Low‑temperature circulating drying precise temperature control grain quality protection automatic shutdown

   The 5HH Batch Circulating Grain Dryer is a low‑temperature circulating grain drying equipment developed by Zhengzhou Wangu Machinery for large‑scale grain growers, family farms, grain cooperatives and small‑to‑medium grain‑oil processing plants. Designed for batch circulation drying of high‑moisture raw grain during harvest seasons, it can dehydrate corn, paddy rice, wheat, soybeans, sorghum, rapeseed and various grain‑oil seeds. Dried grain features stable moisture content and intact grains, meeting requirements for long‑term storage and further processing.

   Adopting a vertical tower structure, the unit integrates an elevating circulation system, drying sections, tempering sections and cooling units coordinated by an intelligent control system. It implements the low‑temperature drying process of drying‑tempering‑re‑circulation, which prevents rapid surface crusting of grains and hindered internal moisture migration. This greatly reduces grain cracking and breakage rates, making it suitable for both commercial grain and seed grain drying.

Grain is conveyed by the elevator to the top distributing mechanism for even grain spreading, then slowly descends through drying layers by gravity. Clean hot air penetrates the grain bed to remove moisture. After one drying cycle, grain is discharged from the bottom re‑circulating mechanism and lifted back to the tower top by the elevator for continuous circulation. Equipped with real‑time on‑line moisture monitoring, the dryer automatically terminates the drying process once grain moisture reaches the preset target, then proceeds to the cooling phase before final discharging. Compared with conventional simple drying equipment, this model delivers superior drying quality, lower energy consumption and higher automation.

Structural Composition

The circulating grain dryer consists of the following core components:
- Drying Bin: Made of galvanized steel plate with internal grain-bed ventilation layers for uniform hot-air distribution.
- Bucket Elevator: Lifts wet grain from the bin bottom to the top, completing the circulating transport.
- Top Distributor: Evenly disperses lifted grain back into the drying bin, preventing local accumulation.
- Hot-air Drying Section: Hot air passes through the grain bed for full contact heat and mass transfer.
- Temping & Cooling Section: Dried grain is tempered for moisture equalization, then cooled by ambient air to safe storage temperature.
- Exhaust System: Removes moisture-laden air from the bin, maintaining a dry drying environment.
- Heat Source System: 8 fuel options - natural gas, rice husk, biomass, heat pump, steam, coal, diesel, electric - flexibly configured to local conditions.
- Control System: Button or PLC control for automated drying, circulation, exhaust and cooling operation.

 Core Advantages

Main Features

• Low‑temperature Circulating Drying Process: Batch‑mode low‑temperature drying with sufficient tempering zones enables full internal‑external moisture equalization of grains. Risks of cracking and breakage are significantly mitigated, and seed germination rate is well‑preserved.

• Uniform & Stable Drying: Multi‑layer high‑efficiency angular box air distribution inside the tower ensures even hot‑air distribution without drying dead zones, achieving consistent moisture reduction across the whole grain batch.

• Intelligent Automatic Operation: Built‑in on‑line moisture detector and PLC touch‑screen control system support one‑touch automatic drying, intelligent hot‑air temperature adjustment, and automatic shutdown & discharging upon target moisture. Manual operation mode is also retained to accommodate different operator habits.

• Multi‑fuel Compatible Heat Source: Compatible with biomass hot‑blast stoves and coal‑fired hot‑blast stoves. Gas‑fired or oil‑fired heat exchangers are optional to cut operating costs according to local conditions.

• Heavy‑duty Industrial Construction: Main tower body is made of hot‑dip galvanized steel sheet for outstanding anti‑corrosion performance. Wear‑resistant components are adopted for elevators and grain discharging impellers to withstand heavy seasonal long‑hour operation.

• Flexible Site Adaptability: Compact vertical layout with small footprint. Installation is feasible both indoors in workshops and in open‑air yards. Multiple model specifications are available for applications ranging from small family farms to medium‑sized cooperatives.

• Easy Maintenance & Inspection: Multiple access doors and emergency grain discharge outlets are reserved for routine cleaning and fault troubleshooting. Smooth switching between different grain varieties minimizes cross‑contamination.

Application Fields

   This circulating grain dryer is widely used in family farms, grain‑planting cooperatives, township grain collection points, rice mills, flour mills, seed companies and oil‑processing enterprises. It processes corn, paddy rice, wheat, soybeans, sorghum, rapeseed, miscellaneous grains and various crop seeds.

Heat is supplied via indirect heat exchange. Clean hot air contacts grain directly, keeping smoke and dust out of grain piles for pure, contamination‑free dried products. Adjustable low‑temperature drying conditions handle both high‑moisture newly‑harvested damp grain and high‑standard seed grain for breeding. Grain is cooled in the cooling section after drying and can be directly put into warehouse for long‑term storage, effectively avoiding mildew and germination losses.

 Packaging & Quality Assurance

   Each circulating grain dryer is shipped in bare packing with core components well protected, meeting sea and land transport requirements. Standard packing is reinforced to prevent damage during loading and unloading; custom packing is also available. All equipment is produced under the ISO quality management system and tested before delivery. We provide a 12-month warranty covering the main frame and key components, together with online technical support, installation guidance and spare parts supply. Minimum trial order: 1 unit. Delivery time: 25-40 days. Payment: T/T advance or sight L/C. Please tell us your batch capacity, grain type and heat source preference, and we will recommend the most suitable model configuration with a competitive quote.