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工厂化水体臭氧催化氧化法降解氨氮的水化学评价初报 总被引:1,自引:0,他引:1
在工厂化水产养殖过程中 ,氨氮是水生动物的主要代谢产物。水体中氨氮随着pH值和温度的变化 ,以离子氨和非离子氨形式存在 ,而非离子氨对水生动物具有高毒性 ,因此氨氮降解是工厂化高密度水产养殖生产中非常重要的水处理工艺过程。近年来国内外科研工作者在氨氮降解方面做了大量工作 ,研究了多种氨氮降解的方法 ,主要有离子交换法、生物膜法和臭氧氧化法等 ,但以上方法都存在氨氮降解不彻底、所需费用较高等缺陷 ,亟待开发更为有效的氨氮降解方法。臭氧氧化降解氨氮法虽具有同时对水体杀菌消毒的功效 ,但氨氮降解效率低于 3 0 % ,所以我们… 相似文献
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在鲑鳟鱼等冷水性鱼类的集约化养殖中,普遍发现氨作为一种污染因子,其毒性很大。如何控制和除去氨的毒性成为一个重要问题,摆在冷水性鱼类养殖者的面前。本文试将自己在实际养殖中的一些体会和试验结论,并参借有关文献作一总结,供同行参考。 一、氨毒性症状及造成氨中毒的原因 通过养殖池塘的对照试验,和日常对养殖水体的水质监测,我们发现非离子氨(即NH_3)浓度较高的池塘,冷水性鱼类表现的症状:鱼的生长速度慢,肥满度差,鳃及肾、肝组织发生不同程度的损害和病 相似文献
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采集海水虾蟹养殖池底泥,在以(NH4)2SO4为唯一氮源的选择性培养基上分离得到17株细菌,利用纳氏试剂分光光度法测定其氨氮降解能力,筛选出降解率较高的菌株X14-1-1。该菌株在氨氮质量浓度50mg/L时,72h内使氨氮质量浓度降至1.65mg/L,降解率可达96.7%;在氨氮质量浓度5mg/L时,72h内降解率可达74.01%。采用盐酸萘乙二胺分光光度法测定其降解亚硝酸盐的能力,结果显示,菌株X14-1-1在72h对亚硝酸盐的降解率达到67.2%。该菌株为革兰氏阴性短杆菌,大小为1.47~2.54μm×0.37~0.53μm,平板菌落呈乳白色,圆形。通过形态观察、生理生化试验及16SrDNA鉴定,初步确定X14-1-1属食油假单胞菌,命名为Pseudomonas oleovorans X14-1-1。该菌株在海水养殖环境水质调节及养殖废水处理方面具有潜在的应用价值。 相似文献
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冷水鱼循环水养殖中的低温氨氮处理技术研究 总被引:1,自引:0,他引:1
为解决冷水鱼养殖过程中养殖水体中的氨氮累积问题,根据低温生物滤器及臭氧催化氧化处理氨氮的特点,设计了冷水鱼工厂化养殖氨氮处理系统并进行了试验。试验基于以臭氧氧化为主、低温生物处理为辅的处理工艺,试验鱼为虹鳟鱼,养殖密度为23 kg/m3,试验水体约为10 m3,试验周期为7 d。结果表明,该系统能够满足冷水鱼工厂化养殖过程中有关氨氮处理的水质指标要求,处理后的养殖池进水口的水质指标总氨氮≤0.18 mg/L,硝酸盐氮氮≤29.43 mg/L,亚硝酸盐氮氮≤0.1 mg/L;养殖水体氨氮浓度监测表明,臭氧在水中残留低于0.008 mg/L,符合养殖鱼类对水体臭氧浓度的安全要求。 相似文献
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生物—电氧化法去除海水养殖循环水污染物 总被引:1,自引:0,他引:1
为提高海水养殖循环水处理效率,降低处理成本,本研究采用曝气生物滤器与电化学阳极氧化组合工艺,考察了不同阳极电势、进水氨氮和亚硝酸盐浓度下系统对氨氮及亚硝酸盐等污染物的去除效果,研究了微生物与工作电极之间的相互作用,并分析了电化学反应能耗。在水力停留时间为45 min、1.4 V阳极电压、进水氨氮和亚硝酸盐浓度分别为4.5和1.3 mg/L条件下,生物—电氧化法对氨氮去除率达88.8%,高出对照组7.6%,出水氨氮和亚硝酸盐浓度分别为0.5和0.9 mg/L,COD去除率为88.2%,高出对照组19.4%,平均能耗0.040 kWh/m3,电极表面微生物生长对阳极电氧化过程有促进作用,微生物功能预测显示实验组硝化功能占比为0.03%,对照组为0.07%。研究表明,生物—电氧化法对海水养殖循环水的污染物有良好的去除效果,具有一定的发展应用潜力。 相似文献
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Ongoing research in recirculation aquaculture focuses on evaluating and improving the purification potential of different types of filters. Algal Turf Scrubber (ATS) are special as they combine sedimentation and biofiltration. An ATS was subjected to high nutrient loads of catfish effluent to examine the effect of total suspended solids (TSS), sludge accumulation and nutrient loading rate on total ammonia nitrogen (TAN), nitrite and nitrate removal. Nutrient removal rates were not affected at TSS concentration of up to 0.08 g L?1 (P > 0.05). TAN removal rate was higher (0.656 ± 0.088 g m?² day?1 TAN) in young biofilm than (0.302 ± 0.098 g m?² day?1 TAN) in mature biofilm at loading rates of 3.81 and 3.76 g m?² day?1 TAN (P < 0.05), respectively, which were considered close to maximum loading. TAN removal increased with TAN loading, which increased with hydraulic loading rate. There was no significant difference in removal rate for both nitrite and nitrate between young and mature biofilms (P > 0.05). The ATS ably removed nitrogen at high rates from catfish effluent at high loading rates. ATS‐based nitrogen removal exhibits high potential for use with high feed loads in intensive aquaculture. 相似文献
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为提供实际生产理论依据,改良系统水处理工艺,开展循环水养殖系统中吉富罗非鱼氮收支和对水质情况的初步研究。起始养殖密度8 kg/m3,投饲率2%,系统循环量1 m3/h,总水量0.8 m3。试验期间溶解氧大于6 mg/L,pH 7.0~7.2,水温23~25℃。每周监测水质2~3次,监测指标包括氨氮、亚硝酸盐氮、硝酸盐氮,每2周检测1次水中总氮。用凯氏定氮法测定实验前后饲料、试验鱼体、粪便、悬浮颗粒的氮含量。结果显示,摄食氮有50.00±1.50%转化为生长氮,32.61±1.38%转化为排泄氮,17.39±4.0%转化为粪氮;58%的粪氮为悬浮颗粒物,42%为可沉淀颗粒物。 相似文献
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An integrated recirculating aquaculture system (RAS) for land-based fish farming: The effects on water quality and fish production 总被引:2,自引:0,他引:2
Shi-Yang ZhangGu Li Hui-Bi WuXing-Guo Liu Yan-Hong YaoLing Tao Huang Liu 《Aquacultural Engineering》2011,45(3):93-102
