Straw pellet production line
Solutions for processing corn stover, rice straw, elephant grass and alfalfa into straw pellets and hay pellets

Customized Straw Pellet Production Line
As people’s environmental awareness increases and the demand for renewable energy rises, straw pellets and hay pellets, as a clean and sustainable biomass energy, are increasingly widely used. Huaxin Machinery’s straw pellet production line solution is designed to efficiently convert waste straw and hay resources into high-value-added pellet fue.
Annual Production Capacity of Straw Pellet Production Line
Annual production capacity
Annual output of 10,000 tons, suitable for start-ups or small processing plants, with relatively low investment costs, can meet local market demand within a certain range, such as small heating enterprises, rural biomass fuel market, etc.
Annual output of 30,000 tons, suitable for enterprises with a certain market base and stable customer base, can stably supply regional markets, such as medium-sized industrial boiler fuel demand, regional biomass power plants, etc.
With an annual output of more than 50,000 tons, it is tailor-made for large energy companies and biomass fuel groups. It has a high level of automation and intelligence, and can efficiently meet large-scale market demands such as urban centralized heating and energy supply for large industrial enterprises.
Equipment Configuration of Straw Pellet Production Line
Equipment Configuration
Raw material receiving and pre-processing
- Raw material storage site: an open-air or covered raw material storage site with a suitable construction area, hardened ground, and a complete drainage system to prevent rainwater from soaking the straw and causing mold and deterioration.
- Belt conveyor: a high-strength, wear-resistant rubber conveyor belt is used. The belt width is selected between 400 and 800 mm according to the production scale, and the length is customized according to the site layout. The straw raw materials can be efficiently and smoothly transported from the stacking site to each production link.
- Bucket elevator: used to lift straw raw materials vertically, the lifting height is generally between 8-20 meters, and the bucket capacity is selected between 0.3-1.5 cubic meters according to the production capacity. The raw materials at low places are lifted to higher equipment such as crushers and dryers to ensure the smooth progress of the production process.
- Straw crusher: specially designed for the physical properties of straw, it adopts hammer or blade crushing structure, which can quickly crush the whole bundle of straw into shorter segments. The crushing length is generally between 10-50 mm, which is convenient for subsequent further crushing processing.
- Crusher: After the initial crushing, the straw segments enter the crusher. The crusher can choose a ring hammer crusher or a tooth claw crusher to further crush the straw into a small and uniform powder. The finished product particle size can be controlled between 1-5 mm.
- Screening equipment: Use a vibrating screen to screen the crushed straw raw materials to remove impurities, large particles that are not fully crushed, and possible foreign matter, to ensure that the raw materials entering the granulation stage are uniform in particle size and high in purity.
Drying
Rotary dryer: It consists of a cylinder, a lifting plate, a transmission device, a heating device, etc. The cylinder is made of high-quality carbon steel or stainless steel, installed at an angle, and equipped with a lifting plate inside, which allows the material to fully contact with hot air during the rotation of the cylinder to achieve rapid drying.
Airflow dryer: It uses high-speed hot air flow to make the material fully contact with hot air in a fluidized state to achieve instant drying. It has the characteristics of fast drying speed, high efficiency, and strong adaptability to materials. It is suitable for large-scale continuous production operations and can quickly evaporate the moisture in the raw materials.
Pelletizing
- Ring die pelletizer: It is one of the core equipment for straw pellet production, consisting of a ring die, a pressure roller, a transmission device, a feeding device, a tempering device, etc. The ring die is made of high-quality alloy steel and has a high-precision die hole. The hole diameter is selected between 4 and 10 mm according to the product specifications, and straw pellets of different diameters can be produced.
- Flat die pelletizer (optional): For some small production lines or occasions where the requirements for pellet shape are not high, a flat die pelletizer can be selected. The flat die pelletizer has a relatively simple structure and low cost.
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Cooling and screening
- Counterflow cooler: It is composed of a machine body, cooling fan, discharging device and control system. The machine body is designed with cooling air duct and material channel. The cooling fan sends cold air into the cooling air duct, and forms a countercurrent flow with the hot straw particles in the material channel. Through efficient heat exchange, the heat in the particles is quickly taken away, and the particles are quickly cooled to near room temperature.
- Air-cooled cooler (optional): The air-cooled cooler is composed of a fan, cooling air duct and material conveying device. The fan blows cold air into the cooling air duct. Driven by the conveying device, the material passes through the cooling air duct and exchanges heat with the cold air, thereby achieving cooling.
