Executive Summary
Greece is the largest producer of farmed sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) in the European Union. According to the Hellenic Aquaculture Producers Organization (HAPO) Annual Report 2025, the combined production of these two species reached 114,500 tons in 2024, generating €721 million in sales value. Approximately 82% of this production was exported to 38 markets outside Greece, underscoring the sector’s strategic importance to the national food trade balance.
For Greek feed mills supplying this demanding industry, pellet quality is not merely a technical specification — it is a commercial necessity. Export buyers in Italy, Spain, France, and the Middle East evaluate feed pellets on hardness, sinking rate, water stability, and nutritional uniformity. A single substandard batch can erode relationships cultivated over years.
This case study examines how a mid-sized Greek aquafeed manufacturer overcame persistent pellet quality and throughput challenges by adopting a Hongyang SZLH series ring die pellet mill system. The results — 6.5 metric tons per hour of stable output, pellet durability index above 97%, and water stability exceeding 120 minutes — demonstrate that purpose-built Chinese feed machinery can meet the exacting standards of Mediterranean aquaculture.
The Greek Aquafeed Landscape and Customer Profile
Industry Context
Greece’s aquaculture sector is distinguished by several characteristics that directly shape feed mill requirements:
- Species specialization: Sea bass and sea bream account for over 90% of national farmed fish output. These carnivorous species require high-protein (42–48% crude protein), high-fat sinking pellets with diameters typically ranging from 2.0 mm to 6.0 mm.
- Export-driven quality standards: With 82% of production exported, Greek feed must satisfy diverse international buyer specifications. Feed that performs adequately in Greek waters may fail under different farming conditions in importing countries.
- Climatic and logistical reality: Greek feed mills operate in a Mediterranean climate with hot, dry summers. Pellet stability during storage and transport across the Aegean Sea to island-based cage farms is a critical operational concern.
The Customer
The customer — referred to here as “MedFeed S.A.” to respect commercial confidentiality — is a family-owned feed manufacturer based in Central Greece, approximately 40 km from the port of Volos. Founded in 2002, the company began as a small-scale supplier for nearby fish farms and has since grown to serve over 20 cage-farming operations across the Aegean and Ionian Seas.
Prior to the Hongyang installation, MedFeed operated a European-made pellet mill that had served adequately for over a decade. However, as the company expanded its customer base and export volume, three interrelated problems emerged:
- Declining throughput: The aging machine struggled to maintain consistent output above 4.0 t/h on 4.0 mm sea bream sinking feed, forcing overtime shifts during peak demand periods (April through September).
- Pellet quality inconsistency: Pellet Durability Index (PDI) varied between 91% and 96% across batches, with fines generation sometimes exceeding 8%. Customers began flagging excessive dust in delivered feed bags.
- Water stability complaints: Sinking pellets for sea bass — which must remain intact on the cage floor for at least 60 minutes to allow full consumption — occasionally disintegrated prematurely, leading to feed waste and customer dissatisfaction.
Procurement Decision and Selection Process
Why a Chinese Ring Die Pellet Mill?
MedFeed initially planned to source a replacement pellet mill from a well-known European OEM. The quotation exceeded €380,000 for a machine of comparable capacity, with a delivery lead time of 22 weeks. The company’s production manager, Mr. Dimitris A., had previously visited a Greek feed mill that had installed a Danish-made pellet mill — and was aware of both the price premium and the maintenance complexity.
In early 2024, MedFeed’s procurement team attended the annual Aquaculture Europe conference, where they encountered a presentation on ring die pellet mill technology from China. Intrigued, they initiated contact with three Chinese manufacturers, including Liyang Hongyang Feed Machinery Co., Ltd.
Why Hongyang?
Hongyang’s technical proposal distinguished itself in several ways:
- Ring die compression ratio customization: Hongyang’s engineers analyzed MedFeed’s specific feed formulation — which includes 25% fishmeal, 18% soybean meal, 12% wheat gluten, and 8% fish oil — and recommended a compression ratio of 1:10.5 for the 4.0 mm sea bream die and 1:11 for the 6.0 mm sea bass die. Competing Chinese suppliers offered generic compression ratios without formulation-specific analysis.
- Double-layer conditioner integration: Recognizing that starch gelatinization is critical for sinking pellet water stability, Hongyang proposed pairing the SZLH pellet mill with a double-layer conditioner providing 120–180 seconds of retention time at 85–90°C. This was a configuration not offered by the other Chinese suppliers at a comparable price point.
- Roller shell metallurgy transparency: Hongyang provided detailed material certification for the roller shells (20CrMnTi alloy steel with carburizing treatment), including surface hardness specifications (HRC 58–62) and expected service life under MedFeed’s operating parameters. This level of documentation built trust during the evaluation phase.
After a three-month evaluation that included reference calls with existing Hongyang customers in Southeast Asia and a factory visit to Liyang, MedFeed placed an order for one SZLH608 ring die pellet mill with double-layer conditioner in June 2024. The total investment — including the conditioner, auto-lubrication system, and spare ring die set — was approximately 55% of the European OEM quotation, with a delivery time of 10 weeks.
Installation and Commissioning
The SZLH608 system arrived at MedFeed’s facility in late August 2024. Hongyang dispatched a two-person commissioning team — one mechanical engineer and one electrical engineer — who remained on-site for 12 days.
