Choosing the Best Anaerobic Digester System for Your Needs

Are you considering a business anaerobic digester? 

The proper system for your needs is essential. Finding the correct anaerobic digester system might be difficult with so many possibilities. Do not worry—we can help. 

This article will help you choose the best anaerobic digester system for your needs. We have systems to handle organic waste in agriculture and transform food waste into biogas in food processing. We will discuss anaerobic digester types, their benefits and cons, and how to choose one. You’ll learn anaerobic digester systems and be able to choose the right one after reading this article. 

Don’t be deterred by anaerobic digester complexity. Let us simplify and provide information to help you decide. Let’s locate your ideal Anaerobic Digester System.

Why Do You Need An Anaerobic Digester?

Effective waste management reduces landfill utilization and environmental implications by efficiently processing organic waste.

Biogas Production

Biogas can be utilized for electricity, heating, or transportation.

Nutritional Recovery

Improves soil health and reduces chemical fertilizer use by producing digestate, a nutrient-rich byproduct.

Independent Energy

Provides local renewable energy, lowering fossil fuel use and improving energy for industrial power plants.

Economic Benefits

Reduces waste disposal expenses and generates energy and nutrient sales.

Odour Control

Minimizes odours associated with organic waste by containing and digesting materials in a controlled environment.

Greenhouse Gas Reduction

Captures biogas from landfills to reduce methane emissions and mitigate climate change.

Promotes sustainability by transforming trash into usable resources, and supporting circular economy projects.

How To Decide Which Anaerobic Digesters Is Best For You

The optimal anaerobic digester system for you depends on various factors. Try this systematic strategy to make an informed choice:

1. Evaluate Feedstock

• Waste Type: Determine the organic waste you will process water treatment(e.g., agricultural, food, manure).
• Quantity: Determine digestible feedstock volume. The digester size and technology will depend on this.

2. Assess Digestive Technology

• Continuous/Batch Systems: Choose continuous flow digesters for continuous feedstock input or batch digesters for discontinuous batches.
• Compare high- and low-rate digesters. Advanced technology may be needed for high-rate digesters to manage increasing organic loading rates.

3. Design digesters

• Type of Digester:

1. For huge volumes of liquid manure, a covered lagoon is easy but inefficient.
2. Plug Flow: Effective for agricultural waste and high-solids feedstocks.
3. Complete Mix: Suitable for continuous feeding and varied feedstocks.

• Anaerobic Membrane Bioreactor (AnMBR): It produces high-quality effluent through anaerobic digestion and membrane filtration.

4. Estimate Energy Production

• Based on feedstock properties, calculate biogas yield. Energy-rich feedstocks produce more biogas.
• Consider using biogas for energy, heating, or automobile fuel.

5. Consider Economics

• Equipment and installation costs should be considered while choosing a digester.
• Maintenance, labour, and utilities are operating costs.
• Money incentives: Look for grants, subsidies, and tax credits to reduce costs.

6. Assess Regulatory Compliance 

• Permitting Needs: Learn about local anaerobic digestion regulations and construction and operating permits.
• Environmental Impact: Evaluate the technology’s environmental impact.

7. Assess Site Conditions 

• Space Availability: Have enough acreage for the digester and any additional equipment (storage tanks, gas handling systems).
• Water and power for digestion: Verify the availability of these resources.

8. Ask Experts

• Engage Professionals: Anaerobic digestion consultants and engineers may assess your needs and options.
• Learn from current facilities’ experiences and issues by visiting them.

9. Consider Future Scalability

• Flexibility for Expansion: Consider whether the digester can be adjusted to handle future feedstock or energy increases.

10. Sustainability

• Durability and Maintenance: Assess the digester’s lifespan and maintenance convenience to ensure reliable operation.

Size And Capacity Requirements

To determine the size and capacity of wastewater treatment for industrial systems, various criteria must be addressed while designing an industrial wastewater anaerobic digester system. Consider these crucial factors:

1. Feedstock Features

• Type of Wastewater: Type of industrial water treatment (food processing, dairy, pharmaceuticals).
• Organic Loading Rate (OLR): Calculate the digester’s biodegradable organic matter processing capacity (kg of COD per cubic metre per day).

2. Digester Volume Calculation

• Time Retained: Determine the hydraulic retention time (HRT), usually 15–30 days for industrial applications, based on feedstock properties.

3. Estimating Biogas Production

• Yield: Estimate biogas production from feedstock type and organic content. Yield is usually reported as cubic meters of biogas per kilogramme of COD eliminated.

4. Extra Capacity Considerations

• Safety and Operations Margin: Add a digester buffer for wastewater flow and composition changes.
• Plan for extra capacity to store sludge, which may need frequent removal and treatment.

5. Digester Type 

• Design Options: Based on wastewater characteristics and efficiency, choose a plug flow, complete mix, or anaerobic membrane bioreactor digester.
• Configuration: The design (vertical or horizontal) and materials (steel, concrete) also affect capacity and building costs.

The Types Of Anaerobic Digestion

Anaerobic digestion produces biogas and nutrient-rich digestate by breaking down organic waste without oxygen. It often generates renewable energy and treats organic waste and wastewater. Here are the primary anaerobic digesting methods:

• Wet Digestion:

In this type of anaerobic digestion, water mixes with organic waste or slurry to make a moist slurry. Waste is held in a digester where bacteria break down organic stuff without oxygen. Sewage sludge, food waste, and animal manure benefit from wet digestion.

• Digestion, Dry Or Batch: 

Dry anaerobic digestion decomposes organic waste without water. Agricultural crop residues, yard garbage, and organic components of municipal solid waste are solid or semi-solid. Garbage decomposes without oxygen in a reactor or digester. Due to reduced microbial activity without water, dry digestion may require longer retention durations.

• Continuous Flow Digestion Process: 

In continuous flow digestion, organic waste is fed into the digester and the digested material is removed simultaneously. It produces biogas from various organic waste sources on a huge scale. Moreover, continuous-flow digesters function continually, assuring a constant supply of organic waste and biogas production.

• Plug-Flow Digestion:

It is a form of continuous-flow digestion where organic waste enters one end of the digester and flows sequentially. This design prolongs trash retention and uniformly decomposes it. Plug flow digesters can manage high solids and diverse organic wastes.

• The Up-Flow Anaerobic Sludge Blanket Processes: 

UASB is a specialised form of anaerobic digestion used to treat industrial wastewater. After wastewater is introduced at the bottom of an up-flow reactor, a dense blanket of suspended anaerobic sludge converts the organic matter into biogas. The gas rises to the reactor’s top, while treated effluent exits the top or sides.

Industrial wastewater treatment with anaerobic digestion is compliant and environmentally friendly. Anaerobic digestion helps enterprises meet regulations, lessen their environmental impact, and contribute to a circular economy by recovering energy and nutrients from waste. WOG Group effluent treatment projects have made us a leading wastewater treatment plant supplier. Our wastewater treatment plants produce high-quality water with less energy and chemicals.