What is wood pellets?
Wood pellet is a new type of the biomass energy with unique advantages of clean, renewable, and eco-friendly. Wood pellets are becoming more and more popular in global markets. Wood pellets are produce by using wood wastes such as sawdust, shavings, and wood chips, which are the by-products of the manufacture of lumber, furniture, and other forest products are all available. Wood pellets manufacturing is a complex process, which mainly consists of the following parts: raw materials preparation, grinding, drying, pelletizing, cooling, screening, and packaging.
1. Efficient. Wood pellets are an efficient source of heat because they contain very low levels of moisture and ash, when compared to woodchips or cordwood. Virtually all of the material is burned and converted to heat.
2. Cost-effective. Wood pellets are economically competitive with home fossil fuel options and electric heat.
3. Environmental friendly. Wood pellet are a sustainable fuel source, and burning wood pellets is carbon neutral.
4. Renewable. Wood pellets are a biomass product made of wood waste or other forest-thinning byproducts. According to data collected by the Pellet Fuels Institute, wood pellets are an unlimited fuel source.
5. Broad application. Wood pellets can be used in a lot of appliances such as stoves, furnaces, and other heating systems.
1. Efficient. Wood pellets are an efficient source of heat because they contain very low levels of moisture and ash, when compared to woodchips or cordwood. Virtually all of the material is burned and converted to heat.
2. Cost-effective. Wood pellets are economically competitive with home fossil fuel options and electric heat.
3. Environmental friendly. Wood pellet are a sustainable fuel source, and burning wood pellets is carbon neutral.
4. Renewable. Wood pellets are a biomass product made of wood waste or other forest-thinning byproducts. According to data collected by the Pellet Fuels Institute, wood pellets are an unlimited fuel source.
5. Broad application. Wood pellets can be used in a lot of appliances such as stoves, furnaces, and other heating systems.
The Standard of Good Quality Wood Pellets
To produce good quality pellets, the following standards must be upped to:
* An ash content of less than 1%
* Pellet diameter ranging from 6-8mm
* Pellet length not exceeding 40 mm
* Moisture content not to exceed 8%
* Bulk density of at least 1000 kg/litre
* Calories value exceed 4000 Kcal/kg
* No metal objects
* An ash content of less than 1%
* Pellet diameter ranging from 6-8mm
* Pellet length not exceeding 40 mm
* Moisture content not to exceed 8%
* Bulk density of at least 1000 kg/litre
* Calories value exceed 4000 Kcal/kg
* No metal objects
Factors Affecting Pellets Production
A number of factors significantly impact the quality of wood pellets in production. The factors include particle raw material size, moisture content of raw material, feeding rate and pressure, roller, die and so on.
1)Particle raw material Size
Particle size is one of the most significant factors affecting overall pellet quality. Smaller sizes generally correspond with greater pellet strength and durability as larger particles serve as fissure points. To produce quality wood pellets, hammer mill is needed to reduce the size of raw material if the size of raw material is greater than 3mm – 4mm and mixture of particle sizes can increase inter-particle bonding.
2)Moisture content
Moisture content of raw material is key factors that affect wood pellet production. Most of the productions fail because unsuitable moisture content raw material is feeding directly into pellet mill. Normally the dry material are needed for wood pellets production, however the experienced operator is needed to adjust the most suitable percentage of moisture content to suit the machine. Unfortunately, in Malaysia market, the sawdust is selling by measuring the weight and therefore, the smart & clever transporter is adding water into sawdust to get the weight which can generate higher pricing. So that, when purchasing the sawdust from a sawmill, please consider the ‘skills’ of the lorry driver which create moisture content problem.
3)Feeding rate and pressure
Consistent feeding rate and pressure can ensure smooth production. So that, Inverter are using in feeding conveyor to control the feeding rate into pellet mill. The machine’s pressure is consistent when the feeding rate is consistent. This can observe by the Amp meter beside the pellet mill. Under good pressure, high density of wood pellets can obtain.
