October 30, 2020

The Thermal Conversion Of Biomass To Activated Carbon (And Everything In Between)

The biomass industry has seen steady growth the past few years, as nations around the globe continue to shift focus toward more renewable energy sources.https://yrdcarbon.com

And while biomass offers direct uses in itself, it can also be converted to a number of carbon products, all of which are created through thermal processing in an indirect rotary kiln, also often referred to as a pyrolysis kiln.

Biomass offers significant potential to improve the world around us through a range of products and applications.

Biomass begins its journey as organic matter, the source of which can vary significantly: animal remains and by-products, plants, forest product residuals, and even residuals leftover from the agricultural industry can all serve as a source of biomass.

Biomass alone can be utilized as a source of energy, either through burning it directly as a source of heat, or by converting it into a biofuel for use as an alternative energy source. Similarly, it can be converted into biomass pellets for use as an energy source.

In addition to these uses, biomass can be upgraded into several higher value products.

One common higher value carbon product produced from biomass is biocoal. Biocoal is a form of synthetic or man made coal that can take the place of, or be co-fired with fossil-fuel based coal products in energy plants.

To produce biocoal, biomass is torrefied in an inert (oxygen-free) environment. This is typically carried out using an indirect rotary kiln (also referred to as a calciner).

Dried wood biomass is processed at around 500 – 800º F for a specific amount of time in order to upgrade it to biocoal. This pyrolysis process further reduces the moisture content, upgrades the energy value, and causes the material to become hydrophobic, meaning it will not absorb moisture from the air like lower-grade biomass products might.

Biochar is also a product upgraded from biomass. Biochar is similar to biocoal, but is made with a completely different intention; biochar is utilized as a soil amendment.

The production of biochar is the same as biocoal, with dried biomass being processed in a kiln at around 500 – 800º F for a set amount of time.

Interest in biochar has surged over the past few years, due to it’s restorative capabilities in soil, as well as the potential for it to sequester carbon in soil, reducing greenhouse gases. Furthermore, biochar can also be used in soil remediation applications.

At temperatures between 1,000 – 1,200º F, the biochar or biocoal product transitions to a pure carbon material through carbonization. At these temperatures, 75 – 90% of the volatile components existing in the material are removed.

Pure carbon has few applications for which it can be used, though it can be used as a filler in plastics. activated carbon pellets free samples

At temperatures between 1750 – 1850º F, injecting air, carbon dioxide, or steam into the pure carbon causes activation. This removes any remaining volatile components and through endothermic reaction, converts the carbon to what is known as activated carbon – the highest value product that can be created from biomass.

Activated carbon is a versatile material used throughout a number of industries as a powerful adsorbent. It aids in air pollution control, contaminated water treatment, and more.

Various grades and forms of activated carbon can be produced, each suited to different applications.