200-300 KG/H Coffee Husk Pelletizing Machine in Colombia

The Project Had to Start at the Correct Stage of Coffee Processing

Colombia is one of the world’s most important washed Arabica producers. In that processing system, fresh coffee cherries are normally pulped at or near the farm, generating wet pulp and mucilage. The beans then continue through fermentation or demucilaging, washing, drying, and storage as parchment coffee.

Only later, during dry milling, is the parchment layer removed from the dried coffee bean.

That dry, lightweight fibrous residue is what this biomass pellet project refers to as coffee husk or cisco.

This avoids a common technical mistake: treating coffee pulp, coffee cherry husk, parchment, and dry-mill cisco as though they were the same material with the same moisture, chemical composition, and processing requirements.

Why a Dry Mill in Huila Made More Sense Than a 200-Hectare Farm

Huila is one of Colombia’s major coffee-producing departments, but individual farms generally do not generate large quantities of dry-mill cisco because many growers sell parchment coffee rather than operating their own commercial dry mills.

The customer in this project aggregates coffee from multiple member farms.

That gives the cooperative a much more concentrated supply of dry husk after hulling and grading. The pelletizer can therefore operate in planned campaigns instead of waiting for enough material from one plantation.

This scale is better matched to one 22 kW MZLH320 than a small individual farm whose primary residue would actually be wet coffee pulp.

Coffee Husk Already Had Value before Pelletizing

The cooperative did not describe cisco as a useless waste.

In Colombian coffee processing, dry coffee husk has already been recognized as a useful biomass fuel, particularly for mechanical coffee drying. The commercial question was therefore whether densification would improve the way the cooperative handled and used a portion of that fuel.

Loose cisco has very low bulk density. It occupies substantial storage volume, creates dust during transfer, and can be difficult to meter at a stable rate into smaller automatic fuel-feeding systems.

Pelletizing changes those physical characteristics.

The cooperative gains a denser, more uniform fuel that is easier to bag, store, convey, and dose. The project is therefore better understood as fuel upgrading rather than waste disposal.

The Raw Material Arrives Dry, but It Still Needs Preparation

Coffee husk leaving a dry-milling process is considerably different from fresh coffee pulp.

It is already relatively dry, lightweight, and fibrous. However, the material still contains variation in particle size, dust content, and occasional foreign matter from handling.

Before pelletizing, the cooperative screens the cisco and removes unsuitable contaminants. A magnetic protection stage is used where necessary to prevent accidental metal from reaching the biomass pellet mill.

The material then passes through controlled grinding so that oversized fibrous pieces are reduced and the feed entering the pelletizer has a more uniform particle distribution.

The MZLH320 biomass pellet machine  is not used as a primary grinder.

Moisture Is Checked before Every Production Campaign

The customer does not assume that dry coffee husk always arrives at one fixed moisture percentage.

Cisco stored under good dry-mill conditions can already be close to a workable pelletizing range. Material exposed to humid air or poor storage can regain moisture, while excessively dry material can generate more dust and may require controlled adjustment before densification.

The operator therefore checks moisture before production.

If the material is already suitable, unnecessary drying is avoided. If conditions have changed during storage, moisture is corrected before the feed enters the ring die.

The final setting is determined from feeding stability, motor load, pellet strength, and cooling behavior rather than one permanent number printed on an operating sheet.

The MZLH320 Was Large Enough for the Cooperative’s Actual Husk Stream

At approximately 0.25 T/H, a six-hour production campaign can convert roughly 1.5 tonnes of prepared material.

For the cooperative, this is enough to process selected cisco batches without creating an oversized pelletizing section that would remain idle for much of the year.

A larger MZLH420 or MZLH520 would have required substantially more continuous husk supply and higher downstream fuel demand.

Why 6 mm Was Chosen

The cooperative selected 6 mm pellets for the main fuel product.

The choice was based on handling and feeder compatibility rather than the idea that smaller pellets automatically burn better.

Six-millimeter pellets are easy to convey, store, and meter through compact fuel-feeding equipment. Moving to a smaller die diameter would increase compression resistance and could reduce throughput, while a larger diameter was unnecessary for the customer’s existing fuel systems.

