Thermax process heating solutions reduced carbon footprint- the plant is equivalent to carbon capture by 3 LAKH TREES!


AVT is a public limited company promoted by AV Thomas Group. AVT Natural Products Ltd (AVT NPL) is a venture promoted, as a strategic diversification from the traditional plantation business. Operating in line with its corporate signature, the company specializes in the extraction of colors and flavors from a natural source. The Group consists of diversified Business in Tea, Rubber, and Consumer Products viz. spices, food ingredients, and healthcare products.

AVT identified with Thermax on the shared belief towards dedication to the customer satisfaction and adherence to highest quality standards and gave us the contract for a Greenfield Boiler Project.


ComBlocUltra Biomass Boiler Model: CBRG100-Ultra with Reciprocating Grate using Lambion, GmbH Technology

CA strategic business unit offers packaged boilers, thermal oil heaters, waste heat recovery boilers, hot water, and air generators. These are available in modular construction as a standard package configuration or a custom design for specific requirements. Innovated by a strong R&D that focuses on customer applications, we offer a range of heating systems designed to combust a wide range of solid, oil & gas fuels including biomass and heavy liquid fuels.


Thermax proposed a briquette-fired boiler of 10 TPH@14 kg/cm2(g) ensuring energy (steam) delivered at an optimum price leveraging high-end automated biomass boiler installation. Combloc – a compact, plug & play modular construction boiler with fully automatic operation ensuring high efficiency. Thermax has offered OPEX proposition with BOO (Build-own-operate) model ensuring highest uptime at all time.


  • Model: CB Ultra- 100/14
  • Capacity: 10 TPH (F&A 100°C)
  • Type: Hybrid Water & Smoke Tube design Boiler with automated,air-cooled reciprocating combustor system of Lambion (German Technology)
  • Design Pressure: 14 kg/cm2
  • Operating Pressure: 9.5 kg/cm2


  • Optimum Cost-Effective Steam Price
  • Guaranteed Boiler Uptime & Efficiency throughout the Product Lifecycle
  • A significant decrease in SPM emissions
  • Dedicated biomass fuel supply chain
  • Ensuring consistent quality at the right price

Thermax supports ITC’s green initiative by offering 100% biomass-fired boiler ensuring cost saving up to 45%


Thermax is committed to ‘Conserving energy and preserving the environment’, two areas vital for the world. We support business establishments to be more energy efficient and environment-friendly.
Our legacy is enriched with the green effect projects for which we are the first choice for some of the global brands in the word. ITC Group which holds a market capitalization of 50 billion USD with a turnover of 8 billion USD crediting to their robust portfolio of traditional and Greenfield businesses is one such esteemed business alliance for Thermax process heating solutions.
The multi-business conglomerate encompasses various manufacturing plants across India and one of them is at Ranjangaon, Pune MH. This food production unit manufactures instant noodles and potato chips. A heating system is the heart of any food processing unit and ITC group partnered with Thermax for a robust heating system. ITC group’s association with Thermax was cemented with the commitment to supply a
heating system to fulfill their steam requirement for which three FO (Furnace oil) fired boilers were commissioned for the same.

Project Insights

In 2012 ITC was looking for expansion and was keen to have a greener, cost-effective fuel, they decided to go for 100% biomass briquettes fired boiler from Thermax. There were three main criteria’s for this project – 1) Uninterrupted steam supply, 2) fast response to fluctuating load and 3) high efficiency. As ITC was keen to have 100% biomass-fired unit the biggest challenge was maintaining steam-fuel ratio as the calorific value of fuel i.e. biomass briquettes changes drastically due to the variation in moisture content, bulk density, ingredients of briquettes etc. Thermax understood customer’s requirement and proposed a fully automatic CPRG (Combipac Reciprocating Grate) boiler with automatic fuel feeding system, air pre-heater, and economizer to ensure best in class efficiency with suitable equipment.

Innovative solution by Thermax

The solution provided by Thermax-CPRG (Combipac reciprocating grate) boiler which can provide 14000 kg per hour steam for high-pressure steam requirements in chips and noodles frying process. The boiler is designed to respond to sudden load changes which are typical for food processing industry. Thermax has proposed boiler with a unique offering of “moving floor” which saves space and has automatic fuel level controller. From the moving floor, the fuel is then sent to fully automatic fuel feeding system comprising of dosing bin and multi-screw fuel feeder. To ensure steam to fuel ratio of 5.0 Thermax has offered Lambion Reciprocating grate technology. Thermax has technology tie-up with Lambion who has over 100 years of experience in biomass firing solutions.

