Waste: The Issues

Waste is defined as anything for which we no longer have a use and wish to discard. Waste costs businesses money: through the price paid for raw materials that are wasted, the costs of their subsequent collection and treatment by waste management operators, and finally through the amount paid as landfill tax. In addition to being a financial burden, waste is also a contributor to climate change, with the 4% of greenhouse gas emissions in the UK attributed to waste management operations, largely attributable to landfill emissions.

Choosing Waste Management Options

Opportunities for reducing expenditure in, and environmental impact from, waste management depends upon the characteristics of the waste and the options available for its management. The Waste Hierarchy and the Proximity Principle are two good starting points.

The Waste Hierarchy advises that, where ever possible, efforts should focus on first reducing waste, followed by re-use, recycling or composting, energy recovery and finally landfill in that order. The Proximity Principle suggests that waste should be treated as close to where it arises as possible.

Reduction may be possible and reviewing processes or carrying out a waste audit may highlight areas where over-ordering has become an issue. Alternatively, substitution such as replacing previously disposable items for reusable options, e.g. plastic crates for cardboard boxes, can help reduce the quantity of waste a business has to dispose of thus avoiding all the associated costs.

Recycling occurs when waste materials are used in the manufacture of new products and displace existing virgin raw materials. Because using recycled materials rather than raw materials can reduce manufacturing costs, some materials have a reasonable market value as recyclate; because of these materials’ inherent value, sending these waste streams for recycling rather than to landfill may therefore reduce expenditure on waste management.

Composting is nature’s way of recycling. Under controlled conditions, micro-organisms break down waste organic material (e.g. food waste) into an end-product that can be used as a soil conditioner for horticultural and agricultural purposes.

A variety of technologies exist that recover energy from waste, with the most commonly applied being anaerobic digestion and incineration. Energy can be recovered from organic material (e.g. food waste) through anaerobic digestion, which is another technology that harnesses natural microbial processes to break down organic matter and produce combustible gases, such as methane. The methane is then combusted to generate electricity and heat. The other common method of recovering energy from waste is through combustion in specially designed and regulated facilities.

Landfilling is the burial of waste in the ground in sites called landfills. Landfills are highly engineered facilities with complex liners to capture liquids and gases generated from the decomposing wastes. Some wastes are banned from landfills and, to encourage further diversion, since 1996 a tax has been applied in addition to standard waste management costs. This tax currently stands at £48 tonne landfilled, but is set to escalate at a rate of £8 tonne/year.

Greenhouse Gas Emissions from Different Waste Management Options

The table below (adapted from Defra guidance), broadly supports the waste hierarchy and shows typical greenhouse gas emissions associated with reducing waste (by avoiding the use of virgin raw materials) or sending various waste streams to different types of treatment. Associated GHG emissions are shown in tonnes CO2 equivalent per tonne of waste treated for individual material types. Used within the context of the Proximity Principle it will aid the selection of more environmentally waste treatment options.

Greenhouse Gas Emissions savings from various waste treatment options