Wood Pellets Biomass Fuel and Pellet Stoves Boilers » Making Pellets

Wood Pellet Production Video

admin — Fri, 13 Nov 2009 12:40:45 +0000

I’ve recently come across a really nice video of a wood pellet plant in the US. The video contains quite a bit of detail on their operation. They are currently producing premium pellets, and aiming for the 0.5-1% ash bracket. However they do wish to move into producing a more standard pellet in the future. The standard pellet will produce higher ash content, however it will be cheaper to produce. Currently there is a lot of wood residue, which cannot be processed into fuel pellets because it is not suitable to produce a premium grade of pellet. However many pellet stoves and boilers can only burn a premium standard of pellet fuel. This is where is it an advantage to purchase a more fuel flexible pellet stove or boiler to be able to use a cheaper standard pellet, instead of only premium pellets.

Pellet Mill from The Wild Center on Vimeo.

The video shows their process from start to finish. They have chips delivered by truck, and they go through the first hammer mill. These chips then get dried to probably around 10% moisture content, and then they go through a second hammer mill to reduce the particles ready for the pellet mill. They are using a series of ring die pellet mills to produce the pellets, which are then cooled and sent to a large storage silo.

For more information on wood pellet mills, please Click Here

Pellet Mill Cooking

admin — Fri, 23 Jan 2009 13:45:28 +0000

From various information that I have read on the Internet, and questions I get asked, for example ‘how does a pellet mill work’ and ‘what will and will not work in the mill’ it is clear there is a lack of accurate information on how the process works. However another reason is, there are no simple answers to those questions. There are only general rules for example mill moisture content tolerances. The best way that I’ve found to describe the process is to describe it as cooking, and the pellet mill is simply your oven.

Ingredient Percentages
To make a cake you follow a set of ingredients with different percentages. The pellet mill is very similar; you need a certain percentage of water, not too much and not too little. You also need a certain percentage of binding ingredients. There maybe sufficient naturally accruing lignin, or supplementary binders maybe required.

Ingredient Consistency
Once you have your ingredients to make the cake, you mix the ingredients to produce a uniform mix to place in the baking tin. Again the pellet mill is very similar. For the pellet mill to produce uniform consistent quality pellets, your raw material must have consistent uniform qualities.

Pellet Mill Temperature
When cooking and baking you have to get the oven up to temperature before you put the cake in. The pellet mill also has to get up to temperature before quality pellets are produced.

Therefore pellet production, particularly on a low cost small scale is a skilled process. As a professional cook learns through experience and trial and error of ingredients to produce the correct cake, the pellet producer will too. Trying different percentages of moisture and other aspects in the mill to achieve the best quality pellet.

To aid our customers through this learning process and aid their education, through the PelHeat website we will provide a members section. The members section will have articles, pictures and videos on tips how to process different raw materials, improve mill productivity, improve quality and machine maintenance.

The PelHeat Mobile Pelletizer can process resources including wood into fuel pellets. If you would be interested in registering your interest in the PelHeat Mobile Pelletizer and receiving updates on our progress and informed when the pelletizer is on sale please send us an email to :

Contact @ PelHeat . Com

For more information please visit:

www.PelHeat.com

Thank you for your interest

History of the Pellet Mill

admin — Mon, 19 Jan 2009 17:04:26 +0000

Pellet mills have existed for over a century and have been used for the compression of various raw materials. The most popular use of a mill was for producing animal feed. The earliest unit was a flat die mill, with the development of the first ring die mill in the 1930’s.

Using a pellet mill to produce a fuel is by no means a new idea; in the 1970’s companies using their mill to produce feed pellets experimented and produced wood pellets. Pellet fuel has only been seen as a serious fuel since the mid 1990’s due to previously cheap and stable fossil fuel prices.

Therefore more mills are been produced and mill research and development continues to improve mill quality and reduce mill power demands.

A pellet mill is a very flexible piece of equipment, by adjusting parameters various resources can be used. Currently the emphasis is on using the mill for premium wood pellets as a fuel, however there are many more biomass materials, which can be used.

The PelHeat Mobile Pelletizer can upgrade various biomass resources into fuel. If you would be interested in registering your interest in the PelHeat Mobile Pelletizer and receiving updates on our progress and informed when the pelletizer is on sale please send us an email to :

Contact @ PelHeat . Com

For more information please visit:

www.PelHeat.com

Thank you for your interest

Any Wood Will Do?

admin — Sun, 18 Jan 2009 18:44:54 +0000

The advantage of small-scale pellet production is the possibility of using various different types of resources to produce fuel pellets; this can include using waste resources. With wood for example there is not only lots of virgin waste wood resources available, for example in the form of a tree surgeons wood chips but also in other forms of processed wood waste. Processed wood waste could be in the form of waste building materials, MDF, particleboard, fibreboard, chipboard and so on. I know many people are considering these waste materials for fuel and for fuel pellets, but certain aspects need to be considered first.

