Open/Close Mobile Menu Open/Close Mobile Menu

GtoG: A Life+ project where the UK plasterboard manufacturers are involved

By
Published: Thursday, 17 April 2014

By taking part in the Gypsum to Gypsum recycling project, major plasterboard companies British Gypsum, Knauf and Siniat will have access to modern technological developments for gypsum recycling and plasterboard waste management in the European gypsum industry to improve management and processing of gypsum waste.

By Christine Marlet, secretary general, Eurogypsum

In January 2013 Siniat Ltd joined a European collaborative project aimed at increasing recycling of construction and demolition plasterboard waste.


The project was named from Gypsum to Gypsum (GtoG) in order to reflect the link between the recycling industry, the demolition sector and the gypsum industry. The principle was to transform the gypsum demolition waste market through recycling and the project is expected to run for three years, finishing December 2015.

 
 Brieselang gypsum plant
Source: Eurogysum
The market transformation began with the establishment of a collaborative business model between the demolition/processing/manufacturing and recycling industries. The project is co-financed by the Life+ programme and coordinated by Eurogypsum.

Eurogypsum is made up of the European Association of plaster and plasterboard manufacturers GtoG and involves 17 European partners from the UK, Belgium, Germany, France, Denmark, Greece and Spain.

Surveys on waste recycling, deconstruction practices and economics were carried out in 2013 in the major European gypsum product consumers, namely in France, Germany, Belgium, The Netherlands, Spain, Greece and Poland. This was necessary due to the strong regional orientation of current practices.

Pilot projects implementing the deconstruction techniques, the decontamination, the waste qualification and reprocessing in Gypsum manufacturing plants will be carried out in France, the UK, Germany and Belgium during 2014-2015. The outcomes of these pilot projects will be used to reassess the findings of the surveys carried out in 2013.

The project work to be performed includes in summary:

• Diagnosis of buildings prior to deconstruction;
• Auditing and the creation of an inventory of recyclable materials;
• Decontamination of waste if necessary and separation of different waste streams (sorting and segregation);
• Processing of the gypsum waste received;
• Qualifying gypsum waste and, finally;
• Reprocessing of the waste in plasterboard manufacturing plants (cradle to cradle approach).
• Establishing the end-of-waste criteria for the recycled gypsum powder

Close-loop recycling

Gypsum products can be counted among the very few “green” construction materials where “closed-loop” recycling is possible (where the processed waste (recycled Gypsum) is used as secondary raw material to make the same product again). Gypsum as such is 100% and eternally recyclable. You can always reuse gypsum because the chemical composition of the raw material in plasterboards and blocks always remains the same.

Gypsum waste in landfills (if disposed of with biodegradable wastes) might generate environmental problems such as sulphur leaching, contamination of the ground water and creation of odorous and toxic hydrogen sulphite gas.

Gypsum is found in large quantities in recycled aggregates coming from construction and demolition waste (C&DW) without selection at source. This material is considered as an impurity in recycled aggregates due to the negative effect on concrete and mortar properties. In this sense, the gypsum content is a good indicator in order to evaluate the quality of mixed recycled aggregates for its application in the production of concrete and mortars. Sulphates content present in gypsum must be controlled, because they can lead to expansions in concrete. According to standardisation, soluble sulphate content of recycled aggregates is limited and gypsum content is directly related to this property.

Most countries have gypsum content limits for the use of C&DW derived secondary aggregates.
 
Permitted Gypsum content in C&DW derived secondary aggregates

Country Mixed aggregates Concrete aggregates

Country

Mixed aggregates

Concrete aggregates

Germany

<0.5 or <1% % SO3 content

<1% SO3 content

France

<1%

Virtually 0%

UK

n/a

<1%

Belgium

<1%

<1%

The Netherlands

<1%

<1%

Italy

<1%

<1%


Gypsum waste that has been properly sorted out can be recycled in gypsum plants to produce plaster and plasterboards.

The Landfill Directive sets out the general conditions for the landfilling of waste with the aim of minimising the impact of landfill on the environment and to encourage waste minimisation and recycling. Regulations set out the criteria for the acceptance of gypsum and other high sulphate bearing wastes at landfill.

Recycling plasterboard waste

The European Gyspum Industry has three categories of gypsum waste based on origin:

• Production waste (e.g. gypsum products which do not meet specifications and waste resulting from the manufacturing process).
• Construction waste: waste resulting from construction sites.
• Demolition waste. The last category includes both demolition and refurbishment waste and is the most complex to address because the waste stream includes other construction materials (such as plasters, paints & screeds etc).

The European Gypsum Industry recycles with ease:

  • Production waste is generally recycled by the factories and used as a raw material.
  • Construction waste collection and recycling is increasing in Scandinavia, France, the UK and Benelux.

However the re-incorporation rate of the recycled gypsum in the manufacturing process differs from country to country and from plant to plant.

The European Gypsum Industry recycle far less demolition waste for the following reasons:

  • The buildings are currently crushed and not dismantled, thereby impeding the sorting of plasterboard before the building is demolished;
  • Plasterboard is a relatively new product used in construction after the second world war and we are now only beginning to dismantle buildings with plasterboard linings;
  • Gypsum demolition waste tends to be contaminated (screws, vinyl wall paper etc.) this renders the treatment more complex at higher costs and limits the ability to use the resulting material.

Statistical data

There are very limited statistical data available on plasterboard waste generation beyond anecdotal evidence and ad hoc projects. Figures from different sectors of the industry (recyclers as well as manufacturers) are being quoted with limited evidence base.

