Build Daily

August 12, 2017 18:06

Pellets with their hands

One of the modern species solid fuel stoves, fireplaces or heating boiler houses are pellets - compressed mini-briquettes, which is obtained from the waste timber and wood-processing industry . Thus, solves two important problems - providing consumers with fuel and rational utilization of waste, that used often simply burned without any benefit .

Pellets with their hands

Pellets with their hands

Pellets very convenient to use, especially because specifically for this type of fuel designed boilers, equipped roomy bunkers download and lines of automatic continuous feed pellets into the combustion chamber (for more detailsYou can learn of the relevant publication of our portal ).Many models of these heaters are designed for home use in a self-contained heating systems of private houses.It is therefore quite understandable growing interest owners of private housing to issues of search reliable suppliers of this type of fuel.Many homeowners, not only think about whether it is possible to produce pe

llets own hands.

This article will address the main advantages of granulated solid fuels, process steps of the process of its production and the necessary equipment.Those readers who are willing to make pellets their hands must realistically assess available opportunity to weigh «for» and «against» , to ensure rationality and economic feasibility of such an approach to the problem of self-sustaining own housing granular fuel.

What pellets and their main dignity

Article Contents

  • 1 What are pellets and their main advantages
  • 2 What is
    • technological pellet manufacturing process2.1 Video: full production of pellets production cycle
  • 3 pellet production in
      private households
    • 3.1 Video: homemade drum dryer from the barrels
  • 4 What is necessary for the independent production granulator
    • 4.1 Video: device compact granulator pellet
    • 4.2 Video: how to make a matrix
    • 4.3 Video: work a small-sized installations for the production of pellets
    • 4.4 Video: homemade installation screw type for pellets

compacted pellets called mini-pellets (pellet) cylindrical shape with a diameter of 4 to 8 ÷ 10 mm, length usually from 15 to 50 mm. raw material for their production can be a variety of materials.

In a variety of materials can be used as raw material for the production of pellets

as a raw material for the production of pellets can be used a variety of materials

  • Most often used for granulation of waste wood processing enterprises - sawdust or fine shavings.Similar pellets are the highest quality.
  • in recycling and waste allowed logging and primary wood processing - bark, branches, and even dried leaves or needles.
  • actively used as raw material waste agro-technology - straw, sunflower husks, bagasse, grain wastes , remaining after milling lines or the production of cereals.
  • Do pellets from peat - in such a this type of fuel will provide maximum energy efficiency.
  • In large poultry farms often set line for the production of pellets their chicken litter - the problems are solved and disposal and disposability production.
  • Modern technologies of processing allow you to apply for the production of pellets even sorted municipal solid waste.

course, pellets , made of various materials, seriously different quality and their potential energy efficiency.Accepted distinguish three main types of such granular fuel:

The pellets themselves may be different quality class

pellets themselves may be different quality class

  • optimal for use are considered pellets «premium» in the autonomous heating systems.They are made entirely of wood waste with a high degree of purification.They are distinguished by a pronounced light shade and uniformity of structure.Such pellets minimum percentage of ash - the residue fireproof is to just 0,5 % of the total mass of fuel.The vast majority of manufactured for mass consumption pellets refer precisely to this class.Perhaps the only significant disadvantage of such a fuel is its fairly high price.
  • Pellets so-called industrial (industrial) varieties may include in its membership certain small percentage of bark particles, ground impurities, leaves or needles. Ash have certainly much more, but energy intensity is still high enough that gives the opportunity to apply them in a home heating system, provided more frequent maintenance work on the boiler equipment.But the cost of such fuels have significantly lower.In color they are noticeably darker pellets «premium».
  • Most low-grade pellets on an industrial scale is obtained from agricultural waste and other materials.The level of ash from them is very high - up to 4 % and even more, they do not differ, and large power consumption . Nevertheless , the low price makes it cost-effective to use them in large boilers.

Incidentally, some species pellets can be used not only as a fuel for combustion in furnaces and boilers. They are used, for example, fertilizers and mulch, as adsorbents and fillers "cat litter".

What is positive qualities still have pellets :

During the combustion of the pellets into the atmosphere harmless substances involved in the natural exchange

During the combustion of pellets into the atmosphere harmless substances involved in the natural exchange

  • They are among the most environmentally friendly fuels - harmful and active substances in the wastegases is minimal.Basically it - water vapor and carbon dioxide, which are easily absorbed by plants.
  • pellet fuel perfectly amenable pyrolysis, and this gives able to apply it to the appropriate high-performance boilers long burning.Using lines automatic loading to minimize human involvement in the process of boiler equipment.
  • This fuel is very compact and does not require a large space for the organization of its storage.It is much less expensive and would require transportation required fuel reserves.
Pellets are easy to transport and storage

Pellets are easy to transport and storage

  • When making pellets does not apply any chemical additives, adhesives and mixtures of modifiers. They have no unpleasant odors are not able to cause allergic reactions, and x x injury can be arranged even in the immediate vicinity of the premises.
  • heat dissipation quality pellets, especially in volume ratio, superior to most conventional types of wood and coal.
  • Pellets not subject to internal processes of decay or debate.This virtually eliminates the possibility of self-ignition.
  • Quite often pellets are the most inexpensive and view high-quality fuel in the region, especially if there manufacturing enterprises engaged in their manufacture - is possible to conclude long-term contracts for certain volumes wholesale deliveries.

