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Build ups in pyro-processing

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It is a common problem to face build ups in the cement making process. The difficult ones are in pyro process, because you have to deal with high temperatures and unsafe conditions. It is always a challenge for plant management to handle such situations.

Undoubtedly pyro processing is the most important part of cement manufacturing. It is high energy intensive next only to grinding. However the pyro process faces some problems like jamming due to build ups. Let us look into some of the causes of build ups.

Generally these build ups are hurdles in the smooth running of plant. Sometimes these even turn out to hazards for safe working. It is necessary to go to the root cause of the build up formations. Though each and every build up can be attributed with a specific cause yet there are some common causes which can be viewed as generic problems.

The most common problems of build up formation are… "Snowman", "Rhino horn", and "Boulder", Red River in kiln system. We shall discuss about few of those. The first two build ups are formed from small clinker nodules and clinker dust particles. Their chemical and mineralogical composition is identical to clinker, but in some cases enrichment up to 3.5 percent K20 and 3.0 percent S03 has been noticed. Snowman is a formation of large build-up on cooler first grate (static grate) or kiln discharge wall where the clinker falls from the kiln. Snowman may eventually grow to reach the mouth of the kiln, thereby blocking the discharge of clinker from the kiln.

Snowman causes poor clinker distribution thereby poor heat exchange between clinker and secondary air. Snowman formation mechanism may divide to two:

1)Freezes of the clinker liquid phase as the clinker passes through the first cooling zone in the rotary kiln or on falling down the chute into the grate cooler. The clinker dust particles carried back by the secondary air stream from the clinker bed grate into the interior of the rotary kiln also play an important role on formation snowmen. The clinker dust particles, having a superficial liquid phase layer, strike against the chute wall and the refractory lining at what is the formation mechanism of "Snowman", "Rhino horn", and "Boulder" in kiln system?

2).Occasionally large lumps of coating discharge from the kiln, these lumps of kiln coating act as "seeds" for the formation of snowman. Snowman form when fines fall from the kiln onto the top surfaces of these lumps, on top of the clinker bed within the cooler. As layer after layer of the fines fuse onto the lump, snowmen "grow" upwardly into stalagmite-like structures.

Rhino horn: is a build-up on the top of kiln burner pipe. Rhino horn formation mechanism: Clinker dust carried back to the kiln with the secondary combustion air loses velocity around the burner and that causes clinker dust to settle and build up on the top of the burner.

Boulder: Generally, clinker ball/ boulder formation is related to low clinker SM with high AM or related to very thick coating. Figure is showing a boulder with 1.80 m in diameter.

Boulder formation mechanism: Large clinker balls initiate and grow behind a thick coating or ring. Build up often fall and slide into the kiln as large slabs and coming to rest behind a ring (if it is large enough). The slab can roll around behind the ring forming a ball which can then grow larger due to accretion.

Snowman formation
Dusty clinker melts due to alkali or sulphur recycle distorted flame disintegration of clinker due to reduced conditions. Blow back of dust from cooler to kiln and recycling high air flow rate in first portion of clinker When the kiln is dusty the snow man problem is common. The dust falls on the cooler and blows back into the kiln which is carried away by secondary air stream. If secondary velocity is more than 5 m/s the finer dust is carried into the kiln and the velocity of combustion air and combustion products further shoots up near the flame which carries the dust further inside the burning Zone. This dust steals some liquid from the burning zone and falls on the cooler and the cycle continues between cooler to kiln. It reaches a stage when the clinker dust becomes so sticky that it sticks to the side and vertical wall of the cooler and dust build – up called snow man forms. If sulphur and alkali recycle is there inside the kiln the melt increases, which do not reflect in the calculated liquid, the minor low melting compounds concentrate more on dusty fraction of the clinker. Some critical parameters can be controlled by operating the kiln with good quality liquid and good flame with oxidised conditions. A short radiant flame forms relatively better clinker. A long flame increases the burning zone length which allows the low melting constituents to volatilize and recycle.

It is often misunderstood that long flame gives good refractory life and hence to form a lazy flame . This makes the kiln more dusty. The momentum for conventional burner is totally different from the multi channel burner. The momentum is maintained to improve the rate of mixing of coal and combustion air, there by improve the combustion efficiency. The momentum with low primary air percentage and high velocity is much better than with high Primary air and low velocity. The shorter black jet (plume) and good radiant convergent flame make the kiln much efficient. The flame is the victim of many hands and so the kiln. Flame has to be monitored often and so the shell temperature which is good reflection of the good shaped flame.

If flame is wrong everything goes wrong . We immediately blame the chemistry and demand more liquid to form good nodules which aggravates the situation. If coal falls on the charge, the liquid quality changes One thing we have to remember is that with a good flame, short radiant flame we can reduce the liquid percent. Short radiant flame gives dense and better shaped nodules than long lazy flame.

Why the dust blow back? The dust is the main culprit of the snowman formation and then the uneven distribution of air further aggravates the situation. The red river area is aerated more, the dust Is blown back into the kiln. In modern beam aerated cooler the sandblasting effect must be low. If it is so then the cooler plates profile needs check. Air flow in the front portion of the cooler has to be redistributed to avoid blasting. More airflow does not mean more recuperation. Burner can be pushed inside the kiln by 500 to 1000 mm if there is margin in percent calcination. If calciner does not have margin it leads to loss of production. Avoid CO formation at any cost.

Source: Nael Shabana qatar.cement@yahoo.com

Compiled by VIKAS DAMLE

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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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