EA035557B1 - Incinerator for destroying documents - Google Patents

Abstract

The invention relates to devices for eliminating waste documents using fire. An incinerator comprises a housing with a flue pipe and a charging door, an ash box, and a document distributing and feeding device, which comprises side walls of the housing and a double-pitched conduit with air ducts in the base for primary and secondary air, said conduit being arranged at an incline between the front and rear walls of the housing above a grate system, which comprises grating plates connected to a ridged grate to from a W-shape and tubular grates which can be mounted vertically above openings in the joints between the plates and the ridged grate. The plates are mounted at an angle of from 40 to 45° to a horizontal plane and are provided with openings which are closed by arcuate members. The invention allows to reduce the volume of additional fuel necessary for burning documents, increase the level of automation of a burning process, simplify and reduce the cost of the incinerator design.

Description

SUBSTANCE: invention relates to devices for waste disposal of document circulation by fire method and can be used for guaranteed destruction of documents of various formats, stitched or from separate sheets and other forms of printed publications.

Currently, there are several ways to destroy documents [1]. One of the simplest and relatively inexpensive ways to destroy documents is to bury them in the ground. However, this method does not provide the required degree of reliability for the destruction of information contained in documents, therefore, it does not find practical application.

There is a known method of disposal [1, 2], based on shredding (shredding) documents to sizes that exclude the possibility of subsequent recovery of the information contained in the documents by third parties. This method is implemented in a variety of designs, however, the disadvantage of all these designs is that they can shred documents only from separate sheets, and are not suitable for destroying bound documents or books. Structures suitable for the destruction of these documents in this way are so energy-intensive that they become uncompetitive in comparison with structures that implement other methods.

There is also known a method [1, 3], based on the chemical processing of documents. With the help of chemical treatment, the paper softens and turns into paper pulp. This method is distinguished by a high level of reliability of information destruction, however, it has a high cost of destruction of a unit of mass of documents, therefore at this stage it is mainly used only as an additional security measure when destroying paper documents using shredders. In addition, chemical destruction of documents requires a lot of time, during which unauthorized access by third parties to the destroyed documents is possible.

A well-known method of guaranteed destruction of documents based on their burning in various furnaces using additional fuel [1, 4]. The disadvantage of the known designs that implement this method is the need to use significant amounts of additional fuel, which leads to an increase in the cost of the destruction of documents. In addition, such ovens are expensive and require specialized premises for their operation, which significantly limits the scope of their practical use in organizations and institutions in need of such a device.

The closest analogue of the invention is an incinerator furnace for the destruction of waste or documents [5], selected as a prototype, which contains a body with a chimney, non-sink grates, arranged in steps one above the other with a vertical gap, under which through the air duct using a blower fan air is supplied, and a gas or diesel burner is placed in the housing on the opposite side of the grate plates. After loading through the loading door into the furnace of waste or documents, air is injected onto the grate plates under them (with the possibility of its redistribution under the plates), and from the opposite side a jet of fuel is supplied, in the flame of which documents are gradually burned, the ash and ash from which is displaced with a scraper into the ash box. The main disadvantage of the known furnace is the need to use additional fuel, since documents and other printed publications relate to hardly combustible fuels. In addition, this furnace requires the constant presence of an operator who moves the fuel along the grate plates, regulates the air supply to the places of the plates where the combustion process is slowed down.

The objective and technical result of the invention is to reduce the volume of additional fuel required for burning documents (additional fuel serves only to ignite the furnace and its amount does not depend on the volume of destroyed documents), automating the combustion process, simplifying and reducing the cost of the furnace design.

The essence of the invention

The solution to the problem and the achievement of the technical result is provided by the fact that the incinerator oven for burning documents contains a housing with a chimney, a loading door, grate plates with an air cavity located under them.

