Principles and Objectives

1. Design Principles

Safe and reliable: Strictly enforce mandatory provisions to ensure the safety of personnel, equipment, and goods

Energy saving and environmental protection: Select high-efficiency and energy-saving equipment to reduce operating energy consumption and meet environmental protection requirements

Economically reasonable: Control construction investment and operating costs while meeting functional requirements

Advanced technology: adopting mature and reliable technical solutions to ensure stable operation of the system

Convenient operation: Optimize the operation process for easy daily maintenance and management

2. Design Objective

Storage temperature control accuracy: ± 1 ℃ (refrigerated room), ± 1.5 ℃ (frozen room)

Annual operating energy consumption index: in line with national energy-saving standards

System reliability: Annual failure rate ≤ 1%

Automation level: achieve remote monitoring and automatic control

Architecture and Structural Design

1. Site Selection and Overall Layout of the Warehouse

Site selection requirements: Convenient transportation, flat terrain, far from pollution sources, meeting fire safety distance requirements (distance from civil buildings ≥ 60m, ammonia refrigeration system ≥ 150m)

General layout: Clear functional zoning, reasonable logistics flow, and the establishment of a circular fire lane (width ≥ 4m)

Fire separation distance: fire resistance rating not lower than level 2

2. Warehouse Layout

Functional zoning: Divide refrigeration rooms, freezing rooms, corridors, platforms, and other areas according to storage requirements

Fire compartments: Divided according to Table 4.2.2, each fire compartment area shall not exceed the standard limit

Emergency exit: Cold storage rooms with a building area greater than 1000 square meters must have at least 2 cold storage doors, and the evacuation distance must meet the requirements

Floor height design: Determine the net height based on the stacking height of goods and the arrangement of shelves, generally not less than 4.5m

3. Thermal Insulation Design

Enclosure structure: Polyurethane sandwich panels or on-site sprayed polyurethane are used, and the thickness is determined according to the storage temperature (-18 ℃ storage temperature is recommended to be ≥ 150mm)

Thermal insulation material: thermal conductivity ≤ 0.024W/(m · K), combustion performance B1 level

Hot bridge treatment: Special sealant is used to seal the board joints, through wall holes, and other parts

Airtightness requirement: air leakage rate ≤ 1.5%

4. Moisture and Vapor Barrier Design

Moisture proof layer setting: A moisture-proof vapor barrier layer is set up on the high temperature side, using PE film or aluminum foil composite film

Continuity of vapor barrier: overlap width ≥ 100mm, sealing treatment at joints

Ground moisture-proof: A moisture-proof layer is installed above and below the ground insulation layer to prevent the floor from freezing and swelling

5. Key Points of Structural Design

Structural form: reinforced concrete frame structure or steel structure

Load value: Consider cargo stacking load, equipment load, etc

Temperature stress: Considering the effect of cooling shrinkage, set temperature steel bars (reinforcement ratio ≥ 0.3%)

Foundation burial depth: The burial depth of the wall column foundation should not be less than 1.5m from the outdoor floor downwards

Refrigeration System

1. Design Parameters

Storage temperature requirements: determined based on the stored goods (e.g. freezing room -25 ℃~-18 ℃, refrigeration room -18 ℃~0 ℃)

Relative humidity: 15% to 95% (adjusted according to the requirements of the goods)

Refrigerant selection: R404A, R507, R134a (to be determined according to scale and safety requirements)

System form: direct expansion or indirect refrigeration system

2. Load Calculation

Calculate the load according to Section 6.2 of the standard, including:

Thermal flow rate of enclosure structure: Q ₁=K · F ·Δ t

Freight heat flow rate: Q ₂=G · (h ₁ - h ₂)/τ

Ventilation and air exchange heat flow rate: Q ∝=n · V ·ρ·Δ h/24

Motor operation heat flow rate: Q ₄=1000 ·∑ N ·ξ

Operating heat flow rate: Q ₅=q · F

Mechanical load: Qj=(n ₁ Q ₁+n ₂ Q ₂+n ∝ Q ∝+n ₄ Q ₄+n ₅ Q ₅) · R

3. Equipment Selection

Compressor: Select based on evaporation temperature, condensation temperature, and cooling capacity, and consider backup units

Condenser: air-cooled or water-cooled, depending on environmental conditions

Evaporator: air cooler or exhaust pipe, selected according to the storage temperature and cargo characteristics

Auxiliary equipment: oil separator, accumulator, gas-liquid separator, intercooler, etc

Energy efficiency requirement: COP ≥ 3.0 (according to standard requirements)

4. System Configuration

System partitioning: independent or parallel systems in different temperature zones

Defrosting methods: electric defrosting, water defrosting, or hot air defrosting

Control mode: automatic control, set temperature, pressure, and liquid level protection

5. Pipeline Design

Pipe selection: seamless steel pipe or copper pipe, material meets standard requirements

Pipeline layout: Slope and spacing between supports and hangers comply with the provisions of Section 6.5 of the standard

