Co-process to use plastic waste better

Plastic is everywhere -- from the oceans of the world to landfills located on the peripheries of cities to the morning walk trail that one might take. It is hurtling us towards a disastrous tomorrow.

To put the problem in perspective, let’s look at some of the shocking statistics: The Central Pollution Control Board (CPCB), pegged plastic waste generation in India at 9,500 tonnes per day (TPD) in 2019 growing at a Compounded Annual Growth Rate (CAGR) of 15%, i.e., doubling every 5 years. This means by next year India will generate almost 19,000 tonnes of plastic every day.

Refill-reuse and recycling are the most effective ways to minimise plastic waste generation. However, when plastics reach their end-of-life (EoL)--when they can neither be reused or recycled--there are better ways to deal with the plastic waste than sending it to a landfill. One way is to use plastic in cement manufacturing – this is known as co-processing.

Cement manufacturing involves intense heat (around 1,500 degrees Celsius), which is traditionally generated by burning coal and petcoke. Co-processing involves substituting a portion of the fossil fuel feed with other fuels, in this case, plastic waste. In other words, the material and energy value present in plastic wastes can be fully utilised in the cement kiln as a replacement for the fossil fuels that are commonly used. The CPCB terms co-processing as a more environmentally friendly and sustainable method of waste disposal as compared to land filling and incineration, since production of harmful dioxins and furan emissions are avoided
and residues, if any, are effectively managed.

Today, energy costs often contribute to almost a quarter of cement companies’ bottomline. With increasing demand for energy in India, the availability, cost and supply of coal and petcoke are expected to become increasingly erratic with periodic price shocks. Since the availability of plastics in municipal waste is not expected to vary as uncontrollably, cement companies can hope to achieve better fuel price stability with this fuel.

Co-processing of plastic waste in cement kilns is very realistic owing to the availability of plastic waste. As per statistics from the Ministry of Coal, the cement sector used a total of 25.8 million tonnes (MT) of coal in 2022, of which 7.57 MT was domestic and 18.23 MT was imported. There is more than enough plastic waste lying around to meet the bulk of this energy demand.

Traditionally, getting this plastic waste to cement manufacturers would require the latter to engage with bulk plastic waste generators and aggregators, develop dependable supply chains, install plastic waste pre-processors to make plastic waste ready for co-processing, etc. This arduous process can be converted into a business opportunity by leveraging the Extended Producer Responsibility (EPR) mechanism under the Plastic Waste Management Rules (2016).

EPR is a policy mechanism under which Producers, Importers and Brand Owners (PIBOs), involved in the production and use of plastic packaging, are responsible for reuse of plastic packaging, recycling of plastic packaging waste, and EoL treatment of plastic.

Since PIBOs often lack EoL waste management capabilities, they may enter into business agreements with cement manufacturers to delegate their EoL responsibilities against a monetary consideration. This transaction would be documented in the form of an EPR certificate. On account of the co-processing potential, cement kilns have been identified as a principal recourse for EoL treatment, and cement manufacturers as important plastic waste processors. Over 70 cement units have already registered as Plastic Waste Processors by mid-March of 2023. By financial year 2025, almost 6,000 TPD worth of EoL certificates are expected to be traded and these volumes are expected to grow at a CAGR of 8.80% thereafter.

In addition to registration, however, cement manufacturers must act quickly on several other fronts: enter into long-term agreements with bulk generators and aggregators to ensure continuous supplies of plastic waste; set up a mechanism to sign forward sale contracts of EoL certificates so that both rates and supplies are guaranteed; invest in a supply chain that optimises supplies, reduces order times, and diversifies sources of plastic waste.

(The writer is the director- Water, Sanitation & Hygiene (WASH) at RTI International India)