Small Test Experimental Study In Deep Well Aeration Treatment Of Urban Sewage Sludge

Sludge produced in the city sewage treatment process was a complexheterogeneous body composed of colloid, organic debris, inorganic particles, bacteriaetc. Effective treatment of city sludge had great significance in terms of environmentalor economic terms. With the rate of sewage treatment and the process of urbanization inChina continued to improve, sludge treatment has become an increasingly urgent andserious issues facing China in the field of environmental protection.The core of the deep well aeration process was using underground vertical reactorto ultra-deepwater aerobic sludge digestion. The well was fulled of sludge, then pour airinto the well. due to the effect of the ascension of the gas and the difference between theinside and outside, sewage began to cycle; Cycle process as the hydrostatic pressuredecreases, the air dissolve in the water was gradually released, and gets release theremaining air with low oxygen content degassing pool. So deep well aeration had theoptimum hydraulics and the biological characteristics, high dissolved oxygenconcentration, oxidation.This paper studied the deep well aeration method (small) treatment of urbansewage sludge (moisture content96%). The sludge of Lanzhou saltworks sewage plantis adopted in the experiment, the organic matter content was forty to fifty percent in thewinter, and for more than10%in summer. This experiment first tested for operation onthe small kind of device, and then explored the factors affecting deep well aerationtreatment system, such as temperature, thermophilic bacteria. changes in the nature ofthe sludge was analyzed and the research, it is concluded the optimum operationparameters, for the next60meters pilot debugging and the experiment has laid a solid foundation.The main conclusions of this study were: middle aeration pipe pressure above the0.05MP, the liquid velocity of inside well was greater than1.0m/s; In the pilot reactordesign and processing, the position of the lowest aeration disc should be the bottom ofthe inside well; The position of start aeration ring should be cancelled. With air pressurechange, the fiow of spoil disposal has a peak, the value is0.025MP, flow rate about0.228m3/h; The temperature of autothermal reaction rose to2-5℃; Reactiontemperature under the condition of high temperature60℃near the best treatment effect;Sludge could produce high temperature thermophiles by itself, don’t need additionalsource,etc.