Waste heat recovery in cement plant - Indian Cement Review
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Waste heat recovery in cement plant

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It is an established practice to use alternate sources of energy to reduce cost of manufacturing. One of the proved practices is to have waste heat recovery system installed. Here is a case study with more details.

Energy is a major input in cement manufacturing process and is being met through captive power generation to run the operations cost effectively. On an average, energy cost is around 40 per cent of the production cost for cement manufacturing.

Cement plants in India have installed coal based captive power plants (CPP), which are in operation for several decades. Before this technology was introduced, 30 to 40 per cent of the heat generated in the cement rotary kiln and after quenching cooler (AQC) processes of a cement plant were wasted and therefore, efforts were made to use the waste heat productively to bring down the cost of production. As a part of this process, since 2002, cement facilities started adopting waste heat recovery systems for power generation.

Waste heat recovery (WHR) power plant installed in cement plants, use the heat generated through rotary kiln preheater (PH) and AQC exhaust hot gases for power generation. These hot gases are used to generate steam in steam generator (Boiler) which is further used to generate electricity/power through steam turbo generator (STG). Typically 20 to 30 per cent power requirement of the cement plant can be fulfilled using this waste heat for power generation application, which is a substantial savings/reduction in the overall cost of production.

The number of preheater stages in a cement plant has a significant bearing on waste heat recovery potential. A preheater tower is likely to have four to six stages. Aged plants have 4 and 5 stage heat recovery in the preheater and thus have a higher potential for power generation. If the numbers of preheater stages are more, efficiency of the cement plant increases but has less potential for WHR power generation. Mid-tapping of AQC is important since it offers higher thermal energy or higher gas temperature. The potential of power generation is 25 KWh/tonne to 45 KWh/tonne of clinker production.

There are three processes by which WHR0-based power plants are installed in a cement industry globally.

Steam Rankine Cycle System (SRC)
Organic Rankine Cycle System (ORC)
Kalina-based system

In India, SRC is widely used for WHR based power generation in cement plants. In SRC, exhaust gases from rotary kiln pass through preheaters (PH) and reach the preheater boiler. Similarly mid tapping from AQC induces hot gases to AQC boiler.

One cement kiln line requires 2PH boiler and 1 AQC boiler. These boilers, based on heat source, generate Medium Pressure (MP) steam of 12 Ata to 18 Ata at temperature of 340 to 450 degree Celsius and low pressure (LP) steam of 2 Ata to 3 Ata pressure and temperature of 175 to 195 degree Celsius. For such application, Injection condensing turbines are used. Injection condensing turbines use medium pressure (MP) steam as inlet to turbine and LP steam is injected at LP side of the turbine. After this, combined steam is expanded at LP/Exhaust side to 0.1 Ata or 0.2 Ata based on water cooled condenser and air cooled condenser options.

Steam generation from hot gases is an important engineering and design aspect. Leading Indian boiler companies have developed expertise in steam generation, across various variable situations. Similarly Injection condensing turbines developed by Triveni for different MP and LP steam combinations are successfully working across Indian Cement Industry. These indigenised steam turbines and boilers helps in eliminating the dependency on Chinese boilers and Chinese turbines which were earlier being used in many WHR plants. While more than 60 per cent of cement plants have adopted WHR-based power plants, larger cement companies are considering WHR power plants for their Greenfield projects.

Triveni Turbines has supplied and installed several injection condensing turbines for cement WHR plants across India. Detailed design consideration is vital in injection and admission zone. Triveni Turbines rotors are designed with higher stability to offset the excitation caused due to fluctuating injection steam loads. Turbine mid-section and LP section is subjected to cyclic fatigue loads induced by thermal cycle and flow variations. Design and engineering teams carry out CFD analysis and creep fatigue analysis to address these issues. This design philosophy has made the turbines made by Triveni, robust and efficient for cement WHR applications. Following are exclusive offerings of Triveni which makes it one of the preferred supplier for Cement WHR applications.

Integral Lube Oil tank: Triveni offer integral lube oil tank, for PHL and civil cost optimisation of TG house.
MRT: Triveni use live steam MRT for its turbines. Turbine is tested with live steam from boilers at Bengaluru works with job mounted turbo supervisory systems and woodward governor and gear box.
In-house manufacturing: Turbine components like blades, rotor, and casing are machined and manufactured and assembled in same work shop at Bengaluru.
Vaccum tunnel: High Speed Balancing of Turbine Rotor is done in "Schenk" Vaccum Tunnel at both Peenya and Sompura Works at Bengaluru.
Triveni gearbox: Gearbox is from Triveni (TEIL) Mysore Works. Assembly is done with gearbox. Turbine and gearbox is installed on the same baseplate and becomes one unit. No separate foundation for gearbox is required.
Some of our prestigious projects across cement WHR plants in India are:
Ultratech Cement
5 turbine orders – Dhar Cement Works, Hirmi Cement Works, Bela Cement Works, Rajashri Cement Works and Dala Cement Works. Dhar and Hirmi Cement TG sets are in operation. Other three are in execution.
Nuvoco Vistas (Previously Lafarge Cement)
3 installations – Arasmita Cement, Sonadih Cement, Chittorgarh Cement Works
Mangalam Cement – Kota Rajasthan
Prism Johnson Cement – Satna, Madhya Pradesh
Parashakti Cement (Andhra Pradesh)
Deccan Cement (Andhra Pradesh)
Samrat Cement (Nepal)
Dalmia Cement (Odisha)
Bhavya cement (Andhra Pradesh)
Penna Cement (Andhra Pradesh)

Site installations: Ultratech Cement – Dhar Cement Works (Madhya Pradesh) – 13 MW TG installation

Parashakti Cement (Andhra Pradesh) – 6.5 MW TG installation with axial flow exhaust.

WHR flow diagram

Typical Admission/Injection Cross Section of Triveni make Turbine

Article by Prashant Dhanpawde, Head of Western Region Operations for India. Triveni Turbines Ltd

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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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