China Shandong Junxu Heavy Industry (Group) Co., Ltd. Company News

Working Principle and Core Characteristics of Wood Chip Rotary Dryer The wood chip rotary dryer is a key piece of equipment in industries such as wood processing, biomass pellet preparation, and edible mushroom substrate treatment. Its core function is to stably reduce the moisture content of wet wood chips (35%-60%) to the required 8%-15% through a continuous heat and mass exchange process. Its working mechanism is based on the synergistic effect of the equipment structure and thermal process, mainly encompassing four core aspects: heat source supply, material movement, gas-solid heat exchange, and intelligent control. Each aspect is precisely designed to form a closed-loop system. I. Core Working Principle 1. Heat Source System and Heat Medium Generation The equipment adopts a multi-source adaptable heat source design, compatible with various energy forms such as electric heating tubes, natural gas, coal, and biomass fuels (e.g., wood chip scraps). Heat energy is converted into a clean heat medium—drying hot air with a controllable temperature of 120℃-280℃—through a tubular heat exchanger, avoiding direct contact between fuel combustion products and materials, thus preventing contamination. Indirect heating models isolate the flame from the material through a heat exchanger, increasing heat utilization by over 20% compared to direct heating models; some high-end models can achieve a thermal efficiency of 80%. The heat source transmission pipeline is wrapped with insulation, controlling heat loss to within 5%, ensuring that heat energy is concentrated inside the drum. 2. Material Movement and Heat-Mass Exchange Process Wet sawdust is continuously fed into a rotary drum (typically 0.8-2.4 meters in diameter and 3-24 meters in length) installed at a 3°-5° angle by a screw feeder. The transmission system drives a gear ring via a motor and reducer, causing the drum to rotate smoothly at 3-15 rpm. Spiral lifting plates (lifting plates) distributed on the inner wall of the drum repeatedly lift and scatter the sawdust as the drum rotates, forming a uniform material curtain. This ensures that each sawdust particle has sufficient contact with the hot airflow, increasing the contact area by 4-6 times compared to static drying. Under the combined action of the lifting plates and the inclined angle of the drum, the material moves slowly along the drum wall in a spiral trajectory. The moving speed can be finely adjusted by the drum rotation speed to ensure that the material stays in the drum for 20-40 minutes, achieving gradient evaporation of moisture—first evaporating surface free water, then gradually removing internal bound water, ultimately controlling the moisture content fluctuation within ±1%. 3. Airflow Organization and Moisture Separation and Discharge High-temperature hot air, under the negative pressure of the induced draft fan, forms a counter-current or parallel flow with the material (counter-current flow is often used in biomass pellet production to improve thermal efficiency). The wet exhaust gas carrying water vapor enters the gas-solid separation system at the end of the drum. It first passes through a cyclone separator to remove more than 80% of large dust particles, and then is filtered by a bag filter, ensuring that the dust emission concentration is ≤10mg/m³, far below the national environmental protection standard of 30mg/m³. Some models are equipped with a finned waste heat recovery device, which can recover 30% of the heat energy in the exhaust gas for preheating cold air, further reducing unit energy consumption. 4. Intelligent Control and Process Stability Guarantee The equipment is equipped with a distributed sensor control system. Humidity and temperature sensors are installed at the feed inlet, the middle section of the drum, and the discharge outlet to collect real-time data on material moisture content and hot air temperature, transmitting this data to the PLC controller. The system automatically adjusts three core parameters using frequency conversion technology: the feed rate of the screw feeder (0.5-5t/h, depending on the model), the heating power of the hot air furnace, and the airflow of the induced draft fan. When the discharge moisture content is detected to be too high, the system will simultaneously reduce the feed speed and increase the hot air temperature to ensure that the final moisture content is accurately met, avoiding material quality fluctuations caused by manual adjustments. II. Core Product Characteristics - Strong Structural Adaptability: The drum is welded from thickened steel plates, with a roller ring-thrust support structure, capable of withstanding the impact of wet materials and preventing horizontal displacement during tilted operation. Its continuous operating life exceeds 8000 hours. The lifting plate