According to the invention, the incinerator furnace further comprises a document distribution and feeding device comprising side walls of the housing and a gable tunnel with primary and secondary air ducts at the base, located with a slope between the front and rear walls of the housing above the grate system. The grate system includes W-shaped grates with a ridge grate and pipe grates. The pipe grates are installed vertically above the holes at the joints of the plates and the ridge grate. In this case, the slabs are installed at an angle of 40 to 45 ° relative to the horizontal plane and holes are made in them, closed by arched plates. The total area of the holes is made in the range from 15 to 17% of the cross-sectional area of the primary air duct. The primary air duct has a damper on one side, and on the other, it is connected by a section of the duct with the underglass cavity and the secondary air duct. The area of the opening in the secondary air duct is 20 to 25% of the cross-sectional area of the primary air duct. In the side and upper walls of the secondary air duct, holes are made with a total area of 20 to 25% of the cross-sectional area of the primary air duct

- 1,035557 spirit. In pipe grates, plugged from above, on the side surface on one side there are holes facing towards the plates. The total area of these holes is 10 to 12% of the area of the primary air duct. The area of the openings between the plates and the ridge grate is from 25 to 30% of the area of the primary air duct. The end of the chimney pipe is passed inside the tunnel and fixed to it. Along the side surfaces of the tunnel above the secondary air duct, holes are made with a total area equal to the cross-sectional area of the chimney.

The essence of the invention is illustrated by the drawings shown in FIG. 1 and 2, which show a cross section and a longitudinal section of a document incinerator, respectively. FIG. 1, 2 denoted: housing 1, chimney 2, loading door 3, gable tunnel consisting of an upper gable cover 4 and side walls 5, holes 6 in the side walls 5, primary air duct 7, damper 8, secondary air duct 9, holes 10 and 11 from the secondary air duct 9, gapless grate plates 12, holes in plates 13, arched plates 14, ridge grate 15 with holes 16, pipe grates 17 with holes 18 on the side, ignition door 19, cleaning door 20, ash drawer 21.

The body 1 of the incinerator-incinerator for incineration of documents is made of steel, thick and heat-resistant to ensure the operation of the furnace for the required period. The same requirements for metal are imposed on the rest of the furnace elements and have no fundamental differences from the known designs of furnaces of similar power. With an increase in the size of the furnace to strengthen the body 1, it can be additionally finned. The ribs in this case also increase the heat exchange surface of the case, improving its cooling. To ensure the operation of the furnace in various climatic and meteorological conditions, a casing can be installed on the body 1 with a gap. For the operation of the stove outdoors and in the open area, the casing is made from the sides and from above in the form of a lid that can be removed or opened after ignition of the stove. In this case, the casing makes it possible to ignite the furnace much faster, especially at low ambient temperatures or the presence of precipitation. When operating the furnace inside the room, the casing is made from all sides and is equipped with a discharge pipe under the air casing and a pipe for removing heated air outside the room. To exclude unauthorized access to the destroyed especially important documents during their burning, the furnace can be equipped from the front panel with a two-leaf or one-leaf metal door with a lock (with the necessary level of secrecy), which guarantees unauthorized access to all the furnace doors. In this case, gaps or holes are made at the top and bottom of the door for the passage of air cooling the body. The oven can also be equipped with a thermostat that maintains the heat output of the oven within optimal limits. Therefore, the stove can function autonomously for the entire period from ignition to completion of combustion. Chimney 2 is made of a steel pipe, the diameter of which is selected based on the capacity of the furnace (usually in the range of 220-350 mm). Chimney 2 is hermetically attached to the body 1 and to the gable cover of the tunnel 4. The distance from the upper cover of the secondary air duct 9 to the inlet of the chimney should be within (1.11.3) D / 4, where D is the diameter of the chimney. Requirements for the height of the chimney, its structure, including thermal insulation, do not go beyond the requirements for chimneys of well-known stoves with a thermal power of about 100-200 kW. The loading door 3, the door for ignition 19 and the door for cleaning the furnace 20 can be made of steel or cast iron and have no fundamental features in the described design. The gable tunnel, consisting of a gable cover 4 and side walls 5, together with the side walls of the body, is designed to distribute and automatically feed the loaded documents into the combustion chamber. The gable cover 4 has a slope towards the rear wall in order to more evenly distribute the documents along the oven when loading. The angle between the sides of the cover should be 100-120 °. In the side walls of the tunnel 5 above the secondary air duct 9 above the holes 11 and near the rear wall of the housing 1 there are holes 6 (of arbitrary shape) for the passage of flue gases with a total area approximately equal to the cross-sectional area of the chimney. In this case, the area of the holes 6 near the rear wall of the housing 1 is about 60% of the cross-sectional area of the chimney. The bottom edge of the holes 6 must be below the base of the chimney. Opposite to the holes 6 near the rear wall of the housing 1 and between the holes 6 and 11 along the walls 5, abutments made of a strip or a rod (not shown in the drawing) are vertically installed to prevent the holes 6 from being blocked by separate documents. At the base of the tunnel there are air ducts of primary air 7, and above it of secondary air 9. Air duct 7 has a shutter 8 at the inlet end. The other end of the horizontal part of the air duct 7 is connected through a hole with the secondary air duct 9 and through the vertical part with under the grate air cavity. The cross-sectional area of the primary air duct is approximately equal to the cross-sectional area of the chimney. The area of the hole from the air duct 7 to the air duct 9 is 20 to 25% of the cross-sectional area of the air duct 7. For additional heating of the passing air, the lower wall of the air duct 7 is located above the lower edge of the side plates 5 of the tunnel. As a result, a cavity is formed under the air duct, in which hot flue gases are retained, heating the air in the air duct 7. The damper 8 can be controlled both manually with fixing the required position, and automatically from a thermostat (not shown in the drawing). As a thermostat can be used, for example, a thermostat, whose operation is based on the use of a linear expansion

