The Importance of Anaerobic Digestion Within The Wastewater Treatment Process
Anaerobic digestion (AD) is a key process in wastewater treatment, particularly in the management of sludge and organic waste.
In any wastewater treatment plant removing waste, particulate and organic matter is an important step, which is crucial for improving water quality, preventing contamination and protecting public health.
The Anaerobic Digestion Process
AD involves the breakdown of organic matter by microorganisms in the absence of oxygen, resulting in the production of biogas (primarily methane and carbon dioxide) and a stabilised residue or biosolids. It is used to treat wastewater once it has already passed through primary and secondary treatment stages.
Anaerobic bacteria, which are more efficient than aerobic bacteria which require oxygen, break down waste matter. The volume of sludge is minimised and pathogens and odour are reduced. Gases resulting from the process are used onsite for green electricity or heat production, or sold into industry. The remaining biosolids can be used as fertiliser, or boiler feed to produce additional electricity and heat.
The Benefits Of Anaerobic Digestion
AD is an efficient way for wastewater treatment firms to deal with the organic matter found in wastewater, not least because it reduces the amount of harmful bacteria, viruses and parasites present in wastewater and therefore cuts the risk of spreading infections. There are several other reasons why it is an efficient process:
- Reduces Environmental Footprint – By reducing the amount of sludge and producing biogas it cuts the carbon footprint of wastewater companies and can offset energy consumption.
- Lower Chemical Usage – No need to add chemicals like lime or ferric chloride to reduce odours or control pH. Reduced need for flocculants and coagulants to aid in the settling and removal of suspended solids.
- Production of Fertilisers – The remaining sludge, or digestate, can be further processed to recover nutrients like nitrogen and phosphorus which can be used in the manufacture of fertilisers.
- Biogas Production – Biogases are a bi-product of the anaerobic digestion process. These gases can be captured and used to generate electricity, as a heating source, or upgraded to produce biomethane for the national grid.
The Importance Of Utilising The Right Pumps For Maximum Efficiency
AD is far more efficient than aerobic digestion (composting) – it takes up less space and it offers more environmental control. But it’s crucial any system addresses the common challenges to optimise costs and energy consumption/production.
By its very nature wastewater is full of both organic and inorganic particulate such as grit and fibrous rag build up, which can rapidly cause wear and tear, blockages, excessive energy consumption and breakages on pumps designed for clear water.
The kind of pumps required for AD need to be far stronger and able to withstand much greater abrasive forces. AD-suitable pumps must have high wear resistance parts, which are easily accessible, and specially designed pump impellers or geometry.
At Atlantic Pumps we have three types which are efficient in the AD process:
- SlurryPro – These pumps enjoy high flow with increased wear resistance
- LSM – This pump uses a peristaltic-based mechanism developed for high solids sludge. It handles corrosive and abrasive fluids and thickened slurry well
- TORO Progressive Cavity Pumps – These include models designed for longer-life in abrasive slurry typical of the wastewater AD processes.
Here at Atlantic Pumps, we are specialists in pumping abrasive and aggressive fluids, get in touch with us today for all information and enquiries.
