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Climate change impacts on industrial water, waste and wastewater.
‘The Environment’ has become a feature of the political agenda, but the hot topics have waxed and waned depending on which ideas have captured the imagination at the time. Population growth, water and fuel shortages, renewable energy, pseudo oestrogens, have all been hot topics in recent years, and many still are.
There has been a paradigm shift more recently, however, in that environmental issues are now so well entrenched in the political landscape, that all or most political parties profess to agree on the problems, even if the solutions proposed are often wildly different. Take for example the nuclear debate. No longer an issue of safe energy vs. hazardous waste/nuclear weapons, but now a question of producing enough energy for the future while reducing carbon emissions to the atmosphere.
Even James Lovelock, attributed with the development of the Gaia Hypothesis, suggests that our response to Global Warming is now too little, too late, and that perhaps nuclear energy is the only solution to reducing carbon emissions. The green lobby, long wedded to an anti-nuclear stance finds this difficult to swallow. A recent report from the UK House of Commons Environmental Audit Committee1 (16/4/06) suggested that a decision to commit to nuclear power would not result in benefits soon enough to make a substantial difference to carbon emissions.
In addition, the solutions are no longer quick fixes. Under the EUs Urban Wastewater Treatment Directive (21/5/91), a programme of installing upgraded sewage treatment works was instigated to reduce emissions, and industries have been prevailed upon to reduce organic pollution from industrial effluent discharges using “end-of-pipe” solutions. Many of the gross pollution issues have now been addressed, and we are now faced with greater challenges: Sustainability and Climate Change.
These two long term environmental driving forces, sustainability and climate change which are inexorably linked and cover a wide range of issues, are having a major impact on the way we think about our future on the planet. As a result we are approaching technology and management issues in new ways, but not least in water, waste and waste water.
Waste minimisation
The concept of the efficient use of resources, process optimisation and the minimisation of waste is not new, but it is now a mainstream objective of many companies. Not only because pollution costs money, and fines can result in a damaged reputation, but valuable savings can be made by reducing the resources used to produce the same number of products. Further benefits can arise by reducing their environmental impact in the long term, over their full life cycle.
Waste Minimisation procedures have been developed in the USA, Holland and elsewhere and are now being implemented world-wide. One of the most effective ways to get companies to focus on resource efficiency, is to bring them together in a “club”, mediated by experts, so that they can share their ideas and approaches. Perhaps the first “club” was the PRISMA Waste Minimisation project which involved 12 companies in the Netherlands between 1989 and 1991.
The approach is similar in nature to the establishment of an Environmental Management System (ISO 14001), involving champions and teams of staff working to targets set after each cycle of assessment. A number of similar demonstration projects were subsequently funded by the DTI in the UK including the establishment of the Aire & Calder Project which involved 11 companies from the chemical, drinks/beverage, printing and rail industries. More than £300,000 was contributed by the Government, Yorkshire Water and the BOC Foundation, on top of £100,000 contributed by the companies.
It has been estimated that £2.2 million savings were achieved initially with a potential for a further £2.1 million savings over the following two years as a result of good housekeeping and operational improvements.
Subsequent projects focused on key sectors such as the Food Industry, and the first of its kind was the SET Project which involved five food companies in Scotland, keen to share ideas and solutions2. The project cost each participating company £3,000 and resulted in annual savings of £1.17m, primarily in the wastewater area (see Figure 1). One key feature of this programme was the extent to which new technology and biotechnology in particular, could be used to secure savings in manufacturing, as well as water and wastewater treatment.
This experience was subsequently embodied in programmes in the UK such as Biowise and later Envirowise. These initiatives provided a pool of government funded experts able to help industry make their own savings as well as a range of useful publications which are still current. Such publications have been used as far away as China.
In 2003, a Waste Minimisation Club was started in Tianjin China, based on principles established using the UK “club” approach. Funded by the EU as part their Environmental Management Co-operation Programme (EMCP), the Tianjin Waste Minimisation Club identified more than ¥8.8m (£800,000) in annual savings in fuel, water, electricity, raw materials as well as waste and effluent treatment costs (see Figure 2). In a rapidly growing country, such as China, which earlier this year overtook the US in consuming most of the earth’s resources, principles of waste minimisation could be significant3.
By 2020 China is likely to need 250% of the energy it consumed in 2000. Any effort to minimise use of energy could have a significant impact globally.
The principles of waste minimisation may seem like “old hat” to many people, but the number of waste minimisation clubs has boomed in recent years, and at the time of writing the UK Envirowise programme is accepting applications to run new Waste Minimisation Clubs which will receive government funding, over the next three years, although they now prefer to refer to these as “resource efficiency” clubs.
One of the main findings throughout all of these projects is that in order to effect savings it is important to have all the necessary information available. “If you can’t measure it, you can’t manage it” is the old adage, but if you can not measure it you can not report it either. Sometimes information is available but it is not being used, or no-one knows it is there, or more frequently, it is simply not being measured. Programmes such as this are now leading to a boom in monitoring and analysis equipment needed to make the savings in water, wastewater, fuel, energy etc.
