甘蔗渣载体填料在海水曝气生物滤池中的应用

为研究甘蔗渣作为载体填料用于海水曝气生物滤池中的可行性,在海水曝气生物滤池中培养生物膜,并以此为基础构建海水养殖排放水处理系统。通过监测水体总氨氮(TAN)、亚硝酸盐氮(NO2--N)等水质指标浓度变化,水体游离细菌与载体附着细菌密度变化,评价甘蔗渣载体生物滤池的降解效果。结果显示,以甘蔗渣为载体的生物滤池挂膜所需时间为26 d,挂膜完成后甘蔗渣附着可培养总菌和芽孢杆菌密度分别为3×108cfu/g和7.8×107cfu/g。在处理养殖水体时,生物滤池中水体氨氮和亚硝酸盐氮浓度分别控制在0.2 mg/L和0.05 mg/L以下,同时,水体中芽孢杆菌数量由3.3×103cfu/L增加至7×104cfu/L,弧菌数量由4.9×103cfu/L下降至3.1×101cfu/L。研究表明,以甘蔗渣为载体的海水曝气生物滤池能快速有效地完成挂膜,并在海水养殖排放水处理中取得较好效果。     

竹子填料海水曝气生物滤器除氮性能

生物滤器是循环水养殖系统的关键水处理单元,主要用于去除水体中水溶性的氮化物.采用人工模拟海水养殖废水,在系统运行的水力停留时间HRT为1h,水温为18～25 ℃,气水比为3∶1,初始C/N＝3∶1,pH为8.05～8.53条件下,对竹子填料浸没式生物滤器的挂膜过程和稳定运行阶段系统去除氨氮的运行特性,以及挂膜过程中的硝化细菌群落变化进行了实验研究.结果表明,在较低的NH+4-N浓度条件下,采用竹子填料的生物滤器有较快的挂膜速度,挂膜成功后滤料表面上生长的氨氧化细菌和亚硝酸氧化细菌的数量分别为4.5×105、1.5×105(光面)和1.1×106 CFU/ml(粗面).具有较高且稳定的氨氮去除效果,氨氮去除效率达到80%,出水浓度小于0.06 mg/L,满足海水循环养殖系统中的应用要求.     

pH对海水生物滤器启动阶段构建硝化功能的影响

稳定高效运行的生物滤器是循环水系统养殖过程中至关重要的部分,然而生物滤器在运行过程中会受到诸多环境因子的影响。该文分两部分对进水pH对流化床生物滤器硝化性能的影响进行研究。(1)针对流化床生物滤器挂膜启动阶段进行研究,研究在自然挂膜情况下,不同进水pH(7. 0、7. 5、8. 0、8. 5)对流化床生物滤器启动的影响,结果显示,生物滤器在pH 7. 5时启动时间最短,50 d左右便能够稳定运行,而且在此pH条件下生物滤器对TAN、NO2--N的去除效率最高。(2)生物膜成熟后,针对稳定运行的生物滤器进行试验,研究不同pH(7. 0、7. 5、7. 7、8. 0、8. 5)对生物滤器硝化性能的影响,结果显示,生物滤器在pH 7. 7时,对TAN的去除速率最高,达到(0. 58±0. 02) mg/(L·h)。另外,生物滤器在pH 7. 5时对NO2--N的处理效果最好。试验还发现各处理组皆存在不同程度的NO2--N积累现象,该现象随着pH的升高不断加剧。适宜的进水pH能够缩短生物滤器的挂膜周期并提高其硝化性能。研究结果可以为海水生物滤器的挂膜启动和稳定运行提供理论指导。     

高效脱氮菌强化挂膜生物滤器对海水养殖尾水净化效果研究

为了提高海水养殖尾水的净化效率,研究了利用高效脱氮菌强化挂膜后的生物滤器对静止和流动养殖尾水的净化效果.首先利用自主筛选的3株适应海水环境、可有效去除氨氮、亚硝酸氮及有机物的高效脱氮菌[花津滩芽孢杆菌(Bacillus hwajinpoensis)SLWX2、嗜碱盐单胞菌(Halomonas alkaliphila)X...     

