| Currently, rational treatment and disposal for municipal sewage sludge has become one of the environmental problems perplexing the world. Compared with other treatment and disposal means, the technology of turning sludge into fuel has the advantages of resource and energy regeneration, and be widely applied in developed countries. With the rapid development of China’s economic and urbanization, urban sludge treatment and disposal more and more concerned. Sludge energy regenerated efficiently has become an urgent research topic in our country city sewage treatment.Taiyuan, B, H, Y wastewater treatment plants’mechanical dewatering sludge selected as the main raw material in this paper. Determined the scheme of the sludge conditioning by experiment on the basis of the analysis of the basic composition and the properties of the sludge. Experiment was arranged on sludge chemical drying medicament and sewage sludge-derived fuel molding conditioning sludge was taken as sample.At room temperature18℃, natural ventilation conditions, as after2min high-speed mixing the sludge drying effect is best, through the conditioning of sludge and sludge drying as a natural contrast curve obtained in the initial within4hours, conditioning the sludge, the average relative evaporation rate has improved significantly; in conditioning sludge as raw material, using orthogonal test of alternative chemicals for the ten water sludge drying effect analysis, synthesis finalized chemical sludge drying agent best ratio of CaO:MgO:CaO: MgO:Fe2(SO4)3:AlCl3:Al2(SO4)3=8:4:1:2:2,when the temperature20℃,natural ventilation, the effect is best when ratio of the dry agent and sludge dewatering is8:100,8h value dehydration within17.05g/100g.The result provides a theoretical basis for the sludge drying agent promoting.Due to its low calorific value and high ash. sludge is difficult to combust alone. After adding combustion-supporting materials (coal, straw, sawdust etc.) and rice straw and molding, the calorific value and volatile of SBF are similar to lignite and bituminous coal.Test results show that the sludge mixed fuel combustion content components fuel calorific value as oxidizer and gradually with the increase of adding amount of increase, the influence of pulverized coal is most significant, followed by straw and sawdust; The terms of the influence of strength of molding fuel drop, coal powder adding quantity influence the most significant, as falling coal powder added to increase strength increases, the test results to determine the best combination of compound oxidizer is straw:pulverized coal: sawdust=6:35:9.This topic of sludge drying test some conclusions and sludge derived fuel composition to determine the test results show that the sludge derived fuel optimal formula for sludge (water content75.2%):drying agent:mixed oxidizer (water content6.82%)=75:6:25,According to the forming of sludge derived fuel performance test results shows that adopt cold press molding process, falling strength as index, the optimum processing conditions are moisture content=13%, pressure=30MPa, diameter=15mm. |
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