Particle size distribution (PSD), or the distribution of particles over distinct size ranges, in pre-treated organic substrate is relatively unknown, even though it is generally recognised that particle size reduction affects the efficacy of microbial fermentation.When the size of the particles is reduced, biological responses have access to a greater specific surface area. A shorter retention period reduced capital and operational
expenses could also result from smaller particle size distribution, which would be beneficial to remote, rural, and urban regions alike. As a result, the cost of the substrate biomass that must be disposed of is reduced, and a greater percentage of biogas is produced. The study consisted of laboratory tests to reduce particle sizes and analyse the result PSD profile. These techniques were used, like as collected, manual chopping, shredding, grinding, and mincing. Shredders were shown to be less effective at reducing particle sizes for pre-treatment level one when compared to manual chopping and non�treated waste. The fine particle size distribution (PSD) ranges of the non-treated tomato waste were noticeably higher (41%) than those of the other three substrates, such as grass waste 10%< 2.9, banana peel waste 14% <2mm, and paper waste 25% <3mm. The trials showed that, combine effect of mincer, grinder and extending processing time by 5 minutes resulted in
a greater methane output at higher pre-treatment levels with more surface area. The study found that of the four substrate biomass pre-treatment levels, banana peel waste substrate biomass (BPWSB) produced the most methane, at a rate of about 332±36Nml/gVS and a volatile solids reduction (VSR) of 67% for batch tests, while GWSB of semi-continuous tests produced 253 ±29 Nml/gVS. The simulation results and experimental data for different levels of degradability revealed that while large particles decay slowly, a smaller fraction degrades more rapidly. This supports the findings of other studiesin terms of specific surface area, smaller particles had a greater influence on biodegradation than the larger particles.