angle is optimized for material particle size, adapting to different specifications of wood chips from 0.1-5mm, with no significant adhesion or accumulation. - Stable Drying Efficiency: Through optimized material curtain formation and airflow design, the drying intensity per unit volume reaches 20-35 kg/(m³·h), and the energy consumption per ton is controlled at 120-180 kWh when the moisture content is reduced from 50% to 12%, with a moisture content deviation of ≤1% between different batches. - High Operational Safety: Addressing the flammable nature of wood chips, the system is equipped with explosion-proof doors, a nitrogen replacement system, and an oxygen concentration monitor. When the oxygen concentration inside the drum exceeds 5%, an automatic alarm is triggered, and inert gas protection is activated. The equipment's operating noise is ≤85 dB(A), meeting industrial noise standards. - Convenient Operation and Maintenance: Adopting a modular design, the hot air furnace and dust collector can be independently inspected and maintained. The drum interior has no dead corners and is equipped with an automatic vibration dust removal device, requiring only a full cleaning once a month. Routine maintenance only requires checking the transmission system lubrication level and sensor calibration. III. Core Advantages and Applications of Large-Scale Timber Drying Chambers Large-scale timber drying chambers, as crucial equipment in the timber drying field, complement wood chip drum dryers. They are particularly suitable for batch processing of block and board-type timber. Their core advantages are reflected in their technical characteristics, production efficiency, and environmental friendliness, as detailed below: 1. Core Technical Advantages - Energy-Saving and High-Efficiency Characteristics: Utilizing heat pump drying technology based on the reverse Carnot cycle principle, the core technology uses a small amount of electricity to drive the compressor, absorbing free heat from the air, saving over 60% more electricity than traditional electric heating equipment. The all-electric operation mode produces no combustion emissions, ensuring stable thermal efficiency and a coefficient of performance (COP) of 3-5, far exceeding that of traditional drying equipment. - Controllable Drying Quality: Equipped with an intelligent temperature control system and a PLC programmable controller, the drying chamber's temperature (50-80℃), humidity (10%-20%), and airflow circulation speed can be precisely controlled, ensuring uniform drying of the timber both internally and externally, significantly reducing defects such as cracking and deformation. Supports high-temperature processing up to 75℃; constant temperature above 55℃ kills mold; 24 hours at 65℃ thoroughly eliminates discoloration and decay fungi, preventing wood deterioration at its source. - Outstanding Production Efficiency: Equipped with a powerful convection circulating fan, hot air is evenly distributed and has strong penetration. No manual turning of the wood is required, shortening the drying cycle to 3-7 days per batch, several times faster than traditional natural drying or simple drying equipment, significantly reducing labor and time costs. - Intelligent and Structural Advantages: Fully automated operation via a PLC computer system. It automatically matches the drying curve based on wood type (e.g., hardwood, softwood), board thickness, and other parameters, requiring no dedicated personnel. Modular installation design allows for easy assembly and disassembly, flexible floor space, and adaptability to various indoor and outdoor installation scenarios. - Safety and Environmental Protection: The fully enclosed drying system eliminates the risk of electric shock. Equipped with multiple early warning devices and safety protection facilities, it completely avoids the fire hazards of traditional combustion drying. No combustion waste is emitted; all-electric operation meets food-grade hygiene standards and environmental policy requirements. - High economic applicability: The equipment is highly compatible, capable of drying various materials besides wood, including vegetables, fruits, medicinal herbs, and meats, significantly improving equipment utilization. Core components utilize imported compressors and high-quality parts, with a system design life of up to 15 years and low daily maintenance costs. 2. Main Application Areas With its stable drying quality and batch processing capacity, this equipment is widely used in furniture manufacturing, building decoration panel processing, and solid wood flooring production. It is particularly suitable for processing high-end woods (such as mahogany, teak, and walnut) where strict requirements are placed on moisture content accuracy and appearance quality. It is a core supporting equipment for large-scale, high-quality wood production.

