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Rock Solid with Slag

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Slag as a replacement material in normal cement is as high as 50 per cent. The advantages of slag cement concrete are many over ordinary Portland cement concrete.

Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. However, slag can contain metal sulphides and elemental metals. Slag is generally used to remove waste in metal smelting.

In nature, iron, copper, lead, nickel and other metals are found in impure states called ores, often oxidised and mixed with silicates of other metals. During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. Slag is the collection of compounds that are removed.

In many smelting processes, oxides are introduced to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractory lining from excessive wear. Quicklime and magnesite are introduced in molten steel ore for refractory protection, neutralising the alumina and silica separated from the metal, and assist in the removal of sulphur and phosphorus from the steel.

Slag from steel mills in ferrous smelting is designed to minimise iron loss and mainly contains oxides of calcium, silicon, magnesium and aluminium. Any sandy component or quartz component of the original ore automatically goes through the smelting process as silicon dioxide.

As the slag is channelled out of the furnace, water is poured over it for rapid cooling, often from a temperature of around 1,430 ?C. The product so obtained is called granulated slag. This process causes several chemical reactions to take place within the slag, and gives the material its cementious properties.

The water carries the slag in its slurry format to a large agitation tank, from where it is pumped along a piping system into a number of gravel-based filter beds. The filter beds then retain the slag granules, while the water drains away and is returned to the system.

When the filtering process is complete, the remaining slag granules, which now give the appearance of coarse beach sand, can be scooped out of the filter bed and transferred to the grinding facility where they are ground into particles that are finer than Portland cement.

Slag as a material cannot be used as cement, but in the presence of lime, slag can become rock hard like cement. This property of slag is of interest to cement producers. Today slag as a replacement material in normal cement is as high as 50 per cent, which is the highest in any class of blended cement. There are many advantages of slag cement like excellent resistance to chemical attack, especially to chloride and sulphates. Therefore slag cement is the appropriate product to be used in marine atmospheres.

The advantages of slag cement concrete are many over ordinary Portland cement concrete. Today all over the world, coastal jobs are carried out only with slag cement concrete, especially the foundation jobs.

But slag cement has a few disadvantages like longer setting time and slow development of strength. Because of these reasons, cement users are sometime reluctant to use slag cement in routine jobs. However, through proper guidance from industry experts, the use of slag cement is now increasing.

Slag as a material also has many other applications other than usage in cement. Slag can also be used as aggregate in concrete.

There are two ways to make to make slag cement from slag, one is to grind clinker with slag and the other to grind slag and cement separately and then blend them together to get cement. A minimum of 50 per cent of slag is blended with clinker to make slag cement.

In the recent past, separate grinding of slag and cement is becoming more popular for the simple reason that energy required to grind slag is much higher than that of clinker. The wear properties of hardware are also higher for slag than that of clinker. A vertical roller mill is the most preferred equipment to grind either slag or slag cement. Brands like Loesche, Pfeiffer and FlSmidth-Atox have mastered the art of grinding slag in vertical roller mills.

Grinding-related parameters of blast furnace slag cements (BFC), such as bond grindability, specific rate of breakage and breakage distributions are determined by employing separate and inter-grinding modes. Strength tests are performed on mortar specimens made by BFC prepared by these modes of grinding to the same fineness. Overall results favour the use of separate grinding mode in view of lower specific energy consumption, ease of manufacture, higher addition of slag and more flexible product quality arrangement.

The best example of use of slag in concrete has been the Bandra-Worli Sea Link in Mumbai where near about 70 per cent of slag has been used to produce M60 grade of concrete. Similarly, worldwide, there have been many structures where slag has been a major component of concrete, apart from cement.

Today majority of slag is used domestically, barring some quantity that is exported to neighbouring countries. In the last decade or so, there have been attempts to use slag produced in other metal industries like copper, lead and zinc. A committee was formed by the Bureau of Indian Standards to look into the possibility of use of slag other than steel slag in cement.

The appointed committee studied materials like copper slag, lead-zinc slag (ISF Slag), LD slag from the iron & steel industry, Kimberlite tailings from diamond mines, steel slag from electric arc furnaces, ferro alloy slag, ferro chrome slag and spent fluidised catalytic cracking from Indian Oil Corporation. The task before the committee was to examine suitability of the materials for use as performance improver in OPC (up to 5 per cent maximum) and for production of PSC.

The committee examined suitability of all materials mentioned above. After detailed examination, only three materials having latent hydraulic properties were considered for replacing clinker either as performance improver in OPC or production of PSC.

The findings of the committee were submitted to BIS, and based on the recommendations, the bureau has permitted use of other type of slag (other than steel slag) to the extent of 5 per cent as performance improver. The three types of slag approved by the committee are:
i)Lead zinc slag (ISF slag) produced by Hindustan Zinc at Udaipur (the main producer in India);
ii)LD slag produced by Tata Steel, Bokaro Steel, Rourkela Steel, Durgapur Steel, Bhilai Steel and RINL Visakhapatnam (six main producers);
iii)Copper slag produced by Hindustan Copper, Hindalco Industries and Sterlite Industries (three main producers in India).
Tata Steel makes two types of steel slag, depending upon the production process of steel making: LD slag (Linz- Donawitz Converter) or BOF (Basic Oxygen Furnace) and EAF slag (Electric Arc Furnace). The marketable LD slag makes up about 10-15 per cent of the steel output. Primary steel manufacturers like SAIL, Tata Steel and RINL produce only LD/BOF slag while secondary producers produce EAF slag.
EAF slag was not found suitable by the BIS committee either as performance improver or for production of PSC. LD slag was found suitable only for use as performance improver in OPC.

In short, ISF slag, LD slag and copper slag have met all requirements for use as performance improvers in OPC (up to 5 per cent). Later on, BIS may take an appropriate view for formulating a new code. ISF slag is recommended for use as performance improver in OPC by the committee.

As detailed earlier, slag cement has a slow setting time, and this creates a problem in construction during winter. This problem can be addressed by adding some alkali activators in a limited dosage, but this process slightly increases production cost and makes the manufacturing a little cumbersome. In the journey towards ‘green cement’, slag as a material has tremendous potential, which will be exploited more in coming years as we understand materials better.

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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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