国外渔业文摘

<正>黑棘鲷养殖系统中臭氧剂量对总残留氧化剂、氮化合物和硝化率的影响在海水循环水养殖系统(RAS)中施加臭氧以测定其对水质和生物滤器效率的影响。本研究使用了3个完全相同的实验系统。对照系统(CS)没做臭氧处理,而实验组1(T20)和实验组2(T40)则分别施以20和40 g O3/kg feed/d作臭氧处理。实验养殖为期44 d,在此期间对各系统的总残留氧化剂(TRO)、氮化合物(总氨氮、亚硝态氮和硝态氮)进行了测定,并计算了生物滴滤池的硝化率。总体上来讲,在海水系统作臭氧处     

几种环境因子对循环水养殖系统中生物膜净化效率的研究

为研究环境因子对生物膜水质净化效果,对爆炸棉为滤料的生物滤器进行了试验。采用优势菌种挂膜后,在不同水温、溶氧(DO)、盐度、p H条件下,研究生物滤器对人工加富的海水养殖废水水质的净化效果。结果显示,水温28℃时,化学需氧量(CODMn)、氨氮(NH4+-N)、亚硝酸盐氮(NO2--N)、磷酸盐(PO43--P)去除率分别为69.3%、93.7%、93.7%、19.4%;DO 6.00 mg/L时,CODMn、NH4+-N、NO2--N、PO43--P去除率分别为72.8%、91.7%、97%、15.6%;盐度25时,CODMn、NH4+-N、NO2--N、硝酸盐氮(NO3--N)、PO43--P去除率分别为57.1%、98.4%、99.9%、100%、42%;p H 7.5时,CODMn、NH4+-N去除率分别为72.8%、93.3%。研究表明,水温28℃、DO 6.00mg/L、盐度25和p H 7.5为该生物滤器最适水质净化条件,此时生物膜净化效率较高,出水水质较好。     

养殖尾水氮元素在海水人工湿地中的迁移转化过程

为深入探究养殖尾水中氮元素在海水人工湿地内的迁移转化过程,以牙鲆(Paralichthys olivaceous)养殖尾水为研究对象,利用氮稳定同位素技术示踪氮的迁移转化,并采用质量平衡法定量不同脱氮途径对人工湿地脱氮的贡献,以全面评估人工湿地系统的脱氮能力。结果表明,复合垂直流人工湿地对硝态氮有较好的处理效果。经21 d循环运行, NO3--N氮去除率可达(92.81±1.21)%,湿地各基质层中煤渣层δ15N值最低,为(203.58±2.87)‰,珊瑚石层δ15N值最高,为(303.66±2.22)‰;植物中氮含量显著高于各层基质氮含量,平均氮含量为(2.68±0.38)%,其单位质量吸收氮素的能力最强,绝对丰度平均值为(105.61±14.65)×10-3 mg/g,远高于各基质层。系统初期基质、植物及微生物转化对系统脱氮的贡献率分别为44.70%、21.90%、18.11%;稳定期微生物转化则成为主要脱氮途径,贡献率高达60.77%,基质贡献率为6.46%。本研究结果全面揭示了海水养殖尾水中氮元素的去除效率和迁移转化过程,可为氮稳定同位素技术在海水人工湿地系统中的应用提供有效的...     

