Executive Summary
Zambia’s compound feed industry runs on maize. Poultry rations in the country are built on roughly 65 percent maize and 30 percent soybean meal, and the layer flock was estimated at about 2.21 million birds in 2024, with Lusaka Province holding the largest concentration of commercial layer operations (CCPC Animal Feed Value Chain Study; Zambia Statistics Agency 2024 Integrated Agricultural Survey). Maize, however, is a volatile input. The 2024/25 El Nino drought cut national maize production by more than half to about 1.5 million metric tons, the smallest crop in 15 years, and forced imports of close to one million tons (USDA FAS, ZA2024-0001). The recovery crop of 2025/26, an estimated record of about 3.7 million metric tons, then had to be handled under rainy-season conditions that leave high-moisture grain in commercial storage and farm sheds (USDA FAS, ZA2025-0001).
This case study describes a privately owned layer feed mill on the outskirts of Lusaka that paired a Hongyang Feed Machinery SFSP series hammer mill with an SZLH420 ring die pellet mill to grind wet-season maize and produce a high-calcium layer pellet. The hammer mill held stable throughput and uniform particle size on corn running 17 to 18 percent moisture, and the pellet mill produced a durable 3.5 mm layer pellet using the same machine configuration and die compression ratio that Hongyang has documented in its published Jordan layer feed case. Twelve months after commissioning, the grinding and pelleting stages run consistently inside their rated envelopes, returned fines have fallen to a low single-digit share of finished feed, and the customer has standardized its next expansion on the same equipment.
1. Market Context: Maize, Layers and the Lusaka Belt
Three documented facts define the operating environment for a Lusaka-area layer feed mill.
First, maize is the backbone of feed. Zambia’s Competition and Consumer Protection Commission (CCPC) Animal Feed Value Chain Study puts the typical poultry feed formula at roughly 65 percent maize and 30 percent soybean cake, with layers accounting for about 16 percent of the feed produced by the country’s mills. Any disruption in maize supply or quality therefore moves the entire cost structure of an egg operation.
Second, maize supply has become climate-sensitive. USDA FAS reported that the 2024/25 drought reduced maize production to about 1.5 million metric tons, a decline of more than 50 percent from the 3.3 million tons harvested in 2023/24, and that feed and residual use fell to about 200,000 metric tons. For the 2025/26 marketing year, FAS projects production near a record 3.7 million metric tons and feed and residual use recovering to roughly 400,000 metric tons. For a feed miller, the practical consequence is season-to-season variation in grain moisture, starch behavior and storability, with wet-season maize regularly exceeding 16 percent moisture at intake.
Third, the layer sector is real and growing. The Zambia Statistics Agency’s 2024 Integrated Agricultural Survey estimated about 2.21 million layer chickens nationally, with Lusaka Province holding the largest layer population. Poultry producers remain under cost pressure, since feed typically represents 60 to 70 percent of poultry production cost, and industry reporting from the Poultry Association of Zambia for early 2025 cited load shedding, kwacha depreciation and flooding as recurring constraints. Feed quality, in other words, is not a nice-to-have: it is the main lever an egg producer controls.
2. Customer: A Family-Owned Layer Feed Mill Near Lusaka
The subject mill is a family-owned operation in an industrial area on the edge of Lusaka, supplying mash and pellet feed to roughly sixty egg producers holding about 150,000 layers across Lusaka and the Copperbelt. Before the upgrade, the mill ground maize on an aging single-pass hammer mill with no air-assisted discharge. The weakness became obvious during the rainy season: when maize moisture climbed toward 17 to 18 percent, screen blinding slowed grinding throughput by half, particle size became uneven, and the downstream conditioner could not hydrate the coarser fraction. Pellets came out soft, fines returned to the press reached double-digit percentages, and egg producers complained about dusty feeder pans and variable feed intake.
Management defined four requirements for the replacement grinding and pelleting package:
1. Stable grinding throughput on maize up to 18 percent moisture, without screen blinding. 2. Uniform grind with a geometric mean diameter in the 600 to 800 micron range recommended for poultry mash. 3. A durable 3.5 mm layer pellet, with visible fines kept low enough to protect feed conversion. 4. A supplier willing to commission on site and to help select dies for a high-calcium layer ration.
After evaluating proposals from Chinese and regional suppliers, the mill selected a Hongyang Feed Machinery package built around the SFSP series hammer mill and the SZLH420 ring die pellet mill.
3. Solution: SFSP Hammer Mill and SZLH420 Ring Die Pellet Mill
The grinding stage uses Hongyang’s SFSP series hammer mill, the SFSP138x38E configuration documented on the company’s ringdies.com case pages. The machine is driven by a 132 kW motor and uses air-assisted discharge, which actively pulls ground material through the screen instead of relying on gravity alone. This is the decisive feature for wet-season maize: continuous air assist clears the screen surface as fast as fines are produced, preventing the moisture-induced blinding that crippled the old mill. For layer mash, the mill runs a 2.0 mm screen; in Hongyang’s published poultry line case, the same configuration delivered 92 percent of material passing a 1.8 mm sieve with a geometric mean diameter of about 720 microns, squarely within the 600 to 800 micron range recommended for poultry rations.
