DIY briquette press

Fuel briquettes, for the production of which sawdust and waste from processing various agricultural raw materials are used, are an excellent alternative to the usual types of solid fuel - firewood and coal. In order not to purchase this fuel in finished form and, accordingly, to make it even more economical, you can make your own briquette press and produce the required amount of euro-firewood from sawdust with your own hands.

Eurofirewood - fuel briquettes in the form of a multi-faceted beam with a hole for smoke removal

Today, two technological schemes are used for the production of briquettes for heating, which, if you have the appropriate technical devices, can be implemented at home. Naturally, to produce Euro-firewood in the required quantity, the presence of basic raw materials is necessary, which can be sawdust, shavings and larger wood waste. It is advisable to make a press for fuel briquettes with your own hands if the raw materials that will be used for briquetting are affordable and can always be obtained in the required quantity.

Features of the production of fuel briquettes

Fuel is made from the following types of raw materials:

sawdust, wood chips, shavings, bark;
cake, sunflower husks, husks of other seeds, incl. croup;
peat;
coal dust.

Briquettes made from wood waste are the most common.

Physics of the process

A portion of crushed raw materials is loaded into a mold and compressed with a press with a force of up to 3000 kg/sq.cm.

The output is a block with a higher density than wood: 1.08–1.40 g/cc versus 0.75–0.85. This fuel burns longer and does not produce sparks.

Application of adhesive

A binder is required to adhere fine particles to each other. Industrial production uses lignin contained in the raw materials themselves. It is a complex biopolymer synthesized by plants. Under the influence of high pressure and the resulting heating, the binder comes out of the cells and impregnates the briquette.

An adhesive is required to hold the particles together.

Thus, factory-made fuel does not contain chemical additives and is therefore environmentally friendly.

Most homemade presses are not capable of developing pressure sufficient to destroy plant cells and squeeze out lignin. Therefore, in home production, third-party binders are used:

Clay solution. Add in an amount of 5–10% of the total weight of the mixture.
Corrugated cardboard and other paper (contains lignin). The material is pre-soaked.
Wallpaper glue. The cheapest one will do.

The proportion of glue and paper is selected experimentally - it depends on the humidity of the raw material and the pressure developed by the press.

The higher the lignin concentration in the wood, the lower the force required to squeeze it out. Data on the most common breeds are given in the table:

Tree name	Mass fraction of lignin, %
Birch	19
Aspen	22
Spruce	27
Pine	27
Fir	30

If a homemade press develops a lot of pressure, you should first try to make briquettes from softwood sawdust. It is possible that a third-party binder will not be needed.

Requirements for raw materials used

A properly prepared starting mass has the following parameters:

Humidity – 4–10%. Excessive amounts of water impair combustion.
Fraction or chip thickness – 2 mm. Large chips are pre-crushed in crushers.
Lack of grass, sand, leaves, soil; bark content – no more than 5% by weight of the mixture. Such components disrupt the monolithic structure of the bar and make it crumbly.

At enterprises, the moisture content of raw materials is adjusted to the required value in heated dryers. In home production, it is kept in the sun and draft.

When using a third-party binder, sawdust is soaked in it, and the finished product is dried.

Equipment for creating heating material

Today, there are many companies that supply equipment for the production of fuel briquettes, and often they also offer installation services. In some cases, lessons are provided on how to use the devices.

To make your own fuel you will need the following:

for grinding recyclable materials;
Briquetting press (hydraulic, screw or impact-mechanical;
finished product.

If it is possible to dry the material in the fresh air or receive it dry from other industries, then you can do without a drying complex, but it should be taken into account that the sawdust should have a moisture content of no more than 13%. And when using sawdust, you don’t need a crusher.

General information about briquetting press

The equipment is produced in a variety of designs. The developed force varies from 500 to 3000 kgf/sq.cm.

Approximate cost in rubles:

mini presses – 70,000–100,000;
budget class models – 200,000;
multifunctional machines with a long service life - from 300,000 to 1,000,000.

A homemade unit can be made at home from scrap materials.

Purpose

The press compresses fine-grained raw materials until they turn into a dense briquette. Expensive models simultaneously heat the source material to a temperature of +150...300°C, which promotes the release of lignin from plant cells.