4)Roller & Die
Normally people not understand what is die even when I present to a engineering shop in Malaysia looking to make a die, the experts also don’t understand what I means, maybe in Malaysia terms I say ‘mould’ then all people will ‘Ohhh’, so the die means the mould in the pellet machine. Roller is the tools that stick with die and the function is to press the sawdust into die. Good roller & die can last longer and not easy to be out of shape. Usually good roller and die are making using alloy steel and manage to use more than 800 hours depends on the operation & adjustment of roller’s pressure. There is specific knowledge in choosing suitable roller & die for pellet mill. Good pellet die manage to produce high quality wood pellets.
1)Particle raw material Size
Particle size is one of the most significant factors affecting overall pellet quality. Smaller sizes generally correspond with greater pellet strength and durability as larger particles serve as fissure points. To produce quality wood pellets, hammer mill is needed to reduce the size of raw material if the size of raw material is greater than 3mm – 4mm and mixture of particle sizes can increase inter-particle bonding.
2)Moisture content
Moisture content of raw material is key factors that affect wood pellet production. Most of the productions fail because unsuitable moisture content raw material is feeding directly into pellet mill. Normally the dry material are needed for wood pellets production, however the experienced operator is needed to adjust the most suitable percentage of moisture content to suit the machine. Unfortunately, in Malaysia market, the sawdust is selling by measuring the weight and therefore, the smart & clever transporter is adding water into sawdust to get the weight which can generate higher pricing. So that, when purchasing the sawdust from a sawmill, please consider the ‘skills’ of the lorry driver which create moisture content problem.
3)Feeding rate and pressure
Consistent feeding rate and pressure can ensure smooth production. So that, Inverter are using in feeding conveyor to control the feeding rate into pellet mill. The machine’s pressure is consistent when the feeding rate is consistent. This can observe by the Amp meter beside the pellet mill. Under good pressure, high density of wood pellets can obtain.
4)Roller & Die
Normally people not understand what is die even when I present to a engineering shop in Malaysia looking to make a die, the experts also don’t understand what I means, maybe in Malaysia terms I say ‘mould’ then all people will ‘Ohhh’, so the die means the mould in the pellet machine. Roller is the tools that stick with die and the function is to press the sawdust into die. Good roller & die can last longer and not easy to be out of shape. Usually good roller and die are making using alloy steel and manage to use more than 800 hours depends on the operation & adjustment of roller’s pressure. There is specific knowledge in choosing suitable roller & die for pellet mill. Good pellet die manage to produce high quality wood pellets.
Common parts in pellets mill
A pellet mill, also known as a pellet making machine, is a machine used to produce pellets from raw materials. Their basic function actually occurs at the nip between the die and the rollers. There are some important common parts of operation on pellet mills.
1)Roller
Installed on bearings, roller is cylindrical shaped equipment.
To help raw materials get into die hole is the main purpose of the roller. Therefore, the shape and construction of the roller is designed for preventing slippage of raw materials and to give a rough surface for better traction. That is to say, the only driving force on the roller assembly is the friction from contact with a very thin mat of feed between the die and roll.
2)Die
Standard definition of a die is that of metal perforated shape units with holes through which raw material is forced to produce pellets.
It is the driving component, getting its power from the main driver motor in the pellet mill. In general, the holes and thickness of the die determine the final characters of pellets.
3)Knives
Knives here we called is a blade that is installed outside the die area for the purpose of cutting the pellet to a given size. In addition, knives also help in avoiding excessive fines by limiting the size of a pellet before it gets to long and it breaks against the side of the pellet press door.
4)Feeding Screw Conveyor
The feeder screw conveyor allows raw materials to go from the hopper into the pellet machine with a given speed and volume. In fact, feeder screw is considered to be a throttle for the pellet mill.
