Recycling End-of-Life Artificial Turf Fields

Photo: A machine called a DSC used for testing the yarn for polymer type.

There is much discussion in artificial turf circles about recycling end-of-life fields. In a nutshell, it is both difficult and expensive because of a significant lack of processing plants available in the right locations - ones that can easily cope with the potential demand. Funding is not targeting recycling as a priority. Many have begun to address these issues in Europe where there are facilities available and more being constructed. These facilities will provide an opportunity for used artificial turf to be broken down into reusable constituent components and made into new products.

Several barriers make recycling end-of-life turf undoubtedly difficult. Challenges include a lack of facilities that are capable of dealing with used turf. The lack of appropriate funding to kick start the wholescale use of recycling is another barrier. The availability of suitable outlets for the component constituents in some countries, along with the fact that disposal is still a cheap alternative to recycling, is another.

However, there are reasons to be positive and optimistic about the possibility of accessing recycling in the short-term. In the next 12 months, capacity will come on-stream to make recycling an achievable alternative to disposal once funding is in place.

The recycling journey really starts prior to the removal of the turf from the field. To make recycling used turf easier for recycling plants, it is desirable and sometimes necessary to fingerprint the used turf system. Sending multiple batches of used turf from different manufacturers with varying yarn types, varying performance infill types and varying grades of sand means that the chances of producing value-added components from the mixed batch is restricted. Indexing what is emanating from a site by way of yarn type, backing, rubber and sand is informative to a recycling plant and can mean the plant can make better use of the materials coming in from the various sites. Pre-removal testing of turf involves obtaining representative samples of the turf and infill. At the same time, it is possible to obtain the measurement of the depth of infill (sand and rubber crumb) and dimensions of the field so that accurate quantities can be determined.

Some testing that can be carried out on turf and infill, prior to the uplift and transport of the end-of-life turf is as follows:

Basic Carpet Identification Testing

• Pile length

• Dtex

• Number tufts

• Approx. pile mass based on above

• Condition of yarn heavily fibrillated

• Seams, number/spacing, condition

• Surface condition

• Lines- colours, condition

• Does the surface drain

• Any obvious issues or damage from drainage and flooding (may affect quality of sand recovery)

• Contamination from surroundings?

• Moss, weeds, etc in surface, corners, edges, etc

  Infills Type

• Colour Condition (compacted, dusty, etc)

• Approx. tonnage (hoover out and weigh 0.5m x 0.5m area/s)

• PSDs, use small sieves and balance
  
  Samples will be returned to the Lab for chemical analysis testing.
  
  Some rudimentary testing of the turf and components. before removal can mitigate taking unsuitable materials off-site, for example, rubber crumb which fails to meet the ECHA* standards. This can protect the contractor and client from potential liability and the plant for receiving unsuitable materials for recycling. It is also possible to use a turf monitoring tool to make sure that best practice is being followed and that the turf lifted from the site is transported to the plant. Sports Labs Trackaturf© is a unique tool that allows a client to monitor the transportation of the turf from site to plant. These testing and tracking tools provide information that will help both those at the sharp end of refurbishing old fields and those turning the old turf into new materials or products.

Photo: One of our technicians sampling rubber and sand from a field using an industrial hoover.

* ECHA’s Standards (referenced above):
ECHA’s scientific committees support restricting PAHs in granules and mulches

The Committee for Socio-economic Analysis (SEAC) has adopted its final opinion supporting the proposal for restricting eight polycyclic aromatic hydrocarbons (PAHs) found in granules and mulches used, for example, in synthetic turf pitches and playgrounds. 

SEAC adopted its final opinion on Wednesday by simple majority, supporting the proposal by the Dutch National Institute for Public Health and the Environment (RIVM) and following an earlier opinion by the Committee for Risk Assessment (RAC) in June.

The restriction proposal lowers the total concentration limit of eight PAHs to 20 mg/kg (0.002 % by weight). The concentration limits for PAHs in mixtures supplied to the general public are currently set at 100 mg/kg or 1 000 mg/kg for each of the substances. The PAHs all have been identified as causing cancer and the proposed concentration limits will be closer to the limit values for individual PAHs in articles supplied to the general public.

Currently, the levels of PAHs measured in granular infill material and mulches pose, at most, a very low level of concern (ECHA study, 2017). The aim of the proposed restriction is to ensure that the cancer risk from PAH exposure remains at a low level for those coming into contact (inhalation and skin contact) with the granules and mulches. This includes, for example, footballers, children playing on the pitches or playgrounds and workers installing and maintaining such surfaces.

SEAC concluded that the proposed restriction is the most appropriate measure to control the risks posed by these substances, and that the measures proposed would be proportionate to the risk with limited economic impacts. The proposal does not affect existing fields but will ensure that the material used for maintaining (refilling) the fields is below the new limit. The final opinion of SEAC will be published in the coming weeks.