Business model to recycle plasterboard waste

The business model differs from country to country according to the culture and environmental legislative framework of that country. However there are main characteristics which are valid for any kind of C&DW recycling.

The C&D recycling systems always involve more than one operator. Each operator has its own responsibility in the economic, technical and environmental efficiency of the recycling of the C&D waste stream:

Waste collectors can also be recyclers and recyclers can also organize the waste collection. Manufacturers can also be recyclers (having internal recycling facilities) and they can also collect waste. Some gypsum manufacturers have put in place take back schemes for collecting construction waste.

The efficiency of the recycling lies in the efficiency of the value chain.

The efficiency of the value chain also depends on the monetary value of the recycled C&D gypsum waste: metal has infinite value and is thus recycled. Plasterboard is a commodity and has little monetary value for the waste collectors, the demolishers or the contractor.

The sorting at demolition and construction sites will happen for plasterboard if

  • National authorities push for dismantling, recycling or recovering of the plasterboard waste;
  • Other types of waste of high monetary value are recovered at the same time;
  • Logistics are optimised.

Otherwise, the landfill route will still be seen as the easiest and often most economically viable route.

The UK example of recycling Gypsum based waste

The Ashdown Agreement on plasterboard recycling between the Gypsum Products Development Association (GPDA) and Waste & Resources Action Programme (WRAP) took effect from 1 April 2007. It sets out shared objectives for the diversion of waste plasterboard from landfill. The progress achieved regarding the agreed targets are reviewed and updated annually.

The current targets are:

- UK Economy zero plasterboard waste sent to landfill by 2025
- UK plasterboard manufacturing operators zero plasterboard waste to landfill by 2015
- UK Economy increase recycling of new construction plasterboard waste to 50% by 2015

RESULTS 2012

• Target 2 Zero production waste to landfill; 
•The 2012 generic (cross industry) data was zero tonnes, so that the GPDA continue to achieve the 2015 target
• Target 3 Target 50% of construction waste recycled by 2015 to environmentally acceptable uses (plasterboard, cement or for agricultural use) based on annual production of 210,000 tonnes
•The quantity recycled by manufacturers-close loop recycling reached 68,988 tonnes or 32.9% in 2012 (62,750 tonnes or 29.9% in 2011) so a 3% improvement on 2011. The next challenge to address is how to measure the contribution of cement and agricultural use, which is being developed through the Plasterboard Sustainability Partnership (PSP) .

Dismantling and sorting on site: the practice to promote

Selective deconstruction enables an increase in;
• The materials quality
• Potential for future use
• Economic value.

However, the current average demolition techniques employed throughout Europe are reducing raw materials quality, potential for future use, and economic value into, i.e., aggregates for road, filling material and in some cases, preventing close-loop recycling (gypsum products) as the building is just crushed.

Deconstruction should also be applied in major renovation and light renovation of buildings. Internal partitions within an office can be dismantled where an office is being refurbished. This is not the current practice. Education of the workforce is essential to create a dismantling mentality when it is easily implemented.

Applying dismantling techniques instead of using traditional demolition techniques will lead to sorting and recycling of non-load bearing elements for reuse in the production process. However, as the waste characterisation differs, the production processes of the manufacturers must be adapted to increase the recycled content in the product.

Notwithstanding the above, some good practices do exist. As an example –

In the UK, with the inception of the Site Waste Management Plan Regulations (SWMP) in 2008, the demolition industry tends to have a good idea of the amount of Plasterboard to be removed from a building. The demolition industry is also able to stream all other materials fairly accurately as well. Although the SWMP Regulations do have a minimum threshold (£300,000) for when the Plan is required, with the type of software formats available for the plan and the reasonable ease with which they can be populated, this can be done reasonably easily and without too much resource required.

On the other side, in France, a study on 15 selective demolition sites showed that at least 50% of Gypsum based waste did not comply with the quality required due to a bad dismantling process.
The dismantling process includes separate sorting of the waste on site (same requirement as for construction waste) and an efficient collection system.

Dismantling a building should therefore become standard if we are serious about implementing a cradle to cradle approach in recycling.

Current recycling in Europe

Recycling of Gypsum construction and demolition waste is mature in some countries such as the UK, France, Benelux and Scandinavia. There is still a long way to go before we achieve the 70% recovery target of the Waste Framework Directive for the other countries

The “closed-loop recycling concept” contributes to fulfilling the environmental objectives of the Waste Framework Directive.

But this recycled gypsum must fulfil the quality requirements of the European gypsum industry. In this case the recycled gypsum can be used as raw material next to natural gypsum and synthetic gypsum for production of new gypsum based construction materials.

To achieve the closed-loop recycling concept the following considerations will need to be met;

• Deconstruction (dismantling and sorting/separating on site) is crucial for recycling and should become the focus of European regulatory and non-regulatory measures in the future;

• We should create an increased demand for the use of recycled gypsum with non-regulatory incentives stemming from the national government (example of the UK).

• On the basis of the Waste Framework Directive and the upcoming results of the GtoG project terms like recyclable waste, recyclability, recycled waste, recovery, backfilling, recovery and recycling targets etc. can be clearly defined between all stakeholders involved in the management of plasterboard waste streams in a common understanding.

With this approach, recycling primary raw material resources can be saved, recycling rates and resource efficiency can be increased and recyclable waste streams to be landfilled can be reduced.



 



More like this