What Do We Understand by the Term Wood Pellet?
The term wood pellet refers to small cylindrical pieces of 10mm or 20mm long made of fine-ground essence of wood or bark. In other scenarios, they can come from compacted sawdust or similar industrial wastes generated from the manufacture and production of wood products. Furthermore, milling of cut lumber, construction, and preparation of furniture can create wood pellets. Other waste sources include palm kernels, treetops, discarded branches, coconut shells, empty and dried fruit bunches, etc.
A wood pellet can come in varying diameters ranging from 5mm to 10mm. Generally, such compressed biomass or organic matter serves as fuel. They get used by getting fed into a burner that helps generate the required form of energy.
Wood pellets have a smaller ratio or fraction of output energy compared to input energy. For that reason, they get used primarily and predominately in domestic households that do not require much of the resource. In such instances, their compact size and shape allow them to burn effectively and efficiently and work for gas stoves.
A wood pellet gets used in coal-powered stations and plants. It gets differentiated and distinguished based on its ash content, dimensions, heating value, and moisture. Overall, the applications of a wood pellet spread across a broad range. They can get used for cooking, residential, commercial, or power generation purposes.
What are the Various Advantages of Utilizing a Wood Pellet?
Utilizing a wood pellet for power and energy generation comes with different and diverse benefits. They have a broad range and scope of application and can get used in numerous sectors, areas, industries, and fields. A few advantages of wood pellet entail the following:
Wood pellets serve as an exceedingly cost-effective method of generating and supplying power. It is because they get made out of leftover material and pieces of wood. These wastes and remains get generated from other operations and processes such as woodcutting, sawing, polishing, or furniture creation.
In other words, wood pellets allow for a clean source of energy that reduces the overall associated waste content. That is why their prices and cost of production do not fluctuate, as is generally the case with other energy sources like fossil fuels.
Wood pellets serve as a sustainable and possibly renewable source of energy. They make for a system of low-carbon heating. In other words, they generate a minimal content of carbon dioxide and monoxide emission during the burning process. The reduction of the greenhouse gas release diminishes the harm and damage to the environment.
The burning of a wood pellet generates a specific carbon dioxide amount. It is almost equivalent to the content that a tree absorbs during its growth process. For that reason, there is mostly no adverse effect on the environment.
A wood pellet gets created using a pellet machine. Thus, it is typically compact and with small dimensions. It allows for their automatic input into the boiler without the help and interference of manual labor. In addition to that, the small size makes it effortless to store, carry, or transport the wood pellets in bulk. The compact nature also permits the pieces to possess a minimal amount or content of ash. It helps the pellets burn efficiently and effectively.
Renewable Source of Energy
Wood pellets get produced and create the waste and by-products of forest thinning and wood product manufacture. That is why these materials can continue to remain in production and serve as an energy source. It is possible as long as the other processes of their origin remain in practice. Hence, it can also get deemed a renewable and clean energy source.
What are the Steps to Make Wood Pellet?
The process of making wood pellets consists of detailed steps. They include the following:
Raw Material Gathering
The first step entails gathering raw materials such as sawdust, wood chips, or logs. They go into creating the wood pellets. The quantity or number would depend on the amount of final product necessary.
Since size matters for wood pellets, it is necessary to chip the pieces of 2.5cm or even smaller. It can get done using a wood chipper machine. Next, a hammer mill can get used to chop and grind the smaller pieces of the raw material into finer particles. This step is unnecessary for sawdust because it comes in a milled state.
The small wood particles need to get dried until their moisture level gets reduced to approximately 10-20%. It can get done naturally under the sun or in a drum drier machine.
Contaminants and other undesired particles like metal or stone can get mixed in the wood particles. They need to get removed to ensure a high burning efficiency of the pellets. A sieve with strainers and magnets generally does the job.
Vegetable Oil Addition
Generally, a small quantity of vegetable oil gets added to the small wood particles. It allows the raw materials to come and stick together effortlessly. It helps the tiny pieces remain bound together, influencing the texture and quality of the ultimate product.
The dried wood particles get added to a batch mixer and mixed for a pre-determined amount of time. It allows the materials to acquire uniformity and consistency in moisture, size, and density.
After passing through the batch mixer, the raw material then gets shaped. It acquires the standard and conventional dimensions of a wood pellet. It is possible to do so using a flat die mill. Otherwise, using the required amount of heat (maximum 170-190 °F) and casting them in dies also works.
The shaping process leaves the pellets moist and hot. It needs to get cooled for any further use. It can get done naturally by spreading them out or using a freezer.
Some wood pellets would come out deformed and unusable after the shaping process. They can get distinguished and separated using a sieve shaker with specified and desired mesh sizes.