Reciprocating grate

Reciprocating Grate utilizes successive oscillation of grate linkage for the continuous movement of fuel; alternate movement of grate blocks pushes the fuel in the distinct combustion zones of a grate. This gives toppling action to the fuel particle and hence ensures complete combustion. This grate offers progressive combustion with distinct combustion zones. Relative motion between fuel bed and grate helps to deal with poor fuels up to 60% moisture content.

Energy efficient and low emission operation

High efficiency is an important aspect of achieving an energy efficient operation process of the chips and noodles frying process. Thermax offers both air pre-heater to preheat the combustion air up to 150°C and economizer ensuring the water is preheated up to 120° C. CPRG offers advantages like 100% combustion, highest uptime and efficiency and low emission. Thus the fuel consumption during steam generation is reduced drastically, and hence compared to FO fired boilers the fuel cost saving is 45%*

Positive impact

The flue gas exit temperature is at 100-120° C. The boiler achieves SFR of 5 and ash percentage is as low as 14-15%. The SPM level is as low as 28 ppm. In order to achieve optimum fuel consumption, an O2 controller is integrated into the plant. An oxygen probe measures oxygen continuously and compensates changes in air temperature and air pressure automatically. This optimizes the efficiency of the boiler and reduces the negative environmental impact at the same time.

Continues automation and reliability

The high degree of automation in the steam boiler plant provides comfort and safety to the boiler operator who can see complete process of the boiler from a system linked computer screen. The controller can also manage the equipment and other parameters like fuel feeding, feed water section, combustion manager, and flue gas section, making the boiler unit an automated, timely and reliable solution. This makes the entire plant operation automated and the process can be managed by limited no of people.

The result

The Adaptation of an efficient boiler system from Thermax and the change in fuel from FO (furnace oil) to biomass briquettes helped ITC to save fuel cost by 45%*. The PLC (programmable logic controller) system
continuously monitors the performance of boiler thus
ensuring safety and optimum performance. The proven
construction of combipac together with appropriate plant
equipment and reciprocating grate technology ensures
continuous and high steam quality for chips and noodles
frying process. Thermax’s service team ensures optimum
plant settings, a constantly high efficiency, very low
emission and longer life of the entire plant with their
regular maintenance services.

Thermax successfully commissioned a steam boiler at Govind dairy Phaltan

Thermax’s CPFD a multifuel Boiler is utilized by the dairy company throughout the year for consistent steam supply


Govind Milk and Milk Products Pvt. Ltd was set up at Phaltan, near Pune, The growth of the company also led to the socio-economic development in the geographical area in and around the company, At Govind, the best procurement and processing systems are employed to process milk and produce milk products. A fully integrated, processing unit with International standards, with the capacity to process in excess of 10 lac liters of milk every day, is currently in use in Phaltan.

Thermax’s association with Govind Dairy is since June 2014 when we received an inquiry for boiler and there were several levels of technical discussion with Govind Dairy team and there Consultant at Phaltan. Finally, we were able to convince them that technically an AFBC boiler is more appropriate for Govind airy against RG influenced by FV. The order was commissioned in August 2016 since then the steam boiler is running successfully without any complaints.


Our Heating system is required for Milk Powder plant which is a very critical application, the constant pressure of 16kg/cm2 is required at the inlet of the dryer to maintain good quality Milk powder. CPFD 160 / 21 kg-Cm2, F&A 100 DegC steam boiler was proposed after understanding customer’s steam consumption pattern in the process. This plant uses steam to manufacture various products like ghee, Pedha, Icecream, Paneer consuming steam as a standard requirement in the process. The most important heating process required in the whole dairy process is the pasteurization of the milk for which consistent steam is supplied by the Thermax boiler.



CPFD 16 TPH boiler ensuring energy (steam) delivered at an optimum price leveraging high-end automated boiler installation.Thermax has offered AFBC technology with air preheater recovery unit with 92 % efficiency.The fuel bed is fluidized by the injection of air from the bottom of the bed through a set of air nozzles. This results in very turbulent air and fuel mixing leading to very efficient combustion and heat transfer.This also results in the tumbling action of the fuel like a boiling fluid causing higher residence time or combustion. O2 emissions are approximately 6% and a Zironia based O2 analyzer is installed at the site for online Monitoring.