Core Characteristics of Large-Scale Timber Drying Rooms Large-scale timber drying rooms demonstrate outstanding practical value in the timber processing field. Their core characteristics are concentrated in multiple dimensions, including energy efficiency, drying quality, production efficiency, technological application, safety and environmental protection, and economic applicability. These are elaborated below. Energy Efficiency These drying rooms generally employ heat pump drying technology. Compared to traditional electric heating drying equipment, electricity consumption is reduced by more than 60%, and the all-electric drive mode avoids pollutant emissions at the source. From a technical perspective, the heat pump dryer is based on the reverse Carnot cycle mechanism. It uses a small amount of electricity to drive the compressor, absorbing low-grade heat energy from the air and converting it into usable drying heat. This process makes the equipment's energy efficiency ratio significantly higher than traditional heating methods, achieving highly efficient energy utilization. Drying Quality Characteristics - Precise and Controllable Parameters: Standard configuration includes an intelligent temperature control system and a programmable controller, allowing for precise adjustment of key parameters during the drying process. The temperature control range is typically 50-80℃, and the humidity control range is 10%-20%, while also stabilizing the airflow circulation speed. Precise parameter control ensures a uniform drying environment for the wood, significantly reducing the incidence of drying defects such as cracking and warping. - High-temperature processing capability: Supports high-temperature drying processes up to 75℃. Depending on the wood's preservation requirements, maintaining a temperature above 55℃ for a certain period can kill mold. When the temperature is stabilized at 65℃ for 24 hours, it can completely kill discoloration and decay fungi in the wood, ensuring the stability of wood storage from a microbiological control perspective. Production efficiency characteristics - Optimized labor costs: Equipped with a strong convection circulation fan, the airflow generated by the fan covers the wood evenly, eliminating the need for manual intervention to turn the wood, reducing labor input and lowering labor management costs. - Shortened drying cycle: Combining advanced thermal circulation technology and a large-volume airflow design, the speed at which hot air penetrates the wood is significantly improved, increasing drying efficiency several times compared to traditional equipment. The drying cycle for conventional wood can be controlled within 3-7 days. Technical Application Characteristics - Intelligent Automated Operation: Utilizing a PLC computer control system as the core control unit, operators can preset programs based on basic parameters such as wood type and board thickness. The system will automatically match and adjust drying parameters, achieving fully automated operation without human intervention. - Flexible Structural Installation: Adopting a modular design, each functional module is easy to assemble and disassemble. The overall equipment occupies a small area and can be flexibly installed indoors or outdoors depending on production site conditions, adapting to different scales of processing scenarios. Safety and Environmental Protection Characteristics - Safe and Controllable Operation: Employing a fully enclosed drying system structure, the risk of electric shock is eliminated by design. It is also equipped with a comprehensive fault warning system and safety protection facilities, avoiding the fire hazards associated with traditional combustion heating methods. - Environmental Compliance: No combustion materials are consumed during operation, therefore no waste gas or residue is produced. The all-electric drive mode complies with relevant food hygiene standards, making it a sustainable and environmentally friendly production equipment. Economic and Practical Characteristics - Wide Functional Adaptability: A single drying chamber can be adjusted to meet the drying needs of various materials in different seasons. Besides wood, it can also be used for drying vegetables, fruits, meats, and traditional Chinese medicine, improving the overall utilization rate of the equipment. - Excellent Durability and Maintainability: Core components such as compressors are mostly imported, and the entire system is assembled using high-quality components. The equipment is designed for a service life of up to 15 years, with low maintenance costs over long-term use. Applicable Fields Large-scale wood drying chambers are mainly used in the wood and wood product processing industries such as furniture manufacturing, building decoration, and flooring production. They are especially suitable for high-end wood production scenarios with strict requirements for drying precision and wood stability.

Large-scale timber drying rooms offer significant advantages such as high energy efficiency, excellent drying quality, wide applicability, high level of automation, and safety and environmental friendliness. Energy Efficiency Advantages: Large-scale timber drying rooms utilize advanced heat pump drying technology, reducing electricity consumption by more than 60% compared to traditional electric heating drying equipment. The all-electric operation causes no environmental pollution. The heat pump dryer utilizes the reverse Carnot cycle principle, using a small amount of electricity to drive the compressor and absorb free heat from the air for drying, significantly improving the energy efficiency ratio. Drying Quality Advantages - Precise Control: Equipped with an intelligent temperature control system and programmable controller, it can precisely adjust temperature (typically 50-80℃), humidity (10%-20%), and airflow circulation speed to ensure uniform drying and reduce defects such as wood cracking and deformation. - High Temperature Treatment: Supports high-temperature drying (up to 75℃). Maintaining a temperature above 55℃ for a certain period can kill mold, and maintaining a temperature of 65℃ for 24 hours can completely kill discoloration and decay fungi, effectively preventing wood deterioration and decay. Production Efficiency Advantages - Time and Labor Saving: Utilizes a strong convection circulating fan, ensuring uniform airflow and eliminating the need for manual turning of the wood, significantly saving labor costs. - Short Drying Cycle: Advanced thermal circulation technology and a large air volume design allow hot air to quickly penetrate the wood, resulting in a drying speed several times faster than traditional equipment, with a cycle typically of 3-7 days. Technological Application Advantages - Intelligent Automation: Controlled by a PLC computer system, it can automatically adjust drying parameters according to wood type, thickness, and other parameters, achieving fully automatic operation without the need for dedicated personnel. Flexible Structure: Modular installation, easy to assemble and disassemble, small footprint, can be flexibly installed indoors or outdoors. Safety and Environmental Advantages: - Safe Operation: Fully enclosed drying system, no risk of electric shock, equipped with early warning system and safety facilities, avoiding the fire hazards of traditional combustion methods. - Environmentally Friendly and Pollution-Free: No combustibles or emissions, all-electric operation meets food hygiene standards, a sustainable and environmentally friendly product. Economic Advantages: - Multi-functional: The same drying room can adapt to the drying needs of materials in different seasons, such as vegetables, fruits, meat, and Chinese medicinal materials, improving equipment utilization and reducing investment costs. - Durable and Low-Maintenance: Uses imported compressors and high-quality components, the system life can reach 15 years, with low maintenance costs. Large-scale wood drying rooms are widely used in the furniture manufacturing, building decoration, flooring production and other wood and wood product industries, and are especially suitable for high-end wood production with strict requirements for drying quality.