碳源及C/N对复合菌群净化循环养殖废水的影响

为了解决循环养殖废水水质处理过程中存在的脱氮碳源不足问题,从而提高整个循环养殖废水生物脱氮效率.实验以高NO3-N降解能力和低NO2--N积累量为碳源优化指标,研究了乙醇、丙三醇、葡萄糖、蔗糖、乙酸钠和酒石酸钾钠6种碳源及不同碳氮比(C/N)对复合菌群净化循环养殖废水效果的影响.碳源初筛结果显示,当以葡萄糖、蔗糖等糖类物质为外加碳源时,实验过程中NO2--N积累现象较明显,最高可达12.4 mg/L;当以醇类物质为外加碳源时,NO2--N积累量较低,最高也只有1.3 mg/L.碳源复筛结果显示,不同碳源及C/N对养殖废水的NH4+-N去除率并无显著差异,且各处理组的NH4+-N去除率高达98.2％,显著地高于对照组(P＜0.05);以乙醇为外加碳源且C/N为3∶1时,复合菌群对养殖废水的TN、NH4+-N和NO3--N去除率分别高达93.3％、98.9％和91.8％,均显著地高于对照组(P＜0.05).综合考虑外加碳源的实用性和经济性等因素,选取乙醇作为复合菌群净化养殖废水的外加碳源,相应的C/N为3∶1.虽然外加碳源短期内会引起水体CODMn含量大幅升高,但可被复合菌群迅速降解;此外,外加碳源还能改善水体pH值,经处理组净化后的水体pH值维持在7.2～7.8.结果表明,循环养殖废水水质净化过程中添加相应的碳源并适当控制C/N能显著改善池水水质,提高生物脱氮效率.     

生物—电氧化法去除海水养殖循环水污染物

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。     

海水养殖尾水人工湿地处理系统及其脱氮过程研究进展和展望

利用人工湿地处理海水养殖尾水具有很大的应用前景,其中,脱氮是人工湿地的主要任务之一。基质上栽培的植物和附着的微生物参与的氮循环是人工湿地生物脱氮的主要路径,植物和多种氮代谢菌群在人工湿地内部相互协同与制约,构成了一个复杂的氮代谢网络。海水养殖尾水的高盐度和低碳氮比(C/N)又决定了此类人工湿地独特的处理环境和生物脱氮机制。同时,人工湿地的供氧模式、水力负荷(HRT)、水力停留时间(HLR)等水力条件参数对脱氮效能也有很大影响,对这些指标进行调控和优化,可以提高湿地的整体脱氮性能。本文从海水人工湿地的构建、基质的选取、耐盐植物的筛选、氮循环相关微生物以及运行参数调控四个方面,对近年来海水养殖尾水人工湿地生物脱氮方面的研究进展进行了综述和展望,以期为深入理解海水人工湿地脱氮机制和优化运行方式提供参考。     

循环水养殖系统生物滤器负荷挂膜技术

循环水养殖系统启动运行前往往需要经过一段时间的生物膜预培养,使生物膜达到成熟稳定,从而保证系统的水质净化功能。本研究通过养殖试验,研究了生物滤器负荷挂膜的技术方法,以期实现生物膜的快速成熟和系统的快速启动。为此,构建了6组循环水系统组成的养殖车间,建成后立即投入试验生产。试验为期120 d,养殖种类为红鳍东方鲀,初始放养平均体重(632.5±2.26)g。期间,红鳍东方鲀平均增重29.91%,养殖成活率98.7%,养殖密度由(19.34±1.89)kg/m3增加到(32.17±3.40)kg/m3,投饵率由0.2%增加到0.5%–0.7%,每日换水量由50%逐渐减至10%。结果表明,在生物膜的生长期,通过对投饵量及新水补充量的有效调节,可以把养殖水体中的氨氮和亚硝氮浓度控制在安全范围以内,以保证养殖鱼类的生长。生物膜在50天左右达到完全成熟,此后便可依靠生物膜的净化作用将氨氮浓度控制在0.5?1.2 mg/L、亚硝氮浓度控制在0.2?0.5 mg/L、pH值控制在6.5–7.5、COD值低于4 mg/L、细菌总数控制在800–2100 cell/ml的安全范围内。利用生物滤器负荷挂膜技术,在合理调控水质指标的条件下,循环水养殖系统建成后可以立即投入生产,实现生物滤器挂膜与养殖生产的同步进行。     

Efficiency of biofloc technology in suspended growth reactors treating aquacultural solid under intermittent aeration

Aquacultural solid waste from a recirculation aquaculture system was used as a substrate to produce heterotrophic bacteria in suspended growth reactors. The efficiency of nitrogen recycling under intermittent aeration (IA, 0.5-h aeration/0.5-h non aeration) and continuous aeration (CA) strategy was investigated. The nitrogen dynamics, biochemical composition of biofloc and efficiency of nitrification/denitrification/ammonium assimilation of biofloc were determined. No significant differences were observed in the nitrogen recycling rate, crude protein and polysaccharides contents of biofloc between the IA and CA reactors. The energy used for intermittent aeration was almost one half of that for continuous aeration. IA strategy (0.5-h aeration/0.5-h non aeration) appears to be more effective to produce biofloc in aquaculture solid waste in reactors than CA strategy.     

