FR2519017A1 - TANK OVEN FOR THE CONTINUOUS PRODUCTION OF COMBUSTIBLE GAS FROM ORGANIC MATTER - Google Patents

Abstract

A. OVEN WITH COMBUSTIBLE GAS PRODUCTION TANK. B. FOR THE GASING AGENT IT IS PROVIDED ON THE TOP OF CONE 19 OF THE DELIVERY DEVICE 3, A PRIMARY FEED 12 OPENING INTO THE LAYER OF BULK PRODUCT, AND A SECONDARY FEED 14, 17, WHICH CAN BE ADJUSTED INDEPENDENTLY FROM THE PRIMARY DELIVERY AND WHICH ENDS IN THE REGION OF THE DISCHARGE INTERVAL 5. C.GAZOGENE.

Description

251901 i

  Continuous production of combustion gas furnace

  from an organic material.

  The invention relates to a shaft furnace continuously producing combustible gas from an organic material,

  including organic waste, including a

  charging of the material disposed at the top of the shaft furnace, and a layer of bulk product in the tank which, under the effect of the force of gravity, is

  crossed by organic matter

  duit in bulk is supported by a

  Conical cooling tapered, rotatably mounted and disposed in the central portion of the furnace on the ash discharging device The cell furnace has a device for yielding heat for drying and subsequent degassing of the material in the upper region of the furnace. the layer of

  produced in bulk, as well as a supply of gasifier

  cation, which emerges above an incandescent bed in the lower region of the product layer.

  bulk and whose passage can be regulated by a

  controlled by the temperature of the incandescent bed.

  a width which is determined according to the

  nullometry which is established for the product of the bed

  descent, is provided at the lower edge of the

  diversion A conduit for combustible gas

  of the combustible gas produced in the shaft furnace

  is connected to the unloading device of the cen-

of the shaft furnace.

  The production of combustible gas, from wood, coal or coke, in a shaft furnace is known The combustible gas is produced by incomplete combustion of the product in the shaft furnace into which air is introduced. oxygen and / or water vapor as a gasification agent The fuel gas formed has as gaseous combustible constituents

  essentially carbon monoxide and hydro-

  gene, as well as a small proportion of methane The process of gas production is endothermic We strive to perform the training

  of gas at such high temperatures

  as possible, to obtain high proportions of

  carbon monoxide and hydrogen.

  In the case of a continual

  Apart from the shaft furnace, it is known to introduce the gasification agent into the shaft furnace; from below, and draw off the combustible gas formed at the top of the shaft furnace In this way of proceeding, the combustible gas contains considerable proportions

of tar.

  If the flow is in the opposite direction,

  therefore when the gasifier passes through the

  product in bulk in the direction of passage of the material, and the combustible gas is discharged downwards

  of the shaft furnace, the tarry and oil constituents

  those which occur during the gasification of the material, are cracked to a large extent in

  volatile compounds during the passage of distillate gas

  in the incandescent bed The cracking of

  of high molecular weight depends on the temperature

  ture The calorific value of the combustible gases that can be taken from the shaft furnace is all the more

  the temperature of the zones of the incandescent bed

  cent that the gases created must cross is higher. It has been found that the quality of the fuel gas produced in a shaft furnace decreases as the temperature gradient is greater inside the bulk product layer, between the temperature of the produced in bulk in the inner region of the tank, and the temperature of the

  produced in bulk in the area close to the wall.

  Only a part of the gas drawn from the bottom then passes through the zones having the temperature

  The remaining part of the gases is not

only imperfectly.

  The invention relates to a production tank furnace

  fuel gas from which a high quality fuel gas can be withdrawn, even if, within the gasification zone, after the addition of the gasifier, the temperature differences on the right section of the shaft furnace, differences that make more

  uniform treatment of all the gases

  in the bulk product layer.

