When Aquaculture Wastewater Needs a More Practical Treatment Solution

Aquaculture wastewater requires effective management because daily farming activities continuously introduce organic matter, suspended solids, nutrients, and other substances into the water. Feeding, fish metabolism, cleaning, and water exchange can all affect wastewater characteristics.

For an aquaculture farm, the treatment system needs to handle changing wastewater flow and pollutant concentrations while fitting within the available site area. Selecting the right treatment vessel is therefore an important part of the overall system design.

In Sichuan, an aquaculture wastewater project required vertical treatment vessels that could support the treatment process while making efficient use of limited land. The project ultimately used two vertical carbon steel vessels with different diameters and the same height.

The selected equipment included a Φ6×16.5m tank and a Φ7.6×16.5m tank. Their different diameters allowed the two vessels to serve different stages of the treatment process, while the 16.5-meter height provided a practical vertical configuration for the project site.

Aquaculture Wastewater After Feeding Cycles

Aquaculture wastewater characteristics can change throughout the production cycle. Feeding activity introduces organic substances into the water, while fish metabolism contributes nitrogen-containing compounds.

Ammonia nitrogen is one of the important parameters considered in aquaculture wastewater treatment. Its concentration can vary according to feeding levels, stocking density, water exchange, and biological treatment conditions.

Suspended solids and sludge can also accumulate in treatment systems. Effective process design needs to provide suitable space and equipment configuration for wastewater treatment, solids separation, circulation, and subsequent discharge.

This means the treatment vessel should not simply be considered as a storage tank. Its dimensions, internal structure, material, connections, and installation arrangement should correspond to the wastewater treatment process.

For fish farms operating in areas where land availability is limited, vertical treatment vessels can provide another equipment arrangement compared with large horizontal tanks.

Making Better Use of Limited Land with Vertical Treatment Vessels

A vertical treatment vessel uses the available height of a site to provide the required working volume.

Compared with a horizontally arranged tank with the same approximate capacity, a vertical vessel can occupy a smaller footprint. This can be useful for aquaculture farms where the treatment area must coexist with ponds, production facilities, access roads, equipment rooms, and other farm infrastructure.

The Sichuan project used two tall vertical vessels, each with a height of 16.5 meters. The Φ6×16.5m tank and Φ7.6×16.5m tank were designed as part of the wastewater treatment system.

The vertical arrangement also provides a clear equipment structure. Different treatment stages can be assigned to individual vessels, allowing the process flow to be organized from pretreatment through subsequent treatment or polishing.

The final arrangement depends on wastewater characteristics, required treatment capacity, site conditions, and the process selected by the engineering team.

A Sichuan Aquaculture Wastewater Project

The project was located at a Sichuan aquaculture farm and focused on wastewater treatment using vertical carbon steel vessels.

For this project, we supplied two vertical tanks:

lΦ6×16.5m vertical carbon steel tank

lΦ7.6×16.5m vertical carbon steel tank

The two vessels had different diameters but the same 16.5-meter height. This configuration was selected to provide different working volumes while maintaining a consistent vertical equipment concept.

The two tanks were assigned to different stages of the wastewater treatment process. One vessel was used for pretreatment, while the other supported the subsequent polishing stage.

Using two vessels instead of treating the complete process as one single tank provided greater flexibility for process organization. Each vessel could be designed around its specific process function, flow characteristics, and required treatment stage.

Why Were Two Different Tank Diameters Used?

The different diameters were directly related to the different process requirements of the two vessels.

The Φ6×16.5m tank and Φ7.6×16.5m tank have the same height but different diameters, which means they provide different internal volumes.

The smaller-diameter vessel can be assigned to a treatment stage requiring a relatively lower working volume, while the larger vessel can provide additional volume for a process stage requiring greater capacity.

In this project, one vessel served the pretreatment stage and the other supported the polishing stage.