  • Govind Dairy team opened boiler first time after 6months to check for cleaning, however, found compete boiler system was clean. They have now started cleaning boiler only during annual IBR shut down/Inspection.
  • Optimum Cost-Effective Steam Price
  • Ensuring consistent quality at the right price
  • Guaranteed Boiler Uptime
  • Efficiency throughout the Product Lifecycle

Thermax Process heating solutions

A strategic business unit offers packaged boilers, thermal oil heaters, waste heat recovery boilers, hot water, and air generators. These are available in modular construction as a standard package configuration or a custom design for specific requirements. Innovated by a strong R&D that focuses on customer applications, we offer a range of heating systems designed to combust a wide range of solid, oil & gas fuels including biomass and heavy liquid fuels.

Green Steam Supply for Dairy Industry

Thermax Onsite Energy Solutions Limited

Biomass Boiler Installation at ITC, Munger – Dairy Plant

ITC Group is one of India’s foremost multi – business enterprise with a robust portfolio encompassing Fast
Moving Consumer Goods (FMCG), Hotels, Paperboards & Specialty Papers, Packaging, Agri-Business, and Information Technology.

In the modern dairy, steam is used in a variety of processes and to help maintain clean, sterile conditions. Steam is used because it is an efficient carrier of heat providing constant temperatures essential for achieving good quality of products.

Thermax Onsite Energy Solutions Limited (TOESL), a subsidiary of Thermax Limited, provides outsourced
utility delivery services based on the Build-Own-Operate (BOO) business model, enabling customers to optimize costs, reduce CO2 footprint and remain focused on their core business.


ITC uses steam in its Dairy plant for indirect heating for the following manufacturing processes:

  • Skimmed Milk Powder
  • Dairy Whitener
  • Ghee, and
  • In the process of Pasteurization

Of the above applications, major steam consumption is to produce powdered milk in the Spray Dryer.

Previously, TOESL had set up 2 biomass utility plants for steam supply under BOO model for Tobacco and
Snacks & Noodle plants of ITC. Having reaped the benefits from said projects, TOESL was re-approached by ITC Group for a Steam Supply proposition based on biomass as fuel for their first milk processing facility in Munger, Bihar. This facility is a part of customer’s CSR initiative to create sustainable livelihoods in villages through a livestock development program.

In a move to generate cost savings and to be carbon-positive, ITC chose TOESL offering of Biomass-fired
boiler and entered into a long term BOO/T based Steam Supply Contract, inked in September 2013.

TOESL now supplies green steam to ITC’s Tobacco, Food and Dairy businesses.


  • Fuel survey undertaken for the particular site location to identify biomass fuels available within a 300 km radius of the site, in the province of Bihar
  • Fuels identified: Paddy Husk Paddy husk is available throughout the year in and around the site location
  • Vendor development to establish fuel supply chain network from source to site
  • Evaluation of biomass price and available quantity over the course of a year


  • Study of load patterns of the process plant
  • Study of steam consumption by the processes – minimum, average and peak
  • Establish the minimum steam off-take
  • Evaluate space available on-site


  • Leverage state-of-the-art, multi-fuel technology by Thermax and provide optimized, highly efficient and sustainable offerings to the customer
  • Undertake detailed engineering to deliver customized high-end solutions


Install and commission the biomass-fired boiler along with boiler accessories, fuel and ash handling systems and air pollution control equipment


  • Undertake comprehensive O&M along with fuel, ash, chemicals, consumables and spares management
  • Deploy experienced and trained manpower
  • Routine regulatory compliance
  • Maximize uptime and operating efficiency
  • Online & remote performance monitoring


  • Biomass Fired Boiler having Fluidized Bed Combustion
  • Boiler Type: Horizontal Multi-tubular Shell Type Smoke Tube with Water Wall Furnace Boiler
  • Boiler Model: CPFD80
  • Boiler Capacity: 8 TPH F&A 100 °C
  • Boiler Design Pressure: 21 kg/cm 2 (g)
  • Primary Fuel: Paddy Husk


  • Customer invests in the civil foundations and structure for the utility plant
  • Complete capital expenditure of the equipment undertaken by TOESL
  • Agreement period of 10 years
  • Customer shall pay interest free security deposit at the time of signing of agreement which shall be
    refunded at the end of agreement period
  • Fuel is charged on a pass-through basis
  • Utility is charged as per off take
  • Utility costing is done on the basis of the minimum off take decided between customer and TOESL
  • Utility price reduction on consumption exceeding minimum off take
  • Guaranteed delivery of uptime


  • Cost reduction due to effective utility price
  • Sizeable carbon savings as against fossil fuel boiler
  • Guaranteed boiler uptime & efficiency throughout product lifecycle
  • Operational Excellence – uptime and efficiency delivered higher than committed
  • Downtime planned in conjunction with process plant shutdown
  • No investment in utility plant and machinery by customer
  • Minimal SPM through advanced APC equipment
  • Dedicated biomass fuel supply chain ensuring consistent quality at right price

On operation of biomass-fired boiler over the years, ITC-Munger Dairy Division has contributed to reduction in CO2 emissions of over 7740 tons as of January 2019.
(Biomass Boiler Plant commissioned in August 2015)

Thermax sets a record by commissioning a 40 TPH boiler in just 40 days for Pharmaceutical major in Indonesia.


