Wood chips for wood concrete is the main component in the composition of the material (from 75% to 90% of the total volume). The selection and preparation of wood filler is an important step that directly affects the structural and thermal insulation characteristics of wood concrete.
Almost any wood is suitable for wood concrete. The best option would be to use softwood (eg pine, spruce) or hardwood (eg birch, oak, poplar, aspen). It is categorically impossible to use larch, beech (due to the high content of substances harmful to cement - sugars), you also cannot use freshly cut wood, it must lie down for 3-4 months.
For the production of wood chips, any logging waste (branches, branches, tops of trees), woodworking waste (slab, cylinder remains), secondary waste (wooden furniture, pallets, etc.) are used. The volume of wood filler should contain no more than 10% of bark admixture, no more than 5% of needles and leaves by weight of dry filler.
Why are pine needles better? Wood contains substances that adversely affect the characteristics of wood concrete, especially strength: various groups of sugars, starch, extractives. Their content in conifers is less than in hardwood and other species. In any case, the aggregate made from the above species needs further preparation and processing. Simply removing sugars from hardwood aggregate, as opposed to conifers, takes a little more effort and components.
The chemical composition of wood species
Wood chips for wood concrete: shape and size
The geometry and size of wood chips for the preparation of wood concrete mixture is determined by GOST 19222 for wood concrete.
Wood chips for wood concrete
First, according to GOST 19222, the wood fraction must have a needle-like shape to create a reinforcing effect and increase the strength of the material. Secondly, the best wood chips for wood concrete must meet the following requirements:
- length should not exceed 30 mm (optimal length 20 mm)
- the width should be no more than 10 mm (the best option is 5 mm)
- thickness 5 mm
Wood concrete chip making machine
The correct geometry and size of aggregate fractions can be obtained by making it on chippers and chippers. A great way to get the correct needle shape and chip size is to use wood shredders. However, a wood shredder is a very expensive machine. Chippers for wood concrete (hammer crushers) will give not the worst result. It is also possible to produce coarse fractions on rotary chippers and then re-grind in a chip crusher.
Wood shredder
If you buy one of the above machines, you can easily make wood concrete chips with your own hands. However, in most cases, wood aggregate is easier to obtain from forestry companies.
Preparation of wood chips for wood concrete
Harmful substances contained in wood filler negatively affect the strength of wood concrete. Therefore, an important stage before the manufacture of wood concrete mixture is the preparation and processing of wood filler.
There are the following ways to prepare a placeholder:
Physical way
This implies the treatment of wood with water, which washes out a significant part of the water-soluble substances. That is why freshly cut wood contains more water-soluble sugars than driftwood. Wood stored under a canopy will contain more water-soluble substances than wood that has been exposed to rain. A great effect can be achieved by prolonged soaking of chips in the pool, but this requires space. It is enough to soak for a day in plain water or 2-3 hours in heated water.
Chemical method
The easiest way: oxidation of tannins with atmospheric oxygen. For this, the wood is kept in the air, and preferably under the sun.
Chemical reactions that occur during the processing of wood chips with chemicals convert sugars into insoluble and harmless compounds, and also create an impermeable film. To envelop wood waste with an impermeable film, urea-formaldehyde resin (KS-11 or KF-MT-P) is used. To reduce the influence of sugars harmful to cement, before creating a cement mixture, wood concrete chips are impregnated with a mineralizer (4 - 10% bleach solution). The impregnation process is called mineralization.
In practice, it is popular to treat wood filler with solutions of calcium chloride, water glass and sulphate alumina to eliminate the effect of harmful sugars on cement. Calcium chloride should only be used on seasoned softwood chips. When using liquid glass and sulphate alumina, the wood species and the time of its exposure are not important, however, when using them, the strength indicator of the wood concrete is almost halved.
Calcium chloride or calcium chloride CaCl2
Biological way
The elimination of woody poisons is carried out using catalysts, which can be bacteria. This method includes elementary heating of wood. It activates biological processes that lead to partial fermentation and oxidation of water-soluble sugars. During the drying process, the sugars become insoluble: they vitrify and crystallize.