Currently, the best equipment for drying sweet potato vermicelli is the air-energy heat pump dryer. This equipment utilizes advanced heat pump technology and operates through a reverse Carnot cycle, significantly improving energy efficiency compared to traditional electric heating equipment. Advantages: - Energy-saving and environmentally friendly: Compared to traditional electric heating methods, it offers significant energy savings and low operating costs. It utilizes a combination of air and electricity, making it safe and reliable, and it does not release harmful gases. - High drying quality: Utilizing low-temperature, high-air-volume drying technology, it precisely controls temperature, humidity, and air speed for uniform drying, avoiding color loss or quality degradation caused by high temperatures. - Intelligent: Equipped with a PLC touchscreen control system, it offers automated management, intelligent temperature control, and easy operation. - Versatile: Customizable units with different power outputs and drying chamber sizes can be tailored to suit various production scales, depending on the batch size. Other optional equipment: - Hot air circulation dryer: Offers low energy consumption, high drying efficiency, and simple operation, making it widely used for drying sweet potato vermicelli. - Microwave dryer: Particularly suitable for rainy southern regions, it offers rapid dehydration and mold prevention, completing drying in just 22 minutes. - Airflow dryers: Utilizing a pulsed airflow principle, they are ideal for drying starchy materials, preventing sticking or sticking to the drum wall. Based on actual application feedback, air-source heat pump dryers offer the best performance in terms of energy efficiency, drying quality, and intelligent control, making them a leading choice in the market.

Heat-treated wood, also known as carbonized wood or physically modified wood, is a type of modified material that undergoes a prolonged pyrolysis treatment at temperatures between 160°C and 230°C in an oxygen-free or low-oxygen environment to improve its physical, mechanical, and durability properties. This process, which does not rely on chemical additives, is an environmentally friendly wood modification technology widely used in construction, decoration, and outdoor projects. The core mechanism is that high temperatures cause changes in the wood's internal chemical composition: hemicellulose degrades, reducing the number of hydroxyl groups, significantly reducing hygroscopicity and expansion and contraction rates, improving dimensional stability; lignin undergoes cross-linking, enhancing structural stability; and nutrients are destroyed, effectively inhibiting fungal and insect attack, achieving natural anti-corrosion properties. After treatment, the wood's equilibrium moisture content is controlled at 4% to 7%, its density is reduced by approximately 10% to 15%, and its thermal conductivity is lowered, resulting in excellent thermal insulation properties. The process consists of three stages: first, drying at 100°C to 130°C to reduce the moisture content to below 3%; then, maintaining the wood at a high temperature of 180°C to 210°C for 2 to 6 hours to achieve pyrolysis; and finally, humidity control to restore the moisture content of the wood. This equipment typically uses a closed reactor, with a PLC system precisely controlling temperature, pressure, and oxygen content. Depending on the treatment conditions and intended use, heat-treated wood can be categorized as surface carbonized wood or deep carbonized wood. The former, which is only carbonized on the surface, is often used in handicrafts; the latter, which is uniformly carbonized throughout its structure and is also known as homogeneous carbonized wood, is suitable for indoor and outdoor decoration, flooring, furniture, and landscaping. However, this material is not recommended for direct contact with soil or prolonged submersion in water.

