US3215100A - Process and apparatus for desiccation, carbonization and incineration - Google Patents

Description

3,2 15,100 CARBONI ZA'I'ION Nov. 2, 1965 F. A. M. FABRY PROCESS AND APPARATUS FOR DESICCATION,

AND INCINERATION 2 Sheets-Sheet 1 Filed March 6, 1962 %w%% ATTORNEYS 3,215,100 FOR DESICCATION, CARBONIZA TION Nov. 2, 1965 F. A. M. FABRY PROCESS AND APPARATUS AND INCINERATION 2 Sheets-Sheet 2 Filed March 6, 1962 T1 Eb- BY 77% Z74 ATTORNEYS United States Patent 0 PROCESS AND APPARATUS FOR DESICtIATION,

CARBONIZATEON AND INCINERATION Firmin Alexandre Maurice Fabry, 44 Avenue Marie-Jose, Brussels, Belgium Filed Mar. 6, 1962, Ser. No. 177,860 Claims priority, application Belgium, Mar. 6, 1961, 600,985 9 Claims. (Cl. 110-8) This invention relates to a process for the desiccation, the carbonisation and the incineration of various products and an apparatus for carrying out this process, While providing a total destruction by a strong desiccation and a complete incineration of the waste products such as those from household, hospitals and industry etc., while maintaining normal sanitary conditions during the operations.

Prior refuse incinerators have various shortcomings. Combustion is not satisfactory at the beginning of the charging operation, or due to the clogging of the grid or when recharging or also when starting under cold conditions. Some liquid products or products liquified by heating fall through the grid, and clog the feeding conduits for the combustion air, and hard or incombustible bodies clog the grid. The heap charging restrains the feeding of combustion air and slows down the combustion, resulting in fumes carrying unburned products which contaminate the atmosphere. In the same manner, the blowing of combustion air results frequently in ashes and light unburned products being carried through the stack.

It is an object of this invention to avoid the drawbacks of known incinerators by a process which comprises heating the products to be destroyed to a temperature sufiicient to induce their complete desiccation and gasification. The gases derived therefrom are put in optimum condition with respect to the temperature and the admixture with combustion air, which is also preheated. The temperature will be such that it will induce the self ignition of this gaseous mixture. However, in some instances where it would be found necessary or useful, the ignition of the gases could be obtained by an associated process comprising a gas distributor, and an electric resistance, positioned in the flow circuit of the gases and combustion air. Such an instance would occur where products with a low content of fuel gases are employed. They would be drowned in a gaseous mass and seriously impair the shelf ignition and the gas-air mixture.

In a more detailed manner, the process of the invention includes rapidly heating the products to be treated to a high temperature in a container and then drying and calcining them.

The gases evolving therefrom are mixed with air preheated at a high temperature, so that the temperature of the gas-air mixture reaches the self ignition temperature of the mixture.

The ignited gases burn in a combustion chamber provided therefor. The temperature and the feed of combustion air are adjusted so as to obtain the most rapid combustion. Thus no unburned product will be found at the outlet of the apparatus. This process will also allow the destruction of waste or other products in the containers used for transporting and collecting them. These containers are constructed with a refractory metal,

so that they may be used again after the operation.

From the above, it can be understood that asepsis will be complete and all objectionable odors destroyed. Thus, the refuse-bins will neither contaminate the rooms, nor provide a source of undesirable odors. When unrecoverable containers are utilized, they will be inserted directly into the desiccation retort in which they will be burned with their contents.

Another feature comprises the possibility of working under partial vacuum, thereby preventing any back flow of fumes into the room. This is made possible by the fact that no obstacles clog the passage of the fumes and air.

The use of suction in the apparatus allows cooling of the fumes before they enter the stack, where high temperature may cause degradations, fires etc.

The suction also makes it possible to purify the room, when the atmosphere has been contaminated by the waste products.

The suction through the apparatus leaves, at the outlet of the fan, an available pressure, which allows the use of undersized stacks. This is possible since the aspirator is disposed at the outlet of the incinerator, but not at the top of the stack, as is usually the case for forced draught.

All these advantages are obtained from only one aspirator, the characteristics of which depend upon the treated products, their constituents, their proportion and the available fume conduits.

The incinerator comprises essentially a jacket or the like, in the lower part of which is provided a source of auxiliary heat, which may be a gas hearth, an electric resistance, coal, fuel, infra-red heating, battery steam or overheated air.

