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Low magnesia cement

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Impurities in cement are not completely avoidable; while some of them can be ignored, compounds like magnesium oxide are extremely dangerous for the integrity of the structure. Cement companies try to have minimum possible magnesium content in the product, to improve the strength and durability of the building.

Dalmia Bharat Cement is one of the leading cement manufacturers in India and has mastered the art of producing low magnesia cement products. CV Suvasan, Sr. General Manager from the Tech. Services & Product Development Dept. of Dalmia Bharat Cement, shares insights with readers of Indian Cement Review on why and how to restrict magnesia content. Excerpts from the interview.

All hydraulic cements have the cementatious compounds alite, belite, celite and ferrite, commonly called as phase components, in them.

These phase components constitute major proportion of OPC (85 to 92 per cent ) and they impart cementaitious properties to it. However, cement contains some minor unwanted constituents, too. Some of these adversely impact the quality and one such deleterious constituent in cement is magnesium oxide, present in the form of periclase. Magnesium oxide (magnesia) content in cement should be as low as possible.

How does magnesia enter the product?

This unwanted component normally finds its way into cement through limestone, which is the principal raw material in the cement manufacture. During pyro-processing of the raw meal (mixture of pulverised raw materials in the desirable proportion) and the air quenching of the resultant clinker, magnesia molecules exhibit a tendency to cling together and form macro-crystals known as periclase. This happens especially if the cooling of the clinker is insufficient.

What are the adverse effects of periclase?

Periclase has the unique property of remaining dormant in concrete for a long time, while other components get hydrated. Periclase crystals do not react with water easily in the normal hydration process, but gets activated after about five years or so and undergoes hydration forming expansive magnesium hydroxide. Magnesium hydroxide occupies more volume and puts stress on the hardened concrete. This leads to cracks in the concrete structure. As time goes by, these cracks grow deeper, causing leakages in or irreparable damage to the structure. Magnesia is one of the major culprits behind late expansion cracks in concrete.

Does it affect the compressive strength?

Yes, it does. Its presence in the raw material hinders the proportionate formation of useful phase components and consequently, it reduces the potential compressive strength of the concrete.

What is the safe limit set for magnesia content?

As there is a great threat to the safety of construction with high magnesia cement, the Bureau of Indian Standards has restricted the magnesia content to a maximum of 6 per cent in cement. The BIS limit of 6 per cent is justified only on the consideration that the technology involved in India is most modern. It assumes that plants will have high efficiency coolers to quench the clinker rapidly, and freeze the magnesia minerals into microcrystalline form or disperse them. However, cement plants that do not have these facilities or are operating at above the rated capacity, carry the risk of periclase formation. Periclase formation can occur if magnesia content is higher than 2 per cent. Besides this, operational inadequacy or shortage of cooling fans could lead to periclase crystals formation. This can occur even at lower levels of 3 to 5 per cent magnesia. Regrettably, the 6 per cent limit is not always safe for concrete. We can conclude that magnesia content below 2 per cent could help avoid the risk of periclase formation, even if the cooling is inadequate at times.

Tell us about magnesia content in your products.

The magnesia content in all Dalmia cement products marketed across the southern states of India is hardly 1.2 per cent. Limestone reserves judiciously acquired by Dalmia in the 1930s contain a negligible amount of magnesia. So the cement products manufactured from these raw materials are completely safe and carry no risk of late concrete expansion crack development. Moreover, the pyro-processing facilities and coolers at Dalmia are most modern, ruling out any possibilities of periclase macro crystals formation. This certainly is an important USP of Dalmia products and one that separates our offerings from competing products.

What is your take on the BIS’ move restricting the magnesia content to a maximum of six per cent?

We accept BIS move on restriction of magnesia to max of 6 per cent in OPC to avoid failure of concrete structures because of expansion due to high magnesia.

What are the adverse impacts of high per cent of magnesia in cement on concrete?

Excess quantity of magnesia affects the Soundness of Cement. Free uncombined magnesia trapped inside the crystals of the silicates, hamper this as these compounds expand considerably on hydration and their hydration itself commences after a considerable time lag with respect to that of the other compounds.

How successfully have you addressed this issue?

Effect of high magnesia can be minimise by fast cooling clinker to avoid formation of magnesia crystals and keep it in glassy form. All the grades of cement offered by KCP contain less than 6 per cent of magnesia due to usage of low magnesia raw materials.

Does high content of magnesia have any impact on the compressive strength of concrete?

Yes, Due to change in geometric volume of concrete due to expansion, concrete loss its strength.

Tell us whether the use of low content magnesia has any contributory role in the durability of a concrete structure?