Contamination

As with any raw material used in pellet production, material contamination is very important. Stones or pieces of metal (nails) could cause serious damage to the hammer mill and pellet mill. Dealing with certain waste wood building material the risks of contamination is quite high.

Pellet Mill Issues

With regards to processed wood products, for example MFD and chipboard, resins and glues are used in their production. When processing a material such as this there are two possibilities when processing under the heat and pressure of a pellet mill. The glues or resigns may aid pellet binding and help lubricate the process, or the more likely event that they will cause the material to block the die.

Burning Issues

Processed and contaminated wood waste is not something, which should be burned without major considerations. Paints, glues and resigns when burnt release all kinds of particles and other things. Potentially causing damage to the burner, the owners, the environment and the atmosphere.

On a small scale using these material is a risky business. Due to the potential risks we will only recommend virgin and un-processed biomass resources to be used in the PelHeat Mobile Pelletizer.

For more information please visit:

www.PelHeat.com

The PelHeat Mobile Pelletizer can upgrade various biomass resources into fuel pellets including wood pellets. If you would be interested in registering your interest in the PelHeat Mobile Pelletizer and receiving updates on our progress and informed when the pelletizer is on sale please send us an email to :

Contact @ PelHeat . Com

Thank you for your interest

Manure Fuel Pellets

admin — Sat, 17 Jan 2009 19:34:54 +0000

I receive quite a few requests asking if it would be possible for the PelHeat Mobile Pelletizer to process manure, for example chicken manure or horse manure and produce fuel pellets.

Fuel Potential

Manure as a fuel is well known is developing countries; manure produces a high heat value and produces relatively little ash. In many cases in the western world chicken manure and horse manure removal can be quite a large issue, and has to be handled in a certain manor. Converting manure into fuel pellets would make sense, for example chicken factories could use the waste chicken bedding to be upgraded into pellets to heat the chicken sheds, which are currently heated via oil or gas. This would solve two issues for the farmer, and drastically reduce waste removal and fuel costs.

Potential Issues

It is possible the manure could harbour potentially harmful pathogens, which could be released during the process of upgrading the manure into pellets. During the pellet production process the manure would go through size reduction and then be exposed to high temperatures during the pellet formation. Due to the potential risks for the operator of the unit, we are not willing to recommend processing such materials until we have evidence to prove the operator is not at risk. Once the first units are on the market we intend to look further at the manure issue, and modify the unit to kill any possible pathogens.

For more information please visit:

www.PelHeat.com

Contact @ PelHeat . Com

Thank you for your interest

Pellet Binders and Lubricants

admin — Tue, 18 Nov 2008 12:07:43 +0000

Pellet binders and lubricants is a complicated area of pellet production, and one that many people find confusing. Whether a binder or lubricant is required depends on several factors, and is something which is gained through experience.

Pellet binders are additives to the pellet production process, which help to increase pellet quality, productivity and reduce fines loses. All biomass is cellulosic material, and contains a certain percentage of natural binder lignin. Most cellulosic material can be pelletized without using additional binders, however some materials do require an additional binder.

For lignin to work as a binder, sufficient heat needs to be generated in the pellet mill, to essentially melt the lignin. Now to obtain the heat required in the pellet mill, the correct pressure must be reached. Several factors are needed to reach the correct pressure; two of the most important factors are roller height and moisture percentage. If the roller height is too low or too high, or the moisture percentage is too low or too high, the critical pressure point required to melt lignin cannot be reached. In large-scale pellet production they use high temperature steam to begin the melting process. So many materials can be pelletized without binders, however it does require good process control to obtain the correct pressure.

Binders can be used to make the process easier, removing the need for precise pressure control. Pellet binders can also increase the efficiency and productivity of the pellet mill, reducing energy demands. The lubricating factor of the binder increases productivity and reduces the chances of die blockages. The decision that arises is, does increased pellet quality and productivity justify the additional cost of the pellet binder. Again the answer to this question is gained through experience with the raw material.

There are many different types of commercially available pellet binders on market, however there are waste resources from other industries which can also be used, for example dried distiller’s grain and rape cake.

If you would like to register your interest in the PelHeat Mobile Pelletizer please contact us at:

Contact @ PelHeat . com

Thank you for your interest

www.pelheat.com

Pellet Quality and Consistency

admin — Mon, 17 Nov 2008 12:04:42 +0000

The aim in pellet production is always to produce the best quality pellets, with the highest productivity possible. A quality pellet will be dense, shiny and break cleanly. Will every pellet out of the pellet mill look exactly the same, with the same density and surface shine, the answer, probably not.

The reasons for differences in pellet quality through the batch are to do with raw material consistency. Simply, to produce a consistent batch of every pellet being of the highest quality, the raw material going into the pellet mill must also be of the same consistent quality. Therefore raw material consistency with regards to the correct moisture content and binding qualities are directly related to the consistency of the pellet batch.

