Blended cements are slowly but steadily increasing their presence felt in the market. With the introduction of composite cement, the industry’s green commitment is getting reinforced further.

Blended cements – Portland Slag Cement (PSC) and Portland Pozzolana Cement (PPC) – are making headway by cornering a major share of the cement market, nudging the Ordinary Portland Cement (OPC) which was the market leader at one time, into the corner, in the recent years. The exciting journey of blended cements has seen them taking an equal share of 50:50 in the late 1970s even before introduction of fly ash-based blended cement, only to lose share to OPC which touched 76 per cent by 1983, and to totter at about 30 per cent by the end of the twentieth century, it has now scaled the peak market share of three-fourths.

"Ever since government allowed blending of cement with OPC, there has been continuous growth in the sales of PSC/ PPC cement. There has been a very good penetration of blended cements in the market. Earlier OPC used to be the market leader in India. However, today, it represents only about 20-25 per cent of the market share. In this context, it is encouraging to note that nearly 75 per cent of cement production in India at present is in the form of blended cement of various types," says Raakesh Jain, Chief Sales Officer, Nuvoco Vistas Corp.

Blended cements have been gaining almost over the last couple of decades, particularly since introduction of fly ash-based cement, which combines the advantages of OPC on cost front, and strength and durability of slag cement, its blended peer. "This has been possible through education of customers on the merits of blended cement, which has led to higher awareness and increased usage," says Ujjwal Batria, Chief Operating Officer, Dalmia Cement (Bharat) Limited.

With the introduction of composite cements, the market is expected to become even more exciting in the years to come.

Institutions still prefer OPC
Still, OPC is preferred in certain geographies and particularly by several institutional users, for various reasons. "While there is an improvement in the acceptance of blended cements, there are certain segments like RMCs, select infrastructure projects, where the preference continues to be for OPC due to the cost economics and flexibility available to the contractor," says Nilesh Narwekar, CEO, JSW Cement.

OPC grades 43 & 53 are more preferred in major infrastructure projects such as national highways, bridges, transmission lines, power plants, industrial and residential structures. "Also in major infrastructure projects, OPC Grade 43/ 53 is approved through the Central/ state government/ local governing bodies/ institutions over PPC/ PSC, making OPC a preferred product in institutional segment," says Jain.

Institutional customers have their own batching plants in most cases and prefer to do blending at their end. However, efforts of the blended cement manufacturers over the last few years in educating their customers on environmental benefits and durability they offer have resulted in their increased use.

Applications
Both PPC and PSC are environment-friendly cements as they use industrial by-products as an input. PPC classically uses fly ash, while PSC uses slag generated in the blast furnace of steel plants.

Blended cements are suitable for high rainfall areas and coastal areas as these offer higher longevity of structures, offering the highest resistance against sulphate and chloride attacks and environmental pollutants. PSC’s chemical composition gives it high compressive strength and offers excellent resistance to chloride and sulphate attacks. It boasts a superior finish and minimise shrinkage and cracks. For this reason, it is mostly used for marine constructions.

PPC’s hydration process is slower than PSC cement, therefore, making it suitable for mass concreting. It shows greater resistance to aggressive weather and is cheaper than PSC. PPC has an amazing pore refinement leading to an improved density of concrete, says Batria.

New kid on the block
Taking cue from the Bureau of Indian Standards’ (BIS) decision to permit manufacturing and selling of composite cement in India a couple of years ago, several cement manufacturers have already introduced composite cement. Composite cement is a blend of fly ash and slag based cement, offering the best of both worlds.

Composite Cement is being typically manufactured by companies where both these commodities are readily available. Eastern region is where most of the players have introduced composite cement by now. JSW has introduced it in Karnataka and in the east, while Dalmia Cement has introduced it in the eastern region, and Nuvoco already has a thrust towards blended cements.

"We have already introduced composite cement to our customers in Karnataka and more recently in Salboni. We also plan to make it the core product from Jhajpur, our upcoming plant in Odisha," Narwekar says.

Being a new product in the market, the manufacturers are already undertaking awareness programmes for their customers and influencers like engineers and architects. Composite cement is still not accepted in RCC (Reinforced Cement Concrete) by BIS posing a challenge in selling it as an all-purpose cement, besides getting government approvals for composite products.

Looking ahead
If one has to go by what the experts have to say, bended cements are going to be the future of cement industry, being greener and offering several advantages. Perhaps in the process of vouching for its future of cement in blended ones, JSW Cement, being largest manufacturer of PSC, is planning to take a plunge into blended cements headlong.

"We are planning to double our cement production capacity in the next few years to meet the growing demand for "Green" cement in the eastern region by a combination of brownfield expansions at our new facility at Salboni, West Bengal and Shiva Cement, Odisha. These projects are expected to be commissioned in various phases until 2023. We are also debottlenecking our plants in South and evaluating opportunities for a grinding unit GU in TN," Narwekar says. JSW is in the process of commissioning a new greenfield 1.2 million tonnes per annum plant in Jajpur, Odisha, which is expected to be optimizes by December 2019.

In order to promote sustainable alternatives in every area in line with India’s commitment at the Paris Summit, blended cements, which use factory waste and other by-products, should be encouraged through use in government projects. Thus, cement manufacturers, who are planning to increase their use of alternative fuels and raw materials (AFR), will be contributing immensely to sustainable manufacturing and sustainable products in future.

– BS SRINIVASALU REDDY