Turning PPE waste into bricks sans cement a reality

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A team of engineering students has devised a method to turn hospital Personal Protective Equipment (PPE) waste, which typically swells-up landfills, into bricks that are stronger and do not use any cement. Not only do these poly bricks have a 3-time higher compressive strength as compared to the common red bricks, they are much lighter and can be produced in a far shorter time.

Since the curing time to reach ISO standards is less than 24 hours, the bricks are ready quicker and cheaper than common red or concrete hollow bricks and meet the water absorption specifications.

By showcasing a working model for creating poly bricks the team of civil engineering students from Sona College of Technology, Salem emerged winners from among 25 teams that participated in the All India Council for Technical Education (AICTE) Smart India Hackathon held at Jaipur bagging a Rs 100,000 prize.

The poly brick making process starts by sterilizing PPE kits with ultraviolet (UV) rays, subjecting it to heat at 160 degrees centigrade, adding sand aggregates and casting the polypropylene mass into bricks. Dr N Karuppasamy, Assistant Professor of Civil Engineering, Sona College of Technology who mentored the team said that a patent application has been filed for this technology.

Poly bricks sans cement and water

The poly bricks are eco-friendly as they do not use any cement or water in the process and cause minimal in process emissions as the PPE plastic waste is subjected to less than 200 degrees centigrade. The added edge of poly brick production is the total elimination of cement typically used in manufacture of hollow concrete bricks. No cement use eliminates carbon emissions generated during cement production.

The WHO, in a February 2022 report, brought out the added burden that the use of PPE kits used during the Covid-19 pandemic was putting on the environment, due to their single-use nature. The medical waste, including PPE kits, surgical masks among others, made of polypropylene plastic puts a tremendous strain on waste management systems.

When the 5-member civil engineering student team from Salem based Sona College set out to look for the most innovative method to manage several thousand tonnes of waste generated by discarded PPE kits in hospitals their lead mentor Dr R Malathy, Dean (R&D) and Professor of Civil Engineering added an additional dimension of “creating wealth from this hazardous waste”.

The team from Civil Engineering department of Sona College — Aravind Kumar from final year, Kamalesh J B and Dharani Raj U, both from third year, and Adhavan P and Harshini E K, both from second year — found this solution while participating in a nation-wide competition to find ‘an effective method for tackling improper disposal of COVID personal protection equipment which leads to an additional strain on the city authorities grappling with single-use plastic menace’.

Ready for Technology Transfer

Mr Chocko Valliappa, Vice Chairman, Sona Group of education institutions, said, “Working in a group the students came up with a solution through innovative and quick thinking. The technology is now available to hospital chains and other organizations interested in technology transfer to help tackle PPE waste and also reduce poisonous emissions.”

The technology owes its genesis to the Covid-19 pandemic, keeping in mind the additional PPE waste generated – which was almost 56,000 tonnes in one year, as per data by Ministry of Environment, Forest and Climate Change, Government of India. This is in addition to the PPE waste hospitals and healthcare providers generate as part of their regular operations.

These eco-friendly bricks can be used as regular bricks for walls as also as paver blocks instead of red bricks – in the process reducing plastic waste as well as pollution caused during cement production. The poly bricks have good cement adhesion and can be plastered with cement.

While cement use is ubiquitous in construction, manufacture of poly bricks and paver blocks from PPE waste with absolutely zero water or cement promotes a reduction in water wastage, harmful emissions, as well as contamination of water by microplastics.

The Civil Engineering Department has also patented a technology to use plastic waste in brick production that replaces almost 70% of sand with plastic.