Immediately above this heat source, there is disposed a retort or a support for transport containers which will stand thereon and which will be disposed to allow a total combustion of the auxiliary fuel.

The products are charged through one or several doors.

A loading door and a deashing door may also be provided so that the products follow a path through the apparatus, along which they will be destroyed. In that case, there is provided a feed back of the hot gases which, before passing through the exhaust stack, will warm up the first portion of the retort which will then provide the pre-drying of the products to be treated. One or several exhaust ducts will also be provided for leading the steam of the pre-drying step towards the combustion chamber. The steam is not detrimental to the self ignition step and tends to economize auxiliary heat. This arangement will be provided in a straight line, in the form of an L, in a horseshoe arrangement or any other arrangement which seems suitable. There may also be provided slopes which facilitate the passage of the waste products through the apparatus or allow the connection of the incinerator directly to the casings of the refuse-bin tilters. When using a single retort, it will be connected directly with the loading door through the casing employed for sucking air.

When treatig refuse-bins, doors will be provided to make the introduction and removal of the bins easier. There will also be provided solid plates which will be used as pedestals for the bins. The plates must be distributed in such a way that the flow of the warming gases always contact the walls of the bins in order that the suction may always be directed evenly around the bins, even when one or several bins are not in the apparatus.

After removing the bins from the incinerator, they are cooled under a hood which will discharge the fume emanations therefrom, through the air intake. Every charged bin will be replaced by another bin ready to be used.

Under the influence of the heat, the treated products contained in the retort or the bins release steam and gases. These emanations contact a bafiie which causes them to flow in heat-exchanging relation to the air intended for their combustion. A batfie extends across the bottom of the gas combustion chamber, so that air and gases are mixed by the stirring effect provided by the bafile. The baflle comprises one or several openings disposed either centrally or on the periphery thereof or dispersed at random. The characteristics of the products to be treated and the type of apparatus will determine these particular arrangements.

When entering the combustion chamber, the gases mixed with air are heated to their self ignition temperature and then burn very rapidly. The mixture expands in the combustion chamber and is directed by a second bathe towards the walls of the chamber, so that when contacting the latter, they are cooled by the air flowing around the combustion chamber, thereby providing the desired cooling of fumes ready to be discharged and the heating of the combustion air.

The aspirator is positioned to allow it to suck the combustion air through an external casing which surrounds the body of the apparatus, the path of, cold air being provided around the stack or at the top of the incinerator. The air will be directed on the whole surface of the apparatus by a control system through which it will be fed inside the body. The regularization and the distribution of air on the largest possible surface provides the cooling of the external casing as well as the maximum heating of the air to be used as a combustion gas for the waste gases.

After passing over the entire external surface of the body, the air fed inside the body through the control openings will rise along the internal surface of the body between the latter and the auxiliary-fuel hearth. 'Ihen, between the body and the incineration bin or bins, it will be mixed with the fumes of the auxiliary fuel and heated to a maximum temperature by the time it reaches the baffle. It then enters the combustion chamber provided for the waste gases.

When using gas, fuel oil, coal or other fuels, the process provides a separate combustion chamber for the auxiliary fuel, thereby allowing a suitable air control for the best combustion and for reaching the highest possible temperature.

Nevertheless, the heating of air may be obtained independently of this device.

Between the outlet of the fumes from the apparatus and the aspirator, there is provided a draught regulator to control the suction through the incinerator and thus the proportion of combustion air for the waste gases. [In

' addition, it will also feed sufficient cold air to lower the temperature of the escaping fumes.

Any system for recovering the produced heat may, of course be substituted for this feed of cold air in any case where the heat recovery is desired and is practicable.

The deashing is provided by a container disposed either under the loading hopper or under the deashing door. The fumes are taken from the ash holder through the suction path to prevent those fumes from spreading into the room. This is obtained by a suction intake at the top of the ash bin.

The invention will be now described in detail with reference to the enclosed drawings representing schematically three embodiments of the invention.

In the drawings:

FIG. 1 is a schematic sectional view through the incinerator of the invention for incinerating products in a single container.

FIG. 3.