To mitigate the serious water pollution caused by the rapid expansion of the aquaculture industry in recent years, the development of improved aquaculture systems with more efficient water usage and less environmental impact has become essential. In this study, a land-based recirculating aquaculture system (RAS) was established that consisted of purification units (i.e., a primary biological pond, two parallel horizontal subsurface flow constructed wetlands [CWs], and a long ecological ditch) and 4-5 series-connected recirculating ponds. This system was mainly designed to stock channel catfish (Ictalurus punctatus), fifteen spine stickleback (Spinibarbus sinensis) and yellow catfish (Pelteobagrus fulvidraco), and the culture efficacy was evaluated based on a 2-year field experiment covering two growing seasons. According to the results, the primary biological pond played a role in sedimentation or nutrient retention, although this was not as evident when the CWs were functioning. The water flowing through the wetland system at a hydraulic loading rate (HLR) of 600 mm/day displayed lower values for the temperature, pH, dissolved oxygen (DO), suspended solids, organic matter and nutrients, whereas the electrical conductivity (EC) was higher, suggesting the accumulation of dissolved solids in the system. Due to the recirculation treatment, the trophic status of the recirculating ponds increased gradually along the direction of the flow and was notably lower in comparison to the control. As a result, the fish production responded to the variation of the water quality, which was reflected in the measurements of culture efficacy (final weight, survival rate, SGR and yield). The three main rearing species showed a decreasing trend along the direction of the flow, which was higher compared to the control, whereas an opposite trend was observed for filter-feeding fish. A Pearson correlation analysis revealed that the main culture species were inclined to live in meso- or oligotrophic conditions, and the silver carp adapted to more eutrophic conditions. Because RAS can provide better environmental conditions year-round, the present culture method could be more suitable for species that are sensitive to water quality in typical subtropical areas. 相似文献
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循环养殖系统中多级生物处理对水质的调控作用 总被引:2,自引:0,他引:2
研究了根据不同生物的功能特性及其间的协同作用,建立的由芦苇湿地、沉水植被群落、人工基质固定化微生物膜、软体底栖动物和滤食性鱼类组成的自净型多级生物修复系统,对养殖塘环境改善情况。结果显示:与实施修复前的系统相比,营养盐NO2-N、NO3-N和PO4-P的去除率分别达87.46%、62.99%和75.74%;浮游动、植物的生物量分别减少92.83%和15.90%。养殖塘排水营养盐NO2-N、NO3-N和PO4-P的去除率分别为27%~96%(年均87%)、37%~84%(年均84%)和30%~17%(年均9%),CODMn的去除率为1%~17%(年均9%)。经系统多级处理后水体透明度分别提高了75%和17%,最高值达52 cm。浮游植物生物量平均减少63.93%,尤其是蓝藻,平均减少68.17%。浮游植物群落结构转好,硅藻大量繁殖,成为优势种。浮游动物群落结构也由小型原生动物占优向大型枝角类、轮虫转变。受控于滤食性鱼类,浮游动物生物量维持在较低水平。 相似文献
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In order to realize the real-time appetite-based feeding in aquaculture, a novel and practical method, based on the quantification of the spontaneous collective behaviors, was proposed in this study to assess the real-time appetite of the swimming fish in a recirculating aquaculture system. First, foreground feature points of fish school were extracted using an improved complex network. Then, covariance, a modified social force model and a kinetic energy model were used to analyze the collective behaviors of the school from perspectives of dispersion degree, interaction force and the changing magnitude of the water flow field, respectively. Finally, the quantified behavioral characteristics were integrated and used to assess the appetite of fish school. The presented method shows its good performance in the expression of the collective behaviors representing five typical appetites (0.01, 0.52, 1.28, 2.26 and 2.92), and the assessing accuracy of the appetite of the school is also maintained at a low non-match rate ((2.19 ± 0.81)% best) in the context of ten different sampling durations. 相似文献