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231.
三阶段温度控制堆肥接种法对有机氮变化规律的影响 总被引:1,自引:0,他引:1
利用原生生活垃圾,通过三阶段温度控制技术进行堆肥试验,探讨在堆肥过程中有机态氮组分的动态变化规律.结果表明,全氮、酸水解有机态氮、氨基酸态氮均在堆肥的前期呈明显的下降趋势,呈较好的相关性.与CK(对照组)处理相比,在堆肥的后期,三阶段温度控制堆肥酸水解有机态氮、氨基酸态氮、氨基糖态氮及酸解未知态氮含量呈不同程度的上升趋势,增加幅度依次为:10.67%、16.17%、7.17%、22.44%.表明三阶段温度控制技术能减少堆肥中氮素的损失,堆肥产品施入土壤后,可提高土壤的供氮潜力. 相似文献
232.
研究了3种巯基捕收剂,二乙基二硫代氨基甲酸钠(乙硫氮)、乙基黄原酸钾(乙基黄药)和二丁基二硫代磷酰铵(丁铵黑药),对垃圾焚烧飞灰中重金属的稳定化效果。3种巯基捕收剂的用量均为62.5μmol?g-1飞灰。扫描电镜观察发现,飞灰经稳定化处理后,巯基捕收剂均匀地覆盖于飞灰晶体表面,使矿物晶体棱角变得模糊。利用酸浸提程序(TCLP法)和水浸提程序(水平振荡法)评价飞灰中重金属Cu、Pb、Cd、Cr和Zn的浸出毒性。在0.1mol?L-1醋酸浸提条件下,与Na2S相比,巯基捕收剂对Cu和Pb的稳定化效果较好,其中乙硫氮对Cu的稳定化比率接近100%,丁铵黑药对Pb的稳定化比率达到69.2%;在水浸提条件下,乙硫氮、乙基黄药和丁铵黑药对5种重金属的稳定化比率分别为72.6%、73.5%和76.8%,显著高于Na2S处理(52.4%)。三种巯基捕收剂对5种重金属亲和力的强弱顺序大致为Cu>Pb>Cr>Cd>Zn,并且超过60%的巯基捕收剂与酸可浸提重金属离子发生了螯合沉淀反应。重金属-巯基捕收剂絮凝物在中性和碱性条件下(pH>6)比较稳定,在酸性条件下(pH<6)可发生部分溶解。为获得较好的重金属稳定化效果,维持稳定化飞灰的高酸缓冲容量十分重要。 相似文献
233.
浅析电子废弃物回收利用及危害解决办法 总被引:1,自引:0,他引:1
随着高科技的发展和人们需求的增长,电子产品不断推陈出新,电子废弃物成为世界上数量增长最快的垃圾."电子垃圾",主要包括各种使用后废弃的电脑、通信设备、电视机、电冰箱、洗衣机等电子电器产品.电子废弃物不规范回收处理易造成污染.电子废弃物中含有很多可回收再利用的有色金属、黑色金属、玻璃等物质.严格意义上讲,这些电子废弃物,不应称其为电子垃圾,而应称作电子旧货.伴随着电子工业的高速发展,电子废弃物污染不可避免地摆在了我们面前.电子废弃物具有危害性和可利用性. 相似文献
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236.
Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to
improve thermophilic anaerobic digestion efficiency. Uniform design was applied to determine the combination of target temperature
(110–210°C), microwave holding time (1–51 min), and NaOH dose (0–2.5 g NaOH/g suspended solids (SS)) in terms of their effect
on volatile suspended solids (VSS) solubilization. Maximum solubilization ratio (85.1%) of VSS was observed at 210°C with 0.2
g-NaOH/g-SS and 35 min holding time. The effects of 12 different pretreatment methods were investigated in 28 thermophilic batch
reactors by monitoring cumulative methane production (CMP). Improvements in methane production in the TWAS were directly related
to the microwave and alkaline pretreatment of the sludge. The highest CMP was a 27% improvement over the control. In spite of the
increase in soluble chemical oxygen demand concentration and the decrease in dewaterability of digested sludge, a semi-continuous
thermophilic reactor fed with pretreated TWAS without neutralization (at 170°C with 1 min holding time and 0.05 g NaOH/g SS)
was stable and functioned well, with volatile solid (VS) and total chemical oxygen demand (TCOD) reductions of 28% and 18%,
respectively, which were higher than those of the control system. Additionally, methane yields (L@STP/g-CODadded, at standard
temperature and pressure (STP) conditions of 0°C and 101.325 kPa) and (L@STP/g VSadded) increased by 17% and 13%, respectively,
compared to the control reactor. 相似文献
237.
Manuela Anzano Alessandra Tosti Marina Lasagni Alfredo Campiglio Demetrio Pite Elena Collina 《环境科学学报(英文版)》2011,23(9):1570-1577
The aim of the research was to develop new products and processes from a manufacturing waste from an Italian metallurgic company. The company produced thin silver metallic films and the production scraps were silver flakes. The possibility to use the silver flakes in water disinfection processes was studied. The antimicrobial activity of the flakes was investigated in batch using Escherichia coli as Gram-negative microorganism model. The flakes did not show any antimicrobial activity, so they were activated with two different processes: thermal activation in reducing atmosphere and chemical activation, obtaining, respectively, reduced flakes (RF) and chemical flakes (CF). The flakes, activated with either treatment, showed antimicrobial activity against E. coli. The kill rate was dependent on the type of activated flakes. The chemical flakes were more efficient than reduced flakes. The kill rate determined for 1 g of CF, 1.0 ± 0.2 min−1, was greater than the kill rate determined for 1 g of RF, 0.069 ± 0.004 min−1. This was confirmed also by the minimum inhibitory concentration values. It was demonstrated that the antimicrobial capability was dependent on flakes amount and on the type of aqueous medium. Furthermore, the flakes maintained their properties also when used a second time. Finally, the antimicrobial activities of flakes were tested in an effluent of a wastewater treatment plant where a variety of heterotrophic bacteria were present. 相似文献
238.
Aged refuse from waste landfills closed for eight years was examined and found to contain rich methanotrophs capable of biooxidation
for methane. Specially, community structure and methane oxidation capability of methanotrophs in the aged refuse were
studied. The amount of methanotrophs ranged 61.97 103–632.91 103 cells/g (in dry basis) in aged refuse from Shanghai Laogang
Landfill. Type I and II methanotrophs were found in the aged refuse in the presence of sterilized sewage sludge and only Type I
methanotrophs were detected in the presence of nitrate minimal salt medium (NMS). The clone sequences of the pmoA gene obtained
from the aged refuse were similar to the pmoA gene of Methylobacter, Methylocaldum, and Methylocystis, and two clones were distinct
with known genera of Type I methanotrophs according to phylogenetic analysis. Aged refuse enriched with NMS was used for methane
biological oxidation and over 93% conversions were obtained. 相似文献
239.
240.