With environmental concerns coming to the fore, recycling waste is an increasingly attractive option, but for many, the major draw of recycling is simply to reduce costs. “If you keep on sending waste to landfill then you are burying money,” says Steve Burnett, managing director of Compact&Bale. “Although the costs of disposing of waste do vary according to the method used, throwing waste away can cost you as much as £50-100 a tonne and typically, the less waste you have the more expensive it is to dispose of.”
Compact&Bale offers a comprehensive range of waste solutions to a wide range of concerns, including shopping centres and manufacturers, and has formed a strong presence in the produce industry. “We will buy the cardboard off you and in many cases we will also dispose of it for you,” says Burnett. “There are a lot of companies that deal with equipment, and many that recycle but few do both. It helps that we are able to put together a tailor-made package for our clients and from a produce point of view we are able to deal with materials that other companies would not be able to work with, including pvc trays and punnets.”
The Kent-based company works with the DURApac range of compacters and balers. “Waste ends up either in mills or in processors. We do tend to work with one mill in Kent - around 95 per cent of our material goes there because 90 per cent of our jobs are within striking distance of Kent, but if it is more convenient then we go to other mills in the UK.”
The produce industry is fairly clued up as to the benefits of recycling, says Burnett, but there are always some companies that are not receptive to the idea. “Businesses that are affiliated with farms and agriculture have traditionally been used to burning their waste but regulations surrounding that changed last year and so interest has gradually risen there.”
When companies do decide to change the way they handle waste, the first thing they should do is to ensure the company is a licensed carrier, Burnett continues. “There are some very good companies out there but across the entire waste management sector there is a lot of fly-tipping that goes on - it is the underbelly of the business. It is a risk that all companies should guard against. Everyone has a duty of care to containerise and to handle waste properly and make sure people who dispose of it are certified. That is where we can help - we are here to give advice and we will always do what we can.”
Manchester City Council is rising to the challenge of how to recycle more and landfill less with the implementation of the New Smithfield Market’s Waste Management Plan. At the UK’s largest northern wholesale market, a 2002 waste audit revealed that New Smithfield produced 5,500t of mostly organic waste that was being transported outside of Manchester for disposal via landfill. Ninety-three per cent of that waste was made up of fruit and vegetable waste and cardboard and all waste from the market was taken by road to landfill sites in Cheshire and Yorkshire. The audit also revealed there was great potential to reduce the amount of land being landfilled by composting the organic material.
Due to the immense scale of the project Manchester Markets then entered into a unique partnership with local community recycling business, Fairfield Materials Management, which developed a pioneering waste management plan for the market working on three levels: by reducing the amount of waste generated, recycling as much as possible and by composting the remainder.
Although the waste management system offers a holistic approach to the various aspects of waste - from persuading businesses to change the materials they use to recycling cardboard, paper and plastic - at the heart of the system is the composting of organic materials, made possible by the provision of a Vertical Composting Unit (VCU).
Specially made in New Zealand, a VCU takes a mixture of organic and cardboard waste from the market and carbon (woody) waste - initially supplied by the City’s parks. The additional green waste required with the expansion of the system will be diverted from a new household green waste scheme that was piloted in autumn 2003. Various recipes are used with differing amounts of cardboard and carbon being added depending upon what is being composted.
The unit is low maintenance, has a low labour requirement and uses low amounts of energy. The temperature in the unit exceeds 70°C - the temperature required to meet EU standards. All material is odour-stabilised and pathogen free. Material is in the VCU for seven days and after a further four to six weeks of storage outside the VCU the compost is ready.
This system represents a quantum leap forward in the market’s waste management plan, changing a situation where nothing is recycled to aiming for zero-waste from the market by 2008. It will also bring a multitude of benefits. When organic waste is disposed of in landfill it produces greenhouse gases, most prominently methane. In the VCU the aerobic composting process produces no methane. All EU countries are under an obligation outlined in the EU landfill directive to reduce greenhouse gas emissions from such sources by 2020, with the UK having to reduce the quantities of municipal waste going to landfill by up to 50 per cent of the total produced in 1995. In addition it will also help reduce the city council’s 250,000t of landfill that costs £10 million in charges a year, savings that will be passed onto Manchester residents through improved services and lower council tax rises. It also helps market traders to reach recycling targets.
The advantages of composting over landfill are countless. The material is processed locally and the benefits are returned to the local area. Composting needs to work at a local area because at a larger scale the benefits are diluted by increased transport costs and emissions. The composting process reduces the waste’s volume by 35 per cent, and as the compost is being used in the local area the transport costs and pollution are kept to a minimum. The rich compost helps reinvigorate poor soils - giving them better structure, nutrient content, productivity and water retention and makes them ideal for reclaiming brownfield sites.
