Nature is unable to decompose plastic such as polyethylene, which is often used in shopping bags and single-use plastics (water bottles, the lids of disposable coffee cups, straws, coffee stirrers etc), and dumping it in landfills exacerbates environmental and economic problems.
As surprising as building with plastic sounds, it could be one answer to our planet’s plastic crisis.
The Eco-Block is an environmentally-friendly brick made from recycled materials and construction waste. It was invented at the Hong Kong Polytechnic University in 2006.
Eco-Blocks are made of plastic, rubber, and electronic waste products that have been melted into casts resembling building blocks for sustainable construction projects.
The Center for Regenerative Design and Collaboration (CRDC) in Costa Rica can turn any plastic, be it dirty or clean, into sustainable building blocks that can guarantee structures with an infinite lifespan. For this, they use the REAP process (recover, enrich, appreciate, and prosper) by recovering “tragic plastic” (unrecycled plastics from rivers, beaches, roadsides etc) and turning it into “eco bricks”.
CAPE TOWN, SOUTH AFRICA – NOVEMBER 8: A block of ‘eco bricks on display, plastic bottles tightly packed with litter to form a substitute build block on November 8, 2015 in Cape Town, South Africa. A worldwide movement, ‘Open Streets’ hosted the Social Innovation Festival in Langa. As part of Open Streets Day a portion of streets are closed off to all motorized traffic to allow free access for community and visitor social access as well as various other activities, including a showcase of entrepreneurial projects. (Photo by Gallo Images / Dino Lloyd)
“In REAP ‘r’ is getting the plastic, ‘e’ is enriching it with PRA [pre-conditioned resin aggregate], ‘appreciate’ is when we mix it into the concrete, and ‘prosper’ is because we are adding value,” says Deon Robbertze, global communications director at CRDC.
After the plastic has been collected, it is shredded and enriched with two inert compounds that give it strength and stability; it then goes into an extruder, and comes out, looking like a glazed sausage, before being crushed into aggregates of 6.5ml.
The aggregates referred to as Ecos PRA are used as substitutes for stone aggregates such as natural sand and gravel that are used in the conventional process of producing cement, making Eco-Blocks lighter and stronger, while adding value to the structure.
Eco-Blocks are a product of the PRA and cement mixture. The entire manufacturing process is solar-powered, and emissions are few, making it environmentally friendlier than most other methods.
Robbertze says tragic plastics make up 1.1 tons of plastic going into landfills in South Africa.
“There has been a massive backlash globally over the last three to four years against plastics, but the thing is, we’re not going to get rid of it. [We use] so much [plastic], from our packaging to vehicle parts. Recycling has worked [for a while], but it’s failed because there’s just too much of it.”
“Coca-Cola and Pepsi in the US left the US plastic body about two weeks ago, so the producers are sitting with the problem because there is backlash from environmental groups and the public. We are producing 396 million tons [of plastic] a year globally; if you look at Coke and PET bottles, it’s a million a minute and only 25% of those are being recycled.”
In South Africa, 1.5 tons of plastic are consumed annually. According to the 2016 annual Plastics SA report, South Africa recycles 21% of plastics consumed, with the remainder ending up as pollution or disposed of in landfills.
Cleaning up litter and illegal dumping comes at a significant cost for municipalities, using money that could have been allocated to other priorities, such as the provision of housing, electricity, water and sanitation.
Eco-Blocks are also an opportunity to create jobs for low-income individuals. In South Africa, CRDC plans to distribute mobile shredders in low-income communities where people will collect and dump their plastic waste for processing in CRDC’s smaller factories that can process 2-5 tons of plastic a day.
In developing countries, low-income communities who cannot afford housing are able to harness the PRA and convert it into sustainable building material. Building with Eco-Blocks helps reduce CO2 emissions, water, and energy consumption. It also contains additives that make the material fire and earthquake resistant.
Robbertze says one of the things that help lifts people out of poverty is to have a house that increases in value because it is well-built and easy to resell. CRDC has started building houses in Costa Rica with the help of its partner, the NGO Habitat for Humanity.
“The key thing in South Africa is that we want to put a call out to communities to bring us their plastics; we’ll make it into a PRA and into concrete blocks with partner organisations, and then build houses that increase in value because they are built with a better, stronger brick.”
Communities will also earn an income from plastic organisations.
Other types of Eco-Blocks, known as EcoBricks, are made by stuffing plastic waste into water bottles. You may not be able to build an entire house with an EcoBrick but you can get creative.
According to a report published by Plastics SA in 2018, “South Africa has a dynamic, growing and well-supported plastics recycling industry.
“Despite facing major challenges last year, the plastics industry made important strides forward. Plastic bags manufacturers removed fillers to produce bags that are fully recyclable. In addition, 100% certified recycled plastic material is now used to produce some carrier bags.”
Anton Hanekom, executive director at Plastics SA, adds, “This creates an end market for recycled plastic products and helps to reduce waste to landfill. By ensuring that the products we create become part of a circular economy, we create a win-win situation for the environment and for the industry, that employs 60,000 people”.
Plastics SA looks to improve South Africa’s waste infrastructure, reduce contaminants in the waste stream, aid recyclers, and develop alternatives for difficult to recycle plastics. But in the meantime, plastics still cram our landfills. ML