- 2 035557 of the furnace body on the temperature relative to the heat-insulated reference rods and transmission through the lever mechanism of the linear expansion of the body 1 to the damper drive 8. The secondary air duct 9 serves to channel the secondary air into the cavity inside the tunnel, through holes 10 and on the side of the tunnel, through holes 11 , which is used for afterburning the pyrolysis gases formed in the furnace and on the surface layers of the entire volume of documents. The total area of the holes from the secondary air duct 9 is from 20 to 25% of the cross-sectional area of the primary air duct 7. The holes are made evenly (several holes) along the upper plate of the secondary air duct 9 and in the side walls 5 of the tunnel under the holes 6. The ratio of the hole areas from the secondary air duct into the tunnel and outside it is approximately 1: 3.

The grate system of the furnace consists of no-sink plates 12, ridge grate 15 and pipe grates 17. Plates 12 are attached to the side, front and rear surfaces of the body 1 at an angle of 4045 ° relative to the horizontal plane and are connected in a W-shape with the ridge grate 15. In plates 12 holes 13 with a total area of about 15-17% of the cross-sectional area of the primary air duct. The holes 13 are covered with arched plates 14 to prevent them from overlapping by documents in the process of their displacement along the plates. In this case, the area of the side sections under the arched plate should be greater than or equal to the area of the hole. The ridge grate 15 is a plate bent at an angle of about 120 °, the ends of which are bent at an angle of about 150 °. These ends of the ridge grate are connected to the plates 12. Also at these ends of the ridge grate, holes 16 are made with a total area of 25 to 30% of the cross-sectional area of the primary air duct. Above these holes, pipe grates 17 are installed, which consist of sections of cylindrical or shaped pipes, plugged in the upper part. On the side surface of the pipes 17 on one side there are holes 18 with a total area of 10 to 12% of the cross-sectional area of the primary air duct. Pipes 12 are installed vertically above the holes 16 between the ridge grate 15 and the plates 12, the holes directed towards the plates 12. When using shaped tubes, for example square ones, on the side where the holes are made, a stop made of a bar or strip of metal is installed to prevent overlapping of the holes 12 documents sliding down the slabs. The height of the pipes is chosen from the expression Нтр = 1.1 B / Sin (90-a), where B is the shortest distance between the plate and the lower edge of the side wall 5, α is the angle of inclination of the plates 12. Ash box 21 is installed in the under-grate air cavity, used for its intended purpose and has no peculiarities.

The incinerator-incinerator for incineration of documents operates as follows.