  According to the invention, this is achieved by a shaft furnace of the type mentioned above, characterized in that for the gasification agent is provided on the top of the cone of the diverting device,

  a primary feed leading into the protective layer

  bulk feed, and a secondary feed that can be adjusted independently of the primary feed, and

  leads to the region of the spooling interval

  By subdividing the amount of gasifier

  cation to bring into a stream of primary gas introduced into the

  layer of loose product at the top of the cone of the

  process, and a secondary gas stream introduced into the bulk-product layer in the

  the turning-point, we obtain the forma-

  incandescent bed at a high temperature

  immediately before the release of the

  zer by the shift interval The current of

  secondary gas is introduced into the

  25 to 30 cm above the dewatering interval The gases withdrawn from the dewatering interval, according to the direction of transport of the

  product, must pass through the incandescent bed

  formed in order to obtain a single treatment

  form and a pronounced cracking of all substances

  these high molecular weight combustible gas.

  Tars and oily constituents are trans-

  formed by volatile compounds By producing the incandescent bed directly upstream of the outlet of the product in the chamber for the ash, homogenization of the residue exiting the cell furnace is also achieved. This facilitates the adjustment of the width of the dewatering interval by depending on the particle size of the material to be gasified, which leaves the

incandescent bed.

  To achieve a uniform distribution of

  secondary gasification agent in the incandescent bed, the secondary supply duct opens

  in a distribution channel at the foot of the

  tifling and presenting openings

  distributed around the perimeter of the foot and intended for the introduction of gasification agent into the incandescent bed. The openings are advantageously

in the form of slits.

  A variant facilitating the supply of gas for

  the gasification agent stream, for the purpose of

  formation of the distribution channel, consists in constituting the distribution channel of several conduits for gas

  extending radially below the cone of the

  of diversion In order to be able to use the

  of the combustible gas leaving for preheating of the gasifying agent, wall regions of the gas conduits are arranged in heat-conducting walls in order to have a heat exchange between the gasifying agent and the combustible gas flowing into the chamber for

the unloading of the ash.

  The invention ext explained further by

  examples of realization which are reproduced schematically

only to drawing Drawing:

  FIG. 1 represents a shaft furnace with a

  born of secondary gasification agent in the dis-

  positive taper diversion, and

  FIG. 2 represents a shaft furnace with a

  born of secondary gasification agent in the

region of the wall of the tank.

  In Figures 1 and 2 there are shown ovens

  tank to which can be brought organic matter

  to gasify, especially organic waste.

  A layer of bulk product 2 is formed within the

  of each furnace produced by the product brought to it The material moves downwards in the

  shaft furnace, under the effect of the force of gravity.

  It is preheated in the upper region.

  tank furnace, which is not shown, and

  It is dried and brought to about 200 ° C.

  In the shaft furnace, there is a rotatably mounted rotator 3 that supports the bulk product layer. The divertor device 3 is disposed in the central portion of the vessel and tapers conically to the product layer 2.

  bulk, in the opposite direction to that of crossing the

  At the bottom 4 of the dewatering device 3, there is a deflection gap 5 in the form of an annular gap between the edge of the foot 4 and the wall 6 of the shaft furnace. The degassed product falls, passing through the 5, in a chamber of an ash discharging device 7 on a bed of ash 8 and, from there, is forced, by the rotation of the pumping device, to go to a chute for the ash 10 by pallets 9 which are fixed to the lower part of the diverting device 3 and which go to the bottom of the ash bed 8 The chute for the ash opens into a box for the ash which is not shown in the drawing and which suitable for

  intermediate storage of ash.

  The ash discharging device is also connected to a suction pipe 11

  for the combustible gas formed in the shaft furnace.

  The gases formed in the bulk material layer 2 flow downwards into the shaft furnace, in the direction of passage of the material and are, after reaction, optionally supplied via

  from an intermediate tank to a combustion chamber

  The intermediate tank and the chamber of

  combustion are not shown in the drawing.

  Through the central portion of the disassembly device 3, a primary feed 12 passes through

  a primary gasifier gas stream.