The press compresses the raw materials into a dense briquette.

Machines designed for the continuous production of Euro firewood cut them into individual bars.

Design features: main elements

The main components of the press:

Mixer. Mixes several types of raw materials until a homogeneous mixture is achieved.
Matrix. Gives raw materials the desired shape.
Punch. Applies pressure on the original mass.
Operating mechanism with drive. Converts electrical energy into compression force.
Bed. The base to which all components are attached.

Some models are additionally equipped with a heater and a knife.

Principle of operation

The mixture enters the matrix, where it is subjected to pressure from the punch. The raw material is compacted with simultaneous molding.

Operating principle of a briquette press.

According to the principle of operation, machines are divided into 2 types:

Intermittent. During production, the cycle is repeated many times: loading of raw materials – compression – removal of the finished product from the mold.
Continuous (extruders). Adding raw materials and squeezing out the product occurs constantly, while at the same time the latter is cut into bars.

Basic elements of the press

The most important element of the press is the mold. The press mold device has a simple design. Its cross-section is chosen arbitrarily; it depends more on the preferences of a particular person, since the shape gives an understanding of what the finished product will look like.

The elements of the device also include a piston and a mechanism that creates pressure. The minimum force that must be applied to obtain Euro firewood is 30 MPa. In this case, there is no need to add a binder, since lignin will bind the material quite firmly.

Species diversity

There are several types of presses:

hydraulic;
screw;
shock-mechanical;
granulators.

The differences lie in the method of creating pressure and the characteristics of the briquettes.

Hydraulic

Machines of this type have the following characteristics:

The production method is intermittent.
The working mechanism is hydraulic: force is created by pumping oil into the cavity of the hydraulic cylinder.
Specific pressure – 500–1500 kg/sq.cm.

The hydraulic machine has an intermittent production method.
Raw materials are loaded in portions into a mold (glass). After compression, the finished briquette is removed.

Hydraulic presses have 2 advantages:

low cost;
briquettes are shaped like bricks (RUF), which makes transportation and storage easier.

Flaws:

low productivity;
relatively low pressure - the density of the bars does not exceed 0.75–0.8 kg/cc.

Screw

Press characteristics:

The manufacturing method is continuous.
The working body is a rotating auger (like in a kitchen meat grinder).
Specific pressure – up to 3000 kg/sq.cm.

The press operates on the principle of extrusion: a screw forces the mixture through a gradually narrowing hole - a die. Due to the conical shape of the channel, the compression force from its walls is several times higher than the pressure developed by the screw. A similar effect is observed when driving a wedge into a crack, which leads to the splitting of a tree trunk.

A screw press forces the mixture through a tapering hole.

Installation benefits:

High density of briquettes – 1.08–1.40 kg/cc. This fuel burns for a long time and produces a lot of heat.
High performance. Thanks to the continuous operation of the extruder, it is possible to produce more briquettes per unit of time than with a hydraulic installation.
The log has a Pini&Kay format - with a hexagonal cross-section and a through hole in the middle. The channel ensures the flow of air to the internal layers and, as a result, the most complete combustion and minimum ash content.

The disadvantage of a screw press is its high cost.

Impact-mechanical

Equipment characteristics:

The production method is continuous.
The working body is a rotating crankshaft with a connecting rod attached to it (crank mechanism).
Specific pressure – up to 2500 kg/sq.cm.

There is another type of extruder, when the raw material is forced through a die by a piston moving back and forth.

In terms of cost and productivity, mechanical impact presses occupy a middle position between hydraulic and screw models. The same can be said about the density of the bar: it is 1–1.15 kg/cc. It has a round cross-section (Nestro type) with a through hole.

The mechanical impact press operates continuously.

The disadvantage of the equipment is accelerated wear of the bearing due to impact.

Despite this, such presses have become widespread due to the optimal combination of installation price and product quality.

Press granulator

This is a universal extruder for the production of fine-grained pressed products. If the raw material is crushed grain, the output is compound feed; if sawdust, peat, seed husks, etc. - fuel granules (pellets). The advantage of small-caliber briquettes is the possibility of automatically feeding them into the combustion chamber of the boiler using a screw or piston feeder. The heat generator must be equipped with a special pellet burner.

Types of presses

There are 4 types of press. The difference between them is the principle of operation and the cost of the device.

