How are Traeger BBQ Wood Pellets Made?

What are Traeger Wood Pellets?

Hi, I’m Chris. I started back in 2007.

Traeger Pellet Grills LLC was started in 1985 by Joe Traeger, and is based in Salt Lake City, Utah, USA. Wood pellet grills and BBQ wood pellets have become a niche of the wood fuel industry. However, while wood pellets over the previous decades have been a very small niche in the BBQ industry, it’s grown considerably. Where previously Traeger Pellet Grills were only available in the US and Canada they are now even sold in Europe. Besides producing pellet grills, Traeger actually produces their own brand of BBQ wood pellets of various different flavours.

Traeger Wood Pellet Grill
Traeger Wood Pellet BBQ Grills are one of the most popular wood pellet grills around the world. – Image:

While it’s generally acknowledged that cooking with charcoal produces improved flavoured food over gas, the cooking process is harder to control. BBQ wood pellet grills use a hopper and feed auger in a similar fashion to pellet stoves and boilers. Therefore the temperature of the cooking process can be precisely controlled.

How Traeger Wood Pellets are made?

While I have my main post on how wood pellets are made, I thought I would share with you Traeger’s own video on their process. It’s slightly different from the ‘normal’ wood pellet production process. However, most of the equipment is the same. Check out the video below to watch how Traeger wood pellets are made. Please note it takes 40 seconds to get through the promotion before they start to show the actual pellet manufacturing process.

At 40 seconds into the video you start to the see the process of how Traeger Wood Pellets are made

Raw Materials and Preparation

Making Traeger Wood Pellets
Traeger has to deal with a range of woody biomass materials to produce their BBQ wood pellets.

One area where Traeger has a different (and generally) more difficult pellet manufacturing process is dealing with a wide range of raw materials. They produce BBQ wood pellets from Hickory, Mesquite, Apple, Cherry, Oak, Alder, Pecan, Maple and various other blends. That’s a lot of raw material management to take care off. Traeger appears to be making wood pellets from whole logs.

Normally with a typical fuel pellet plant, you prepare a standard raw material, typically either softwood or hardwood. You then set up the plant to deal with that particular raw material. That can involve setting up the hammer mill with a certain sized screen. It can also involve setting the dryer to a certain rotation speed. Finally, it can involve using a specific die at the right compression in the pellet mill. With Traeger, they have multiple different wood species to deal with in separate batches.

Now, when you watch the video if you pay close atension you will notice the narrator make an important point. He states that the other wood species are mixed with alder or oak. Therefore, with an applewood pellet blend its not 100% applewood. It’s not clear what percentage of the mixture used to make the BBQ wood pellets is applewood. I don’t believe they are mixing the raw materials together before the wood pellets are produced. More than likely they are mixing the separate batches of wood pellets together before packaging.

Size Reduction via the Hammer Mill

Hammer mill feed hopper
A front loader places the woody biomass into the hammer mill feed trough.

The first part of the Traeger wood pellet plant appears to be their hammer mill trough feed hopper. A screw of belt conveyor will then take this material at a controlled rate into the hammer mill. The hammer mill is likely fitted with a 5mm screen, as Traeger produce 6mm BBQ wood pellets. The material produced from the hammer mill is now a small consistent particle size suitable for the pellet mill. However, the raw material first needs to be dried down to the perfect moisture content.

Drying the wood before the Pellet Mill

Large rotary dryer
Traeger are using large rotary dryers to reduce the materials moisture content ready for the pellet mill.

If you have read my main page on how to make wood pellets you will know that getting the moisture content right is very important. As this is a large scale pellet plant Trager is using a large rotary dryer. The video itself does not actually demonstrate the order of their process correctly, showing images of the pellet mill before images of this rotary dryer.

You have to set up the rotation speed of the dryer to suit the raw material moisture content of the wood your processing. In general, the optimum moisture content for the pellet mill is 12%. As stated at the start of this post, Traeger has significant challenges due to the wide range of woody biomass materials they have to process. Depending on how long the material has been sat in the yard will impact on the starting moisture content. Testing the raw material and changing the dryer rotation speed could be very labour intensive. Furthermore, if you get it wrong it could disrupt the whole process. Even leading to a pellet mill die blockage.