Thermax’s esteemed customer PT Cheil Jedang alias CJ Bio awarded an order for a 40 TPH Bi drum boiler. Thermax successfully completed erection and commissioning of the entire plant within eight months against a typical duration of twelve months. The entire commissioning activity was completed within 40 days instead of a four-months usual period.

Project Insights



In appreciating Thermax’s work Mr. Mukh Mustain (Engg Construction Manager) from CJ Bio said that “Erection of the boiler was completed on account of Thermax’s proper planning, safety, and technical expertise.”. He specially mentioned the work that was done by Sateesh D, Vaibhav Mohite and Rakesh Kumar and their respective teams for ensuring timely installation and commissioning.

Thermax Experts

This feat was possible owing to the high-quality execution by Thermax experts that eliminated any extra time spent in rework. The entire project was completed in adherence to the highest standards of safety resulting in zero reported incidents.

A critical success factor was the collaboration between CJ Bio and Thermax. The client provided all necessary support with logistics, planning, and execution.

The early commissioning not only helped customers resume operations before stipulated time but also helped Thermax achieve higher efficiency and cost savings.

Thermax is proud to welcome another satisfied customer to its fold and looks forward
to a strong association with CJ Bio in the future.


Industry:Medical Centre
Status: Installed in 2010

Project Snapshot

Client : Chromasun
End Customer : Crow Canyon Medical Center (CCMC)
Location :  Danville, CA, USA
Total capacity : 50 TR (175 kW)
Application : Air-conditioning at Medical Centre
Energy Source : 338°F hot water heated by solar ray
Chilled In/Out : 66°F/54°F (19°C /12°C)

Project Overview

Thermax’s installation at a medical centre located in California is the first solar thermal system to provide air cooling and heating, and domestic water heating for a U.S medical facility. Here,50 TR high temperature hot water is driven in the two stage chiller with back-up firing option has been installed at facility to cool the office area of 64,000 sq. ft. It is a complete energy efficient heating and cooling system which uses solar energy to generate the hot water.

Project Description

A primary business goal for our client was to operate one of the most energy-efficient and environmentally sustainable buildings showcasing the potential of solar thermal technology to offset both cooling (electricity) and water heating (natural gas) in the U.S. hospital industry. The medical centre has 75 Chomasun MCT of 3352 sq. ft. collector area total which gives hot water of 338°F which gives energy to run the 50 TR chiller delivering 54°F water. This water is circulated to cool the air for comfort cooling in the office area of 64,000 sq. ft. thus saving 145 MW-hr of electricity per year. It reduces carbon emission by 102 tons per year which is equivalent to the emission from 26 cars.


-By installing Thermax’s chiller, our client was able to make savings in power of about 145 MW-hr/year.

-We also helped them in the reduction of carbon emissions of about 102 Tons/year which is equivalent to the emission from 26 cars.

Thermax’s Biomass boiler commissioned at Serum Institute is a boon for saving the environment and reducing fuel cost by 30%.


Thermax is committed to conserving energy and preserving the environment, two areas critically monitored globally. We support businesses with 100% biomass-fired boilers ensuring fuel savings with lower emissions. Serum Institute of India is one such esteemed customer benefiting from green energy since 2013.

Saving the world with one vaccine at a time- Serum Institute of India Pvt. Ltd. is now the world’s largest vaccine manufacturer by number of doses produced and sold globally (more than 1.3 billion doses) which includes Polio vaccine as well as Diphtheria, Tetanus, Pertussis, Hib, BCG, r-Hepatitis B, Measles, Mumps and Rubella vaccines. It is estimated that about 65% of the children in the world receive at least one vaccine manufactured by Serum Institute.

Thermax has successfully commissioned 22 TPH biomass briquette fired boiler for their Hadapsar (Pune) vaccine plant. The main issues faced were the space constraint and the impact of the biomass fuel dust near the vaccine plant. This plant layout and boiler installation are customized to remove the space constraint which is the unique pentagon-shaped area. There was a tough competition for this project and Thermax process heating solutions bagged this opportunity with technology advancement and expertise in the field of biomass combustion.


