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1.
Composting and thermal drying are amongst the most commonly used post-digestion processes for allowing sanitation and biological stabilization of sewage sludge from municipal treatment plants, and making it suitable as soil conditioner for use in agriculture. To assess the impact of sludge-derived materials on soil microbial properties, fresh (LAF), composted (LAC) and thermally dried (LAT) sludge fractions, each resulting from a different post-treatment process of a same aerobically digested sewage sludge, were added at 1% (w/w) application rate on two contrasting (a loam and a loamy sand) soils and incubated under laboratory conditions for 28 days. Soil respiration, microbial ATP content, hydrolytic activities and arginine ammonification rate were monitored throughout the incubation period. Results showed that soil biochemical variables, including the metabolic quotient (qCO2), were markedly stimulated after sludge application, and the magnitude of this stimulatory effect was dependent on sludge type (precisely LAT > LAF > LAC), but not on soil type. This effect was related to the content of stable organic matter, which was lower in LAT. Genetic fingerprinting by PCR–DGGE revealed that compositional shifts of soil bacterial and, at greater extent, actinobacterial communities were responsive to the amendment with a differing sludge fraction. The observed time-dependent changes in the DGGE profiles of amended soils reflected the microbial turnover dependent on the sludge nutrient input, whereas no indications of adverse effects of sludge-borne contaminants were noted. Our findings indicate that composting rather thermal drying can represent a more appropriate post-digestion process to make sewage sludge suitable for use as soil conditioner in agriculture.  相似文献   
2.
剩余污泥臭氧化减量处置方法研究进展   总被引:1,自引:0,他引:1  
谭笑 《安徽农业科学》2015,(11):255-256
综合臭氧污泥减量化近年来的发展和研究,对其技术原理和工艺应用进行分析,提出了其现存问题,并讨论了未来的技术发展万向.  相似文献   
3.
厌氧消化系统中硫酸盐对重金属化学形态的转化作用   总被引:1,自引:0,他引:1  
本文对城市污水处理厂污泥厌氧消化过程中不同浓度的硫酸盐对铜、锌、镍三种重金属化学形态变化的影响进行了分析研究。结果表明,硫酸盐的存在能够促进污泥中重金属向稳定的硫化物形态转变。  相似文献   
4.
一种新的厌氧污泥比活性试验测定法   总被引:2,自引:0,他引:2  
赵亚乾 《中国沼气》1993,11(1):19-22
本文介绍了一种以医用血清瓶作发酵瓶、用医用注射器来量测所产沼气的厌氧污泥比活性试验测定法。实践表明此法简单实用、快速准确。  相似文献   
5.
杨瑞洪  刘丹 《安徽农业科学》2010,38(30):17015-17016
[目的]确定污泥最佳絮凝剂种类及其最佳的投加量和脱水工艺参数。[方法]针对石化企业污泥脱水工艺中存在的问题,以污泥沉降性能、污泥比阻和滤饼含水率为指标筛选出最佳絮凝剂,并通过正交试验对污泥脱水工艺进行优化。[结果]各因素对滤饼含水率的影响顺序为:搅拌水平〉投加量〉抽滤压力〉絮凝剂。最佳操作条件为絮凝剂K6728投加量2.0ml;搅拌水平150r/min 10s,50r/min 10min:过滤压力0.05MPa。各因素对污泥比阻的影响顺序为:搅拌水平〉抽滤压力〉投加量〉絮凝剂。最佳操作条件为絮凝剂K6728投加量2.5ml;搅拌水平150r/min 10s,50r/min 10min;过滤压力0.03MPa。综合分析得出最佳工艺参数为:K6728絮凝剂投加量2.0ml;搅拌水平150r/min 10s,50r/min 10min;过滤压力0.03MPa。此时,污泥脱水效果最佳。[结论]优化了石化污泥脱水工艺。  相似文献   
6.
A study was carried out to determine the influence of different types of sludges (municipal, industrial and residential) on field germination, growth and nodulation of L. leucocephala seedlings in the nursery. Before sowing of seeds, different combinations of sludges were incorporated with the nutrient deficient natural forest soils. Field germination, nodulation status and physical growth parameters of seedlings (shoot and root length, vigor index, collar diameter, leaf number, fresh and dry weight of shoot and root and total dry biomass increment) were recorded after three and six months of seed sowing. Field germination, nodulation status and growth parameters were varied significantly in the soil amended with sludges in comparison to control. The highest number of nodule was recorded from soil amended with residential sludge ( 1:1 ) and highest fresh and dry nodule weight was also found from the same combination in both three and six month old seedlings. In case of growth parameters, the highest growth was recorded from soil and residential sludge ( 1:1 ) combination compared to control. From the study, it can be recommended that soil amended with residential sludge ( 1:1 ) provide better field germination, growth and nodule formation of L. leucocephala in degraded soil.  相似文献   
7.
城市垃圾分类处理水平的高低是一个城市能否循环发展的民生大事,现阶段,我国城市污泥和园林绿地废弃物等有机垃圾制备有机肥技术仍不够完备。文章提出了三种有机垃圾混合处理方法和主要对比参数,提倡除技术处理和积极推广外,应政策性支持、支助城市有机垃圾就近利用和低成本、快速消纳转化技术,为城市生态健康、持久、平稳发展服务。  相似文献   
8.
Shrimp and fish pond soils: processes and management   总被引:7,自引:0,他引:7  
The pond bottom soil and the accumulated sediments are integral parts of ponds. Concentrations of nutrients, organic matter and microorganism density in the pond bottom are several orders of magnitude greater than in the water. The accumulation of organic sediments may limit pond intensification. The intensive organic matter degradation at the pond bottom and high sediment oxygen demand exceeds the oxygen renewal rate. This leads to the development of anoxic conditions in the sediments and at the sediment–water interface. A series of anaerobic processes, affected by the redox potential of the system, are taking place. A large number of potentially toxic materials are generated. Among those are organic acids, reduced organic sulfur compounds, reduced manganese and sulfides.