  The primary gas stream is shown in the drawing by flow arrows with dashed lines. The primary feed 12 opens into the shaft furnace over a gasification zone 13 formed in the bulk product layer 2 In the gasification zone, part of the distillation gas produced in the preheating zone of the shaft furnace is burnt off with a gasification agent, and the temperature of the layer of bulk product is raised. organic waste gasifies at a temperature of between 400 and

10000 C.

  Below the gasification zone 13 opens a secondary supply 14 of a gas stream

  secondary agent of gasification agent which is

  In the embodiment shown in FIG. 1, the feed opens at the base 4 of the device.

  conical diversion 3 The secondary gas stream

  daire is introduced into the bulk product layer

  25 to 30 cm above the blanking interval

  The amount of gasification agent flowing in the secondary supply 14 can be regulated by a flow regulator 15, independently of the primary gasifier gas stream. The latter is regulated by a flow regulator 15. amount

  secondary gasification agent supplied is controlled by

  due to the temperature prevailing in the incandescent bed

  one hundred and sixteen, above the diversion interval 5.

  The amount of gasifying agent is adjusted so that the temperature of the incandescent bed is sufficient for cracking the tarry and oily constituents of the gas formed in the coating layer.

bulk product 2.

  In FIG. 2, a secondary inlet 17 with openings 7 ', guided with respect to the wall of the shaft furnace 6, opens above the incandescent bed 16

  the bulk product layer in the shaft furnace.

  This secondary supply is also connected to a flow regulator 18 which makes it possible to control the

  amount of secondary secondary gasification agent

  from the primary gas stream, depending on the temperature of the incandescent bed 16 The openings 171 open into the shaft furnace also 25 cm above the turn-off interval 5 It turned out that this distance between the supply of the secondary gasification agent and the dewatering interval, independently of the other dimensions of the shaft furnace, in particular independently of the diameter of the shaft furnace and the apex angle of the conical unloading device 3, provides a configuration of the incandescent bed corresponding to the requirements

  desired, and easy regulation of the temperature

the incandescent bed.

  During the production of combustible gas, the gas, created in the shaft furnace during drying and degassing of the material in the layer of product.

  bulk, first flows into the gasification region.

  13 This region, whose periphery is repre-

  schematically in the drawing, has a temperature gradient from the inside to the outside at the inlet of the primary gas stream of the gasifier on the apex of the cone 19 of the

  device 3, the material is warmed

  up to about 1000 ° C, while in the area of the wall of the shaft furnace

  dimension of the cross-section of the tank,

  between 600 and 7000 C Only the part of the gases formed which crosses the incandescent zone

  found in the temperature range of 900 to 1000 C -

  is cracked for the most part The remaining part of the gas is first attacked incompletely It is only in the incandescent bed 16 * -in which all the gas

  formed before going out through the interval of

  5, that the high molecular weight constituents

  of this part of the gas are cracked.

19017

  producing the secondary gas stream in the bulk product layer and the accompanying formation of the incandescent bed 16, the periphery of which is indicated schematically in the drawing in the same manner as that of the gaulification zone 13, therefore gives a high quality to the fuel gas which is withdrawn from

shaft furnace.

  In addition to a high quality of the combustible gas,

  we obtain, by the introduction of the current of gas se-

  and by the constitution of the incandescent bed 16, a homogenization of the material to be treated This facilitates the adjustment of the width of the deflection interval 5 which is determined according to the

  particle size of the product forming in the inner bed

  candescent in the lower region of the bulk product layer 2, as well as the product flow required to gasify fines for example from

  rice balls, it is good to have a breadth of

  between the edge of the foot 4 and the wall 6 of the

  approximately 3 to 20 mm in the bed

  the bulk product forms a sieve-like structure, so that only sufficiently small particles of material, which can be gasified to a large extent, are

  diverted by the disassembly interval 5.

  The maximum temperature in the incandescent bed

  cent 16 is preferably set at a temperature between 900 and 10000 C A temperature sensor 27 introduced into the bulk product layer measures

  a reference temperature in the shaft furnace,

  above the incandescent bed 16, which changes with

  The temperature sensor 20 cooperates, in the embodiment of FIG. 1, with the flow regulator 15 of the secondary supply 14 for the gasification agent. regulate in another way the flow of the agent of

  gasification in the secondary supply 14, for example

  by varying the suction pressure in the con-

  suction duct 11, or in combination with the flow regulator 15 and adjusting the vacuum in the ash discharge chamber 7.

  exceeds the desired temperature in the incandescent bed

  cent, the arrival of gasification agent is reduced, whereas in the event of a decrease in temperature,

  increases the supply of air or oxygen We can also

  The temperature of the incandescent bed 16 can be adjusted by the composition of the gasifying agent. By a metered addition of air, oxygen, water vapor or

  carbon dioxide, we can make ourselves master of the

  gasification process in a safe manner and with rapid reaction also due to the direct supply of the gasifier into the

  produced in bulk above the incandescent bed 16.

