Sort Line Guidance: Advice For Processors Of Recyclable Materials

This guide was produced to help local government decision-makers and operations managers to decide whether their authority will operate a facility to separate materials in-house (by constructing a sort line) or to sort recyclates via a third party.

Our detailed forecasting of costs and incomes is helping them to select the most cost-effective and practical option that also delivers the best social impact.

The guide includes several suggested systems to give the reader an indication of how a system might look when it has been configured and provides enough information to help them manage a construction project with the help of an experienced engineering contractor. We also provided a suggested timeline and costs schedule including advice on procurement, building and commissioning.


Zero Waste Scotland commissioned Resource Futures to produce guidance for local authorities on the post-collection material sorting infrastructure required for various material streams, aligned with the Household Recycling Charter Code of Practice.

The guidance needed to be suitable for use by Zero Waste Scotland, Local Authorities and others who wish to appraise the impacts of aligning their waste services with the Code of Practice.


In order to understand the most important factors to be considered, interviews and site visits were carried out across the UK, with sort line engineers and operators as well as local authority officers and technology providers.

Detailed information was collected on the costs of purchasing and installing capital equipment, as well as operations and the value gained as income from materials.

The guide was divided into four sections:

  1. Describes the composition of material which requires sorting – a defining feature of any system which is then implemented, which affects the material market values and thus the overall business case.
  2. Describes in detail the different approaches to developing a material sort line, including an overview of the commonly used equipment, equipment configurations, human resources, storage and safety considerations.
  3. Summarises the alternatives to developing an in-house sorting system (i.e. using third party sorting facilities) and considers the implications of doing so.
  4. Compares the relative costs of the options for local authorities processing different quantities of materials. The guidance provides examples to cover the majority of different authority sizes and types.


In preparing this guidance our estimates have indicated that larger facilities tend to be more cost-effective in the long-term than smaller plants due to economies of scale. The critical factor for authorities deciding whether to construct a sort line, and especially for mixed papers, is to ensure that the risk of market downturn has been properly accounted for.

By using the guidance decision-makers can make informed choices about how to proceed effectively. Improved material quality can increase income from material sales and thus help improve resilience against market uncertainty in the global recyclate markets.

Project Information

Services involved

Material Processing and Markets

Team involved

Bethan Jones

Sally Scholefield
Senior Consultant / Designer