5)Bearings of Pellet Mills
Bearings do their work silently in tough environments, since they are hidden in machinery where we cannot see them visually. Nevertheless, bearings are crucial for the stable operation of machinery and ensure its top performance. The basic function of bearings is principally to reduce mechanical friction. Reducing friction means the following. First, the machinery will run more efficiently and smoothly. Second, there will be less friction wear, thus extending the operating life of the machinery. Last, it can prevent abrasion burn, avoiding mechanical breakdown. During the pelletizing process, bearings basically help the shaft to rotate easily. Also, bearings contribute to lowering energy consumption and allow efficient transmission of power.
1)Roller
Installed on bearings, roller is cylindrical shaped equipment.
To help raw materials get into die hole is the main purpose of the roller. Therefore, the shape and construction of the roller is designed for preventing slippage of raw materials and to give a rough surface for better traction. That is to say, the only driving force on the roller assembly is the friction from contact with a very thin mat of feed between the die and roll.
2)Die
Standard definition of a die is that of metal perforated shape units with holes through which raw material is forced to produce pellets.
It is the driving component, getting its power from the main driver motor in the pellet mill. In general, the holes and thickness of the die determine the final characters of pellets.
3)Knives
Knives here we called is a blade that is installed outside the die area for the purpose of cutting the pellet to a given size. In addition, knives also help in avoiding excessive fines by limiting the size of a pellet before it gets to long and it breaks against the side of the pellet press door.
4)Feeding Screw Conveyor
The feeder screw conveyor allows raw materials to go from the hopper into the pellet machine with a given speed and volume. In fact, feeder screw is considered to be a throttle for the pellet mill.
5)Bearings of Pellet Mills
Bearings do their work silently in tough environments, since they are hidden in machinery where we cannot see them visually. Nevertheless, bearings are crucial for the stable operation of machinery and ensure its top performance. The basic function of bearings is principally to reduce mechanical friction. Reducing friction means the following. First, the machinery will run more efficiently and smoothly. Second, there will be less friction wear, thus extending the operating life of the machinery. Last, it can prevent abrasion burn, avoiding mechanical breakdown. During the pelletizing process, bearings basically help the shaft to rotate easily. Also, bearings contribute to lowering energy consumption and allow efficient transmission of power.
Types of pellet mill
Pellet mills can be divided into two types: flat die pellet mill and ring die pellet mill. Many people who did not learn the pellet mills well will feel confused: what are the main differences between flat die pellet mill and ring die pellet mill? If someone want to start a pellets production line, how should they make a right choice? Everything has two sides, advantages and disadvantages. Only if apply things to corresponding situations, they can play the significant roles
Ring Die Wood Pellet Mill
Ring die pellet mills are of vertical structure and they combine with the flat die pellet mills’ vertical feeding method. The original circle structure of ring die pellet press is specially designed for those wood materials like gum wood, palm which are hard to press. Because the proportion of the materials is light, so vertical feeding method is selected. In addition, due to the nice stability of circle structure ring die pellet mills, thus the design adopts combination of ring die and flat die. Ring die pellet mill has both advantages and disadvantages as below:
1.Large production, nice pellet forming shape and high density( 1-1.3%).
2. The roller and ring die are of balanced wear.
3.The main disadvantage is the relatively high power consumption if the output cannot meet target, the ring die costing relatively higher than flat die and will cracking if there are not proper in use, high amps needed to setup for ring die machine.
Flat Die Wood Pellet Mill
Compared with ring die wood pellet mills, the flat die pellet mills are applied to small and medium sized production which requires lower hourly output and the materials with large adhesive force.
Also, flat die pellet mill has its own advantages and disadvantages. On the whole, flat die pellet mill is of low energy consumption, greater mobility, so it is suitable for small and medium operation in enterprises and factories.
1. Pellet machine only need lower energy consumption motor compare to ring die machine.
2. Low wear and tear of roller, dies and bearings.
3. Flat die is cheaper than ring die and there are no common problem facing with ring die – cracking.
In a word, ring die wood pellet mills advantages are the flat die wood pellet mills disadvantages, and vice versa. You must consider all the factors that will limit your production carefully.
