| 摘要 |
<p>Provided are a method which can coagulate the sludge of the water purification plant that is an environmental waste in a very environmentally friendly manner even without using a chemical solidification agent by coagulating sludge of a water purification using chitosan with high molecular weight, and a method for decomposing chitosan with high molecular weight into chitosan with low molecular weight which has affinity relative to the soil and facilitates multiplication of beneficial bacteria useful to plants by using a chitosan decomposition enzyme. A method for treating sludge of a water purification plant comprises the processes of preparing an aqueous chitosan solution with a concentration of 0.1 to 3% from chitosan having a molecular weight of 200,000 or higher, adding the aqueous chitosan solution to a suspension of the water purification plant to coagulate the sludge of the water purification plant, filtering and pressing the coagulated sludge of the water purification plant to produce chitosan-contained sludge having a water content of 15 to 20%, and mixing 0.01 to 1 wt.% of a chitosan enzyme with the chitosan-contained sludge based on the weight of the produced chitosan-contained sludge of the water purification plant, and fermenting the mixture to obtain chitosan sludge.</p> |
