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随着人口与经济的发展,水产养殖业在世界范围内迅速兴起,集约型工厂化循环水养殖因其高密度、低污染、高效率等独特的优势,契合水产养殖业绿色发展理念,已成为水产养殖转型升级的重要方向之一。水作为循环水养殖系统中重要的环境因子,其流态能够直接影响鱼类的生长及福利,同样,鱼类存在及运动也会影响到系统流态的构建。本文综合分析了循环水养殖系统中流场条件对不同鱼类生长发育及福利的影响,鱼类及其运动行为对养殖池内水动力条件及性能的影响,以及鱼类对养殖池内流场流态、水体混合等的影响。将研究鱼类运动对流场特性的影响方法主要归纳为实测法和数值研究,通过对比分析2种方法的优点和不足之处,并结合当前循环水养殖产业系统构建中的问题提出针对性方法建议,旨在为系统中水动力条件的设计拓展思路,促进循环水养殖产业流态构建向“鱼”与“水”兼顾的方向发展。 相似文献
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我国鲆鲽类循环水养殖系统的研制和运行现状 总被引：3，自引：0，他引：3
全封闭式海水循环养殖系统,是当前国际上先进养殖模式的代表,也是未来养殖产业发展的重要方向,备受世界关注。我国最早走上工厂化养殖道路的海水鱼类是鲆鲽类,现正由开放式向封闭式循环水养殖方向迈进,目前各项技术与工艺已经取得了长足进步。但是,根据对国内循环水系统装备的研制及其运行情况的跟踪调查,发现循环水处理的核心部分存在着稳定性、可靠性、经济性等问题急待研究解决。本文在分析循环系统主要配套装备和工艺参数的基础上,结合几家典型养殖企业的运行特点进行了分类剖析,针对现有装备和系统中发现的几个关键问题,提出了改进、提高的对策,可为今后鲆鲽类全循环养殖系统的升级、定型和走向国产化提供借鉴。 相似文献
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工业化循环水福利养殖关键技术与智能装备的研究 总被引：3，自引：1，他引：2
基于水产福利养殖的理念,结合封闭循环水系统养殖环境可控性高的突出特点,倡导构建适合中国国情的工业化循环水福利养殖产业模式,已成为推动我国现代渔业可持续发展的战略需求。为此,本综述从工厂化循环水鱼类养殖福利影响因子分析、集约化养殖鱼类的福利需求、工厂化循环水模式下水产福利养殖的科学评价标准制定等方面入手,开展了封闭循环水系统实施福利养殖的关键技术与智能装备集成的研究,为今后规范我国水产工业化福利养殖的生产过程管控,建立水产福利养殖保障机制,真正提高水产品质量与安全水平提供理论和技术依据。 相似文献
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过滤器和工厂化循环水养殖 总被引：1，自引：0，他引：1
过滤器是工厂化循环水养殖和水族馆养殖的核心部分，对水质状况和鱼类健康起着至关重要的作用。在一个典型的循环水水处理系统中，通常需要使用三种类型的过滤器：机械滤器、化学滤器和生物滤器。每一类型均有不同的设计，使用不同的过滤介质，以适应不同的需要。 相似文献
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A sustainable aquaculture production involves alternatives, as recirculating aquaculture systems (RAS), in order to increase the water supply efficiency. This paper aims: a) to propose a method for dimensioning a RAS filled and additionally supplied with water from a rainwater harvesting systems (RHS) and; b) to evaluate the efficiency of the system based on the supply of rainwater from the RHS, the quality of water in the RAS, and the development of aquatic organisms. A pilot aquaculture farm for rainbow trout (Oncorhynchus mykiss) production was designed and dimensioned. On one hand, the RAS with a configuration based on a treatment tower provided acceptable values of pH, TAN, and alkalinity. The temperature was slightly above the recommended temperature but did not negatively impact trout development. On the other hand, the water use efficiency reached 178 L/kg of fish, instead of 210,000 L/kg in an open flow system for trout rearing. The RHS fulfilled the additional required water on the test period of the pilot farm and is expected to supply at least 92% on average during the useful life. Regarding the aquatic organisms’ development, the system allowed both a better Length/ weight ratio and a lesser mortality rate compared to previous studies of RAS. In contrast to other studies in the literature, the mathematical models for dimensioning the system were calculated as a function of the final biomass expected in the tank instead of the quantity of supplied feed. Therefore, this method confirmed the applicability of this alternative criterion for designing biofilters and aquaculture systems. 相似文献
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为探索绿色环保的循环水养殖模式,设计循环水鱼菜共生系统(鱼菜组)、紫外灯鱼菜共生系统(鱼菜紫外灯组)及循环水养殖系统(循环水组),比较三种不同处理方式对镜鲤(Cyprinuscarpio var.specularis)、叶用莴苣(Lactuca sativa var.ramosa)生长和养殖水质的影响。结果显示,鱼菜组、鱼菜紫外灯组处理对镜鲤的生长无显著影响,但会显著影响镜鲤形态学指标,鱼菜组镜鲤肠体比显著低于循环水组。体成分方面,鱼菜组全鱼粗蛋白、粗脂肪显著高于循环水组,鱼菜组肝脏粗蛋白显著低于循环水组。鱼菜紫外灯组的细菌总数显著低于鱼菜组。水质方面,鱼菜组、鱼菜紫外灯组可显著降低系统中氨氮、硝酸盐氮及总磷总氮含量,鱼菜紫外灯组硝酸盐氮、总磷及总氮含量显著高于鱼菜组。综上所述,循环水系统耦合水培蔬菜单元可改善系统水质,改善鱼体成分,并且结合紫外灯处理可降低水体细菌总数。 相似文献
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为比较越冬期循环水系统(RAS)与生物絮团系统(BFT)两种模式下大规格罗非鱼(Oreochromis niloticus)鱼种的生长性能与养殖水质的差异。选择RAS组与BFT组,进行为期67 d的养殖,测定养殖过程中罗非鱼种的生长情况以及水质的变化情况。结果显示,RAS组与BFT组增重率和特定增长率分别为(870.69±33.25)%、(3.39±0.05)%/d和(659.47±62.84)%、(3.02±0.13)%/d,RAS组显著高于BFT组;在水质控制方面,RAS组氨氮和亚硝酸盐从养殖初期到实验结束均维持在较低水平,而BFT组在初期氨氮和亚硝酸盐有升高的趋势,峰值分别达到了(4.53±0.72)mg/L和(6.68±1.8)mg/L,分别在第3天和第6天下降到较低水平,硝酸盐两组均呈现不断积累的趋势。结果表明,RAS系统养殖罗非鱼生长速度要高于BFT系统,RAS系统在水质控制方面略优于BFT系统。 相似文献
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Ilan Halachmi Yitzchak Simon Rami Guetta Eric M. Hallerman 《Aquacultural Engineering》2005,32(3-4):443-464
The aim of this study was to develop a simulation model for finding the optimal layout and management regime for a re-circulating aquaculture system (RAS). The work plan involved: (1) quantifying the effects of fish growth and management practices on production; (2) developing a mathematical simulation model for the RAS, taking into account all factors that directly influence system profitability; and (3) estimating the production costs and, hence, the profitability of an RAS. The resulting model is process-oriented, following the flow of fish through the RAS facility, and generates an animated graphic representation of the processes through which the fish passes as it progress through the system. The simulation assesses the performance in terms of yearly turnover, stocking density, tank