While routine management of grain silos is relatively less demanding during the cold winter months, maintenance and upkeep are significantly more crucial. This is primarily due to the harsh winter weather, which increases the risk of major accidents from unforeseen events such as strong winds, blizzards, and extremely low temperatures. These natural disasters pose a significant challenge to the quality of grain steel silo. Within our group, we will explain the basic operational procedures for grain silos during winter.
The following are the basic operational procedures for grain silos during winter, which can be divided into four parts: core management principles, daily operation and inspection, inbound and outbound management, and emergency plans.
1. Core Management Principles: Windproofing, Waterproofing, and Condensation Prevention
The core of winter management is controlling the temperature and humidity inside the grain pile to prevent condensation, mold, and crusting.
1.1. Temperature Control is Key:
- Objective: To maintain a stable and uniform temperature inside the grain pile as much as possible, minimizing the temperature difference between the inside and outside of the grain pile, and between the upper and lower layers of the grain pile.
- Principle: When hot air encounters a cold grain surface or storage wall, it cools below the dew point, forming condensation. This leads to increased local moisture and mold growth.
1.2. Humidity Control is Fundamental:
- Objective: Control the humidity inside the storage area to prevent the intake of cold, humid air from the outside.
- Principle: High humidity creates a breeding ground for mold and directly increases grain moisture content.
2. Daily Operation and Inspection Points
2.1. Grain Condition Monitoring System
- High-Frequency Monitoring: Increase the frequency of grain condition monitoring in winter. A comprehensive monitoring at least once a week is recommended, with more frequent monitoring before and after sudden temperature changes or rain/snow.
- Temperature Difference Between Layers: Pay close attention to the temperature difference between different layers within the grain pile, especially the difference between the upper and lower layers. If the temperature difference exceeds 5°C~7°C, there is a risk of condensation.
- Upper Layer Temperature: The temperature of the storage space and the surface of the grain pile is most susceptible to external influences and should be closely monitored.
- Temperature near the wall: Steel silos have high thermal conductivity, and the temperature of grain near the silo wall is easily affected by low external temperatures.
2.2. Mechanical Ventilation Management
- Principle: "Slow, even, and selective."
- Blind ventilation is prohibited: Ventilation is absolutely prohibited on rainy, snowy, foggy days, or when the external relative humidity is higher than 75%, otherwise a large amount of moisture will be brought into the silo.
- Ventilation and cooling: Ventilation should be carried out on cold, dry, sunny days (usually in the afternoon) to use dry, cold air to lower the grain temperature and reduce the temperature difference between inside and outside.
- Ventilation and Conditioning: If the purpose is only to reduce local hot spots, micro-ventilation should be used, or ventilation should be carried out when the diurnal temperature range is small.
- Ventilation method: Intermittent ventilation is preferred, i.e., ventilating for a period of time and stopping for a period of time to allow the temperature and humidity inside the grain pile to reach equilibrium, avoiding rapid cooling and heating.
2.3. Silo and Equipment Maintenance
Sealing Inspection:
- Conduct a thorough inspection of all joints and gaps in the silo roof, walls, manholes, and vents to prevent the infiltration of wind, snow, and rainwater.
- Ensure the sealing rings at temperature measuring cables and ventilation ducts are intact.
Anti-condensation Inspection:
- Regularly check the inside of the silo roof and walls for condensation. If present, this indicates insufficient insulation or a large temperature difference between the inside and outside, requiring increased ventilation or other measures.
Equipment Antifreeze:
- Inspect the bearings and lubricating oil of outdoor equipment such as fans, conveying equipment, and motors. Replace antifreeze lubricating oil if necessary.
- For water pumps, pipes, and other piping equipment that have not been used for a long time, drain any remaining water to prevent freezing and cracking.
Snow Removal and De-icing:
- Promptly remove snow from the silo roof and surrounding platforms to reduce structural load and prevent meltwater leakage.
- Remove icicles from ladders, railings, etc., to prevent falls and injuries.
3. Warehouse Management
3.1. Warehousing Operations
- Grain Quality: Strictly control the moisture and impurities of grain entering the warehouse. The moisture content of grain entering the warehouse in winter should be lower than the summer standard, ideally not exceeding 1%-2% of the safe moisture level.
- Grain Temperature: Avoid directly storing "hot grain." Newly harvested or dried grain must be cooled to near ambient temperature before being stored; otherwise, strong heat convection will form inside the warehouse, leading to severe condensation.
- Storage Method: If conditions permit, separate storage can be used to store grains with different temperatures and humidity levels.
3.2. Outbound Operations
- Safety First: Inspect the work area, remove ice and snow, and ensure that the road surface and work platform are non-slip.
