Solids, coal and biomass

Some simulators ask you to pick a stream class before a solid can enter a flowsheet: a declaration of which parts every stream carries — fluids only, fluids with conventional solids, fluids with nonconventional solids, or all three. A paper that burns or gasifies coal usually chooses the class with all three.

LensaSim has no stream classes, because every stream already carries all three:

• The fluid phases — gases and liquids, which flash and take part in vapour-liquid equilibrium through the property method you chose.
• Conventional solids — minerals, salts, metals and the rest of the solids databank, with a heat capacity and a formation enthalpy of their own and a particle size distribution.
• Nonconventional components — coal, char, biomass, bio-oil, ash and polymers, defined from an analysis rather than a molecule.

A stream with no solids simply has an empty solids part. So the setup a coal paper describes needs no equivalent here: define the coal, feed it, and connect it to the blocks that use it.

1. Open Properties and expand Define a nonconventional component.
2. Choose the kind Coal / char. Start from Bituminous coal, Lignite or Biochar, or type your own analyses.
3. Enter the ultimate analysis (C, H, O, N, S, ash) and the proximate analysis (fixed carbon, volatile matter, ash), dry or as received — say which.
4. If you have it, tick Split the sulfur and enter the sulfur forms: pyritic, sulfate and organic. They must add up to the ultimate analysis's sulfur.
5. Enter the heating value as the laboratory reported it — gross or net, dry or as received — or leave it blank and choose a correlation.
6. Enter the moisture. The component is always the dry coal; the moisture is fed beside it as real water, so it evaporates in a dryer and appears in the flue gas.
7. Add to flowsheet. The coal's ash is added with it, as its own component.

• Ultimate analysis — the elements a combustor or gasifier turns into products, and, with the heating value, the coal's formation enthalpy.
• Proximate analysis — how the coal is graded, and a check on the ash: the two analyses must agree about how much of the coal is mineral.
• Sulfur forms — where the sulfur goes. Pyritic and organic sulfur burn to SO₂; sulfate sulfur is already oxidised and leaves with the ash. The pyrite also makes the coal denser.

• Heating value — the measured value, or a correlation from the ultimate analysis: Channiwala–Parikh (the default, fitted over coals, biomass, chars and liquids), Dulong, or Boie. The form shows all three for your coal, side by side.
• Formation enthalpy — from the heating value by the combustion cycle, so burning the coal in a Combustor releases exactly that heating value.
• Heat capacity — a measured value, the coal line, or Merrick's model from the analysis, carried as a straight line fitted from 298 to 600 K. The form says how close the line stays to the model.
• Density — a value you enter, or one worked out from the analysis: the organic matter, the pyrite and the other minerals by additive volumes, with the mineral matter from Parr's formula (1.08 × ash + 0.55 × sulfur).

• Feed it through a Solids Feed (mass flows and a particle size distribution), or in a Feed's Nonconventional components (kg/h) beside its gases and liquids.
• Burn it in the Combustor / Furnace, gasify it in the Gasifier, or break it down in the Pyrolyser. The Rotary Dryer, Crusher / Mill, Screen, Cyclone, Kiln and Fluidised-Bed Reactor handle it as a solid.
• A nonconventional component never flashes or distils: it has no molecule, so it has no vapour pressure. It carries mass and enthalpy, and the blocks above turn it into things that do.