utilization and biomass in process, and uses statistics to track the state of the RAS and record changes that affect efficiency. The economic impact of system design and operation was modeled to enable a user to anticipate how changes in design or operating practices, costs of inputs, or price of products affect system profitability. The proposed approach overcomes difficulties in characterizing RAS design and operation. The simulation approach allows all of the RAS's components such as equipment, biological processes (e.g., fish growth), and management practices to be evaluated jointly, so that an initial design can be fine-tuned to produce an optimized system and management regime suited to a specific fish farm within a reasonable time. The methodology was executed step-by-step to design an optimal RAS that meets both economic and stocking-density limits. Optimal design specifications were presented for several case studies based on data from Kibbutz Sde Eliahu's RAS, in which Nile tilapia (Oreochromis niloticus) are raised in 20 concrete raceways. Further research should include more extensive testing and validation of the integrated model, which then should be disseminated to the aquaculture community. 相似文献
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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。 相似文献
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Recirculating aquaculture systems (RAS) discharge management limits the development of the aquaculture sector, because RAS do not automatically result in low nutrient emissions. Research has helped develop discharge management systems such as wetlands and woodchip bioreactors that have been adopted by Danish commercial model trout farms. To further develop the Danish concept, we have modelled and built a novel “zero-discharge” recirculating aquaculture system with an annual capacity of approximately 14 tonnes. The aim of this paper is to describe the entire concept and present the results from the start-up phase of the whole system. The concept includes the treatment of RAS effluent (overflow and sludge supernatant) using a hybrid solution of a woodchip bioreactor, constructed vertical wetland, and sand infiltration. Using this three-step process, the nitrate, phosphorus, and organic matter effluent are decreased to acceptable levels to reuse the water in the RAS process reducing the need for new raw water. In the first nine months of operation, a water treatment field was used as an end-of-pipe treatment to ensure the water was safe to recirculate for fish. During the winter, the water temperature dropped to 2.7 degrees in the sand filter, but the frost did not reach the water levels in any of the treatment processes. It therefore appears that a hybrid solution can operate sufficiently even in winter conditions. In the first year of operation, a woodchip bioreactor can remove 97 % of the nitrate, although the slow start-up of the RAS caused the bioreactor to be N-limited. On average, 79 % and 92 % of the inflow phosphate concentration was removed in the woodchip bioreactor and the entire hybrid treatment field respectively. The wetland and sand filter removed organic matter sufficiently (35 %), but because of the longer than designed actual water residence, it leached from the bioreactor more than was expected. Further experimentation is needed to identify the financial applicability and performance during higher feeding rates. 相似文献
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Marine recirculation aquaculture system (RAS) is a prominent technology within fish farming. However, the nitrifying bacteria in the biofilter have low growth rates, which can make the biofilter activation a long and delicate process with periods of low nitrification rates and variations in water quality. More knowledge on the microbial development in biofilters is therefore needed in order to understand the rearing conditions that favour optimal activation of the biofilters. In this case study, we investigated the activation of two biofilters in a marine RAS for Atlantic salmon post‐smolt associated with either high or low stocking densities of fish by monitoring the microbial communities and chemical composition. The results showed that the microbial communities in both biofilters were similar during the first rearing cycle, despite variations in the water quality. Nitrifying bacteria were established in both biofilters; however, the biofilter associated with low stocking density had the highest relative abundance of ammonia‐oxidizing Nitrosococcus (1.0%) and nitrite‐oxidizing Nitrospira (2.1%) at the end of the first rearing cycle, while the relative abundance of ammonia‐oxidizing Nitrosomonas (2.3%–2.9%) was similar in both biofilters. Our study showed that low fish stocking density during the first rearing cycle provided low and steady concentrations of ammonium, nitrite and organic load, which can stimulate rapid development of a nitrifying population in new marine RAS biofilters. 相似文献
