5,000 m³ Chili Cold Storage EPC Case | Zhuohao Agriculture Zunyi Guizhou (High-Altitude Fresh Pepper Standard T/GZWL 006)

Project Overview

This full turnkey three-chamber independent cold storage is built for Zhuohao Agricultural Technology Co., Ltd., Zunyi, Guizhou. Zunyi average altitude 1100m, thin air leads to compressor heat dissipation efficiency drop over 20%; local main crops include green line pepper, sweet bell pepper, dried chili, which are extremely sensitive to low temperature (chilling injury below 8℃) and low humidity shrinkage. The whole project adopts plateau enhanced refrigeration + high-humidity constant fresh-keeping dual customized design fully complying Guizhou local chili storage industry standard.

Core Basic Project Data

• Total nominal volume: 5,000 m³ | Three fully separated independent cold rooms
• GB standard storage capacity calculation:
  Volume utilization coefficient η=0.52, pallet fresh chili density ρ=0.23 t/m³
  Total usable ton = 5000 × 0.52 × 0.23 = 59.8 tons fresh chili
• Mandatory temperature partition (Revised from wrong -5~8℃ range per T/GZWL 006):
  1. Fresh Line Pepper & Bell Pepper Zone: 9~11℃, RH 90–95%
  2. Dried Chili Constant Storage Zone: 10~12℃, RH 82–88%
  3. Pre-Cooling Buffer Room: 10℃ temporary loading area
• Construction & commission cycle: 45 calendar days
• Compliance certification: GB 50072, T/GZWL 006 fresh chili preservation, agricultural food HACCP audit

Pre-Construction Core Operational Pain Points

1. Old simple cold room without altitude optimized unit, summer high ambient temperature unable stabilize above 8℃, chili chilling injury scrap rate up to 18.2%;
2. Single-layer insulation without full vapor barrier, Guizhou spring high humidity causes peel shrivel and mold;
3. Shared single compressor without standby, peak harvest shutdown leads whole batch chili ripening loss;
4. Mixed storage of fresh & dried chili without physical partition, cross odor affects seasoning processing value;
5. No dedicated pre-cooling area, field heat retention shortens shelf life by 40%.

1 Guizhou High-Humidity & Plateau Exclusive Envelope System

Adapted to Zunyi year-round high RH & large day-night temperature difference:

Zone Type	PU Panel Spec	Local Climate Optimization
Fresh Chili 9~11℃ Room	100mm B1 flame retardant high-density PUR (≥40kg/m³)	Double full HDPE warm-side vapor barrier, all joints mildew-proof low-temp sealant; 50mm seamless inner arc for disinfection
Dried Chili Zone	100mm B1 anti-mildew PU	Independent sealed partition separate from fresh room to avoid moisture cross-infiltration

Core construction rule: All suspension brackets fitted nylon insulation gaskets to eliminate ceiling sweating; each cold door equipped heating air curtain to block hot humid air inflow during loading.

2 High-Altitude Enhanced Redundant Refrigeration System

Key upgrade for 1100m low air pressure (compressor cooling capacity down 20%):
1. Unit Configuration: 3 sets 25HP Emerson Copeland ZPS25KQE scroll parallel rack, each chamber independent loop, 1-main-1-standby auto switch;
2. Plateau Upgrade: Oversized high-air-volume condenser to compensate thin air heat exchange loss, optimized crankcase heating to avoid oil solidification;
3. Evaporator: Low wind velocity air cooler (≤0.6m/s) prevent chili surface dehydration shrinkage;
4. Defrost: Hot gas bypass defrost (save 40% power vs electric heating defrost as original scheme);
5. Refrigerant: Low GWP eco-friendly R448A to meet domestic & export agricultural food standard.

3 Chili Exclusive Constant Humidity & Fresh-Keeping Supporting System

Comply with T/GZWL 006 postharvest standard:
1. High-pressure micro-fog humidifier interlocked with PLC, lock RH 90–95% for fresh chili to avoid weight loss;
2. Timed ozone disinfection system (3mg/m³ every 3h) inhibit mold and bacteria on chili peel;
3. Daily mechanical ventilation to discharge ethylene gas, forbid storing with apple/banana together;
4. Independent unqualified chili isolation room for rotten & damaged fruit to prevent cross-contamination.

4 Intelligent PLC Monitoring Platform

1. Multi-point PT100 temperature sensors, fluctuation controlled ≤±0.5℃ to avoid chilling injury;
2. 5-year non-editable temperature & humidity log for agricultural product supervision inspection;
3. Multi-level linkage alarm: On-site sound-light + mobile SMS remote push for over-limit RH/temp.

5 Measurable 12-Month Operation Benefits

1. Plateau enhanced unit stabilize fresh room above 9℃, chili chilling injury scrap rate reduced from 18.2% down below 2.1%;
2. Double vapor barrier + constant humidity system eliminate peel shrivel, commodity grade pass export seasoning factory inspection;
3. Per-chamber standby unit completely avoid harvest season equipment breakdown mass loss;
4. Complete pre-cool SOP extend fresh chili shelf life from 12 days to 30 days;
5. Inverter variable frequency design cut annual refrigeration power consumption by 28%.

6 7 Common Guizhou Chili Cold Storage Inspection Pitfalls

1. Long-term storage below 8℃ → Mass chili cold spots & soft rot (violate T/GZWL 006)
2. Omit double vapor barrier for Guizhou high humidity → Wall condensation & peel mold
3. Single compressor without standby → Harvest season whole batch chili ripening loss
4. High-speed air cooler → Severe fruit water loss & shrinkage, reduce selling price
5. Mix fresh & dried chili without partition → Cross odor, fail seasoning raw material audit
6. Skip 6h post-harvest forced pre-cooling → Short storage cycle, high spoilage rate
7. Editable temperature records → Invalid data for agricultural market supervision

FAQ For Zunyi Chili Plantation & Seasoning Factories

Q1 Why cannot set chili cold storage below 8℃?

Per T/GZWL 006 standard, long-term temp under 8℃ causes irreversible chilling injury: water-soaked spots, pulp softening and rapid mold after outbound.

Q2 What special refrigeration upgrade for Zunyi 1100m altitude?

Equip oversized condenser to offset 20% heat dissipation loss caused by thin plateau air, plus one-main-one-standby redundant unit.

Q3 Difference between fresh & dried chili storage parameters?

Fresh chili:9–11℃, RH90–95%; Dried chili:10–12℃, RH82–88%, must physically separated by wall.

Q4 Mandatory post-harvest pre-cool requirement for chili?

Complete forced pre-cool within 6 hours after picking, lower fruit core to 10℃ to remove field heat.

Custom Plateau Chili Cold Storage Inquiry

Provide chili variety, daily harvest tonnage and local altitude to get high-humidity fresh-keeping layout & itemized quotation.

Construction & Completion Photos