Briquettes – universal fuel

In times of growing environmental awareness, more and more people consciously give up using fossil fuels in their households. However, this does not have to mean any kind of sacrifice. There are many ecological alternatives to coal or gas. One such material is efficient and easy to produce briquette – that is compressed fuel in the form of blocks, produced from biomass, that is, waste of natural origin.

Let us take a closer look at it.

Types of briquettes

At the outset, it is worth noting that we distinguish several types of briquettes. The criterion for this division is primarily the material from which a given type is produced:

Wood briquettes

These briquettes are produced from sawdust, wood chips or other wood waste. They are relatively ecological because they produce a small amount of smoke and ash. The calorific value of wood briquettes ranges from 18 to 22 MJ/kg, which makes them an ideal solution for domestic stoves, fireplaces and biomass heaters.

Biomass briquettes

Produced from various plant waste, such as sunflower husks, straw or olive pomace. The calorific value of these briquettes usually amounts to 15–20 MJ/kg, and their main advantage is the fact that they are produced from raw materials intended for disposal. Burning biomass has a smaller impact on the environment than, for example, the use of fossil fuels, because the carbon dioxide emitted during combustion is balanced by the CO2 that plants absorb in the process of photosynthesis.

Briquettes from paper waste

A separate subcategory is briquettes produced from paper waste and waste paper. Although they are less popular than other types, they are used in some industrial furnaces and boilers. Their calorific value is lower than in the case of biomass or wood. Nevertheless, they are an ecological alternative that helps reduce the amount of waste.

Also check our other article: Briquette vs coal – which fuel to choose

Briquette production process

Briquette production is a relatively simple process, however requiring appropriate equipment facilities in the form of a briquetting machine.

It can be summarized in a few simple steps:

Raw material preparation

Raw materials used for briquette production, such as wood or biomass, must first be properly prepared. This often includes their preliminary shredding (for this we will need a shredder or wood chipper), and then drying. The lower the moisture content of the raw material, the more efficient the combustion of the briquettes produced from it will be.

Briquetting

After preparing the raw material, the material is fed into the briquetting machine. There, the briquetting process takes place, that is pressing the raw material under high pressure. As a result, the raw material obtains a compact, dense form. The loose initial material is formed into compact blocks with sizes depending on the parameters of the briquetting machine.

Cooling and packaging

The finished briquettes are cooled and then, if intended for sale,  packed in a way that allows for their easy transport and storage. Many briquettes are packed in bags of a specified weight, which facilitates their distribution on the market.

An important advantage of briquette production is the possibility of using waste that could otherwise end up in landfills. Thanks to this, the briquette production process is also beneficial from the point of view of environmental protection, because it allows the reuse of materials that might otherwise be considered waste.

Combustion parameters of briquettes

The combustion efficiency of briquettes depends on their calorific value, moisture content and density. A high calorific value means a greater amount of energy obtained from a unit of fuel mass. Briquettes, due to their density and low moisture content (compared to e.g. loose wood), burn efficiently and generate a large amount of heat.

Approximate calorific values for different briquettes are as follows:

• Wood briquettes: 18–22 MJ/kg
• Biomass briquettes: 15–20 MJ/kg
• Waste paper briquette: 14–18 MJ/kg

Applications of briquettes

Briquettes are widely used both in households and in industry. They can successfully be used to fire domestic boilers and generate heat for one's own home. Unlike pellets, briquettes require less specialized heating equipment. Briquettes can even be burned in a fireplace or a so-called “goat” stove. 

Briquettes will also prove useful in industry. Their combustion can generate heat and energy for production halls and all kinds of plants. An interesting example of such application can be all kinds of paper mills. In such a situation, a briquette created from paper scraps can serve as fuel to generate electricity, steam or heat necessary for further paper production.

Summary

Briquettes are a versatile, efficient and ecological fuel that is widely used in domestic heating systems, industry and energy production. Thanks to the variety of briquette types, they can be adapted to different user needs. Their production process is relatively simple, and their combustion is efficient and more ecological than traditional fossil fuels. Briquettes also do not require extensive equipment facilities in the form of specialized boilers or burners (as is the case with, for example,  pellets).

However, their greatest advantage seems to be the fact that any household generating significant amounts of bio-waste can, with relatively little input, undertake the independent production of this fuel and in this way become independent from external suppliers.