Peru’s aquaculture sector, though accounting for only 3% of national fisheries production, is among the fastest-growing in South America. The San Martín region alone contributes 49.4% of the country’s aquaculture harvests, with tilapia production reaching 2,124 metric tons in 2025—an 8.1% year-on-year increase according to Peru’s PRODUCE observatory data released in January 2026. As domestic demand for locally manufactured aquafeed rises, Peruvian feed producers face a critical technical challenge: producing sinking pellets with sufficient water stability for tilapia, a species that feeds slowly at mid-water and bottom levels. This case study documents how a medium-scale tilapia feed mill in Tarapoto, San Martín, partnered with Liyang Hongyang Feed Machinery Co., Ltd. to upgrade its pelleting line with an SZLH420 ring die pellet mill paired with a double-layer conditioner. Within three months of operation, the mill achieved stable production at 3.5 tons per hour, pellet water stability exceeding 22 minutes, and a pellet durability index (PDI) above 96%. The customer reported a 15% reduction in feed waste during pond feeding trials compared to their previous supplier’s pellets.Peru’s aquaculture sector, though accounting for only 3% of national fisheries production, is among the fastest-growing in South America. The San Martín region alone contributes 49.4% of the country’s aquaculture harvests, with tilapia production reaching 2,124 metric tons in 2025—an 8.1% year-on-year increase according to Peru’s PRODUCE observatory data released in January 2026. As domestic demand for locally manufactured aquafeed rises, Peruvian feed producers face a critical technical challenge: producing sinking pellets with sufficient water stability for tilapia, a species that feeds slowly at mid-water and bottom levels. This case study documents how a medium-scale tilapia feed mill in Tarapoto, San Martín, partnered with Liyang Hongyang Feed Machinery Co., Ltd. to upgrade its pelleting line with an SZLH420 ring die pellet mill paired with a double-layer conditioner. Within three months of operation, the mill achieved stable production at 3.5 tons per hour, pellet water stability exceeding 22 minutes, and a pellet durability index (PDI) above 96%. The customer reported a 15% reduction in feed waste during pond feeding trials compared to their previous supplier’s pellets. Peru’s Aquaculture Landscape: Opportunity and Challenge Peru is globally recognized as the world’s largest fishmeal exporter, yet its own aquaculture sector remains underdeveloped relative to its potential. According to Tulio Merino, Manager of the Peruvian National Aquaculture Society (SNA), aquaculture contributes approximately 3% of national fisheries output, with extractive fishing dominating at 97%. However, the sector is bifurcated: technology-driven operations targeting export markets coexist with traditional small-scale farming for regional consumption. Of all aquaculture licenses, 27% belong to AMYPE (micro/small enterprises) and AMYGE (medium/large enterprises) categories, while 73% are held by smaller subsistence-level producers. The Peruvian Amazon—specifically the San Martín, Amazonas, and Loreto departments—is the country’s primary aquaculture zone. Tilapia (Oreochromis niloticus) is the third most harvested species in Amazonian fisheries at 2,124 MT in 2025. Imported tilapia feed prices in Peru range from 0.74 to 1.72 dollars per kilogram (Tridge market data, late 2025), creating a strong economic incentive for local feed manufacturing. For local feed producers, the key quality metric is water stability—the ability of pellets to remain intact underwater without rapid disintegration. Tilapia are slow, intermittent feeders; pellets that break apart within minutes lead to nutrient leaching, water quality deterioration, and increased feed conversion ratios (FCR). The Customer’s Challenge The Tarapoto-based feed mill had been operating an older pellet mill producing 2 to 3 mm sinking tilapia feed. The mill faced three persistent problems: Inconsistent water stability. Pellets from the existing line disintegrated within 8 to 12 minutes in water, well below the industry benchmark of 20 minutes for quality tilapia feed. Root cause analysis pointed to insufficient starch gelatinization during conditioning, the mash spent less than 45 seconds in a single-layer conditioner at temperatures rarely exceeding 80 degrees Celsius. Fluctuating throughput. Hourly output varied between 1.8 and 2.5 tons per hour depending on raw material batch quality, making production planning unreliable and increasing per-ton energy costs. High pellet fines. Fines (dust and broken particles) at the cooler discharge exceeded 8 percent, representing both product loss and a water pollution risk when fines entered pond systems. The mill owner sought a pelleting solution that could deliver consistent throughput, high gelatinization, and durable pellets without requiring a complete line rebuild. Hongyang’s Solution: SZLH420 with Double-Layer Conditioner After technical consultation with Hongyang’s engineering team, the customer selected the SZLH420 ring die pellet mill configured specifically for aquafeed applications. The installation was executed in coordination with the customer’s existing grinding and mixing infrastructure. Equipment Configuration The SZLH420 ring die pellet mill features a 110 kW main motor, 420 mm ring die inner diameter, 120 mm effective width, and operates at 287 rpm. It produces 2.5 mm tilapia sinking feed pellets with a ring die compression ratio of 