Yes. Due to formation of expansion cracks in concrete due to volume expansion of magnesia, the durability of concrete will be very poor.

At higher temperature of clinker from cooler discharge the MgO remains in periclase form, resulting in expansive cement. On the other hand if proper quenching at cooler occurs the MgO changes to glass phase with no expansion. So MgO remains in periclase it will affect the concrete volume stability. Entire VC Limestone deposit is of very low MgO, all the grades of cement offered by Vasavadatta Cement contain less than one percent of magnesia. The use of low content magnesia always contributes for durability of concrete. – CK Jain, Unit Head, Vasavadatta Cement

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Price hikes, drop in input costs help cement industry to post positive margins: Care Ratings

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Region-wise,the southern region comprises 35% of the total cement capacity, followed by thenorthern, eastern, western and central region comprising 20%, 18%, 14% and 13%of the capacity, respectively.

The cement industry is expected to post positive margins on decent price hikes over the months, falling raw material prices and marked drop in overall production costs, said an analysis of Care Ratings.

Wholesale and retail prices of cement have increased 11.9% and 12.4%, respectively, in the current financial year. As whole prices have remained elevated in most of the markets in the months of FY20, against the corresponding period of the previous year.

Similarly, electricity and fuel cost have declined 11.9% during 9M FY20 due to drop in crude oil prices. Logistics costs, the biggest cost for cement industry, has also dropped 7.7% (selling and distribution) as the Railways extended the benefit of exemption from busy season surcharge. Moreover, the cost of raw materials, too, declined 5.1% given the price of limestone had fallen 11.3% in the same aforementioned period, the analysis said.

According to Care Ratings, though the overall sales revenue has increased only 1.3%, against 16% growth in the year-ago period, the overall expenditure has declined 3.2% which has benefited the industry largely given the moderation in sales.

Even though FY20 has been subdued in terms of production and demand, the fall in cost of production has still supported the cement industry by clocking in positive margins, the rating agency said.

Cement demand is closely linked to the overall economic growth, particularly the housing and infrastructure sector. The cement sector will be seeing a sharp growth in volumes mainly due to increasing demand from affordable housing and other government infrastructure projects like roads, metros, airports, irrigation.

The government’s newly introduced National Infrastructure Pipeline (NIP), with its target of becoming a $5-trillion economy by 2025, is a detailed road map focused on economic revival through infrastructure development.

The NIP covers a gamut of sectors; rural and urban infrastructure and entails investments of Rs.102 lakh crore to be undertaken by the central government, state governments and the private sector. Of the total projects of the NIP, 42% are under implementation while 19% are under development, 31% are at the conceptual stage and 8% are yet to be classified.

The sectors that will be of focus will be roads, railways, power (renewable and conventional), irrigation and urban infrastructure. These sectors together account for 79% of the proposed investments in six years to 2025. Given the government’s thrust on infrastructure creation, it is likely to benefit the cement industry going forward.

Similarly, the Pradhan Mantri Awaas Yojana, aimed at providing affordable housing, will be a strong driver to lift cement demand. Prices have started correcting Q4 FY20 onwards due to revival in demand of the commodity, the agency said in its analysis.

Industry’s sales revenue has grown at a CAGR of 7.3% during FY15-19 but has grown only 1.3% in the current financial year. Tepid demand throughout the country in the first half of the year has led to the contraction of sales revenue. Fall in the total expenditure of cement firms had aided in improving the operating profit and net profit margins of the industry (OPM was 15.2 during 9M FY19 and NPM was 3.1 during 9M FY19). Interest coverage ratio, too, has improved on an overall basis (ICR was 3.3 during 9M FY19).

According to Cement Manufacturers Association, India accounts for over 8% of the overall global installed capacity. Region-wise, the southern region comprises 35% of the total cement capacity, followed by the northern, eastern, western and central region comprising 20%, 18%, 14% and 13% of the capacity, respectively.

Installed capacity of domestic cement makers has increased at a CAGR of 4.9% during FY16-20. Manufacturers have been able to maintain a capacity utilisation rate above 65% in the past quinquennium. In the current financial year due to the prolonged rains in many parts of the country, the capacity utilisation rate has fallen from 70% during FY19 to 66% currently (YTD).

Source:moneycontrol.com

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Wonder Cement shows journey of cement with new campaign

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The campaign also marks Wonder Cement being the first ever cement brand to enter the world of IGTV…

ETBrandEquity

Cement manufacturing company Wonder Cement, has announced the launch of a digital campaign ‘Har Raah Mein Wonder Hai’. The campaign has been designed specifically to run on platforms such as Instagram, Facebook and YouTube.