While it’s not shown in the video I would imagine they have inline infra-red moisture meters. These constantly monitor the raw material as it enters the rotary dryer. The computer can then adjust the speed of the dryer to suit the wide range of different raw materials this plant has to process. While these inline infra-red moisture meters can be very expensive, on a pellet plant such as this they can be invaluable. Plus, you also have to remember these are BBQ wood pellets. On a value per weight basis, BBQ wood pellets produce the most profit by far of any other wood pellets.

The Larger Ring Die Pellet Mill

Large ring die pellet mill
Traeger use a large ring die pellet mill and food-grade soybean oil to aid the process.

Where the Traeger wood pellet process differs from standard fuel pellet production is in the use of food-grade soybean oil. Vegetable oil is often fed into pellet mills via drip feed or peristaltic pumps to reduce the pressure within the die and avoid die blockages. However, too much oil will reduce the compression of the wood pellet to a point where it doesn’t form to a sufficient density.

The Traeger wood pellets are made with food-grade soybean oil as these are BBQ pellets. The smoke from Traeger wood pellets penetrates the food to produce the delicate wood smoke flavours. Therefore using a food-grade oil in this instance is good practice. For standard wood pellet production, it’s common to use other pellet binders.

Ring Die or Flat Die Pellet Mill?

Ring Die Pellet Mill
A typical design of ring die pellet mill

Traeger has chosen to use ring die pellet mills over flat die machines. The advantages are increased roller and die life, more consistent pellet quality and a lower power input per ton of pellets produced. The material is metered into the centre of the ring die pellet mill, where the die is mounted vertically.

Two rollers are located on the inside of the die, the pellets are produced on the outer edge of the die. The rollers are not actually set against the surface of the die. There should be no metal to metal contact. The rollers are set with a small gap, typically 1mm to create a carpet of material against the die. This gap improves pellet quality and also increases roller and die service life.

Cooling the Traeger BBQ Wood Pellets and Packaging

Wood Pellet Packaging

After the wood pellets leave the pellet mill they first need to be cooled before packaging. The wood pellets leave the pellet mill hot. As the wood pellets still contain between 7-10% moisture if they are placed in a plastic bag hot they will sweat and break apart. Therefore it’s very important to let the wood pellets cool before they are packaged up. Large counter flow coolers will be used where a fan pulls air through the pellets and vents to the outside.

In the screenshot from the video above you can see the operator fill standard 20lb bags. This is a typical bag size also used for fuel pellets. However, you can also source Traeger BBQ wood pellets and other brands in small pouch bags. These can be purchased as part of a set to try and range of BBQ wood pellets in a smoke pot.

Conclusions on How Traeger Wood Pellets are Made

Generally, the process is very similar to how I describe the pellet production process in my other posts. The main difference with Traeger wood pellets is the wide range of different species they have to deal with. Furthermore, they are producing a food-grade product. As Traeger have to source a wide range of wood species, the logistics of getting those different raw materials to their pellet plant in sufficient volumes must be a challenge.

However, it’s important to remember, BBQ wood pellets are very profitable. Therefore while it will take more time and effort, and their raw material will cost more, the results are worth it. I must admit as well, after I used BBQ wood pellets for the first time, food produced on my gas BBQ just seemed a bit boring!

How are Torrefied Wood Pellets made?

Hi, I’m Chris. I started back in 2007.

Before we look at how torrefied wood pellets are made, we need to discuss what they actually are. The best way to think about torrefied wood pellets is as the next evolution of pellet fuel. They are superior in every aspect to standard wood pellets and address some of the current issues with pellet fuels. With torrefied wood pellets the same general process of how to make wood pellets applies. However, there are some important differences which I’ll discuss below.

Torrefied Wood Pellets
So the first thing you will notice are that torrefied wood pellets are black

Torrefied biomass is known by several other names such as ‘man-made coal’ and ‘bio-coal’. That’s because that’s basically what torrefied wood pellets are, man-made coal. Now the difference between bio-coal and fossil fuel based coal is the age of the carbon.

When we burn fossil fuel based coal we are releasing carbon that has been out of the carbon cycle for millions of years. Therefore increasing the carbon dioxide within our atmosphere. However torrefied wood was part of the current carbon cycle, therefore burning this material only returns the same carbon to the existing cycle. The new biomass grown as its replacement will absorb those carbon emissions and the cycle begins again. This is why the process is referred to as been carbon neutral.

