11,000㎡ Multi-Temperature Agricultural Cold Storage Logistics Park Project | Pingxiang, Jiangxi

Author: Chen Hao, Senior Cold Storage Design Engineer
13 years of large-scale multi-story cold storage EPC design experience, specialized in agricultural wholesale market cold chain park construction. Completed over 20 multi-temperature layered cold storage projects across southern China, member of China Cold Chain Logistics Association.

Table of Contents

1. Project Background & Client Demand
2. Overall Layout & Floor Division Logic
3. Full Temperature Zone Technical Parameters
4. Customized Insulation & Vapor Barrier Design
5. Refrigeration Unit Matching & System Configuration
6. Intelligent Control & Energy-Saving Design Highlights
7. Classified Agri-Product Storage Standard Matching
8. Key Construction Difficulties & Custom Solutions
9. Post-Operation Data & Customer Benefit Analysis
10. FAQ for Large Agricultural Cold Park Investors

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1. Project Background & Client Demand

Basic Project Info

• Client: China Agricultural Wholesale Market Holding Co. (State-owned national agricultural logistics platform)
• Location: Pingxiang City, Jiangxi Province (subtropical high temperature & high humidity climate)
• Total building area: 11,000 ㎡ three-story integrated cold storage logistics park

Handover completion: May 2020, full EPC turnkey delivery by Haocool Refrigeration

Core Client Pain Points Before Construction

1. Local fresh produce circulation lacked centralized multi-temperature distribution hub; leafy greens, fruits, frozen seafood suffered high post-harvest loss without standardized cold chain;
2. Single-temperature small cold rooms could not realize mixed storage of refrigerated fresh goods, frozen aquatic products and semi-finished agricultural food;
3. Traditional cold houses had high power consumption, unstable temperature fluctuation, and no automatic monitoring traceability system to meet wholesale market regulatory requirements.

Project Core Design Target

Build a three-layer vertically distributed multi-temperature cold storage, covering 0–4°C chilling, adjustable variable temperature zone and -23°C deep freezing; realize integrated receiving, storage, sorting and delivery for regional agricultural wholesale market, reduce overall commodity spoilage loss below 4%.

2. Overall Layout & Floor Division Logic

Total construction area split into three independent cold zones with separated refrigeration circuits, independent air circulation and isolated cargo passages to avoid cold loss during loading/unloading:

Floor	Functional Positioning	Usable Area	Core Operation Scenario
1F Perishable Chilling Zone	Fresh leaf vegetables, berries, fruits, pre-cooling temporary storage	3,700 ㎡	Daily wholesale short-cycle fresh goods turnover
2F Convertible Variable Temp Zone	Root vegetables, preserved agricultural products, semi-finished food	3,700 ㎡	Adjustable 4℃ ~ -10℃ according to seasonal supply
3F Deep Frozen Storage Zone	Frozen seafood, frozen meat, quick-frozen agricultural products	3,600 ㎡	Long-term stockpile for off-season supply
Supporting auxiliary facilities: 6 loading & unloading docks, buffer air curtain rooms, central intelligent monitoring control room, spare machine room, drainage and defrost recovery system.

 

3. Full Temperature Zone Technical Parameters

Comply with national standard GB 50072-2023 Cold Storage Design Specification and ASHRAE fresh produce storage standards:

Floor	Temperature Range	Allowed Temp Deviation	Core Supporting Technology
1F Chilling Zone	0–4℃	±0.5℃	Double-layer cyanate ester vapor barrier + low-speed humidifying air coolers
2F Variable Temp Zone	-23℃ ~ 4℃	±0.8℃	Convertible independent chamber system, separate cold supply loop
3F Deep Freezing Zone	-23℃	±1℃	180mm thick sprayed PU insulation + liquid pump circulation cooling

4. Customized Insulation & Vapor Barrier Design

Jiangxi summer high humidity easily causes wall condensation and cold bridge penetration, so the project adopted graded insulation thickness differentiated by temperature zone:

Parameter	0–4°C Chilling Zone	-23°C Deep Freezing Zone	Industry Advantage
Sprayed PU Insulation Thickness	100mm	180mm	Thicker frozen layer avoids floor cold bridge frost buildup
Vapor Barrier Structure	Double-layer cyanate ester composite film	Double-layer cyanate ester composite film	Block southern humid air penetration, reduce insulation aging
Fire Classification Standard	Euroclass E (equivalent to domestic B2 flame retardant)	Euroclass E	Meet agricultural market fire acceptance standards
Key optimization: All floor slab joints, column wall connections filled with closed-cell PU foam to eliminate cold bridge leakage points unique to multi-story cold buildings.