Initially, Fairfield trialed the process with four wholesalers. Samples were regularly sent to analysts D&F Associates, with good results. “On initial evaluation, Fairfield’s compost passes 100 testing standards and results indicate that this material is safe to the environment,” says D&F Associates’ Sandra Davies.
Initially the compost was solely used by the city council in its parks. It will eventually replace peat as a soil conditioner, and so protect vulnerable peat bogs. One drawback with composting is that it produces large amounts of bulky material that soon builds up if not removed, so finding a market for the end product is essential. But as production has increased, awareness and demand for local sustainable compost has grown beyond expectation among local householders, allotment societies, topsoil companies, and landscapers and money made from the sale of compost is immediately re-invested in the project. A market has been created where there was none before, using material that was previously discarded.
The waste management programme has been planned in three distinct phases. Phase one was the trial of one VCU with four traders. The next stage saw two more VCUs installed on site and 12 traders involved in phase two.
This will process half of the waste stream and divert 3,600t of waste that would have gone to landfill into 2,500t of nutrient-rich compost every year.
The third and final phase will allow for the purchase of a further three VCUs, resulting in full capacity being reached at the market. Five and a half thousand tonnes of waste will be diverted away from landfill and made into 4,875t of high quality compost. Eighty-eight per cent of the market’s biodegradable waste will be processed. Three thousand tonnes of household green waste that was previously land filled will also be used from 2005. Alternative uses for quality fruit and vegetables are being investigated, and with cardboard recycling this will account for the remaining 12 per cent of biodegradable material in the waste stream.
The end result will be the realisation of the zero waste target for New Smithfield Market by 2008, making it the first wholesale market in Europe to achieve this. When the system is fully operational a blueprint guide will be produced for others to follow. Already the system has generated huge amounts of interest within the wholesale market network, and is viewed as a beacon project with interested parties from New Covent Garden visiting the site to see how the technology at Smithfield could be used for their own waste-management programmes. The guide will assist other markets and groups to follow a system that works and delivers results.
As word has spread, demand from the private sector has also grown and the integrity of the project was recognised in 2003 when the Composting Association awarded it Best Community Initiative in 2003. Councillor Paul Murphy, executive member for Direct Services, says: “This award is very well deserved by Fairfield; its hard work and vision in partnership with Manchester markets deserves to be applauded. In creating a commercially viable and high-quality end produce from what would otherwise have been thrown away, they are leading the way in environmental sustainability.”
The management of Glasgow Wholesale Markets has selected HotRot in-vessel composting units to process organic waste from the fruit, vegetable, fish and poultry markets. The intention is to produce quality horticultural compost from waste generated on the site in the Blochairn district of Glasgow and the resulting compost also has the potential to provide a useful revenue stream.
Graham Wallace, Glasgow city council’s market manager, says: “We are assisting Glasgow in reaching its recycling targets and we are fulfilling our own commitment to best practice. The HotRot system was selected because it is an operationally simple, compact and cost-effective solution to the problem of mounting waste disposal costs. We see compost production as compatible with our core business - fresh produce comes in from the growers and compost can be returned to them.”
Glasgow City Council has demonstrated its commitment to sustainable objectives with this initiative. It has identified the facility’s ability to divert a significant waste stream from their landfill site, reduce the lorry movements from the market, avoid the increasing costs of disposal to landfill, cap costs and generate savings for the market.
Ron Gilchrist, HotRot’s Scottish Agent, explains: “We are particularly pleased that HotRot has been chosen for Blochairn as it is located close to communication routes and Glasgow Council are happy for it to serve as a flagship project which can be seen [by arrangement] by parties interested in this innovative technology. Judging by the interest shown in the HotRot unit we exhibited at the Institute of Waste Management Exhibition in Torbay, last month, we expect the Glasgow Market’s composting plant to receive many visitors, not just from the city but also from around the UK.”
HotRot will supply two model 1811 composting units aligned in series to satisfy the requirements of the UK Animal By-Products Regulations (ABPR). A minimum temperature of 60°C for two days will be attained in each barrier, which facilitates pasteurisation of the waste and will kill most weed seeds. A microprocessor controls the operation of the process and the moisture content of the mix. The innovative design ensures low operating and maintenance costs. A further feature of the installation will be a shredder, which will split plastic wrapped produce to ensure complete composting in the 16 to 20 day residence time. Pasteurised waste plastics will be removed by screening the product after processing. Odours will be controlled by a HotRot bio-filter and, as no liquid effluent or leachate is produced, the HotRot system is environmentally friendly.
