Optimising chemical dosing in a challenging operating climate

Optimising chemical dosing in a challenging operating climate

By: Adeel Hassan of Watson-Marlow Fluid Technology Solutions

Rising operating costs and tightening regulations are presenting major challenges for wastewater treatment plant operators, but better optimisation of chemical dosing can drive efficiencies.

Wastewater treatment providers are facing an extremely challenging operating climate in 2023 and beyond as authorities around the world tighten environmental regulations which govern chemical use and wastewater disposal. They are also coming under pressure from the rapid rise in operating prices and customer expectations on sustainability.

Here are six factors to consider in chemical dosing to achieve the best performance in onsite wastewater treatment (WWT).

1. Stay competitive

Chemical and operational savings are critical to staying competitive in a global market and maintaining cost control. When factoring in the pressure to modernise and increase capacity, it can be a complex task to understand where to make the most effective efficiencies.

Energy consumption is in the spotlight as utilities strive to meet sustainability goals and net zero carbon targets, along with managing rising costs. A changing climate and growing pressure from the public for utilities to reduce waste while minimising environmental impact is also driving change and increasing expectations.

Peristaltic pumps provide highly accurate dosing by enabling precise, incremental, adjustments for various quantities of chemicals. By only using what is needed, chemical quantities and costs are reduced.

2. Keep abreast of regulations

As WWT facilities in the municipal and industrial sectors look to upgrade equipment to meet tightening regulatory demands, regulations themselves are also changing. For example, the European Council Directive 91/271/EEC on urban wastewater treatment, which includes the UK, states that by 2040, all water released into the environment, from treatment plants serving 100,000 people or more, must be free of pharmaceuticals, pesticides, antibiotics, manufacturing chemicals and other harmful substances –resulting in the need for increased treatment.

In addition, the UK Government has released a ‘Plan for Water’ in April 2023 to strengthen regulation by developing new proposals to restrict or ban the use of ‘forever chemicals’ (known as PFAS) which end up in water sources. It also proposes bringing forward the 2040 EU deadline for water utilities to reduce chemicals in wastewater treatment.

As the need for greater transparency around sustainability goals and metrics increases, it is incumbent on suppliers like WMFTS to support clients in optimising chemical use and eliminating the risk of spills of pollutants into the environment. Treated effluent must meet high quality standards before being released into the environment as inaccurate dosing and regulatory breaches can result in large fines and damage to company reputation.

3. Put safety first

The health and safety profile of pumps is an important consideration for plant managers and there are some features to look for to meet high standards of health and safety.

This includes integrated leak detectors which stop automatically and alert operators in the event of a pumphead failure as well as units which are self-contained and, once valves are shut off, a pumphead that can be quickly and easily replaced without tools or spillages for safe maintenance. These features help to minimise the possibility of operators coming into contact with chemicals and prevents chemical spills into the environment. By comparison, other pump types require disassembly for repair and maintenance, risking chemical spillage and exposing staff to potential contact with chemicals.

4. Optimize equipment effectiveness

The right chemical dosing pump offers the opportunity to help operators save on capital expenditure and demonstrate best practice. Long established in the market, a peristaltic pump has a long product life and does not require pulsation dampeners, degassing valves, or back pressure valves. They offer quick maintenance at longer intervals – reducing the impact of process downtime, rapid process recovery, and lowering the overall cost of ownership.

The high accuracy enables the use of more concentrated chemicals and smaller, more efficient, dosing systems, which in turn reduces both energy and transport costs. Furthermore, accurate, linear, and repeatable chemical dosing allow the use of less chemicals, even with varying process conditions.

5. Boost sustainability

Municipal and industrial organisations are increasingly seeking to reduce vulnerability to a challenging operating climate through conservation and reuse of water – with some undertaking onsite assessments of wastewater treatment plant operations at every stage of the process, to ensure they are operating as efficiently as possible. The benefits will be a reduction in water footprint and cost of supply.