Over 44m3 of Leca Lightweight Aggregate was pneumatically delivered to cover a Bio-Gas Digestate Lagoon in Wrexham for Fre-energy. Leca LWA is recommended in its official guide for waste management by DEFRA (Department for Environment, Food & Rural Affairs) to be a solution to provide harmful gas abatement into the local environment, including Ammonia, which poses a significant threat in areas of valuable habitats.
‘Covering slurry stores is an effective method for reducing ammonia emissions and is a requirement for all new storage facilities on installations covered by IPPC. Results from recent research indicate that, in addition to specially engineered covers, potentially cheaper covers such as a floating layer of LECA (light expanded clay aggregate).’ – DEFRA (Department for Environment, Food & Rural Affairs)
Fre-energy in Wrexham is a major innovator in waste management in the UK and one of its major features is Lodge Farm Biogas Ltds Anaerobic Digester. Operating as an efficient slurry and food waste management system, their patented combined de-gritting and gas actuated mixing technology is designed to manage grit laden, high-strength wastes and slurries. The main aim of Lodge Farm Biogas AD is to assist local food manufacturers deal with process waste in an eco-friendly way. The lagoon was constructed to handle the digestate produced after the AD process. A valuable, natural fertiliser, digestate is by process virtually inert (most of gases converted to biogas by anaerobic digestion) and odourless. The application of Leca LWA serves to meet regulatory compliance by handling the residual ammonia that would otherwise be released to atmosphere.
Environmental regulations set by DEFRA ensures that the levels of harmful gas released from waste management processes must be reduced to a minimum – Leca LWAs unique properties prevents harmful gases into the surrounding countryside – potentially causing damage and pollution to the local area. These initiatives, and targets set by government to reduce gas emissions (including ammonia) and the removal of foul odours of slurry tanks is a major challenge for many farmers.
A quick and simple solution is to pour Leca® Agri directly on top of the slurry, which acts as an effective floating protective cover for a slurry tank or lagoon. A 10cm layer of Leca® Agri poured over slurry limits the emission of harmful gases and foul odours by up to 85%. The Leca® Agri floating cover solution is designed for reducing gas emissions (mostly ammonia) from liquid animal waste and complies with EU standards and BAT guidelines (Best Available Techniques) and may be used on a par with closed tanks. Conversely the Leca LWA provided a protective layer to keep the nutrients generated by the farm within the slurry.
Lodge Farm Biogas Site Manager, Tom said that…..”The material did exactly what we required and this was to provide an effective cover for our lagoon with the aim of reducing the amount of ammonia released into the surrounding area. The material was quickly blown onto site with the Leca blowing machine with no issues and quickly covered the lagoon which is over 1200m2 in size. This operation took only a few hours to complete. The floating nature of the material quickly provided a floating cover for the slurry pit.
“The time saving solution provided by Leca LWA was key performance indicator for us, we needed to find a product which would effectively reduce emissions of Ammonia and provide a protective layer for keeping the nutrients within the slurry in our farms.”
Download our guide on Leca Agri