Pipeline insulation: The thickness of the insulation layer is calculated based on the economic thickness, and a moisture-proof layer is installed externally

Pipeline identification: Color identification based on medium and flow direction

6. Security and Monitoring

Safety devices: high pressure, low pressure, oil pressure, exhaust temperature protection

Leakage detection: refrigerant leakage alarm system, automatic alarm when the concentration reaches the set value

Emergency stop: Set manual emergency stop button

Monitoring system: real-time monitoring of temperature, pressure, liquid level, and operating status

Electrical System Design

1. Power Supply and Distribution System

Load level: Level 2 load (important equipment), Level 3 load (general equipment)

Power requirements: dual circuit power supply or backup generator set up

Distribution mode: radial or trunk type, independent circuit for important equipment

Reactive power compensation: power factor compensation to 0.9 or above

2. Refrigeration Room Electrical

Equipment distribution: Independent control of equipment such as compressors, water pumps, fans, etc

Lighting system: Explosion proof lamps, illumination ≥ 150lx

Grounding protection: TN-S system, repeated grounding

Lightning protection measures: Three types of lightning protection buildings are equipped with lightning arresters, down conductors, and grounding devices

3. Warehouse Electrical

Lighting requirements: Cold room illumination ≥ 50lx, hallway illumination ≥ 100lx

Socket setting: maintenance socket, moisture-proof type

Line laying: exposed or concealed installation through pipes, and anti cold bridge treatment should be applied to the insulation layer where it passes through

Emergency lighting: Install emergency lighting and evacuation instructions in important areas

4. Automatic Control System

Control mode: PLC or DCS system, achieving automatic control

Detection parameters: temperature, humidity, pressure, liquid level, operating status

Alarm function: Over limit alarm, fault alarm, SMS notification

Data recording: historical data storage, traceable query

Water Supply, Drainage and Fire Protection Design

1. Water Supply System

Water usage points: cooling water and defrosting in the refrigeration room

Water quality requirements: meet equipment requirements, and install water treatment devices if necessary

Water supply pressure: meet the water requirements at the most unfavorable point

2. Drainage System

Drainage method: gravity flow or pressure flow

Drainage points: cooling fan water tray, defrosting water, floor flushing water

Drainage slope: ≥ 1%, set up water seal or water seal well

Antifreeze measures: Insulation or electric tracing of drainage pipes in cold regions

3. Fire Protection System

Fire water source: municipal fire water supply or fire water pool

Fire hydrant system: Indoor and outdoor fire hydrants, set according to specifications

Automatic sprinkler: Automatic sprinkler is installed in elevated cold storage or cold storage with an area greater than 1500 square meters

Fire extinguisher configuration: configured according to severe hazard level, type determined by refrigerant

HVAC and Ground Antifreeze

1. Heating and Air Conditioning

Heating method: radiator heating or hot air heating

Air conditioning system: Air conditioning is installed in the refrigeration room and control room

Temperature requirement: The refrigeration room should be at least 10 ℃ in winter, and the control room should be between 18-26 ℃

2. Ventilation System

Mechanical ventilation: Install mechanical ventilation in areas such as hallways and platforms

Ventilation rate: calculated according to standards

3. Ground Antifreeze

Antifreezing methods: natural ventilation, mechanical ventilation, or heating antifreeze

Heating load: calculated according to specifications

Ventilation rate: calculated according to the standard formula

Construction requirements: Ground insulation layer, moisture-proof layer, heating pipe or ventilation duct

Energy Saving and Environmental Protection Measures

1. Energy Saving Measures

Equipment selection: Select high-efficiency compressors, fans, and water pumps with energy efficiency levels not lower than level 2

System optimization: frequency conversion control, hot air defrosting recovery, heat recovery utilization

Insulation optimization: Optimize insulation thickness to reduce cooling loss

Energy saving lighting: LED lighting, intelligent control

2. Environmental Protection Measures

Refrigerant: Choose environmentally friendly refrigerant with ODP=0 and low GWP value

Noise control: equipment vibration reduction, sound insulation treatment, factory boundary noise meets standards

Wastewater treatment: defrosting water, cooling water recycling or standard discharge

Waste: professional recycling and treatment of waste oil and waste refrigerant

Safety Measures

1. Structural Safety

The seismic fortification intensity shall be determined according to local requirements

Structural safety level 2, service life of 50 years

Fire compartments and evacuation routes comply with regulations

2. Equipment Safety

Pressure vessels and pressure pipelines are managed as special equipment

Regular calibration of safety valves and pressure gauges

Explosion proof, moisture-proof, and corrosion-resistant electrical equipment

3. Safe Operation

Improvement of operating procedures and emergency plans

Personnel training and certification for employment

Regular inspection and maintenance

4. Emergency Measures

Emergency Response Plan for Refrigerant Leakage

Fire alarm and extinguishing system

Emergency evacuation routes and signage