By Christine Marlet, secretary general,
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
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.
| Brieselang gypsum plant
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
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
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 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
Country Mixed aggregates Concrete aggregates
<0.5 or <1% % SO3
<1% SO3 content
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
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
Construction waste: waste resulting from construction
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
- 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
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
The current targets are:
- UK Economy zero plasterboard waste sent to landfill by
- UK plasterboard manufacturing operators zero plasterboard
waste to landfill by 2015
- UK Economy increase recycling of new construction
plasterboard waste to 50% by 2015
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
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
Selective deconstruction enables an increase in;
The materials quality
Potential for future use
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
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
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
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
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
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
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
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
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