In than is process manufacturing pellets

whole technological process for the production of granular solid fuel is divided into several stages.

Scheme of technological stages of production of pellets

scheme of technological stages of production of pellets

  • Initial training and primary crushing of raw materials.Wood, agricultural waste or possibly sorted, cleaned of unwanted impurities and transmitted to the primary crushing material line.
Stationary crusher for primary crushing of wood

stationary crusher for primary crushing of wood

Conventional crushers, fixed or mobile, used by logging companies or timber , and sometimes there are in private households, provide output chips of 30 - 50 mm, thickness 1 - 2 mm.

  • next required step - drying crushed material.To further manufacturing process is required that the residual humidity of the wood does not exceed 12 ÷ 14 percent.For this raw materials sent to the dryers, drum aeration or principle of action.
The dryer aerodynamic principle of action

drying plant operating principle of aerodynamic

  • dried wood transferred to fine grinding line.Most often, hammer mills are used here (mills), which is adjusted to the condition of small chips or sawdust, "wood flour".Maximum wood particle fraction at the output should not exceed 4 mm.The usual density of the material at the exit of the production line is about 150 kg / m³.
Hammer Mill brings the raw materials to the required fines

Hammer Mill brings the raw materials to the required fines

  • often happens that after drying and grinding the final residual moisture in the raw material crushed will not be enough to form strong pellets.To resolve this issue and bring the humidity to the required 10 ÷ 12 per cent, water treatment spend cycle - raw material saturated with hot steam or plain water. Steam apply in the case of using as wood raw material solid rocks or old, had lain for several years.For the softer grades are commonly used immersion in water.
  • After achieved the required humidity, raw transferred to the pressing line.In special installations is forced through a matrix having a cone-shaped hole certain diameter.The special shape of the channel helps to maximize seal sawdust. addition, under the influence of pressure and the inevitable rise in temperature, the wood a special ingredient - lignin, which is always included in the its biochemical composition.Lignin promotes lasting gluing tiny pieces in a sufficiently dense structure pellets .
The shaped pellets downstream of a cylindrical matrix

molded pellets at the outlet of the cylindrical matrix

Matrix can be cylindrical or flat type. Raw , compressed into cylindrical pellets, for every complete rotation of the matrix is ​​cut with a special knife, thus achieving an approximate observance of uniform linear dimensions obtained pellets.

Approximate pellet compression scheme through a cylindrical die

exemplary pellet compression scheme through a cylindrical die

Cylindrical matrix are most often used in stationary industrial plants . The compact models granulators preference is given to flat die with two or more rollers.

The small plants are more commonly used round flat matrix

In small plants are more commonly used round flat matrix

  • obtained at the outlet from the press line pellets cooled, as they may have a temperature of 65 ÷ 90 degrees, dried naturally and then packed in sacksand sent to the warehouse of finished products to retailers or directly to consumers.

Video: full production manufacturing pellets cycle

production pellets in private households

What seems simple enough in the industrial production of granulated fuel, farIt will not always be possible or cost-effective when trying to organize a similar scale in the private sector.The problems lie in the following:

  • To produce pellets is mandatory presence of specialized equipment - granulator.Such a small installation performance produced by some companies (European and Chinese), but their cost - is quite high, sometimes up to several hundred thousand.You can order a similar machine and private craftsmen, who have mastered the production of such technology - the internet offers a lot. Nevertheless , and individually manufactured high-quality equipment is, perhaps, no less factory.

In numerous articles on various sites you can find the assertion that this equipment is easy to make their own.It is not clear what guided the authors of such publications, drawing such a rosy picture.Granulator, indeed, can be done yourself, but this simple process can not be called.Preparation of necessary parts, assembly of the rotation transmission mechanism, the precise fit of all moving parts with regard huge loads encountered in the process of granulation - a high degree of complexity of the task, the available masters, well-versed in the properties of metals and their processing technologies.It will take high-precision turning, milling, welding, plumbing work, requiring a real, professional qualifications. Before undertake manufacturing, must be very sober assessment of their capabilities.

  • second important aspect - availability of raw materials.If you plan to manufacture homemade pellets, as they say, «from scratch», the required installation material crushing and drying mandatory.Will it be cost-effective even from the point of view is not the acquisition of equipment and enegrozatratnosti all processes?When mass production is paying off large quantities of processed products, and to ensure that the needs of individual farms may arise and a negative balance.

probably take up manufacturing pellets in the home it is advisable in case there is a possibility of regular and virtually free of receipt of the finished raw materials - crushed chips or sawdust.Then, it may be beneficial not only to supply himself with granulated fuel, but also to offer finished products for sale to other homeowners.

By the way, many granulating apparatuses flat die is not required secondary crushing cycle - will cope with this heavy powerful toothed rollers that need to grind the chips to a condition suitable for pressing pellets.Without drying of wood chips, however, all too early in most cases it is impossible to do, but resourceful craftsmen make simple drum dryer using the old metal barrels.

Video: homemade drum dryer from barrels

  • should be noted that not every timber is fully suited for the production of pellets .For example, almost doomed to failure attempts granulated sawdust from a linden, willow or poplar - bad stuff "baked" and crumbles at the slightest mechanical stress.

optimal for these purposes is considered softwood - its natural gummosity helps to ensure a stable solid granules.