Combined method
This method combines the above-described chemical and physical methods. However, it must be admitted that the combined method is laborious.
A known example of a combined method used in England. Boil the wood filler for 10 minutes, then rinse in water. This partially removes water-soluble sugars. Then it is boiled in a 20% solution of ferrous sulfate to precipitate tannins.
Another recipe for the combined method: chips are soaked in liquid glass from 5 hours to 24 hours, then they are washed and dried.
The section GOST 19222 "Determination of the suitability of wood filler" describes a method by which you can check the effectiveness of a particular method.
Natural unpainted wood chips are suitable for mulching the soil and solving such tasks of landscape design as dumping paths and areas.
It is a comfortable, completely natural material without any chemical additives. You will definitely find a use for it at your dacha!
Note that these are hardwood chips (birch, linden, poplar, maple and aspen). You don't have to worry about mulch or scattering of these chips acidifying the soil or damaging your plants.
Wood chips are very convenient to use. All work can be carried out independently, because they do not require any special physical strength or any special knowledge. Ease of use is also enhanced by packaging. We sell wood chips in sealed 40 liter bags. The package is voluminous, but not heavy. It will be convenient for you to work with it. Delivery and storage of chips in packages is also not difficult.
Deciduous wood chips will make your site look beautiful and your plants healthy.
For comprehensive weed control, we suggest using DuPont ™ Plantex® garden geotextiles. The material creates favorable conditions for healthy plant growth, its unique design allows air, water and nutrients to pass through, allows the soil and plant roots to breathe, while keeping weeds underground.
You can read the technology of using geotextiles in the description of any product from DuPont ™ Plantex®.
Soil mulching
Mulch is a natural product that is used to cover the top layer of soil, lawns, and personal plots.
Beneficial features
When people use and exploit land in urban conditions, bare, unprotected areas are formed on it, which has a very bad effect on the appearance, composition and microflora of the soil. Natural decorative mulch will help to cope with this task. It brings not only benefits, but also the aesthetic beauty of landscape design.
Materials for mulching can be very different, depending on the desired effect: stones, pebbles, decorative sand, needles, straw, chips (natural and decorative), wood shavings, bark, cedar shells and husks, and much more.
The advantage of bark, chips and shells over stone, granite, crushed stone and other similar materials is that bark and chips reduce the risk of soil compaction, improve the physicochemical characteristics of the upper soil layer, and activate the development of microorganisms beneficial to plants. Due to its porous structure, natural mulch maintains soil moisture during dry periods. Also, these natural materials for mulching maintain the temperature regime: they protect the soil from hypothermia in winter, overheating and active solar exposure in summer, equalize daily temperature fluctuations in autumn and spring, and inhibit the growth of weeds. The earth under natural materials breathes, allows air and water to pass through. Natural mulch enriches the soil with oxygen, giving free air access to the soil and regulates its acidity.
Coniferous mulch has many beneficial properties:
- exceptional beautiful appearance
- antibacterial effect: wood-boring beetles do not live in them. Due to this property, there is no need for chemical treatment in the production of wood and bark, while other species are subject to decay.
- contain antioxidants - substances that help the body in the fight against aging and the occurrence of various diseases, especially under conditions of stress, polluted environment, radiation.
- throughout the entire service life, Siberian and Angara pine larch evaporate natural flavonoids, which, entering the human respiratory tract, prevent viral and colds
- Siberian larch and Angara pine grow in ecologically clean areas, due to which they do not contain allergens
- the bark and chips of these tree species are resistant to decay and mold
Mulch has not only useful but also decorative qualities.
Thanks to the bright colors, you can diversify your garden, lawn, playground or playground, park, flower bed, lawn, etc.
In the production of colored decorative chips, only natural, stable, harmless dyes are used. Modern colors are environmentally friendly materials with a rich range of bright colors and natural warm tones that will create a healthy, natural, cozy atmosphere.