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Regardless of the degree of closure of a recirculation system, effluents are produced and replacement water is needed, which limits the possibility of locating a seawater production system away from the shoreline. At the Palavas Ifremer station, in the south of France, a High Rate Algal Pond (HRAP) was operated during several years to treat the effluent from a recirculating aquaculture system before reusing it. The effect of the HRAP-treated water on the recirculation system and on the fish was investigated and the optimal algae growing conditions were defined. The experiments were carried out in three rearing systems: one flow through, one recirculating and one recirculating with a HRAP. The water flow rate, temperature, pH and salinity conditions were similar in all systems.The effect of reusing the HRAP-treated water is very limited (1) on the functioning of the recirculation system and (2) on fish performance, but it allows a significant reduction of the dissolved inorganic nitrogen and phosphorus concentration in the rearing water. HRAP treatment reduced metal accumulation in muscle and liver of RAS fish, except for chromium and arsenic. All biomarkers presented no significant difference between systems, except for Superoxide Dismutase (SOD) and EROD, which showed a higher concentration in RAS and in both recirculating system respectively. 相似文献
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Non‐specific cellular defence mechanisms of rainbow trout (Oncorhynchus mykiss) in intensive and extensive rearing technologies 
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下载免费PDF全文 Elżbieta Terech‐Majewska Patrycja Schulz Edyta Kaczorek Andrzej K Siwicki Józef Szarek Krystyna Skibniewska 《Aquaculture Research》2016,47(11):3585-3592
Water as a habitat is highly variable in terms of the physico‐chemical properties. The aim of the studies was to analyze the quality of the technology by evaluating the non‐specific cellular defence potential of rainbow trout (Oncorhynchus mykiss) in diversified intensity culture systems and in different periods of the breeding cycle. The evaluation was conducted in order to establish the scientific basis for the development of principles for recognition of the culture of this species as ‘organic’. Six rainbow trout rearing farms were selected for the studies and divided into two equal groups according to the production technology: farms with a flow through system (with single water usage – OOH) and facilities with multiple water usage via its backflow (re‐circulating system – RAS). The samples for tests were taken from 20 individuals from each fish farm. In all fish that originated both from OOH‐type farms and RAS operations, an increase in the activity of non‐specific cellular immunity in the autumn was observed. Statistically significant reduction in the activity of cellular defensive mechanisms in small (300–500 g) and big (501–850 g) fish occurred on two 3‐OOH and 3‐RAS farms in spring and autumn in 2011. During these periods, the research has shown the presence of Infectious Pancreatic Necrosis Virus (IPNV), which provoked an immune suppression. Based on the obtained results it is concluded that there were no significant differences in the parameters of non‐specific cellular immunity in rainbow trout originating from different farming systems OOH and RAS. 相似文献
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Michel Couturier Thrse Trofimencoff Jos Utge Buil Jessica Conroy 《Aquacultural Engineering》2009,41(2):71-77
The objective of this study was to determine the solids separation efficiency of the four swirl separators and the drum filter within one of the water recirculation systems (RAS) of a salmon-smolt hatchery. Water flowrates and concentrations of total suspended solids (TSS) within the RAS were measured weekly over 5 weeks in 2004 and 4 weeks in 2005. During the study, the hydraulic retention time in the tanks was 2.8 h and the feed rate ranged between 0.16 and 0.84 kg/m3 of make-up water. The system volume replacement rate and the water flow recycle rate were respectively 21%/day and 96% in 2004, and 50%/day and 91% in 2005. A mathematical model was developed to determine the transient concentration of fine particles in the recirculation loop. By fitting the predictions of the model to the measured TSS concentrations, it was determined that about 15% of the waste generated within the RAS (assumed equal to 20% of daily feed rate) was removed by the system overflow water. Using this information and TSS data from the backwash water of the drum filter, it was calculated that the swirl separators and drum filter removed respectively 63% and 22% of the waste solids rejected by the fish. 相似文献