Dairy Processing Equipment Design

Understanding Dairy Processing Equipment Design in Atlantic Canada

The dairy processing industry in Atlantic Canada represents a vital component of the region's agricultural economy, with Nova Scotia alone producing over 170 million litres of milk annually. As consumer demands evolve and food safety regulations become increasingly stringent, the design and engineering of dairy processing equipment has become more sophisticated than ever. Professional engineering services play a critical role in ensuring that dairy facilities operate efficiently, safely, and in compliance with Canadian Food Inspection Agency (CFIA) standards.

Dairy processing equipment design encompasses a broad spectrum of engineering disciplines, including mechanical, process, structural, and automation engineering. From small artisanal cheese operations in the Annapolis Valley to large-scale fluid milk processing facilities in the Maritimes, each project presents unique challenges that require customised engineering solutions tailored to specific operational requirements and regulatory frameworks.

Critical Components of Dairy Processing Systems

Modern dairy processing facilities rely on interconnected systems that must work in harmony to transform raw milk into safe, high-quality products. Understanding these components is essential for effective equipment design and facility planning.

Receiving and Storage Systems

The journey of milk through a processing facility begins at the receiving bay, where raw milk arrives from farms across the region. Engineering considerations for receiving systems include:

• Tanker connection points designed for sanitary coupling with CIP (Clean-in-Place) compatibility

• Flow measurement systems capable of accurately measuring deliveries ranging from 5,000 to 50,000 litres

• Preliminary filtering systems with mesh sizes typically between 100-150 microns

• Temperature monitoring to ensure milk arrives below 4°C as required by Canadian regulations

• Sampling systems for quality testing including somatic cell count and antibiotic residue detection

Raw milk storage tanks, often referred to as silos, require careful engineering attention. These vessels typically range from 20,000 to 200,000 litres in capacity and must maintain temperatures between 2-4°C. The design must account for proper agitation to prevent cream separation while avoiding excessive shear that could damage fat globules. In Nova Scotia's climate, insulation specifications must accommodate outdoor temperature variations from -25°C in winter to +30°C in summer months.

Heat Treatment and Pasteurisation Equipment

Pasteurisation remains the cornerstone of dairy food safety, and equipment design in this area demands precision engineering. The most common systems include:

• High-Temperature Short-Time (HTST) pasteurisers: Operating at 72°C for 15 seconds, these systems require precise temperature control within ±0.5°C

• Ultra-High Temperature (UHT) systems: Processing at 135-150°C for 2-5 seconds for extended shelf-life products

• Batch pasteurisers: Heating to 63°C for 30 minutes, often preferred by artisanal cheese makers in the Maritime provinces

Plate heat exchangers form the heart of most pasteurisation systems, with engineering specifications requiring careful calculation of heat transfer coefficients, typically ranging from 3,000 to 6,000 W/m²K depending on product viscosity. The regeneration section design is particularly important for energy efficiency, with modern systems achieving 90-95% heat recovery—a critical consideration given Atlantic Canada's energy costs.

Separation and Standardisation Technology

The separation of cream from skim milk and subsequent standardisation to achieve target fat percentages requires sophisticated centrifugal equipment. Modern separators operate at speeds between 4,000-7,000 RPM, generating centrifugal forces exceeding 6,000 g to efficiently separate fat globules from the aqueous phase.

Engineering Considerations for Separators

Designing separator installations involves numerous technical factors that professional engineers must address:

• Foundation design to accommodate dynamic loads and vibration isolation, typically requiring concrete pads with mass ratios of 3:1 relative to equipment weight

• Electrical supply specifications, with large separators requiring 30-75 kW three-phase power at 575V (Canadian industrial standard)

• Discharge system design for continuous or intermittent solids ejection

• Integration with inline fat standardisation systems using density meters and automatic cream dosing valves

• CIP circuit design ensuring complete coverage of all product-contact surfaces

For Maritime dairy processors handling products like Nova Scotia's renowned premium ice cream base, separator design must accommodate higher fat content streams while maintaining separation efficiency above 98%. This requires careful bowl geometry selection and feed rate optimisation.

Homogenisation Systems

Homogenisation prevents cream separation in fluid milk products by reducing fat globule size from approximately 3-4 microns to less than 1 micron. High-pressure homogenisers operate at pressures between 150-250 bar for single-stage units and up to 400 bar for two-stage systems used in specialty applications.

Engineering design for homogeniser installations must address:

• Pump selection and positive displacement capacity matching facility throughput requirements

• Valve and seat material specifications (typically tungsten carbide or ceramic) for wear resistance

• Pressure relief and safety interlock systems compliant with ASME and CSA standards

• Acoustic enclosures for noise reduction, as homogenisers can generate sound levels exceeding 85 dBA

Clean-in-Place (CIP) System Design

Sanitation is paramount in dairy processing, and CIP systems represent a critical engineering challenge that directly impacts product safety, operational efficiency, and environmental compliance. A well-designed CIP system can reduce cleaning time by 40-60% compared to manual methods while ensuring consistent sanitisation results.

CIP Circuit Engineering

Professional engineering of CIP systems requires detailed analysis of cleaning requirements for each circuit. Key parameters include:

• Flow velocity: Minimum 1.5 m/s in pipes, though 2.0-2.5 m/s is preferred for removing stubborn dairy soils

• Temperature: Caustic wash cycles typically at 75-85°C, acid rinses at 60-70°C

• Chemical concentration: Sodium hydroxide at 1.5-2.5% for protein removal, nitric or phosphoric acid at 0.5-1.0% for mineral deposits

• Contact time: Minimum 10-15 minutes per cleaning phase, with total cycle times of 45-90 minutes

Tank sizing calculations must account for the largest circuit volume plus adequate margin for concentration maintenance. In Atlantic Canadian facilities, engineers must also consider water source quality and treatment requirements, as well as wastewater discharge limitations that vary by municipality across Nova Scotia, New Brunswick, and Prince Edward Island.

