How to make wood pellets

If you have many waste thing like grass, sawdust, wood log or any other organic materials, you don’t know how to deal with it or just through them away directly before. But it still needs to pay for money and energy for that process. Also it is big waster for materials. Then how about make pellet by yourself with a pellet mill? All you have to prepare is a pellet mill and enough raw materials. If you can make your own wood pellet, you can just enjoy the convenience, neatness and the lower cost than buy pellets from the market. Pellet energy as a renewable energy, it has been accepted by more and more people nowadays. In addition you can use it in the barbecues. Most pellets are made in bulk quantities by industrial pellet mills, but homeowners can also turn those organic materials into wood pellets. Then how to make pellet by pellet mill? Next, a simple method is introduced below. If you do it as the following step, you can get pellets at home with simple process:

The first step is to prepare the raw materials. Gather the wood to be used and reduce the size of the wood pieces. In theory, any kind of organic materials can be used to make pellets. But it is ensure that the length of the particle is no more than 2.5 cm and the proper particle size make the process smooth. Too large of the particle size can block the machine. If the raw material is over an inch in size it is usually chipped or shredded first, If small material like sawdust is being used this process can be skipped. When it is necessary, a hammer mill is used to reduce the size of the wood even further. Get the pieces as small as possible without turning it into sawdust.

Another factor that we should consider for is the moisture content of the materials. The moisture content is another key factor for making pellet; it can decide whether the pelletizing process is good or bad. Too dry or too wet of the materials can not make pellets or the finished pellets with bad quality. They are loose and easy to crush by hand pinch. So, there are some little tips that we can change the moisture content of the materials. It’s simple and easy. For the dry material, you can put some water into the material or spray water on them. The amount of the water content should be controlled until it is up to your moisture content requirement. For the wet materials, leave the wood in the sun to dry naturally, or place the wood pieces in an industrial slow heating oven until it is fried to the desired moisture level. Or you can use a dryer to dry the materials first if necessary.


 

Sometimes pouring it into the mixer will ensure all of the wood pieces become uniform and consistent in density, moisture and size. Make sure there is a rolling drum or an agitator working with the batch mixer. For the material which is difficult for pelletizing, you can add some bonding material for pelletizing. So the mixing process is necessary for this. Sometimes, the proportion of the ingredients of different materials decided the pellet quality. 
 

When you have enough materials with proper moisture content, the second step is to prepare the pellet mill. As for the choice of pellet mill, for home use, ZLSP200B model flat die pellet mill can meet your demand. You can pick up electric flat die pellet mill if there is easy access to electricity and the electric charge is cheap. Also you can use diesel engine motor as your choice. Then start the pellet mill in which you will make your pellets and wait a few minutes for the metal die inside to heat up. The heat will turn the small amount in the sawdust to steam. The steam in turn melts the lignin in the wood fibers and it becomes the bonding agent for the pellets. At the beginning, the feeding speed should be slow and the feeding amount should be less. After a few minutes of heat preparation, the machine is in normal operation. Improve the feeding speed and increase the feeding amount at this time, the machine is up to the biggest the production ability. During the production, inspect the operation of the pellet mill to ensue the product efficiency. 
 

Pouring it into the mixer will ensure all of the wood pieces become uniform and consistent in density, moisture and size. Make sure there is a rolling drum or an agitator working with the batch mixer. 

The third is cooling. The pellets just come out from the pellet machine are hot. It is necessary to cool the pellets completely. The cooling process makes the pellets with high density and hardness, which are fit for consumption. 

The last is to store the pellets in bags. Please take note that the pellet should be put in dry place to avoid of moisture. 
 

It seems that after you have pelletized the wood pellet you have done all the things you have to do. But there also have some important point you must to know, and have to follow to do.

Firstly, you should clean the die and rollers carefully. When you feed the machine with raw materials, there may have some hard impurities got stuck and if you don’t clean them out, it will be very harmful to the working station of the machine. Furthermore, you may not forget the bearings. The bearings will be working in a high temperature and high press, so maintain the bearings is very important.
 

Here have some advices and you can take based on your own situation. Before the mill begins to work, you can grand the die with the mixture of bran and oil. And the clearance between the template and pinch roller should be 0.1-0.3mm. Then, you should clean the bearing every 2-5 days and fill it up with grease that resist to high temperature. You also have to know that all maintenances thing must be done in the state of blackout. And the machine should be placed suitable and stable, because it is not good to the mill if you move it constantly.
 

The reason for the unshaped pellets: 

 During the process of making pellet by wood pellet mill, the finished products are out of shape with inadequate density sometimes, or the pellets are out of shape. 

There are two reasons for the out of shaped pellets. The first is the material. The second is the equipment of making pellet. Specific reasons for this are analyzed like below:

First is the moisture content of raw material. Moisture content of material is an important indicator for making pellet. Generally, the required moisture content is below 20%, but it is not absolute. Different materials have different requirements for moisture content, sawdust like pine, fir, eucalyptus, required moisture content is 13-17% for making pellet. The second is the different property of materials. Sawdust, paper scrap has different properties and different fibrous structures, so degree of difficulty for making pellet is diverse. The material which is rather difficult for compressing is palm. 
 

The third reason which affects the ratio of pelletizing is the proportion of mixture for mixing material. Compression ration is a parameter of wood pellet mill, which means length of die holes divide the holes diameter. The bigger the compression ratio is, the thicker the mould is. The longer the time of compressing is, the higher of the degree of pellet making is.  As long as the thick of mould is up to a certain degree, the sawdust is fit for make pellet, and the material is not confined to sawdust. Another factor for pellet mill is the clearance between die and compress rollers. It is understandable that too larger clearance is unable to make pellet. Adjusting clearance is a technical job. Customers are welcomed to consult our technicians.  
 

How to reduce the machine wearing of pellet mill: 

Wood pellet mill adopt the pattern of compressing feedstock into the holes of die through compress roller. Because there are no lubrication oil and binder during the whole process, the model is wearing seriously. Then what we should do to reduce the mechanical wear of wood pellet mill effectively? Please see below.Feedstock must be screen first and make pellet after removing iron. The speed of feeding is uniform and feedstock should not be piled up in the chamber.Feedstock should be crushed fully and sizes of pellets are in the scope which the pellet mill is suitable for making pellet at far as possible.The equipment should have powerful cooling system to low the working temperature of chamber, die and compress roller.
 

In recent years, due to the mineral energy shortage and consciousness of environmental protection, biomass briquette fuel is developed and strengthened day by day. As the key equipment of biomass briquette fuel, wood pellet mill play an important role in the reliability and stability of operation.

-------------------------------------------------------------------------------------------------------------------------------------