  In the embodiment shown in FIG. 2, a temperature probe 21 cooperates with the

  flow regulator 18 in the secondary supply 17.

  The control parameters indicated in the previous paragraph for regulating the temperature of the incandescent bed, namely the variation of the suction pressure or the dosage of the constituents of the gasification agent, are similarly valid for

  the embodiment according to Figure 2.

  The secondary supply 14 of the shaft furnace, followed by

  1, opens into a splitter channel

  23 formed in the foot 4 of the deflowering device

  conically and having apertures 24 in form

  slits spread around the perimeter of the foot and

  when the introduction of gasification agent into the incandescent bed 16 Instead of this arrangement,

2 5 1 9 0 1 7

the

  it is possible, for the introduction of the secondary gas stream

  in the incandescent bed 16, also provide a plurality of radially extending gas conduits 25

  in the lower part of the draining device

  3 as shown diagrammatically in the sectional view on the right in FIG.

  variant to the arrangement of the splitter channel

  in the sectional view to the left of the shaft furnace.

  The conduits 25 for the gas are constituted advantageously

  a plurality of rectangular channels of the same cross-section extending from the mouth of the secondary feed 14 to the edge of the foot 4 of the unloading device 3 In the conduits 25 for the gas,

  the secondary gas stream of the gasification agent

  passing along the bottom 26 of the measuring device

  supply 3 The bottom 26 forms a wall region

  ducts 25 for the gas which serves as a wall

  conducting heat, for effecting a heat exchange between the hot fuel gas flowing in the ash discharge chamber 7, and

  the secondary gasification agent The gasification agent

  The application is preheated in ducts 25 for

  gas countercurrent to the fuel gas, before

  trench in the bulk product layer.

  The primary gasification agent passing through the dewatering device 3 acts as a cooling agent and prevents overheating of the cone of the dewatering device. At the same time, the primary gasification agent heats up, before entering the product layer. Bulk - A cover 27, on the top of the cone 19, prevents the bulk product from entering the primary supply The device 3, the primary feed 12, and the secondary supply 14, in the example of embodiment according to FIG. 1 and, in the embodiment according to FIG. 2, the unloading device 3 with the primary feed 12, form in common a unit that can turn about an axis 28. The motor and the gears for the training of this unit are not shown in the drawing In the example of

  tion, the rotation of the unit is step-by-step.

  In a shaft furnace of the type shown schematically

  Figure 1, with a diameter of 260 mm and a tank height of 1 meter, is gasified from

  chopped straw Straw twigs have a medium

  only about 10 cm in size To the straw was added up to 10% by weight of pieces of wood The material introduced into the shaft furnace is heated

  up to about 200 C in the pre-heating zone

  lable by heat exchange with combustible gas

  product In the bulk product layer, one introduces

  The reaction zone between the top of the c 6 19 and the incandescent bed 16 has a length of about 350 mm. The highest temperature in the incandescent bed 16 is that of the air as a primary and secondary gasification agent stream. of 10,000 C. The diversion device is trained

  step-by-step with a cycle time of about 2 minutes

  10 revolutions taking place in about an hour For a flow rate of 10 kg per hour of the material to gasify,

  30 to 40 cubic meters per hour of gas can be produced

COMBUSTIBLE.

  Another shaft furnace of the type according to FIG.

  re 1 400 mm in diameter and 1.5 meters in height

  used for the gasification of sawdust which is introduced

  duit in the shaft furnace by being also mixed

  to pieces of wood The pieces of wood presented

  The reaction zone between the top of the cone 19 and the incandescent bed 16 is smaller than 150 mm in length.

  450 mm in length in this shaft furnace, the temperature

  maximum height of the incandescent bed

  10000 C The de-skimming device also performs

  step by step a full rotation 5 times per hour.