- Even Grain Removal: Use a balanced outbound method to avoid creating steep slopes, otherwise condensation will easily occur due to temperature differences at the slopes.
- Preventing Blockages: Low temperatures may cause grain (especially grain with slightly higher moisture content) to freeze at the bottom discharge port of the warehouse, causing difficulties in discharging. If necessary, the bottom ventilation system can be activated for short-term preheating before unloading.
4. Common Problems and Emergency Plans
4.1. Condensation/Coverage on the Grain Pile Surface:
- Immediate Action: Immediately stop all operations that may introduce moisture.
- Local Treatment: Implement localized mechanical ventilation in the condensation area, or use the silo's dedicated turning equipment to agitate the surface and dissipate moisture and heat.
- General Ventilation: If conditions are suitable (cold, dry outside air), immediately activate the ventilation system for cooling and dehumidification.
4.2. Power Outage:
- Start the backup power supply (if available), prioritizing the operation of the grain condition monitoring system and necessary ventilation systems.
- If there is no backup power supply, manual inspections should be intensified, using touch, smell, etc., to assist in assessing the grain condition.
4.3. Equipment Frozen:
- Do not force restart. Use safe methods such as hot air guns or steam to slowly thaw the equipment.
5. Precautions
5.1. Personnel Safety
- Wear non-slip shoes, cold-weather clothing, and safety helmets. Wear insulated gloves when handling metal equipment to avoid frostbite or electric shock.
- Before working on the warehouse roof, ladders, or platforms, thoroughly clear away accumulated snow and ice. Lay non-slip mats if necessary. Single-person work at heights is prohibited.
- When entering the warehouse for inspection or work, ventilate first. Assign a dedicated person to monitor from outside, carrying a portable gas detector to prevent oxygen deficiency or the accumulation of harmful gases.
5.2. Safe Equipment Operation
- Before starting ventilation fans, conveyors, and other equipment, conduct a no-load test run to check if transmission components are stuck or frozen due to low temperatures. Forced starting is prohibited.
- The insulation of electrical equipment (switches, cables, motors) must be checked regularly. Low temperatures can easily cause wiring to become brittle, preventing short circuits and fires. Disconnect the power supply after equipment is stopped.
- During grain conveying and unloading, monitor the material condition. Grain is prone to clumping in winter; prevent equipment blockage that could lead to overload or mechanical failure.
5.3. Work Environment and Structural Safety
- Daily clear snow and ice from the surrounding passageways to keep the work area clear and dry. Post "Caution: Slippery Floor" warning signs.
- Regularly inspect the steel structure of the warehouse, focusing on welds and supporting components. Low temperatures increase the brittleness of steel; avoid impacts that could cause cracking and collapse.
- Control the time spent working inside the warehouse. Avoid prolonged outdoor work in extremely cold environments to prevent frostbite. Provide first-aid supplies (hand warmers, first-aid kits).
5.4. Emergency Response Preparation
- Develop emergency plans for frostbite, slips, equipment freezing, and fires. Organize training and drills for workers, clarifying the response procedures.
- Ensure the work site is equipped with fire extinguishers, de-icing agents, first-aid kits, and other supplies for rapid access in low-temperature environments.
- If warehouse deformation, equipment malfunction, or personnel injury is discovered, immediately stop work, evacuate the site, and activate the emergency response. Do not attempt any unauthorized actions.
6. Summary: Key Points for Winter Steel Silo Operation
- Frequent Monitoring: Increase the frequency of grain condition monitoring, especially temperature and humidity.
- Tight Sealing: Ensure the silo is sealed tightly, protecting it from wind, snow, and rain.
- Caution with Ventilation: Ventilate only in dry, cold weather; high humidity ventilation is strictly prohibited.
- Keep Warm Grain Away: High-temperature grain must not be placed directly into the silo.
- Regular Inspections: Regularly check for condensation on the silo, equipment operation, and structural safety.
- Prompt Handling: If condensation, excessive heat, or other abnormalities are detected, take immediate and appropriate measures.
The above are the basic operational points for operating grain steel silo in winter. We hope this explanation will be helpful in your future winter operations. Following these basic points can effectively prevent and address various risks associated with winter grain storage in steel silos, ensuring the safe passage of stored grain through the cold winter. Shandong Xuelai Storage Co., Ltd. specializes in building large-scale steel grain silos and feed silos. Please feel free to contact us if you have any product needs.
Written by
Shandong Shelley Grain Steel Silo Co., Ltd
Editor Jin
WhatsApp : +86-18653877118
Email : shelley@cnshelley.com
