| The sewage sludge,the properties are highly moisture content and easily corruption,is by-product from the municipal sewage treatment plant.There are heavy mental and harmful organics in sewage sludge.Incineration can be acted as a measure to disposal the sewage sludge that product much energy due to content highly organics.With the continuous of China's urbanization,the discharge of waste water in urban increase every years,so the sewage sludge discharge from the municipal sewage sludge is also increase.A consummate urban facility symbol is whether the city able to completely treat the sewage sludge.The object of study is sewage sludge from main urban area in Chongqing in this project.The thermogravimetric analyzer is used for researching the different influencing factors under using different parameters in sewage sludge combustion.The sewage sludge combustion procession is divided into four steps.They are the moisture volatilization step,volatile organic compounds combustion step,in-volatile organic compounds combustion,fixed carbon combustion respectively.It is continuously increasing that the moisture content in sewage sludge volatilization temperature.Both volatile organic compounds combustion step's and in-volatile organic compounds combustion step's temperature are increasing under the moisture content increasing.The fix carbon combustion step is masked due to the moisture content in sewage sludge.Therefore the fix carbon combustion temperature can not carry out.The volatile temperature of moisture content in sewage sludge and sewage sludge ignition temperature are increases with the heating rate increase.Also the combustion loss rate is increases in steps of sewage sludge combustion.This paper obtained the best mechanism function of the moisture volatilization step,volatile organic compounds combustion step,in-volatile organic compounds combustion step,fixed carbon combustion step through Gorbatchev method.Fitting curve are used for carrying out activity energy and frequency factors in sewage sludge combustion steps by comparing the correlation coefficient.Jander kinetic equation module is suited for carrying out the active energy in the moisture volatilization step and volatile organic compounds combustion step.In in-volatilization step,the Z-L-T equation is suited for carrying out the active energy.Jander equation module is suited for carrying out the active energy in fix carbon combustion.Considering the factors produced by NO_X in the process of sludge incineration,the effect of single factor conditions on the amount of NO_X produced by sludge incineration was analyzed under the conditions of different water content,different heating rates and different aeration conditions.The NO_X emission of sludge reached the maximum when the moisture content was about 50%.With the increase of heating rate,the NO_X emission of sludge decreases.As the amount of aeration increases,the amount of NO_X emissions increases,and the number of NO_X produced by the sludge incineration is not increasing and saturated when the volume of ventilation reaches 2L/min.In this paper,the NO_X emission of sewage sludge at different heating rates,different aeration rates and different moisture content is studied by orthogonal test.The results showed that ventilation capacity was the biggest factor affecting NO_X production.The influence factors of heating rate were the second,and moisture content had the least influence on sludge NO_X production.The influence factors of additive CaO on sludge incineration NO_X emission showed that the sludge NO_X emission increased when the Ca/S increased.When the ratio of Ca/S exceeded 1.4,the increase of NO_X increased in the sludge.When the Ca/S ratio of sludge exceeds 2.3,the yield of NO_X is very small.In addition,the experiment also proved that when the CaO was added to the sludge,the NOX precipitation temperature of the sludge moved forward. |
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