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Complying with revised emission norms: The cost-effective way

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This article covers experiences about NOx reduction in Europe, USA and China as well as the challenges and opportunities to comply with the revised emission norms in a cost efficient way

The Indian Ministry of Environment had on August 25, 2014 published new nitrogen oxide (NOx) emission limit values for the cement industry. It means rotary kiln plants commissioned before the date of notification have to comply with a new NOx emission level value of maximum 800 mg/Nm3 dry flue gas at 10 per cent O2, measured as NO2. For plants commissioned on or after the date of notification, the ELV is 600 mg/Nm3. There have been discussions between the cement industry and the ministry. The final outcome regarding the NOx levels and date for compliance was not yet official at the time of writing this article.

This article covers experiences from NOx reduction in other parts of the world such as Europe, USA and China as well as the challenges and opportunities to comply in a cost efficient way. Some of the points being discussed are:

  • Emissions levels in other countries and how the cement industry has coped with the legislation
  • Technology solutions – SNCR, SCR
  • Process requirements
  • Choice of reagent (ammonia solution or urea) related to efficiency, safety, availability and sourcing
  • CAPEX and OPEX

NOx emission limit values in India
The new emission limit values in India were published on August 25, 2014. Table-1 is an extract from the notification from the ministry.

All monitored values for NO2 shall be corrected to 10 per cent oxygen and on dry basis. After some initial uncertainties, it has been clarified that the NOx values are to be measured as 24-hour average values. The industry has also been given an extension of the time to comply. According to the author?s understanding, 18 months after September 2015 if the plant can give proof of having started activities with the aim to reduce the NOx.

NOx emission limit values in Europe
Refer to Table-2, which is showing the present NOx emission regulation in the European Union. The values are given as Associated Emission Levels (AEL), associated with the Best Available Technique (BAT). The BAT and the AEL are set by the European Union and it also takes into account what is reasonable economically. The most common applicable AEL for traditional pre-calciner clinker plants is today 500 mg/Nm3. But more and more alternative fuels are being used. The ELV for waste to energy plants is 200 mg/Nm3 @ 11 per cent O2. This means that cement plants having a certain amount of waste as fuel, will have to comply with 200 mg/Nm3. Yara Environmental Technologies has been and is involved in several projects for exchanging or converting old SNCR systems to new high performance systems that are able to reduce the NOx down to 200 mg/Nm3. To reach these high reductions of sometimes 80-90 per cent with SNCR, ammonia solution has to be used. Using urea, reductions over 50 per cent in most cases cannot be reached.

SCR in the cement industry
SNCR has been the totally dominant deNOx method in the cement industry. A small number of SCR (Selective Catalytic Reduction) systems has however been installed. The main reasons for this seem to have been:

  • Several times higher investment than SNCR, large footprint and installation complications.
  • Operational costs can be lower compared to standard SNCR systems using urea. But compared to high efficiency SNCR systems using ammonia, there hasn?t been any OPEX advantage.

The main operational cost for SCR is still the ammonia or the urea, even if the chemical efficiency is higher for SCR than for SNCR. To this comes the catalyst cost, which is a big part of the operational costs. It includes regular regeneration of the catalyst and replacement with new catalyst after some years of operation. The electrical power is also much higher for SCR, 2-5 kWh per ton clinker. This comes mainly from increased fan consumption due to pressure drop over the catalyst and from dust cleaning when running high dust SCR.

The SNCR process
The SNCR process is a process of chemical reactions taking place very soon after the combustion. The main reaction is NH3 + NOx ? N2 + H2O (Simplified formula). To be efficient, it requires a certain temperature window. For ammonia it is between 970 – 850?C; for urea it is 1100 – 950?C. This is one of the reasons why ammonia is much more efficient than urea in pre-calciners and pre-heaters. So for an efficient reduction and low reagent consumption, it is important to install a certain number of injectors at the right locations GC? typically, somewhere between the kiln inlet and the last cyclone but after secondary combustion. Refer to Figure-3 If injection is done at a very high temperature, more NOx will be formed. Injection at low temperatures will create ammonia slip. Both result in unnecessary consumption of reagent.

The SNCR system and its components
Figure-4 shows the main parts and flow of an SNCR system. An SNCR system normally consists of the following main parts:

Storage tank
The tank can be a single wall or double wall type and it should be manufactured in stainless steel. The single wall tank will require a retention bund in concrete around the tank to capture any possible leaks. The tank is designed for pump filling from a tank lorry and with a return line for displaced gas back to the tank lorry. The tank has to have certain instruments like overfill protection, pressure/vacuum valve with flame arrestor, leakage indicator, level transmitter for indication of the tank volume and a tank pressure transmitter.