Integrated Pollution Prevention and Control (IPPC) and MCERTs
Waste Minimisation is no longer a voluntary activity in Europe, however, as it is mandated under the IPPC Directive. Targeted at most key industries above a certain threshold, the Integrated Pollution Prevention and Control Directive dictates what processes a particular industry can use, what industrial benchmarks must be maintained and mandates the use of “Best Available Techniques” (BAT).
The IPPC Directive also requires the implementation of an environmental management system, a waste minimisation programme, as well as an environmental assessment for the site and a complex monitoring programme. As an EU Directive, this must be in place Europe-wide by 30th October 2007, although much of the “new” Europe has a derogation on this for a few more years 4 .
No longer can someone make a product according to their own process without permission from the state. The technologies used and the way they are implemented must be the “best available”, and covered in BAT guides issued by the EU. Any new processes must be argued to be better than these, and all the processes must be resource efficient using as little water/fuel as possible. The overall process must operate within given industrial benchmarks and the appropriate measurements must be undertaken to demonstrate this.
The establishment of benchmarks (how many litres of water can be used to produce one litre of beer, for example) will result in improvements in water use and effluent generation and their increased regulation. As a result manufacturers are already actively seeking new technologies and processes which can save them water and electricity. This includes mainstream processes as well as water and effluent treatment systems.
Increased monitoring is not sufficient, however, the equipment must provide accurate and reliable data. New certification procedures, MCERTs, developed by the UKs Environment Agency largely to address IPPC industrial performance issues, are designed to ensure that not only is the right monitoring equipment used but that it is installed and operated correctly and that the subsequent data is accurate and reproducible. This ambitious programme suffers from lack of certified equipment and has been very slow to get off the ground.
So far the programme, implemented by SIRA (www.sira.co.uk), has largely focused on emissions to air. This is one of the key areas which certification addresses (Continuous Emissions Monitoring Systems – CEMS; Continuous ambient air Monitoring Systems – CAMS; Continuous Water Monitoring Equipment – CWMS). The measurement of effluent flow is mandatory under an IPPC permit, for example, but there are only three flow meters which are currently certified under MCERTs (two from Siemens and one GE) all are ultrasonic and understood to be for open channel flow. Although there are many more in the pipeline.
The EU has not been slow to make the most of these positive experiences as part of its aid programme, and has provided assistance to the accession countries to implement waste minimisation and environmental improvement programmes as preparation for IPPC.
Water savings technology
Developing countries such as China and India are not only hungry for fuel but also water. 63% of China’s urban households were connected to piped water supplies in 1995 and this is projected to rise to 85% by 2025. It is a similar story in India where connection to water is expected to rise from 11% to 47% over the same period. Considering the populations involved, this heralding a significant increase in water demand. Based on current projections water consumption in India will rise to twice that of the US by 2025 (to 400km3/y).
Apart from energy, water is a key resource which is a matter of life and death in many parts of the world. Another area where changes in our thinking about environmental problems are having a real impact is on reducing water consumption. It has often been said that after oil, the rush for new water resources is likely to be the next source of global conflict. This is somewhat ironic since climate change projections indicate that the sea water level is likely to rise by many metres.
Water Companies across the UK and Europe have been scrambling to reduce water leakage rates as well as installing more water meters in order to control water use more rigorously, and save this precious resource. The water industry has been actively seeking to implement sophisticated management techniques for water storage, treatment and distribution for some time5.
New technologies are also being sought across industry to reduce industrial benchmarks so that the amount of water needed for each tonne of product is as low as possible. The use of grey water, possibly untreated borehole water, rainwater or effluent after treatment, is another area which is actively being developed industrially for non potable applications such as washing lorries or non critical equipment.
One novel approach has been developed by a new UK university spin off Poseidon Water Limited. They have developed a system where toilets can be flushed with seawater resulting in dramatic savings in potable demands. Between one third and one half of water consumed per person is used for flushing toilets. The added cost is the need for two water supplies, one potable and one seawater, but if undertaken during the construction of a hotel near the coast, or for a new housing development, the costs are likely to be incremental.
This is not new in itself and seawater has been used for flushing toilets before, but using seawater results in a domestic effluent which is high in salt content and is difficult to treat biologically. Historically, wastewater from seawater flushed toilets has been directly discharged to sea.
Poseidon have developed a biological treatment system which is tolerant to higher salt content and can still treat domestic wastewater flushed with sea water. Such treatment systems can be installed in the basements of hotels or as local sewage treatment works. Considering that the 70% of the world’s proportion lives within 50km of the coast this could have a major impact.
