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What materials can be made into biomass pellets?
The raw material used for making fuel pellets is called biomass. Biomass is any living or recently dead material that can be used as fuel.There are a wide range of raw materials which can be made into biomass pellets, including wood sawdust, chips, shavings, branches, logs, palm EFB, palm fiber and stalks, straw, rice husk, peanut shell, sunflower seed shell, bamboo, bagasse, mushrooms residue, cotton residue, grass, cassava residue,etc.
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What is matrix for pellet mill?
It is a professional terminology referring to a key part of pellet mill. It can be seen as the mold of pelleting. The structure and quality of matrix largely affect the performance of pellet mill and quality of finished biomass pellets. Matrix is generally made from high hardness alloyed stainless steel. To ensure high finished degree and long service-life, matrix needs to be processed through vacuum heat treatment and precision finishing. Ring Die Pellet Mill is suitable for medium&large pellet production and industrial use.
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What are rollers for pellet mill?
Rollers work with matrix, constituting a die-roller assembly. There are two rollers(or three rollers) and one matrix mounted in the pelleting chamber. For Ring Die Pellet Mill, the rollers are subject to the matrix. During the pelletizing process, high pressure is produced between the matrix and rollers. When the raw materials are fed into the pelleting chamber, the rollers will press them towards the matrix. After the materials are forced through the matrix pore, pellets are gradually formed. It is necessary to adjust a suitable distance  between the rollers and matrix to achieve best pelleting effect.
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What is compression ratio of matrix for pellet mill?
Compression ratio is related with the diameter and length of matrix pore. It is a very key factor which affects the effects of pelleting. Different materials have different requirements on matrix design of thickness and pore size. A suitable compression ratio of matrix to your own materials will help you produce high density and output capacity of biomass pellets. There are two ways to calculate the compression ratio of matrix. One way is matrix pore diameter divided by matrix efficacious pore length; the other way is the pore diameter divided by efficacious pore length and relief area. According to our persistent research and feedback from our clients, we have sufficient experience on matrix design to process all kinds of biomass materials. For more information, please contact us freely.
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What is the structure of Ring Die Pellet Mill?
A Ring Die Pellet Mill has a ring shaped die, and a set of rollers. The die it positioned vertically, with the two rollers set within the die, applying force to the inner edge of the ring die. Due to the vertical roller and die position a motor is required to meter raw material into the centre of the ring.
Most Ring Die Pellet Mill operates with a driven ring and a stationary roller set. However there is a small selection of Ring Die Pellet Mill with a stationary die and rotating roller set. The advantage of gear-driven includes more positive driving force without the possible slipping of belt systems. The speed of the Pellet Press is determined by the raw material being processed, for example one proper speed may be suitable for grass and another speed proper for waste wood, etc.
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What is the working principle of Ring Die Pellet Mill?
Powder biomass materials enter into the place which is among ring die and pressing rollers. The running ring die drives pressing rollers to squeeze the powder material out of the small holes of ring die automatically. After the pelleting process, powder materials will be pressed(formed) into pellets. The cutter which is on the shell cuts the pellets into the size users want. The temperature of newly formed pellets is about 75~90℃ and humidity is 13% or so. Temperature drops to near room temperature after cooling. Ring die which is the most important part of Pellet Mill is easy to damage (wearing part). It directly influences the quality of finished pellets and capacity. A suitable compression ratio of ring die is very important for pelleting production when process different biomass materials.
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What is the advantage of Ring Die Pellet Mill?
Firstly Ring Die Pellet Mill does not suffer uneven roller and die wear as the inner and outer edge of the roller covers the same distance. For this reason Ring Die Pellet Mill is preferred for medium & large scale production as the costs of roller and die consumables are perceived to be lower. Ring Die Pellet Mill is also preferred for large-scale production as they are considered more energy efficient. All Ring Die Pellet Mill come complete with a conditioner and variable speed feeding to specially process variable biomass materials.
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What factors affect the service-life of matrix and rollers?
The life of matrix and roller are determined by several factors. Firstly the matrix metal will influence abrasive resistance and breakage resistance. Abrasive raw materials lead to shorter matrix and roller life. The roller gap also affects the life of consumables. If the rollers and matrix touch and there is metal-to-metal contact, this will increase wear, leading to a shorter life. Finally the speed of the pellet mill influences matrix and roller wear. With care hundreds of hours of use can be obtained.
 
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What main factors affect the pelleting production and quality of finished pellets?
1. Features of raw materials: species, volume, particle size, moisture
2. Compression ratio and smoothness of matrix
3. Feeding flow
4. Distance between matrix and rollers
5. Stable power supply
6. Lubricate bearings, matrix, rollers, etc
7. Operation and maintenance of equipment
 
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How to make biomass pellets?
This guide will follow the process step-by-step to produce quality fuel pellets. It states the equipment used at each stage. The step-by-step pelleting process is as follows:
 1. Size Reduction: Chippers/Shredders, Hammer Mills
 2. Material Transportation: Fans, Cyclone Separators and Screw/Belt Augers
 3. Drying: Rotary Drum Dryers, Air-flow Pipe Dryers
 4. Mixing: Batch/Drum Mixers( for mixed materials)
 5. Conditioning: Water and Steam Addition, Binders(option)
 6. Pellet Production: Pellet Mill
 7. Sieving: Removing Fines
 8. Cooling: Counter-flow Coolers
 9. Pellet Transportation: Bucket Elevators and Pellets Belt Conveyor
 10. Bagging and Storage: Bags, Sacks and Silos
 
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How to make pellet mill maintenance?
The equipment used in pellet production is exposed to high pressures and temperatures, extreme forces are placed on the equipment and proper maintenance can increase equipment life and reduce energy demand.
The pellet mill particularly has many bearings, which reach high temperatures during operation. Frequent checks of these bearings are required to maintain equipment performance and life.
Checking that the pellet mill can operate with the least resistance will keep energy demand to a minimum. For example checking that there is not a build up of material causing extra friction around the pellet mill matrix and rollers. Without these checks energy will be wasted on the extra friction placed on the matrix and rollers.
At the end of production it is important to clean the pellet mill matrix so production can easily be started again. If the raw material being processed is left in the matrix, as the matrix cools the material inside the matrix will also cool and the lignin will set. Once this has occurred it will be very hard to start production again and may require the matrix to be drilled out. The extent of the problem does depend on the material that was processed, and the matrix type and metal.
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Can you provide on-site installation,commissioning and training service?
Yes, we provide you proressional on-site installation, commissioning & training service at your local workshop. But the related costs are not included in the proposal. The related costs mainly include round-trip air ticket, Visa expense, hotel,meal & traffic expense at Buyer’s site, US Dollars 80 per technician per day,etc. The estimated time is about 30-40 days to finish all work.