• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.125-125
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• 2003

Recirculating aquaculture systems consist of different treatment compartments that maintain water quality within the ranges of commonly recommended for fish culture. This paper presents the common considerations in designing different treatment compartments as well as the engineering criteria in designing closed recirculating aquaculture system including a circular tank for fish culture, a sedimentation basin and a foam fractionator for solids removal, two styrofoam bead filters for TAN removal, a sand filter for nitrate removal, and aerators. The main purpose is to outline a common procedure in designing of closed recirculating aquaculture system for marine fish culture.

• Journal of Power System Engineering
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• v.9 no.1
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• pp.36-41
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• 2005

This study investigated the performance of a vortex hydrocyclone for solid removal in a recirculating aquaculture system. In a fish-breeding industry, effluent water is mainly disposed by gravity sedimentation. Thus, a large settling tank and a lot of water are needed to purify effluent water. However, this typical method does not show consistent efficiency. In case of low efficiency, discharged water contains a lot of feeding sediments. This causes environmental problems. Instead of this typical method a hydrocylone is tested to discharge water which contains a lot of feeding sediments. In this paper, a hydrocyclone with low velocity and pressure drop in a recirculating aquaculture system is investigated.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.219-220
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• 2003

The success of recirculating system depends largely on the treatment efficiency of waste generated in the system. fine solids were suspected to be responsible for fish kill in a recirculating system. Clogging of biofilter may be induced by high solids concentration in recirculating systems. Also, the solids could generate more ammonia nitrogen and oxygen demand if not removed out of recirculating system as soon as possible (Weeks et al., 1992). (omitted)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.2
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• pp.73-78
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• 2007

The suitability of a flexible fiber filter for removing suspended solid (SS) in a recirculating aquaculture system was evaluated. This study focused on variation in the performance with a change in filtering time, influent water quality, and filtering mode duration. The particle distribution diagram of the filter effluent showed that the number of particles bigger than $5-8{\mu}m$ decreased dramatically, and the removal efficiency exceeded 80%. Although the removal efficiencies of SS and chemical oxygen demand (COD) were dependent on the quality of the influent, the SS and COD concentrations of the effluent were not affected by the influent concentrations. This was despite the deterioration if water quality after feeding in the rearing tank. The performance of the filter was not affected by the filtering mode duration, feeding conditions, or filtering time. The SS concentration and turbidity of the recirculating-type rearing tank were 30% and 50% lower, respectively, than of the a non-recirculating-type rearing tank under the same operating conditions. The flexible fiber filter was applicable to a recirculating aquaculture system that uses plenty of seawater, based on its low filtering resistance $(2kg_f/cm^2)$, high flux $(330m^3/m^2/hr)$, and high fine particle removal efficiency (80%, $5-8{\mu}m$).

• Journal of Marine Bioscience and Biotechnology
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• v.4 no.1
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• pp.1-5
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• 2010

With the world's population increase, demands of fish production increased rapidly. Because of the demand increase, methods of aquaculture also become more intense. With the increasing intensity of aquaculture, more metabolites in the system are accumulated. The metabolites accumulated in the system turn to the causatives of water quality deterioration and become limiting factors for fish growth. Due to the toxicity of ammonia, ammonia removal is needed in aquaculture system. Biofilters, often referred as biological filter or nitrification filter are commonly used in recirculating aquaculture system to remove ammonia and convert it to nitrite, and then to nitrate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.343-350
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• 2016

The sea cucumber Apostichopus japonicus is a commercially valuable aquaculture species in Korea. Aquaculture species require specific nursery culture conditions to increase survival and growth rates. Sea cucumbers hibernate during the high temperatures of summer and during the low temperatures of winter, and suboptimal temperature conditions decrease sea cucumber growth and survival rates. The natural South Korean environment is very unfavorable for culturing sea cucumber; therefore, developing a recirculating aquaculture system (RAS) capable of breeding and growing sea cucumber year-round is necessary. The aim of this study was to investigate growth performance of juvenile sea cucumber in a RAS. Growth and survival rates of juvenile sea cucumber were high during our 24-week experiment. Sea cucumber survival rates were 87.8-93.3%, and specific growth rates were 0.4689-0.7846.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.70-76
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• 2001

An integrated recirculating aquaculture system suitable to our country's situation was designes and developed, The integrated recirculating aquaculture system consisting of a double drain type rearing tank of the $2.5 m^3$, a sedimentation tank for removal of settleable solids, a floating bead filter for the removal of suspended solids, a foam separator for removal of fine particles and a rotating biological contactor for the nitrification was designed and manufactured. The integrated recirculating aquaculture system was stocked with nile tilapia (Oreochromis niloticus) at $2\%$ rearing density for 2 weeks. Feed coefficient was 1.4 and average daily growth rate was $0.64\%$ in the system for 2 weeks.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.1
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• pp.87-99
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• 2024

This study deals with the application of an artificial neural network (ANN) model to predict power consumption for utilizing seawater source heat pumps of recirculating aquaculture system. An integrated dynamic simulation model was constructed using the TRNSYS program to obtain input and output data for the ANN model to predict the power consumption of the recirculating aquaculture system with a heat pump system. Data obtained from the TRNSYS program were analyzed using linear regression, and converted into optimal data necessary for the ANN model through normalization. To optimize the ANN-based power consumption prediction model, the hyper parameters of ANN were determined using the Bayesian optimization. ANN simulation results showed that ANN models with optimized hyper parameters exhibited acceptably high predictive accuracy conforming to ASHRAE standards.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.11
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• pp.3083-3098
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• 2023

As demands for efficient and echo-friendly production of marine products increase, smart aquaculture based on information and communication technology (ICT) has become a promising trend. The smart aquaculture is expected to control fundamental farm environment variables including water temperature and dissolved oxygen (DO) levels with less human intervention. A recirculating aquaculture system (RAS) is required for the smart aquaculture which utilizes a purification tank to reuse water drained from the water tank while blocking the external environment. Elaborate water treatment should be considered to properly operate RAS. However, analyzing the water treatment performance is a challenging issue because fish farm circumstance continuously changes and recursively affects water fluidity. To handle this issue, we introduce computational fluid dynamics (CFD) aided water treatment analysis including water fluidity and the solid particles removal efficiency. We adopt RAS parameters widely used in the real aquaculture field to better reflect the real situation. The simulation results provide several indicators for users to check performance metrics when planning to select appropriate RAS without actually using it which costs a lot to operate.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.174-176
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• 2019

A novel bacterium, designated strain RR4-38 (= KCTC 52651 = DSM 108068), belonging to the family Flavobacteriaceae was isolated from a biofilter in the seawater recirculating aquaculture system in South Korea. A single complete genome contig which is 3,182,272 bp with 41.9% G+C content was generated using PacBio RS II platform. The genome includes 2,829 protein-coding genes, 6 rRNA genes, 38 tRNA genes, 4 non-coding RNA genes, and 9 pseudogenes. The results will provide insights for understanding microbial activity in the seawater recirculating aquaculture system.