池塘封闭循环水养殖废水脱氮的试验研究

确定封闭循环水养殖池塘系统对养殖水体的脱氮能力.循环净水系统主要有生物合成固氮、污泥吸附分离脱氮、光化学脱氮、微生物脱氮、物理脱氮等环节,采用海洋监测国家标准方法对系统中的南美白对虾(Penaeus vannamei)养殖水体进行跟踪监测.结果表明:系统对养殖水体中硝酸盐氮、亚硝酸盐氮和氨氮的去除率分别为10.37%～27.35%、22.45%～44.74%和22.00%～79.53%,脱氮解毒效果较好.     

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.     

生物海绵铁复合填料曝气生物滤器处理养殖海水脱氮条件优化研究

为了提高海水循环养殖系统(RAS)中曝气生物滤器(BAF)系统脱氮效率,减少亚硝态氮(NO^2--N)积累和曝气量,将铁基复合生物填料引入BAF系统,以间歇式曝气营造BAF系统好氧、缺氧和厌氧的循环环境,采用扫描电子显微镜考察了填料表面形态,研究了不同复合填料配比及曝气运行方式下的氮污染物的处理效果,并利用单因素实验对生物滤器的各重要运行参数进行优化。结果显示,添加铁基填料可以提高约10%的脱氮效率,降低25%的NO^2--N积累并节省50%的曝气量;海水BAF系统在如下运行参数条件下有更优的去除性能,间歇曝气时长为12 h,聚碳酸亚丙酯(PPC)凝胶亲水填料与海绵铁复合配比为3∶1,温度为30℃,水力负荷率(HLR)为1.2 m^3/(m^2·d),进水氨氮(NH4^+-N)负荷为1 mg/L。研究表明,在RAS中引入铁基填料并以间歇曝气方式运行,能提高BAF系统处理氮污染物效率,明显降低NO^2--N积累和运行耗电量,为BAF在RAS中的生产应用提供理论依据。     

封闭流水式网箱养殖混合供电系统设计

封闭流水式网箱养殖优点是零排放无污染,符合环保养殖要求,缺点是水质容易恶化,水交换与排污能耗大。为了降低能耗并确保设备正常运行,研发太阳能-市电-柴油发电机混合供电系统。基于蓄电池充放电特性,采用最大功率点跟踪(MPPT)和数字信号处理(DSP)技术实现太阳能智能充放电控制与保护,应用双电源自动转换开关技术实现有序混合供电。太阳能月均发电量250 k W·h,日均供电8.3 k W·h,满足负载日均耗电6.6~8.8 k W·h要求。结果表明,在阳光充足情况下,以太阳能供电为主;当出现连续阴雨天气情况下,供电顺序为蓄电池(充满状态可放电3~4 h)、市电、柴油发电机。随着太阳能系统性价比的提高,节能效果将更加明显。     

Chemical addition for accelerated biological filter acclimation in closed blue crab shedding systems

Heavy loading of commercial crab shedding systems is a major problem at the beginning of the softshell crab season if the biological filters are not properly acclimated. Thus methods that can be used to accelerate filter acclimation in a commercial setting are desirable. Experimental shedding systems with submerged rock filters impacted by media size, commercial additives containing nitrifying bacteria, and chemical addition were examined. Filters acclimated with crabs took 35 days to adjust to base line water quality conditions. The filters demonstrated the ability to be increased to full design loading if acclimated with 25% of the shedding system design. Filter media size and addition of concentrated nitrifying bacteria did not have any significant effect on acclimation time of the nitrification beds. Addition of ammonia to simulate loading acclimated a biological filter without the use of animals, but did not shorten the acclimation time. The most promising avenue of research is the addition of ammonia and nitrite in combination to stimulate growth in both species of nitrifying bacteria simultaneously. Nitrite addition during startup of a biological filter reduced the acclimation period by 10 days (or 28%).     

Leaching of plastics used in closed aquaculture systems

Toxic dioctyl phthalate plasticizer leaches from new plastics used in closed aquaculture systems. Closed systems employing new plastics probably should be flushed for about 10 days with warm fresh water before they are put into use.     