#HarRaahMeinWonderHai is a one-minute video, designed and conceptualised by its digital media partner Triature Digital Marketing and Technologies Pvt Ltd. The entire journey of the cement brand from leaving the factory, going through various weather conditions and witnessing the beauty of nature and wonders through the way until it reaches the destination i.e., to the consumer is very intriguing and the brand has tried to showcase the same with the film.

Sanjay Joshi, executive director, Wonder Cement, said, "Cement as a product poses a unique marketing challenge. Most consumers will build their homes once and therefore buy cement once in a lifetime. It is critical for a cement company to connect with their consumers emotionally. As a part of our communication strategy, it is our endeavor to reach out to a large audience of this country through digital. Wonder Cement always a pioneer in digital, with the launch of our IGTV campaign #HarRahMeinWonderHai, is the first brand in the cement category to venture into this space. Through this campaign, we have captured the emotional journey of a cement bag through its own perspective and depicted what it takes to lay the foundation of one’s dreams and turn them into reality."

The story begins with a family performing the bhoomi poojan of their new plot. It is the place where they are investing their life-long earnings; and planning to build a dream house for the family and children. The family believes in the tradition of having a ‘perfect shuruaat’ (perfect beginning) for their future dream house. The video later highlights the process of construction and in sequence it is emphasising the value of ‘Perfect Shuruaat’ through the eyes of a cement bag.

Tarun Singh Chauhan, management advisor and brand consultant, Wonder Cement, said, "Our objective with this campaign was to show that the cement produced at the Wonder Cement plant speaks for itself, its quality, trust and most of all perfection. The only way this was possible was to take the perspective of a cement bag and showing its journey of perfection from beginning till the end."

According to the company, the campaign also marks Wonder Cement being the first ever cement brand to enter the world of IGTV. No other brand in this category has created content specific to the platform.

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In spite of company’s optimism, demand weakness in cement is seen in the 4% y-o-y drop in sales volume. (Reuters)

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Cost cuts and better realizations save? the ?day ?for ?UltraTech Cement, Updated: 27 Jan 2020, Vatsala Kamat from Live Mint

Lower cost of energy and logistics helped Ebitda per tonne rise by about 29% in Q3
Premiumization of acquired brands, synergistic?operations hold promise for future profit growth Topics

UltraTech Cement
India’s largest cement producer UltraTech Cement Ltd turned out a bittersweet show in the December quarter. A sharp drop in fuel costs and higher realizations helped drive profit growth. But the inherent demand weakness was evident in the sales volumes drop during the quarter.

Better realizations during the December quarter, in spite of the 4% year-on-year volume decline, minimized the pain. Net stand-alone revenue fell by 2.6% to ?9,981.8 crore.

But as pointed out earlier, lower costs on most fronts helped profitability. The chart alongside shows the sharp drop in energy costs led by lower petcoke prices, lower fuel consumption and higher use of green power. Logistics costs, too, fell due to lower railway freight charges and synergies from the acquired assets. These savings helped offset the increase in raw material costs.

The upshot: Q3 Ebitda (earnings before interest, tax, depreciation and amortization) of about ?990 per tonne was 29% higher from a year ago. The jump in profit on a per tonne basis was more or less along expected lines, given the increase in realizations. "Besides, the reduction in net debt by about ?2,000 crore is a key positive," said Binod Modi, analyst at Reliance Securities Ltd.

Graphic by Santosh Sharma/Mint
What also impressed analysts is the nimble-footed integration of the recently merged cement assets of Nathdwara and Century, which was a concern on the Street.

Kunal Shah, analyst (institutional equities) at Yes Securities (India) Ltd, said: "The company has proved its ability of asset integration. Century’s cement assets were ramped up to 79% capacity utilization in December, even as they operated Nathdwara generating an Ebitda of ?1,500 per tonne."

Looks like the demand weakness mirrored in weak sales during the quarter was masked by the deft integration and synergies derived from these acquired assets. This drove UltraTech’s stock up by 2.6% to ?4,643 after the Q3 results were declared on Friday.

Brand transition from Century to UltraTech, which is 55% complete, is likely to touch 80% by September 2020. A report by Jefferies India Pvt. Ltd highlights that the Ebitda per tonne for premium brands is about ?5-10 higher per bag than the average (A cement bag weighs 50kg). Of course, with competition increasing in the arena, it remains to be seen how brand premiumization in the cement industry will pan out. UltraTech Cement scores well among peers here.

However, there are road bumps ahead for the cement sector and for UltraTech. Falling gross domestic product growth, fiscal slippages and lower budgetary allocation to infrastructure sector are making industry houses jittery on growth. Although UltraTech’s management is confident that cement demand is looking up, sustainability and pricing power remains a worry for the near term.

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