This approach allows the treatment system to be divided into functional sections instead of using one vessel for all process steps. It also gives engineers greater flexibility when arranging inlet and outlet connections, process equipment, inspection access, and supporting systems.

The 16.5-meter height also creates a consistent vertical equipment layout, which can help optimize the available land area.

Vertical Carbon Steel Tanks for Aquaculture Wastewater Treatment

Material selection is an important part of wastewater treatment vessel design. For the Sichuan project, carbon steel was selected as the main tank material together with an appropriate anti-corrosion system.

Carbon steel is widely used for industrial tanks because it provides a practical combination of mechanical strength, fabrication flexibility, and cost efficiency.

For wastewater applications, carbon steel surfaces require appropriate corrosion protection. The coating system can be selected according to the wastewater characteristics, operating environment, tank design, and project requirements.

Compared with stainless steel, carbon steel can provide a more economical option for large-volume industrial vessels when combined with a suitable protective coating.

FRP is another material used in some wastewater applications. However, the final material choice should be based on tank dimensions, structural requirements, installation conditions, process medium, temperature, design standards, and project budget.

For large vertical vessels, material selection should therefore be considered together with structural design and fabrication requirements rather than evaluated only by material price.

Designed for Sichuan Site Conditions

The equipment design for an aquaculture wastewater project needs to consider the actual installation environment.

The Sichuan project required vertical cylindrical tanks suitable for the local site conditions. The tanks were designed according to the applicable national vertical cylindrical tank standard and adapted to the project's environmental and structural requirements.

Local humidity was considered when determining the anti-corrosion approach. Soil conditions were also taken into account because foundation design and equipment installation are closely related to site conditions.

The project site was also located within a seismic zone, so the tank structure and supporting design needed to correspond to the applicable seismic requirements.

These factors demonstrate why an industrial wastewater vessel should be designed according to its actual location rather than using an identical configuration for every project.

A tank manufacturer needs to consider the equipment itself together with foundation conditions, site environment, applicable standards, installation method, and local engineering requirements.

Our Quality Control Process

For a large carbon steel treatment vessel, manufacturing quality depends on controlled production at every stage.

At Center Enamel, quality control can begin with incoming material inspection. Materials and components are checked against the approved specifications before fabrication.

The next stage is welding. Welding procedures and fabrication requirements are followed according to the approved engineering documentation.

After welding, appropriate non-destructive testing can be performed to verify the quality of selected welded joints. The inspection scope depends on the project specifications and applicable standards.

Hydrostatic testing is another important quality-control stage for suitable tank structures. It allows the fabricated vessel to be checked under the specified test conditions before delivery.

After testing and inspection, the carbon steel surface receives the specified anti-corrosion coating system. Surface preparation and coating application are controlled according to the project requirements.

Finally, the completed equipment is prepared for transportation. Packing and protection procedures are arranged according to the tank dimensions, components, and delivery requirements.

This sequence creates a clear quality gate:

lIncoming inspection

lWelding and fabrication

lNDT inspection

lHydrostatic testing

lSurface preparation and coating

lFinal inspection and packing

Such a process provides customers with a traceable manufacturing workflow from raw material inspection to finished equipment delivery.

Engineering and Project Support

Supplying a wastewater treatment vessel involves more than manufacturing the tank itself.

For customized projects, Center Enamel can provide engineering drawings and equipment documentation according to project requirements. These documents can support foundation preparation, equipment installation, process connection, and project coordination.

Installation guidance can also be provided to help customers and local installation teams understand the equipment structure and installation sequence.

For long-term operation, spare parts and after-sales support can also be arranged according to the equipment configuration and project requirements.

Warranty terms are provided according to the specific project agreement.

This project-oriented approach allows the equipment supplier to remain involved beyond fabrication and shipment, supporting customers through the installation and application stages.

How to Select a Tank for Aquaculture Wastewater Treatment

The correct vessel size should be determined from actual wastewater data and process requirements.

