Food industry wastewater treatment: what you need to know

The industry produces large amounts of wastewater containing high levels of organic matter, fats, and other contaminants that must be removed before water can be safely released or reused. 

In this article we look at the characteristics of wastewater produced by the food industry and how Aqua Advice can help food and drink processing companies meet compliance demands, protect the environment and save money.

Characteristics of food industry wastewater

The food industry creates large amounts of wastewater containing:

• Fat, oil and grease
• Blood contaminants
• Protein
• Sugars and starches
• Whey
• Cleaning chemicals

The challenges of food industry wastewater treatment  

The high levels of organic matter in food industry wastewater pose unique challenges for effective treatment:  

Clogging of equipment  

Solid particles are common in this type of wastewater and can clog pipes and equipment if not properly removed, resulting in costly damage and downtime.

Fats and oils can also coat treatment surfaces and reduce efficiency.

PH levels 

Cleaning cycles can cause pH levels to fluctuate, which can disrupt biological activity. Furthermore, wastewater may have varying pH levels depending on the products being processed.

Sludge production 

The high concentrations of biodegradable organic matter in food industry wastewater generates disproportionately large volumes of sludge when treatment systems break down these organic loads.

Algal bloom 

Nitrogen and phosphorus levels in wastewater can cause algae to bloom in receiving waters.

Food industry wastewater legislation  

In addition to general wastewater legislation, UK food and drink processing plants must also comply with industry-specific laws such as:

• Water Industry Act 1991
• Food Safety Act 1990
• Environmental Protection Act 1990
• Separation of Waste (England) Regulations 2024

Non-compliance with these regulations can results in enforcement actions including prosecution and financial penalties.

Wastewater treatment and the food industry 

Due to its industry-specific challenges, food industry wastewater requires tailored treatment approaches. These can include:  

Biological treatment  

• Activated sludge: uses microorganisms to break down organic waste in wastewater.
• Anaerobic digestion: breaks down organic materials without oxygen, producing biogas as a byproduct.

Chemical treatment 

• Chemical precipitation: removes dissolved solids and metals from wastewater by adding chemicals that cause contaminants to form solid particles, which can then be filtered out.
• pH adjustment: neutralises acidic or alkaline effluents before further treatment or discharge.
• Coagulation and flocculation:  help remove suspended particles using chemicals to make small particles clump together, making them easier to remove through settling or filtration.

Advanced filtration systems 

• Membrane filtration: removes fine particles and dissolved substances using different types of membranes, such as microfiltration and ultrafiltration.
• Reverse osmosis: treats high-salinity wastewater to produce high-quality water suitable for reuse in food processing operations.
• Activated carbon filtration: removes organic compounds and improves water taste and odour.

Food industry and opportunities for water reuse 

The food processing industry is one of the largest consumers of freshwater, requiring its use at several stages including:  

• Production
• Cleaning
• Sanitising
• Cooling
• Material transport

Effective wastewater treatment can help mitigate the impact of water consumption by reusing treated water in production, cleaning or irrigation.  

Identifying the right treatment approach – how Aqua Advice can help 

Wastewater treatment plants play a crucial role in the food industry, removing contaminants and ensure water can be safely released or reused.

Aqua Advice can plan, design and install effective, bespoke treatment methods to solve food and drink industry challenges, improving efficiency and ensuring compliance.

Furthermore, using advanced technologies, we can optimise existing, upgraded or new treatment plants to reduce freshwater consumption and lower costs.

We can also provide staff training to ensure operators need to understand the treatment plant’s processes and how to respond to issues, whilst offering regular audits help identify areas for improvement. 

Get in touch with Aqua Advice today to discuss your wastewater treatment requirements.    

Frequently asked questions about wastewater treatment and the food industry 

What are the most effective methods for treating high-strength wastewater from food processing? 

Effective wastewater treatment methods for wastewater produced by the food industry including biological treatment (such as activated sludge and anaerobic digestion), chemical treatment (such as chemical precipitation and pH adjustment) and advanced filtration systems.