Standard for producing renewable energy and fertiliser revised

12 September 2014

BSI, the business standards company has revised PAS 110 Specification for whole digestate, separated liquor and separated fibre derived from the anaerobic digestion of source-segregated biodegradable materials to help further enhance the development of Anaerobic Digestion (AD) systems. Anaerobic digestion is a valuable process which enables renewable energy and fertiliser resources to be made available as products from biodegradable materials. 

This process is seen as one of the key ways in which organizations can increase their ‘green’ credentials and is widely used to treat wastewater, domestic and commercial organic wastes and manures. The benefits of anaerobic digestion are many including the option of diverting waste away  from landfill subsequently reducing greenhouse gases from escaping into the atmosphere.

Sponsored by WRAP (Waste & Resources Action Programme) PAS 110 helps to remove the major barriers to developing AD systems. It provides an industry specification against which producers can verify that their material is of consistent quality and fit for purpose. The specification covers all AD systems that accept source-segregated biowastes and produce biofertiliser - namely whole digestate, separated liquor and separated fibre. 

What PAS 110 specifies:

  • Controls on input materials and the required validation process for initial PAS 110 certification
  • Minimum quality of whole digestate, separated fibre and separated liquor
  • Information that is required to be supplied to the digestate recipient

Beyond the operators of Anaerobic Digestion facilities, PAS 110 will be of benefit to Consultants, Environmental Regulators, Trade Associations and the wider agricultural, land reclamation and horticultural sector.

Key changes to PAS 110 include:

  • Amended  threshold limit for stability 
  • Amended threshold limits for physical contaminants 
  • Amended pasteurization requirements for non-ABP (animal by-products ) feedstocks
  • Amended PTE (Potentially Toxic Elements) threshold limits

David Fatscher Head of Market Development for Sustainability at BSI said: “Having a specification which gives confidence to both digestate producers and the market they supply is vital. As such we need to be supporting all the possible mechanisms that enable biodegradable wastes to be treated in a way which maximizes the possible benefits. This includes limiting harmful gases from landfill. PAS 110 helps to achieve this by directly contributing to a safe, sustainable and profitable AD industry.” 

Some of the organizations involved in the revision of PAS 110 include experts such as: Anaerobic Digestion Operators Working Group, Anaerobic Digestion & Biogas Association, Chartered Institution of Wastes Management, Environment Agency, Natural Resources Wales, Renewable Energy Association and Waste & Resources Action Programme.

Ian Wardle, Head of Food Resource Management at WRAP, said: “With the increasing need to deliver sustainable markets for digestate, WRAP has worked closely with the other PAS 110 steering group members to ensure that the revised specification continues to deliver a safe, quality-driven product.”