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971.
This paper sums up and analyzes the combined domestic wastewater treatment installation. The significance of existence and the effect of its treatment were affirmed. Some problems at present were pointed out. Suggestions on its research, manufacture and operation as well as its standardization and serialization are presented. 相似文献
972.
标准胶加工废水加水葫芦厌氧处理的研究 总被引:9,自引:0,他引:9
本文对标准胶加工废水和氧化塘种植的水葫芦厌氧发酵制取沼气进行了研究。结果表明,水葫芦是一种良好的沼气发酵原料,批量发酵每克干物质可生产沼气0.344L。常温下,水葫芦预发酵后与废水按1:3比例混合连续发酵,混合液每克COD可生产沼气0.556L,容积产气率达1.78L/(l.d)。为氧化塘种植的水葫芦提供了一个有效的处理方法。 相似文献
973.
天然纤维材料在工业废水中的应用 总被引:4,自引:0,他引:4
从化学改性的角度,对天然纤维材料在工业废水处理中的应用作一综述。 相似文献
974.
975.
禽畜废水厌氧反应动力学研究 总被引:1,自引:0,他引:1
为开发禽畜废水厌氧处理技术,利用外循环反应装置开展了畜禽废水厌氧反应动力学研究,以温度、基质COD值以及p H值为因素,设计了三因素三水平正交试验;引入温度参数,改进了Monod方程,建立了基质消耗、产物生成动力学模型;经线性、非线性回归,获得了模型参数,建立了相应的动力学方程,揭示了反应温度、基质COD值对反应速率的影响规律。研究表明:对基质消耗速率而言,反应活化能很低,可以忽略温度对反应速率的影响;温度对产物CH_4和CO_2的生成反应速率有影响,温度越高,越有利于CO_2的生成。建立的禽畜废水厌氧反应动力学模型能够较好地拟合试验数据,对厌氧反应器的开发设计具有参考价值。 相似文献
976.
977.
Krishnan Vijayaraghavan Desa Ahmad & Tariq Syahman Bin Fadzin 《Aquaculture Research》2008,39(5):449-456
This study presents an unconventional framework for treating shrimp aquaculture wastewater based on in situ hypochlorous acid (HOCl) oxidation. The in situ oxidation process makes use of the salinity present in aquaculture wastewater to generate HOCl. The undivided electrolytic cell consisted of two sets of graphite as the anode and stainless sheets as the cathode. The electrochemical oxidation of shrimp aquaculture wastewater was carried out for an influent COD concentration of 1730 mg L?1 at current densities of 37.2 and 74.5 mA cm?2. The results showed that in order to achieve a residual COD concentration of 50±5 mg L?1 at current densities of 37.2 and 74.5 mA cm?2, electrolysis periods of 60 and 30 min are required respectively. Hence, for the above‐mentioned current densities, the corresponding energy requirements were found to be 19.4 and 13.3 W h L?1. The cost incurred in treating 1 m3 of shrimp aquaculture wastewater was found to be RM 4 and 3 when the electrolytic reactor was operated at a current density of 37.2 and 74.5 mA cm?2 with a salinity of 23‰. The foregoing study highlights the potential of in situ HOCl oxidation in treating brackish shrimp aquaculture wastewater. 相似文献
978.
Comparative effects of food processing liquid slurry and inorganic fertilizers on tanner grass (Brachiaria arrecta) pasture: grass yield,crude protein and P levels and residual soil N and P 下载免费PDF全文
This small‐plot field study evaluated food processing liquid slurry (FPLS) as a potential fertilizer for tanner grass (Brachiaria arrecta) production on an acidic loam soil. The treatments, arranged in a randomized complete block design with three replicates, consisted of an unfertilized control, inorganic fertilizer applied at 50 and 200 kg nitrogen (N) ha?1 with and without phosphorus (P) at 50 kg P ha?1, and FPLS applied at 50 and 200 kg N ha?1. Compared to the unfertilized control, the FPLS applied at 200 kg N ha?1 significantly increased grass dry‐matter yield (DMY), herbage crude protein (CP) and P content, and N and P uptake in the second of two trials and P uptake in both trials. However, DMY and contents, of CP and P were generally lower for the FPLS treatments compared to the inorganic fertilizers. Apparent N recovery was higher for the inorganic fertilizer treatments than FPLS treatments in trial 1, while apparent P recovery was similar among all treatments in both trials. The FPLS treatments did not significantly increase soil NO3‐N and P concentrations, but increased NH4‐N in the 0–15 cm layer. The results suggest that application of FPLS to tanner grass pastures is an alternative to its disposal in landfill. 相似文献
979.
