Which factors influence the solid fuels inorganic composition?

The composition of ash forming matter in the biomass fuels is largely varying and depends on multiple factors, not only the biomass type. For example, for biomass, poor-in-nutrients soils can reduce the plant’s capacity to uptake inorganic substances. It was demonstrated that, in spruce, tree branches and twigs contain a higher content of inorganic matter (especially K, Na, Si) than stem wood. It is also known that delayed harvest in spring can result in a reduced inorganic content (especially K).

In this overview, a summary of twelve factors which can influence the biomass fuels inorganic composition is proposed.

Biomass type

1.     The plant species, e.g. variety, genotype.

2.     The state of the plant development or age, the plant growth cycles/season.

3.     The part of the plant considered (and mixes) such as leaves, bark, stem, fibres, tops.

Soil, climate and agricultural practises

4.     The soil characteristics: type, pH, nutrients or composition, pollutants, water quality.

5.     The type of fertilization or pesticides applied.

6.     The climate of the location: rains, atmospheric pollutants and external environmental factors (E.g. road side vegetation contaminated with salt (road de-icing); biomass from river maintenance; driftwood.)

Harvesting, transport, pre-treatment

7.     The selected harvest date and season.

8.     The collection method, harvesting operations (soil and dust incorporation, machines pollution, biological contamination) and transport conditions (ships, trucks potential contaminations).

9.     The storage type/time, if any, and the drying (or other pre-treatment/upgrading) type/duration, if any.

10.  The size reduction e.g. the fineness of the fuel or particles size distribution.

Analyses of the samples

11.  The material sampling method and its representativeness (sampling standards).

12.  The ashing method and the ashing temperatures (production of the ash sample to analyse) as well as the analytical instrumentation used for the ash composition analyses (errors theory).

These factors can influence the inorganic matter content of each biomass, that is why each fuel is different.

It might be complex for producers to control those factors, especially for low-grade or opportunity fuels. Detailed compositional data for the specific fuel to be processed are needed and it is not recommended to consider literature data.

In our thermochemical simulations, we study the ash behaviour of the specific fuel sample, mixture or portfolio, processed in each specific energy plant.

Expected large scale biomass projects in Europe and Asia

Expected biomass projects in Europe 2020-2021 (total > 6 million ton/year)

Company Plant Capacity (MW) Co-firing? Status Consumption
EPH Lynemouth 396 Dedicated 100% Commissioning Ranged 57-85% weekly availability
Q1 2020
1.6mn t/yr
MGT Teeside 299 Dedicated 100% Planned 31 July 2020 1-1.2mn t/yr
RWE Amer 630 80% by 2020 38% in Q3 2019 1.7-1.8mn t/yr
RWE Eemshaven A & B 777 15% “Almost at 15%” in
November 2019
800,000-830,000 t/yr
Uniper MPP3 1.1GW 15% November 2019 start 200,000-250,000 t/yr
Onyx Power Rotterdam 731 10% Offline until April 2020 500,000-550,000 t/yr

Expected biomass projects in South Korea during 2020-2022 (total > 4 million ton/year of pellets and chips)

Company Plant Capacity (MW) Start-up Wood pellet (t/yr) Wood chip (t/yr)
Korea South East Power (Koen) Yeongdong unit 2 200 June 2020 900.000
CGN Daesan Power CGN Daesan Power 109 December 2020 500.000
GS EPS Dangjin unit 2 105 December 2020 300.000 200.000
SMG Energy SMG biomass power
100 delayed to June-July 2021 430.000
Gwangyang Green Energy Gwangyang biomass
power plant
220 July 2022 (delayed) 480.000 528.000
Korea Midland Power Gunsan Bio 200 December 2022 (delayed) 800.000

Source: Biomass markets adjust to challenging times. Steady growth in demand.
Webinar – 19 March 2020. Public Argusmedia.com Market report

BIOFACT Ash Chart: ash content for 500+ biomass fuels

The BIOFACT Ash Chart is a high quality synthetic plot of the amounts of the inorganic fraction for 500+ solid biomass fuels. The fuels are belonging to different classes (20+) such as stem woods, barks, straws and grasses, shells and husks, fruits and residues, animal and industrial wastes. Median values for fossil fuels are included for comparison. It is useful to expand your overview on the renewable fuels portfolio.

Request us a high quality PDF suitable for A1 printing, email at defusco.biofact@gmail.com.

Expand the 2020 fuel inventory to available non-conventional biomass fuels

EU USA South America Africa South East Asia China and India
Wheat stalk Juliaflora Sugar cane bagasse (Brazil, Mexico) Elephant grass Rubber wood Sugar cane bagasse
  Soya stalk Juliaflora Juliaflora Sugar cane bagasse (Thailand) Mustard stalk
  Groundnut shell Coffee husk Coffee husk Eucalyptus (Australia, New Guinea, Indonesia) Coconut shell
  Cotton stalk Soya stalk (Brazil, Argentina) Rubber wood Rice husk Soya stalk
  Wheat stalk Acacia wood Acacia wood Coffee husk Groundnut shell
  Mesquite wood Invader bush Coconut shell (Indonesia, Philippines) Cotton stalk
  Shea tree Acacia (Australia) Wheat stalk
  Bamboo (Bangladesh, Indonesia, Thailand) Bamboo

Fuel analyses (available for same samples, upon request) can be used to produce sample specific BIOFACT Fuel Dashboards and simulation Reports of slagging, fouling and corrosion in combustion boilers.

The previous table integrates the IEA Clean Coal Centre summary related to low grade fuels.

Contact us for additional information related to the ash related risks of different fuels for new of existing boilers.