The oven is loaded with documents subject to guaranteed destruction (separate and bound sheets, magazines, brochures, books and other samples of printed products of various formats) through the loading door 3. In this case, the first documents from the batch are rolled along the cover 4 of the gable tunnel, between the side walls of the body and the walls 5 tunnels and slabs 12 to pipe grates 17, resting against them. Subsequent documents randomly fall on each other (with air cavities between individual copies), filling the space on plates 12, between the side walls of housing 1 and walls 5 of the tunnel and on its cover 4. After loading the entire volume of documents planned for destruction, door 3 is closed. Next, the door for ignition 19 opens and a small amount of solid fuel, such as firewood, is loaded onto the ridge grate 15. Crumpled sheets of paper or documents can be used in part. The damper 8 is closed and the fuel is ignited. After chimney 2 warms up and a stable draft appears in it, door 19 closes (all other doors must also be tightly closed), and damper 8 opens. In this case, the air, passing through the air duct 7, heats up to a high temperature and enters the grate cavity, where it additionally heats all the elements of the grate system. Hot air from this cavity enters the furnace through holes 13 in plates 12, holes 18 in pipe grates 17 and holes 16 between plates 12 and ridge grate 15. The area of these holes and their ratio between themselves and the cross-sectional area of the primary air duct are selected in such a way so that the speed of the air exiting the indicated openings is significantly higher than the flow rate of the flue gases. The combination of high air temperature, high speed of its movement and impact from several directions contribute to loosening of paper and documents, their ignition and vigorous combustion. In this case, hot flue gases through the air cavities between the documents and through the slots, between the side walls 5 of the tunnel, the stops and the documents adjacent to them rise under the upper cover of the housing 1, gradually cooling down, falling down, falling into the holes 6 of the tunnel (mainly in the holes 6 near rear wall of the housing 1), from which they exit through the chimney. Part of the flue gases, passing by the holes 6, immediately enters the tunnel and then goes into the chimney 2. When the documents are heated above 100 °, the process of formation of pyrolysis gases begins, which are burned out when passing by the holes 11, due to the supply of secondary air from the air duct 9. Part flue gases enter the holes 6 due to the draft in the chimney, and part of it passes higher along the side walls 5 of the tunnel, rising under the cover of the housing 1. That part of the pyrolysis gases that forms outside the furnace, mainly on the surface layers of documents, getting into the tunnel with flue gases , is burned out under the tunnel cover 4 due to the supply of secondary air through the holes

- 3 035557 from the air duct 9. It should be noted that since the documents lying on the plates 12 between the walls 5 of the tunnel and the side walls of the housing 1 have the same inclination as the plates, the flue gases from the furnace through the air cavities between the documents also move to the side to the walls of the case 1. In this case, additional heating of the bulk of the documents occurs, which contributes to their better combustion and the formation of pyrolysis gases. The thermal energy generated in the listed processes is dissipated (by radiation and convection) into the surrounding space by the furnace body, another part is carried out through the chimney with flue gases, and the rest is used to support the process of burning paper documents by heating the primary and secondary air and the documents themselves. It should be noted that with this path of movement of flue gases, separate parts of the sheets of documents that have not been burnt out at once, if they are picked up by an ascending stream of hot flue gases, have time to completely burn out along the path of movement of flue gases, since they, rising under the top cover of the case, circulate there for some time gradually cooling down. Therefore, at the outlet of the chimney, the removal of unburned pieces of sheets of documents with flue gases is practically excluded. Thus, a complete guarantee of the destruction of the documents and information contained in them is achieved. As the documents lying on the grate system burn out, the documents located above are displaced under their own weight along the inclined surface of the plates 12 downward, taking their place. The specificity of burning paper documents as a fuel is that the fire cannot independently spread inside tightly packed (bound, glued on one side) sheets of paper. Therefore, the burning of documents occurs mainly on the grate system due to the action of jets of hot air, under the influence of which there is a partial release from the ash of the surface layer, loosening, ignition and burning of paper. Thus, a self-sustaining process of sequential burning of a large mass of documents (up to several hundred kilograms) is provided. Due to the organization of such a distribution process and the gradual filing of documents into the grate system, the thermal power of the furnace, as a rule, remains at approximately the same level. However, in practice, situations may arise (high ambient temperature, low humidity of documents, not dense stacking, increased draft in the chimney and other factors), the heat output of the furnace may increase above the permissible limit (the body temperature will exceed 500 ° C). In this case, the operator closes the damper 8, limiting the flow of air into the furnace. Due to this, the intensity of combustion decreases, the released heat power decreases and the temperature of the furnace body decreases. When using the above thermostat in the oven, the heat output is automatically adjusted within small limits without operator intervention.