Potential applications of biological filtration media in changing water properties and subsequent effects on common carp (Cyprinus carpio) in recirculating aquaculture systems

This work aims to develop a suitable aquaculture system to solve issues pertaining to water quality in recirculating aquaculture systems (RAS) thereby improving fish growth performance and their feed conversion ratio (FCR). It is known that the efficiency of nutrient decomposition depends on the amount and species of bacteria present in the filter, and these can in turn be regulated by the pH. Our study shows that the significant increase in pH from 7.45 to 7.51 and 7.47 is achieved after the water was filtered through sawdust and wood wool respectively. At the same time, nitrite concentrations were found to have significantly decreased from 0.06 ppm in the control to 0.01 ppm in the sawdust treatment. Changes in the physical–chemical properties of treated water affect the biological properties of the organisms. It was found that the average final body weight for fish in the wood wool treatment 30.96 g and fish in the sawdust treatment 31.44 g was significantly higher compared to that for the fish in the control treatment 28.42 g. The use of sponge, wood wool or sawdust resulted in significantly lower FCR and therefore better fish productivity in RAS. At the same time, the red blood cell count, plasma urea, plasma creatinine, plasma albumin, and GOT and GPT were significantly higher in fish in the plastic, sponge, wood wool or sawdust treatment compared to the control treatment. In summary, this study demonstrates the benefits of using sponge, wood, wool and sawdust as biofilter media for aquaculture.     

Performance and operation of a rotating biological contactor in a tilapia recirculating aquaculture system

This paper describes the performance characteristics of an industrial-scale air-driven rotating biological contactor (RBC) installed in a recirculating aquaculture system (RAS) rearing tilapia at 28 °C. This three-staged RBC system was configured with stages 1 and 2 possessing approximately the same total surface area and stage 3 having approximately 25% smaller. The total surface area provided by the RBC equaled 13,380 m². Ammonia removal efficiency averaged 31.5% per pass for all systems examined, which equated to an average (± standard deviation) total ammonia nitrogen (TAN) areal removal rate of 0.43 ± 0.16 g/m²/day. First-order ammonia removal rate (K₁) constants for stages 1–3 were 2.4, 1.5, and 3.0 h⁻¹, respectively. The nitrite first-order rate constants (K₂) were higher, averaging 16.2 h⁻¹ for stage 1, 7.7 h⁻¹ for stage 2, and 9.0 h⁻¹ stage 3. Dissolved organic carbon (DOC) levels decreased an averaged 6.6% per pass across the RBC. Concurrently, increasing influent DOC concentrations decreased ammonia removal efficiency. With respect to dissolved gas conditioning, the RBC system reduced carbon dioxide concentrations approximately 39% as the water flowed through the vessel. The cumulative feed burden – describes the mass of food delivered to the system per unit volume of freshwater added to the system daily – ranged between 5.5 and 7.3 kg feed/m³ of freshwater; however, there was no detectable relationship between the feed loading rate and ammonia oxidation performance.     

自动增氧型人工湿地除氮果研究

本试验针对人工湿地内部溶解氧浓度不足的问题,利用页岩空心砖构建自动增氧型湿地系统,研究构建系统对氮的净化效率。实验结果表明：构建自动增氧型湿地系统各基质层污水溶解氧浓度均在 0.5 mg/L以上,泥土、粉煤灰和砾石三层基质对 TN 的去除率分别达到了38.9%、33.2%和22.9%,构建的自动增氧型湿地系统净化效果略好于人工强化供氧湿地系统。故可利用页岩空心砖构建自动增氧型湿地系统,以增强湿地系统内部供氧能力,提高湿地系统的除氮能力     