The project therefore standardized one diameter instead of routinely changing among 4, 6, and 8 mm products.

The Ring Die Was Configured for Coffee Husk, Not Copied from Sawdust

Coffee husk does not behave exactly like wood sawdust.

Its fiber structure, ash content, bulk density, and natural composition create a different compression response inside the die.

During commissioning, the cooperative evaluated the relationship among feed rate, motor current, die temperature, pellet surface, and mechanical durability.

If the die creates excessive resistance, production falls and power consumption rises. If compression is too low, pellets can fracture during cooling and handling.

The final die specification was therefore selected around the actual Colombian cisco rather than using a generic wood-pellet setting.

There Is No Need to Turn This Material into Fertilizer Just because It Comes from Coffee

The cooperative also composts other organic residues, including coffee pulp generated by some member farms, but that material belongs to a separate process.

Wet coffee pulp can be composted and returned to agricultural soils under appropriate management.

Dry-mill coffee husk has a different physical condition and an established energy-use pathway.

For this project, the MZLH320 is dedicated to fuel pellets. The cooperative does not pelletize the same material and advertise it simultaneously as fuel, fertilizer, animal feed, and soil amendment.

Keeping one clear application makes operating settings and product quality easier to control.

Pelletizing Does Not Automatically Increase the Fuel’s Heating Value

Densification changes density and handling characteristics; it does not create additional energy inside the biomass.

The heating value of the finished product is determined primarily by the coffee husk itself and its moisture and ash content.

The advantage is that more fuel mass can be stored in a given volume and delivered more uniformly into a combustion system.

This is especially useful when the cooperative wants a predictable fuel feed rather than intermittent manual loading of loose cisco.

Ash Still Matters

Coffee husk is not identical to premium clean-wood fuel.

Its mineral and ash characteristics have to be considered when selecting the combustion system and maintenance schedule.

The cooperative therefore tests representative production batches instead of assuming that every 6 mm biomass pellet can be burned in the same equipment.

Moisture, ash, calorific behavior, fines, and pellet durability are among the practical characteristics checked before expanding use in another thermal system.

The Customer Uses the Pellets Where Their Handling Advantage Matters

Loose cisco remains useful in applications where a boiler is already designed for it and storage space is not a major constraint.

The cooperative therefore does not pelletize every kilogram of husk it produces.

Pelletizing is reserved for applications where the denser format provides a clear operational benefit: controlled feeding, smaller storage volume, cleaner handling, bagged reserve fuel, or transport to another compatible thermal user.

This prevents the project from adding electrical consumption where densification does not create enough value.

The Coffee Dryer Was the First Thermal User

The most logical initial consumer was inside the coffee business itself.

The cooperative uses mechanical drying during periods when solar drying alone cannot provide enough capacity or weather conditions are unfavorable.

Using a densified fuel made from the dry-mill by-product creates a practical internal biomass loop: the coffee processing operation produces cisco, part of that cisco is densified, and the fuel can then support controlled thermal drying of coffee.

The customer can still use other approved biomass fuels when required.

Cooling Is Required before the Pellets Enter Storage

Fresh pellets leave the ring die warm and are not immediately sealed into bags.

The cooperative uses a small downstream cooling section to bring the product closer to ambient conditions and allow its structure to stabilize.

After cooling, loose fines are screened out.

Clean reusable fines can return to the preparation stage where appropriate.

This reduces dust in the finished fuel and improves handling through the customer’s storage and feeding equipment.

Why the Existing Drying Patio Was Not Treated as a Coffee-Husk Dryer

The original project concept assumed that a coffee drying patio could simply be used to dry large amounts of husk.

For the revised project, that is not the central process assumption.

The customer is handling cisco from dry milling, which is already a dry-process residue. The main requirement is keeping it protected from rainfall and ambient moisture after separation.

A drying patio may still be useful for other coffee-processing materials, but it is not presented as an essential industrial pretreatment stage for this pelletizer.