生物强化移动床生物膜反应器处理水产养殖循环水初步研究

利用自制的硝化细菌菌剂促进移动床生物膜反应器(Moving bed biofilm reactor,MBBR)的挂膜启动,分析不同载体氨氮负荷、碳氮比条件下反应器运行状况,并进一步进行了实验室模拟循环水养殖草金鱼实验。结果显示,利用自制硝化菌剂能够完成整个移动床反应器的启动过程,在接种15 d后使循环出水氨氮稳定在1 mg/L以下。单位体积载体氨氮负荷实验表明,MBBR能够在100 mg TAN/(L填料·d)条件下,使出水满足一般水产养殖水质要求(氨氮0.5 mg/L,亚硝氮0.1 mg/L)。进水碳氮比在1以内时MBBR能够稳定高效运行。在实验室模拟循环水养殖过程中,经菌剂强化的MBBR能维持循环出水氨氮低于0.5 mg/L,亚硝氮低于0.05 mg/L。     

封闭流水式网箱鳗鱼养殖新技术

封闭流水式网箱鳗鱼养殖新技术是参照陆基水泥精养鳗池的原理,采用不透水帆布类材料制成封闭流水式网箱,抽取15～20 m深处水温、水质稳定的水库中下层水进行流水养殖.该养殖模式是将装备技术、水质净化技术等技术进行整合、组装和集成,从而达到健康、快速和最大限度地提高单位水体产量和质量的目的,是一种既不产生内外环境污染、基本不消耗水资源,又不占地的鳗鲡健康养殖新模式.     

工厂化水产养殖中的自动控制技术

本文从工厂化水产养殖自动控制系统的组成、自动控制方法、自动控制技术在水质参数检测与调控中的应用等方面,论述了有关研究的技术成果和未来发展趋势.根据水产养殖工业化和自动化发展,以及自动控制技术在水产养殖中的广阔应用前景,指出了发展水产养殖自动化检测和调控精准技术的必要性,提出发展规范化、标准化的水产养殖自动化技术,以推动...     

工厂化水产养殖中的自动控制技术

本文从工厂化水产养殖自动控制系统的组成、自动控制方法、自动控制技术在水质参数检测与调控中的应用等方面,论述了有关研究的技术成果和未来发展趋势。根据水产养殖工业化和自动化发展,以及自动控制技术在水产养殖中的广阔应用前景,指出了发展水产养殖自动化检测和调控精准技术的必要性,提出发展规范化、标准化的水产养殖自动化技术,以推动水产养殖工业化的发展。     

封闭循环水系统和船体网箱驯养圆口铜鱼幼鱼的效果比较

以长江野生圆口铜鱼(Coreius guichenoti)幼鱼(约150~400 g)为试验对象,开展了封闭循环水系统和船体网箱驯养圆口铜鱼的比较试验。每种驯养条件下的试验鱼均按规格分2组进行驯养。封闭循环水系统中2组试验鱼的放养密度分别为11.48 kg/m3和17.65 kg/m3,驯养时间为279 d,平均水温为(14.5±3.4)℃。船体网箱中2组试验鱼的放养密度分别为4.40 kg/m3和7.06 kg/m3,驯养时间244 d,平均水温为(20.0±3.1)℃。所有试验鱼均采用人工配合饲料进行饱食投喂。结果显示,封闭循环水系统和船体网箱驯养试验鱼的成活率分别为97.75%和83.78%,且大规格试验鱼比小规格试验鱼成活率略高。封闭循环水系统中两组试验鱼的体重特定生长率分别为0.08%/d和0.11%/d,船体网箱中两组试验鱼的体重特定生长率分别为0.17%/d和0.21%/d。船体网箱试验鱼的丰满度总体大于封闭循环水系统的试验鱼。封闭循环水系统中全年未暴发重大疾病,船体网箱中暴发过一次较大规模的小瓜虫、车轮虫等寄生虫病。结果表明,封闭循环水系统驯养圆口铜鱼的成活率高但生长较慢,船体网箱驯养圆口铜鱼的生长优势明显但易遭受疾病侵袭。综合而言,封闭循环水系统和船体网箱养殖均是当前比较可行的圆口铜鱼驯养方式。     

