From Waste to Fuel | Sustainable Development | CEMEX
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Sustainable Development

From Waste to Fuel

As part of our sustainability efforts, we continuously strive to find ways to meet the demands of a growing urban society without compromising the planet for future generations.

We’re creating new purposes for materials that traditionally would have entered the landfill, providing our communities with an effective and secure way to alleviate the social, economic and environmental issues associated with municipal waste management. For example, our alternative fuels program is a key part of our sustainable manufacturing.

Through co-processing – the utilization of waste as a source of energy – and the use of ashes from combustion, we’re reducing the use of extracted raw materials.

For more information on CEMEX's position regarding Alternative Fuels please click here

Over the past decade, our alternative fuels substitution rate has risen almost six-fold, from 5.1% in 2005 to 23.3 percent in 2016. At year-end, 92% of our cement plants burned alternative fuels, avoiding the use of 1.6 million tons of coal.

CEMEX has become the leading user of alternative fuels in the cement industry, replacing traditional fuels like petcoke and coal with those that have a lower carbon emission factor as well as carbon neutral alternatives, such as biomass residues.


Advancing our Waste Reduction Management

At CEMEX, we dispose of the waste generated by our production processes in accordance to local regulations. In terms of operational waste streams, cementkiln dust represents the largest amount of waste we produce. We try to reuse it in production and other processes as much as possible and seek to monitor, minimize, reuse and recycle all of our wastes when possible.

To minimize the amount of generated waste sent for disposal, we have integrated waste management into our operations in several respects. We reuse many of the by-products of our operations—for example, cement kiln dust (CKD)—in our production process. We commonly add CKD to finished products and use it to stabilize waste or for environmental remediation. We seek additional beneficial uses for any CKD produced and, through good operational practices, keep to a minimum the proportion that we send to landfills. The rest of our operations produce comparatively little waste.

Other efforts include:

  • Monitoring of hazardous and nonhazardous waste generation in all of our operations
  • Replacing primary aggregates with other discarded materials (e.g. demolished concrete)
  • Reusing and recycling fresh concrete returned from construction sites

For more information on CEMEX's position regarding Aggregates Recycling please click here

Thanks to these efforts, 94% of our waste has been recovered, reused and recycled, meaning only 6% of the waste generated by our operations is sent to disposal sites.

In addition to minimizing the waste produced by our operations, we are increasingly using society's waste—chipped tires, sewage sludge, household waste, and biomass such as rice and coffee husks, sawdust, and palm residues—as alternative fuels in our cement kilns. In the process, we are diverting societal waste from landfills and using it to displace fossil fuels and reduce CO2 emissions. We are also using by-products from the steel and power industries, such as fly ash and blast furnace slag, as alternative cementitious materials to reduce the percentage of clinker in our production process and help reduce energy consumption.