Based on the analysis of adsorptive features of oyster shells,the researches on the treatment of phosphorous wastewater with oyster shells and the effect of temperature on phosphorus removal were carried out.XRD was u...Based on the analysis of adsorptive features of oyster shells,the researches on the treatment of phosphorous wastewater with oyster shells and the effect of temperature on phosphorus removal were carried out.XRD was used to characterize the crystalline phases,and the main component of oyster shells was shown to be CaCO3.When the pretreatment temperature reached 800 ℃,some CaCO3 decomposed into CaO.As the temperature was further raised,CaO increased gradually.Via SEM testing,the oyster shell was a kind of natural porous materials.The pore wall partially collapsed from 550 to 900 ℃.No obvious porous structure was found at 900 ℃.However,without preheating,the oyster shell phosphorous removal material can not adsorb the phosphorus.Pretreatment made calcium activate,thus greatly increasing the absorption of phosphorus.展开更多
Investigations on the recycling plasma pyrolysis technique are presented in 25 kW was employed for the experiments. of oyster shells and bone waste treatment using the this paper. A arc based plasma torch operated at ...Investigations on the recycling plasma pyrolysis technique are presented in 25 kW was employed for the experiments. of oyster shells and bone waste treatment using the this paper. A arc based plasma torch operated at Fresh oyster shells were recycled using the plasma torch to convert them to a useful product such as CaO. Bone waste was treated to remove the infectious organic part and to vitrify the inorganic part. The time required for treatment in both cases was significantly short. Significant reduction in the weight of the samples was observed in both cases.展开更多
In this work,the effects of pH value of waste water and initial concentration of phosphorus on dephosphorization materials were investigated.The materials were prepared by shaping,sintering and hydrothermal reshaping ...In this work,the effects of pH value of waste water and initial concentration of phosphorus on dephosphorization materials were investigated.The materials were prepared by shaping,sintering and hydrothermal reshaping oyster shell and silica micro-powder.Different concentrations of phosphorus-contained waste water were simulated with potassium dihydrogen phosphate solution,the effect of dephosphorization was tested with phosphomolybdenum blue spectrophotometer method,and the crystal phase and microstructure of materials were characterized by XRD and SEM methods. It was indicated that dephosphorization was completed in 6 h when the initial phosphorus concentration in waste water was lower than 15 mg/L, and the dephosphorization time prolonged as the increase of phosphorus concentration. It was observed that the pH value of waste water influenced dephosphorization significantly, and neutral subalkalic environment favored dephosphorization. When the pH value was 11, the efficiency of dephosphozation was the greatest. For waste water with an initial concentration of 20 mg/L, the dephosphozation rate is close to 100% in8 h.展开更多
Oyster shell and cement were taken as the major raw materials to fabricate hollow, tubular and recoverable material for phosphorous removal （P removal） from waste water without sintering. In this paper, the effects ...Oyster shell and cement were taken as the major raw materials to fabricate hollow, tubular and recoverable material for phosphorous removal （P removal） from waste water without sintering. In this paper, the effects of different affecting factors on the sample P removal ratio were discussed to select optimal P removal process conditions. SEM and XRD were used to characterize the microscopic structures and composition of samples, and molybdenum blue spectrophotometry was applied to determine the P content in waste water. Results showed that at 30 ℃ for 2 d, the P removal ratio reached 93.3% when the cement content was 10 wt% and oyster shell powder was 90 wt%. SEM analysis revealed a flaky structure consisting of phosphorus-containing compound in the samples after P removal, and it piled on and maintained the porous structure. In addition, the results also suggested that raising the ambient temperature was benefit to the P removal. The P removal ratio of the material was optimal under neutral and alkali conditions.展开更多
基金Sponsored by the Fujian University New Century Excellent Talent Support Plan (No. XSJRC2007-17)
文摘Based on the analysis of adsorptive features of oyster shells,the researches on the treatment of phosphorous wastewater with oyster shells and the effect of temperature on phosphorus removal were carried out.XRD was used to characterize the crystalline phases,and the main component of oyster shells was shown to be CaCO3.When the pretreatment temperature reached 800 ℃,some CaCO3 decomposed into CaO.As the temperature was further raised,CaO increased gradually.Via SEM testing,the oyster shell was a kind of natural porous materials.The pore wall partially collapsed from 550 to 900 ℃.No obvious porous structure was found at 900 ℃.However,without preheating,the oyster shell phosphorous removal material can not adsorb the phosphorus.Pretreatment made calcium activate,thus greatly increasing the absorption of phosphorus.
文摘Investigations on the recycling plasma pyrolysis technique are presented in 25 kW was employed for the experiments. of oyster shells and bone waste treatment using the this paper. A arc based plasma torch operated at Fresh oyster shells were recycled using the plasma torch to convert them to a useful product such as CaO. Bone waste was treated to remove the infectious organic part and to vitrify the inorganic part. The time required for treatment in both cases was significantly short. Significant reduction in the weight of the samples was observed in both cases.
基金supported by the National Natural Science Foundation of China(21004024)the Province Natural Science Foundation of Fujian,China(2011J01046)+2 种基金the Program for New Century Excellent Talents in University of Fujian Province(2012FJ-NCET-ZR03)the University Distinguished Young Research Talent Training Program of Fujian Province(11FJPY02)the Promotion Program for Young and Middle-aged Teacher in Scienceand Technology Research of Huaqiao University(ZQN-YX103)~~
基金Supported by Fujian Science and Technology Administration (2004I003 and 20060037)
文摘In this work,the effects of pH value of waste water and initial concentration of phosphorus on dephosphorization materials were investigated.The materials were prepared by shaping,sintering and hydrothermal reshaping oyster shell and silica micro-powder.Different concentrations of phosphorus-contained waste water were simulated with potassium dihydrogen phosphate solution,the effect of dephosphorization was tested with phosphomolybdenum blue spectrophotometer method,and the crystal phase and microstructure of materials were characterized by XRD and SEM methods. It was indicated that dephosphorization was completed in 6 h when the initial phosphorus concentration in waste water was lower than 15 mg/L, and the dephosphorization time prolonged as the increase of phosphorus concentration. It was observed that the pH value of waste water influenced dephosphorization significantly, and neutral subalkalic environment favored dephosphorization. When the pH value was 11, the efficiency of dephosphozation was the greatest. For waste water with an initial concentration of 20 mg/L, the dephosphozation rate is close to 100% in8 h.
基金Sponsored by the 2007 Fujian University and College New Century Excellent Talent Support Program (No. XSJRC2007-17)Natural Science Foundation of Fujian Province of China(No. 2010J01279)
文摘Oyster shell and cement were taken as the major raw materials to fabricate hollow, tubular and recoverable material for phosphorous removal （P removal） from waste water without sintering. In this paper, the effects of different affecting factors on the sample P removal ratio were discussed to select optimal P removal process conditions. SEM and XRD were used to characterize the microscopic structures and composition of samples, and molybdenum blue spectrophotometry was applied to determine the P content in waste water. Results showed that at 30 ℃ for 2 d, the P removal ratio reached 93.3% when the cement content was 10 wt% and oyster shell powder was 90 wt%. SEM analysis revealed a flaky structure consisting of phosphorus-containing compound in the samples after P removal, and it piled on and maintained the porous structure. In addition, the results also suggested that raising the ambient temperature was benefit to the P removal. The P removal ratio of the material was optimal under neutral and alkali conditions.
