0.3–0.5 T/H Biochar Pellet Mill Machine in Kenya

Two Feedstocks Did Not Mean One Recipe

There was one rule from the beginning: coffee-husk char and sawdust-derived char would not be dumped together simply to create a convenient "mixed biochar."

Each material had its own production batch.

Coffee-husk biochar was received, checked, prepared and pelletized according to its condition. When the factory changed to wood-residue biochar, the operating parameters were reviewed again.

That separation mattered because feedstock has a strong influence on biochar properties.

Recent research in western Kenya produced biochar from coffee husk, sugarcane bagasse and wood sawdust under the same pyrolysis conditions and still found clear differences between the resulting chars, including differences in bulk density and porosity.

The customer therefore bought flexibility, not a universal recipe.

Why Build Flexibility Into a Small Plant?

Kenya has diverse biomass resources, but those resources are not distributed evenly.

A 2026 assessment found substantial potentially available crop and forest residues across the country while also showing strong geographical variation in residue type, quantity, density and supply uncertainty. Maize stalks were widespread, whereas other resources were more regionally concentrated.

For a smaller processor, that creates a practical decision.

One option is to build the entire business around a single residue and accept periods when supply becomes less convenient. Another is to qualify several suitable feedstocks and switch production campaigns when required.

This customer chose the second route.

The pellet machine therefore had to be small enough for controlled batch production but industrial enough to move beyond laboratory-scale product development.

The MZLH350 Occupied That Middle Ground

An MZLH320 would have provided only 0.2–0.3 t/h. The MZLH350 increased the working range to 0.3–0.5 t/h without moving the project into a multi-ton-per-hour material requirement that the customer could not guarantee throughout the year.

Project ParameterKenya Configuration
Core Equipment	Biochar pellet mill machine
Model	MZLH350
Main Motor	37 kW
Capacity	0.3–0.5 t/h
Quantity	1 unit
Primary Char	Coffee husk biochar
Alternative Char	Wood-residue / sawdust biochar
Production Method	Separate material campaigns
Project Scale	Small commercial production

This was not a compromise between two machine models. It was a deliberate match to the way the customer sourced material.

The machine could be supplied consistently during a production campaign without requiring the business to accumulate enough char for a 2–4 t/h plant.

Changeover Started Before the Feeder

Switching biochar did not mean emptying one bag and opening another.

Before a new campaign, operators checked the incoming material.

Particle condition came first. Coarse carbonized fragments could not be allowed to create irregular feeding simply because the previous char had been finer. Moisture was checked again rather than inherited from the previous production record.

Binder demand also had to be reassessed.

Coffee-husk char can differ physically from wood-derived char even when both are produced under controlled conditions. A binder and moisture combination that gives acceptable pellet integrity with one material may therefore require adjustment with the other.

RICHI's operating guidance centered on these observations rather than issuing a single setting sheet labelled "biochar."

The Machine Was the Constant; The Process Window Was Not

Once an acceptable batch reached the MZLH350, the mechanical sequence remained familiar.

Prepared material entered through controlled feeding. The rollers forced it through the ring die. Formed strands were cut and transferred for stabilization and screening.

What changed was the operating window.

Feeder rate could require correction. Moisture adjustment could move. Pellet breakage could respond differently. Motor load provided another clue to how the current material was behaving under compression.

Operators recorded those differences by material.

Over time, the customer could build separate operating references for coffee-husk biochar and wood-derived biochar rather than averaging both into settings that were ideal for neither.

Pelletizing Was Only for Material That Passed the Check

Another decision reduced unnecessary production problems: not every batch of char had to be pelletized.

Material with unsuitable contamination, uncontrolled moisture or excessively inconsistent particle condition was held back for correction or another appropriate use.

This prevented the pellet machine from becoming a device expected to repair upstream quality problems.

It also gave the customer a clearer quality-control point.

The inlet specification determined whether the char was ready. The pelletizer then performed densification.

That separation is particularly useful when raw material comes from more than one residue stream.

Agricultural Use Did Not Turn the Machine Into FZLH

Both coffee-husk and wood-derived biochars can be considered for soil-related applications. Kenyan field research has already evaluated locally produced biochars from feedstocks including coffee husks, maize residues and coconut shells in smallholder farming contexts.

But the Kenyan customer's pellets remained predominantly biochar.

There was no substantial composted-manure base or compound organic fertilizer formulation. The MZLH series therefore remained the appropriate route for this case.

If the business later decides to blend biochar heavily with compost, manure or other fertilizer ingredients, RICHI would evaluate that product separately and consider the FZLH fertilizer pellet machine series.

The machine family follows the material formulation, not the fact that a product may eventually be used on farmland.

Small Capacity Made Cleaning and Changeover More Manageable

Multi-feedstock production introduces a practical issue that does not matter as much in a single-material plant: changeover.

The customer needed to avoid leaving unnecessary quantities of the previous char throughout feeding and preparation equipment when switching products.

Production planning therefore included running down the previous batch, clearing relevant material-contact areas and preparing the next char before restarting.

This was not pharmaceutical-grade cross-contamination control. The products were carbon materials.

Still, controlled changeover helped the customer keep batch identity clear and made operating records more meaningful.

If a pellet-quality problem appeared, the team could relate it to the correct raw material instead of an uncontrolled mixture remaining inside the system.

What the Customer Learned from Running Both Chars

The first lesson was simple: a machine capable of processing both materials did not make them behave the same way.

The production team became more confident once it stopped searching for one perfect setting.

Their feedback was:

"We expected to adjust the machine when we changed material, but the useful part was learning what to check before making those adjustments. Now we keep separate production records for each char instead of treating everything as one black powder."

That operating discipline became more valuable than forcing identical output from every batch.

Delivery Through Mombasa

The MZLH350 was shipped by sea from Qingdao Port to Mombasa Port, Kenya.

Before arrival, the customer received the information needed to prepare the machine position, electrical connection and surrounding access. Because production involved material changeovers, the layout also needed practical access to feeding and material-contact areas rather than placing the pelletizer tightly between structures that would make cleaning difficult.

RICHI provided installation guidance, commissioning support and operator training, followed by assistance with normal maintenance, die and roller inspection, lubrication and process troubleshooting.

Kenya Makes the Feedstock Question More Important, Not Less

A recent national assessment estimated that Kenya has diverse crop and forest residue resources with potential for biochar production, but it also warned that plant siting involves trade-offs between residue quantity, density and supply uncertainty.

That makes a flexible project attractive in the right circumstances, but it does not mean every available residue should be fed into one pellet machine.

Each new char still needs evaluation.

Maize-stalk char would not automatically inherit the coffee-husk settings. Sugarcane-bagasse char would require its own assessment. A high-ash material could introduce another set of wear and product-quality considerations.

For this project, RICHI Machinery deliberately limited the initial production plan to two qualified carbonized feedstocks and one appropriately sized MZLH350.

The result was not a "machine for anything." It was a small commercial biochar pellet mill machine that allowed a Kenyan processor to change raw-material campaigns without building its business around one residue source or pretending that different biochars could share one recipe.