ATS AIR TREATMENT SYSTEM SRL
Via Gioberti, 3
20090 Trezzano S/N (MI) - Italy
VAT 10041500157

  • T. +39 02 48400626
  • F. +39 02 48400674
  • E. info@atsecologia.it

ATS just completed the installation works for the CO reduction into the Torino Nord HRSG unit

The cogeneration plants of Iren Energia connected to urban district heating system produces heat delivered to 550,000 Turin inhabitants and make Turin the the biggest city district heating in Italy and one of the most effective in Europe, with significant environmental benefits compared to traditional heating units.

Iren Energia integrated system for cogeneration of heat and power has also some spare units (BIT, Mirafiori Nord, Moncalieri, Politecnico and Torino Nord), as backup of the Moncalieri and Torino Nord power plants.

 

External picture of IREN cogeneration plant in Torino Nord


Torino Nord cogeneration plant produces electrical power and heat for the district heaying. Most significative parts of this unit are:

• the combined cycle thermoelectrical unit (gas and steam turbines), dual shaft, in cogeneration, with a gross power of about 400 MW, fed just with natural gas;
• the 3 steam generators for the integration of power and backup, with an overall thermal power of 340 MW, fed with natural gas;
• the heat accumulation system, composed by 6 tanks with a global capacity of 5.000 cubic meters.

 

The turbine, with an electrical power of 270 MW, is a single shaft device with an air compression section done in 15 stages (compression rate 18 bar) coupled with a turbine section in 4 stages. The gradient of normal loading/unloading is 13 MW/min. Turbine blades, subjected to stress, are cooled internally by the use of air and are protected also externally by a film of cooling air injected through hole done into the blades. Blades for conveying air into the compressor are tilt adjustable. The turbine is provided by a recovery system for “clearances, blades, casing/rotor” hydraulically actuated that allows an increase of general performances.

The Heat Recovery Steam Generator (HRSG) is horizontal type, with three pressure levels and superheater. Its main components are:

 

 

IREN Heat Recovery Steam Generator (HRSG) scheme for Torino Nord cogeneration plant

 

• Thermal exchange sections in High Pressure (HP), medium pressure (MP), low pressure (LP), and final heat recuperator;
• Drums in HP, MP and LP with hydrometric columns and accessories;
• 60 metres high stack;
• Degaser;
• Annular combustion chamber with 24 low NOx burners and combustion section that surround the inlet of the first stage of the turbine;
• Catalytic system for the reduction of nitrogen oxides (NOx) that strongly reduce the concentration of such pollutants to the stack emissions; 
• Catalytic system for the oxidation of carbon monoxide.

This last item, in particular, has recently been the subject of a tender that Iren Energia assigned to ATS, in collaboration with Torricelli SpA.

ATS was in charge of the design and installation of the system for the reduction of carbon monoxide in order to obtain a lowering > 98% to meet the strictest Italian regulations also during start-up and shut-down phases. In details, during such project, our activities referred to:

• Sizing and design of the catalytic system;
• Design and realization of the catalyst supporting structure;
• Erection of the catalytic system inside the HRSG;
• Preparation of commissioning and test procedures.