| Based on actualities of the sludge management in city's waste water treatment plant is lagging seriously, making the waste water treatment plant that is invested and ran chronically by country and government can't use resources effectively and transfer the economic benefits quickly. The main reason of it is the plentiful results use of the sludge is researching now so that the item can not be used in production generally. We can see from the transportation examples between the waste water treatment plant and the sludge management structures that the number is seldom in our country, but it has been using abroad. However it exist some defects, for example ,using 1% concentration to transfer sludge in engineering like water and don't consider the complex nature of sludge one by one for reducing the transportation resistance , using high-speed to transfer and don't consider the energy waste for the pipeline can not be plugged. In this paper, sludge's rheological properties are considered and it researched from having sand and not under the two circumstances of un-heterogeneity and heterogeneity. In addition, the typical sludge which the initial precipitation sludge and its anaerobic digestion sludge are researched through setting the relative sludge transportation models.Through the established models that transition velocity and friction loss under the un-heterogeneity circumstance and critical velocity and friction loss under the heterogeneity circumstance, and connect the measured dates'analysis of sludge in the waste water treatment plant, these conclusions can be led to:â‘ In the computing model of sludge pipeline transportation under the un-heterogeneity circumstance, the transition velocity of sludge increase gradually from laminar to turbulence. The research of the resistance characteristics about sludge pipeline transportation when make the sludge as bingham plastic body in non-Newtonian fluid, these conclusion from Thomas's methods can be led to: the smaller the pipe diameter became, the smaller the sludge's change margin of concentration change curve about the drag coefficient f in different pipe diameter, instead still. It is important that every curve have a lower point that the drag coefficient is smaller. And because the difference of pipe diameter that point's concentration is difference. Obviously, the influencing factor of pipe diameter is very important in actual transportation. In addition, the different kinds of sludge that friction loss change is also different. The results of using Hazen-Williams's methods can show the increasing trend only, so that it is not convenient to choose the best transportation concentration.â‘¡In the computing model of sludge pipeline transportation under the heterogeneity circumstance, the sludge with sand belong to two-phase flow. Following the increasing of concentration and pipe diameter, the sludge's critical velocity V c also increase quickly. Comparing with the initial precipitation sludge, its anaerobic digestion sludge's critical velocity increase is quickly obviously. From the calculation of the friction loss we can see: the more the increasing of concentration in certain pipe diameter, the more the friction loss became quickly. When pipe diameter is different, the sludge change following the concentration increasing, pipe diameter decreases and the friction loss is opposite. Comparing with the initial precipitation sludge, its anaerobic digestion sludge's loss gradient of friction is decrease.â‘¢According to the two computing models of sludge pipeline transportation in this paper, we can use this way from the part favorable data to choose the best transportation parameters that can overcome the use of low velocity and the energy waste of the pump. It can note that use science way can improve solution of the sludge problems by optimization to determine the parameters. This paper laid a good research basis for our country use the technology of sludge pipeline transportation generally in future.
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