How Torrefied Wood Pellets are Made

The video below from Blackwood Technology gives a good overview of their torrefied wood pellet process. The wood pellet making process starts off very similar to the standard process. Virgin wood is first chipped, then processed through a hammer mill. The wood is then dried down from 50% moisture to below 15% with a standard biomass dryer. For normal wood pellet production once below 15% moisture, the material is ready for the pellet mill. However, this is where the process differs from a normal wood pellet plant.

Blackwood Technology describe their torrefied wood pellet process.

To produce torrefied wood pellets the biomass is then heated to around 300 degrees Celsius in a zero oxygen environment so combustion does not take place. After around 30 minutes this produces a much purer form of carbon fuel, with very low moisture content. The torrefied wood is then processed via a series of ring die pellet mills to produce the torrefied wood pellets.

What are the Benefits of Torrefied Wood Pellet?

Standard wood pellets absorb moisture very easily, hence why they are such a good product for horse bedding. Torrefied wood pellets repel moisture, therefore addressing one of the key issues with current wood pellet fuel. Torrefied wood pellets also produce no smell, no visible smoke and contain a much higher energy content than current pellet fuels. 1kg of torrefied wood pellets contains the same amount of energy as 2kgs of standard premium grade wood pellets.

Torrefied Wood Energy Density
Torrefied wood pellets contain a much higher energy density than other biomass fuels and standard wood pellets – Image:

With a much higher energy density, it means pellet fuel customers would require less pellet fuel deliveries. It also means you only need a pellet store of half the size of that you would require for standard wood pellets. Another benefit is the reduced transportation with torrefied wood pellets. As customers require less fuel to meet their heating requirements, the same pellet tanker can serve double the number of customers.

Is it only Wood which can be Torrefied?

No, you can produce torrefied pellets from any biomass including Switchgrass, Miscanthus, Straw and Hemp. Therefore torrefied fuel technologies have a big role to play in making pellet fuel a more viable option for consumers.

How does a Flat Die Pellet Mill make Wood Pellets?

Hi, I’m Chris. I started back in 2007.

If you have started to look into the process of how to make wood pellets, you will have started to look in how the pellet mill works. The image below is of a typical flat die pellet mill. Most flat die pellet mills on the market today are imported from China. Many of them are electrical single phase flat die pellet mills with some being PTO pellet presses. Huge volumes of these flat die pellet mills are being produced for farmers to make their own animal feed. However, there was a growing demand for wood pellets around the world for stoves and boilers. There is now a significant demand for these same small flat die pellet mills to produce wood pellets from home.

Flat Die Pellet Mill
Typical flat die pellet mill from China

How does a Flat Die Pellet Mill work?

Flat Die Pellet Mill Cross Section
Flat Die Pellet Mill Cross Section

The image to the right is a cross section of a typical flat die pellet mill. Material enters from above and is compressed between the rollers and die. The process at first would appear very simple. And when the pellet mill and raw material are prepared properly the description of the process is simple. However, true success at making pellets is in the detail. For instance, you need a raw material at the perfect moisture content.

Die or Roller Rotation?

Flat Die Pellet Mill Roller Driven
Roller Drive Flat Die Pellet Mill

So the first thing to understand is the different designs of flat die pellet mill. Either the die will be driven and the roller shaft is stationary (as in the image above), or the die is fixed the roller shaft rotates around the die. An example of a roller drive flat die pellet mill is shown to the right. In terms of which is a better design, there are advantages to each. The roller drive flat die pellet mills are generally better built and able to cope better with the forces that wood pellet production places on the equipment. However, they are also generally more expensive than the die drive flat die pellet mills. If you do want to make wood pellets I would probably recommend you focus on a roller driven flat die pellet mill design.

Inside the Flat Die Pellet Mill

Flat die pellet mills always work on a vertical process, the material falls from above and pellets emerge from below. This is different to ring die pellet press designs, which can be based on a vertical or horizontal design. There is a lot going on inside the pellet mill, and a lot can go wrong which we will look at below.

Flat Die Pellet Mill
The general principle of a flat die pellet mill is a vertical material flow. Material enters from above and wood pellets emerge from the bottom.

Wood which is Too Wet

Generally, when it comes to making wood pellets with a flat die pellet mill, you want a raw material with a moisture content between 12-15%. If the moisture content is more than this it will probably provide results similar to that shown below:

Flat Die Pellet Mill Too Moist
(A) wood before the roller, (B) the die of the pellet mill, (C) material carpet, (D) compression within the die, (E) the finished wood pellet.