Ring Die Wood Pellet Mill
Ring die pellet mills are of vertical structure and they combine with the flat die pellet mills’ vertical feeding method. The original circle structure of ring die pellet press is specially designed for those wood materials like gum wood, palm which are hard to press. Because the proportion of the materials is light, so vertical feeding method is selected. In addition, due to the nice stability of circle structure ring die pellet mills, thus the design adopts combination of ring die and flat die. Ring die pellet mill has both advantages and disadvantages as below:
1.Large production, nice pellet forming shape and high density( 1-1.3%).
2. The roller and ring die are of balanced wear.
3.The main disadvantage is the relatively high power consumption if the output cannot meet target, the ring die costing relatively higher than flat die and will cracking if there are not proper in use, high amps needed to setup for ring die machine.
Flat Die Wood Pellet Mill
Compared with ring die wood pellet mills, the flat die pellet mills are applied to small and medium sized production which requires lower hourly output and the materials with large adhesive force.
Also, flat die pellet mill has its own advantages and disadvantages. On the whole, flat die pellet mill is of low energy consumption, greater mobility, so it is suitable for small and medium operation in enterprises and factories.
1. Pellet machine only need lower energy consumption motor compare to ring die machine.
2. Low wear and tear of roller, dies and bearings.
3. Flat die is cheaper than ring die and there are no common problem facing with ring die – cracking.
In a word, ring die wood pellet mills advantages are the flat die wood pellet mills disadvantages, and vice versa. You must consider all the factors that will limit your production carefully.
One Large Pellet Machine Vs Several Small Ones
Pellet machine can be divide into ring die pellet machine and flat die pellet machine. According to the size, they can be classified into large pellet machine and medium-small pellet machine. Commonly, ring die pellet machine has a large capacity while flat die pellet machine is with medium-small size and applicable for enterprise industries.
To start a pellet plant, people have to face the question of how to choose the ideal pellet machine equipment. Have you ever thought about whether to adopt one large pellet machine or several small pellet machines?
1) A large pellet machine can be expensive but with high production capacity. When there is need to change the die and roller, people can just stop it and do the changing work. Nevertheless, if something wrong happens, the pellet machine has to be stopped and thus the whole process will be suspended until the repair work has been done. Also, large pellet machine need experts like engineers and technician in production plants.
2)Small pellet machine is perfect for small scale production and enterprise. It can be cheap and convenient. However, several small pellet machines together can also do the same pelletizing work done by one large pellet machine. When changing die and roller, people have much work to do since there are several pellet machines. Fortunately, when one of the small pellet machines breaks down, the complete pelletizing process will not be paused since the other pellet machine can still keep working.
What you have to do is choose the right kind according to your practical requirement.
To start a pellet plant, people have to face the question of how to choose the ideal pellet machine equipment. Have you ever thought about whether to adopt one large pellet machine or several small pellet machines?
1) A large pellet machine can be expensive but with high production capacity. When there is need to change the die and roller, people can just stop it and do the changing work. Nevertheless, if something wrong happens, the pellet machine has to be stopped and thus the whole process will be suspended until the repair work has been done. Also, large pellet machine need experts like engineers and technician in production plants.
2)Small pellet machine is perfect for small scale production and enterprise. It can be cheap and convenient. However, several small pellet machines together can also do the same pelletizing work done by one large pellet machine. When changing die and roller, people have much work to do since there are several pellet machines. Fortunately, when one of the small pellet machines breaks down, the complete pelletizing process will not be paused since the other pellet machine can still keep working.
What you have to do is choose the right kind according to your practical requirement.
Select a Die
A die is a metal cylindrical shaped unit with holes through which meal is forced in order to produce pellets. When selecting a die one must consider the following criteria:
1. Best pellet quality(pellet hardness).
2. Highest capacity(hole count and shape).
3. Operational ease(can be handled easily).
4. Reduced plugging.
5.Longest die service life(total tons produced).
1. Best pellet quality(pellet hardness).
2. Highest capacity(hole count and shape).
3. Operational ease(can be handled easily).
4. Reduced plugging.
5.Longest die service life(total tons produced).