1:14. The double-layer stainless steel conditioner provides 90 to 120 seconds of retention time at 90 to 95 degrees Celsius conditioning temperature, with steam pressure at 0.2 to 0.4 MPa. Post-conditioning moisture reaches 16 to 18 percent. Why Double-Layer Conditioning Matters for Aquafeed The double-layer conditioner is the differentiating element in this installation. Research published by the Responsible Seafood Advocate (Global Seafood Alliance) confirms that producing highly water-stable pelleted feeds requires mash preconditioning for more than 90 seconds at temperatures exceeding 90 degrees Celsius. Under these conditions, starch granules absorb moisture, swell, and undergo gelatinization—the irreversible rupture of crystalline starch structures that creates a natural binding matrix within the pellet. Hongyang’s double-layer conditioner design provides extended residence time of 90 to 120 seconds through two stacked conditioning chambers, allowing deeper moisture penetration and uniform heat distribution. Precise steam control via modulating valves maintains mash temperature within a plus or minus 2 degrees Celsius band, critical because under-gelatinization leaves pellets brittle while over-conditioning risks nutrient damage. Stainless steel construction with paddle adjustment capability optimizes fill level and retention time for different formulations. Ring Die Selection Rationale The 1:14 compression ratio was selected based on the customer’s formulation—approximately 35 percent starch content from corn and wheat middlings, 28 percent soybean meal, and 22 percent fishmeal. According to industry guidelines (Hengju Machinery technical reference), aquafeed applications require compression ratios between 1:12 and 1:16, with higher ratios producing denser, more water-stable pellets. The 1:14 value was chosen as an optimal balance, verified through Hongyang’s in-house pilot testing with a sample of the customer’s raw material blend. The 2.5 mm die aperture matches the mouth gape of 50 to 200 g juvenile tilapia, the target growth phase for this feed line. Production Results and Data Performance data was collected after a 90-day stabilization period following commissioning. Average throughput improved from 2.1 tons per hour to 3.5 tons per hour, a 66.7 percent increase. Pellet Durability Index (PDI) rose from 89.2 percent to 96.5 percent, a gain of 7.3 percentage points. Water stability (disintegration time) increased from 8 to 12 minutes to 22 to 26 minutes, a 133 percent improvement. Pellet fines at cooler discharge dropped from 8.3 percent to 3.1 percent, a 62.7 percent reduction. Specific energy consumption decreased from 38.5 kWh per ton to 31.4 kWh per ton, saving 18.4 percent. Pellet shaping rate improved from approximately 90 percent to at least 96 percent. The most significant improvement—water stability exceeding 22 minutes—directly translated to field results. The mill’s tilapia farming customers reported a 15 percent reduction in observed feed waste during pond feeding trials over a 30-day period, improved water clarity in intensive pond systems attributed to reduced pellet disintegration and nutrient leaching, and consistent pellet hardness batch-to-batch, which simplified automated feeding system calibration. Operational Stability and Support Beyond the performance metrics, the customer highlighted two operational advantages. First, consistent output across raw material variability: the Peruvian Amazon’s supply chain for feed ingredients—particularly locally sourced cassava meal and rice bran—exhibits batch-to-batch moisture and fiber content variation. The SZLH420′s 110 kW main drive with 287 rpm die speed provides sufficient torque reserve to maintain throughput even when processing higher-fiber batches, while the double-layer conditioner’s adjustable retention time compensates for moisture fluctuations. Second, remote technical support: Hongyang provided WeChat-based real-time troubleshooting during commissioning, guiding the customer’s maintenance team through die break-in procedures, roller gap adjustment (0.1 to 0.3 mm clearance), and steam quality optimization. This remote support model reduced the need for on-site visits, a significant advantage for a facility located in Peru’s interior. Conclusion This case demonstrates that medium-scale aquafeed producers in emerging markets can achieve export-grade pellet quality with properly configured ring die pelleting systems. The combination of the SZLH420 pellet mill’s robust drive platform, a 1:14 compression ratio ring die, and the double-layer conditioner delivering 90 to 120 seconds of high-temperature conditioning produced measurable improvements in throughput, water stability, and pellet durability. For Peru’s growing tilapia aquaculture sector—where the economic case for domestic feed manufacturing strengthens as import prices fluctuate between 0.74 and 1.72 dollars per kilogram—reliable, locally-supported pelleting equipment represents a strategic advantage. Hongyang’s engineering approach, which prioritizes conditioning optimization and die specification matching over simply installing larger motors, aligns with the practical needs of feed mill operators who require production stability above all else. Data sources: Peru PRODUCE observatory report (January 2026); Tridge tilapia feed import data (Q4 2025); Global Seafood Alliance / Responsible Seafood Advocate on Preconditioning Shrimp Feeds technical article; Hengju Machinery ring die selection guide; Hongyang SZLH420 technical specifications.
Post time: Jun-01-2026
