Carbolite CAF G5: a new generation of ash fusibility furnaces

When coal is combusted in the furnace of a power plant a powder-shaped residue or a glassy slag (clinker) forms and must be removed. Large coal furnaces suffer from clinker build-up and therefore expensive maintenance due to closure for removal of clinker. If the fusibility characteristics are known, control of temperature can avoid clinker formation.

Ash fusibility testing is designed to simulate as closely as possible the behaviour of coal ash when heated in either a reducing or an oxidising atmosphere, giving data indicating temperatures for sintering, melt and flow.

The new Carbolite CAF G5 ash fusibility furnace has been designed to test ash fusibility and optionally the increasingly popular determination of biomass or solid recovered fuels testing.


Carbolite CAF G5 ash fusion test furnace


The CAF G5 comes with a new software package offering the choice of automatic or manual analysis of samples. For manual analysis a grid overlay feature ensures accurate comparisons of the height and width of each sample.

The CAF G5’s automatic and continuous recording of digital images and increased camera resolution along with a zoom facility provide excellent quality test results. The large diameter work tube ensures that only one furnace is required to test more than six test pieces at any one time and fast heat up and cool down rates allow up to three tests per day to be completed.

An optional work tube integrated lighting system is also available when testing low ‘initial deformation’ temperature of SRF or biomass samples. The CAF G5 is designed to conform to relevant ISO, ASTM, DD and PD Standards


Key changes from previous models – all new features below are standard on the CAF G5

  • Automatic Analysis Software offering the choice of automatic or manual analysis of samples.
  • Software zoom function with improved resolution for post-test analysis of individual samples.
  • Temperature controller program set up within the software
  • One configurable grid assigned to each test piece
  • Space saving embedded computer with Windows 7 Embedded Professional software which runs future proof firmware.
  • Default software settings and individual analysis form for coal ash, biomass and SRF
  • Optional work tube integrated lighting system when testing low ‘initial deformation’ temperature of biomass or SRF samples

Other standard features of the ash fusibility furnace CAF G5 include:

  • Maximum operating temperature 1600°C.
  • Lightweight insulation allowing quick cooling permitting multiple tests to be completed in one day
  • Automated digital image capture of samples. The frequency of images recorded is set by the customer preference from every 1°C increment to every 20°C
  • Standard accessories including:
    • Sample carrier x 1
    • Sample tiles x 100
    • Sample loading tool x 1
    • Test piece mould x 1 (coal ash)
    • Test piece mould and hand press x 1 (biomass & SRF)
    • External mounting proprietary CO alarm x 1

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