The question is about determining the effective particle size of biomass for a thermochemical process. can the same method of determining the fineness modulus of sand for fine, medium and coarse sand be considered here?
I do not understand the purpose of determining the particle size. Nevertheless, using sieve would not be the best, because the process may even alter the size or shape. Allowing the particles to drop in a tube, or remain suspended and determination by non-intrusive optical means would provide a representative value.