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Cook KL Rothrock MJ Eiteman MA Lovanh N Sistani K 《Journal of environmental management》2011,92(7):1760-1766
Poultry litter is a valuable nutrient source for crop production. Successful management to reduce ammonia and its harmful side-effects on poultry and the environment can be aided by the use of litter amendments. In this study, three acidifiers, two biological treatments, one chemical urease inhibitor and two adsorber amendments were added to poultry litter. Chemical, physical and microbiological properties of the litters were assessed at the beginning and the end of the experiment. Application of litter amendments consistently reduced organic N loss (0-15%) as compared to unamended litter (20%). Acidifiers reduced nitrogen loss through both chemical and microbiological processes. Adsorbent amendments (water treatment residuals and chitosan) reduced nitrogen loss and concentrations of ammonia-producing bacteria and fungi. The use of efficient, cost-effective litter amendments to maximum agronomic, environmental and financial benefits is essential for the future of sustainable poultry production. 相似文献
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壳聚糖絮凝剂在活性污泥调理中的应用 总被引:14,自引:1,他引:14
研究了自制的壳聚糖絮凝剂在活性污泥调理中的应用,通过污泥比阻、上清液剩余浊度、泥饼含水率及沉降性能等的测定,重点分析了活性污泥脱水的pH范围、絮凝剂投量和壳聚糖分子量及其脱乙酰度对调理效果的影响,并与絮凝剂聚丙烯酰胺(PAM)和聚合氯化铝(PAC)作了比较,在此基础上还进行了双絮凝剂两段法处理污泥的初步探索。研究发现,壳聚糖作为活性污泥调理剂,投量(干污泥质量百分比)在0.8%~1.2%,pH值在5~8时即有较好的调理效果,与PAM效果基本相当,接近于8%~16%的PAC;壳聚糖相对分子量在30×10~4左右,脱乙酰度在70%左右时有较好的调理效果;双絮凝剂两段法处理污泥,在同等用量时效果好于单絮凝剂一段法。 相似文献
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壳聚糖对染料的吸附动力学研究 总被引:13,自引:0,他引:13
通过壳聚糖吸附酸性染料普拉蓝RAWL和阳离子蓝染料X-GRRL的试验,研究了壳聚糖对这两种水溶性染料吸附的动力学行为,包括吸附速率K和颗粒内有效扩散系数Di′,同时通过对吸附焓△H的试验计算,初步分析了它们的吸附机理。 相似文献
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武耀锋 《再生资源与循环经济》2014,(7):32-35
研究pH值、温度、反应物比率对生成三元接枝共聚物的影响,三元接枝共聚物接枝率与接枝效率的计算,以及三元接枝共聚物对铜离子的吸附效果.实验与计算结果表明:生成三元接枝共聚物的最佳反应条件为引发剂(NH4)2S2O8用量6 mmol/L,反应温度50℃,壳聚糖(CTS):丙烯酰胺(AM):丙烯酸(AA)=1∶2.7∶0.3,pH值=7,反应时间5h;在相同条件下,三元接枝共聚物对铜离子去除效果比壳聚糖有了明显的改善,对铜离子去除率最高达到90.06%,比壳聚糖对铜离子的去除率高49.72%. 相似文献
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Chitosan is a natural high molecular polymer made from crab, shrimp and lobster shells. When used as coagulant in water treatment, not like aluminum and synthetic polymers, chitosan has no harmful effect on human health, and the disposal of waste from seafood processing industry can also be solved. In this study the wastewater from the system of cleaning in place (CIP) containing high content of fat and protein was coagulated using chitosan, and the fat and the protein can be recycled. Chitosan is a natural material, the sludge cake from the coagulation after dehydrated could be used directly as feed supplement, therefore not only saving the spent on waste disposal but also recycling useful material. The result shows that the optimal result was reached under the condition of pH 7 with the coagulant dosage of 25 mg/l. The analysis of cost-effective shows that no extra cost to use chitosan as coagulant in the wastewater treatment, and it is an expanded application for chitosan. 相似文献
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The objective of this study was to investigate the effect of different Al species and chitosan (CS) dosages on coagulation performance, floc characteristics (floc sizes, strength and regrowth ability and fractal dimension) and membrane resistance in a coagulation–ultrafiltration hybrid process. Results showed that different Al species combined with humic acid in diverse ways. Ala had better removal efficiency, as determined by UV254 and dissolved organic carbon, which could be further improved by the addition of CS. In addition, the optimal dosage of different Al species was determined to be 4.0 mg/L with the CS concentration of 1.0 mg/L, by orthogonal coagulation experiments. Combining Ala/Alb/Alc with CS resulted in larger flocs, higher recovery, and higher fractal dimension values corresponding to denser flocs; in particular, the floc size at the steady state stage was four times larger than that obtained with Al species coagulants alone. The results of ultrafiltration experiments indicated that the external fouling percentage was significantly higher than that of internal fouling, at around 85% and 15%, respectively. In addition, the total membrane resistance was significantly decreased due to CS addition. 相似文献
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