Thermax has offered Combipac Reciprocating grate boiler ensuring 100% firing of biomass briquettes. Thermax has technology tie-up with Lambion GMBH who has over 100 years of experience in biomass firing solutions. Reciprocating grate offers progressive combustion with distinct combustion zones making it the ideal solution for biomass combustion with moisture up to 60%.

This grate offers huge fuel flexibility and can burn complex fuels like forest wastes, empty fruit bunches, spice waste, soya stock, and many other biomasses. Reciprocating utilizes successive oscillation of grate castings mounted on different trolleys for the continuous movement of fuel. These trolleys are driven by independent hydraulic cylinders and alternate movement of grate blocks pushes the fuel in the distinct combustion zones of the grate. This gives toppling action to the fuel a particle hence ensures complete combustion.

The advantages of reciprocating grate are:

  • 100% combustion
  • Highest uptime and efficiency
  • Very low emission


The steam generated from the boiler is used throughout the plant for an important process of sterilization and
clean steam generation for advanced procedures in the plant. On an average 2 lakh, the vaccine is manufactured
in a single lot and 12 lakh vaccine on an everyday basis through this process

This entire boiler plant is automatically operated with only 2-3 operators are needed for managing the entire operation. In the current world of dynamic pricing of the furnace, oil customer is benefited with an assured 30% cost savings by shifting to biomass briquettes. High-quality steam and assured uptime is the key for any successful operation of the pharma industry.

Thermax has once again demonstrated its capability as a reliable partner for customer’s success.
Cementing the long-term association of the two companies Thermax is proud to be a part of the biotechnology company’s work of saving the children with the vaccines that are manufactured at this plant while also saving the environment.


The Adaptation of an efficient boiler system from Thermax and the change in fuel from FO (furnace oil) to biomass briquettes helped serum institute to achieve these challenging results with just 3-4 people managing the complete plant operations

  • Fule cost saving up to 30 %
  • Space constraints resolved
  • Higher efficiency steam generation


A strategic business unit offers packaged boilers, thermal oil heaters, waste heat recovery boilers,hot water, and air generators. These are available in modular construction as a standard package configuration or a custom design for specific requirements. Innovated by a strong R&D that focuses on customer applications, we offer a range of heating systems designed to combust a wide range of solid, oil & gas fuels including biomass and heavy liquid fuels.



The shrinking profit margins and fierce competition coupled with increased taxes and higher logistics cost has compelled the cement manufacturers to reduce operating expenses and increase throughput without allocating considerable CAPEX.

This has led the Cement Manufacturers as well as Equipment Suppliers to look out for solutions which will yield maximum equipment efficiency enabling higher throughput of the existing plant. Thermax has acknowledged the market requirement and introduced a patented pulsing system that improves the bag filter performance in an innovative way. The success story of Thermax’s innovative solution to address the needs of the cement industry is presented below:


Myhome Cement, Hyderabad approached Thermax for a solution to upgrade its existing cement mill bag house to increase its mill feed capacity from 175TPH to 220TPH. However, increasing its capacity in as is condition was notpossible since the existing Induced Draft (will be referred to as ID henceforth) Fan of Cement Mill had flow & static pressure limitations due to higher pressure drop/ losses in system. The data in Table 1 presents the input parameters for existing operation and future enhancement:

Sr. No. Description Slag/Clinker Grinding Mill Bag Filter – Existing (Design Data) Slag/Clinker Grinding Mill Bag Filter – Enhanced (Design Data)
1. Cement Mill Bag filter Online Online
2. Quantity 1 1
3. Industry Cement Cement
4. Application Slag/Clinker Mill Filter Slag/Clinker Mill Filter
5. Mill Feed, TPH 175 220 (21% increase desired after Mill upgrade)
6. Volumetric flow 5,95,000 Am3/hr 7,00,000 Am3/hr (15% increase, desired)
7. Gas temperature continuous 90°C 90°C
8. Max Gas temperature Bags can Withstand 130°C 130°C
9. Bag Filter Design Pressure +/- 1500 mmwg +/- 1500 mmwg
10. Static pressure at Bag Filter inlet (max) (-)450mmwg (-)450mmwg
11. Dust to be handled Slag / Clinker Dust Slag / Clinker Dust
12. Dust properties Abrasive, Free Flowing Abrasive, Free Flowing
13. Dust concentration in the gas at Inlet of bag filter (slag only) 248 gms/m3 257 gms/m3 300 gms/m3(max)
14. Outlet Emission 30 mg/Nm3 30mg/Nm3
15. Bulk density of dust for Power 1,200 kg/m3 1,200 kg/m3
16. Particle Size Analysis 4,200 Blains 4,200 Blains
17. Moisture content in the gas Upto 8% Upto 8%
18. Moisture dew point of gas 59°C max 59°C max


