Water is becoming an expensive utility. Kate Gallagher, a water use specialist with Envirowise, discusses how manufacturers can reduce water consumption costs
With news of drought and water restrictions hitting the headlines more and more regularly, the UK, like the rest of Europe, is beginning to wake up to the fact that rainfall is less predictable and water is not as plentiful and cheap as it once was.
Water is one of our most valuable resources and usage should be managed with care. There is much emphasis placed on household consumption, however, with industry and commerce responsible for a third of water use in the UK - at an estimated current cost of £1,014m - all companies need to take a closer look at how much of their profits are being poured down the drain.
In the face of ever-growing international competition, pharmaceuticals manufacturers are looking for ways to improve their performance. Water minimisation is actually one of the simplest ways that pharmaceuticals manufacturers can achieve cost savings. Research has shown that plants which have never previously examined their water consumption can usually expect to make savings of around 30% on water and effluent bills simply by implementing straightforward water management measures.
However, it is not only the basic supply and discharge costs that must be considered as a drain on profits. Associated costs related to pumping, maintenance, capital depreciation and treatment can add up to a considerable sum.
Taking action could also help the chemicals industry meet a goal set by the Chemical Industries Association (CIA) to cut water use per tonne of production by 20% by 2010. This target is part of the Association's wider commitment to encourage its members (which include pharmaceutical companies) to work towards a more sustainable future.
Dr Anne-Gaelle Collot, Environmental Protection Policy Advisor at the Association comments: 'One of the CIA environment sustainable development goals is to achieve a 20% reduction in water usage between 2000 and 2010. Since the year 2000 our members have continued to reduce their water usage and are well on the way to meeting the 20% reduction target by 2010.'
monitor usage
In terms of practical steps pharmaceuticals manufacturers can take, the measurement and monitoring of usage is vital for any company aiming to reduce waste. Rather than simply metering water input as a whole, Envirowise recommends installing meters on each process line, or on each water inflow point on a process.
It is important that the water flow rates displayed on meters are not just fitted to pipelines, as these are often out of sight. Transmitting a flow signal to the process operator can allow more effective use of the information. Some existing turbine type flow meters - with simple dial displays - can be upgraded in situ to provide a pulsed flow signal. This signal can either be transmitted to the site control system or, with suitable cables and an interface board, be logged and displayed on a standard office computer.
An alternative approach is to measure the flow through the pipework simply by using a bucket (of known volume) and stopwatch. While this method doesn't allow for ongoing monitoring, it is a simple and no-cost way of spot-checking the level of water use on-site.
Once measurements have been recorded, the company is armed with an exact knowledge of water use throughout the plant, and can then address particular areas where water is being used excessively. Keeping regular records of water usage allows the company to review the success of any water minimisation practice and helps to prevent irregular consumption.
For example, leakage is a common and easily preventable problem. Regular monitoring means that leaks from mains water are more easily identified and can be repaired quickly, preventing potentially damaging and costly flooding. In addition, investing in inexpensive blow out preventers could reduce the likelihood of leaks.
Most overflows run to drain without being measured. The flow rate during overflow can be as high as the delivery pumping flow rate. However, overflows are usually due to poor control, which can easily be gained using simple shut-off sensors and on/off control systems for pumps or shut-off valves. It is important to monitor this equipment regularly to ensure that it has been set correctly and is not faulty. recycle and reuse
The re-use of rinse water is another method that can result in savings. Wash water is often flushed down the drain on the basis that it has been "used". Careful examination of the quality and availability of wash water, together with an understanding of water requirements elsewhere on site, may reveal opportunities for re-use. Typical final uses of wash water include first wash-down and rinse of floors and containers, and the making up of raw material slurries.
During cleaning, large quantities of water from hoses are frequently used to wash slurries from floors and walls down the drain. Hand-held scrapers will move most of the slurry across the floor efficiently. The combined use of scrapers, brushes and hoses can reduce the time taken to clean an area. Removing slurries from surfaces before they start to dry or pre-wetting dry areas can reduce both the volume of water needed for wash-down, and the time taken. Pipelines can often be cleaned effectively using "pigging" systems. A "pig" is typically an engineered plug or ball that fits inside the pipe and is pushed through mechanically or hydraulically to clear material.
