Adani Group's leap toward decarbonising cement

Holcim India was bought over by Adani Group. Holcim is a swiss building materials manufacturer, and the company asset include  Ambuja Cement and ACC. To comply with Europe’s push to be carbon neutral and to achieve these goals within a limited time frame, Holcim Group has decided to sell its high carbon-emitting businesses to become a carbon-neutral company. This is in line with its ‘Strategy 2025- Accelerating Green Growth.’

Holcim Chief Executive Jan Jenisch,

"Around 26% of our CO2 emissions are in India, so we will have a much reduced CO2 footprint. We will always make cement, but we will decarbonise cement. We are happy to build up other segments like building solutions and products,"

In India, Holcim operated two iconic cement brands- ACC and Ambuja. Together these brands have 31 cement manufacturing facilities along with 78 ready-mix concrete plants. The deal was worth about $10.5 billion. Holcim calls itself a sustainable company that builds products and solutions out of processes that have lower emissions. It has recently invested in building facilities and technology to make green cement. However, since India is still a developing nation facility like those require high capital investment and higher standards of operations. This is currently not feasible.

Although Gautam Adani, Chairman, Adani group pointed out company's motives in pushing for clean energy and clean technology in the cement industry in India.

"With Holcim's global leadership in sustainability, we are acquiring some of the most efficient building materials operations in India, powered with clean technologies like heat recovery systems. We recognize that Ambuja and ACC operations are energy intensive and therefore when combined with our renewable power generation capabilities we gain a big head start in the decarbonization journey that is a must for Indian industry."

Cement and CO2 emissions

Cement is not a new term. It is a binder that is used in construction as it settles and toughens to resist any climate conditions. Thus, it is used for building infrastructure. The most common cement used in India is Ordinary Portland Cement (OPC). This cement is further available in different grades. These are grade 33, grade 43, and grade 53. Mostly OPC grade 43 is used in India.

Cement manufacturing is a process that produces emissions at every stage of its production. 

According to a report, 8% of the overall CO2 emissions are produced while manufacturing cement. The initial calcination reaction itself emits 4% of the global CO2 emissions. Portland Cement consists of Lime (i.e. Calcium Oxide CaO), Silica (SiO2), and Alumina (Aluminium Oxide Al2O3). When limestone is heated in a thermally insulated chamber at a temperature of about 1450deg C impurities such as Carbon Dioxide evolves. The Calcium Carbonate now turns into Calcium Oxide. This Calcium Oxide mixes with silicates and is grounded with gypsum. And, thus a powder or Ordinary Portland Cement is manufactured.

Green Cement

On the contrary, Green Cement is manufactured by an end-to-end carbon-negative process. The waste from the demolition of old buildings and the waste discarded from the industries are sourced as raw materials. The blast furnace slag and fly ash are used together in the manufacturing of Green Cement. The process is more efficient as less energy is required. The overall emissions are 40% less.

The cost of green cement is low as compared to ordinary traditional cement as the raw material used is actually the waste from the industry.   

Moreover, the purpose of cement is to provide strength. In this regard, Green cement too is the winner as it offers greater resistance. It can withstand acid rains and the process produces 80% fewer carbon emissions.

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