Shrimp, as animals that normally live on or near the bottom, are exposed to conditions on the pond bottom. Exposure to toxic materials endanger the well being of the cultured shrimp. Reduced feeding, slower growth, mortality and possibly higher sensitivity to disease are reported.

The rational use of aerators to minimize the area of sludge accumulation, construction of ponds to trap sludge, stirring sediments, chemical poising of the redox system and environmentally accepted treatment and reuse of drained sediments are means to control the conditions at the pond bottom.  相似文献   

9.
[目的]主要研究蚯蚓堆肥前后对污泥肥力和小白菜种子发芽情况的影响。[方法]利用蚯蚓堆肥处理污泥,通过测定堆肥前后污泥全氮、有效氮、全磷、有效磷、全钾、有效钾的变化,研究蚯蚓堆肥对污泥肥力的影响;利用堆肥处理后的污泥培养小白菜种子,通过测定发芽势、发芽指数和发芽率,研究堆肥后污泥肥力变化对其发芽率的影响。[结果]A1~A5(A2除外)试验组全氮下降幅度分别为27%、26%、21%和18%;A2组中全磷增加最大,为实验前的1.6倍;A2组中有效钾含量上升了20%;A5组中发芽率最低。[结论]蚯蚓堆肥提高了污泥中有效氮含量和全氮含量,而全磷含量、有效磷含量出现不同程度的增加,全磷增量大于有效磷,全钾和有效钾含量变化小;土壤中加入辅料对小白菜发芽势和发芽率均有不同程度的改善,发芽指数的变化趋势与发芽率一致。  相似文献   
10.
Summary In this study we evaluated the impact of five annual liquid sewage-sludge applications on the organic C and N content of a furrow-irrigated desert soil. Mineralization rates showed that sludge organic matter is mineralized rapidly (65% per year). Resistant residual sludge organic matter accumulation resulted in a theoretical increase in total soil organic C of 0.013% for the single sludge rate or 0.038% for three annual applications. These small additions were not detected in sludged soils at any depth to 270 cm. Similarly, increases in total soil N were not detected at any depth. However, soluble forms of organic C and N did increase in sludged soils relative to the non-sludged soils. In addition, soluble C:N ratios decreased significantly in the sludged soils. Soluble C and N also increased with depth due to leaching. This study therefore shows that applications of liquid sludge onto desert soils could affect the status of underground aquifers with respect to nitrate pollution.  相似文献   
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