Research On Co-combustion Municipal Solid Waste With Oily Sludge

Oil sludge is a major waste generated during crude oil production,transportation,storage,and refining.According to the Directory of National Hazardous Waste,oil sludge fell into hazardous solid wastes.In China more than three million tones of oil sludge are generated annually.Incineration technology has many outstanding advantages,such as fast disposal speed,decreasing components efficiently and recycle energy as well.Oily sludge from different sources has great difference in composition and properties,which leads to incineration instability and difficult control of pollutants.The technical route of co-incineration of oily sludge and MSW?municipal solid waste?is proposed.This research considered the fundamental fuel properties and kinetics,its air pollutant emissions including NO,SO₂ and the numerical simulation of mixed co-combustion process are concerned.The co-combustion performance different blending ratios of oily sludge and MSW were investigated by thermogravimetric analysis.Through the Arrhenius equation and FWO model,analysis of kinetic parameters was obtained.The results showed that the comprehensive combustion index gradually decreases,with the increase of oil sludge mass fraction,while the average activation energy decreases first and then increases,in which the activation energy is minimum when the oil sludge mass fraction is 30%.According to results of both experiments and models,the appropriate ratio of oil sludge is about 10-30%.Study on the precipitation characteristics of NO and SO₂ in MSW and oily sludge by fixed bed with a tubular furnace.The results show that increasing the combustion temperature at 700?to 900?and decreasing oxygen concentration can reduce the amount of NO generated in the mixed samples,but increase the production of SO₂.After mixing oily sludge,the experimental conversion rate of NO and SO₂ is less than the calculated value,and increasing the mass fraction of oily sludge is beneficial to inhibiting the conversion of fuel N to NO and improving the sulfur fixation effect in the mixed combustion process.A typical MSW incineration thermodynamics model in Aspen Plus was built.Excess air,oil sludge ratios and moisture content on operating characteristics of incineration system were investigated.The results showed that the increase of the excess air coefficients and the proportion of oily sludge,reduced the temperature of incinerator temperature and NO_x emissions,but increased the SO_x emissions.The increase of primary air temperature has little effect on the incinerator temperature.But the water content of the oily sludge has a great influence on the temperature,the higher the water content and oil sludge mass fraction,the more obvious the decline of the incinerator temperature,NO_x and SO_x emission.The model can be a useful tool in both forecasting the operating parameters of MSW and oil sludge co-incineration.It can provide some references for the adjustment of incineration technology.