Is recycling down in the dumps?
Construction debris is looking increasingly attractive to material recycling initiatives in Qatar
Reusing construction debris is the focus of Qatar’s Minister of Environment, HE Ahmed Amer Mohamed Al Humaidi, who issued Qatar Construction Specifications (QCS) in 2014 with one of its core objectives being to reuse the ever mounting construction debris.
According to the Ministry of Development Planning and Statistics, more than 77% of the 12,163 MTs of the solid waste generated in Qatar in 2013 was from the construction sector, which not only poses health hazards but also occupies huge areas of space.
Salim Kutty, company manager, Lafarge Aggregates in Qatar underscores the need for recycled material: “Local product demand comes to about 40-million tonnes per year, for the next four years, but the market capacity is from 15 to 20 million tonnes, resulting in a huge gap between local and imported products which, when added together, you are looking at about 35-million tonnes deficit per year.”
Consequently, Lafarge recently launched a recycling plant at the landfill Rawdat Rashid near Salwa road.
Professor and chair of the Department of Civil Engineering in Qatar University, Dr Ramzi Abd Taha, says that Qatar has a severe aggregate shortage and most of it is imported from the neighbouring UAE.
This is exacerbated by limited port facilities in Mesaieed in terms of receiving and stockpiling aggregate needed for building and road construction projects.
Therefore the advantage of using alternative materials such as construction and demolition debris will generate economic benefits, speed up construction and conserve good limestone aggregate sources in Qatar for future generations, he points out.
In an original initiative, a project entitled ‘Innovative use of recycled aggregate in construction’ was taken up by the UK Transport Research Laboratory (TRL) together with Qatar Standards in the Ministry of Environment, Qatar University, and the Public Works Authority, Ashghal.Funded by Qatar National Research Foundation (QNRF), the TRL's role was to bring the government and industry to work in partnership for the use of recycled aggregates as well as develop national recycling specifications.
As part of the project, Boom Construction laid a one km-long stretch of road costing around QAR1.2m and made use of 210,000 tonnes of reclaimed rubble in October 2014.
The success of the project instilled confidence among the authorities in the use of recycled aggregate locally, and QNRF awarded another project to TRL for the implementation of recycled materials in various construction applications.
Dr Khaled Hassan, Regional Manager of TRL and lead principal investigator of the project, says, “The greatest benefit of recycling is protecting the environment by reducing the amount of construction waste accumulating in landfill sites as well as reducing reliance on imported aggregate, and therefore the high carbon emission associated with extracting and transporting virgin aggregate from neighbouring countries.”
Matteo Gioia, regional marketing communications manager, Construction Chemicals Division ORA: Middle East, West Asia, CIS & Africa, says, “The construction, rehabilitation and maintenance of bridges and roads are integral to the overall infrastructure quality and development in urban environments.
“In the Middle East, we see governments increasingly demanding rapid construction and an extended service life of structures. This poses a challenge to designers and engineers in light of intensive traffic loads, as well as extreme weather conditions and environmental impact from chlorides and sulphates.”
The benefits of using recycled aggregate are vast, including low carbon dioxide emissions, reduced transport distances, preventing adverse impacts on the environment owing to dumping of material, and also saving money as importing aggregate is costly.
The cost of recycled materials is always less than the conventional, particularly in low-lying countries such as Qatar, Kuwait and Bahrain with a shortage of local aggregate, Hassan says: “The saving is related to the allocation of recycled aggregate whether it's replacing imported or local aggregate.
“However, the greatest benefit will be in protecting the environment,” he stresses.
While most of the aggregate used in Qatar is imported from outside and there are significant benefits around recycling, consistency in quality is a concern, as Taha points out: “The long-term field performance of such materials has to be monitored under actual environmental conditions such as temperature, rain, traffic, etc.
This takes time, but laboratory results are encouraging. It is important to do research to establish the final acceptability of using such materials in road construction and elsewhere,” he says.
In addition, by recycling construction waste within Qatar, the given target for recycled aggregates as part of the Qatar National Development Strategy will be met.