As we noted earlier, ball drum mills are used in all industries where it is necessary to grind material. In such mills, steel grinding balls are used as the grinding medium in most cases.
In this publication, we will consider the use of steel grinding balls in the grinding process. This process is preparatory when creating a mixture for combustion in boilers for.
To create high-quality fuel for furnaces of TPP blocks, which is made on the basis of coal, it is necessary to achieve the maximum degree of grinding (10-18% of the residue on sieve No. 008) of the material and to reduce humidity to the maximum.
Drying and grinding of fuel can be carried out separately or combined in one unit. When separating these processes, the coal is dried in drying drums, and ground in short ball mills. For grinding coal, conventional ball mills of the ShBM brand are used. The drum length to diameter ratio is typically 1.5:1.
Since the times of the USSR, grinding balls with a diameter of 40 mm of the second and third hardness groups have been used to grind coal at thermal power plants. This is due to the rather low hardness of the material to be ground and the absence of grinding balls of higher hardness groups in the past.
Tracking the world practice of coal grinding, Energosteel specialists were among the first to offer their customers to use grinding balls of the fourth and fifth hardness groups when grinding coal. Numerous tests were carried out, which proved that the use of grinding balls of the fourth and fifth hardness groups leads to a significant reduction in the cost of grinding one ton of coal. At present, almost all energy storage companies in Ukraine use steel grinding balls with a diameter of 40 mm produced by Energosteel Plant LLC of the fourth and fifth hardness groups.
The mills operate in a mixed mode, i.e. part of the kinetic energy of the grinding balls is directed to impact (to destroy pieces of materials), the rest is to abrade the material into dust. To increase the performance of a ball mill, coal is pre-crushed to grains of 8-10 mm. For coarse and medium crushing, both jaw and roller crushers are mainly used. Hammer mills are used for finer grinding. But when working with coal, special care should be taken, as it is flammable and explosive when finely crushed. In this regard, the crushing process has been replaced by grinding in ball mills.
Small grains of fuel formed in the mill in the form of a dust-gas mixture are fed through a pipeline to a continuous separator to separate large grains, which then return through a pipe to the mill for regrinding. The finished product also in the form of a dust-gas mixture enters the cyclone for the deposition of coal dust from the gas stream.
The gases freed from coal dust enter a powerful fan and are forced by it into the branch pipe of the rotary kiln blower fan, through which coal dust is blown into the furnace through a nozzle. The dust deposited in the cyclone is poured into the hopper, from where it evenly enters the nozzle through the feeder, is picked up by the gas flow from the blower fan and is introduced into the furnace.
It should be noted that today, grinding balls produced by Energosteel Plant LLC are used in almost all thermal power plants in Ukraine. Thanks to the specialists of our company, the established stereotype was “destroyed” that when grinding coal, only grinding balls of the second and third groups of hardness are used. A number of industrial tests were carried out, which showed that the use of grinding balls of increased hardness does not affect the quality of grinding and wear of the drum armor. And by reducing the specific wear of grinding bodies, a reduction in the cost of grinding 1 ton of coal is achieved. Also, the time of additional loading operations is reduced, which generally leads to an increase in the efficiency of the ball mills.
Every fan of moonshine easily goes through the first two stages of making moonshine at home. He will be able to make mash and distill it into raw alcohol. But with the purification of alcohol, many have problems. However, there is nothing complicated in such technology. One of the most effective and environmentally friendly methods is cleaning moonshine with charcoal or carbonization.
The structure of coal allows you to absorb molecules of fusel oils and other impurities, as well as absorb the specific unpleasant smell of moonshine. Thus, the final taste of the drink is improved, it becomes less harmful and, when consumed in moderation, is not harmful to human health.
Please note that not all charcoal is suitable for cleaning alcohol. Its correct choice is the key to the quality of this process.
Which coal to choose?
To purify moonshine, charcoal (for example, birch) or coconut charcoal, which is obtained through pyrolysis, is best suited.
The most affordable brands that show the best results are BAU-A activated birch charcoal and BAU-LV coconut. The fact is that they were originally produced for use in the alcoholic beverage industry.
Activated charcoal tablets are not the best choice. The problem is that it is often made from animal bone tissue. Such material does not have the necessary properties that would make it possible to obtain high-quality moonshine.
Do not remove coal from a gas mask or any other device. The only exception to this rule is charcoal, which is used in water filters. However, if you take such material, then you need to make sure that it does not include foreign impurities.
A separate line is charcoal for barbecue or barbecue. It also allows you to remove harmful chemicals and compounds from the made moonshine. Please note that it is burnt material that suits us.
