颗粒设备：类型和主要生产商 Pelleting equipment: types and main producers
Nowadays renewable energy sources become more and more popular, as environmental issue arises. In this case, wood pellets, relatively new kind of fuel, are being used all over the world. Therefore, a number of entrepreneurs are starting their own pellet producing business. Consequently, they need to purchase appropriate equipment.
Stages of pellet making
As a rule, a complete pellet line is used in order to produce pellets. The technology of pellet making consists of following steps: crushing, screening, drying, pelletizing, cooling and packing.
So, different kinds of equipment are required to accomplish them. This equipment includes debarker or chipper, hammer mill, dryer, pellet mill (press), cooling and packing machines.
Units of pelleting equipment
Debarking machine is applied in order to peel and debark logs of wood. In this way, raw wood is being prepared for the further processing. There are two models of this kind of equipment: single roller and double roller debarking machine. The productiveness of the second one is higher: double roller debarking machine is able to process 70-100 tonnes of wood logs per day.
Hammer mill is applied in the process of pelleting in order to pulp wood chips. It makes it possible to turn logs of different size into smaller ones. Though hammer mill is able to process small branches and chips, it is mostly use to pulp big ones. In the hammer mill, material is being struck until it is small enough to be screened.
As fresh wood logs contain significant amount of moisture, they should be dried before processing. At the same time, moister evaporates too easily, which makes handled material shrunk, mildewed or spoiled in any other way. Consequently, pellets, made of such material, are of low quality. That is why drying machine is required to prepare material for the further stages of pelletizing process. As a rule, an appropriate moisture content should equate 8-15 per cent.
There two types of dryers: rotary sawdust (drum) drying machine and pipe sawdust dryer. The first one is a common type and is widely used in pellet plants. Its capacity varies from 2.5 to 36 tonnes. At the same time, the capacity of pipe sawdust dryer is not so high; however, the advantages of this type of dryer are low energy consumption and low cost.
Pellet mills, also known as pellet presses are applied at the main stage of pellet production. They are used to create pellets of previously processed raw material. The principle of pellet mill operation is opposite to hammer mill one. While hammer mill is used to pulp wood logs, pellet mill is applied to create larger, homogeneous mass.
There are many types of pellet mills, which can be divided into two main groups: large-scale and small-scale mills. At the same time, there two main types of large-scale mills, which include flat die and ring die mills. As a rule, flat die mills are applied to produce pellets of higher quality.
At the last stage of pellet production, cooling machine is applied. The use of this machine gives an opportunity to reduce the temperature of pellets from 80-90 degrees to the ambient temperature. It also reduces the content of moisture from 17-18 to 12-13 per cent.
Main producers of pelleting equipment
Nowadays the Ukrainian market of pelleting equipment is growing. A wide range of suppliers provides entrepreneurs with appropriate equipment. However, the main characteristic of domestic market is that it does not provide complete pellet lines. There is an opportunity to purchase separate units. Complete lines, which are sold in Ukraine, are imported.
In this case, it is necessary to mention those countries, which are producing pelleting equipment. First of all, it is Canada. This country was the first to produce both pelleting equipment and pellets. Beyond that, there are a number of countries, which also produce the same equipment. All of them possess significant forest areas.
This list includes USA, Russia, China, Sweden, and Germany. There are also several countries, which are producing cheaper equipment. Among them are Poland and Lithuania, for instance. All these countries provide world market with both complete pellet lines and separate units of pelleting equipment.
In summary, pellet market is rapidly growing. That is why a wide range of entrepreneurs starts their own pellet production. In this case, specially designed equipment is required. It consists of several units applied at the different stages of pellet production. At present, such countries as USA, Canada, Germany, Sweden, China, Russia and Lithuania remain the main producers of pelleting equipment.