Huila’s Coffee Industry Provides the Right Customer Base

The project works because the customer is connected to a substantial coffee-growing region and aggregates parchment coffee from many producers.

The machine’s raw-material supply therefore depends on dry-mill throughput rather than on the hectare count of one estate.

This also creates a more realistic annual operating pattern. Pellet production follows the cooperative’s milling and storage schedule, with heavier campaigns when sufficient cisco has accumulated.

The MZLH320 does not need to run continuously throughout the calendar year to justify the investment.

The First Operational Bottleneck Was the Low Bulk Density of Cisco

After installation, the production team found that the challenge was not crushing resistance.

The coffee husk was so light that inconsistent hopper loading could make the pellet mill appear unstable even though the ring die itself was operating normally.

The arch-breaking and forced-feeding system therefore became particularly important.

Operators adjusted feeder speed according to bulk density and material condition instead of trying to maintain one fixed setting for every batch.

Once feeding became stable, main-motor load and pellet output also became more predictable.

Maintenance Depends Heavily on Material Cleanliness

Cisco itself is not an extremely abrasive material, but dirt and mineral contamination can accelerate wear.

The cooperative therefore keeps the dry-mill residue off the ground and protects storage areas from soil contamination.

Ring die and roller condition are inspected according to actual production behavior rather than replaced after an arbitrary number of tonnes.

Changes in current draw, throughput, pellet surface, die temperature, and fines level are used to decide when maintenance is required.

Shipping from Qingdao to Colombia

The MZLH320 was exported from Qingdao Port in China to Colombia through Buenaventura on the Pacific coast, followed by inland transport to the customer’s facility in Huila.

Before shipment, RICHI provided equipment dimensions, motor information, foundation requirements, electrical documentation, feeder and discharge interface data, and recommended maintenance clearance.

This allowed the cooperative to prepare the machine position and supporting equipment before arrival.

The logistics section was planned around confirmed freight arrangements rather than relying on a fixed number of ocean-transit or customs-clearance days.

What the Cooperative Learned after the First Production Campaigns

“We originally thought our main challenge would be pressing such a light material into a dense pellet. The bigger issue was feeding the coffee husk evenly. Once we controlled particle size, storage moisture, and feeder speed, the pellet mill became much more predictable. We now densify the cisco when the pellet form gives us a clear handling advantage instead of trying to pelletize every tonne we produce.”

That operating philosophy also improved economics.

The cooperative no longer evaluates success only by how many tonnes pass through the pellet machine. It compares electricity consumption, storage volume, fuel-handling labor, fines generation, and the value of densification for each intended thermal application.

Coffee Husk Pelletizing Machine in Colombia for Dry-Mill Biomass Fuel

This coffee husk pelletizing machine in Colombia project is based on a specific residue from Colombia’s coffee-processing chain: dry coffee husk, or cisco, produced when parchment coffee is hulled during dry milling.

The Huila cooperative uses one MZLH320 with a 22 kW main motor, 2.2 kW arch-breaking feeder, 0.75 kW forced feeder, and 320 mm ring die. The machine produces 6 mm densified fuel at a reference capacity of approximately 0.2–0.3 T/H under suitable material conditions.

The project does not confuse cisco with wet coffee pulp, does not claim that pelletizing increases nutrient value or calorific value, and does not force every coffee residue into the same application. Loose husk remains useful where existing combustion systems can handle it efficiently; pelletizing is used where higher bulk density, controlled feeding, cleaner storage, and transportability create an operational advantage.

For another customer considering a coffee husk pelletizing machine in Colombia, RICHI Machinery would first determine exactly which coffee residue is available, where in the processing chain it is generated, annual dry quantity, moisture, ash and contamination, existing grinding and storage equipment, target pellet diameter, intended thermal user, daily operating hours, cooling method, and electrical supply before selecting the machine.

That distinction is essential in coffee projects. Coffee pulp, mucilage, parchment, cisco, and dry cherry husk may all be described casually as “coffee waste,” but they are not interchangeable materials. The correct pelletizing solution begins by identifying which one the customer actually has.