In-vessel composting is an ideal process for organic waste recycling. Composting, in the form of heaps at the bottom of the garden or out in a field, has been around forever but the results are often disappointing as the process is complex and dependent on the skill of the operator. The material has to be turned regularly and can easily become too wet, too cold or too dry. During the turning operation, dust generation can be a problem. The process tends to be inconsistent and the quality of the product variable. The advantage of the HotRot system is that it addresses these limitations. Once the waste is loaded into the Feed Unit, the process is automatic. Optimum conditions are maintained within the chamber and consistent product quality is achieved.
The benefits of returning humus, carbon and minerals to the soil are well known - reversing the trend in modern agricultural practices which mines these key components from our fields and gardens with consequential affects on both plant vigour and the quality and value of fresh produce crops.
Composting not only recycles essential elements but also improves the texture of the soil. Incorporating compost into the soil helps to retain moisture, reduce flash flooding and reduce fertiliser run-off. The crops are stronger, require fewer pesticides, and the food crop is heavier and more nutritious.
The alternative disposal route of landfilling organic wastes can produce large quantities of methane, which is 20 times more damaging in terms of climate change than CO2. Methane is generated whenever anaerobic conditions occur. The biomass in modern in-vessel composting systems is agitated many times every hour - the chambers are ventilated - anaerobic conditions cannot occur - methane cannot form.
HotRot is the latest technology in a long line of improvements on the garden compost heap. Outdoor windrowing can have a lower capital cost but cannot conform to the Animal By-Products Regulations [ABPR] requirements. It can also suffer from nasty odours, leachate and vectors such as flies, seagulls and rats. To overcome several of the windrow deficiencies, enclosed static piles were developed, some of which have air injection to improve composting efficiency. However, there is no mixing in the vessel and so poor product uniformity can occur. Several attempts to improve on static pile technology have been introduced in recent times by incorporating cages and moving trays, vertical flow-through columns and rotating drums. Each has advantages - but often at the cost of mechanical complexity and increased operating and maintenance cost. In some systems the material is handled two or three times as it is moved from one vessel to another to meet the ABPR requirements.
The New Zealand developers of HotRot believe they have addressed all these problems. The units can sit outdoors, minimising buildings requirements and it is a continuous process with no double handling. As soon as the waste is generated, it can be loaded in at one end of the plant and the compost discharges from the other. It is mechanically simple yet provides good mixing, sufficient aeration and balanced moisture control - the essentials for efficient composting. There is only one major moving part - a strong central shaft fitted with mixing/aerating tines. The HotRot computer controls all this, along with the feed unit, the product screen and the bio-filter. Above all HotRot is a continuous process whose control system ensures minimal operator intervention.
There are no cost or capacity penalties when aligned in ABPR formation and capacity can be increased by modular additions. These increments range from one to 12t a day. The units are quiet, have a small footprint and a low profile. The weight reduction in the process can be from 50 per cent to 80 per cent, depending on the composition of the waste.
Glasgow Markets is also using composting to recover damaged and date lapsed produce. Shredded cardboard, paper and damaged pallets will be used to balance the moisture content. In-vessel composting technology can be used for recycling supermarket organic waste, again making use of the ability to compost partially-wrapped produce. Modern pre-treatment shredders can break up wood, split cans and gently open shrink-wrapped fruit and vegetables.
Further along the food production chain, farmers and commercial growers can use composting to recycle and pasteurise waste on-site. Poultry and animal offal can also be safely composted in these enclosed units by blending with green and other high carbon bulking agents. Waste from kitchens, food preparation and processing plants makes ideal feedstock for compost production and the technology also has an application in treating sludge from sewage treatment plants. If it is organic, there is a fair chance that it can be composted in a HotRot in-vessel composting unit.
SCA’S PAPER WEIGHT
SCA Packaging Industrial Division offers total packaging concepts to customers through functional and cost effective solutions taking into account environmental factors.
Conforming to current and known future environmental legislation, SCA Packaging Industrial Division has manufactured cases for industry for more than 25 years supported by the SCA Group Forest division, which manages two million hectares of productive forest land in Sweden. SCA plants 50m trees a year to ensure a sustainable supply while minimising the impact on the environment and recycle 2.4mt of recovered paper for integration back in to the paper manufacturing process.
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The manufactured corrugated cases are mono material, totally recyclable and can be collapsible for multi-trip requirements. These features generate large transit savings while maximising environmental benefits and helping customers meet waste legislation obligations.
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