Discover Technologies for Cleaning Wastewater in the Food & Beverage Industry

Discover the Top Technologies for Cleaning Wastewater in the Food and Beverage Industry

The food and beverage industry generates significant amounts of wastewater laden with Total Suspended Solids (TSS), Biological Oxygen Demand (BOD), and oil and grease.

Effective treatment technologies are essential to meet regulatory requirements and protect the environment.

Here, we explore the top conventional technologies used in wastewater treatment, highlighting their pros and cons in removing TSS, BOD, and oil and grease, and comparing their energy use, footprint, maintenance requirements, and costs. We also review the benefits of modified ultra-filtration, a purely mechanical approach to treating wastewater.

1. Activated Sludge Process (ASP)

The Activated Sludge Process (ASP) is a well-established and widely used method in wastewater treatment, particularly effective in reducing Total Suspended Solids (TSS) and Biological Oxygen Demand (BOD).

ASP involves aerating the wastewater to promote the growth of microorganisms that break down organic matter. This process efficiently reduces BOD, ensuring high-quality effluent. However, it requires substantial energy for aeration, resulting in high operating costs. Additionally, ASP demands a large footprint for aeration tanks and secondary clarifiers, and its maintenance is intensive, requiring regular sludge management and monitoring. The high upfront costs associated with constructing the necessary infrastructure further add to the financial burden.

Pros:

• TSS Removal: Highly effective in reducing TSS through sedimentation but is prone to upsets.
• BOD Removal: Excellent at reducing BOD due to the biological degradation of organic matter but is subject to upsets in the source water.
• Oil and Grease Removal: Moderate efficiency; requires pre-treatment to enhance effectiveness.

Cons:

• Energy Use: High energy consumption due to aeration requirements.
• Footprint: Large footprint needed for aeration tanks and secondary clarifiers.
• Maintenance: Intensive, requiring regular monitoring, chemical injection and sludge management. These systems are prone to upsets with changes in water quality.
• Costs: High upfront and operating costs due to energy demands and infrastructure needs.
• Reuse: The effluent from these systems cannot be reused in plant application such as in cooling towers, boiler make-up and irrigation.

2. Membrane Bioreactor (MBR)

Pros:

• TSS Removal: Exceptional at removing TSS due to fine membrane filtration.
• BOD Removal: Very effective, combining biological treatment with membrane filtration.
• Oil and Grease Removal: Effective when combined with pre-treatment processes.

Cons:

• Energy Use: Moderate to high, primarily due to the need for membrane aeration and pumping.
• Footprint: Smaller footprint compared to ASP due to the compact design.
• Maintenance: High maintenance required to prevent membrane fouling. Large chemical injection requirement. These systems are prone to upsets with changes in water quality.
• Costs: High initial and operating costs, mainly due to membrane replacement and energy consumption.

3. Dissolved Air Flotation (DAF)

Dissolved Air Flotation (DAF) is particularly effective in removing suspended solids and oil and grease from wastewater through a flotation process. By introducing air into the wastewater, DAF systems cause suspended particles and oils to float to the surface, where they can be easily removed. This technology is moderately energy-intensive but is more compact than ASP, making it better suited for facilities with moderate space availability. Regular maintenance is required to manage sludge and ensure the system operates efficiently. DAF systems offer a balance of moderate upfront and operating costs, making them an attractive option for many applications.

Pros:

• TSS Removal: Excellent at removing suspended solids through flotation.
• BOD Removal: Effective when used in combination with other biological treatments.
• Oil and Grease Removal: Highly effective in separating oils and greases from water when they have pre-treatment.
• Reuse: The effluent from these systems cannot be reused in plant application such as in cooling towers, boiler make-up and irrigation.

Cons:

• Energy Use: Moderate energy consumption for air saturation and recirculation pumps.
• Footprint: Moderate footprint; relatively compact compared to ASP.
• Maintenance: Regular maintenance required to manage sludge and ensure efficient operation. These systems are prone to upsets with changes in water quality.
• Costs: Moderate upfront costs with ongoing operating expenses for air and chemical usage.

4. Sequencing Batch Reactor (SBR)

Pros:

• TSS Removal: Effective, as settling occurs in the same tank used for aeration.
• BOD Removal: Excellent, due to controlled aeration cycles enhancing biological activity.
• Oil and Grease Removal: Moderate; requires pre-treatment for optimal performance.
• Reuse: The effluent from these systems cannot be reused in plant application such as in cooling towers, boiler make-up and irrigation.

Cons:

• Energy Use: Moderate to high, depending on the aeration and mixing cycles.
• Footprint: Smaller than conventional ASP due to the sequential use of a single tank.
• Maintenance: Moderate maintenance needed to manage cycle timing and sludge removal. These systems are prone to upsets with changes in water quality.
• Costs: Moderate upfront and operating costs, with savings from the reduced footprint.

Comparison of Features of Conventional Wastewater Treatment

Comparison Chart for a 400 GPM System

Formula for Capital Cost:

Total Capital Cost=GPM × 1440 × Cost per Gallon

Explanation for ASP:

To calculate the total capital cost for the ASP system, use the formula:

1. Multiply the system’s capacity in gallons per minute (GPM) by the number of minutes in a day (1440).
2. Then, multiply the result by the capital cost per gallon.

Example Calculation:

• For a 400 GPM ASP system with a capital cost of $8.00 per gallon:
• Total Capital Cost= 400 GPM × 1440 minutes / day × 8.00 $/gallon=$4,608,000

So, the total capital cost for the ASP system is $4,608,000.

Hydro Reserve’s Modified Ultra-Filtration Approach

Hydro Reserve’s modified ultra-filtration (UF) technology offers a highly efficient solution for treating food and beverage wastewater, addressing many of the limitations of conventional methods.

This approach uses a mechanical barrier instead of bacteria, chemicals and aeration to filter contaminants, providing several key benefits:

Smaller Footprint: The compact design of the modified UF system requires significantly less space compared to traditional biological treatment methods, making it ideal for facilities with limited space. Typically, it occupies less than 700 square feet for a 400 GPM system.

Cleaner Water Output: The UF technology produces cleaner water by effectively removing TSS, oil and grease and BOD through fine filtration, resulting in high-quality effluent suitable for various reuse applications.

Mechanical Barrier: By employing a mechanical filtration process, the system avoids the complexities and maintenance issues associated with biological treatment. This approach ensures consistent performance without the variability linked to biological processes.

Energy Efficiency: Hydro Reserve’s UF system consumes less energy compared to aeration-based technologies, reducing operational costs and the facility’s environmental footprint.

Cost Efficiency: Investing in a Build Own Operate Maintain model (BOOM) Hydro Reserve helps food and beverage processors reduce costs by taking complete ownership and responsibility of the ongoing operation of the system. With a pricing model based on both flow rate and contaminant levels it presents a highly economic way to treat food and beverage wastewater without hidden costs, the requirement for wastewater staff or the need to pay for fluctuating volumes of chemicals.

Reduced Maintenance: The mechanical nature of the UF system simplifies maintenance, requiring less frequent intervention and lowering long-term operational costs.

Conclusion