Another advantage of the shell, bark and chips of Siberian conifers is that such mulch does not rot for a long time, which cannot be said about straw and similar materials. In the spring, you can add a certain layer. All in all, for mulching and for decorative purposes, a layer of bark or chips with a thickness of 6 - 8 cm is sufficient. In a few years, the lower layer will naturally turn into a natural organic fertilizer.
Application
Mulching is necessary on an unprotected soil surface to restore it or to hide its imperfections.
Mulch can be used in a garden, a summer residence, children's and construction sites, in parks, squares, flower gardens, rockeries, rock gardens, winter gardens, along the banks of reservoirs, swimming pools, for indoor plants and many other places to improve the appearance of the soil and its composition.
Unlike stone and gravel bark, shells and chips can be used as lawns. It is soft and pleasant to walk on such a lawn. Caring for him is minimized: no need to mow, water.
Mulching calculation
1 bag of mulch (50-60 l) is enough for 1 m 2 at a mulching height of 5-6 cm.
Such a simple type of wood waste, like sawdust, finds its application in many areas of life. By themselves, as a material or energy carrier, they are not of great value. But if you force this waste to undergo some processing or a certain technological process with the addition of other components, then the output can be obtained with many useful and inexpensive products or products. In this article, we will tell you what can be made from sawdust and try to cover the most popular ways to effectively use this material.
What is made from sawdust in industrial production?
If you study the issue thoroughly, it turns out that there are a lot of all the ways to use sawdust and it will be difficult to list them in one article. Therefore, we will focus on the most popular options:- Construction Materials;
- various types of biofuels.
Strong and lightweight sawdust concrete is produced in slabs or blocks and is used for the following purposes:
For the device of self-supporting interior partitions instead of more expensive brick ones. In this case, the density of the material is over 500 to 850 kg / m3.
Lighter sawdust blocks with a density of less than 500 kg / m3 serve as insulating and soundproofing elements.
The advantages of wood concrete slabs are low price, low weight and good strength. Disadvantages - inability to withstand the flame for a long time during a fire and high moisture permeability. Because of this, sawdust and cement blocks cannot be used outside the building without a suitable waterproofing layer. Otherwise, the product will become saturated with moisture and lose its thermal insulation properties, and in the cold it will collapse.
Sawdust fuels
Several types of fuel can be made from sawdust. In the factory, solid and liquid biofuels have been produced from them, and for a long time. Solid fuels are successfully burned in the furnaces of various heating boilers, and cars, whose engine is adapted for this, are refueled with liquid fuel. Here is a more accurate list of these fuels:- hydrolysis alcohol (bioethanol);
- wood pellets (pellets);
- fuel briquettes.
Oddly enough, but alcohol is made from sawdust using sulfuric acid. The tree contains cellulose, which, when interacting with dilute sulfuric acid, turns into sugar, and we all know how to get alcohol from it. On an industrial scale, this process is called hydrolysis and takes place in closed vats with a temperature of about 180 ° C and at a pressure of 8-10 bar. In simple terms, the acid solution flows through the sawdust, resulting in a sugar solution. Bioethanol is isolated from the latter by the traditional method - by means of yeast fermentation.
The most advanced solid fuel to date is also made from sawdust. We are talking about pellets, wood cylindrical granules up to 5 cm long and up to 8 mm in diameter. It should be noted that to make steel granules from sawdust in European countries, and then this technology came to us. Their perfection lies in the fact that pellet boilers are fully automated and able to function without human intervention for several days. No other wood-burning heat generator can boast of such a duration of work. Not to mention the efficiency, which reaches 85% for pellet boilers.
Granules are produced on special machines - granulators, which compress the raw material to such an extent that a natural binder, lignin, is released from it. There is only one condition: pellets can be made from raw materials that are crushed to a powder state and dried to a moisture content of no higher than 12%. Therefore, wood waste undergoes a crushing and drying operation. After granulation, strong cylinders are obtained, which allows them to be transported in bulk over considerable distances.
