How is water used in manufacturing?
- Identify and prioritise the major water using practices, and the opportunities for reusing wastewater.
- Conduct a water audit of the site. This may involve a detailed inventory of existing plant, equipment and plumbing, and operational procedures. Advice on conducting water audits is provided in the texts listed in the resources section. Alternatively, many water retailers offer water audits as part of their business support services.
- Brainstorm possible solutions, using members of the water conservation team and experts on water conservation and cleaner production. The findings and recommendations from the water audit are a good place to start.
- Develop a standard reporting procedure for water issues. This should include: - Total water use over a defined period (week, month, quarter) - Water use performance of major plant and processes - A comparison to previous water use patterns and identified goals - Issues that need addressing (such as leaks), and responsibilities for action.
Educating staff
- Establish a water conservation education program that encourages all staff to use water sparingly.
- Engage all levels of staff in brainstorming and developing water saving initiatives.
- Consider holding water efficiency awards to encourage staff to get involved. This is also a good way to collect and develop water saving ideas.
Leaks
- Use water meter data and reports to identify leaks early.
- Replace worn seals on water pipes.
- Repair leaking pipes, valves or other equipment.
- Monitor wash tanks and storage tanks to ensure they do not overflow.
- Ensure all taps are turned off when not in use.
On the production line
- Adjust flow rates to the minimum required for the operation.
- Make sure water sprayers and jets turn off when the production line halts or ceases. Use timers or motion sensors to do this.
- Install high pressure, water efficient spray jets.
- Install flow restrictors and regulators where appropriate.
- Use pedals and timers to deliver water only when needed.
- Use fogging nozzles to cool products.
- Inspect nozzles for clogging regularly.
Washing and cleaning
- Clean plant areas and paths with brooms rather than water.
- Make sure all hoses are fitted with trigger-operated guns.
- For equipment that needs to be cleaned regularly, consider using process water from other areas.
- Use high-pressure nozzles where possible.
- Consider alternative methods of cleaning, such as high-pressure air jets.
- Where possible, wash items in water baths rather than under sprinklers.
- Agitate rinse baths with air or mechanically, to increase rinse water life and efficiency.
- Use scrapers and brooms to remove residue build-up in plant machinery.
- Regularly check that spray nozzles are aimed correctly.
Water recycling
- Identify processes where the discharged water can be reused. This includes water from equipment cleaning, filtered backwash water, final cooling and cleaning water, and water used for transport
- Identify areas for using the recycled water. These may include: - Cooling tower makeup water - Industrial processes - Equipment cooling and cleaning - Garden irrigation
- Check to see where water treatment is necessary before recycling
- Consider other options for keeping wastewater on-site that can potentially add-value to the company’s use of water. Wastewater often contains high levels of nutrients and other by-products. If treated appropriately, these by-products can be reused or sold as products such as mulch or animal feed.
- Consider waste treatment processes such as wetlands, composting and worm-farms.
Cooling towers and process water cooling
- Use rainwater, dam water or process water to supplement fresh makeup water for cooling towers.
- To avoid overflowing, ensure the float valve and seal of the makeup supply is set correctly.
- Eliminate water lost from wind drift by using baffles and drift eliminators.
- Ensure blowdown water use is controlled properly.
- If cooling water cannot be recirculated, reuse this water in other processes such as cleaning.
- Use air-cooled rather than water-cooled ice making machines.
- Regularly check for leaks in the system.
Around the site
- Use rainwater for toilet flushing and garden irrigation. See savewater.com.au’s sections on Rainwater Harvesting and Gardens for more information.
- Install water efficient products in staff bathrooms, change rooms and kitchens. Use savewater.com.au’s section on The Home for information on water efficient products.
- Disconnect or remove taps that are no longer in use.
- Wash vehicles in designated bunded wash bays that capture water for recycling or garden irrigation.
- Investigate opportunities to improve the stormwater management on the site. This will present opportunities for using that water, as well as reduce the risk of unwanted discharges from the site.