Heat ExtractionCondensed information:
Boilers are heat transfer machines whose regulation is usually controlled
by integral parameters (flue gas temperature, steam volume, residual oxygen
Generally, the process of heat transfer (from chemical energy into thermal energy) cannot be observed directly, due to the closed design of boilers. The quantity of heat released by heat transfer surfaces is not recorded as a standard value.
As a result of the secondary influences (e.g. pollution, corrosion) if fuels it might be advantageous to record the “heat exposure” of individual components, thus influencing the distribution of heat for several components to the effect that their heat exposure remains constant - and therefore is less corrosive.
From the view of process engineering there are various approaches of recording heat exposure per component or per area, in the course of optimising certain process features.
Regarding power plants, the relevant points are:
- Giving support by controlling the flame zone
- Recording flue gas imbalances
- Recording the degree of fouling
- Recording remaining wall thickness
- Recording first symptoms of a functional deficit (e.g. overheating)
- Control of protective layer functionality
- Control of exposure of heat transfer surfaces (reducing corrosion)
CheMin’s patented sensor system measures temperature patterns on that side
of the tube/component which is not exposed to the hot gas and therefore not subject
to the high corrosion risk on the flue-gas side.
Due to the sensors’ high accuracy of about 0.0x Kelvin, a wide variety of applications is possible.
These applications come into question for boilers as well as all “machines” with
- a metal encasement and
- an interior heat source and/or
- irregular temperature patterns in the interior.
Possible applications also include solar towers, heat transport in pipes, temperature
stratifications in containers, the absorption and release of heat in heat
CheMin: The “Heat Detectives”
(temperature patterns and heat flux made visible)