Environmental and Sustainability Considerations

Modern CIP system design increasingly focuses on resource conservation. Engineering solutions include heat recovery from final rinse water, chemical recovery and reconcentration systems, and water recycling where regulations permit. A properly engineered CIP system can reduce water consumption by 30-50% compared to older designs—an important consideration for Maritime processors facing increasing water management requirements.

Process Piping and Instrumentation

The design of sanitary piping systems forms the backbone of any dairy processing facility. Engineers must specify materials, dimensions, and installation methods that meet both hygienic requirements and operational demands.

Material Specifications and Standards

Dairy processing piping typically utilises 304 or 316L stainless steel, with the latter preferred for applications involving high chloride environments or aggressive cleaning chemicals. Key specifications include:

• Surface finish of Ra ≤ 0.8 μm (32 microinch) for product-contact surfaces, with Ra ≤ 0.4 μm for critical applications

• Orbital welding with autogenous (no filler) welds and interior purging to prevent oxidation

• 3-A Sanitary Standards compliance for all fittings, valves, and components

• Slope requirements of minimum 1:100 for self-draining configurations

Piping layout design must balance sanitary requirements with practical considerations such as accessibility for maintenance, thermal expansion accommodation, and support spacing that prevents sagging while allowing for CIP drainage.

Instrumentation and Control Systems

Process control in modern dairy facilities relies on sophisticated instrumentation networked through PLC (Programmable Logic Controller) or DCS (Distributed Control System) architectures. Essential instrumentation includes:

• Sanitary pressure transmitters with flush-mount diaphragms and 4-20mA output signals

• Temperature sensors (RTDs or thermocouples) with sanitary housings and response times under 3 seconds

• Electromagnetic flow metres for conductive dairy products, with accuracy specifications of ±0.2-0.5%

• Level measurement using radar, guided wave radar, or hydrostatic pressure for tanks

• Turbidity sensors for CIP phase change detection and product recovery optimisation

Control system design must incorporate safety interlocks, batch recording for regulatory compliance, and integration capabilities with plant-wide SCADA systems. Engineers must also address cybersecurity considerations, as these systems increasingly connect to corporate networks and remote monitoring platforms.

Specialised Processing Equipment for Value-Added Products

Atlantic Canada's dairy industry has seen significant growth in value-added products, including artisanal cheeses, premium yogourts, and specialty ice creams. Engineering support for these applications requires understanding of unique processing requirements.

Cheese Making Equipment

Cheese production facilities in the Maritimes range from small farmstead operations producing under 1,000 kg per week to commercial facilities processing 50,000 litres or more daily. Equipment design considerations include:

• Cheese vats with precise temperature control (±0.5°C) and programmable agitation patterns

• Curd handling systems including mills, salting equipment, and pressing stations

• Brine tank circulation and temperature control systems maintaining 18-22% salt concentration at 10-14°C

• Aging room environmental control with humidity regulation between 80-95% RH

Cultured Products and Fermentation

Yogourt and cultured dairy products require incubation vessels with jacketed heating and cooling capabilities, precise temperature control during the 4-8 hour fermentation period, and gentle product handling to preserve texture. Engineering specifications must address aseptic design for extended shelf-life products and rapid cooling capability to halt fermentation at the optimal acidity level (typically pH 4.2-4.6).

Regulatory Compliance and Documentation

Dairy processing equipment design in Canada must satisfy multiple regulatory requirements, including CFIA food safety regulations, provincial dairy codes, and various industry standards. Professional engineering services ensure that equipment designs meet these requirements while remaining practical and cost-effective.

Key documentation requirements include:

• P&ID (Piping and Instrumentation Diagrams) sealed by a licenced professional engineer

• Equipment specifications and data sheets

• Hazard analysis documentation (HACCP prerequisite programs)

• Structural calculations for equipment supports and platforms

• Electrical load analyses and single-line diagrams

• Commissioning and validation protocols

Working with a professional engineering firm familiar with both Canadian regulations and the practical realities of Maritime dairy operations ensures that projects proceed smoothly from concept through commissioning.

Partner with Experienced Dairy Processing Engineers

The successful design and implementation of dairy processing equipment requires a comprehensive understanding of food science, mechanical systems, regulatory requirements, and regional operational conditions. Whether you are planning a new facility, expanding existing capacity, or upgrading aging equipment, professional engineering support is essential for achieving your operational and food safety objectives.

Sangster Engineering Ltd. provides comprehensive engineering services to dairy processors throughout Atlantic Canada, bringing decades of experience in process design, equipment specification, and project management. Our team understands the unique challenges facing Maritime dairy operations, from seasonal production variations to the specific requirements of regional regulatory authorities.

Contact Sangster Engineering Ltd. in Amherst, Nova Scotia to discuss your dairy processing equipment design needs. From initial feasibility studies through detailed design, construction support, and commissioning assistance, we deliver engineering solutions that help your operation achieve efficiency, compliance, and product quality goals. Let our expertise support your success in Atlantic Canada's dynamic dairy industry.

Partner with Sangster Engineering

At Sangster Engineering Ltd. in Amherst, Nova Scotia, we bring decades of engineering experience to every project. Serving clients across Atlantic Canada and beyond.

Contact us today to discuss your engineering needs.