Heat Recovery Steam Generators

Heat Recovery Steam Generators are used to recover waste heat from exhaust of gas turbines, boosting efficiency from 35% to 40 % range in simple cycle (also known as open cycle) mode to 55% to 60% range in combined cycle mode. The steam generated by HRSG can be used for process heating or generating electricity in a steam turbine. Such units are installed on gas turbines ranging from below 1MW upto 320MW.

These units are offered with features such as horizontal/vertical design, Natural/Forced circulation, triple pressure levels with reheat option, supplementary and fresh air firing mode with automatic changeover, bidrum/single drum.

Thermax HRSGs* incorporate the latest advances in thermal technology, offering benefits such as multiple pressure levels and unprecedented reliability. The growing number of Thermax HRSGs bears testimony to their importance in ‘clean energy' solutions.

Product Features

  • Single drum construction for reduced thermal stress during start-up & shutdown; special drum internals that promote circulation &  ensure high steam purity
  • Fully welded construction for quicker start-ups & shutdowns with welds safely located outside the gas path for higher reliability and longer life
  • Gas-tight, internally insulated ducting & casing for lower thermal loads; internal duct designed carefully for predictable performance & longer life
  • Tolerant to economiser steaming for better off-design operation; fully drainable super heater for higher reliability
  • Strategic soot blowing for oil firing
  • Firing gas, #2 and #6 oil in the duct burner
Boiler-Turbine-Generator (BTG) packages can be offered on a case-to-case basis.

Operating Range

  • Capacities: Gas Turbine size of 320 MW
  • Pressure: Up to 175 kg/cm2 (g)
  • Temperature: Up to 603ºC
  • Fuels: Natural gas/naphtha/HSD/kerosene/refinery gas, heavy high sulphur fuel etc.

Level of Prefabrication

Heat Recovery Steam Generators can have a very large size depending on the design of the unit and is there by offered as a fully modularized unit or a combination of modular and site assembled units.
  • Modularized - Modules prefabricated and hydrotested in workshop, made by pressure parts section and casing internally insulated to be transported to site.
  • Site Assembled - Workshop prefabricated harps to be modularized at the job site.

Major Clients


  • Aban Power
  • Internusa A/c Bekasi Power, Indonesia
  • Essar Power for Vadinar Power Co. Ltd
  • Abener for Hassi R'mel Project, Algeria
  • Lanco Infratech Ltd
  • Beta Infratech Pvt Ltd


  • Daelim for Numaligarh Refinery
  • ONGC Mangalore Petrochemical Ltd.
  • BPCL, Kochi

Chem and Petrochemical

  • Reliance Industries


  • OEP for Oswal Chemical & Fertilizer
  • Essar A/c Matix Fertilizer
  • Samsung A/c Banyu Urip
* The product is supported under a technical collaboration agreement with Babcock and Wilcox, USA.