The Project Study On The Appling Of Agricultual Wastes

As a large agricultural country, a great deal of straws and excrements of livestocks are engendered. Because we don't reasonably deal with and utilize them, they have a greatly bad effect on the ecological environments in the countryside. So this paper makes it as the research subject that how to reasonably and economically take advantage of straws and excrements as the reaources.Because the total amount of the straws and excrements can't be predicted directly, we make a mathematical model to predict it in an indirect way. Using the relationship between the grain mass and straws, and between the amount of poultuies and the excrements, according to the statistical data, we can predict the generation of the straws excrements. In the end of this part, we use the statistical data of TianJin, make anlysis and prediction as an illustration.After assorting and comparing the purposes of the straws and excrements, we analyze the economical efficiency of these purposes, and specialize the problem during appling process of theses purposes. In this part, we enumerate the techniques of producting feedstuff and biological fertilizer with the straws and excrements, and expain the ecact specialties and technical flows. At last, we anlyze the economical efficiency of using these techniques and make some planning for developing these techniques.According to the applied value of marsh gas and the different features in different areas, we explain the producting mode and flow about how to appling the marsh gas. At the end of paper, we use some economical indexes, like investment recovery period and internal rate of return, to evaluate the benefit and the uncertainty tor the techniques of appling marsh gas, in order to provide some advice for the marsh gas project.