应用生物脱氮新技术处理循环养殖废水的研究

由于氨氮的传统去除在工艺运行上有多方面的局限性,寻求低价可靠的生物完全脱氮工艺,成为循环水养殖系统中亟待突破的关键技术,近年来迅速发展的一些生物脱氮新技术为解决这一难题提供了新的思路。综述了循环养殖废水脱氮研究现状及生物脱氮新技术,指出了将脱氮新技术应用于养殖废水处理具有的多方面的优点及存在的一些有待于研究解决的问题。     

养殖水体中孔雀石绿的快速检测技术

利用筛选柱快速检测养殖水体中孔雀石绿,发现当水样中孔雀石绿浓度为5.0 ng/mL和10.0 ng/mL时,检测过程中未发现颜色变化;当水样中孔雀石绿浓度为50.0 ng/mL或以上时,检测过程中颜色变化较明显,该结果能满足广大基层养殖户快速筛选的需求。     

Herbaceous plants as part of biological filter for aquaponics system

Aquaponics is a recirculating aquaculture system (RAS), where plants and aquatic animals are grown using the same water. In these systems, plants act as part of biological filters. The cultivation of O. basilicum, Menta x piperita and M. spicata is commonly integrated to the production of O. niloticus in aquaponics. The aim of this study was to evaluate the ability of these herbs as part of biological filters for tilapia intensive production in aquaponics. Various physicochemical parameters were evaluated as water quality indicators. N and P content in the different elements of the system were also measured. Results showed that for tilapia growing the three herbaceous evaluated could be used as part of the biological filters in aquaponics, because they remove significant concentration in nitrogen compounds and phosphates; however, there were no differences among species. There was a positive relationship between the time and the levels of NH₄ and therefore NO₃^? in the water. The pH, temperature and dissolved oxygen were kept at appropriate ranges for tilapia. The electrical conductivity and total dissolved solids were in suitable levels for growing herbaceous, which adapted to flooded substrates, with water constantly moving and high concentration of dissolved oxygen. A key parameter to consider is the oxygen concentration in water when herbaceous is used in aquaponics, due to the high input of this element for these species need, especially basil. Tilapia largely incorporated N and P entering the system.     

3种填料对集装箱循环水养殖废水处理的初步研究

为探讨聚丙烯塑料发泡材料(EPP)、悬浮球填料和海绵填料对集装箱循环水养殖废水中细菌吸附性能的差异,以及3种填料挂膜启动和挂膜成熟后对氨氮(NH_4~+-N)、亚硝酸盐氮(NO_2~--N)和硝酸盐氮(NO_3~--N)的净水效果,以集装箱循环水养殖废水为研究对象,采用自然挂膜的方式进行了为期3个月的试验,并对相关指标进行测定。结果显示:EPP填料对养殖废水中细菌的吸附能力最好,另外两种填料对细菌的吸附能力次之并且差异不显著(P0.05);3种填料自然挂膜成熟的时间分别为21 d、26 d和30 d;各填料挂膜成熟后处理高浓度NH_4~+-N养殖废水时,NH_4~+-N浓度与NO_2~--N浓度之间的关系可以用多项式y=ax~2+bx+c进行拟合,NH_4~+-N浓度与NO_3~--N浓度之间的关系可以用对数式y=aln(x)+b进行拟合。研究表明:EPP填料、悬浮球填料和海绵填料均可作为生物填料用于集装箱循环水养殖系统。     

Rate models for a marine biological filter

An empirically based model is proposed for the kinetics of oxidation of ammonia and nitrite in a marine biological filter at low concentration. Assuming first order kinetics, the rate constants for Nitrosomonas and Nitrobacter respectively are correlated as functions of pH, temperature and dissolved oxygen. A series of experiments using a recirculating batch biological filter was conducted to validate the model over a limited range of conditions. Predictions of the model agree satisfactorily with literature values of the rate constants and show favourable comparison with the observed experimental data.     