Once the flat die pellet mill is up to temperature a lot of steam will be generated. As it’s not possible to compress water, the wood pellets will not be produced to a suitable density. Hence, soft crumbly wood pellets will be produced (E). However, another result could be a blocked flat pellet mill die.

Wood which is Too Dry?

While it’s not possible to produce quality wood pellets with wet raw material, it’s also not possible with very dry material. You need at least some moisture to melt the natural lignin within the wood to act as a binder to hold the wood pellets together. While using a supplementary pellet binder can aid the process, you still need at least some moisture for the process to work.

Flat Die Pellet Mill Too Dry
If the material is too dry it will not be possible to generate the required heat and pressure to produce wood pellets.

Trying to process very dry woody biomass in a flat die pellet mill the result will just be dust (E). This problem can be addressed if a material conditioner is mounted above the pellet mill. You can then use either drip tanks or peristaltic pumps to add small amounts of water to the raw material before it reaches the pellet press.

Problems with the Flat Die Pellet Mill Design

What flat die pellet mills do suffer from is something called ‘roller slip’ or ‘skip’. On a flat die pellet mill, the inner edge of the die and the outer edge of the die are rotating at different speeds. If you think about it, the outer edge has a large circumference than the inner edge of the die. Therefore under rotation, the outer edge has to cover more distance under one rotation than the inner edge. The problem is the rollers touch both the outer edge and the inner edge of the die at the same time.

flat die pellet mill roller skip
Flat die pellet mill roller skip, the rollers are trying to run more slowly at the blue dots compared to the red dots.

The action of roller skip causes flat die pellet mill generally produce wood pellets to a lower quality when compared to ring die pellet mills. It also results in a more rapid parts wear along with increased energy production. Another issue with flat die pellet mills is that it’s harder to set the proper roller and die gap to make quality wood pellets.

Conclusion on Flat Die Pellet Mills

If you want to produce the best quality wood pellets as part of a commercial pellet plant, personally I would only consider a ring die pellet mill. However, if you are a beginner and looking just to get to grips with how wood pellets are made then small flat die pellet mills can serve that purpose.

What is the Ideal Pellet Mill Roller and Die Gap for making Wood Pellets?

Hi, I’m Chris. I started back in 2007.

The questions of what is the ideal pellet mill roller and die gap may seem strange to some people. There are several websites and forums that state that with a pellet press you need to ‘clamp’ the rollers down against the die to ‘build up sufficient pressure to push the material through the die’. However, when you start to really learn about how to make wood pellets you will know that’s a false statement. I need to make it clear straight away. Clamping the rollers down against the die is terrible advice. It may seem necessary on some cheap Chinese pellet makers to force the material through the die. However, you should never ‘clamp’ the rollers to the die on any pellet mill.

By clamping the rollers against the die you will eventually damage the roller bearings. You will also dramatically accelerate die and roller wear and reduce pellet quality. If you go and visit a professional large scale wood pellet manufacturing plant they will tell you that the die and rollers should never touch, there should be no metal to metal contact.

Pellet Mill Roller Gap
There should always be a gap between the pellet mill rollers and die.

So what is the Ideal Gap between the Pellet Mill Die and Rollers?

While the pellet mill die and rollers should never touch, that is not to say that the size of the gap is irrelevant. You want to maintain a gap of 1mm to achieve the best balance of power consumption and pellet quality. This will form a ‘carpet’ of material against the surface of the die. The carpet lay is the first stage of compression and conditioning before the material gets compressed through the die. If you set a gap above 1mm you will have issues with power consumption and potentially stall the motor. The greater the distance between the die and rollers the more resistance. Therefore a gap above 1mm is only recommended for certain animal feeds and other low-density materials. Also, you will only get a carpet to form if the moisture content of the material is correct.

Pellet Mill Roller Die Gap
For the best balance between pellet quality and productivity per hour a 1 mm roller and die gap should be maintained in the pellet mill.

The condition of many small pellet mill dies is also very poor. The dies are often not properly prepared and polished. Therefore to avoid a pellet mill die blockage users clamp the rollers against the die to force the material through.