The end of combustion is indicated by a decrease in the temperature of the body. After cooling the furnace body 1 below 40 ° C, ash is removed. To do this, the doors for cleaning 20 are opened, the door for ignition 19 and the ash drawer 21 is pulled out of the body by 20-25 cm. With improvised means, the ash is swept into the ash drawer 21 through the holes 16 and through the door 19. Through the doors 20, the ash is displaced from plates 12 to ridge grate 15, and then, as indicated in the ash box 21, the contents of which are disposed of in the established order.

As you can see from their descriptions of the design and operation of the furnace for destroying documents, the amount of additional fuel required for destruction is significantly less than in the prototype, since it is only necessary to ignite the furnace and its amount does not depend on the volume of documents being destroyed. In addition, the oven can operate in stand-alone mode, which expands its functionality. The implementation of the pyrolysis principle of fuel combustion in the furnace allows it to be burned most fully with a minimum emission of harmful substances. The design of the furnace is relatively simple and does not contain moving elements operating at high temperatures, which ensures high reliability of the design and a long service life. A consequence of the simplicity of the design is its low cost, which in turn can facilitate widespread use.

The incinerator-oven for incineration of documents has been developed at the prototype level, and its industrial development is being prepared.

Sources of information used in compiling the description.

1. Federal Law of June 24, 1998 No. 89 FZ (as revised on December 29, 2015) On production and consumption waste.

2. Patents US No. 2011052096, GB No. 1389993.

3. Patents US No. 2003021898, FR No. 2876137, FR No. 2866357.

4. Patents RU No. 2179687, 2187759, 2385343, 2476771, TW No. M370440, WO No. 2006006971, US No. 2005115442, 2005051064, GB No. 572705, FR No. 2906385, EP No. 0035980.

5. Patent RU No. 2147710 (prototype).

Claims (7)

CLAIM 1. An incinerator oven for the destruction of documents, comprising a body with a chimney, a loading door, grate plates, with an air cavity located under them and an ash box, characterized in that it additionally contains a device for distributing and feeding documents, - 4 035557 including side walls of the body and a gable tunnel with primary and secondary air ducts at the base, located with a slope between the front and rear walls of the body above the grate system, including W-shaped grates with a ridge grate and pipe grates installed vertically above the holes at the junction of the plates and the ridge grate, while the plates are installed at an angle of 40 to 45 ° relative to the horizontal plane and holes are made in them, closed by arched plates, with a total area of holes of about 15-17% of the cross-sectional area of the primary air duct, which has one side of the damper, and on the other side, connected by a section of the air duct with the underglass cavity and the secondary air duct, and the cross-sectional area of the primary air duct is approximately equal to the cross-sectional area of the chimney, the opening area into the secondary air duct is from 20 to 25% of the cross-sectional area of the primary air duct about air, while in the side and top walls of the secondary air duct, holes with a total area of 20 to 25% of the cross-sectional area of the primary air duct are made, and in the pipe grates, muffled from above, on the side surface on one side there are holes facing the plates , with a total area of 10 to 12% of the area of the primary air duct, while the area of the holes between the plates and the ridge grate is from 25 to 30% of the area of the primary air duct, and the end of the chimney is passed into the tunnel and fixed to it, while along the lateral surfaces of the tunnel above the secondary air duct have holes with a total area approximately equal to the cross-sectional area of the chimney. 2. The incinerator furnace according to claim 1, characterized in that the ratio of the areas of the holes from the secondary air duct into the tunnel and outside it is 1: 3. 3. The incinerator furnace according to claim 1, characterized in that a two-leaf or single-leaf door with a lock is installed on the entire front wall of the housing with a gap. 4. The incinerator furnace according to claim 1, characterized in that it is equipped with a casing located on the housing with a gap. 5. The incinerator-furnace according to claim 4, characterized in that the casing is placed on the casing from the top and four lateral sides, and the top cover of the casing is removable or opening. 6. The incinerator-furnace according to claim 4, characterized in that the casing is made on all sides of the casing and is equipped with air supply and exhaust pipes, and the air supply pipe is located in the lower part of the casing, and the air exhaust pipe is located in the upper part. 7. The incinerator-furnace according to claim 1, characterized in that it is equipped with a thermostat located on the body and connected by a drive with a damper.