Wood Pellet Machine

Wood pellet fuel now has been a great power to provide people an alternative fuel to traditional fuels in the world. Due to increasing popularity of pellet fuel, wood pellet mill is widely applied today. The flat die pellet mill is designed for compressing wood materials into pellets as heating fuel. It is composed of clutch assembly, gear box, main spindle box, rollers, upper body, feeder, flat die, engine and base. Feeding the feedstock into the feeder, rollers will compress materials and extrude it through die holes to get wood pellets. The key components-flat die and rollers are made of alloy steel which has strong and malleable texture. The pellet mill is driven by heavy-duty gearbox, which can produce continuously.
Famous with simple operation, high automation degree and less labor force, wood pellet mill is suitable for home use or small enterprises which produce biomass pellet fuel. Wood pellet mill can be configured to diesel power or electricity power. It has wide application to process not only wood chips, wood shavings and wood sawdust but also stalk from cotton or bean, peanut shell, sunflower husk and so on.
 

Outstanding Performance of Portable Wood Pellet Mill

wood pellet mill ●Continuous and steady running for over 24 hours can be achieved.
●High security, low noise and low energy consumption.
●Standardized rollers and dies make replacement available.
●Size and length of pellets is adjustable by changing dies with different specification.
●Good visibility. Using the pellet mill for production, you can monitor the  pelleting process directly by watching pelleting chamber, which will help to  solve production trouble immediately


Main Steps of Wood Pellet Production

Raw material(waste) collection→size reduction by a hammer mill→dry raw materials→pelletizing by wood pellet making machine→pellet cooling and packing
Please Note: 1. Reduce material size into 3-5mm in crushing
2. Moisture of bamboo should be reduced to 12% around in drying
3. No binder in pelletizing as lignin in wood plays a role of binder to assist pelletizing.


Characteristics of Wood and Wood Wastes

♦ Wood Materials

wood material

Wood material is typically composed of cellulose, hemi-cellulose, and lignin, with a small amount of mineral ash. Please see the following table about typical percentages of theses components.

Wood components
Softwood %
Hardwood%
Cellulose
45-60
40-55
Hemi-cellulose
35-40
20-40
Lignin
25-30
15-30
Ash
0.1-1.0
0.5-1.5







Depending upon the species, these components can vary. For example, pin leaf tree’s main wood calorific value is about 5,000kcal/kg. Normal leaf tree’s calorific value is 4,660kcal/kg. Pin leaf tree’s main wood calorific value is 7% higher than normal leaf main wood. Because pin leaf tree’s wood has high extractive material value.
♦ Wood Wastes 

 

wood chip

Wood wastes are mostly produced from Sawmilling, Plywood production, Particleboard production, including sawdust, wood shavings, bark, trimming and so on.
A. Calorific values of various wood waste types
Dry type
Calorific Value (kj/kg) 
Wood waste derived from treated wood
17525
Chipped demolition wood derived from treated wood
17792
Park waste wood derived from untreated wood
18278
Wood industrial wood waste, dust
18391







B. Physical properties of various wood waste types

Type
Moisture (%)
Density (kg/m3)
Ash (%)
Sawdust
50.33
1.56
1.12
Large wood, bark
46.89
2.88
37.93
Mixed wood, bark
46.72
1.81
9.32







Features of Wood Pellets

Wood pellets have higher calorific value ranging from 3900-4800 kilocalorie/kg. The carbon content is 75-85%, ash content is 3-6%, and moisture content is 1-3%.
1. Spotlights of Wood Pellet

wood pellet

● high quality (shape and hydrous rate are stable)
● burning under environmental compliance is possible
● suitable for automatic combustion operation
● made of regional renewable resources
● energy density is higher than wood chips, suitable for transportation and storage
● possibility to be an alternative for energy system from smaller to larger scale


2. Wide application
● Wood pellet is mainly used as fuel for heating in home pellet stove and medium or small-scale electric power plant. The benefits of wood pellets for heating are affordability, sustainability and convenience.
● Wood pellet can also be used for animal bedding. They are manufactured at high temperature to provide a sterile and low dust environment. Biodegradable nature of wood pellets means that it is easy to dispose of and can be used as a fertilizer or on the compost heap