An auxiliary fuel may be supplied at 1 in FIG. 1. A heating device 2 may operate with any fuel, namely fuel oil, gas, coal, electricity, etc. The hearth 1 is disposed inside a casing 3 With two walls 4and 5 which form a jacket 6 for combustion air which is circulated therethrough. Above the hearth L'there is disposed a container 7 containing the products to be incinerated, which are introduced through a loading door 8. This container is fixed inside the incinerator by any suitable means (not shown). Above the container 7, at a small distance therefrom, a bafile 9 defines the lower portion of a chamber 10 for the combustion and for the cooling of the fumes. -In addition, this chamber '10 is limited by the wall 5 of the casing.

At the top of chamber 10, there is provided a discharge stack \11 containing a fume extractor v12 and provided additionally with a draught regulator 13. Before the inner mouth of the stack 1 1, there is provided a baflle plate 14.

On its upper face, the external wall 4 of the casing 3 has air ports 15 through which air passes into the incinerator jacket 6. At its lower end, the inner wall 5 of this jacket has control openings 16 through which air may pass to the inside of the apparatus around the hearth 1.

The incinerator operates as follows: The waste prodducts are introduced into the container 7 through the door 8. The combustion in the hearth .1 raises the temperature of the waste product-s. The fumes of hearth 1 flow around the container 7. The heated waste products are freed from steam, emit gases and burn. The fume extractor 112 produces a partial vacuum inside the apparatus, by sucking fluid from the hearth 1 and from the ports 15 through the air jacket 6 around the hearth 1, around the bin 7, and through the bafiies 9 and 14 of the combustion chamber 10. External air and fumes coming from the hearth 1 mix as they flow around the desiccation container 7. The gases coming from the hearth -1, the external air fed through the air ports 15 and thence through the air jacket 6 and the control openings 16, together with the desiccation gases from container 7 are mixed under the influence of the bafile device 9. Since desiccation container 7 is closed, except at its upper portion, the suction can only pull the air around this container and air does not flow into container 7. The desiccation gases therefore do not absorb oxygen which would burn them inside the container. The loading door '8 is provided with tight gaskets. The absence of draught within container 7 will also prevent any discharge of solids.

On the contrary, at the level of the baffle device, there is obtained a mixture of oxygen containing air and fuel gases both heated at a high temperature which provides suitable conditions for a complete and rapid combustion in the combustion chamber 10, the resultant fumes being discharged through the stack 1 1.

The flow of air sucked through the suction ports 15 and through the jacket 6 provides heat insulation for the assembly.

The system for extracting the fumes from chamber 10 prevents any pressurizing inside the incinerator. It avoids any danger of odors discharging into the room. The power of the fume extractor 12 will be such that it will allow, through the draught regulator 13, a feed of cold air, which will lower the temperature of the fumes in the stack.

The proportion of sucked air will be controlled automatically by the draught regulator according to the intensity of the fume emanations.

As can be seen more clearly from FIGURE 1 an ash bin 17 is disposed beneath a de-ashing door 18 for receiving the residue from within container 7. When the deashing door 18 is opened, the residue may be raked into the ash bin 17 through said de-ashing door. In addition, means (not shown) are included in the de-ashing door for providing openings through which the odors from the residue in the ash bin 17 may be sucked therefrom without carrying along the residue inside of the ash bin.

In the modified embodiment represented schematically in FIG. 2, there are provide locations for several containers '19 above the hearth 1. The containers 19 are supported in a suitable manner (not shown) by pedestals 20. For the remainder, the operation is the same as the one described hereabove.

In the embodiment of FIGS. 1 and 2, as described above, the operation is discontinuous; that is, the waste products to be incinerated must be inserted into the container, incinerated, and the residue moved before a second batch of Waste material may be inserted therein.

However, in the embodiment as shown in FIGS. 3, 3a and 3b, and described more fully herein below, the operation is continuous. The waste products are fed through a loading door 8 and they slide down into an L-shaped incinerating container 7. The other end of the container serves as the exit for the residue. Thus, a separate entrance and exit are provided in the embodiment of FIGS. 3, 3a and 3b, which obviates interruptions in the incinerating process during the loading and unloading operations.

In the aforementioned embodiment of FIGS. 3, 3a and 3b, there are provided a loading door 8 and a separate deashing device 18', the latter being completed by an admission door 21.