Higher CAPEX
  • Generally, this kind of bag filter upgrade calls for an increase in the number of filter bags/ modules, to maintain air-to-cloth ratio (will be referred to as ACR henceforth) by increasing the fabric collection area and to maintain the Differential Pressure (will be referred to as DP
    henceforth) across the system
  • Any rework in an existing plant requires a lot of re-routing of existing facilities, in order to accommodate extra filter bags/modules. This results in increased expenditure for the customer
Space constraints

Space constraint was a challenge due to a compact plant layout and hence no space to accommodate additional bag filter modules.

Revenue loss due to downtime

Longer downtime required for addition of the bags/module resulting in loss of production and revenue accordingly



Thermax’s state-of-the-art Research, Technology and Innovation center (RTIC) has developed an innovative bag filter pulsing system which can effectively dislodge dust from bags at low pressures resulting in effective control of bag filter DP and ensure higher bag life. In fact, this also addresses the challenge of effective cleaning of long bags. The system generates low pressure pulses which travel right up to the bottom of the bag causing ripple effect on the bags and effectively dislodging dust, a panacea for cement
manufacturer’s plant operations woes.

The picture below represents the Computational Fluid Dynamics (CFD) pattern for Pulse Cleaning System; Type C is Thermax’s Intellectual Property (IP).


Sr. No. Parameters for 100% Slag Grinding Case 1 With Old Pulsing System Case 2 With Improved Pulsing System Case 3 With Improved Pulsing System
1. Mill Feed 175 – 180 175 – 180 185 – 190
2. Flow, m3/hr 5,65,000 – 5,80,000 5,65,000 – 5,80,000 7,05,000 – 7,15,000
3. Fan, RPM 800 – 810 800 – 810 980, Full RPM
4. Fan Power, KW 1,180 – 1,190 1,175 – 1,185 2,120 – 2,150
5. Pulsing Pressure, Bar 5 – 6 3.8 – 4.2 3.8 – 4.5
6. DP across Bag Filter, mmwg 90 – 100 70 – 80 115 – 120
7. Emission 30 mg/Nm3 30 mg/Nm3 30 mg/Nm3
8. Bag House Inlet/outlet Temp., °C 117 / 103 117 / 105 118 / 99

(*) Enhanced mill feed capacity of 220TPH was not achieved with old pulsing system due to very high DP across
bag house.

Thermax innovative pulsing system achieved 24% to 30% drop in pulsing pressure and 20% to 22% drop in DP
across bag filter (as in Case 2, Table 2)

The Mill Feed throughput was increased to 190 tph, but desired figure of 220 tph is yet to happen. However, the air flow in the bag filter was increased to 7,00,000 m3 /hr equivalent to 220 tph for couple of hours to observe the DP value under full load. The DP was around 115 – 120 mmwg while the original Bag Filter DP (design value) = 150 mmwg.

The above case clearly illustrates the benefits of the improved pulsing system i.e., reduced DP, reduced compressed air requirements, increased throughputs and higher bag life.

The set of benefits realised by customer (Myhome Cement) due to innovative pulsing system in an existing cement mill bag filter:

1. Savings in electric power consumption of ID fan:

Reduction of 20mmwg in dp across Bag Filter (Table 2, Case-1 & 2) would convert to 5KWH which would mean a yearly saving of 5KWH x 8,000 x Rs.5* per KWH = Rs. 2,00,000 (Rs.5 per KWH – Ave. India Industrial Unit Rate)

2.Savings in compressed air power consumption:

Reduction in pulse pressure from 5 – 6 kg/cm2 to 3.8 – 4.2 kg/cm2 , means a net reduction by 24% to 30% in air compressor operating expenses

3.Saving due to extended bag life:

Apart from other governing factors, compressed air pulse pressure and pulse frequency plays an important role in the life cycle of bag house. The innovation in the pulsing system technology by Thermax has controlled these vital parameters to safeguard the cement manufacturers from frequent purchase of bags translating into lower operating expenses

4.Saving due to pulsing system up gradation vis-à- vis additional module integration:

Conventional approach for DP reduction is reduction in ACR which would mean increase in module size. As against this, upgrading to new pulsing system would mean savings to the tune of 80 – 85% of capital cost. In addition, there is downtime reduction and intangible saving in terms of space.


