Cleaner production – a solution to pollution?
Key text
This topic is sponsored by the Environment Protection Authority, Victoria and the Australian Government's National Innovation Awareness Strategy.
What is cleaner production, and how can it help reduce pollution loads?
To get an idea of what cleaner production means, let's look at one example of how cleaner production methods turned waste into an asset.
Case study
In the early 1990s, an orange juice manufacturer in Victoria had a waste problem with orange peel. The Original Juice Company squeezed up to 90,000 tonnes of fresh citrus fruit each year – that's a lot of oranges, and a lot of peel left over.
In a dry form, the peel could be sold as a high protein stock feed, but to achieve the necessary degree of dryness it needed pressing. This generated up to 4 million litres a month of effluent – liquid waste high in citrus oil and sugars. Discharged into a nearby waterway, the waste created environmental problems. Of particular concern was biochemical oxygen demand (Box 1: What is pollution?).
But with some creative thinking, the orange-peel problem was turned into an asset. The company realised that citrus oil and sugar were potentially marketable products. By investing in equipment worth just over $1 million, it now saves about $450,000 each year in waste disposal costs and earns $250,000 a year in citrus oil and molasses sales. The company profit has increased, and the pollution load on the environment has decreased.
Cleaner production: a win-win situation
The United Nations Environment Programme has defined cleaner production as 'the continuous application of an integrated environmental strategy to processes, products and services to increase efficiency and reduce risks to humans and the environment'. The idea is that industrial processes can often be improved in ways that not only reduce the amount of waste, and therefore pollution (Box 1), but also save or make money for the company or agency, in other words a win-win situation.
In the past, polluting companies concentrated on treating the waste generated by an industrial process in an attempt to reduce its impact on the environment, but often there was no attempt to reduce the overall level of waste. With cleaner production, the emphasis is on waste minimisation – reducing the amount of waste produced in the first place.
Cleaner production is most often applied to manufacturing processes, but it is also relevant to other sectors of the economy, including agriculture, mining and the provision of services. Whichever the sector, the underlying principle is the same. Instead of relying on penalties that force companies to treat their waste, cleaner production offers rewards – increased profits and an enhanced environmental image – to those who can reduce their overall level of waste.
Redefining waste
The example of the Original Juice Company shows that one of the principles of cleaner production is to redefine 'waste'. The original product for the company was orange juice, but sometimes the leftovers can be valuable – in this case, the peel could be converted into a number of useful products that could then be sold. The leftovers are no longer wastes that create environmental problems, but are products in themselves.
Reducing disposal fees
Not so long ago, the polluting company didn't bear the cost of waste disposal, the environment did. In many Australian States and Territories these days, companies discharging pollutants into the environment must purchase a licence to do so.
Cleaner production can lead to savings in waste disposal costs. For example, one of Australia's largest yarn manufacturers, Australian Country Spinners, used 250 litres of water and 3 kilograms of chemicals to produce each kilogram of finished yarn. This produced considerable effluent, which was discharged into a local waterway after treatment at a treatment plant.
The company began investigating cleaner production techniques in 1992.
The first step was to produce a waste audit – this measured all waste streams, identified the 'dirtiest' elements in the production process and highlighted areas where improvements could be made and effluent reduced.
In a sense, the changes were all about improving efficiency. The company estimated that about 90 per cent of the effluent was relatively clean. Mixing it with dirtier effluent at different stages of the production process needlessly increased the overall disposal burden. By segregating waste liquids, the company was able to recycle large amounts of clean wastewater within the plant, thereby significantly reducing total water usage. It also introduced new dyeing technology that reduced chemical usage per kilogram of product and eliminated some waste streams altogether.
As a result of more than 50 improvements costing about $150,000, the company benefited to the tune of $1.1 million over 3 years – particularly through reduced trade waste charges, but also through reduced water and energy bills – and improved the quality of its product at the same time.
Savings in raw materials
Other cleaner production technologies can save raw materials, which can reduce costs and pollution loads. The W.L. Allen Foundry Company, for example, uses sand as a raw material for moulds in the manufacture of alloy iron and steel castings. Before implementing cleaner production, the used sand was discarded once the moulds were broken and the cast removed. Each year, the company dumped 3500 tonnes of sand as landfill.
The company determined that this sand could be reclaimed and reused if a number of substances were removed. These included conglomerates of sand particles, binders (used to bind sand particles together so that the mould will stay in shape), additives and foreign material such as metal particles. In addition, the reclaimed sand needed to be dry and at an acceptable temperature; it needed to have similar bonding properties to 'new' sand; and it needed to produce results similar to those produced with new sand.
At a cost of $325,000, W.L. Allen introduced a system that would achieve these results. Sand aggregates are now broken down in a sand blaster and foreign metals removed by a magnetic separator and air curtains. In addition, the sand is impacted on an impact plate to break it down into individual grains and to remove the binder coat. A heating and cooling system allows temperature control of the reclaimed sand, which is then mixed with new sand at a ratio of 3:2. By introducing this technology, the company saves about $75,000 per year in the purchase of new sand and about $48,000 in disposal costs.
Towards cleaner production
Cleaner production can save companies money in ways other than those mentioned above. For example, savings – and environmental gains – can be made through energy conservation and by replacing toxic chemicals (the disposal of which is expensive) with more benign chemicals.
But the introduction of some cleaner production methods will not always produce a financial windfall for companies. In some cases, cost savings brought about by improved production efficiency may be outweighed, in the short term at least, by the cost of introducing new technologies.
Nevertheless, other benefits including improved employer-employee relations, safer working conditions and improved internal monitoring may tempt industries to introduce cleaner production even when it involves a net cost. In an era of corporate social responsibility, many companies are employing techniques such as Life Cycle Analysis to examine the impact of their products on the environment throughout their life (Box 2: Mobile phones from the cradle to the grave).
If adopted broadly, cleaner production could play a significant role in reducing pollution and resource depletion. It won't end pollution, because even cleaner production produces some waste. But cleaner production is better than the situation in the past, when both industry and the environment lost out.
Boxes
1. What is pollution?
2. Mobile phones from the cradle to the grave
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Page updated November 2008.