By Eamonn Ryan with technical input from Stephen Frewen, refrigeration design engineer: AMC Engineers, Gert van Rooyen, lead applications engineer: HC Group, Robert Kershaw of Barpro, and Eskort.
Eskort, South Africa’s leading pork manufacturer, has expanded its Gauteng production capacity by 50% with a factory extension incorporating a high-tech refrigeration system officially launched in mid-February.
The owners of the processing plant set their sights on having the most energy and operationally efficient plant possible for their expanded pork production. The need stemmed from a desire in increase capacity from the previous 6 000 pigs a week to 9 000.
The 10 000m² development in Heidelberg – the small town where the company has produced world-class pork products for 70 years – will allow Eskort to increase production to meet retail needs.
With the facility processing approximately 5.5 million kilogrammes of meat monthly, maintaining the cold chain integrity is paramount. The enlarged factory is equipped with the largest continuous box freezer in Africa, capable of freezing 120 000kg of products to -18°C every 24 hours. Boxes move on a conveyor belt through the freezing chamber where the air is kept at -31°C – a temperature that occurs naturally only in polar regions.
The chilled and frozen warehouses now have multi-level picking mezzanine floor systems, the first of their kind in the food industry in South Africa. These systems maximise vertical space by including mezzanine floors with mobile racking that create additional levels for storage and picking, and they allow Eskort to handle a high volume of orders quickly and efficiently.
AMC provides cutting-edge refrigeration design in a challenging operational environment.
By Stephen Frewen, refrigeration design engineer: AMC Engineers
Refurbishment projects are inherently challenging, especially when integrating complex additional piping and mechanical systems into an existing, operational refrigeration system. In this case, the refrigeration system capacity was increased from 2850 kWR to 4600 kWR while ensuring minimal downtime for the client’s operations, a priority throughout the project. The project involved multiple complex plant shutdowns, which the refrigeration contractor, PHES, handled effectively, minimising impact on the client’s operations.
The necessity of maintaining uptime for the client’s existing operations influenced every aspect of the refrigeration design. This included compressor technology selection, evaporator positioning and specifications, pipe routing, condenser placement and selection, plant room layouts, and vessel design and sizing.
Key features of the refrigeration design that make it among the best in class refrigerated facilities in South Africa and the world include:
Dedicated outdoor air handling unit (DOAHU): Served by the secondary glycol circuit, the DOAHU tempers fresh air entering the facility, ensuring adequate ventilation for workers and maintaining building health, while removing moisture from the incoming air stream to reduce condensation risk in critical processing areas.
Mechanical dehumidification systems: Equipped with reheat, recovering heat from the refrigeration plant, these systems maintain adequate dew points in key processing areas, reducing surface condensation risk.
Open flash economised screw compressors: Introduced on the low stage of the plant, allowing reuse of existing refrigeration infrastructure while enhancing energy efficiency. The three screw compressors include high-efficiency motors selected by AMC and variable speed drives, significantly improving part-load efficiencies, crucial for abattoir refrigeration design.
Carcass chillers: Featuring floating suction control and fan speed control, these chillers allow the end user to set specific cooling regime recipes, achieving carcass chilling in line with time requirements while minimising moisture loss.
Hot gas and off cycle defrost and freezer pods: All new evaporators were designed to utilise hot gas defrost or off cycle defrost to eliminate the need for electrical elements in defrosting, thereby conserving electrical energy. The large storage freezer features pods that house the evaporators, ensuring that the heat added during hot gas defrost to melt ice on the evaporator is kept out of the storage area. This increases energy efficiency and ensures that product temperatures remain unaffected.
Eskort’s next phase of growth
Arnold Prinsloo, Eskort chief executive officer for the past 17 years, says the core objective of the factory extension is to create efficiencies. “A big part of this expansion includes the addition of carcass chillers as well as the installation of a huge box freezer to accommodate the influx of raw material,” he says.