Other tactics for boosting water re-use include Cleaning-in-Place (CIP) systems, which are used to clean process plants in situ. The systems can re-use final rinse water for first rinses and re-use concentrated cleaning chemicals many times for intermediate washing cycles. And water which requires treatment to remove unacceptable impurities could benefit from one of the following technologies:
- filtration
- clarification/sedimentation
- centrifugation
- flotation
- ion exchange
- distillation/stripping
- absorption/adsorption
Envirowise provides sector-specific advice and practical guidance on all areas of resource efficiency. We would recommend that pharmaceuticals manufacturers looking to take steps towards reducing water consumption visit the website at www.envirowise.gov.uk/watertools where a range of free information and tools are available.
In particular, the online water tools provide step-by-step guidance on water minimisation and effluent generation, from the initial stages of measuring current usage, through to implementation and evaluation. The water account tool allows businesses to benchmark their water use against that of other businesses in the sector. In addition, the WaterNet search tool enables users to search for publications produced by Envirowise and other key stakeholders that are tailored specifically to helping the manufacturing industry cut water waste.
Envirowise is a UK government-funded body that can provide companies operating in the UK with confidential advice on a specific issues through its helpline (T 0800 585 794). Some companies may also be eligible for a free on-site resource efficiency review from a specialist adviser.
Envirowise tips
- Always measure and monitor the amount of water you use. Compare water use each year and also against production output.
- Take meter readings regularly and carefully - this will help identify changes in water use.
- Consider recirculating cooling water through a closed loop system as this can reduce water consumption significantly.
- Turn taps off fully and replace leaking hoses and worn tap washers for a quick and cheap way of saving water. In staff washrooms, push-button taps can use up to half the water used through conventional taps.
- Consider using lower quality water such as recycled process water for purposes where quality is not critical.
- Reduce the amount of clean water used in every toilet flush by fitting a water displacement device into cisterns - these are often available free of charge from your local water company
- Make sure staff are fully aware of the importance of water minimisation. Run a staff competition to identify water-saving ideas or organise a brainstorm. Consider appointing "water wardens" to take responsibility for water minimisation measures in each area of your site.
- Keep water-using equipment well maintained and check it periodically for leaks. Ensure staff are encouraged to report leaks and that leaks are repaired quickly.
- When purchasing new equipment, take its water efficiency into account. It may be more expensive to buy water efficient equipment, but it may have a short payback period due to the water savings achieved.
Genzyme gets wise to water waste
Leading pharmaceutical manufacturer Genzyme recognised the business case for addressing water consumption in its operations early on and, through the implementation of a systematic programme of water reduction, has made estimated total savings of £50,000 in two years.
The plant, based in Suffolk, is a serious water-user with a daily consumption equivalent to that of 600 households. Genzyme saw that the cost of water to the business was much more than the £1 per tonne purchase price, as the purification process it needs to go through adds an additional £10 per tonne. The company realised that it would have to use water more efficiently if it was to expand the business and become more competitive on an international stage.
The washing of the polymer product is a process central to Genzyme's manufacturing operation, and indeed, the most water-intensive. The second stage of the washing process alone uses 1500 litres per hour - 10 times the amount the average person uses in an entire day. The product has to pass through a number of washes, and the company found that by recycling water from the final rinse for re-use in the first stage of a different wash, significant amounts could be saved.
Through the process of measuring and monitoring, the company was able to identify a leak in the boiler plant heat exchanger. The simple replacement of this device saved the company a great deal both in the short and longer term. Automated continuous monitoring equipment was also installed and procedures for water supply shut-off were improved.
Following advice from an Envirowise adviser, Genzyme has recently invested in new technology to recycle treated effluent, which will only multiply savings. Nick Hodgson environment manager at Genyzme is pleased with the company's achievements: "The company is also now operating well within trade effluent volume limits, which has opened up our expansion potential. So far, we have reduced consumption by 20% - achieved simply by looking at how water used in company processes could be better managed."