A similar use of sawdust occurs in the production of so-called eurowood or briquettes, in any case, the manufacturing technology is almost the same. The only difference is that the requirements for grinding raw materials are not so high. You may ask: why make briquettes that need to be burned like wood, if there are pellets? The answer is simple: not everyone has access to a pellet boiler, but many have an ordinary stove or a simple heat generator to burn fuel briquettes from sawdust. Moreover, in terms of calorific value, they are not inferior to wood pellets.
Using sawdust at home
In the private sector, there is also a use for wood waste. By the way, small sawdust can also be useful in an apartment, for example, when laying parquet. The fact is that after the installation of parquet boards, gaps inevitably remain between them. So, to eliminate them, it is recommended to prepare filler on sawdust mixed with parquet varnish. The mixture is made to a thick consistency and all the cracks are filled with it. After such an improvised putty has dried, the parquet is sanded with a special machine.Small waste woodworking can be used for the purpose of both insulating and heating the house. This will take time and work, but tangible savings will come out. With the help of sawdust, it is most convenient to insulate the attic floor or the floors of the first floor. Less commonly, they are used for internal wall insulation, filling the cavities between the load-bearing wall and the outer cladding of the house. It should be borne in mind that sawdust insulation loses in terms of thermal insulation properties to such popular materials as foam or mineral wool, but it will cost much less.
To insulate horizontal surfaces, sawdust is mixed with lime and cement, achieving uniformity of the composition, and then water is added. The resulting solution is placed between the floor beams or on the prepared floor surface. Instead of cement, clay is often used, only it is advisable to grind it thoroughly and remove pebbles. Working with any solutions containing small wood waste, the surface is covered with a waterproofing film before laying. In the same way, the laid insulation is covered with a film on top.
All these manipulations are necessary due to the fact that sawdust absorbs moisture well, which cannot be allowed, otherwise their thermal insulation properties are sharply reduced. Similar measures to protect against moisture will also be required in the case when a wall is being erected from sawdust blocks. These can be successfully made at home if you mix wood waste with lime, sand and cement, and then fill the prepared form with this solution. Immediately after setting, the product is removed from the mold and then dried for a long time. Sawdust concrete slabs for wall insulation are made according to the same principle.
Homemade sawdust fuel
Solid fuel from sawdust at home is made only in the form of briquettes. Of course, you can buy equipment and make pellets from sawdust, but such a solution is not economically feasible. In order for the purchased dryer and granulator to pay for itself, you will have to produce most of the pellets with your own hands for the purpose of selling, otherwise it is easier to purchase ready-made pellets for heating.As for the manufacture of briquettes, there are 2 methods used at home. The first is with the help of a small screw press - an extruder, which is most often bought ready-made. Then the technology is almost no different from the production technology, and home-made sawdust briquettes, made by hand, are of good quality and give a lot of heat during combustion. It is clear that significant investments will be required here.
A simpler and cheaper way is to manually make briquettes from a mixture of sawdust and clay, which plays the role of a binder. To compress this mass, home craftsmen use a hand-held machine equipped with a form for storing raw materials. After shaping, the finished products are dried in the open air. Such briquettes are incomparable with factory briquettes in terms of heat transfer, since they have a low density due to the low pressure during compression. Nevertheless, the method has found very widespread use among homeowners who have the raw material in the form of sawdust.
If necessary, charcoal can be made from high-quality handmade briquettes. Traditional methods are used for this - coal is burned in pits or barrels, and then sorted and packed in bags.