Kinds:

mechanical impact press;
Hydraulic Press;
screw press;
press granulator.

The operating principle of a mechanical impact press is based on impacts, under the influence of which chips are forced through a die. The advantage of this device is that in addition to wood waste, you can press the remains of MDF or coal dust. The device can operate for a long time without human intervention.

The hydraulic type sawdust briquetting press is similar in principle to the use of a hydraulic jack. The mold is filled with raw materials and pressure is applied to it by a hydraulic cylinder. The disadvantage of this model can be considered the low volume of products. To press sawdust and create euro-firewood in a hydraulic press, it is necessary to use a binder.

The production of pellets using a screw press is carried out under high temperatures. The chopped wood is fed to the auger through a die. Under the applied pressure, the raw material is pressed. Due to the high temperature, the wood loses its natural binder, as a result of which the pressed timber has sufficient strength. The briquetting line has similar features to the operation of a meat grinder, that is, the finished raw material is placed in a hole, mixed in a hopper and exits through a tapering channel.

Pressing sawdust using a granulator press is a fairly quick process. It will only be possible to produce small-sized products. A significant advantage of this product can be considered its cost and the availability of various additional devices that can improve the quality of the product.

To obtain fuel from sawdust, it is necessary to prepare it using any type of press. The moisture level of the raw materials should be in the range of 4-10%, and it must first be crushed into fractions measuring 25x25 mm.

Press selection criteria: what to look for

When choosing a machine, consider the following:

Electric motor power. It is limited by the capacity of the circuit breaker at the entrance to the house and the cross-section of the cables. The most energy-intensive are screw units.
Distance to the supplier's service department. The closer it is located, the faster the repairs will be completed and the less losses there will be from equipment downtime.
Telephone consultation. A useful service from a supplier or dealer can help you avoid mistakes and save money.
Volume of available raw materials and market capacity. The costs of purchasing a machine with excessive productivity will be unreasonably high, and along with them the cost of repairs. These factors will increase the payback period of the equipment and lead to a decrease in production profits.

When choosing a machine, consider the power of the electric motor.

Equipment selection

When choosing a sawdust press, important factors to consider are:

purpose of equipment;
what raw materials does it work with;
type of briquettes produced;
device power;
planned volume of finished products;
complete with other equipment to obtain a high quality product;
functionality of the selected model;
operating mode of the unit and features of its maintenance.

You also need to pay attention to components that are subject to wear. Frequent repairs and their cost will help determine the rationality of purchasing a particular model.

When choosing a press for personal use, you should remember that the equipment should be simple with the ability to customize parameters. If the product is not planned to be put up for sale, then it is enough to purchase just one unit. To make your purchase cheaper, you can take advantage of interesting offers on the sale of used devices.

When choosing a press for personal use, you should remember that the equipment should be simple with the ability to customize parameters

Methods for creating a device

It is impossible to make an extruder at home. All homemade machines press briquettes into a mold (glass) in an intermittent manner.

The main task of the designer is to ensure a specific pressure of at least 150 kg/sq.cm. This value is determined by 2 factors:

force generated by the press (direct relationship);
cross-sectional area of the mold (reverse).

By selecting the ratio of these parameters, the desired characteristics are achieved.

For example, a machine presses on a portion of raw materials with a force of 1350 kgf. If the block has a cross-section of 5x5 cm, the specific pressure will be:

P = 1350 / (5 x 5) = 54 kgf/sq.cm

At such low rates, the briquette will crumble. By reducing the dimensions of its cross-section to 3x3 cm, the designer will increase the specific pressure to:

P1 = 1350 / (3 x 3) = 150 kgf/sq.cm

There are several ways to achieve high force.

The designer's task is to ensure the specific pressure of the press.

Use of muscular strength and leverage

This is the simplest version of the press; all its elements can be made at home.

A strong pipe is used as a lever, for example a reinforced water pipe with a diameter of 40–50 mm and a wall thickness of 4–4.5 (mm). One end of it is equipped with an axis and fixed in a bracket so that the other side can be raised and lowered.

A rod with a punch is attached at a short distance from the point of rotation.

The compression force will be equal to Q = P * (L / L1), where:

P – operator’s weight acting on the free end of the lever;
L – pipe length;
L1 – distance from the point of rotation to the junction of the rod and the punch.

