation and conservation.