Saeefar Rehman, associate director, energy and environment for Grant Thornton UK, looks at the future of landfills and wonders whether their future primarily lies in becoming a key supplier of energy?
The collection and disposal of waste to land, generally without any treatment, was the bedrock of waste management until the early part of this century. Legislation and social change provided a very clear message… treatment of waste was going to be needed landfilling was no longer an option.
For many, the term “landfill operator” became a marketing nightmare. Firms and operators repositioned themselves as “recovery” specialists, some even leaving their brand names behind due to the connotations that they held in the industry.
Despite all this, landfills will remain relevant and continue to have a role to play, at least in the near future. For one thing there is no treatment option that does not leave something that needs to be dealt with at the end of the process. With thermal treatment being employed in the treatment cycle, both inert and toxic residues have to be dealt with. For example, in relation to energy from waste, although bottom ash recycling and reuse is on the rise, the same is not currently true for fly ash, although a viable solution is likely to be introduced in the near future.
Persevering With Landfill
Some operators persevered with the landfill market but the wide range of gate fees charged by different operators are an indication of the different stresses borne in different parts of the country, both as a function of the underlying costs and the local market. Gate fees have ranged from as low as £10 per tonne, to as much as £55 per tonne, as per recent WRAP reports. Such perseverance cannot last beyond the short to medium-term, as treatment of waste is now the only realistic long-term option due to forthcoming landfill bans and restrictions in parts of the UK and the risk of similar action in other parts.
Also landfills do not just disappear; they require maintenance and management, which have an on-going impact on landfill operators balance sheets and P&Ls. Therefore any value that can offset on-going costs is important. So what opportunities are there in recovering value from landfill?
There are two main aspects, material recovery and energy recovery, with the status of the landfill having a major impact on the viability and risks of any recovery. Capped landfills and currently active landfills present different challenges and opportunities.
The obvious question has been whether the material in landfills can be recovered. Landfill mining and reclamation (LFMR) is not a new concept and has been around for at least 60 years. It is something that has also already been exploited on ex-colliery spoil heaps, where before coal-fired powers stations existed that took fine material, any coal not in lumps was not considered worth selling. For a time, this left a valuable resource to be exploited. As is usually the case, it is the financial viability of a project that determines whether it is implemented. The recovery of obviously precious materials, like metals, is something that has always been considered but the equation is the same for all materials. Economics… supply and demand… price. As prices for materials increase, it would become economically viable to recover materials from landfills.
The second aspect is energy recovery. Landfills in the UK could become sources of energy in the next 20 years. There is already a move globally to capture landfill methane gas and the applications range from generating energy to using it as vehicle fuel. As technology improves, including around landfill management, the landfill sites that were once the only solution to the waste problem, then a problem for the environment, may become a source of reliable energy in the future.