Other areas of application of sawdust
It is rather difficult to list everything that can still be made from sawdust in the household, we will give just a few examples. One option is to make insulation mats for a variety of purposes, such as wrapping water pipes and other pipes that are laid above ground level. But, again, good waterproofing of such mats is necessary. In another case, sawdust is used as mulch in the vegetable garden or in the garden. To do this, they are poured over the soil with a layer of 4-5 cm, which makes it possible to retain moisture in it for a long time and prevent weeds from germinating.Sawdust is a great help when you need to arrange bedding for pets and poultry. Since they absorb moisture well, the litter stays dry for a long time. In an apartment, sawdust is also used as a filler for cat or dog toilets. And finally, one cannot fail to mention all sorts of souvenirs and homemade toys filled with sawdust. Children like these crafts in the form of toys, and pictures from colored sawdust can add a special charm to the interior of your home.
As it turned out, small wood waste is a very versatile material. The range of application of sawdust is very wide, they are used for various purposes both in the household and as a raw material for the production of thermal insulation products and fuel.
For example, from a furniture production or a carpentry workshop, an enterprising owner asks the question - what can be made from sawdust. The answer will depend on how exactly he wants to use them. With artistic talent, sawdust and shavings can be excellent material for creative ideas. And if you have a private house, dacha or livestock farm, then wood waste will serve as an excellent help in the garden or in the garden, on the farm or in the chicken coop.
Businessmen can be advised to start producing fuel or building briquettes. You will learn useful tips and ideas for a private business from the article. In it, we will look at simple examples of what you can do from sawdust with your own hands at home.
Litter in animal husbandry
Sawdust and small shavings perfectly absorb moisture and biological waste. They are poured onto the floor for cows, pigs, horses and other domestic animals. According to farmers, too small sawdust is harder to remove, but it absorbs liquids better. And large sawdust and shavings do not cope well with the task, and they need to be laid on the surface in a large layer. Therefore, it is advised to make a mixture.
The best thing you can do with sawdust for quality bedding is to add some fermentation materials to the mix. They remove unpleasant odors and even generate heat, which will save fuel for heating in the cold season.
Use for vegetable gardens
Let's look at what can be made from Gardeners have long been using them to mulch trees, sprinkling circles around them. It is also convenient to cover the soil in vegetable gardens and greenhouses with sawdust and small shavings. They protect it from freezing, help to retain moisture after watering. Also, the litter on the ground prevents weeds from germinating, and a dry crust does not form on the soil surface. Thus, the compaction of the land does not occur, and this is of great importance for the quality growth of garden and berry crops.
A layer of sawdust on the site reduces the effect of cold air on the roots, does not allow wind and water to wash out beneficial nutrients from the soil layers.
Now you know what can be made from sawdust, but there is one little secret. It is best to use stale shavings for farming, as otherwise they slowly mineralize and can at the same time consume a lot of nutrients from the ground, thereby taking them away from garden plants and acidifying the soil. It is advisable to first let them peel in a compost pit, sometimes turning them over with a shovel. In this case, sawdust can be poured onto the surface of the flower beds and even into pots with indoor flowers. They will only fertilize the land, and the plants will give a greater yield.
What can be made from sawdust and shavings was invented by the inhabitants of North America. In Guatemala, there is a place called Antigua, where Easter is celebrated lavishly every year. On Holy Week, a huge number of believers gather in the village, who come from all over the country to watch bright processions and interesting performances of old events that happened to Jesus Christ.
Anyone can take part in an extraordinary action right on the streets of the city, namely, create a carpet of sawdust dyed in different colors on the road. They are carefully sifted, stencils are made, and sometimes canvases are laid under the drawing. Some people add real flowers and green leaves of plants to carpet patterns.
Prepare for the procession of believers 12 hours before its start. Subsequently, the entire ceremony progresses through the streets, stepping on these works of art. Some people make such carpets in their yard or even in their apartment. People convey their religious feelings through drawings and ornaments.
Papier-mâché material
We are all accustomed to the fact that traditional papier-mâché is made of paper, but if you think about what can be made from sawdust, the answer is - the same papier-mâché. To create a thick mass, select a small material and add PVA glue to it. After thorough kneading, a dense plastic consistency is obtained, which is perfectly molded.
It can be used to make masks and small sculptures on a solid base. After hardening, such papier-mâché is quite strong, it can be painted with acrylic paints and varnished.