Creating a Roller and Die Gap on Cheap Pellet Mills

The problem is, particularly on cheap pellet mill imports there is usually no method to set the distance of the die from the rollers. Therefore this usually means that you have to have metal to metal contact. Hence one of the reasons why it is very difficult to produce quality pellets on many small single phase pellet presses.

Top Tip: It is possible to set the roller gap on cheap Chinese pellet mills using the ‘double nut’ method. You place a piece of paper or cloth between the rollers and die. Then using two nuts tightened against each other on the bolt that fixes the rollers you can set the required 1mm roller and die gap.

Conclusions on the Pellet Mill Roller and Die Gap

While you can produce wood pellets by fixing the pellet mill rollers down against the die, sooner or later you will regret it. As the temperature builds the grease within the rollers will start of escape, especially if its not proper high temp grease. Then the rollers will cease up, then you will need a new set of bearings. Furthermore, for running the pellet mill with no roller and die gap you will get a much shorts parts life. The rollers and die will wear out very quickly from the metal to metal contact. There you operating cost per tonne of wood pellets will be much more than it should be.

However, to run a pellet mill with the 1mm roller and die gap you do need the material and pellet mill to be properly conditioned. If you properly prepare the pellet mill and the raw material you will get better quality wood pellets and lower production costs due to the pellet mill parts lasting much longer.

PTO Pellet Mills, what are the Problems when making Wood Pellets?

Hi, I’m Chris. I started back in 2007.

If you’re looking to make wood pellets on a small scale, you’ll be trying to keep your equipment spend to a minimum. Therefore, for those people who already own a tractor, PTO pellet mills are obviously appealing. However, before you considering purchasing any equipment I would encourage you to read my how to make wood pellets page. You should really only start to consider purchasing a pellet mill once you’re confident you understand how the process really works. Hint, its a lot more complicated than most people realise.

PTO Pellet Mill
A typical Chinese PTO pellet mill

The image you can see above is a typical example of a PTO pellet press imported from China. For a pellet mill of that size you will be able to produce around 50 kg/s of wood pellets and up to 100 kg/h of animal feed. A PTO pellet mill of that size will require a 30-40 HP tractor. If you already own a tractor the appeal is obvious. It would mean no need to purchase a separate diesel or electric motor to power the pellet mill, reducing the cost of investment. However, there are various problems with a PTO pellet mill which you need to consider.

No Control over Material Feed Rate

Many people are not aware of how important the rate of feed into the pellet mill really is. Wood pellet quality and press productivity are significantly influenced by the material feed rate. If you just load up the hopper on the PTO pellet mill you are probably going to experience a pellet press blockage. To avoid a blockage and produce the best quality wood pellets you need a consistent rate of feed to create a wave infront to the rollers but not covering the rollers. This way steam created from the pellet making process can escape and not create issues.

PTO Pellet Mill Feed Rate
To produce the best quality wood pellets you want to feed just enough material infront of the roller (A) but no more.

With a PTO pellet mill setup, there is only one source of power at one speed. Therefore a variable speed material feed system is not possible. So the user has to stand by the PTO pellet mill slowly metering in material to produce the best results. This is obviously very time-consuming. Therefore you have to consider the value of the pellets compared to your time to produce them.

The second aspect is torque, while diesel engines do have a lot of torque compared to a gas/petrol unit they still cannot compare to an electric motor, particularly at variable speeds. There is also the question of running costs as a PTO setup is the most inefficient way to produce pellets.

The Problems of Power and Efficiency

The fact is that the PTO pellet mill is not a very efficient wood pellet making the process. In most cases, the tractor engine will be far more powerful than really required. Furthermore, there are the energy efficiency losses from transmitting power from the engine to the PTO and through the pellet mill gearbox.

Tractor PTO
Powering a pellet mill via a PTO is the least energy efficient means of generating power due to mechanical energy losses.

So you really have to consider, for the amount of diesel it takes to run a PTO pellet mill is the process efficient enough? Remember, you have to factor in the other energy costs of processing the material. For instance, when you are making wood pellets from logs, that involves going through a chipper and hammer mill.

The Safety Issue

Finally, there are serious safety concerns around operating a PTO pellet mill. Many people die each year from PTO related accidents. With a pellet mill, you are standing directly next to the shaft. Furthermore, many people choose not the fix the recommend protective covers. Even with the covers fitted, there is still a chance of accidents occurring.