Emergency shower
The emergency shower should be a combined drench shower and eye/face wash for installation outdoors close to the storage tank for reduction agent and filling point.

Pump module for filling of the storage tank
The pump module is for filling of the reduction agent, from a tank lorry without own pump, into the storage tank. The pump module will be located outdoors near the storage tank.

Pump module for reduction agent
The pump module is for transporting and pressurising reduction agent from storage tank to the process units. The pump module is normally located outdoors close to the storage tank.

Pump module for softened water
There should also be a pump module for transporting and pressurising softened water. For some applications with low reagent consumption, it is needed for dilution of the reduction agent solution to the concentration needed in the furnace. The water is pumped to the process unit where it is blended with the reagent. For cement applications, the consumption of reagent is normally quite high and thus no dilution water is needed. But it will still be needed for the flushing of the system when the system is stopped for maintenance, etc.

Process unit
The process unit should be located as close as practically possible to the injection area. The unit includes one blending module and injection modules, one for each injector. The blending module produces the required quantities of reduction agent for the current operating condition demands and each injector module manages one injector. The injector module is equipped to open and close reduction agent flow, manage atomising and cooling air and purging with water when stopped. The unit includes all necessary valves, flow transmitters and pressure transmitters for automatic operation.

The unit is also equipped with a gas alarm, giving a light signal and sending an alarm to the control unit at moderate gas concentration of ammonia. If level of ammonia gas is high the complete SNCR system will be stopped automatically. The process unit communicates with the control and management module, normally via Profibus DP to distributed I/Os.

Injectors
The special injectors developed by Yara are manufactured in stainless steel and managed from the process unit. The spraying length and width as well as the size of the droplets are adjustable. The possibilities of adjustments give a broad flexibility and means that the spraying dose can reach a large area of the ducting. Compressed air is used to atomise the droplets of reduction agent. For injectors in stand-by the compressed air is used for cooling of the injector. When the injection is stopped the injectors will be purged with softened water to secure that no reduction agent is left in the system.

Control and management module
The control and management module is equipped with PLC intelligence of well-known brands and distributed I/Os that normally communicate via Profibus DP. CMM controls, manages, co-ordinates and monitors all process functions to an automatic controlled system. It communicates with the superior control system (DCS) of the plant, receives signals from the plant, takes care of the recipe arithmetic, calculates set points for the reduction process and communicates with operator interface. The local operator interface (HMI) is an industrial PC and a touch screen. All commands to the system are given through the operator terminal. Process pictures are used for operation and management of the system. The pictures make the operation easy since commands often are given by pushing buttons on the touch screen. The control panel also collects and stores the process information. Necessary process data shown in the operator terminal can be transferred to the superior control system (DCS) of the plant for normal operation/supervision. The normal daily operation and supervision of the system is made from the DCS of the plant. The system can be equipped with a VPN connection for remote control, trimming and supervision by Yara.

Installation and commissioning.
The installation works on site require piping for reagent, water and compressed air between the modules. The pipes for the reagent shall be made in stainless steel. The electrical works are limited to power connection of the modules and communication cables between them and to the DCS.

Ammonia or urea?
So far there are two different types of reagents that have been used in SNCR systems.

  • Ammonium hydroxide – NH4OH, also named ammonia solution or aqueous ammonia. The concentration is commonly 25% due to hazard classification and safety and transport regulations.
  • Urea – NH2CONH2 is used in different concentrations, typically from 30 – 40 per cent. It?s most commonly delivered in liquid form in tank trucks to the cement plant. Some plants are receiving dry urea and have on site a dissolving station, mixing the dry urea with warm and softened water. The dry urea can be delivered in bulk or in big bags. The urea has to be of technical grade. Fertiliser grade may have impurities that can jeopardise the functioning of the SNCR system.

Which one to use?
There are several aspects to take into account when choosing the reagent.

  • The availability and price of product. Transport cost can be a significant part of the price for long transport distances.
  • The reduction needed. With urea, reductions of 20-50 per cent are possible depending on the process conditions. With ammonia, much higher reductions can be reached; even up to 90 per cent if the process conditions are the right ones.
  • The chemical efficiency and its effect on the OPEX. Ammonia is about 2-3 times more efficient than urea. This is based on a large number of comparative test injections done by Yara, refer to Figure-5.
  • Ammonia slips requirements. Urea gives higher ammonia slip than ammonia.
  • Urea gives higher emission of laughing gas (N2O) than ammonia. Laughing gas is a greenhouse gas, 300 times more potent than CO2.
  • A flexible SNCR system that can run on both ammonia solution and urea solution, will give flexibility in the use of reagent depending on variation in supply and price conditions.
  • Local safety regulations and permissions for storage and handling.