闭合循环水产养殖-植物水栽培综合生产系统的工艺设计及运行效果

闭合循环水产养殖-植物水栽培综合生产系统主要由鱼类养殖池、蔬菜和花卉水培渠、循环水处理系统构成,是一种新型"养殖-种植-水质净化"生产模式。在上海市青浦区的实践表明:①单位水体红罗非鱼(Tilapiamossambica(♀)×Tilapianilotica(♂))和暗纹东方(Fuguobscurus)的产量分别达到58kg·m-3和12.28kg·m-3,养殖期间,氨氮浓度<1.5mg·L-1,亚硝氮浓度<0.8mg·L-1,DO>5.0mg·L-1;②水栽培蔬菜生长良好,对氨氮、亚硝氮、硝氮、总氮、磷酸盐和COD的最大去除率分别为57.46%、51.72%、3.7%、10.67%、9.72%和21.78%,水培蔬菜渠进水和出水的平均N/P分别为6.60∶1和6.53∶1;③生物过滤器对流经水体的NH 4 N、NO-2 N、COD一次性去除率分别为44.79%、20.31%、20.10%;④泡沫分离—臭氧消毒装置对养殖水体中异养细菌的去除率为93.58%,NH 4 N、NO-2 N的去除率为39.00%、38.10%,能明显提高水体中的pH和DO。     

Performance of sequencing microbead biofilters in a recirculating aquaculture system

Biological filtration, or biofiltration, is the key technology in recirculating aquaculture systems. Sequencing microbead biofilters, in which the media maintains a continuous up-and-down movement, are based on traditional microbead filters but offer superior filtration properties. The performance characteristics of a sequencing microbead biofilter installed in a recirculating aquaculture system for rearing Barcoo perch at 29 ± 1 °C were examined. The total ammonia-nitrogen (TAN) concentrations and the nitrite-nitrogen concentrations during a 52-day culture period were maintained blow 1.6 mg/L and 0.9 mg/L. In order to ensure efficient biofiltration, the optimal actual application of hydraulic retention time was determined to be approximately 3–5 min. The water flow produced by the reciprocating motion of the media served to wash away suspended solids, ensuring the occurrence of optimal nitrification processes. Additionally, the reciprocating motion of the media enhanced ammonia treatment efficiency significantly by improving the transport of nutrients and nitrification activity. Compared to a static situation the ammonia removal rate increased by 27% based on the application of up-and-down reciprocating movement. The biofilm on the microbead forms as a compact, complex, and homogeneous structure, consisting of numerous microscopic thin sheets. Additionally, a multitude of pores, interstitial voids, and vertical channels were widely observed to convey obviously advantageous properties in support of fluid passage, thus enhancing mass transfer and ultimately contributing to biofiltration effectiveness. The optimum biofilm thickness for providing efficient biofiltration was determined to be approximately 70 μm for this filter.     

Management of a closed brackish water system for high-density fish culture by biological and chemical water treatment

During a 1-year operation of a warm water recycling system (salinity about 8‰) sufficient water quality was maintained under high stocking density conditions using Tilapia and the European eel as potential candidates for intensive farming. The final fish: water ratio was 1 : 23 (or 43.5 g fish per 1 water) for the whole experimental culture unit. The total water volume of the system was about 5 m³. The water treatment unit held 52% of the total volume, whereby 46% was available for fish culture. Combined biological (trickling filter with Hydropack-foil) and chemical (ozonation) water treatment proved to be useful to meet water quality requirements under these rearing conditions. After an initial conditioning period of the biofilter, BOD varied from 4.5 to 6.0 mg O₂/l, ammonium levels were maintained at less than 1 mg/l and nitrite concentrations averaged 1 mg/l. The average efficiency (oxidation rate) of the biofilter for NH₄⁺-and NO₂^?-oxidation was 31% and 13.2%, respectively. The pH was stabilized slightly above 7.0 when a denitrification unit was connected to the system. Nitrate concentration of the system levelled of between 200 and 400 mg/l and was regulated by the addition of an electron donator (first glucose solution, then methanol) to the denitrification unit; the elimination rate averaged 50% with a maximum of 98%. High nitrite levels were avoided by ozone treatment of the recycled water. The accumulation of low-biodegradable substances was also successfully counteracted by ozonation. Fish growth rates of about 30% per month at high stocking densiteis were reached for Tilapia at a fish: water ratio of 1 : 4.6 (217 g fish per 1 water), indicating that a combination of biological water treatment and ozonation supports intensive fish culture in a closed aquaculture system.