PTO Safety Guide
If you are going to purchase a PTO pellet mill, you should always fit a protective guard.

Conclusions on PTO Pellet Mills

There are several advantages to a PTO pellet mill. It means you don’t have to purchase an additional motor and with the pellet mill linked to the three-point hitch its also portable. However, it’s important to remember the pellet mill is only one part of the pellet production process. You may also need a chipper, hammer mill and potential even some form of drying equipment to get the material to the perfect moisture content. Therefore, you shouldn’t consider a PTO pellet mill purely on its own merits. You need to consider how well a PTO pellet mill would fit into your wider pellet production set up.

Ring Die Pellet Presses, what are the Benefits compared to Flat Dies?

Hi, I’m Chris. I started back in 2007.

After you start to learn the process of how to make wood pellets, you start to think about purchasing equipment. When it comes to purchasing a pellet press you have two main options. Either a flat die or ring die pellet mill. There are a few variations over these designs. For instance, while with a flat die pellet mill the die is always mounted horizontally in the machine, this is not always the case with ring die presses. With ring die machines the die can be orientated in either a vertical or horizontal design. Flat die pellet presses dominate the small scale market. While ring die pellet presses dominate commercial pellet plant operations. But why is this the case, what are the benefits of ring die pellet presses?

Ring Die Pellet Mill
The basic principle of the ring die pellet press design is material is fed into the centre of the die and the rollers compress the material so pellets emerge from the outer surface.

Ring Die Pellet Presses Don’t Suffer from Roller Slip

One of the reasons that ring dies are a superior design is that they do not suffer from roller skip. Due to the speed differences between the point of contact between the rollers and die, roller skip is a significant issue for flat die pellet machines. Ring die pellet mills do not suffer from this issue. The reason being there is no difference in speed between the die and rollers in any position.

Flat Die Pellet Mill Roller Slip
Flat die pellet mill roller skip. There is a slower rotation speed at the blue dots than the red dots. Hence the rollers have to ‘skip’ during operation leading the various issues.

The benefits of eliminating roller skip are reduced power consumption, extended consumable parts life and improved pellet quality. There is only one feature that flat die pellet mill manufacturers claim is superior to a ring die. That is the material flow of low-density materials such as straw and other grasses. While this can potentially be an issue for some ring die pellet mills, it’s generally not a significant issue.

Ring Die Pellet Press
Ring die and rollers.

Are there any downsides to Ring Die Pellet Mills?

From personal experience, I will say that ring die pellet mills are a bit more awkward to deal with when it comes to blocked pellet mill die. With any pellet mill, if the die is not properly prepared then the chances of blockage are increased. With some blockages, it’s possible to run an oily material mix through the machine to address the issue. First, you fix the rollers against the surface of the die (no roller gap) to and then try an process the oily material. If you are not getting anything coming out the other end then it will require you to take the die out of the machine for manual cleaning.

Blocked Pellet Mill Die
It is often easier to deal with blocked flat die pellet mill compared to a ring die pellet mill.

With small flat die pellet mills its often easier to get them out more quickly. Partly because there are fewer parts to take apart, and because the die will be small and light. When it comes to large ring die pellet mill the die will weigh several hundred kilos, even up to half a ton! Once the die is removed, to get the material out will require a punch and hammer or a drill. This process can take a very long time and if you’re not careful you can easily damage the die.

Ring Die Machines provide a more consistent Quality of Wood Pellets

As described above ring die pellet mills do not suffer from roller slip. Therefore when the wood is processed through a ring die pellet mill the material is equally exposed to the same amount of heat and pressure. This means under the right conditions a ring die pellet mill is able to process wood pellets of more consistent quality. The ‘right conditions’ means having the raw material at the best moisture content and the best particle size.

Wood Pellets
Ring die pellet mills generally produce a better quality of wood pellet.

When it comes to pellet binders some people are dismissive, implying that the use of pellet binders means the machine is not designed to process that particular material. Now while this may be the case in some circumstances and it is important to use a die designed for specific raw material, pellet binders should not automatically be dismissed. For instance, even Traeger who make some of the best quality BBQ wood pellets add in small amounts of soybean oil into their process. Granted the oil is not actually to specifically ‘bind’ the wood pellets but to lubricate the process, they still feel the need for an additive. But as you should not in their video, they use large scale ring die pellet mills in their BBQ wood pellet plants.