Pellet Machine Gearbox Maintenance
For a pellet machine, surely it equipped with a gearbox and all the manufacturer hope that the pellet machine can work for a long time, therefore beside of the correct operation of the pellet machine, maintenance of gearbox is necessary. For pellet mill, gearbox plays the role of adjusting the feeding speed and avoiding materials blockage. It is obvious that gearbox can largely affect pellets production, thus regular maintenance is quite important for the whole operation.
When doing the maintenance work, first you have to open the gearbox. Then you will see that the gearbox is submerged in oil. Do not underestimate the oil. Actually, it functions as a lubricant used to lubricate the gear teeth and keep smooth and easy operation. After a long period work, the oil should be changed. Normally, the oil should be changed per 5~6 months. Generally, Since a pellet machine consists of a lot of spare parts like die, roller, bearing, shaft and so on, a wide range of maintenance is especially crucial for the pellet machine to work smoothly. Do not greatly rely on buying new spare parts, because sometimes it does not guarantee a long time usage. Turn to put more emphasis on maintenance. Periodic maintenance and repair can prolong the life of the spare parts. Only if each spare part is with good performance, the pellet machine can keep an excellent and smooth operation.
When doing the maintenance work, first you have to open the gearbox. Then you will see that the gearbox is submerged in oil. Do not underestimate the oil. Actually, it functions as a lubricant used to lubricate the gear teeth and keep smooth and easy operation. After a long period work, the oil should be changed. Normally, the oil should be changed per 5~6 months. Generally, Since a pellet machine consists of a lot of spare parts like die, roller, bearing, shaft and so on, a wide range of maintenance is especially crucial for the pellet machine to work smoothly. Do not greatly rely on buying new spare parts, because sometimes it does not guarantee a long time usage. Turn to put more emphasis on maintenance. Periodic maintenance and repair can prolong the life of the spare parts. Only if each spare part is with good performance, the pellet machine can keep an excellent and smooth operation.
The Application of Wood Pellets in Industrial Boilers
Industrial boilers are used to provide heat. And coal serves as the main fuel for industrial boilers. Since burning of coal has caused huge pollution to the environment, measures have to be taken to handle this problem. At the moment, utilizing pellet mill to make biomass pellets as fuel has been adopted as the best method to relieve the situation.
According to a recent study, there are more than 500,000 industrial boilers in China. Since most domestic industrial boilers are burning with coal, their consumption of coal accounts for nearly 1/3 of that of the whole country's consumption. Pollution caused by burning coal is familiar to every one. As a result, more and more cities begin to set restriction on the use of coal-oriented industrial boilers. It is quite clear that industrial boilers must utilize clean energy as fuel to survive. Though oil, natural gas and electricity are clean energy, they do have limit. Thus using these resources to provide fuel for industrial boilers can not guarantee a sustainable development of energy resources.
With the prevailing of wood pellet mill to make biomass pellets as fuel, this problem can be definitely solved. Our country has abundant biomass resources. Forest and agriculture have a wide distribution throughout the country. Compared with coal, biomass pellets produced by pellet mill are easy to burn, and have low ash content. What is important is that they can be burned thoroughly and hardly contain sulfur. Perhaps the most important thing is that biomass pellets release hardly carbon dioxide thus helps to relieve greenhouse effect.
According to a recent study, there are more than 500,000 industrial boilers in China. Since most domestic industrial boilers are burning with coal, their consumption of coal accounts for nearly 1/3 of that of the whole country's consumption. Pollution caused by burning coal is familiar to every one. As a result, more and more cities begin to set restriction on the use of coal-oriented industrial boilers. It is quite clear that industrial boilers must utilize clean energy as fuel to survive. Though oil, natural gas and electricity are clean energy, they do have limit. Thus using these resources to provide fuel for industrial boilers can not guarantee a sustainable development of energy resources.
