Use of up flow anaerobic sludge blanket anaerobic digestion systems

This sets out the requirements that will allow you to use fast anaerobic digestion systems with a manure and slurry feedstock on farms without the need for an environmental permit.

This publication was withdrawn on

This regulatory position statement was reviewed in consultation with the industry trade bodies. We removed it as it was not being used.


The use of up flow anaerobic sludge blanket anaerobic digestion systems: RPS 125

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The Environmental Permitting Regulations (EPR) 2010 provides a waste exemption T24 for on-farm anaerobic digestion (AD) at premises used for agriculture and burning of resultant biogas. This exemption allows plant tissue waste and farm yard manures and slurries as feedstock to an AD plant.

One of the limits in the T24 exemption is that the feedstock must remain in the digester for a minimum of 28 days. Since fast AD is capable of producing stable digestate in a much shorter period of time, we will allow fast AD operations to benefit from the T24 exemption without needing to comply with the 28 day residence time if these requirements are followed.

Published 27 March 2014