不同浓度臭氧对循环水养殖系统生物膜活性及其净化效能的影响

本文通过在循环水养殖系统中添加不同浓度的臭氧,研究其对循环水养殖系统生物膜活性及其净化效能的影响.结果显示,当氧化还原电位(ORP)小于450 mV时,氨氮的去除率随着臭氧浓度升高而升高,最高去除率达39.9％,亚硝酸盐氮的平均去除率为28.2％,生物膜菌群的平均存活率为88.1％,生物膜对养殖水体氨氮和亚硝酸盐氮的处理效果良好;当氧化还原电位为500 mV时,经过臭氧24 h处理,氨氮和亚硝酸盐氮的去除率分别由36.5％、28.1％降到12.2％、8.4％,而臭氧4h处理后,生物膜对氨氮和亚硝酸盐氮的去除率分别由47.5％、32.1％降到5.0％、3.3％,水处理效果明显下降,生物膜菌群存活率由88.1％降到31.5％.由此可见臭氧添加浓度对生物膜及净化效能有重大影响.综合试验结果和分析评估,建议封闭循环水养殖系统的臭氧添加量以控制生物滤池内的氧化还原电位低于400 mV为宜,可保证循环水系统的安全性和经济性.     

Application of sediment microbial fuel cell for in situ reclamation of aquaculture pond water quality

Performance of sediment microbial fuel cell (SMFC) with external resistance (SMFC-1) as well as short-circuited mode (SMFC-2) was evaluated at different operating temperatures (28–30 °C and 21–25 °C) and in presence and absence of aeration at the cathode. The performance was evaluated in terms of chemical oxygen demand (COD) removal and total kjeldahl nitrogen (TKN) removal for offering in situ treatment of aquaculture pond water. SMFC-2 demonstrated maximum COD and TKN removal efficiencies both in the absence and presence of aeration near cathode as compared to SMFC-1. With aeration at cathode, the COD and TKN removal efficiencies were 79.4% and 92.6% in SMFC-1 and 84.4% and 95.3% in SMFC-2, respectively. Without aeration and at lower operating temperature, the COD and TKN removals were slightly lower, yet satisfying aquaculture quality norms. SMFCs demonstrated effective in situ remediation of aquaculture water and can drastically save the operating cost of aquaculture.     

The possibility of application of agglomerate elastomers (EPP) as media for biological bed in aquaculture

The aim of the study was to determine the possibility of experimental media (agglomerate elastomers EPP) application as biological media bed, which serves the purpose of water purification in recirculating aquaculture systems (RAS). RAS enables mass‐production of fish in small volume of water in a limited area. This involves the possibility of multiple usage of water during culture. However, for that purpose of maintaining proper physico‐chemical parameters, water purification from products of metabolism, especially toxic nitrogen compounds, is required. One of the simplest and most effective ways to achieve it is combining application of two types of water filtration: mechanical and biological. It is needed to study new media for biological bed with proper filling is able to purify water from toxic nitrogen compounds.     

序批式生物膜法处理水产养殖废水的研究

目前我国水产养殖废水直接排放的现象较多, 使受纳水体富营养化和生物多样性降低; 同时养殖水体中残饵、水生生物排泄物容易引起水体溶解氧下降、病原体增加并产生有害物质如氨氮、亚硝酸盐等, 引起养殖对象发病甚至死亡。提出采用以组合填料为载体的序批式生物膜反应器处理水产养殖废水。通过试验确定了最佳运行模式: 水力停留时间12 h, 其中瞬时进水y 厌氧( 3 h) y 曝气( 5 h) y 添加原水(添加比1B 3) y 缺氧( 3 h) y 曝气( 1 h) y 沉淀( 0. 5 h) y 排水( 0. 5 h), 并考察了试验对污染物的去除特性。试验结果表明了序批式生物膜法处理水产养殖废水的可行性, 对有机物、氨氮、TN、TP的平均去除率分别为91. 1%、85. 1%、751 8%、89. 5%, 处理后出水可回用于水产养殖。