Flue gas cooling – energy recovery

The ROTARY KILN INCINERATOR process produces hot flue gasses, suitable for energy recovery, depending upon client requirements.

Options and features:

  • Smaller systems typically use water injection to reduce flue gas temperature, prior to final flue gas emission reduction. The most cost effective solution, although without energy recovery.
  • Alternatively the flue gas can be mixed with ambient air to reduce flue gas temperature, a simple and reliable method for incinerators with a small thermal input.
  • Energy recovery is a viable option for incinerators with a higher thermal input, starting from 3 MW, depending upon the balance between investment costs versus returns. A wide range of options is available:

Energy recovery by the production of hot ambient air

Hot air can be used for:

  • Production of chilled water via an absorption cooling machine, typical application: medical waste storage room cooling.
  • Combustion air preheating to support other combustion processes.
  • Drying processes using hot air.
  • Steam generation or hot water production.

Energy recovery by the production of steam

Steam can be used for:

  • General energy supply as utility steam for other production processes.
  • Electricity generation using a steam turbine (up to approx. 1.5 MW electrical output for the product range of Dutch Incinerators).

Energy recovery based on thermal oil

Thermal oil can be used for:

  • Direct high temperature heating of other production processes.
  • Steam or hot water generation in case of an excess of energy.
  • Chilled water production.

Energy recovery based on the Organic Rankine Cycle (ORC)

ORC enables energy recovery and electrical power generation there where steam based energy recovery is not practically feasible, specifically for energy recovery at lower flue gas temperatures and smaller thermal input capacities.