With the prevailing of wood pellet mill to make biomass pellets as fuel, this problem can be definitely solved. Our country has abundant biomass resources. Forest and agriculture have a wide distribution throughout the country. Compared with coal, biomass pellets produced by pellet mill are easy to burn, and have low ash content. What is important is that they can be burned thoroughly and hardly contain sulfur. Perhaps the most important thing is that biomass pellets release hardly carbon dioxide thus helps to relieve greenhouse effect.
How to Start a Wood Pellet Business
Wood pellet machine has gained more and more people's favor. Though a lot of people try to start a wood pellet business, some of them still do not know exactly the practical situation. What should be taken into consideration? A sufficient supply of raw materials, moisture content handling and selection of a rational location are all factors that should be highlighted.
Pellet machine is now widely used to make wood pellets. In essence, wood pellet machine is more appealing since the whole world is advocating energy conservation and environment protection. Wood pellets as fuel just conform to the slogan, so an increasing number of people want to start a business by producing wood pellets to meet the market demand and make profit. Then there comes the question of how to start a wood pellet business. What factors should be considered when establishing a wood pellet plant?
Firstly, a sufficient material supply is essential for running a pellet plant. To make wood pellets, raw materials like sawdust and woodchips need to be ready for use at any moment. For instance, a wood pellet plant with a capacity of 2T/H at least shall have 60T material in the stock daily. Thus continuous production can be guaranteed.
Secondly, moisture content of wood materials is rather important for pellet shaping. The ideal moisture content is 15%. If the moisture content is higher than 15%, a dryer should be equipped. When coming to the installation of a dryer, fuel has to be considered. Do manufacturers have to buy fuel for heat stove in the dryer? No, here wood pellets can in turn be used as the fuel to drive the dryer. Therefore, manufacturers do not have to worry about the fuel cost.
Lastly, a good location is also very important. A well-chosen location can save the production cost. That is to say, if the location is close to the supply area of raw materials, transportation cost can no doubt be largely saved. Above all, if there is a sudden lack of materials, the close distance can meet an urgent need.
Top 8 Issues You Should Consider
Nowadays, it is wise for you to develop a pellet mill business plant. According to our experience, there are some important aspects as following you should consider before starting up a pellet plant：
1. What is your target market, residential pellets, industrial pellets?
2. How to make the price position of your pellet mill?
3. What is the moisture content for your finished pellet products?
4. What kind of raw materials will be used for different pellet mills?
5. How many pellets do you plan to produce every month?
Pellet machine is now widely used to make wood pellets. In essence, wood pellet machine is more appealing since the whole world is advocating energy conservation and environment protection. Wood pellets as fuel just conform to the slogan, so an increasing number of people want to start a business by producing wood pellets to meet the market demand and make profit. Then there comes the question of how to start a wood pellet business. What factors should be considered when establishing a wood pellet plant?
Firstly, a sufficient material supply is essential for running a pellet plant. To make wood pellets, raw materials like sawdust and woodchips need to be ready for use at any moment. For instance, a wood pellet plant with a capacity of 2T/H at least shall have 60T material in the stock daily. Thus continuous production can be guaranteed.
Secondly, moisture content of wood materials is rather important for pellet shaping. The ideal moisture content is 15%. If the moisture content is higher than 15%, a dryer should be equipped. When coming to the installation of a dryer, fuel has to be considered. Do manufacturers have to buy fuel for heat stove in the dryer? No, here wood pellets can in turn be used as the fuel to drive the dryer. Therefore, manufacturers do not have to worry about the fuel cost.
Lastly, a good location is also very important. A well-chosen location can save the production cost. That is to say, if the location is close to the supply area of raw materials, transportation cost can no doubt be largely saved. Above all, if there is a sudden lack of materials, the close distance can meet an urgent need.
Top 8 Issues You Should Consider
Nowadays, it is wise for you to develop a pellet mill business plant. According to our experience, there are some important aspects as following you should consider before starting up a pellet plant：
1. What is your target market, residential pellets, industrial pellets?
2. How to make the price position of your pellet mill?
3. What is the moisture content for your finished pellet products?
4. What kind of raw materials will be used for different pellet mills?
5. How many pellets do you plan to produce every month?
