At a time when industrial companies are ramping up efforts to limit environmental impact, David Steven, Technical Service and Sales, Scotland,  at Atana part of WCS Environmental Engineering (WCSEE) says attention is turning to more sustainable chemical choices for wastewater treatment.

There has been a significant shift in focus from industrial water users over the last two years, with the vast majority now committed to becoming more sustainable in their operations. These commitments align with ambitious net zero carbon targets announced by the UK government in 2019, followed by individual industries, including food and beverage and water utilities.

While historically, onsite effluent treatment may not have been a priority area for companies, carbon commitments, alongside tightening trade effluent consents and rising customer expectations, mean robust, sustainable processes are more important than ever.

The good news is, chemical-based solutions, including organic options, do not only treat wastewater to the high standards stipulated by water companies, they can also contribute to carbon reduction and sustainability targets.

Organic solutions

WCSEE, supply a comprehensive range of organic chemicals from sustainable sources to support industrial wastewater treatment processes, while reducing environmental impact and carbon use.

A study undertaken by the University of Aberdeen on the effect of the organic chemistry had on biological wastewater treatment confirmed there was no negative impact on performance. The Cofloc tannin-based products enhanced removal of chemical oxygen demand (COD) in the settling process and was proven to be biodegradable under the tested conditions.

Two key ranges of products have been introduced:

  • TRUFLOC® synthetic water dispersion polymers, which are 60-70% biodegradable in 20 days. They are free of surfactant and solvents and their manufacturing process has a low environmental impact in comparison to other mineral oil-based polymer manufacturing processes.

TheTRUFLOC range includes two water-based polymers: anionic, which has 50% of the carbon footprint of oil-based emulsion polymers; and cationic, which has 70% of the carbon footprint of oil-based emulsion.

  • COFLOC® low molecular weight organic coagulants, which have a biodegradability of 100% in 20 days and are produced from tannins extracted from the bark of the Acacia mearnsii tree (black acacia). Use of these chemicals has a significant impact on the operational carbon footprint of treatment works, due to sequestration of carbon dioxide during the trees’ natural growth cycle.

Chemical-based treatment trials

Onsite trials of the entire chemical range, including sustainable chemicals, are offered as standard by WCSEE. This includes hire of equipment used in the treatment process, such as dissolved air flotation (DAF) units, lamella separators and dewatering screw presses.

A trial ensures the correct chemical combination is applied when embedding new, or enhancing existing, treatment processes. Initial testing is undertaken in a lab, and then upscaled for a trial onsite, using hire equipment if required. Trials can be set up quickly, take approximately one week to run and provide tangible evidence of how the process will work at full-scale.

An initial survey of the wastewater treatment process, including jar testing, would determine the potential for introduction of the organic chemical ranges. The team would submit a detailed report on each site surveyed.

WCSEE would then carry out an onsite trial to demonstrate the effectiveness of the new chemistry regime. All trials are designed to remove any risk to the client’s existing process and are managed by qualified engineering and chemical consultants.

 

The coagulation process in water treatment

Overall cost-savings

Trial results will also give an accurate picture of the cost of a permanent solution, taking into account ongoing chemical and physical process costs. Decision-making is not only about the price per litre of chemical – clients need to know the whole-life cost of any required investment.  The cost benefit of having the correct process in place can be significant.

This information can also demonstrate a return on investment, enabling clients to look at the bigger picture. How much do you need to use for the treatment system to work effectively? What are the associated energy costs of treatment?

Higher quality discharges into the public sewer will lead to lower trade effluent charges from water companies.

What are potential savings resulting from having less sludge to manage? A tannin-based product, for example, will produce around half the amount of sludge of an aluminium-based product, but they achieve the same level of treatment. Disposing of sludge is costly, and rules around sludge management are tightening, which means treatment methods that produce less waste will become increasingly appealing.

Using WCSEE’s green chemical products may mean sludge can be processed in an anaerobic digester, rather than tankered to a landfill site or other costly options. Not only does this represent a potential cost-saving, there is also a contribution to the circular economy of resources as waste is converted to energy and sustainability is embedded in everyday processes.

Trials are used to assess and project annual cost savings, which can then be presented to decision-makers to help build the case for a permanent scheme. At WCS Environmental Engineering, we always encourage clients to take a lifecycle view of the chemicals they use, and the overall cost benefit, from initial purchase to disposal of the final waste product, post-treatment.

Another way companies can reduce chemical waste is through effective control of their processes. Using precise quantities will save on purchase and processing costs and help ensure effluent discharges do not contain potentially harmful levels of chemicals.

Maintaining compliance

Trade effluent discharge permits are only going to get tighter as water companies seek to accommodate multiple challenges, including growing populations, climate change and new pollutants emerging in the environment, which all placing pressure on centralised treatment works. This pressure is filtering down to industrial companies, which are at risk of fines or prosecution if they do not operate within permit conditions.

Processes for treating wastewater vary according to the contaminants present, and include physical, biological and chemical techniques. As a supplier of equipment and substances across the gamut of treatment solutions, along with deep expertise embedded in its teams, the WCS Group, can ensure the most appropriate train of treatment is applied in any scenario. A full turnkey solution is available to enhance treatment processes to meet any environmental consent or trade effluent standard.

Once up-and-running, chemical treatment systems are straightforward to manage and operators can be trained onsite by our technical experts, who can also provide ongoing guidance whenever required.

WPL and Atana are now a part of WCS Environmental Engineering

WCS Environmental Engineering is a part of the WCS Group, which has the in-house skills and expertise in place to deliver full turnkey solutions from influent to effluent, with the capability to close the loop with water reuse.