Crafts from wood paste
You already understood what can be made from PVA glue and sawdust, but you need to know the exact recipes for making wood paste for modeling, so that the figures and other crafts are durable and do not crumble after drying.
Let's consider some of them:
- 2 tbsp. sawdust, 1 tbsp. wheat flour, the same amount of starch, a teaspoon of PVA and 1 glass of cold water. Mix all dry ingredients in a separate bowl. Dissolve the glue in water and pour in a little to the rest of the ingredients, stirring constantly.
- 2 glasses of fine sawdust from the saw, 1 glass of wallpaper glue, mixed in the same amount of water. For complete dissolution, you will have to wait 10 minutes. Then mix everything with sawdust, but not immediately, but adding liquid in parts, while stirring all the time.
After making a dense mass, you can sculpt crafts, like from plasticine. To dry, cover the work with a cloth and leave in a dry place for a day. Do not expose to the open sun, so as not to get cracks. If the work is bulky, flip it from side to side several times to dry evenly on all sides.
Tableware decoration
Let's see what else can be made from sawdust. Dishes on which curly patterns are applied looks beautiful, as in the photo below. To make such beauty, the smallest sawdust is taken, resembling dust. Then you can act in different ways. First, create the desired pattern on glass or clay using PVA glue with a brush, and sprinkle sawdust on top of it. Lightly press down the drawing with a napkin or directly with your hand, and pour excess sawdust onto the table surface.
You can do it differently. First, mix a couple of tablespoons of PVA with sawdust in a container, achieving the consistency of sour cream, and apply strips to the object of creativity with a brush. Do not forget that all drawings are done only on the front side, if you want to use the dishes in the future.
Cottage decoration
Knowing the recipes for preparing wood pulp and having several molds, you can make decorative tiles to decorate the walls or floor of a house on a personal plot. Such a design technique will be the answer to the question of what can be done with sawdust in the country. After all, you must agree that the same tiles will look beautiful both on the wall and on the floor of the room.
With their help, by the way, you can update the surface of an old table or cabinet, putty with a mass of holes or cracks in the floor and on furniture. Using small sawdust with the addition of chips or shavings from different types of wood, you can diversify the look of your work.
Briquettes for space heating
In connection with the latest trends in the rise in prices for different types of heating fuel, many are wondering what can be done from wood chips and sawdust. This is a cheap waste material that will be gladly sold for a penny both in private carpentry workshops and in furniture factories that do not make chipboard.
You can, of course, use ordinary sawdust by pouring them into the boiler. They will also give heat, but the efficiency will be much lower. Therefore, some entrepreneurs are engaged in pressing them into briquettes. If you wish, you can do them at home using a homemade press. On an industrial scale in production, such fuel briquettes are made on granulators. In your household, it is important to choose sawdust of the same consistency, you can add 10% clay, mix all this with water and dry the mass in the sun. Briquettes can be squeezed out through a hand press, or they can be laid out in small molds. In any case, they will provide an excellent thermal effect on cold winter days.
What can be made and sold from sawdust
A wonderful warm and light home is obtained from the so-called wood concrete. Some have not even heard of such material, but wood concrete blocks have been used for a long time, even several rooms at Antarctic stations have been built from them. The blocks resemble large bricks that are easy to transport and carry. They can be quickly adjusted to any size with a simple saw. Screws are well screwed into the finished walls and nails are hammered, they are warm and breathable, environmentally friendly and strong. Their surface can be plastered like ordinary bricks.
For the production of wood concrete blocks, chips of coniferous trees, such as pine, Christmas tree or fir, are used. Also, good material for blocks is obtained from poplar, birch and aspen chips. You cannot take only beech and larch!
First, all wood is disinfected so as not to cause fermentation processes when mixed with water and cement. From this, voids or swelling of the material may appear. Chemical treatment is carried out using a mixture of calcium chloride with water glass and aluminum sulphate. In addition, the chips are additionally treated with an antiseptic to get rid of insects and bacteria.
