The GRL series hot-air furnace is a high-efficiency, energy-saving, new-type heat-exchange device independently developed by our factory. It uses coal, biomass, gas, or oil as fuel and delivers clean, pollution-free hot air through radiation heat transfer, conduction heat transfer, and convection heat transfer.

Product Introduction

The GRL series hot-air furnace is a high-efficiency, energy-saving, new-type heat-exchange device independently developed by our factory. It uses coal, biomass, gas, or oil as fuel and delivers clean, pollution-free hot air through radiation heat exchange, conduction heat exchange, and convection heat exchange. The clean hot-air furnace designed and manufactured by our company has been granted a national patent.

Thanks to the optimization measures and innovative design adopted in this series of hot-air furnaces, heat transfer and heat exchange performance have been significantly enhanced, resulting in a high overall heat-transfer coefficient, rapid temperature rise, and substantial thermal storage capacity for the entire unit.

The GRL series hot-air furnace, as a new type of heat-source equipment, can replace steam heat exchangers, thermal-oil heat exchangers, and electric air heaters, offering advantages such as compact size, easy installation and transportation, and low energy consumption. It is widely applicable in various operations including drying, heating, heat preservation, and dehumidification, and when paired with drying equipment such as cyclone flash dryers, pressure spray dryers, and vibrating fluidized-bed dryers, it can maximize the performance of the entire system.

Working Principle

The GRL series hot-air furnaces are available in two configurations: vertical and horizontal. The vertical coal-fired (or biomass-pellet-fired) hot-air furnace can further be customized as either a manual-firing unit or an mechanically-fired unit, depending on customer requirements. Each furnace consists of two main components: the combustion chamber and the heat-exchanger assembly. High-temperature flue gases generated in the combustion chamber enter the heat-exchanger assembly, where they undergo multi-pass counterflow heat exchange with cold air supplied by a blower through both radiation and convection. After being heated to the desired temperature, the cold air is discharged through the hot-air outlet of the furnace and delivered to the thermal-use equipment. The flue gases are drawn out by an induced-draft fan and then passed through a flue-gas separator and a dust collector before being vented to the atmosphere.

The hot air does not come into direct contact with the material, thereby preventing flue-gas contamination; this makes it suitable for materials with stringent requirements regarding whiteness and freedom from impurities.

Product Features

• Pure and contamination-free: Hot air is separated from combustion products, ensuring that the material remains uncontaminated.
• High efficiency and energy savings: large heat-exchange area and high heat-transfer efficiency, with some models achieving thermal efficiencies of 85% or higher.
• Temperature control: The hot-air temperature is precisely regulated via an intelligent PLC control system, with an output range of 100–450°C.
• Special Note: Our equipment features a multi-layer, sleeve-type all-metal construction (without refractory materials), thereby eliminating common issues associated with traditional equipment—such as cracking and spalling caused by differential thermal expansion and contraction due to varying material coefficients of thermal expansion. Each air-gap sleeve is densely fitted with metal fins, maximizing heat-exchange efficiency. The high-temperature zone is constructed from high-temperature-resistant stainless steel (310S), ensuring a long service life.

Application Fields

• Food industry: drying of milk powder, bread, biscuits, and other products.
• Pharmaceuticals and chemicals: drying of pharmaceuticals, synthetic resins, and other materials.
• Other fields: grain drying, wood processing, industrial heating, and more.

Strengths and Weaknesses

• Advantages: high-quality manufactured materials, wide applicability, and excellent environmental performance.
• Disadvantage: High equipment cost.

Selection Recommendations

• Select the appropriate type based on material characteristics, such as requirements for whiteness, impurities, and contamination.
• Considering fuel type (coal, natural gas, etc.) and thermal efficiency, natural-gas-fired systems are cleaner but more expensive.
• Pay close attention to the material and design of the heat exchanger to ensure long-term stable operation.

 

Biomass Pellet Hot Air Furnace: An Efficient Heating Solution for Modern Drying Applications

As industries continue to seek cleaner and more cost-effective energy solutions, the Biomass Pellet Hot Air Furnace is becoming an increasingly popular choice for drying and heating applications. Utilizing renewable biomass pellets as fuel, this system converts biomass energy into a stable source of hot air, providing an environmentally friendly alternative to traditional coal, oil, and gas-fired heating equipment.

The Biomass Pellet Hot Air Furnace is designed to generate continuous hot air for industrial drying processes. By burning biomass pellets efficiently, the furnace produces high-temperature airflow that can be directed into drying chambers, grain dryers, wood processing facilities, agricultural product drying systems, and various industrial production lines. Biomass hot air furnaces are widely recognized for their ability to provide stable heat while reducing dependence on fossil fuels.

One of the key advantages of the system is its fuel flexibility and operational economy. Biomass pellets are produced from renewable materials such as sawdust, agricultural residues, wood waste, and crop by-products. Compared with conventional fuels, biomass energy can help lower operating costs while supporting sustainability goals. In addition, modern furnace designs focus on improving combustion efficiency, ensuring more complete fuel utilization and stable temperature control throughout the heating process.

The furnace is particularly suitable for industries that require reliable drying performance. Applications include grain drying, food processing, wood drying, feed production, chemical materials, and agricultural product processing. Stable hot air supply helps improve drying consistency while supporting product quality and production efficiency. Many drying facilities are also adopting biomass heating systems to reduce energy expenses and meet increasingly strict environmental requirements.

Another important benefit is environmental performance. Biomass pellets are considered a renewable energy source, and their use can contribute to reducing dependence on non-renewable fuels. Advanced combustion systems and optimized airflow management further enhance thermal efficiency while helping minimize emissions. Research into biomass combustion technology continues to focus on improving fuel utilization and heat transfer performance, making biomass heating solutions increasingly attractive for industrial users.

As energy costs and environmental concerns continue to influence industrial decision-making, the Biomass Pellet Hot Air Furnace offers a practical balance of efficiency, sustainability, and operational reliability. By delivering consistent hot air, reducing fuel expenses, and supporting cleaner energy utilization, it has become a valuable heating solution for modern drying and processing industries.