Energy materials and fuels
Fuel, sorbent, catalyst
and residue behavior across solid fuel and thermal energy processes
Coal, lignite, coke, biomass, pellets, recovered fuels, sorbents, catalysts and ash are not one category
Particle size, moisture, cohesion, bulk density, grindability, pellet durability, porosity, reactivity, fuel chemistry and ash composition decide whether a material discharges, mills to the right fineness, feeds a burner steadily, resists self-heating in the pile, converts cleanly and leaves a residue you can reuse. This page connects what you are seeing on the plant to the mechanism behind it and the measurement that settles it.
Find your route
Start with the material, then the behavior
Energy materials and fuels do not behave as one category. Pick the coal, lignite, coke, biomass, pellet, torrefied fuel, recovered fuel, blend, sorbent, catalyst, ash or char class, then the behavior you are seeing in the process. The result names the mechanisms worth separating, the measurement to start with, and where in the process it usually shows up. It is a triage route, not a diagnosis.
- 1Material
- 2Behavior
- 3Route
Step 1 Â What are you handling?
Step 2 Â What are you seeing?
Step 3 Â Your route
Material routes
Coal, biomass, recovered fuels, sorbents, catalysts, chars and residues
Energy and fuel processes handle fine coal powders, moist lignite, hard petroleum coke, fibrous biomass, densified pellets, brittle torrefied materials, heterogeneous recovered fuels, co-firing blends, reactive sorbents, porous catalysts, ash and recovered carbon products with very different particle sizes, densities, moisture sensitivities, mechanical strengths, chemistries and thermal behaviors. Each class has its own behavior profile, so the most useful route starts with the material before moving to the visible process problem.
Pulverized coal and solid fossil fuels
Fine coal powders vary in moisture, ash, rank, and grindability. Cohesion, dust, segregation, and combustion reactivity affect milling, feeding, conveying, and burner stability.
Lignite and low-rank solid fuels
Low-rank fuels retain more moisture and can cake, smear, or self-heat. Drying history, particle strength, oxidation, and storage conditions affect flow and safe handling.
Petroleum coke and carbonaceous fuels
Petroleum coke and related carbon fuels can be dense, abrasive, and difficult to ignite. Size, hardness, fines, sulfur, and moisture affect milling and combustion.
Biomass powders and milled feedstocks
Milled wood and agricultural biomass are fibrous, elastic, and low in bulk density. Moisture, particle shape, bridging, and dust affect feeding and thermal conversion.
Wood pellets and densified biomass
Pellets and briquettes must retain strength through storage, transfer, and dosing. Moisture, density, fines generation, and durability directly affect flow and conversion consistency.
Torrefied biomass and biochar
Thermally treated biomass is brittle, porous, and often highly hydrophobic. Particle size, dust, attrition, oxidation, and pore structure affect handling, storage, and reactivity.
Refuse-derived and recovered fuels
Recovered fuels contain mixed plastics, paper, textiles, wood, and mineral fragments. Composition, particle size, contaminants, density, and segregation affect feeding and combustion.
Fuel blends and co-firing mixtures
Blends combine materials with different sizes, densities, moisture levels, and reactivities. Segregation, uneven dosing, and variable burn behavior can reduce process stability.
Combustion sorbents and emission-control powders
Limestone, dolomite, hydrated lime, and sorbent powders must disperse and react quickly. Fineness, moisture, purity, and injection behavior affect pollutant capture.
Gasification and reforming catalysts
Catalyst powders, pellets, and supports require controlled size, porosity, strength, and surface condition. Attrition, poisoning, fouling, and thermal cycling affect activity and life.
Boiler ash and combustion residues
Fly ash, bottom ash, slag, and unburned carbon vary in fineness and chemistry. Moisture, agglomeration, leachability, and carbon content affect handling and reuse.
Pyrolysis char and recovered carbon
Chars and carbon products vary in porosity, ash, volatiles, and particle size. Classification, deagglomeration, contamination control, and activation affect consistency and value.
Quick comparison
Material route, common risk, first measurement
The same symptom points to different mechanisms depending on the material class, particle size, moisture, density, mechanical strength, chemistry, reactivity, thermal history and process step. This is the fast bridge between energy material and fuel behavior and the most useful first measurement route. The rows follow the same order as the cards above.