This modification derives from the internal arrangement, in which the desiccation container 7 is L-shaped. The products charged through the door 8' decrease in volume progressively as they are moved towards a de-ashing device 18' and cover 21, while being completely incinerated. In the first part of their travel in portion 22, they are pre-dr-ied by a draught return device 23 surrounding the portion 22. A discharge circuit 24 for the steam produced during the pre-drying connects the portion 22 to a combustion chamber 10'. A fume extractor 12' is disposed after the draught return outlet 23. For the remainder, the operation is the same as described heretofore.

Turning now to the operation of the incinerator shown in FIGS. 3, 3a and 3b, the fume extractor .12 sucks air and gases along a path to be described below. The air and gases which are sucked in by the fume extractor are mixed with relatively cool outside air through a draft regulator 13' to thereby cool the fumes before they are forced out in a direction, as shown in FIGS. 3:: and 3, through a chmney shown on the top of FIG. 3 in a manner similar to the cooling operation of the embodiments shown in FIGS. 1 and 2.

The beginning of the path through which air and gas is sucked by the fume extractor 12' is shown in FIGS. 3 and 3a as suction port 15'. The air is sucked through a jacket 6', formed by an external wall 4' and an internal wall 5', and thence around the hearth '1 to be heated thereby in a manner similar to that described in the embodiment .of FIGS. 1 and 2. Simultaneously, the hot air is sucked from the hearth and mixed with the air which has been pulled through control openings 16. The mixture is then circulated around one leg of container 7', as shown in FIG. 3b, to thereby heat the waste products which are piled in that portion of the container. The gases which emanate from the portion of container 7' shown in FIG. 3b are sucked upwardly and mixed with the heated air as the gases and air pass through a bafiie 9'.

The combined gases and air pass into combustion chamber .10 where they are ignited in a manner similar to that described in the operation of the embodiment of FIGS. 1 and 2. The remains of the burned fumes in chamber 10' are then sucked, as indicated by the appropriate arrows, to the draught return device 23 and around the inclined portion 22 of container 7' and thence into the fume extractor 12'.

It will be noted that the hot fumes which are circulated around the portion 22 provide a means for predrying the waste products which have been inserted therein. Thus,

the preheating of section 22 allows the removal of an important portion of the humidity of the waste products therein. The gases from that portion escape through the discharge circuit 24 where they are mixed and combusted in chamber 10'.

Thus, it can be understood that the operation is initiated by feeding waste products through door 8' into portion 22 of container 7 where said products are predried before they are pushed further into the container by the insertion thereafter of additional waste products. The insertion of additional batches push the first predried batch around the corner formed by the Lshaped container 7' where it is distilied, carbonized, calcina-ted, etc., by the heat produced by the burner disposed beneath the container, as described above.

Further batches push the residue of the first batch forward to the end of the L-shaped container 7. The residue is then raked through deashing door 18', as in the prior embodiment, into ash bin .17 by opening cover 2 1 and inserting the rake theret'hrough. However, door .18 may be left open and the ashes will be forced automatical- 'ly into the ash bin through the door by the pressure of the preceding batches, caused by said pushing resulting by the insertion of said additional batches, which push the residue forward, as described above. When the ash bin 17 has been loaded door 18' is closed and the ash bin may be taken away and emptied. Afterwards it is returned and placed under door 18 to be once again in position for receiving the residue from container 7'.

While various embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles, it S'hOlllld be understood that the invention may be embodied otherwise without departing from such principles.

I have described what I believe to be the best embodiments of my invention. 1 do not wish, however, to be confined to the embodiments shown. what I desire to cover by Letters Patent is set forth in the following claims.

What I claim is:

'1. An incinerator, comprising an enclosure, means for producing heated fluid positioned within said enclosure, means for holding solid and liquid waste products, said Waste holding means including an opening in the top thereof and a liquid tight bottom portion, a source of oxygen, a passageway within said enclosure having one end connected to said source of oxygen, a portion of said passageway partially encompassing said heat producing means and said waste holding means, a combustion chamlber positioned above said means for holding waste products and including means wherein the oxygen, heated fluid and fumes which emanate from the waste products are combined, self-ignited, and burned, said chamber including a plurality of openings, a duct connected to said chamber, means for sucking the oxygen and heated fluid and gases which emanate from said waste products through said passageway, and the remainder of the burned combination into said duct, and means for cooling the contents of said duct.

