Greenmoves: Using waste-material bricks to reduce pollution in India

This article first appeared in City & Country, The Edge Malaysia Weekly, on December 28, 2020 - January 10, 2021.
The waste-material brick is made from recycled foundry dust and sand waste (80%) and mixed plastic waste (20%) (Photo by Rhino Machines)

The waste-material brick is made from recycled foundry dust and sand waste (80%) and mixed plastic waste (20%) (Photo by Rhino Machines)

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Outside the metropolitan areas of India, stretches of landfill are growing by the day. It is no secret that the second-most populated country in the world is plagued by waste management issues as it experiences a boom in urbanisation, industrialisation and economic development.

According to Rhino Machines Pvt Ltd, the challenges in waste recovery are aplenty in India. “We do not have a structured system for collecting and segregating plastic. Therefore, we face a shortage of plastic to recycle, but we find it on the roads, littering the cities,” says its managing director, director, CEO and promoter Manish Kothari in an email interview.

Established in 1983 as a project consultancy firm, Rhino Machines has evolved into a full-fledged manufacturing firm that produces waste-recovery and energy-saving solutions. Its innovations include RecoFlex, conventional green sand, and pouring and centrifugal casting products.

“Research or development funding is made available to start-ups, but existing small and medium enterprises find it difficult to gain access to such financing,” says Manish, an engineer with 50 years of industry experience.

“There is also a lack of [people in] education or academia who have access to finance for testing and validation. This makes our job difficult as we are unable to finance the testing and we cannot do a lot of experimentation.”

Despite this, Rhino Machines has introduced an ingenious way to manage waste and reduce pollution in India. One of its recent innovations is to metamorphose waste, specifically foundry dust, into silica plastic blocks (SPBs), or waste-material bricks. The sustainable building brick is made from recycled foundry dust and sand waste (80%) and mixed plastic waste (20%).

Manish: The thousands of tonnes of dust and plastic waste that we have today can be converted into a solution that is long term and reduces pollution (Photo by Rhino Machines)

Nearly 100% waste-material brick

In a video by Rhino Machines released in February, Manish is seen inspecting piles of foundry dust and plastic waste on a site, as he walks viewers through the entire process. “The [feedback] that we got from the industry was that they needed a solution for the dust produced when [they] reclaim sand. For every tonne of sand [they] reclaimed, it produced about 300kg of dust. The sand could be disposed of in landfills, so it wasn’t a problem. But it was very difficult to dispose of the dust,” he explains.

“About two years ago, we finalised an order with a company called Brakes India. Its executive director gave us a condition that we [Rhino Machines] would have to give them a solution for the dust and help it become a zero-discharge company.

“In the beginning, we tried different things such as making different combinations by mixing dust with fly ash, cement and gypsum, but we weren’t able to use dust in high quantities. After this experience, our team figured we would have to find a solution of our own. Our R&D team head Rajnikanth along with two young engineers, Yogesh and Nikhil, discovered that the bond between plastic and dust, and plastic and sand, is possible.”

Caption goes here (Photo by Rhino Machines)

Manish recalls the initial progress made. “We did some trials in a small machine heated with gas and found that making small blocks was possible. So, we made samples and had the blocks tested. The results showed that the bricks we had made were twice as strong as the red brick. That was when we realised we were on the right path,” he says.

“We took it a step further [in production] with a bigger machine. We realised that the cost was quite high. So, we researched more in-depth and we tried to understand the process of how the plastic injection moulding machines were being used in different industries.”

According to the firm, the process of creating the bricks involves shredding the plastic, pre-mixing the sand and plastic, heating and mixing the materials (which results in a pulp-like mixture), weighing, compressing and shaping it into forms of brick and finally, cooling the bricks before they are ready to be used.

The firm says the bricks are twice as strong as red brick (Photo by Rhino Machines)

Solution for the future

In the video, Manish recalls the challenges of creating the waste-material bricks.

“We thought about what would be the next step. We had to bring the cost closer to [that of] the red brick. We then did some research and found that we should bring down the weight in comparison to the red brick [which weighs about 2.7kg]. The waste-material brick now weighs about 2kg and is at a par with the cost of a red brick.

“What’s next? We have created a solution for this, and find that the waste-material bricks can be used in construction and can be turned into different shapes. In the future, this project will need three things. First, we will need architects or civil engineering bodies who are in the field to research this product on its possible uses and to validate it. Second, civil society, municipal corporations and industry need to join hands and set up this project as a community service responsibility activity so that all the waste that is surrounding us can be converted into something useful.

“And third, to scale up the project, the industry should research how we can further reduce the energy and production cost. The cost of bricks made from clay and water is very low, which makes the marketing of the project for bricks and paver blocks not viable. We have, therefore, shifted our product mix and are now rebuilding the business model for it to be self-sustainable.

“We would like for the institutional bodies and the industry to work together. From what I understand, the thousands of tonnes of dust and plastic waste that we have today can be converted into a solution that is long term and reduces pollution.”

Manish highlights Rhino Machines’ future plans for the waste-material bricks. “We have signed MoUs with academia, and with persistent interaction, we have pitched in innovation programmes to gain access to funds and validation of the technology. We have also tied up with non-profit social organisations for awareness and to build jointly replicable models that can be taken to remote areas in India, and also offer the entire solution globally. [We plan] to build an e-commerce platform for the sale of end-products such as benches, stools, tables and decorative stuff,” he says.