Example:

operator weighs 90 kg;
lever length – 3 m;
the distance from the pipe rotation point to the punch is 0.3 m.

Under these conditions, the compression force will be:

Q = 90 * (3 / 0.3) = 900 kgf

It must be taken into account that the same force acts on the bracket at the point of rotation of the lever, so it must be strong.

To achieve a pressure of 150 kgf/sq.cm, the cross-sectional area of the bar must be equal to:

S = 900 / 150 = 6 sq.cm

The lever installation is designed so that briquetting is carried out in one step. Otherwise, you will have to waste time adding raw materials, which will lead to a decrease in productivity.

The immersion depth of the punch depends on the volume of the portion. It is calculated using the formula A = H * (1 – (p1 / p2)), where:

H – height of the glass;
p1 and p2 are the density of raw materials and briquettes, respectively.

The larger A, the further the rod needs to be moved from the point of rotation. But this leads to a decrease in compression force.

The parameters are selected as follows:

Calculate the cross-sectional area of the pipe from which the glass will be made.
The required force is calculated and based on this the distance of the rod to the point of rotation is determined.
A test briquette is made.
If in 1 approach it was not possible to achieve the required degree of compression, cut off part of the glass to reduce its length.

Formula for calculating the piston pressure force (m) depending on the force applied by a person (M), the distance from the piston to the lever attachment point (l) and its total length (L)

If high productivity is not needed, the briquette is made in several stages, adding more raw materials.

To increase the pressure on the lever, you can attract an assistant.

Application of hydraulic jack

A household hydraulic jack develops a force of 30–40 tf. If you equip a press with it, the available mold area will be:

S = 30000 / 150 = 200 sq.cm

The hydraulic jack develops a lot of force.

This machine can be equipped with several forms. Then the frame for the punches is made of durable rolled products, for example an I-beam or a thick-walled profiled pipe.

The disadvantage of a press based on a hydraulic jack is the long cycle time. But it has higher productivity, and the briquettes are more similar to those made industrially.

The design of a typical hydraulic press consists of a frame and a movable beam on which a jack is placed. The system returns to its original position due to the action of springs

Screw pressing mechanism

Another device for enhancing muscle strength is a screw. The amount of pressure it creates is calculated based on the “golden rule of mechanics”.

L1 / L2 = Q2 / Q1, where:

L1 – path traveled by the point of application of muscular force;
L2 – movement of the punch mounted on a screw or lever;
Q1 – muscular strength;
Q2 – pressure developed by the press.

Example:

the length of the handle in the screw shank is 80 cm (2 arms of 40 cm each);
force applied by the operator – Q1=40 kgf;
screw thread pitch – 3 mm.

The screw pressing mechanism enhances muscle strength.
For 1 revolution, the point of application of muscular force, i.e. the end of the handle will go the following way:

L1 = 2 * P * 40 = 2 * 3.14 * 40 = 251.2 cm

The punch will drop to L2 = 3 mm = 0.3 cm. The force of its influence on the raw material is equal to:

P2 = (L1 * P1) / L2 = (251.2 * 40) / 0.3 = 33493 kgf

The actual force will be less because The operator will spend part of the energy to overcome friction in the screw-nut pair. The average efficiency of such devices is 25–30%. This means that the press considered in this example presses on a portion of raw materials with a force of 33493.3 * 0.25 = 8373.3 kgf.

Advantages of screw presses:

the greatest strength among hand-held devices;
compactness;
simple design.

Flaws:

the cycle is longer;
The manufacture of the screw and nut will have to be ordered by a turner.

The operator must control the applied force, otherwise the thread may be stripped.

It is recommended to increase the pressure little by little and, as soon as an acceptable result is obtained, put a mark on the screw indicating the extreme position.

How to make briquettes?

The technological process used in production cannot be carried out at home. The reason is the lack of pressing or extrusion equipment capable of creating a pressure of at least 30 MPa. Without this, lignin cannot be isolated from wood and homemade briquettes will not be compressed. The solution is simple: you need to add a binder, which is ordinary clay. It is mixed with sawdust in a ratio of 1:10 by weight (1 kg of clay per 10 kg of waste), diluted with water and mixed thoroughly.