Hot air furnaces for wood drying offer the following advantages: High efficiency and energy saving - High fuel utilization: Utilizing advanced combustion and heat exchange technologies, fuel is fully burned, resulting in high thermal efficiency and reduced energy waste. - Waste heat recovery: Equipped with a heat recovery device, heat energy is recovered during the drying process, further improving heat utilization and reducing fuel consumption. Excellent drying results - Stable temperature: Precise hot air temperature control with minimal fluctuation ensures uniform heating of the wood, improving drying quality. - Uniform drying: A forced circulation system distributes the hot air evenly within the drying chamber, preventing overheating or uneven drying of the wood. Wide applicability - Diverse fuels: Wood processing waste such as sawdust, bark, and shavings, as well as coal, can be used as fuel, reducing operating costs. - High adaptability: Suitable for wood of varying species, board thickness, and moisture content, allowing for flexible use of various drying processes. Easy operation - High degree of automation: Features such as automatic feeding and automatic adjustment reduce manual intervention and labor intensity. - Easy Maintenance: The rational structural design facilitates inspection and maintenance, extending the equipment's service life. Environmentally Friendly - Low Emissions: Utilizing environmentally friendly technologies, emissions of harmful gases such as smoke and sulfur dioxide are low, meeting environmental standards. - Resource Recycling: Utilizing wood processing waste as fuel, this achieves resource recycling and reduces environmental pollution. Multi-Purpose Machine - Versatility: In addition to wood drying, it can also be used for workshop heating or drying other materials, improving equipment utilization. In summary, the wood drying hot air furnace, with its high efficiency and energy saving, excellent drying results, wide applicability, ease of operation, environmental friendliness, and versatility, is an ideal drying equipment for wood processing companies.

Wood modification equipment achieves performance leap by multi-dimensional precise control of physical, chemical or biological processes to deeply optimize wood molecular structure:​ Physical Modification (Thermal Treatment/High-pressure Densification)​ Thermal treatment: Gradually heat wood to 160-240℃ (adjusted by wood species) in a nitrogen or steam-protected closed environment, permanently reducing hydrophilic groups in wood by degrading part of hemicellulose and rearranging lignin molecular chains.​ High-pressure densification: Compress cell structure with 10-30MPa pressure after softening wood at high temperature, increasing wood density by 30%-60%.​ ✅ Core advantages: More environmentally friendly without chemical additives; treated wood has stable moisture content of 8%-12%, weather resistance increased by 2-3 times, and hardness increased by over 40%.​ Chemical Modification (Acetylation/Resin Impregnation)​ Acetylation: Place wood in acetic anhydride solution for 3-6 hours of acetylation reaction at 80-120℃, replacing hydroxyl groups (-OH) in wood cells with acetyl groups to cut off moisture adsorption paths.​ Resin impregnation: Inject environmentally friendly resin into wood conduits through vacuum-pressure process, forming "skeleton support" after curing to fill cell gaps.​ ✅ Core advantages: Dimensional stability over 90%, water absorption reduced by 60%-70%, and insect resistance and anti-corrosion life extended to over 20 years.​ Intelligent Integrated System​ Equipped with PLC control system and multi-sensor array, real-time monitoring of temperature (±1℃), pressure (±0.01MPa), humidity (±2%RH) and other parameters, automatically adjusting process curves to ensure performance deviation of each cubic meter of wood ≤5%.​ ✅ Core advantages: Production efficiency increased by 30%, energy consumption reduced by 20%, labor cost reduced by 40%, realizing large-scale stable production.​  

Key Features of Wood Drying Machines: Drying Chamber: Wood drying machines consist of a drying chamber or kiln where the wood is placed for drying. The chamber is designed to create a controlled environment to optimize the drying process. It may be constructed with insulated walls and airtight seals to prevent heat and moisture loss. Heating System: Wood drying machines utilize a heating system to raise the temperature inside the drying chamber. The heating system can be powered by various energy sources such as electricity, natural gas, or biomass. It provides the necessary heat energy to evaporate moisture from the wood. Air Circulation: Proper air circulation is crucial for effective wood drying. Wood drying machines are equipped with fans or blowers that circulate heated air throughout the drying chamber. This ensures even distribution of heat and moisture removal, facilitating uniform drying of the wood. Humidity Control: Wood drying machines have humidity control mechanisms to regulate the moisture levels inside the drying chamber. This can be achieved through the use of sensors, controllers, and humidifiers or dehumidifiers. Maintaining an optimal humidity level helps prevent over-drying or under-drying of the wood. Monitoring and Control Systems: Advanced wood drying machines are equipped with monitoring and control systems. These systems allow operators to monitor and adjust various parameters such as temperature, humidity, airflow, and drying time. They ensure precise control over the drying process and help optimize drying efficiency. Safety Features: Wood drying machines prioritize safety during operation. They may include safety interlocks, temperature sensors, and emergency shut-off systems to prevent overheating, fire hazards, or other potential risks. Safety features help protect both the equipment and the operators.