Investigation of ash deposit formation during co-firing of coal with sewage sludge, saw-dust and refuse derived fuel

Ash Deposition in Biomass Combustion or Co-Firing for Power/Heat Generation

“…Research efforts have been put into attempting to understand the mechanisms involved in the formation [15,44,48,55,56], slagging/fouling [52] and corrosion [35] of the ash deposits during biomass combustion or co-firing. During combustion processes, ash is formed from the fuel-bound inorganic materials through a combination of complex chemical and physical processes.…”

“…For example, the co-firing ratio of biomass in most PFC boilers is no more than 10%-15% on a thermal input basis due to the issues of increased ash deposition or accelerated corrosion rates for the boiler components. On the other hand, for grate boilers that have been traditionally used for solid fuel combustion on a relatively small-to-medium scale (15 kW up to 150 MW), co-firing of recycled fuels, packaging derived fuels, refuse derived fuels, recovered fuels and plastics with wood fuels or other by-products of forest industry was successfully demonstrated [56]. Co-firing of recycled fuels in small power plants is relatively less challenging as the steam temperature is usually lower than 400 °C and there is no risk of high-temperature corrosion.…”

Co-Combustion of Low-Rank Coal with Woody Biomass and Miscanthus: An Experimental Study

“…Concering the type of testing procedure used, it should be noted that such lab-scale tests are not yet considered standard testing procedure, although many laboratories worldwide do use them, including TU Clausthal [10], IVD Stuttgart [16] and the University of Newcastle [17]. This type of testing procedure is accompanied by standard ancillary techniques for sample preparation, see e.g., [10], or standard chemical techniques that provide useful information, e.g., AFT or Oxide determination.…”

“…This type of testing procedure is accompanied by standard ancillary techniques for sample preparation, see e.g., [10], or standard chemical techniques that provide useful information, e.g., AFT or Oxide determination. These chemical techniques are, however, imperfect slagging or fouling predictors, and testing by experimental facility is advisable, as it provides a more reliable evaluation of the slagging/fouling propensity of the given fuels [17].…”

Analysis of bed agglomeration during gasification of wheat straw in a bubbling fluidised bed gasifier using mullite as bed material

“…It was developed for fossil fuels with low phosphorous quantities and in its original form does not take account of the increased fouling tendencies associated with phosphorous in the form of P 2 O 5 . As the P 2 O 5 content of biomass fuels is relatively high the calculation has been modified as follows to take P 2 O 5 into account Kupka et al [14]:…”