The influence of fly ash(FA)applied alone and/or with sewage sludge(SS)on wheat(Triticum vulgare)grain yield,biomass production and soil properties was studied in a field experiment.The results showed that both FA and...The influence of fly ash(FA)applied alone and/or with sewage sludge(SS)on wheat(Triticum vulgare)grain yield,biomass production and soil properties was studied in a field experiment.The results showed that both FA and SS significantly increased grain yield and plant biomass.FA applied alone increased significantly soil pH and EC while FA applied together with SS did not significantly affect them compared to mono FA treatment.Soil pH and EC values increased with time in FA and FA-SS treatments.SS increased soil organic matter and total N content and SS applied together with FA increased also available soil B.From the plant nutrients tested only tissue N concentration was increased significantly in all treatments compared to control.Copper,Zn,Mn,Ni,and Pb at both available and total concentrations are significantly affected.展开更多
The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of se...The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of sewage sludge and coal,and non-isothermal kinetics analysis method was applied to evaluate the combustion process.Based on Coats-Redfern integral method,some reaction models were tested,the mechanism and kinetics of the combustion reaction were discussed.The results show that the combustion of sewage sludge is mainly in the low temperature stage,meanwhile the ignition temperature and Arrhenius activation energy are lower than that of coal.The combustion of sewage sludge has the advantage over coal in some aspects,thus sewage sludge can partly replace coal used as cement industry fuel.展开更多
The influences of dewatered sludge blending ratio in coal on flammability index （C） and combustion characteristic index （S） and release of sulfur dioxide （SO2）, nitrogen oxide （NOx）, carbon monoxide （CO） and...The influences of dewatered sludge blending ratio in coal on flammability index （C） and combustion characteristic index （S） and release of sulfur dioxide （SO2）, nitrogen oxide （NOx）, carbon monoxide （CO） and heavy metals （Hg, As, Cd, Pb and Cr） were studied. The impact on combustion characteristics could be ignored if less than 20% of dewatered sludge was added in coal. Besides, emission pattern experiments of NOx, SO2, CO and heavy metals were carried out in a high-temperature tubular furnace. Results showed that the conversion rate of NOx and total emission of SO2 reduced with the increase of sludge adding ratio, and a better effect of fixing sulfur could be obtained when the blending ratio reached 30%. Concentrations and distributions of five types of heavy metals in different residues （bottom ash and fly ash） as well as in flue gas were analyzed. It was shown that the characteristics of coal and sludge, as well as the volatilization of heavy metals had a great influence on the distribution of heavy metals.展开更多
文摘The influence of fly ash(FA)applied alone and/or with sewage sludge(SS)on wheat(Triticum vulgare)grain yield,biomass production and soil properties was studied in a field experiment.The results showed that both FA and SS significantly increased grain yield and plant biomass.FA applied alone increased significantly soil pH and EC while FA applied together with SS did not significantly affect them compared to mono FA treatment.Soil pH and EC values increased with time in FA and FA-SS treatments.SS increased soil organic matter and total N content and SS applied together with FA increased also available soil B.From the plant nutrients tested only tissue N concentration was increased significantly in all treatments compared to control.Copper,Zn,Mn,Ni,and Pb at both available and total concentrations are significantly affected.
文摘The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of sewage sludge and coal,and non-isothermal kinetics analysis method was applied to evaluate the combustion process.Based on Coats-Redfern integral method,some reaction models were tested,the mechanism and kinetics of the combustion reaction were discussed.The results show that the combustion of sewage sludge is mainly in the low temperature stage,meanwhile the ignition temperature and Arrhenius activation energy are lower than that of coal.The combustion of sewage sludge has the advantage over coal in some aspects,thus sewage sludge can partly replace coal used as cement industry fuel.
文摘The influences of dewatered sludge blending ratio in coal on flammability index （C） and combustion characteristic index （S） and release of sulfur dioxide （SO2）, nitrogen oxide （NOx）, carbon monoxide （CO） and heavy metals （Hg, As, Cd, Pb and Cr） were studied. The impact on combustion characteristics could be ignored if less than 20% of dewatered sludge was added in coal. Besides, emission pattern experiments of NOx, SO2, CO and heavy metals were carried out in a high-temperature tubular furnace. Results showed that the conversion rate of NOx and total emission of SO2 reduced with the increase of sludge adding ratio, and a better effect of fixing sulfur could be obtained when the blending ratio reached 30%. Concentrations and distributions of five types of heavy metals in different residues （bottom ash and fly ash） as well as in flue gas were analyzed. It was shown that the characteristics of coal and sludge, as well as the volatilization of heavy metals had a great influence on the distribution of heavy metals.
