Solution for Beech Pellet Making

Solution for Beech Pellet Making

1. Introduction
2. Geographic distribution
3.Priorities of beech as biomass fuel
4. Fuel value of beech pellets
5. Beech pellets manufacturing

1. Introduction
Beech is a genus of deciduous trees, native to temperate Europe, Asia and North America. There are almost thirteen distinct species of this genus. The European beech is the most commonly cultivated, whose leaves are entirely or sparsely toothed, from 5-15cm long and 4-10cm broad. They are produced in spring shortly after the new leaves appear. The bark is smooth and light grey.
In terms of the use of beech wood, it is used extensively for furniture framing and carcass construction, flooring and engineering purposes, or in plywood and in household items as an ornamental tree. More importantly, beech wood is a very good firewood, easily split and burning for many hours with bright but calm flames.

Notes:
·1 ft (foot) = 0.3048 m
·1 lb = 0.4536 kg
·1 Btu (British thermal unit) = 1,055.06 J = 107.6 kpm = 2.931×10-4 kWh = 0.252 kcal = 778.16 ft lbf = 1.055×1010 ergs = 252 cal = 0.293 watt hour
The above table shows that most of the variations in net calorific value (CV) among species are caused by the amount of moisture content and wood density.

3.2 Wood density
A vital part of the viability of biomass as a fuel seems to be density. As hardwood species are generally denser than softwood species, a tonne of hardwood logs will occupy a smaller space than a tonne of softwood logs. Dense woods will burn for longer than less dense woods, which means you will need fewer ‘top ups’ to keep a log stove burning. If you measure wood by volume, you will generally receive more kilowatt hours (kWh) of heat from a cubic metre (m3) of hardwood than softwood. Given the above comparison, we can clearly see that the density of dry beech wood reach the top of 44.21b/ft3 among various wood species, which means beech wood density is suitable for the combustion process.

3.3 Moisture Content
The moisture content of wood has the most effect on CV of any of the variables. Not only does any water in the timber represent less fuel when buying by weight, but it is also necessary to evaporate away before the wood will burn, using some of the fuel energy reducing the net energy released as useful heat. The moisture content of beech is 43%, relatively lower than other wood species, serving as a great advantage over others as biomass fuel.
On top of CV, transportation cost also seems to have a lot of things with the amount of wood density and moisture content in biomass fuel. Transport of the fuel can contribute a large part of the cost, so the higher the density, the greater the weight and the less number of loads are required. This links in importantly with the moisture content which ideally will be fixed as low as possible so that each delivery contains the maximum amount of combustible fuel.Thereby, choosing beech as biomass fuel can reduce transportation cost. Furthermore, as for the combustion emissions, beech, as a kind of classic fuel wood species, is heavy, hard and compacted. It does follow that beech burns long producing a small amount of smoke.

4. Fuel value of beech pellets
Biomass, as a fuel, is the plant material that can be burnt to produce renewable heat or electricity. It utilises the sun’s energy stored during plant growth which is later released when it is burnt. Traditionally, wood logs have been the most commonly used as the biomass fuels, but other forms of wood have now increased in popularity such as pellets, chips and briquettes.

Given the above analysis, we can easily see the priorities of beech pellets over beech as biomass fuel. Through pelletization, beech pellets have a lower water content and higher calorific value.

With the modern technological process of pelleting process, a higher density and lower moisture content are reached, which allows a higher calorific value. Biopellet is reflected in lower fuel consumption and reduced waste during the heating season. When fossil fuels are burnt in air, they release the carbon they stored underground into the atmosphere as carbon dioxide (CO2). In contrast, when biomass fuels are burnt they release the carbon stored during growth, but reincorporate that carbon into the plant during the next growth cycle. The result is less additional carbon dioxide in the atmosphere with biomass fuels. Beech pellets contain no additives or binders of non-plant origin, so the ash content is very low. Also, beech pellets are standardized, which enables us to automate the entire fuel system and complete combustion quality.So, use beech pellets as biomass fuel, and you and your boiler will be grateful.

5. Beech pellets manufacturing
Pellets are small cylindrical pressed bodies. The raw material is composed of residual wood such as wood shavings or sawmill residuals left in their natural state. Typical wood pellet manufacturers are large pelleting mills.
The quality of the raw materials used has a decisive influence on the quality of wood pellets. In order to ensure the pellet quality required, scrupulous preparation and processing of the raw material are of extreme significance. The production of wood pellets therefore places great demands on the manufacturing process. How beech pellets are made in a pellet plant? Generally, it will go through the following procedures: