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221.
The use of organic municipal wastes as soil amendments is an increasing practice that can divert significant amounts of waste from landfill, and provides a potential source of nutrients and organic matter to ameliorate degraded soils. Due to the high heterogeneity of organic municipal waste streams, it is difficult to rapidly and cost-effectively establish their suitability as soil amendments using a single method. Thermal analysis has been proposed as an evolving technique to assess the stability and composition of the organic matter present in these wastes. In this study, three different organic municipal waste streams (i.e., a municipal waste compost (MC), a composted sewage sludge (CS) and a thermally dried sewage sludge (TS)) were characterized using conventional and thermal methods. The conventional methods used to test organic matter stability included laboratory incubation with measurement of respired C, and spectroscopic methods to characterize chemical composition. Carbon mineralization was measured during a 90-day incubation, and samples before and after incubation were analyzed by chemical (elemental analysis) and spectroscopic (infrared and nuclear magnetic resonance) methods. Results were compared with those obtained by thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques. Total amounts of CO2 respired indicated that the organic matter in the TS was the least stable, while that in the CS was the most stable. This was confirmed by changes detected with the spectroscopic methods in the composition of the organic wastes due to C mineralization. Differences were especially pronounced for TS, which showed a remarkable loss of aliphatic and proteinaceous compounds during the incubation process. TG, and especially DSC analysis, clearly reflected these differences between the three organic wastes before and after the incubation. Furthermore, the calculated energy density, which represents the energy available per unit of organic matter, showed a strong correlation with cumulative respiration. Results obtained support the hypothesis of a potential link between the thermal and biological stability of the studied organic materials, and consequently the ability of thermal analysis to characterize the maturity of municipal organic wastes and composts. 相似文献
222.
针对500kV变电站内产生较高工频磁场强度的电气设备——35kV并联电抗器,研究不同类型、不同排列方式下35kV并联电抗器周围工频电磁场分布规律。结果表明,35kV并联电抗器的电磁场强度随着离开电抗器中心距离的增加而降低,三角形排列的电抗器磁场强度大于水平排列的。 相似文献
223.
钛白废酸固液分离与综合利用 总被引:2,自引:0,他引:2
介绍了湖南株洲化工集团有限责任公司钛白废酸固液分离与综合利用工艺。将钛白废酸固液分离后得到的清废酸用作磷肥生产用硫酸稀释液、钛白酸解工序硫酸稀释液和板框浸取液,取得了较好的经济效益和环境效益。 相似文献
224.
含碳氨水回收集成分离技术的研究与应用 总被引:1,自引:0,他引:1
在研究NH3-CO2-H2O三元体系基础上,将解吸、精馏和防结晶技术相结合,开发出集成分离技术,并成功地将其用于原有含碳氨水回收装置的改造,取得了十分显著的经济与环保效益。 相似文献
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用离子交换法从β盐母液中分离1-萘磺酸钠的研究 总被引:3,自引:2,他引:1
比较了D290、D296、D301、D370、D372、D380 6种树脂对β盐母液中1-萘磺酸的静态交换性能,筛选出D296用以回收β盐母液中的1-萘磺酸钠,进行了PH、接触时间、交换温度等影响因素的条件试验及树脂再生试验,得到1-萘磺酸钠收率80%以上。 相似文献
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采用模糊集的贴近度计算对齿轮表面探伤方法进行了优化选择,表明旋转磁场探伤是齿轮表面探伤的最佳方法,在实用中检测出大量的正在延伸扩展的表面疲劳裂纹. 相似文献
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