5. Refrigeration Unit Matching & System Configuration

All semi-hermetic screw compressors matched according to peak summer cooling load of Pingxiang local 36℃ ambient temperature:

Equipment Model & Spec	Quantity	Matching Zone	Design Advantage
81kW (110HP) Semi-Hermetic Screw Compressor	4 sets	1F & 2F chilling/variable temp area	Variable frequency load adjustment for fluctuating daily cargo volume
55kW (75HP) Semi-Hermetic Screw Compressor	4 sets	3F deep frozen zone	Stable low-temperature continuous operation
Hot Gas Defrost Ceiling Air Coolers	32 units	All three floors	Avoid electric defrost high power waste
Liquid Pump Circulation Refrigeration System	2 sets	-23°C frozen floor	Improve heat exchange efficiency by 18% vs gravity liquid supply

6. Intelligent Control & Energy-Saving Design Highlights

6.1 Hierarchical Independent Humidity Control

• 1F & 2F: Independent humidifier modules, stable RH 85%–95% for fresh vegetable anti-wilting storage
• 3F Deep freeze floor: Low humidity automatic cycle ventilation, prevent frost accumulation on goods surface

6.2 Core Energy-Saving Indicators

1. Full-load COP reaches 3.8 at -23℃ freezing condition, 25% higher than conventional fixed-speed unit baseline (ASHRAE test standard);
2. Heat recovery defrost system: Recycle compressor waste heat for chamber defrost, cut defrost power consumption by over 30%;
3. Cloud-based load intelligent scheduling: Automatically reduce unit running power during low night electricity price valley period.

6.3 Full Traceability Monitoring System

24-hour real-time temperature & humidity sensor coverage, remote mobile phone alarm, all storage data permanently stored to meet agricultural market supervision and food safety traceability requirements.

7. Classified Agri-Product Storage Standard Matching

Customized storage schemes designed targeting the wholesale market’s mainstream agricultural goods, matched to three temperature zones:

Product Category	Storage Temp	RH Level	Usable Storage Cycle	Matching Floor
Leafy Greens (Cabbage, Spinach)	1℃	95%	Up to 21 days	1F Chilling Zone
Root Vegetables (Potato, Radish)	4℃	90%	Up to 180 days	2F Variable Temp Zone
Frozen Seafood & Frozen Meat	-23℃	Dry low humidity	Up to 18 months	3F Deep Freeze Zone

8. Key Construction Difficulties & Custom Solutions

Difficulty 1 Multi-story cold slab anti-cold-bridge construction

Ordinary single-layer cold storage does not involve floor heat loss; three-story vertical structure easily forms vertical cold bridges.
Solution: Separated sprayed PU insulation between upper and lower floors, waterproof anti-freeze floor coating, drainage slope design for defrost water centralized collection.

Difficulty 2 Southern high humidity vapor barrier failure risk

Long rainy season in Pingxiang leads to wall internal condensation.
Solution Full wall double-layer cyanate ester vapor barrier with lap joint sealing process, strict air tightness pressure test before equipment commissioning.

Difficulty 3 Synchronized commissioning of multi-temperature independent circuits

Three floors with different cooling demands are easy to cause system pressure imbalance.
Solution Separate refrigeration host loops for each floor, independent PLC control logic, staged temperature drop debugging during handover.

9. Post-Operation Data & Customer Benefit Analysis

After 5 full years of stable operation starting 2020:
1. Post-harvest spoilage loss of local agricultural products reduced from original 16% down to 3.8%;
2. Comprehensive power consumption per ton of goods reduced by 22% compared to the client’s previous scattered small cold rooms;
3. Realize off-season stockpile sales of frozen aquatic products, average annual gross profit increase of the wholesale market platform over USD 110,000 via seasonal price difference;
4. Realize centralized unified cold chain distribution for surrounding 12 counties, forming regional agricultural circulation core competitiveness.

10. FAQ for Large Agricultural Cold Park Investors

Q1 What’s the core difference between single-layer cold storage and multi-story agricultural logistics cold park?

A Multi-story projects save land resources for urban wholesale markets; each floor can be divided into independent temperature zones, but higher requirements for floor insulation, cold bridge treatment and layered refrigeration loop design, single-layer warehouses have simpler construction and lower technical difficulty.

Q2 Is COP 3.8 a reliable energy-saving index for -23℃ deep freezing?

A The data is tested under standard ASHRAE working conditions (ambient 32℃, full warehouse load). Variable frequency screw unit + liquid pump circulation system jointly realize high efficiency, traditional fixed-speed units only reach COP around 3.0 under the same condition.

Q3 How to solve condensation problem for cold storage in southern high-humidity areas like Jiangxi?

A Adopt double-layer composite vapor barrier sprayed PU wall insulation, set air curtain buffer rooms at all loading doors, match automatic humidity adjustment equipment for fresh storage floors.

Q4 What supporting facilities must be equipped for agricultural wholesale market cold parks?

A Multi-temperature layered zoning, independent pre-cooling temporary storage area, loading & unloading buffer docks, cloud temperature traceability system, heat recovery defrost energy-saving module, centralized defrost drainage system.

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If you plan to invest or design multi-temperature layered agricultural cold storage logistics parks in southern high-humidity regions, contact our EPC engineering team for site survey, customized layout drawing and detailed turnkey budget quotation.

Construction & Completion Photos