Thermax was referred for studying the possibility to control higher DP across the bag house, during change in operation of bag house fan from 810-820 RPM (Results: Case 1) to higher speed of 960-980 RPM (Results: Case 3), for improving the mill throughput.
Instead of increasing the modules in the bag house, Thermax Team has modified pulsing system to reduce the DP in higher ID fan RPM operation. The modified pulsing system was installed and observed for the DP reduction from 85 – 95 mmwg to 65 – 75 mmwg and pulse air pressure reduced from 5 – 6 kg/cm2 to 3.8 – 4.2 kg/cm2.

“We appreciate Thermax for their support for solving the DP problem and overall savings in power cost in terms of DP reduction & Compressor Air Pressure reduction,” said Mr. Narang, MyHome Cement, Hyderabad.

Authored by

Mr. Arijit Dutta

Head of Innovation and Service Business Group

Thermax Limited | Air Pollution Control

Download Case Study

Raw Mill – Kiln Application in Cement Industry


M/s. Chettinad Cement Corporation Limited (CCCL), An Indian Rs 8.5 Billion business group is into Manufacturing (Cement, Silica, Quartz, Grits) & Services (Construction, Transports, Ship Management, Clearing & Forwarding), is one of the major cement manufacturers in Southern India with total cement production capacity of 3 MTPA having manufacturing units at Puliyur, Karur and Karikkali, Dindigul in Tamil Nadu.


The rotary kiln is the heart of a cement manufacturing plant. Cement kilns have all chemical ingredients. These
ingredients are at a broad range of gas temperatures from 100° to 1650°C.
The emissions contain:

  • High concentrations of alkaline solids, including sodium and potassium oxides;
  • High concentrations of freshly created Calcium Oxide
  • Volatiles; and
  • Organic gases

At CCCL, the kiln gases are at around 900 deg C. Pyroprocessing consists of five stages. Preheater exit gases are distributed based on requirement of Vertical Roller Mills for Raw Material Grinding and Vertical Roller Mill for Coal grinding. M/s CCCL has installed gas cooling system in the Preheater down-comer to bring the outlet gas temperature to about 310 deg C. In existing GCT, this temperature is further brought down to about 220 deg C and they are polished through the Air Pollution Control Equipment.


The Plant at Puliyur, Karur was operating at a capacity of 2,800 TPD clinker production. For the operation of the Raw Mill (Vertical Roller Mill), existing system was 2-fan circuit. The existing system consisted of Gas Conditioning Tower (GCT) followed by Electrostatic Precipitator (ESP) for the control of particulate emissions from the kiln and raw mill. Since the existing circuit was designed in early 90’s for lower capacity of Kiln, CCCL wanted to look at the various alternatives to reduce the emissions going out of the stack. CCCL decided after the initial scrutiny to award the work to m/s Thermax for suggesting various alternatives to meet the above objective. After much deliberation, Thermax and CCCL jointly decided that the best solution was to design a Bag House System in series with the existing ESP, (ESP – considered as a pre-collector). The system was guaranteed to give 25 mg/nm3 outlet emission with higher plant capacity.The system was converted from 2-fan circuit to 3- fan circuit. The major challenges handled by Thermax in designing the Bag House System in series with ESP were following:

  • Handling very fine dust at the inlet for Bag House coming out after ESP
  • Handling gases with higher moisture content coming out of the existing GCT.

Like in any cement plant, the Bag House operates in two basic modes of operation:

  1. Direct Mode Of Operation – All the Preheater exit gases shall be routed directly to bag house since the raw mill is not operating
  2. Compound Mode Of Operation – Here the Raw Mill is in running condition, therefore major part of Preheater exit gases will be routed through the Raw Mill circuit( including Raw mill , ESP and ESP fan) before going through the baghouse.


The Reverse Air Bag House (RABH) was installed after ESP to handle the exit gases from Preheater / RawMill. After conducting thorough analysis on world wide similar reference installations for the suitability of filter media for achieving lower emissions, filter media / bags made up of Fibre Glass woven fabric along with Poly Tetra Fluro Ethylene (PTFE) laminate was selected for this installation. The chosen woven glass fabric posses the following characteristics:

  • PTFE laminate is a micro porous membrane which collects even sub-micron sized particles
  • It has excellent dust cake release property
  • Due to its non-stick nature, it ensures low differential pressure across the fabric
  • Also, PTFE laminate is moisture resistant and protects the woven glass fabric from effects of moisture.
  • Mainly suitable for this application because of its inert nature, compatibility with the kiln gases and the
    temperature resistance.

