Co-processing, a practice in which Votorantim Cimentos is a pioneer in Brazil, is a prime example. The technique consists of using waste or byproducts of other industries and tyres as sources of energy to replace the traditional fossil fuels and non-renewable raw materials used in cement production. Important for sustainability in the cement industry, co-processing also reduces energy costs and the emission of gases that cause the greenhouse effect, being the best alternative for waste disposal, due to complete elimination and removing the need to generate new landfill.
Annually, about 800 t of industrial waste is processed at the company’s plants in Brazil, including waste from steel, petrochemical, automotive, aluminum, paint, packaging, paper and used tyres. The Rio Branco do Sul (PR) plant has eliminated about 26 million scrap tyres during the 24 years it has been employing this technique. In 2013, the unit reached a record consumption of tyres, avoiding 7000 t of CO2 emissions and eliminating 54 000 t of tyres.
Alternative raw materials
However, the diversification in the use of materials in the production process has gone beyond the co-processing path, as seen in the Porto Velho (RO) unit. The unit, located in the north of the country, is the first to produce 100% pozzolan cement. The plant in the Amazon was built in a record time of 18 months, with investments of R$176 million and production capacity of 700 000 tpy of type IV cement (according to Brazilian and European standards), with the addition of 34% pozzolan.
The production of a different kind of cement in northern Brazil enabled very significant reductions in greenhouse gas emissions and waste, in the use of water and energy and in the cost of production. Compared with a conventional cement plant, the Porto Velho unit emits 43% less CO2, generates 10% less waste, and consumes 25% less electricity, 10% less thermal energy and 40% less water.
This is part two of a three-part article written for World Cement’s December issue and abridged for the website. Subscribers can read the full issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the December 2015 issue here.
Read the article online at: https://www.worldcement.com/the-americas/30112015/advances-reduction-co2-emissions-part-two/