- Vibrating screen: It adopts a double-layer or multi-layer screen structure. The screen material is usually a stainless steel wire woven mesh or a punched plate. According to the finished product specification requirements of the straw pellet product, select the appropriate screen aperture. Ensure the uniformity, integrity and appearance quality of the finished particles and improve the qualified rate of the product.
Bagging
Automatic quantitative bagging machine: it can quickly adjust the packaging specifications according to the market demand, and the metering accuracy is controlled within ±0.2% to ensure that the weight of each bag of products meets the standard, reduce the error and improve customer satisfaction.
Palletising equipment: the packed products are sent to the palletising area via belt conveyor, and the palletising equipment can be chosen from automatic palletising robot or mechanical palletiser.
Production Process of Straw Pellet Production Line
Production process
Raw material receiving and pre-treatment
Various types of straw raw materials, such as corn straw, wheat straw, rice straw, elephant grass and alfalfaetc., are transported to the raw material receiving area of the factory. Then the raw materials are inspected for quality and preliminarily classified. Qualified raw materials are sent to the raw material pretreatment area through conveying equipment such as belt conveyors and bucket elevators. They are first crushed into shorter segments by straw crushers, and then crushed into powder with uniform particle size by pulverizers. The crushed raw materials are screened by vibrating screens to remove oversized particles and impurities.
dry
The pre-treated raw materials are transported to the drying area and enter the dryer for drying. According to the initial moisture content of the raw materials and the final moisture content required by the product, the appropriate drying temperature and time are selected. Through heating methods such as steam, hot air furnace or gas, the hot air is fully in contact with the raw materials to quickly evaporate the moisture in the raw materials, so that the moisture content of the raw materials is reduced to between 10% and 18%, meeting the moisture requirements of the granulation process for the raw materials.
Pellet making
The dried raw materials enter the pellet mill through the conveying equipment. In the pellet mill, the raw materials are first tempered by the tempering device, and an appropriate amount of binder (such as lignin, starch, etc.) and water are added to make the raw materials have appropriate humidity and viscosity. Then, under the strong pressure of the ring die and the pressure roller, they are squeezed through the die holes on the ring die to form dense straw pellets.
Cooling and screening
The hot straw pellets coming out of the pellet mill enter the cooling area through the conveying equipment, and are cooled by a countercurrent cooler or an air-cooled cooler, so that the pellets are quickly cooled to near room temperature, improving the stability and water resistance of the pellets. The cooled pellets enter the screening equipment and are screened by a vibrating screen to remove unqualified large particles, fine powder, and particle clumps that stick together, ensuring the uniformity, integrity, and appearance quality of the finished straw pellets and improving the qualified rate of the product.
Bagging
After screening, qualified straw pellets enter the packaging area through the conveying equipment, and first enter the automatic quantitative bagging machine, where they are measured and filled into bags according to the set packaging specifications and weight. The packaged products are transported to the bag sewing machine through the conveyor belt for sealing. The packaged finished products are transported to the palletizing area through the conveying and palletizing equipment. The automatic palletizing robot or mechanical palletizer neatly stacks the packaging bags on the pallet to form a stable palletizing unit, which is convenient for forklift handling and warehouse management.
Raw Material Type of Straw Pellet Production Line
Raw material type
Corn straw
It has high yield, high fiber content, certain toughness and strength, and can be made into high-quality pellet fuel after processing.
Rice straw
Rice straw usually contains high moisture and silicon content, and needs to be fully dried and pretreated before producing straw pellets.
Wheat straw
It can be mixed with other straw raw materials in the production of straw pellets to adjust the physical properties and combustion characteristics of the pellets.
Other straws
Such as sorghum straw, soybean straw, elephant grass, damson grass, alfalfa, etc.etc., can also be used as a supplementary raw material for straw pellet production.
Finished Product Specifications of Straw Pellet Production Line
Finished product specifications
Particle shape
Cylindrical, 8-25 mm long, 4-10 mm in diameter, smooth surface without cracks, good uniformity, stable and efficient combustion, and improved energy utilization.
Particle density
About 0.8-1.2g/cm3, suitable density, easy to store and transport, reduce crushing loss, improve market competitiveness and added value.
Moisture content
10%-18%, balanced molding, combustion and storage performance, prevent mold, deterioration and spontaneous combustion, and ensure product safety and stability.
Ash content
Schematic Diagram of Production Process of Straw Pellet Production Line
Production process diagram

Successful Cases of Straw Pellet Production Line
Successful Cases
For more detailed information on straw pellet and hay pellet production lines or to get a customised solution, please feel free to contact our technical team.