Research On The Drying And Incineration Characteristics Of Shenzhen Sewage Sludge

With the rapid development of economy, the accelerated urbanization process, urban sewage sludge production is increasing. Sludge is a kind of solid waste that has tremendous effects on the environment and human. Environment issues caused by significantly increasing in sludge production are also increasingly prominent. How effective, proper treatment and disposal of sludge to achieve a "reduction, stabilization, decontamination," disposal and recycling of energy which is the research focus within the area. This paper takes a series of experiments on sewage sludge from Shenzhen, including wet sludge drying and dry sludge incineration to verify Shenzhen sludge drying and incineration treatment technology is feasible. The research can provide a reference and basis of sludge drying and incineration for engineering applications.This paper introduces the basic properties of the sludge first, summed up the domestic and international methods commonly used in sludge treatment and disposal currently, and compare the advantages and disadvantages of various disposal methods that the sludge drying and incineration is an most effective and thorough treatment; then introduces the domestic and international research progress of the sludge drying and burning.A series experiments have been done on sludge from Shenzhen, including moisture content, proximate analysis, elemental analysis, energy analysis, the viscosity of sludge, heavy metals, sludge drying rate and dry Process gas emissions of pollutants. The results show that heavy metals in sewage sludge in Shenzhen is too high to be used in agriculture; high heat value, dehydration is good, can be incinerated after drying; apparent viscosity is small and can use sludge transfer pumps and other equipment to transfer sludge; condensation and activated carbon adsorption has a good effect on the removal of pollutants from the drying process.Sludge was combusted in 0.5MW Bubbling fluidized bed and 1MW circulating fluid bed and experimental conditions was 700℃,800℃and 900℃, pure sludge burning, burner used to maintain stability. Experiment has taken the fly ash and heavy metals in flue gas samples, incineration bottom ash and slag samples, testing the incineration process emissions of conventional air pollutants, dioxins and other pollutants emissions. The results show that the heavy metal contented in the flue gas fly ash is not high; CO, SO2, NOx emissions are greater so that flue gas treatment equipment should be used to capture fly ash and control the secondary pollutant; TEQ dioxin emissions are much lower than the national standard, and with the burning temperature increase, the emission of dioxins reduce.