“This addition doubles our chilled and frozen cold stores, resulting in efficient picking and staging areas and allowing us to eliminate outsourcing costs, and our deboning lines have increased in size to meet the ever-rising demand. We also have new dispatch areas and loading bays to maximise productivity.”
The opening of the factory extension marks the next phase of growth for a company started in the small KwaZulu-Natal Midlands town of Estcourt in 1917. Eskort’s farmers are shareholders in the company creating a closed system where shareholders, predominantly large-scale farmers, also serve as suppliers. Four farms contribute to the facility, located in the vicinity from Bela-Bela to Pretoria, and the pork is antibiotic-free thanks to a massive investment in biosecurity – backed by international and local certification. As a result, its premium export-quality products enjoy the trust of consumers throughout South Africa.
A variety of products are manufactured at the facility, including russians, Gold Medal sausages/pork sausages, and formed products like frikkadels and patties. All value-added products, including pork chops and cooked ribs, are processed and packaged on-site, ensuring quality control and freshness.
Factory general manager Willie Lӧtter describes a highly collaborative process in designing the facility with consulting firm AMC Engineers. Regarding cooling and refrigeration requirements, regulatory obligations dictate temperature control for final product storage, and the new plant is capable of maintaining temperatures consistently at 5°C or below. “A notable addition is a continuous box freezer, the largest in Africa, capable of freezing 120 tonnes of product in a 24-hour cycle. Achieving this required upgrading the refrigeration system to consistently maintain temperatures as low as -40°C,” he explains.
Highlighting the company’s continued presence in Estcourt in KwaZulu-Natal, Lӧtter explains that a processing plant there manages a specific range of products including bacon, viennas and cold meats. “However, the primary processing occurs at the main facility in Heidelberg, where approximately 7 000 pigs are processed weekly.”
Describing their closed system approach, Lӧtter details the stringent protocols observed on supplier farms to ensure biosecurity: “Deliveries occur throughout the week, with processing commencing on Sunday afternoons, and around 1 350 pigs are processed per shift. Following processing is the deboning process which separates raw materials destined for further processing on-site, primarily for bacon and viennas, from those used internally or stored for later use or sale. The comprehensive loop system requires adherence to strict protocols at every stage, from farm to processing facility. Vehicles transporting animals undergo thorough sanitation procedures, and personnel undergo mandatory showers before entering or leaving designated areas. This meticulous approach aims to prevent the introduction and spread of diseases within the facility.
“For safety issues associated with refrigeration systems, there has been a shift towards using glycol-cooled ammonia, a safer alternative to direct ammonia cooling. This approach mitigates risks in the event of spillages, prioritising the well-being of workers. Despite ammonia remaining the primary coolant in the plant room, the incorporation of glycol enhances safety measures,” he says.
While the refrigeration upgrade went uneventfully, Lӧtter lists the primary challenge as being the coordination of the many contractors while keeping the business operational. “Integrating new systems into an operational facility while ensuring uninterrupted production posed significant logistical hurdles. For instance, the expansion of the deboning facility from 120 to 190 tonnes per day required working over a single weekend to avoid disruptions. Managing a workforce of over 2 000 contractors across various disciplines added complexity, necessitating stringent safety measures and logistical oversight.”
While much of this coordination was attributable to consulting engineers AMC, particularly Andrew Minnaar and Stephen Frewen, as well as Krynauw Nienaber and Leon Barnard of Scip Engineering Group, much the load of the day-to-day management of the project fell to the manager and his team, navigating challenges ranging from safety protocols to logistical coordination.
Much of the focus on coordination was due to the unique challenge posed by Eskort’s system wherein shareholders exclusively supply pigs to the facility, which must continue on a daily basis. “Meticulous planning is consequently required to ensure uninterrupted processing. Even during critical maintenance periods, such as the tie-in of refrigeration systems, operations must continue seamlessly to accommodate daily deliveries of thousands of pigs.”
He also noted the involvement of Eskort’s parent company in the genetics sector, contributing to the development of superior pig breeds tailored for modern farming practices, as well as its accreditation for humane animal treatment.