Energy material and fuel routes, the handling or processing risk each one carries most often, and the measurement worth running first.
| Material route | Common handling or processing risk | Useful first measurement |
|---|---|---|
| Pulverized coal and solid fossil fuels | Dusting, caking, segregation, feeder variation, unstable ignition, and inconsistent burnout | Particle size, moisture, flowability, bulk density, and proximate analysis |
| Lignite and low-rank solid fuels | High moisture, smearing, caking, self-heating, drying variation, and poor storage stability | Moisture, self-heating tendency, caking, flowability, and thermal behavior |
| Petroleum coke and carbonaceous fuels | Abrasion, dusting, milling variation, feeder wear, segregation, and inconsistent conversion | Particle size, hardness, moisture, grindability, bulk density, and volatile content |
| Biomass powders and milled feedstocks | Bridging, low density, moisture uptake, dusting, segregation, and feeding instability | Particle size, moisture, bulk density, flowability, particle shape, and compressibility |
| Wood pellets and densified biomass | Breakage, fines generation, moisture uptake, caking, density variation, and poor feeding | Pellet durability, moisture, bulk density, crushing strength, and fines content |
| Torrefied biomass and biochar | Attrition, oxidation, dusting, segregation, self-heating, and variable reactivity | Particle size, moisture, surface area, volatile content, dustiness, and thermal behavior |
| Refuse-derived and recovered fuels | Heterogeneity, oversize, contaminants, bridging, segregation, and unstable feeding | Composition, particle size, moisture, bulk density, calorific value, and contaminant content |
| Fuel blends and co-firing mixtures | Segregation, moisture migration, density mismatch, feeder bias, and unstable conversion | Blend uniformity, particle size, bulk density, moisture, and segregation tendency |
| Combustion sorbents and emission-control powders | Caking, poor dispersion, feeding variation, incomplete reaction, and excessive consumption | Particle size, moisture, reactivity, surface area, flowability, and composition |
| Gasification and reforming catalysts | Attrition, fouling, poisoning, pressure drop, activity loss, and thermal degradation | Particle size, surface area, pore structure, strength, composition, and activity |
| Boiler ash and combustion residues | Dusting, caking, variable carbon content, leaching, poor flow, and inconsistent recovery quality | Particle size, moisture, carbon content, composition, leachability, and flowability |
| Pyrolysis char and recovered carbon products | Variable ash, moisture, volatiles, contamination, agglomeration, and inconsistent reuse quality | Particle size, surface area, ash, moisture, volatile content, and purity |
One risk per row is the one most often reported, not the only one that occurs. Use the selector above to work a specific combination through to a route.
Recurring problems
Start from the behavior you can see
These eight come from your own route card and continue block: flow, caking, dust, fuel-feed variation, segregation, pellet breakage, moisture sensitivity and self-heating. Each is one idea rather than three, so the card and the mechanism list line up. Combustion instability is an outcome rather than a powder behavior, so this page routes to it through the material and measurement sections instead of a card of its own.
Also covered: contamination and fouling, agglomeration, blend inconsistency, electrostatics. All symptoms
Measurement routes
The test that answers your question
Energy material and fuel behavior rarely resolves to one number. Particle size, morphology, moisture, self-heating tendency, cohesion, bulk density, grindability, pellet durability, dustiness, porosity, fuel chemistry, calorific value, ash composition and blend uniformity can all contribute to the same visible process symptom. Pick the method by the question, not by the symptom.
Compare every method All test methods on the site, grouped by the question they answer.
Process routes
Where the behavior actually shows up
The same fuel, sorbent, catalyst or residue behaves differently depending on where it sits in the process. Receipt, drying, milling, storage, feeding, blending, densification, conversion, sorbent injection, conveying and residue recovery each expose a different property, a different safety concern and a different failure mode.
Go deeper
Guides and articles for energy materials and fuels
Longer reads that work through the mechanisms behind these routes, from the visible handling problem to material properties, measurement choice and interpretation.
FAQ
Energy material and fuel questions
Need the measurement, not just the guidance? PowderTechnology.info works closely with Delft Solids Solutions,
a contract research organization specializing in the physical behavior of powders and granules. DSS provides
contract testing and characterization, with its laboratory working in accordance with ISO 17025.
Contact Delft Solids Solutions.