2. An incinerator as in claim 1, wherein said waste holding means products include an airtight charging door.

3. An incinerator as in claim 1, wherein said waste holding means material includes at least one reusable open top container.

4. An incinerator as in claim 1, including means for collecting ashes from said waste holding means.

5. An incinerator as in claim 1, including battle means positioned between the Waste holding means and the combustion chamber for combining the oxygen heated fluid and fumes from the waste products.

*6. An incinerator as in claim 1, wherein said waste holding means includes an L-shaped container having a predrying section in one leg of the L.

7. An incinerator, comprising an outer insulating Wall, an inner wall enclosed by said outer wall, a first passageway formed between the walls, said passageway having an opening at one end, a supply of fluid containing oxygen connected to said passageway opening, an open topped hearth positioned within the incinerator, means for supplying heat to said hearth, a container positioned above said hearth, said container having a closed bottom, an opening in the top thereof and an airtight charging door at one end, a second passageway for-med between the inner wall and the container and hearth, a chamber positioned above said container, said chamber having an opening in the bottom and top thereof, a stack, said stack being connected to the opening in the top of the chamber, a draught regulator inserted within said stack, means for exhausting fluids from within the incinerator positioned within said stack, whereby said exhausting means sucks fluid containing oxygen through said first and second passageways, heated fluid from said hearth and fumes from said container, up into said chamber and including means wherein they are self-ignited and burned, and said exhaust-ing means sucks the burned remainder into said stack, along with cooling fluid from said draught regulator.

8. A process for the desiccation calcinat-ion and incineration of waste material comprising the steps of generating hot gases in a heated chamber, passing the hot gases into heat exchange relation with an apertured container and heating the waste material in the container to produce fumes having a temperature at least as high as their self-ignition temperature mixing relatively cool air with said hot gases, exhausting fumes from the container, combining the fumes with the mixture of the hot gases and relatively cool air, allowing the combination to selfignite and burn, and exhausting the remains of the burned combination of fumes, gases and air.

9. A process as in claim 8, including the step of mixing a cooling air with the remains of the burned combination of fumes, gases and air.

References Cited by the Examiner UNITED STATES PATENTS 1,137,424 4/ 15 Ricketts 110-8 1,299,975 4/19 McCutcheon 1-109 1,769,879 7/60 Ho'wle 1 1018 1,906,023 4/ 3-3' Tobin 1 10-1 1 2,396,091 2/46 Barnes 110-18 X 2,811,937 1 1/57 Bouchard 1 108 2,988,023 6/ 61 Osswald 1 10-8 3,043,248 7/62 Martin 1108 FREDERICK L. MATTESON, JR., Primary Examiner.

PERCY L. PATRICK, JAMES W. WESTHAVER,

Examiners.

Claims (1)

1. AN INCINERATOR, COMPRISING AN ENCLOSURE, MEANS FOR PRODUCING HEATED FLUID POSITIONED WITHIN SAID ENCLOSURE, MEANS FOR HOLDING SOLID AND LIQUID WASTE PRODUCTS, SAID WASTE HOLDING MEANS INCLUDING AN OPENING IN THE TOP THEREOF AND A LIQUID TIGHT BOTTOM PORTION, A SOURCE OF OXYGEN, A PASSAGEWAY WITHIN SAID ENCLOSURE HAVING ONE END CONNECTED TO SAID SOURCE OF OXYGEN, A PORTION OF SAID PASSAGEWAY PARTIALLY ENCOMPASSING SAID HEAT PRODUCING MEANS AND SAID WASTE HOLDING MEANS, A COMBUSTION CHAMBER POSITIONED ABOVE SAID MEANS FOR HOLDING WASTE PRODUCTS AND INCLUDING MEANS WHEREIN THE OXYGEN, HEATED FLUID AND FUMES WHICH EMANATE FROM THE WASTE PRODUCTS ARE COMBINED, SELF-IGNITED, AND BURNED, SAID CHAMBER INCLUDING A PLURALITY OF OPENINGS, A DUCT CONNECTED TO SAID CHAMBER, MEANS FOR SUCKING THE OXYGEN AND HEATED FLUID AND GASES WHICH EMANATE FROM SAID WASTE PRODUCTS THROUGH SAID PASSAGEWAY, AND THE REMAINDER OF THE BURNED COMBINATION INTO SAID DUCT, AND MEANS FOR COOLING THE CONTENTS OF SAID DUCT.

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