The question then is how important is pellet quality consistency, and this depends on the end use. For this example if we look at fuel pellets instead of other biomass pellet uses, it depends what type of burner the pellets are used in. For example the smaller the pellet burner, for example a small stove compared to a larger boiler, pellet quality consistency is of greater importance. Also the type of burn pot used affects how important pellet quality is. Use the search on the blog to find entries on different stoves, boiler and burn pots.

So sufficient pellet quality is judged on the end use requirements, but how can pellet quality be judged? Well the target quality pellet is dense, smooth, shiny and breaks cleanly with a sharp edge. So if a pellet does not have all of these features, what are the core requirements? A lower quality pellet still needs to serve a purpose; therefore it should hold its shape and take small forces without breaking. Lower quality pellets will not break as cleanly, however if the pellet under breaking completely crumbles this is not acceptable. Surface shine is an instant indication of a quality pellet, and lower quality pellets may not shine, however they may still be of sufficient quality.

Every batch of pellets will have a percentage of lower quality pellets. The question is, is the percentage of lower quality pellets acceptable or not, and this answer will be gained through experience. Generally though, the highest pellet quality should always be the target, as this gives lower maintenance and higher thermal efficiency.

If you would like to register your interest in the PelHeat Mobile Pelletizer please contact us at:

Contact @ PelHeat . com

Thank you for your interest

www.pelheat.com

Reed Pellets

admin — Fri, 07 Nov 2008 13:23:28 +0000

We were asked to perform a test for a potential customer on water reeds. Due to the nature of their project the water reeds must be maintained and cut thee times a year.

Once the reeds have been air dried, they are then used for thatched roofing, one of the oldest roofing methods, and very efficient at keeping heat in by the way.

However there is roughly 30% of reed waste left over after the reed has been sent for roofing purposes, and we were asked to do a trial on the material to see if we could produce some pellets for use in boilers and stoves. The pictures below are of the 6mm reed pellets we produced.

After a few tests and experiments we found the reed produced their best pellets between 13-15% moisture. The pellets were produced with no additional binder, and are hard, shiny and dense. We hope to produce some more reed pellets in the future and conduct some test burns in our pellet boiler.

If you would like to register your interest in the PelHeat Mobile Pelletizer please contact us at:

Contact @ PelHeat . com

Thank you for your interest

www.pelheat.com

Moisture Meter

admin — Wed, 05 Nov 2008 17:15:17 +0000

In pellet production moisture plays an integral role, too much or too little moisture and quality pellets cannot form. Sufficient moisture is required to build sufficient pressure, to generate heat to release the natural lignin from within the material to bind the material together to create a firm dense pellet.

Most materials to produce a quality pellet prefer a moisture percentage between 10-15%; in many cases it appears to be 13-15%. The dry weight test, which I featured a video on, is a very accurate test, however it’s quite slow. I have been looking at various moisture meters for many months, and the problem has always been finding a meter suitable to the wide variety of milled materials used in pellet production, and being able to test the finished pellets. For the finished pellets to burn efficiently, ideally they should have moisture below 10%.

A new moisture meter has come on to the market made by Doser, this unit has been specifically designed to measure wood chip, cereals, other granules and pellets. This wide range of abilities makes the unit ideal for pellet production.

Model Number: DS18-CM1801

If you would like to register your interest in the PelHeat Mobile Pelletizer please contact us at:

Contact @ PelHeat . com

Thank you for your interest

www.pelheat.com

Raw Material Contamination

admin — Tue, 21 Oct 2008 16:49:50 +0000

When sourcing raw material for pellet production, care must be taken to not process contaminated materials. Contamination in the form of solid particles of stone or metal is the most serious.

Hammer Mill Contamination

When processing materials with contamination such as stones and metal such as nails, need to be taken seriously. For example processing wood chip form waste wood such as old building timber, this may contain nails. The hammer mill runs at high speeds around 4000RPM, if a nail enters the hammer mill this can be dangerous for several reasons. As the nail comes into the contact with the hammers sparks will be made, if the material is relatively dry this could start a fire in the hammer mill. The nail may also be thrown back out of the hammer mill at the user at very high speeds. Contamination from stones gives similar results.

Pellet Mill Contamination

The stones or metal may pass through the hammer mill unnoticed, not starting a fire. However when stones or metal enter a pellet mill, this can seriously damage the pellet mill. The rollers are set a fixed distance over the die plate, usually 1mm. This is a very small clearance and provides no room for a stone or piece of metal to pass under. If the stone or metal was caught between the roller and die, this could either seriously damage the roller and die or break teeth off the bevel gears that run the pellet mill.

Material contamination should be taken seriously and efforts should be made to source uncontaminated materials for the safety of the user and machine.

If you would like to register your interest in the PelHeat Mobile Pelletizer please contact us at:

Contact @ PelHeat . com

Thank you for your interest