Coal for barbecue should be removed from the grill while it is smoldering. After that, it must be placed in a metal dish and tightly closed with a lid. For the effect we need, it is necessary to create tightness, that is, no air should flow to the smoldering coal. Only after the material burns out to the end can we use it to filter moonshine.
This cleaning process has an interesting feature. After it, the drink acquires an interesting aroma of smoke and fire. For many people, such homemade smoky alcohol is especially to their taste.
Now let's talk directly about how to clean moonshine with charcoal.
The right technology
Selected charcoal or coconut charcoal must be carefully crushed in any way convenient for you. The smaller the particles, the better the purification process will be.
First of all, we should dilute the prepared moonshine with water. The optimal strength is from 40 to 50 degrees. Pour the crushed angle into a clean container of a suitable volume. Pour diluted moonshine into it. It is important to keep the correct proportions. So, 25 grams of coal goes to 0.5 liters of moonshine.
Now it remains for us to hermetically seal the container and leave it in the pantry for infusion for 4-7 days. Remember to shake the container well every day.
Alternative technology
This technique is less commonly used, although, in my opinion, it has its clear advantages. It involves the use of a simple carbon filter during the process of the first distillation (distillation) of moonshine.
Many moonshine practitioners ask how you can make such a cleaning device with your own hands. Everything is incredibly simple.
We will need any funnel available at home. To begin with, we place 1-2 cotton pads in it. Sprinkle a layer of crushed charcoal on top. 2-3 cotton pads are additionally lined even higher.
Now we just have to place the do-it-yourself carbon filter under the stream of moonshine flowing from the moonshine still.
This method, of course, is inferior in efficiency to the one described above. However, such cleaning can also make the drink much better and tastier.
1. If in doubt about the amount of coal that is needed to purify alcohol, then it is better to put it a little more. It will not harm the drink in any way.
2. Once used charcoal must not be reused.
3. If you use different brands of coal for cleaning moonshine that were recommended above, then there is always a danger of spoiling the moonshine. To insure yourself against such an unfortunate accident, first test a small amount of the purchased product on a small amount of moonshine.
4. Using the methods described above, you can purify store-bought vodka. Believe me, the result is worth your time and effort.
Do not forget to share your own experience in purifying homemade alcohol in the comments to this article.
Homeowners who heat their homes with solid fuel stoves are well aware of how difficult and inconvenient it is to burn fine fractions of coal, and even more so coal dust. Part of such fuel is poured into the ash compartment and ends up in the waste, the other blocks the air flow from the grate and therefore does not burn well.
The solution to the problem is to compress this small thing into, giving good combustion and generating a lot of heat. Industrial coal briquetting has been used for a long time, but the pressing technology can also be implemented at home. How to do this - we study in this material.
Production of coal briquettes in the factory
Fine coal fractions and dust are characterized by low density and low specific calorific value. But they can be bought cheaply, and then turned into high-quality fuel by compacting in a limited volume. Simply put, to make pressed coal briquettes, whose density and calorific value are much higher.
This is how factory-made (left) and home-made (right) coal briquettes burn
To make such briquettes from fine coal with your own hands, you need to figure out how and with what machines they are stamped at the factory. Equipment for the production of heating briquettes is a technological line consisting of the following units:
- crusher;
- drying chamber;
- briquetting press.
Note. Items of equipment are listed in the same order in which they stand according to the technology. The supply of raw materials and its movement between installations is carried out by means of belt or screw conveyors.
The process of pressing coal fuel is as follows:
- In the crusher, coal small things are crushed to particles of the same size, depending on the characteristics of the pressing equipment. The maximum allowable fraction size is 6 mm.
- In the dryer, the moisture content of the raw material is reduced to a value of 15% (maximum).
- The last stage is pressing, performed under pressure from 20 to 120 MPa, depending on the technology used.
Stamp (roller) presses with a capacity of 10 and 25 tons per hour Sometimes, for the strength of the final product, organic or mineral binders are added to the raw materials, and before compacting the mixture, it is heated to a temperature of 250-350 ° C. There are 2 ways of pressing coal briquettes for heating:
- on stamp (roll) presses;
- through extrusion machines.
The stamp press compresses the heated coal mixture in special forms, developing a force of 100-120 MPa, after which the briquetted coal undergoes a cooling and packaging process. The output is products in the form of "pills", "pads", cylinders and bricks with holes.
This method of production of coal briquettes is used for the manufacture of fuel in large quantities and entails considerable financial and energy costs.
Production by extrusion consists in forcing raw materials with a screw press through a matrix with calibrated holes. At the output, we have a cylindrical coal briquette in the form of a "sausage". This is a cheaper, but less productive coal briquetting technology.
Coal Dust Extruders The characteristics of the fuel are affected by the composition of the initial raw materials - brown or hard coal, the presence of binders and other factors. But usually the calorific value of a factory briquette is at least 7 kW / kg at a moisture content of 8% and a maximum ash content of 8.5%.