Bags of more than 10 meter length were used for optimum floor space usage. As an operating principle of RABH, periodically the bags are cleaned using the recirculation of the cleaned air from the outlet of the RABH. The dust collected from the bag house is transported to Silo / preheater feeding elevator.
Having rich experience & expertise of more than 25 years in product line of ESP, Thermax recommended to charge only one out of three fields of this ESP which ensured the inlet dust load of bag house up to 50 mg/Am3 (from inlet dust load of 200 gm/Am3) and also maintained the outlet dust particle size from ESP in range of 10-15 microns which is good for the agglomeration. It was decided to conduct Computational Fluid Dynamics
to analyze before hand, the fluid mechanics of gases with higher moisture content. Numerical methods and algorithms were extensively deployed to arrive at the proper and uniform distribution. CFD was used for the components at the development stage itself to optimize the effectiveness of the component before actual installation The outputs of the analysis were presented as color plots of velocities (arrow / contour) and pressure (contour) at




Thermax was able to handle this complex issue of dust emission, through its extensive knowledge base of GCT, ESP and RABH technologies under one roof with requisite knowledge of the cement manufacturing process. As always, Thermax has once again delivered as per customer’s expectations in all respects and the emission levels are less than 25 mg/Nm3!!!!!

Iron Ore Pellatisation Application in Steel Industry – Grate Kiln Process


Vale S.A. is a Brazilian multinational diversified metals and mining corporation. In addition to being the second-largest mining company in the world, Vale is also the largest producer of iron ore pellets. Vale S.A opened a 9 MTPA (2 x 4.5) Iron ore pellatisation plant in Sohar, Sultanate of Oman., on March 3rd, 2011. High
grade iron ore for the plant is imported from Brazil & finished product is sold to Steel plants globally as a raw
material feed for Blast furnace or Electric arc furnace.


Pellatisation process turns fine –grained iron ore into hardened balls of approx. 8 to 16 mm diameter, which are used as feed in Blast Furnace, Electric arc furnace or DRI plant. Fine grained high quality Iron ore is mixed uniformly with Lime stone, Coke Breeze along with Bentonite & moistened with water & taken to a balling drum were in centrifugal force reduce the moistened raw material to ‘Green Pellets’ of required size as specified by customer. The Green pellet thus obtained is taken to an indurating furnace having heat resistant perforated cast iron traveling grate bars arranged on two rotating drum to make an end less belt.
Green Pellet is evenly placed at the feed end & burners are arranged opposite each other on longitudinal sides of the preheating & firing zone. As the belt progress a series of heavy duty fan draw air through the pellet bed & coke breeze in the Green pellet catches fire. The speed of the belt is arranged in such way that the pellets harden uniformly & emerge as red hot pellet at discharge end.
The dust laden gases are treated in Pollution control equipment before letting out through stack. Unlike in ‘Straight Grate’ process a ‘Grate Kiln’ process employ only one burner situated at the discharge end of the Rotary Kiln. Forced ‘Annular coolers’ are located at discharge end to uniformly cool pellet by an updraft of ambient air before transporting to storage silo.


Grate Kiln process is unique process designed to evenly indurate pellets to increase its mechanical properties. This process employ a conventional ‘Straight Grate’ followed by a ‘Rotary Kiln’ designed to churn the pellets & thus increase even heating as well to avoid fragmentation in transportation. As against a conventional burner the hot gases from the Rotary kiln are reused to preheat the green pellets so that the moisture in the Green pellet is gradually released & avoid steam formation inside pellet which would otherwise rupture the pellets.
Technology for the Project was offered by KOBELCO, Japan. who has recommended Grate Kiln Technology of Metso Minerals. ‘Grate Kiln’ process was then a ‘first- of- a-kind’ application for Thermax, despite having supplied numerous Air pollution control equipment on ‘Straight Grate’ Pellet plant. The challenge in this case was the high dust load generated due to churning of pellet inside the Kiln as well space constrain in Location of


Process engineers at Thermax carried out extensive study & based on performance data of ‘straight grate’
Pellatisation Process derived optimum design of ESP for ‘Grate Kiln’ Process & accommodated in the given
floor space without compromising on technical parameters .

The performance Guarantee test was done after commissioning of ESP & all ten units of ESP shown an emission of less than 50mg/Nm3

solution guide
Solution Guide
Customer Care
Call us
Customer Care
Call us
To Enquire

I Agree to the Thermax Terms of Use and Privacy Policy