Key milestones during commissioning:
- Mechanical alignment: The main motor (160 kW, 6-pole) and the ring die assembly were aligned to a tolerance of 0.03 mm, verified by laser alignment tooling.
- Steam system calibration: The double-layer conditioner was integrated with MedFeed’s existing steam boiler (1.2 t/h capacity). Hongyang’s engineer tuned the steam pressure to 0.4 MPa and verified that the conditioner jacket maintained 88°C ± 2°C under continuous operation.
- Load testing: Over three days, the system was tested on three formulations — 2.0 mm sea bass starter feed, 4.0 mm sea bream grower feed, and 6.0 mm sea bass finisher feed. All three formulations achieved target throughput within the first 48 hours of testing.
Operational Results
Throughput Stability
MedFeed recorded production data over a six-month period from September 2024 through February 2025. The SZLH608 consistently delivered:
Feed Type: Sea bass starter (2.0 mm) — Target: 4.5 t/h | Actual: 4.3 t/h | Energy: 18.2 kWh/t
Feed Type: Sea bream grower (4.0 mm) — Target: 6.0 t/h | Actual: 6.5 t/h | Energy: 14.8 kWh/t
Feed Type: Sea bass finisher (6.0 mm) — Target: 7.0 t/h | Actual: 7.2 t/h | Energy: 13.1 kWh/t
The 6.5 t/h figure on 4.0 mm sea bream grower feed represented a 62.5% improvement over the previous pellet mill’s 4.0 t/h. Monthly production capacity increased from approximately 720 tons to 1,100 tons, allowing MedFeed to eliminate overtime shifts entirely.
Pellet Quality Metrics
Third-party laboratory testing (conducted by an Athens-based feed analysis laboratory) on three random production samples in November 2024 yielded the following results:
2.0 mm Sea Bass Starter: PDI: 97.2% | Fines: 1.8% | Water stability: 125 min | Bulk density: 620 g/L
4.0 mm Sea Bream Grower: PDI: 97.8% | Fines: 1.4% | Water stability: 135 min | Bulk density: 640 g/L
6.0 mm Sea Bass Finisher: PDI: 98.1% | Fines: 1.1% | Water stability: 148 min | Bulk density: 655 g/L
The water stability values — exceeding 120 minutes across all pellet sizes — were particularly significant. MedFeed’s largest customer, a sea bass cage farm operator with 12 cages in the Pagasetic Gulf, reported a noticeable reduction in visible feed waste during feeding operations. The farm’s feed conversion ratio (FCR) improved from 1.52 to 1.47 over the four-month observation period, which the farm manager attributed in part to reduced pellet disintegration.
Operational and Economic Impact
Beyond the technical metrics, several operational benefits emerged:
- Die service life: The first ring die set (10.5 compression ratio, 4.0 mm) processed approximately 3,800 tons before showing measurable wear — consistent with Hongyang’s projected 3,500–4,500 ton lifespan for aquafeed formulations.
- Energy efficiency: The average energy consumption of 14.8 kWh/t on the 4.0 mm formulation was 9% lower than the previous machine’s 16.3 kWh/t, translating to annual electricity savings of approximately €4,200 at Greek industrial electricity rates.
- Maintenance accessibility: MedFeed’s maintenance team reported that roller shell replacement — a task required every 800–1,000 operating hours — could be completed in under 90 minutes with two technicians, compared to 3+ hours on the previous machine.
Customer Feedback
In a December 2024 follow-up call, Mr. Dimitris A. provided direct feedback:
We were cautious about sourcing a pellet mill from China. Our industry in Greece has historically relied on European and Scandinavian equipment. But the Hongyang machine has exceeded our expectations. The water stability improvement alone has strengthened our position with export buyers. When our Italian customer visited our plant in November, they specifically commented on the pellet hardness and uniformity. That kind of validation matters.
MedFeed’s export manager added that the consistent pellet quality had simplified their quality assurance documentation for EU border inspections — a non-trivial operational advantage.
Conclusion
MedFeed’s experience illustrates a pattern observed across multiple Hongyang aquafeed installations: that well-engineered Chinese ring die pellet mill technology, when properly specified and commissioned, can deliver performance metrics that meet or exceed those of more expensive European alternatives.
For the Greek aquaculture sector — which faces intensifying competition from Turkish and Egyptian producers — access to cost-effective, reliable feed processing equipment is a meaningful competitive lever. The SZLH series ring die pellet mill, with its formulation-specific compression ratio engineering and integrated conditioning system, offers a viable path to improving pellet quality while containing capital expenditure.
Hongyang’s approach — combining metallurgical transparency, on-site commissioning support, and ongoing technical consultation — reflects a supplier philosophy that prioritizes long-term operational partnership over transactional equipment sales. For an industry where pellet quality directly translates to fish growth, feed conversion, and ultimately profitability, that philosophy carries tangible value.
Data sources: Hellenic Aquaculture Producers Organization (HAPO) Annual Report 2025; MedFeed S.A. production records (September 2024 – February 2025); third-party feed analysis laboratory reports (Athens, November 2024). Customer name anonymized at company request.
Post time: Jun-12-2026