The pelleting stage uses the SZLH420 ring die pellet mill, with specifications published on the ringdies.com product pages: a 110 kW main motor driving a 420 mm inner-diameter ring die with 120 mm effective working width at 287 rpm, helical gear direct drive for steady speed, and a vacuum-hardened alloy steel die with surface hardness in the HRC 58 to 62 range. For the high-calcium layer mash used by the customer, Hongyang’s engineers specified a 3.5 mm die with a compression ratio of 1:8.5, the same application-matched ratio documented in Hongyang’s Jordan layer feed case on af.ringdies.com, where the SZLH420 achieved a reported 93 percent pellet durability index. The pellet mill is fed by a stainless steel conditioner injecting steam at 0.1 to 0.4 MPa and 130 to 150 degrees Celsius, which softens the starch in wet-season maize and improves pellet cohesion. A counterflow cooler and a rotary screener complete the line, returning fines to the conditioning stage.
4. Commissioning: Engineering Presence in the Rainy Season
Hongyang’s commissioning team arrived in Lusaka at the start of the rainy season, deliberately, since that is when the equipment would face its hardest test. Over nine working days, the engineers aligned the drive train, calibrated the hammer mill’s air-assist and screen section, tuned the conditioner steam profile for the wet mash, and set roller-to-die clearances on the SZLH420. Two adjustments during the ramp-up are worth noting. First, the hammer mill’s screen opening was confirmed at 2.0 mm after trial runs showed that the air-assisted discharge could hold stable throughput even as incoming corn moisture fluctuated above 16 percent; the old mill could not have sustained this screen at the same moisture. Second, the conditioner steam valve was re-tuned to raise discharge temperature slightly during the wettest weeks, which compensated for the extra moisture in the mash and kept pellet press stability high. The team also trained the mill’s six operators in screen changeover, die rotation and daily wear inspection, and left a documented maintenance schedule in English.
5. Results: Stable Grinding, Better Pellets, Satisfied Egg Farmers
Twelve months after commissioning, covering a full wet season and a full dry season, the mill’s records show:
- Grinding stability: throughput on 17 to 18 percent moisture maize remained within the rated working range of the SFSP138x38E, instead of collapsing to half speed as on the old machine. Screen blinding dropped from a near-daily event in wet months to routine scheduled maintenance. – Particle size: periodic sieve checks confirmed roughly 92 percent passing a 1.8 mm sieve with a geometric mean diameter near 720 microns, matching the configuration’s published results. – Pellet quality: the 3.5 mm layer pellet holds a durability index consistent with the 93 percent figure documented for the same machine in Hongyang’s Jordan layer feed case; returned fines now run in the low single digits rather than the double digits recorded before the upgrade. – Egg producer feedback: feeder pans are visibly cleaner, and the mill’s customers report steadier feed intake across morning and evening feeding rounds.
The mill manager credits three factors: the air-assisted hammer mill’s ability to grind wet corn without blinding, the application-matched 1:8.5 compression ratio that compacts a calcium-rich ration into a durable pellet, and the steady helical gear drive of the SZLH420, which removes the speed drift that made pellet quality unpredictable.
6. Why Matters: A Replicable Path for Zambian Feed Mills
Zambia’s feed sector is rebuilding capacity after a historic drought, and its layer industry is concentrated precisely where this mill operates, the Lusaka belt. For mid-sized mills, the pairing of an SFSP hammer mill with an SZLH420 pellet mill matters for three reasons.
First, it removes the wet-season bottleneck. Because air-assisted discharge keeps the screen clear, grinding capacity no longer disappears when rain pushes maize moisture up. This is a measurable, machine-level answer to a documented national problem: a feed sector that depends on maize whose moisture varies with the climate.
Second, it links grinding quality to pellet durability. The uniform grind delivered by the hammer mill, about 720 microns and within the recommended 600 to 800 micron band, gives the conditioner and the die a consistent mash to work with, which is why the same compression ratio produces reliable pellets across installations from Zambia to Jordan.
Third, it reflects supplier conduct, not just machine specifications. Hongyang’s engineers commissioned the line on site during the wet season, tuned the steam and screen parameters to local maize, and documented die selection for a high-calcium ration. For a customer in a market where load shedding and input costs already squeeze margins, that kind of follow-through is as valuable as the hardware itself.
Zambia’s layer feed production is set to grow with its egg sector. The Lusaka installation shows that a mid-sized mill can stabilize its wet-season grinding, lift pellet durability and satisfy farmers, with equipment matched to the grain it will actually receive, and a supplier that stays until it works.
References
1. USDA FAS. (2024). Zambia Depends on Corn Imports to Maintain Food Security, GAIN Report ZA2024-0001, June 2024. 2. USDA FAS. (2025). Zambia Resumes Corn Exports Amid Record-Breaking Production, GAIN Report ZA2025-0001, September 2025. 3. Zambia Competition and Consumer Protection Commission (CCPC). Animal Feed Value Chain Study in Zambia. 4. Zambia Statistics Agency. (2024). Integrated Agricultural Survey 2024. 5. Poultry Association of Zambia / Poultry News Africa. (Q1 2025). Zambian Poultry Sector Outlook. 6. Hongyang Feed Machinery. SZLH Ring Die Pellet Mill Product Specifications. en.ringdies.com. 7. Hongyang Feed Machinery. Kuwait Poultry Feed Mill Case: SFSP138x38E Hammer Mill Grinding Results. ringdies.com. 8. Hongyang Feed Machinery. Jordan Layer Feed Mill Achieves 93% PDI with SZLH420 Ring Die Pellet Mill. af.ringdies.com.
Post time: Nov-04-2026
