1. ECS/ WHB solutions

ECS/ WHB solutions

The Evaporatie Cooling Systems and waste heat boilers are part of the iRecovery family for cooling the parts and recovering heat from hot streams.

The Evaporative Cooling System is part of the iRecovery fasmily. Pressurized water circulates with constant temperature at the boiling point. The parts are cooled through partial evaporation of water. The recirculation flow is lower than in a standard cooling system.

i Recovery® waste heat boilers are also the technology to recover energy of the waste gas from all other industrial furnaces and processes, i.e. aluminum smelters, rotary hearth furnaces, glass furnaces, plants for production of zinc, copper, nickel etc.

Waste heat boilers can also be used to collect the energy from different smaller furnaces, i.e. forging furnaces; where one forging furnace is not worth starting a heat recovery project a hall full of forging furnaces has a lot of potential when the off gases get collected.

Tenova is specialized on off gas with difficult conditions like high dust load, aggressive dust combination and intense post combustion; especially due to high CO content.

The right design for these conditions together with advanced boiler cleaning technologies guarantee safe and reliable operation for many years.

  • Efficiency

    Efficiency

    • Reduced overall energy consumption, reduced carbon footprint
    • Improve the effectiveness of the off-gas cooling process
    • Usage of steam for Drives, Secondary Metallurgy, District Heating
    • The system is able to work in a complete automatic way. Continuous supervision and monitoring by dedicated personnel is not mandatory
    • Transformation into electric energy = Power generation
  • Environment

    Environment

    • Environmental friendly solution
    • Separation and extraction of heavy particles / pieces of light scrap, slag
    • Dust remains always like powder
    • Reduced carbon footprint. Several countries are giving also special funds for green technology which can significantly help to reduce the pay-back time
    • Reduction of furanes and dioxines formation
  • Reference

    Reference

    • First EAF reference, 7 EAF installations worldwide
    • Overall references: 52

Downloads

References

  • Customer
    Project name
    ECS Type EAF Furnace
    GMH Georgsmarienhütte GmbH
    Germany
    2009

    Evaporative cooling system of the waste gas duct for an electric arc furnace with steam transfer to the in-house steamork network. Plant type: electric arc furnace 140 t/h with cooled waste gas duct.

    GMH has a DC electric arc furnace producing exhaust gas temperatures of up to 1800 °C. The exhaust gas contains combustible parts which burn in the waste gas duct as well as liquid slag and steel. The Tenova system, including the first element of the waste gas duct, was completely designed as evaporative cooling system.

    Extremely high exhaust gas temperatures in the first two elements of the waste gas duct and the tilting construction of the first element, which can be moved to the side while the furnace is loaded. Despite the typical variations of a charge furnace the steam generation should be as continuous as possible. This is achieved using intermediary steam storage.

    A generous spatial separation of furnace and cooling system considerably simplifies maintenance works during ongoing production. A quick automatic pressure relief of the isolated first two elements in the event of damage considerably increases the general plant safety. The switch of the cooling system was carried out during a very short scheduled maintenance downtime.

    Project Figures

    20t/h
    13-20,5 bar saturated steam
    approx. 3.2 million €/year
  • Customer
    Project name
    ECS Type EAF Furnace
    TPCO
    China
    2016

    Furnace type: 130 t/h EAF. ECS Duct and Waste Heat Boiler applied on an EAF for steam generation in a contracting model. The goal of the application of the iRecovery® system at TPCO is the reduction of primary energy consumption. TPCO is able to replace the entire steam required for one of their VD plants by steam generated by the iRecovery® system. Since even more steam is generated, the remaining steam is fed into the steam grid which is connected to other consumers as plant heating, etc.

    TPCO (Tianjin Pipe Group Corporation), Tianjin works, operates three Electric Arc Furnaces. For several applications, e.g. VD plant, a steam network is installed on their premises. In order to reduce primary energy consumption for steam generation TPCO decided to generate steam by waste heat recovery of the hot off gases evolving from EAF#2.

    To EAF#2 not only scrap is charged but also hot metal (up to 90 %). This leads to very high temperatures (and therefore a big difference between average and peak conditions) and to high dust loads in the off gas. The entire design has taken the difficult conditions into consideration. The off-gases are passed through an ECS (evaporative cooling system) duct towards the waste heat boiler. The waste heat boiler is designed as corner tube boiler and therefore state of the art equipment.

    The self-supporting structure of this design reduces steel structure and therefore weight and costs. The steam drum, which is connected to the ECS duct and the evaporatorsinside the boiler, is fully integrated into to the corner tube boiler. In addition economizer bundles are installed at the tail of the boiler in order to heat up fresh feed water. Tenova supplied all core components of the heat recovery system. Auxiliary equipment was supplied by the energy contractor and purchased on the Chinese marked to reduce investment costs.

    Project Figures

    33 t/h
    13 – 27,5 bar
    82m

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