Treatment & Technology

Remade Scotland have developed two models to assess the treatment capacity requirements in Scotland:

1. A MRF Modelling Tool - to establish facility requrements and costs.
2. An Anaerobic Digestion Model - to estimate biogas yield and
digestate output quantities and quality.

MRF Model

In 2008/09 Remade surveyed all Scottish Local Authorites to identify those Councils who were planning on switching to co-mingled collections. There are currently 8 fully co-mingled recyclate schemes in Scotland, while 11 Councils identified that they will or may move to full co-mingled schemes in the future. This would result in between 93,000 tonnes and 163,000 tonnes of additional MRF processing capacity in Scotland and require a capital investment of circa 10.4 million and the potential creation of 103 new jobs. The analysis and results are reported in our Short to Medium Term MRF Requirements in Scotland, soon to be available for download.

Activities for 2009/10
Following discussions with the Scottish Government and WRAP, Remade will further develop the MRF analysis to:

• Establish scenarios to identify the maximum tonnage of recoverable materials from kerbside collections
• Model these scenarios as comingled collections and evaluate the impact on recycling rates in the context of the 70% target
• Look at worldwide examples where sorting of "unconventional recyclate" (i.e. films, foils etc.) is taking place and the physical plant required to do so
• Establish the quantity and quality of facilities required in the six economic development regions required to sort this material for sale into commodity markets
• Evaluate the probable costs of delivering such facilities
• Asses the probable revenue potential of the recovered recyclate commodities
• Provide an outline cost per tonne for infrastructure delivery

Anaerobic Digestion Model

Remade Scotland will be seeking to develop further capability in accurately estimating the impact that anaerobic digestion of food waste and other digestible materials will have on the Scottish waste markets. We are also developing an anaerobic digestion model which will be used to develop regional scenarios of:

• Co digestion of municipal and commercial feedstocks
• Production and use of biogas
• Production and use of heat and power
• Production of useful digestate fertiliser

Linked to the Remade work on commercial and industrial waste, we will seek to estimate the quantity and quality of municipal and commercial feedstocks available in Scottish regions that may be available for anaerobic digestion. Further research on the properties of those materials will allow accurate modelling of biogas yields and digestate quantity and quality.

Production and use of digestate continues to be an aspect of anaerobic digestion that requires further research. In this work Remade will assess the key fertiliser properties of digestate (NPK) and how changes in the feedstocks can affect the quality of output material. Our modelling works will assess the quantity of digestate output in each region - the likely value of that material and what the markets may be for use including information on additional possible uses, such as elemental nutrient recovery, creation of fuel pellets, fish farming applications etc.