CAPEX and OPEX
Below, see Table-6, are two examples showing the investment and the annual operational costs for a typical SNCR installation at a cement clinker plant at two different NOx reduction rates. The estimations are based as far as possible on conditions in India.

The first example is with a NOx reduction from 1200 to 800 mg/Nm3 dry at 10% O2 and the other example from 1000 to 800 mg/Nm3. Typical comparison between 25 per cent ammonia solution and 40 per cent urea solution is done.

From the examples it is clear that the dominant cost is by far the consumption of reagent. And ammonia solution gives a substantially lower cost than urea due to its normally much higher efficiency.

It can also be noted that the annual OPEX is on the same level as the total investment. So in order to minimise the OPEX, the design and installation of the SNCR is worth paying careful attention to. An SNCR installation which has an efficiency of, 20 per cent more than another one, will quickly offset a possible higher investment.

Some of the main factors that make an SNCR installation efficient are:

  • The right number of injectors at the right locations that have the most favorable process conditions.
  • The number of injectors and their locations should also give flexibility for changes of fuel and changes in the process.
  • Injector design.
  • The control system and its software. It should be totally automatic and quickly respond to the variations in NOx and other conditions.
  • The experience of the SNCR supplier

High performance SNCR

  • Possibility of high NOx reduction, up to 80 GCo 90 per cent is possible.
  • High chemical efficiency, minimisation of the consumption of reagent which is the major operational cost for running a cement plant SNCR.
  • Reliable system with high availability.
  • High safety standard with ATEX certificates and SIL classification.

This article has been authored by CH Persson, Yara Environmental Technologies AB, Sweden

Table-1 NOx emission limit values in India

S" No. Industry Parameter Standards
(1) (2) (3) (4)
"10 Cement Plant
(without co-
processing),
Stadalone
Clinker Grinding
Plant or Blending
Plant		 A – Emission Standards
  • Rotary Kiln – without co-processing
Date of
Commissioning		 Location Concentration not to
exceed, in mg/Nm3
(a) (b) (c)
Nitrogen Dioxide
(NO2)		 on or after the date
of notification		 anywhere in the
country		 600 (with effect from 01.06.2015)
before the date of notification anywhere in the
country		 800 (with effect from 01.01.2016)

Table-2 NOx emission limit values in Europe

Cement plants Unit BAT-AEL (daily average) Before
Preheater kilns mg/Nm3 <200 – 4502) 3) 800
Lepol and long rotary kilns mg/Nm3 400 – 8001) 800
1) Depending on initial levels and ammonia slip.
2) BAT-AEL is 500 mg/Nm3, where after primary measure/techniques the
initial NOx is > 1000 mg/Nm3.
3) Existing kiln system design, fuel mix properties including waste, raw material burn ability can influence the ability to be in the range.

Table-6 OPEX and CAPEX examples OPEX and CAPEX

Data Example 1 Data Example 1 Costs INR/year Example 1 Costs INR/year
Example 2
Clinker production 4300 ton/day
Production hours 8000 h/year
Flue gas flow 400 000 Nm3/h
Base NOx 1200 mg/Nm3 1000 mg/Nm3
NOx with SNCR 800 mg/Nm3 800 mg/Nm3
25% ammonia consumption 397 kg/h 199 kg/h
Price 20 000 INR/ton 63 520 000 31 840 000
40% urea solution consumption 1025 kg/h 532 kg/h
Price 20 000 INR/ton 164 000 000 85 120 000
Compressed air 40 m3/h 30 m3/h 400 000 300 000
Soft water for flushing Only occasionally 50 000 50 000
Power for SNCR 3 kW @ 10 INR/kWh 240 000 240 000
Wear parts 100 000 80 000
Maintenance 20 man-hours x 500 10 000 10 000
TOTAL ANNUAL OPEX WITH AMMOMIA 64 320 000 32 520 000
INR per ton clinker 45 22
TOTAL ANNUAL OPEX WITH UREA 164 800 000 85 800 000
INR per ton clinker 113 59
TOTAL CAPEX SNCR INCL PROJECT COSTS 50 000 000 45 000 000

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

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October 21, 2021

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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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October 21, 2021

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

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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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