The resulting composition is filled into the mold and the mechanism is activated. If the production of fuel briquettes is done manually, then it is necessary to apply maximum force and hold the lever until the water runs out. Then the product is carefully removed and placed on an area in the open sun to dry. You can start filling out the form again and extruding the next “brick”.

Instructions for making a press

To create a homemade machine you will need the following tools:

welding machine;
grinder with cutting discs for metal;
drill;
roulette;
pencil or marker.

To create a homemade machine, you need a welding machine.
The procedure depends on which drive will be used.

Manual

They start with making the frame. This part absorbs all the forces arising in the structural elements, so it must be strong. The bed is a frame made of a thick angle or profiled pipe with reinforcement in places subject to the greatest pressure.

At the next stage, a mold is made. To do this, a fragment of the required length is cut from a round or square pipe with thick walls. Several thin holes are made at the bottom of the glass to allow air and moisture to escape.

You need to think about a way to remove the finished briquette from the mold.

There are 3 options:

The glass is equipped with a movable bottom with a spring underneath. It pushes out the briquette after the load is removed. The disadvantage of this solution is that the spring wears out quickly, losing its elasticity.
They make a removable bottom. It is dismantled at the end of the cycle, then the finished briquette is pushed out by a press.
Use a collapsible glass of 2 halves. Before pressing, 2 rings of reinforcement are put on it.

The mold is placed in a container or scalded around the perimeter so that the water that spills out of it during the pressing process does not spread.

A hand press begins with the manufacture of a bed.

The punch is cut from a steel sheet with a thickness of at least 3 mm.

Finally, a bracket is welded to the frame, after inserting the lever axis into it, or 4 stands with a nut for the screw mechanism.

Drawings of a press for making briquettes

With electric motor

The model based on a hydraulic jack with a pump and motor is subject to higher requirements in terms of strength. Proceed in this order:

Make a welded frame from channels.
Weld 1.5 m long posts in the corners.
Between them, attach a drum for mixing sawdust and binder, removed from an old washing machine or made from a large diameter pipe.
Below, install a galvanized steel tray to feed the mixture into the mold.
Attach a hydraulic jack to the racks.
Make and then install the glass and punch in place, as in the manual version.

The press is ready for use.

Homemade or purchased

The purchase of a press is justified in cases where it is planned to set up production. There is no need to purchase equipment for the production of briquettes, which will subsequently be used only for household needs. In addition, the cost of the units is high, not everyone can afford it. Yes, and installation requires a separate room.

According to the technological process, raw materials need to be prepared before processing, which means a dryer and a grinding device are required. In addition, after production, finished briquettes need to be stored in a dry room, which simply may not be available.

Handicraft production will not produce a high-quality product; the briquettes will have insufficient density, and this reduces the specific heat of combustion. Having weighed all the factors, we can summarize that there is no point in purchasing expensive equipment.

If your house has a boiler for solid fuel, you can build a press with your own hands. This will require available materials, as well as familiarization with design diagrams in order to choose the appropriate option.

Advantages of using ready-made presses for production purposes:

simple equipment design;
the ability to replace worn components;
selection of models of different power and performance;
the technological process does not require special knowledge and skills;
You can set up a workshop in a small room.

When deciding to start production, it is worth considering important factors:

type of raw material, its availability;
approximate volume of processing for a certain period of time;
required areas;
scheme for selling finished products.

For large-scale production, it is recommended to purchase automatic and semi-automatic equipment. The units are characterized by high efficiency and wear resistance of working units.

The production of fillers for animal trays can be put into production using granulators. The diameter of the products produced just meets the standards, and high density is not required.

Useful tips and general recommendations

The creators of homemade briquetting machines advise doing this:

Start designing with a detailed drawing indicating dimensions. This will avoid mistakes and accurately determine the amount of materials needed.
Entrust the strength calculations of parts to a mechanical engineer or builder who is well versed in the strength of materials.
Periodically check the product for bends and distortions and, if found, eliminate them. Otherwise, the quality of the briquettes will suffer.
Dry the finished bars in the sun or in a ventilated area. This will ensure high calorific value of the fuel.

Using clay as a binder, make sure there is no soil in it. Otherwise, the briquettes will crumble.