Effluent water treatment; costs, challenges and opportunities
Water supply and disposal costs are rising and increasingly subject to stringent environmental controls and regulations. In response, companies (especially but not exclusively in the Food and Beverage sector), are focussing on more intelligent water management across the cycle. With much of your process water capable of re-use and scope to get additional cycles of re-use out, companies are becoming more receptive to water technology and smart processes which are now proven. Are you seizing site operating economies and realising a more ‘circular economy?’
What's the cost of trade effluent disposal?
As water costs are rising so are water disposal costs. And the more contaminated your effluent is, the more costly its disposal will become. Increasingly stringent discharge conditions continue to be applied to meet tightening environmental standards. As a result many businesses in the UK are finding their effluent costs are actually exceeding their annual fresh water usage bill. All of this is presenting new pressures for industry to find more sustainable and cost effective means of effluent disposal.
Fortunately, more intelligent water management practices implemented across the waste life cycle can reduce the amount of water businesses need to draw from the water supply, while reducing the quantity and improving the quality of waste they discharge back into the drains. As a result, environmental impact and discharge costs can be significantly reduced while businesses can gain further cost savings by consuming less fresh water.
Techniques for effluent water treatment
Water technology is evolving quickly and today there are a whole raft of waste process water techniques that mean:
- More contaminants can be removed from wastewater before disposal,
- More of your process water can be re-used (often in several cycles)
- Wastewater can be reprocessed and repurposed
These techniques include:
Coagulants and flocculant chemicals used in wastewater treatment, for solids removal, water clarification, lime softening, sludge thickening, and solids dewatering. Coagulation destabilises the suspended particles, while flocculation helps them to bind together so they can be filtered out of the water more effectively. PoIymers are a large range of natural or synthetic, water soluble, macromolecular compounds that can destabilize or enhance flocculation of the constituents of a body of water. Water treatment using these chemicals and processes can result in up to 90% reduction in suspended solids and organic loads, thus reducing the strength and volume of the wastewater for discharge and, therefore, associated disposal costs.
Chlorine Dioxide Generation - chlorine dioxide is an ideal biocide. It is effective at low dosages, with high residual effectiveness and potency as a water disinfectant. ClO2 acts differently to chlorine disinfectant – it is a pure oxidant. It reacts with odour-causing compounds, breaks down phenols and doesn’t produce THMs. Modern Catalytic Chlorine Dioxide Generators (ClO2IX) are able to produce reliable, high purity water, with no taste, colour or residue, that can be recycled and re-used across multiple cycles.
Wastewater to energy through bespoke machines, equipment and processes - re-purposing trade effluent instead of discharging it is being made possible by a whole range of ‘sludge to energy’ technology and heat recovery systems. Output can be sold on to third parties or used internally to help waste disposal operations become cost neutral.
By applying these techniques you can:
- Reduce the cost/m³ of your trade effluent
- Reduce the sludge volume leaving your site that attract increased disposal charges
- Recycle treated effluent water for repeated use
- Process, repurpose and even sell trade waste to offset disposal costs
How can you identify savings, opportunities and potential challenges in your effluent water disposal?
A trade effluent audit looks at your existing output to identify ways your business might be able to save money by treating and recycling wastewater, and otherwise reducing the volume of effluent you are discharging to the sewer system. It can also monitor your output to ensure you are currently compliant with regulatory requirements.
Auditors look at your existing effluent so see exactly how it’s contributing to your business costs, and whether there are any usage trends that could suggest opportunities for more efficient treatment or reuse. They can also benchmark your discharge against businesses working in similar sectors of the same size and scale.
With the right insight and implementation, modern effluent water treatments not only promise cost savings for business, but practical ways they can become part of the ‘circular thinking’ of a greener economy.
Practical ways to get started
Here are key questions to consider designed to help you make better informed operating decisions:
- Are we confident our on-site water re-use cycle is fully optimised?
- Are effluent and discharge operating costs acceptable and is there scope for further reduction?
- What is involved in more efficient water re-use on-site and what will site improvements cost?
- What does the ROI look like and can we recover capital investment employed within 12, 24 or 36 months?
- What portion of investment can be financed making capital investment more attractive?
- What on-site competitive advantage can be realised?
- Can we leverage all this and tell a better sustainability and environmental story to customers?
It isn’t just food and beverage companies who are leading the demand for tighter water management across the lifecycle. Any site with substantial water related usage and environmental regulation adherence demands interested in pursuing step-changes in water, energy and environmental running, can and should be looking at continuous improvement.
For capital investment projects of £10,000 - £150,000+, asset finance is available for eligible companies incorporating the first year’s maintenance related costs. This enables companies to realise site operating and environmental improvements without a significant upfront capital outlay or dramatic impact on P&L.
Water, Operating and Efficiency Managers have very real and discernible options open to them which enable them to take bold steps in water management, re-use and secure financial and environmental benefits in parallel.
Topics: Wastewater Treatment
Written by Jon Greaves
Jon has progressively worked through operational roles, account management, technical management, and senior management roles over the last 16 years within one of the group companies before moving into the role of Water and Air Managing Director. Jon has experience across multiple sectors of water and air compliance, including district energy networks; data centres; healthcare; food and beverage and facilities management. Jon acted as a corresponding steering committee member on CIBSE CP1 – Heat Networks Code of Practice for the UK released in 2020.