Soil properties and habitats determine the response of bacterial communities to agricultural wastewater irrigation 总被引:1,自引:0,他引:1
Sascha M. B. KRAUSE Anja B. DOHRMANN Osnat GILLOR Bent T. CHRISTENSEN Ines MERBACH Christoph C. TEBBE 《土壤圈》2020,30(1):146-158
Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in agroecosystems.However,the use of secondary treated wasterwater(TWW)could have consequences for the receiving soil environment and its resident microbial communities.The objective of this study was to characterize the importance of soil properties and habitats to the response of soil bacteria and archaea to irrigation with TWW.Two agricultural soils with contrasting textures(loamy sand or silt loam)and,for each,three variants differing in soil organic carbon and nitrogen,as generated by long-term fertilization,were analyzed.For each of these six soils,prokaryotic communities from two habitats,i.e.,root-free bulk soil and the rhizosphere of developing cucumber plants in the greenhouse,were characterized.Communities were analyzed by the quantity and diversity of their polymerase chain reaction(PCR)-amplified 16S rRNA genes.To account for TWW-associated nutrient effects,potable water(PW)served as a control.Amplicon sequence analysis showed that prokaryotic communities mainly consisted of bacteria(99.8%).Upon irrigation,regardless of the water quality,prokaryotic diversity declined,p H increased,and no bacterial growth was detected in bulk soil.In contrast,the growth of cucumbers was stimulated by TWW,indicating that plants were the main beneficiaries.Moreover,strong responses were seen in the rhizosphere,suggesting an indirect effect of TWW by altered rhizodepositions.The main bacterial responders to TWW were Proteobacteria,Bacteroidetes,Actinobacteria,and Planctomycetes.Changes in bacterial communities due to TWW were less pronounced in all variants of the silt loam,indicating the importance of clay and soil organic carbon for buffering effects of TWW on soil bacterial communities.Hence,soil organic carbon and soil texture are important parameters that need to be considered when applying TWW in agriculture. 相似文献
980.
为研究绿狐尾藻湿地对不同污染负荷养殖废水氮去除效应和影响因素,该研究在野外建立了9条表面流绿狐尾藻湿地,以低负荷(60 L/d废水+120 L/d清水)、中负荷(120 L/d废水+60 L/d清水/d)和高负荷(180 L/d废水)养殖废水为处理对象,研究了不同污染负荷下绿狐尾藻湿地水体氮素时间变化规律;结合线性混合模型,进一步探究了影响绿狐尾藻湿地氮去除的关键环境因子。结果表明,整个试验期间(2014-07-2015-05),绿狐尾藻湿地对低、中、高负荷废水铵氮(NH4+-N)和总氮(Total Nitrogen,TN)去除率均较高,其中NH4+-N平均去除率为85.0%~98.6%,TN平均去除率为83.6%~97.1%。线性混合模型分析结果表明,影响绿狐尾藻湿地NH4+-N去除的关键环境因子是水体溶解氧和硝态氮以及底泥NH4+-N含量,其中水体溶解氧对绿狐尾藻湿地NH4+-N去除影响最大。由于绿狐尾藻湿地对不同污染负荷废水NH4+-N和TN去除率均达到80.0%以上,因此绿狐尾藻可作为耐铵植物处理高负荷养殖废水。该研究结果可为绿狐尾藻湿地在规模养殖场的实际应用提供参考。 相似文献