  The cycle time is approximately 4 minutes For a flow rate of 30 kg per hour of material to be gasified,

  produces about 100 m 3 / hour of combustible gas.

  On average, the fuel gas obtained in

  the shaft furnace mentioned above has the

  2% by volume of CH 4, 15% by volume of H 2, 25% by volume of Ca, 5% by volume of C 02, 53% by volume of N 2 The calorific value of

  combustible gas is between 5,000 and 6,000 kilo-

joule by m

  The gasification process may be

  in an optimal way by mastering

  the supply of primary and secondary gasification agent

  The gases that form in the bulk product layer react with the gasification agent and form,

  by introducing the secondary gas stream, directly

  above the boiling range, an incandescent bed that the distillation gases and the

  other gaseous constituents must pass through

  The parts of high molecular weight gas are thus cracked By distributing the feed

  gasification agent into a primary gas stream.

  and in a stream of secondary gas, one can master the extent of the reaction volume in

  the bulk product layer and thus the quantity of

  fuel gas produced The quantity of agent

* Maximum primary gasification to be brought is determined

  The amount of secondary gas stream is controlled according to the temperature of the incandescent bed 16 which is required for cracking.

  gaseous constituents When the need for

  is low, the supply of gasification agent

  The reaction volume in the shaft furnace is then reduced only to the bed

  directly above the interval of

  supply The adjustment range for the amount of combustible gas to be produced is between 5: 1

  about to equal fuel gas quality.

  The shape of the cone and the width of the range of the pumping device and the reaction zone are adapted to the various materials. In one and the same shaft furnace, it is preferable to

  simply changing the deflator-

  load materials of very different structures

  and with different gasification behavior to ob-

keep combustible gas.

  For the drying of the material introduced into the shaft furnace by a material charging device, which is not shown in the drawing,

  serves as a heating medium in the pre-

  heating at least a portion of the fuel gas

  heat exiting through the suction duct 11

  For this purpose, the upper furnace of the shaft furnace is advantageously double-walled. The combustible gas is sent into the intermediate space and is exchanged for counter-current heat with the waste material which descends into the layer.

  of bulk product from the shaft furnace.

  drying and degassing equipment, we obtain a

  heat, especially in the case where the fuel gas must be stored intermediately, before

  its use as a heating agent -

19017

Claims (5)

  1 Continuous production floor furnace   combustible gas from an organic material,   including organic waste, including a   tif of the material disposed at the top of the shaft furnace and a layer of bulk product in the tank which, under the effect of the force of gravity, is   crossed by organic matter and which is   naked by a shrinking device shrinking   conically to the product layer   di, mounted rotating and arranged in the central part   the tank on the device for discharging the ash, and a device for giving up heat   for drying and subsequent degassing of the material   re in the upper region of the product layer   in bulk, as well as a supply of gasification agent   which emerges above an incandescent bed in the lower region of the product layer.   bulk and whose passage can be regulated by a   controlled temperature according to the temperature of the incandescent bed, an interval of disintegration, having a width which is determined according to the particle size which is established for the product of the bed   incandescent, being provided at the lower edge of the   positive displacement and a conduit for the combustible gas discharging a produced fuel gas being connected to the unloading device of the   ash, characterized in that for the gasifying agent   on the top of the cone (19) of the   positive displacement (3), a primary feed (12) opening into the bulk product layer, and a   secondary supply (14, 17) which can be independently adjusted   from the primary supply and which leads to   the region of the deflating interval (5).   2 furnace according to claim 1,   characterized in that the secondary supply (14) leads to   in a distributing channel (23) which is arranged at the foot (4) of the conical turning device (3) and which has openings (24) distributed around the periphery of the foot and intended for the introduction of gasification agent into the incandescent bed (16).   3 furnace according to claim N 2,   characterized in that the splitter channel (23)   slots (24) in the form of slits.   4 furnace according to claim 2 or 3, characterized in that a plurality of gas ducts (25) extending radially to the lower part of the dewatering device (3) form the channel distributor (23).   Vessel furnace according to claim 4,   characterized in that wall regions (26) -   gas ducts (25) are arranged in heat-conducting walls, to obtain a heat exchange between the fuel gas flowing in the ash discharge chamber and the agent gasification.