Abstract
The combustion dynamics of coal, wood chips and their mixture is
investigated. Load change capability and the effect of the individual control
variables, for example the mixture ratio of different fuels, on pilot-scale
CFB boiler dynamics were also studied. Disturbances in fuel feeding cause
fluctuations in the flue gas concentrations. Changes in the heating value are
possible due to varying moisture content of the fuel. Both these disturbances
affect the instantaneous firing rate in a boiler. Also the characteristics of
the fuels have to be taken into consideration when designing boiler control
systems. When co-firing two fuels with clearly distinct combustion
characteristics, direct assumptions based on each fuel’s characteristics
cannot be made about combustion behaviour of their mixture. Combustion
experiments with coal and wood chips and their co-firing were carried out in a
pilot-scale CFB reactor (VTT) and a large-scale CFB boiler (Chalmers). A
comparison of the combustion in the two different size reactors, provides
information about scaling. The combustion responses due to changes in the fuel
feeding of the two circulating fluidized beds are analyzed by a dynamic
model.
| Original language | English |
|---|---|
| Pages (from-to) | 2043-2051 |
| Journal | Fuel |
| Volume | 86 |
| Issue number | 14 |
| DOIs | |
| Publication status | Published - 2007 |
| MoE publication type | A4 Article in a conference publication |
| Event | 6th European Conference on Coal Research and its Applications - University of Kent, Canterbury, United Kingdom Duration: 5 Sept 2006 → 7 Sept 2006 |
Keywords
- CFBC
- Dynamics
- Fuel mixtures