How can you make charcoal briquettes with your own hands?
At home, it is impossible to implement industrial technology. The reasons are the high price of equipment for the production of coal briquettes, high energy costs and the need to coordinate their actions with local authorities. But the owner of a private house does not need to launch a production on a grandiose scale in order to provide heating for the home. It is enough to make 3-4 tons of coal briquettes, which will be enough for the whole winter.
Compressed coal in briquettes can be obtained in two ways:
- weld a machine for forming a briquette from rolled metal and extrude products manually;
- assemble a screw press with your own hands to briquet coal fines by extrusion.
In both cases, it will not be possible to achieve characteristics close to those of factory-made fuel. But you can successfully heat the house by burning home-made briquettes instead of coal dust, which is much more convenient and practical.
Pressing by hand
For manual extrusion, a machine well known to many craftsmen for making bricks at home is suitable. Its frame is welded from shaped pipes and corners 40x40 mm, a receiving hopper is installed on top. A manual mechanism for pressing products in a rectangular shape is attached to the frame. A drawing of a homemade press for manual briquetting of coal is shown in the figure:
The rectangular shape used for making bricks can be replaced with a cylindrical one, and plugged tubes can be placed inside so that there are through holes in the products. They are needed for better burning of a hand-made coal briquette.
The technology of manual briquetting of coal looks like this:
- Raw materials must be crushed. The smaller the fraction, the stronger and better the homemade briquette will come out.
- Pour in some water and stir until the mixture is molded with your hands. Some home craftsmen add clay as a binder, but this will increase the ash content of the fuel.
- Pour the mixture into the hopper, and from there fill the form. Squeeze out the briquette by pressing the lever.
- The lever pushes the product out during the reverse stroke. After it should be removed and placed in a sunny area to dry. Pressing details are shown in the video:
Briquetting on an extruder
This more productive method will require financial costs for the assembly of a screw press, consisting of the following elements:
- a body made of a thick-walled steel pipe, machined from the inside to fit the size of the screw, or made from a solid metal blank on a lathe;
- auger made of carbon steel of increased hardness;
- a matrix with one or more holes is made from the same steel;
- electric motor with a power of at least 4 kW;
- belt drive on multi-ribbed pulleys (at least 3 belts);
- receiving bunker.
Note. Instead of a belt drive, you can use a gear drive, but then the drive will be rigidly connected to the shaft. In the event of any accident, the gearbox or auger may fail.
The principle of operation of the briquetting extruder and homemade screw (right) The most difficult thing is to make a body, a matrix and a screw. For this, it is better to turn to a familiar turner, at the same time he will turn multi-ribbed pulleys of the required sizes for you. Please note: the diameters of the pulleys should be selected so that the rotation speed of the auger does not exceed 200 rpm. The powerful engine of the machine must be grounded and connected to the house electrical network through circuit breakers.
small homemade extruder The technology of briquetting on an extruder is quite simple and is implemented in several stages:
- Raw materials, if possible, grind and mix with water to a thick consistency.
- Turn on the extruder motor and load a portion of the coal mixture into the bunker with a shovel.
- Break off the “sausages” emerging from the holes of the matrix along the desired length and lay them out on a drying rack.
The process of making fuel briquettes from coal is shown in detail in the following video:
About the benefits of coal briquettes - conclusions
If we think theoretically and take into account the assurances of the manufacturers of coal briquettes, then in terms of calorific value they should win over all other types of solid fuel. After all, only pure anthracite is able to release 7.7-8 kW from 1 kg when burned. Firewood and wood briquettes are far behind in terms of specific heat of combustion, since they emit no more than 5 kW / kg.
But judging by the feedback from users of solid fuel boilers on thematic forums, the demand for briquetted coal is inferior to any type of wood for the following reasons:
- flare up poorly and give off little heat;
- form a large amount of ash, and even pebbles, repeating the shape of briquettes;
- crumble into dust during transportation;
- give off a very unpleasant odor before and during combustion.
High-quality briquettes (on the right) with their black sheen noticeably differ from brown coal fuel, which does not burn very well in heating boilers and furnaces If we analyze all the reviews about coal briquettes, it turns out that 70% of them are negative. This is primarily due to the fact that fuel producers are trying to make a profit using waste raw materials - sludge, charge and other obscene varieties of hard and brown coal. A briquette pressed from the remains of anthracite is rare.
This suggests the conclusion: if you want to get good fuel, then use the appropriate raw materials for briquetting with your own hands. When at your disposal there is only dust and fines of low-calorie grades of coal, then it is not always advisable to press them. On the other hand, such briquettes can be burned together with firewood, reducing the cost of their purchase.