One unique innovation for the South african market was the maximising of vertical space by installing a picking mezzanine level. “These elevated platforms allow for efficient product retrieval, optimising floor space and streamlining operations. Each SKU has a designated pallet position, enhancing organisation and productivity,” says Lӧtter.
He describes this as being revolutionary within the South African meat industry, underscoring its novelty and effectiveness. “The concept originated during the planning stages, with collaboration between Eskort and a company specialising in rack systems. Upon identifying the concept’s viability and success in European facilities, including a firsthand observation in Ireland, Eskort proceeded with its implementation.”
Regarding the refrigeration system’s energy efficiency, Lӧtter stressed the importance of prioritising power security before implementing energy-saving measures to ensure uninterrupted operations. He noted that the facility’s primary challenge was load shedding. To mitigate the impact, Eskort invested in a robust generator park capable of powering the entire site – for uninterrupted power supply of critical processes like continuous freezing – during outages.
“Despite occasional challenges, these measures ensure operational continuity and efficiency, safeguarding both productivity and product quality.”
In addition, to mitigate costs and improve energy efficiency, Eskort implemented various measures, including the installation of energy-efficient motors and sequential systems to manage maximum demand, as well as robust cladding on ducts. Additionally, upgrades to electrical infrastructure, such as overhead cabling, were necessary to accommodate increased power requirements.
Looking to the future, Eskort plans to further reduce diesel consumption by converting generators to run on a mixture of natural gas and diesel. Additionally, the facility’s design incorporates provisions for future solar panel installations to supplement power during daylight hours.
To maintain temperatures post-freezing, frozen meat is immediately transferred to a temperature-controlled holding area. “This process ensures that the meat remains within the desired temperature range before distribution or further processing. The facility’s layout facilitates seamless transitions between freezing and storage areas, optimising workflow and product handling efficiency,” says Lӧtter.
Regarding hygiene protocols, the manager describes the stringent measures in place to prevent contamination and ensure product safety. “Employees undergo rigorous sanitation procedures before entering designated production areas, including changing into specialised clothing and footwear. Furthermore, vacuum-sealed packaging and meticulous labelling procedures enhance traceability and product integrity throughout the production process.”
HC Group delivers advanced refrigeration solutions
Gert van Rooyen, an HVAC&R engineer at HC Group, describes the process as beginning at an early stage in the project lifecycle: “Consultants engage with HC Group to explore various options, ranging from unit sizing to structural considerations and power consumption. This collaborative approach extends to decisions regarding refrigerants, temperature settings, compressor capacities, and component selection, all of which are crucial in achieving efficiency and performance targets.
throughput. ©Cold Link Africa
“Central to HC Group’s approach is the integration of inputs from various suppliers and stakeholders, ensuring a comprehensive understanding of the project requirements.” Van Rooyen emphasises the importance of detailed designs and continuous refinement, highlighting the potential for significant efficiency gains through iterative optimisation.
“Throughout the project lifecycle, flexibility is paramount, as clients may introduce changes or refinements to their specifications which requires agility in adapting to evolving requirements. These are the challenges inherent in managing a dynamic manufacturing process while meeting critical deadlines,” he says. “The nature of large-scale industrial projects is that success hinges on close coordination between all stakeholders and a commitment to continuous improvement.”
The project, he says, was relatively straightforward as the equipment supplied was not particularly complex – it simply required a large number of coils.
In terms of product selection, Van Rooyen emphasises the significance of choosing the right equipment for each application, in this case the significance of selecting the right coils to meet specific capacity and control requirements. “While the selection process may seem routine, there is a deliberate focus on ensuring optimal performance and product quality. Coils play a crucial role in maintaining temperature control and safety, particularly in environments where precision is paramount.”
HC Group’s involvement extends beyond product manufacturing to collaboration with contractors during installation to achieve seamless coordination between all parties to ensure the successful implementation of refrigeration systems. While HC Group does not directly oversee installation, it provides support and expertise as needed, ensuring that any issues are promptly addressed to maintain project timelines.
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