Only after preliminary preparation, a plasticizer (1% by weight) and Portland cement (up to 15%) are added to the sawdust. Then the resulting mass is molded and dried for at least 2 days at a temperature of 60 ° C.
As you can see, the use of sawdust can be found in a variety of ways. This is an excellent material for both creativity and construction and household work.
We got a log, a bar, boards from a tree, the croaker went to the construction of scaffolding ... But what about the whips, twigs, branches, bark? What to do with soft mountains of shavings and caked dunes of sawdust? After all, this is also wood, and the greater the output of finished products from it, the more profitable it is. So there is such a thing as chopped wood. Moreover, partly it is a by-product, a semi-finished product for obtaining something, and partly it is produced as a special commercial product. Chopped wood includesprocess chips, shreds, wood shavings, sawdust, wood dust and wood flour.
Wood chips and crushed and products from them
It is obtained from both wood waste and solid wood. It is used both as fuel and as mulch in the garden, and to improve the taste and aesthetic qualities of food and drinks (alder for smoking, oak for aging cognacs). Technological chips are used as a raw material in the pulp and paper industry and for the production of hydrolysis alcohol.In construction, wood chips are used to obtain wood concrete (concrete with wood - so it is warmer and you can even drive a nail into it). Also, chips are massively used to obtain building materials such as chipboard and fiberboard. Chip thickness for any use does not exceed 5 mm , length: maximum - upon receipt of chipboard (up to 60 mm ), the smallest one is in the technological one (about 5 mm).
The use of the shredded material is almost the same as the use of wood chipsThe difference is in receiving: chips are obtained by splitting, crushed- on hammer mills and crushers.
Application of wood shavings
Usually it is obtained by planing, most often from soft or softwood.According to the production technology, two types can be distinguished: specially prepared shavings and waste shavings. Its dimensions depend on the purpose. For example, to pack eggs, you need large chips, for packing apples - thin and narrow. In general, the size of the chips varies within the following limits: thickness - 0.05- 0.5 mm, width - 2-8 mm, length - 200-530 mm.
It is used in agriculture for bedding, and in the furniture industry for the manufacture of chipboard, and as a container and fuel. But we are more interested in construction applications: acoustic and heat-insulating cement-particle boards are made from it, which are lightweight concrete, that is, arbolite.
Sawdust and their use
Sawdust can generally be called a waste, but very valuable raw material. And where are they not only used? Cellulose, cardboard, paper, hydrolysis alcohol are also sawdust.Clean the fur, please. Spreading cattle - no problem. Insulate strawberries for the winter, and in a rainy summer, saving them from sand is easy with sawdust. Getting compost or mulching the soil with sawdust will not be difficult. Filter wastewater - and here sawdust does not poorly cope: it is twice as good as activated carbon.
They are also irreplaceable in construction. Plates made from sawdust with shavings by the extrusion method (punching) have increased wear resistance and hardness. If xylene waste is added to the sawdust before pressing, the slabs become fireproof and frost-resistant.
Sawdust is a good heat insulator, and not necessarily in the form of a filler in mixtures and solutions, but also in a loose state. For example, mansions are now insulated like this: the inner masonry is made of porous concrete, the outer one is made of bricks, between them there is an air gap, usually covered with dry sawdust.
Wood dust and flour
Wood dust consists of 15-20 micron wood particles. It is formed during the processing of wood. Although it forms in any woodworking process, it is most often a byproduct of sanding furniture. Although it can be used, for example, as a filler in composite materials, this does not happen often. They simply do not want to get involved with it: there is no industrial volume of its production, and by itself it is explosive.
Wood flour is produced specially by grinding dry wood. Basically, the raw material for its production is dry shavings. Its size and particle size distribution are regulated by GOST. Wood flour has found application in petrochemistry, in the production of fine-ceramic filters, in the manufacture of composites. At a construction site, it is important to use it to obtain grinding, polishing and dry mixes, as well as linoleum.