Study On Physical Interference Grind Aiding Technique And Its Electromagnetic Pulse Apparatus

Cement is the most principal building material in the world. In China, its output has reached 700 million tons per year. Cement production process consumes large amount of energy and natural resources. At present, a ton of cement expends comprehensively about lOOkWh of electricity about 60% of which is used in grinding section, Cement grinding process consumes high energy on low efficiency, only 0.6 to 1.0 percent of which is being used in increasing surface. Owing to the universal existence of buffer bedding formatted by cement powder adherence, energy consumption is on a high level continuously. It is no doubt that the newly cement regulation put into effect will promote cement quality, on the contrary it forces the cement fineness down and surface area up. If no relevant technological innovation adapt, the consequences would be that mill's condition take a turn for the worse leading to the increasing on grinding electricity cost. Supposing that electricity cost of cement grinding be cut down for 5%, the consequence is that 2.1 billion kWh of electricity, equivalent to 1 billion yuan, could be saved. Further more, a great quantity of dust, SO2, CO2 from power plant to environment will be reduced, so as to lessen load of environment. Therefore, saving the electricity of cement grinding is of momentous significance.By way of better the grinding technique and the mill construction could cut down grinding electricity cost, enhance the quality and quantity of mill system, but the phenomenon of excessive grinding should not be eliminated. Aiming at the phenomenon of excessive grinding formatted from physical action of electrostatic force, Van de wall's force and surface stretching force among the ground stuff in cement grinding process, the dissertation put forward a conception of physical grind-aiding and interference technique. Based on the idea that the physical field matching with anti-energy should bring the action of interfering with the factors worsening working condition so as to break pernicious balance due to excessive grinding, a new kind of dynamic balance benefiting to up-grade grinding efficiency could be set up. The initial research on physical grind-aiding technology went through the fundamental theory of electromagnetism by which the phenomenon of powder particle adherence and gathering together in grinding process could be studied, so the mechanism of interfering buffer bedding should be founded.Up to now, no study on the cement powder electrification and its harmfulness is pursued. First of all, the cement powder electrification mechanism was deduced from the theory of solid-surface-contacting-electrification. Next, electrification regulation of cement powder was verified by using the series of experimental system specially built for the electrostatic charge of cement powder, performance of its leakage, electrostatic voltage. The results show that cement powder particle adherence to inner wall of mill's thick and grinding bodies was reasoned from increasing of electrostatic charge of cement powder in grinding process. Therefore, the buffer bedding brought about from this led to decreasing on grinding efficiency. Temperature, cement risistivity, moisture content all are the effect factors on electrostatic charge of cement powder. The grinding-aids may obviously lower the cement risistivity, quicken leakage of cement electrostatic. As a result, electrostatic charge of cement powder reduced, and also grinding efficiency enhanced.The dissertation applied the principles of electrostatic induction for the theory explanatory of cement adherence layer, which proves attraction of the inductive electrostatic charge layer on the cement is one of the main reasons of cement adherence. The formation mechanism on the phenomenon of excessive grinding could formed and therefrom the cement adherence model of the inductive electrostatic double layer was built. By theory of electrostatic induction and analyzing the existing electrostatic-eliminated apparatus of powder, the direct additional electric field coul...