Biogas production
The production of biogas from wastes and industrial effluents is also not new. In many developing countries, the quality of life is significantly improved by generating a cooking gas from waste materials rather than collecting firewood each day. In Europe and the West, biogas has been generated from digestion processes used to stabilise sewage sludge since the beginning of the last century7. Although often not used as a fuel, biogas was used at the end of the 19th century to light streets in Exeter, UK.
In Europe, the latest trend has been to develop centralised biogas plants for the production of a renewable energy from a number of industrial and domestic wastes, and effluents. This has been very successful, and in countries such as Denmark the energy is used for communal heating systems and for the production of Electricity. In Germany, the market has expanded dramatically with government support which has included subsidised electricity rates, low cost loans, and substantial grants.
This has led to a boom in the industry with a number of biogas companies being quoted on the stock exchange. In the UK, support for biogas has been much more limited, with general support for renewable energy technologies but no recognition that different technologies are at different stages of development and require different kinds of investment. As a result, only one of the governments projected 9-10 centralised biogas schemes has been built at Holsworthy, Devon, (see Figure 3) and this has already had a chequered history7. Ironically, this system was constructed by a German company which initially flourished as a result of the subsidies there.
With Global Warming as a new driving force, the emphasis is now on mitigating emissions of methane to the atmosphere from existing treatment lagoons and other systems. Methane is 23 times more potent than carbon dioxide as a greenhouse gas and for every tonne saved there is the potential to secure a tradable certificate of emissions reduction (CER) worth 23 tonnes of carbon dioxide (each CER arguably worth $5 or more per tonne of CO2 saved).
Under the Kyoto Protocol emissions reductions in developing nations can be purchased by developed countries as a way to cost effectively reduce their obligation to reduce carbon emissions. Since many developing countries are in warm climates where methane is readily generated, anaerobic digestion is an ideal technology to mitigate emissions and to capture the biogas for the production of a renewable energy. Developed nations are keen to buy CERs to offset difficult targets which much be achieved at home.
Opportunities in countries such as Mexico, for example, are significant6. In a recent study funded by the UK FCO (Foreign and Commonwealth Office) significant opportunities were identified for cattle, pig and agro-industrial operations in Mexico (see Figure 4). To benefit from Emissions trading opportunities however, each developing country must have a host nation office and a local infrastructure to certify emissions saved. These are now more prevalent and where they are not established many countries are in the process of doing so.
Although it is early days for CER trading so far, companies are already signing up potential clients in developing countries. Often the climate is naturally warm and with an appropriate low cost technology based on covered lagoons lined with flexible liner materials such as HDPE (high density polyethylene), digesters can be deployed to treat many agro-industrial wastes.
In Asia, one organisation in particular, the Asia BioGas Company, is spearheading its own quiet revolution and has constructed nearly 50 anaerobic digesters in the last 4-5 years on animal and industrial wastewaters. One of these, based on a Cassava factory is thought the be the largest digester in the world (100m x 100m x 10m deep) and can generate 12MWe of electricity or fuel to run boilers on site (see Figure 5) 6
Conclusion
Environmental challenges are here to stay and are arguably more important than ever. New approaches, systems and technologies are being developed to help reduce our environmental impact but in the long term a true sustainability must result from zero growth and the development of a dynamic balance between man and the natural world.
References
1 Keeping the lights on: nuclear, renewables, and climate change, HC 584, Sixth Report of the House of Commons Environmental Audit Committee for the 2005-6 Session, United Kingdom Parliament, 16th April 2006, The Stationery Office Limited. www.publications.parliament.uk/pa/cm200506/ cmselect/cmenvaud/584/584i.pdf
2 Etheridge, S. P. Biotechnology & Waste Minimisation – the Natural Link, Envirotec, Issue 6, 4, pp 35, Peebles Publishing Group Limited, December/ January 1997.
3 Brown, L. R., A New World Order: Special Report China, The Guardian, 25th January 2006.
4 Etheridge, S. P., Keynote Address: IPPC in Pre-Accession Countries, in Delivering IPPC 2003, Institution of Chemical Engineers, 4-5 November 2003, Dunchurch Hall, Rugby.
5 Etheridge, S. P. et. al., Report and Opinion on the Widescale Adoption of Lower Cost New Technologies and Practices in the Water Industry, Babtie Environmental Limited, for OFWAT, May 1994.
6 Antonioli D., Etheridge S. P. and Poch A., Assessment of the Potential for Developing Electricity Generation and Clean Development Mechanism Projects in the Animal Manure Management Sector in Mexico, Project Reference No. PGI GCC 000087, Global Opportunities Fund, UK Foreign and Commonwealth Office, 26th August 2005.
7 Etheridge, S.P., International Best Practice Guide for Anaerobic Digestion, United Nations Programme CPR/97/G31 UNICA No.1109, October 2003.
8 Industrial Wastewater and Effluent Treatment: A Review of Anaerobic Digestion Technology, DTI BioWise Programme, 2001 (authors include Etheridge S.P.)
Published: 10th Jun 2006 in AWE International
