Proceedings

Agricultural recycling of sewage sludge is considered the Best Practicable Environmental Option (BPEO) in most circumstances by the UK government and Europe. However, sludge cake does not have a universal appeal to the farming community due to certain limitations such as logistical problems, agronomic issues and environmental concerns.  Its application is also highly regulated.

United Utilities and Cranfield University through a Knowledge Transfer Partnerships have developed a novel method for agricultural application of sewage sludge known as Organo Mineral Fertilisers (OMF). These nutrient–enriched products are characterised by improved physical and chemical properties, designed to address many of the limitations of sludge recycling. Crop responses and yield potentials of OMF products have been proven by various studies conducted at Cranfield University over the last two years.

To understand the use of the OMF products in general farming practices, farm-scale crop trials have been established at Broxton, Cheshire in association with Harper Adams University College. These trials aim to demonstrate the yield potentials of OMF compared to conventional mineral fertilisers when used according to “good agricultural practices”. These trials are also looking at the possible accumulation phosphorus (P₂O₅) and heavy metals on the soil at various fertiliser application rates. The four most popular crops in the area have been selected for the trials, namely Winter wheat, spring Oil Seed Rape, Maize and Rye grass which have been grown on 1.6ha of land in strips (24m x 144m). Both fertiliser treatments are aiming to provide a similar nitrogen application rate on selected crops. Each fertiliser treatment with six replicates for each crops have been laid out in randomised complete block design.

All the analysis including soil analysis and crops yield measurements will be completed by September 2009 and the results will be presented in the full paper.