Conclusions on the Benefits of Ring Die Pellet Mills

When it comes to pellet production there are really very few reasons not to choose a ring die pellet mill. However, you still have to choose a manufacturer who produces their equipment to a high quality and can provide good spare parts support, that’s essential. If you want to learn more about the wood pellet production process please start with my page on how to make wood pellets.

Single Phase Pellet Mills, what are the Problems when making Wood Pellets?

Hi, I’m Chris. I started back in 2007.

When it comes to making wood pellets, your choice of pellet mill is limited by your available source of power. For domestic properties and some commercial buildings, a single phase connection is used which has a voltage between 110v – 240v. For many commercial buildings, a three-phase connection is available which can carry a higher voltage of between 230v – 400v. When it comes to using a single phase pellet mill various limitations have to be acknowledged. These include the maximum power the pellet mill can consume.

The Power restrictions of Single Phase

Single Phase Pellet Mill
A single phase mini pellet mill

If you only have access to a single phase electrical supply you are limited by the maximum power draw the pellet mill can demand. On a standard domestic two/three pin plug the maximum motor draw without tripping will be around 2.2kW. If there is a dedicated connection (similar to that used for a cooker), potentially the motor size could be increased to around 7kW.

However, if you are intending to make wood pellets this is not a lot of power to play with. Quality wood pellet production requires high compression, which in turn demands a high power input from the pellet mill. Without sufficient power, a single phase pellet mill can run into problems.

Potentially Increased Pellet Mill Die Blockages

Blocked pellet mill die
A blocked die on a single phase pellet mill can easily happen.

The number of Amps (power) a pellet mill draws depends on the type of material being processed. For instance, a single phase pellet mill can quite happily process an oily animal feed mix into low-density pellets. However, when it comes to processing wood pellets there are more intensive power demands. As wood has a higher material density and the pellets are also produced to a higher density this can lead to complications. As the single-phase pellet mill starts to process wood pellets the amps will increase. If there is a change with the raw material feed rate or the moisture content changes this could lead to issues.

As the pellet mill starts to work harder to push the wood through the die the motor amps rise. With a single phase pellet mill, it’s very easy to reach the limit of around 6 amps. After this point, the electrical connection will trip out. If this happens with the material left in the die it will start to cool down and harden. Depending on the condition of the die this could lead to a pellet mill die blockage.

Productivity per Hour Restrictions

As a roughly general rule when it comes to making wood pellets it requires 1kW of pellet mill power to produce 10kg/h of productivity. Therefore, on a single phase connection and motor power of 2.2kW, the productivity per hour will be 22kg/h. This is where you really have to weigh up the value of your time to the volume of wood pellets produced.

Wood Pellets
It takes 1kW of power to produce 10kg/h of wood pellets

A pellet mill is not a ‘set and forget’ operation. You need to be actively engaged, monitoring the raw material and pellet press at the same time. Therefore, what you really need to consider is if 22kgs of wood pellets are worth an hour of your time. There is also the matter of pellet mill maintenance to factor in. Furthermore, it’s not really an hour of your time, it’s even more. You also have to factor in the time taken to prepare the raw material ready for the pellet mill. That means reducing it to a suitable particle size and moisture content.

You can only run One Piece of Equipment at a Time

Single Phase Hammer Mill
Single phase hammer mill

As previously stated, a single phase connection means all available power is used by the pellet mill. Therefore, there is no surplus power available to run a hammer mill for particle size reduction. If there was suitably available power you could be using the hammer mill while the pellet mill does its job. As with single phase, there isn’t sufficient power, you have to use one piece of equipment at a time. This therefore obviously increases the total time it takes to produce a fairly small quantity of wood pellets.

There are small hammer mills on the market that use small diesel engines. This would obviously mean you could be using both the pellet mill and hammer mill at the same time. It should be noted that small Chinese diesel engines are not very efficient. Therefore the cost to process the material could be much higher than you would expect.

Is there a use for a Single Phase Pellet Mill?

From reading the above it should be clear that a single phase pellet mill is not a viable pellet production setup for volume. The cost per ton when you factor in the labour/time is not viable. However, there is still a viable use for single phase pellet mills.

Research and testing before investment in a pellet plant is probably the number one use for single phase pellet mills. Before a significant investment is made in a pellet plant a pilot project can be set up to produce small volumes of pellets. This can be a ‘proof of concept’ to help to secure funding. It can also be a useful setup to train future pellet plant operators.