Flow Rate

The daily and peak wastewater flow rate is one of the first parameters required for equipment sizing. Seasonal production changes should also be considered where applicable.

Wastewater Characteristics

Important information may include ammonia nitrogen, suspended solids, organic load, pH, temperature, salinity, and other parameters relevant to the treatment process.

Treatment Requirements

The required treatment stages and final discharge limits determine the role and working volume of each vessel.

Site Dimensions

Available land area, foundation location, building height, access roads, and equipment installation routes should be considered before finalizing the tank dimensions.

Applicable Standards

The customer should identify the required national, regional, or project-specific tank design standards. The manufacturer can then develop the equipment according to the applicable requirements.

Three Things to Prepare Before Requesting a Quote

To obtain a more accurate quotation for an aquaculture wastewater treatment vessel, customers should prepare several basic project details.

First, provide available water quality and wastewater data. Flow rate, wastewater composition, operating temperature, and required discharge parameters can help the manufacturer understand the treatment conditions.

Second, provide the available site dimensions. Information about the installation area, available height, foundation conditions, and equipment access can help determine whether a vertical configuration is appropriate.

Third, provide the required design and manufacturing standards. Different projects may have different technical specifications, documentation requirements, inspection requirements, and coating standards.

With these details, the manufacturer can develop a more suitable preliminary tank configuration instead of providing a generic vessel quotation.

Project Specifications at a Glance

lProject: Sichuan Aquaculture Wastewater Project

lApplication: Aquaculture wastewater treatment

lLocation: Sichuan, China

lEquipment: Vertical carbon steel treatment vessels

lQuantity: 2 tanks

lTank 1: Φ6×16.5m

lTank 2: Φ7.6×16.5m

lTank Height: 16.5m

lMaterial: Carbon steel

lSurface Protection: Anti-corrosion coating

lProcess Arrangement: Pretreatment and polishing

lDesign Approach: Vertical cylindrical tank configuration

lStandard: Applicable national vertical cylindrical tank standard

lSite Considerations: Local humidity, soft soil conditions, and seismic requirements

Why Choose Center Enamel for Vertical Treatment Vessels?

As an industrial process equipment manufacturer, Center Enamel provides customized vessel solutions for wastewater treatment and other industrial applications.

For aquaculture wastewater treatment projects, our engineering team can develop vertical carbon steel tanks according to flow rate, working volume, process requirements, installation space, material requirements, and applicable standards.

The Sichuan project demonstrates how different tank diameters can be combined within one treatment system. The Φ6×16.5m and Φ7.6×16.5m vessels provided different working volumes while maintaining a vertical arrangement suited to the available site.

From material inspection and welding to NDT, hydrostatic testing, coating, and packing, the manufacturing process is organized around defined quality-control stages.

Center Enamel can also provide drawings, installation guidance, spare parts, warranty support, and project-specific technical documentation.

For customers planning a fish farm effluent treatment project, the first step is to provide the wastewater flow rate, water quality information, available site dimensions, discharge requirements, and applicable standards. Based on these details, the appropriate vertical treatment vessel configuration can be developed.

From Aquaculture Wastewater Data to the Right Tank

The Sichuan aquaculture wastewater project used two vertical carbon steel vessels, a Φ6×16.5m tank and a Φ7.6×16.5m tank, to support different stages of the treatment process.

The project combined vertical equipment design, carbon steel construction, anti-corrosion protection, and site-specific engineering considerations. The different tank diameters provided different working volumes, while the 16.5-meter height supported efficient use of the available land area.

For aquaculture wastewater treatment, there is no single tank configuration suitable for every farm. Flow rate, wastewater characteristics, discharge requirements, site dimensions, soil conditions, environmental conditions, and applicable standards all influence the final design.

Center Enamel provides customized vertical treatment vessels based on these project parameters. If you are planning a fish farm effluent treatment system, providing your wastewater data and site information can help our engineering team develop a suitable tank solution.