The other exception of use for a single phase pellet mill is for producing BBQ wood pellets. As the profit margins are so high for BBQ wood pellets it can be viable to produce them on a single phase pellet mill.

Final thoughts on Single Phase Pellet Mills

Many people start off looking into purchasing a pellet mill to make wood pellets from home. However, before such a decision is made it’s very important to learn as much about the process as possible. Making good quality wood pellets is a challenge, and even more so using a low powered single phase pellet mill. To make the process easier to deal with its recommend to consider a low inclusion pellet binder. This will aid the process and partly address the issue of power limitations with a single phase pellet mill.

Before you purchase a single phase pellet mill it is a good idea to have a chat with a local electrician who will advise on the best way proceed. A dedicated connection for the pellet mill will probably be their recommendation.

I hope you found the above useful. Remember, before you make any purchase make sure you have researched the process of making pellets thoroughly. With this website, I’m trying to produce as many helpful hints and tips from my experience over the years.

Is a Used Pellet Mill worth the Risk?

Hi, I’m Chris. I started back in 2007.

When it comes to making wood pellets, looking for a used pellet mill may be an option to reduce your initial investment. However, there are potential risks you need to consider before such a purchase. Also before you consider purchasing any equipment I would encourage you to read my posts on how to make wood pellets. You will learn about the best raw materials to make wood pellets from and the perfect moisture content.

Why is the Used Pellet Mill available for Sale?

Used Pellet Mill
Used pellet mill from China

The fact is many of the used pellet presses for sale on eBay are where the individual has purchased a Chinese pellet mill and experienced issues. Now those issues could be down to user error due to a lack of information/experience on the process of producing pellets or the issue could be with the press itself. Either way, it will lead to the item going up on eBay with comments such as ‘barely used’.

If the issue was operator error you could potentially pick up a very cheap pellet maker that with the right help could produce wood pellets. However, it could have also been operator error that actually led to an issue with the press. The rollers may have been clamped down again the die, large pieces of raw material used in the machine etc. They may have found frequent pellet mill die blockages to be too frustrating. The risk is that in some cases there may be damaged bearings, rollers or die. In other cases the pellet mill casting could be broken, there is an element of risk to any used pellet mill purchase.

Are you actually Saving any Money with a Used Pellet Mill?

Flat Die Pellet Mill
Most used pellet mills available are flat die machines made in China.

Let’s presume you are considering purchasing a used/second-hand flat die pellet mill. Odds are that the machine was produced in China. However, there are a lot of resellers on the Internet making the process of making wood pellets appear much easier than it really is in order to sell their pellet mills. So an individual purchases the pellet mill only to realise the process is a lot more complicated than they thought. They try to get a refund which is refused so they try and shift the pellet mill on eBay.

They know they won’t be able to sell the pellet mill for what they purchased it for so try and get between 50% and 75% of the original purchase price. However, the fact is many of these resellers are marking up the price of the Chinese pellet mills by 200-300%. Therefore a second hand (potentially damaged) pellet mill on eBay may still be significantly overpriced.

Purchasing Directly from China

The reality is to is often a better deal to purchase a new pellet mill directly from China than to purchase a used pellet mill from eBay. You can use an import agent however they are going to charge you quite a significant service charger for purchasing a single press. So there are two options.

Asking to Purchase a ‘Sample’ Machine

Common Chinese Pellet Mill
A typical example of Chinese pellet mill

So the best place to get in contact with Chinese pellet mill manufacturers is Alibaba which is an online Business to Business market place. Simply search for pellet mill and various companies will appear. You can contact the companies and explain to them you are potentially interested in starting a business selling their products. You request to purchase a single unit as a test sample. Some will refuse but some will agree to the deal. You can then use the Escrow service offered by Alibaba. They then hold the money on the purchaser’s behalf and only release the payment to the seller if you are happy with the purchase.

Purchasing a Pellet Mill through AliExpress

So AliExpress is basically the retail side of Alibaba, instead of being business to business its sales to consumers. You may not be able to secure quite such a good deal as purchasing a ‘test sample’. However, you will be able to get a much better deal than purchasing a pellet mill from a reseller adding a 200-300% markup. You can also pick up spare parts of the pellet mills at a fairly reasonable price as well.