DE10256674A1 - Combined dehumidification, drying and particle size control of solids - Google Patents

Abstract

In order to achieve larger granules with low residual moisture in the drying of sticky thick materials that are difficult to dewater with little expenditure on equipment and energy, it is proposed to integrate a centrifuge in a dryer housing in a combined dewatering and drying device so that at least the solids discharge area of the centrifuge is located directly in the The dryer housing is located and the moist particles of the spun off solid spray from the centrifuge hit the dry particles of the surrounding circulating fluidized bed in a good spatial distribution after multiple deflections. The dwell time in the spray zone of the particles, which increase in size due to build-up granulation and at the same time dry, can be adjusted by the speed of the hot gas. The flow of the hot gas is specifically influenced by guide and impact elements installed in the dryer room in order to achieve an even distribution of solids and gas, to avoid dead spaces and to ensure intensive contact of the hot gas with the moist, constantly increasing solid particles. According to the invention, the moist thick matter particles which have been mechanically pre-dewatered and then finely dispersed in the centrifuge are continuously distributed evenly in the drying gas containing solids and thus prevented from premature contact with the dryer walls, the fine dry particles are enlarged by granulation build-up ...

Description

The invention relates to a method and a device for producing a dried, granular or powdery goods from a suspension or slurry, e.g. B. industrial sludges such as gypsum, fine coal, mineral sludge, organic fermenter broth, paint sludge, sewage sludge or the like, in which the continuously added suspension first in a continuously operating centrifuge such as B. solid bowl centrifuge or Sieve screw centrifuge is mechanically dewatered at the same time steadily drained Thick matter immediately and without intermediate storage and dosing and without leaving the apparatus at least one further treatment such as B. a short-term drying and / or granulation of only a few seconds, then pneumatically transported to the separator and continuously discharged there. Furthermore, the invention relates to a device for performing a such a short-term procedure with a solid jacket screw joint or screen screw centrifuge for mechanical drainage inside, one that at least partially envelops the centrifuge Dryer housing, the rotating solid discharge of the centrifuge at the same time as a dosing device and atomizing machine for the voreniwässerten Solid in the enveloping Dryer acts with means for deflecting the particle trajectory Axis direction of the centrifuge, with at least one hot gas inlet and at least one outlet for the dried Solid particles and the drying gas, a pneumatic delivery line, an after-drying, a separator with discharge device for the dried Well, a blower for promotion the gases, a gas heater, a gas cleaning station and one Exhaust outlet.

A method and an apparatus of this type are known from the EP 0.591 299 as well as from the DE 196 31 605.7-09 and the DE 44 07 536 A1 known.

In this known dehumidifier are those emerging from the centrifuge at high speed Thick matter particles by suitable means, e.g. B. by baffles or by suitable gas flow deflected in the axial direction of the centrifuge.

The hosed pre-dewatered Solid particles are removed from the drying gas at a high relative speed bathes and dried very quickly. The drying room is for example a stepped concentric annulus. It is made from the outer dryer housing, the internal rotating drum shell of the centrifuge or a not surrounding the rotating drum of the centrifuge rotating housing as well as the two housing end walls.

In the DE PS 12 17 983 describes a method and the device for this purpose for the heat treatment of a granular or powdery material, in which the already granular, moist material is introduced in a hot air stream, dried in a fluidized bed, crushed in the fluidized bed or in a beater mill, sifted and the dried fine material is discharged , the coarser particles advantageously staying longer in the system. In the DE PS 39 15 082 describes a method and a system for dewatering and drying sewage sludge, which consists of many individual devices connected in series with different assigned functions.

The DE OS 26 28 948 describes a process for dehydrating and drying fine-grained products from a suspension consisting of a mechanical filter and a rotating contact dryer.

In the DE OS 33 40 636 A method with a device for discontinuously operated combined dewatering and drying is shown in several devices connected in series, but the product has to be treated in a long-term dryer and can change adversely.

There are also a number of proposals for combined dehumidification and drying, such as in the DE PS 36 30 920 or DE PS 948 497 where a dryer is connected directly after a pusher centrifuge.

In the OS DE 1 432 864 a device for the production of dry solids from solid-liquid mixtures is known, which after mechanical dewatering the moist solid, for. B. sodium bisulfite, crushed with a rotating splitter before the downstream, operated with hot nitrogen current dryer.

In US PS 1 936 866 a Combination of a screen centrifuge with a centrifugal dryer for Dehumidify and chemical changes described by ammonium sulfate crystals.

In the DE OS 24 55 312 A solid-bowl screw centrifuge with a downstream device for dewatering and washing calcium sulfate hemihydrate, which is produced as a waste product with harmful impurities built into the gypsum and therefore cannot be processed in conventional drying processes without a reduction in quality, is described. In order to remove the impurities contained in waste gypsum, the gypsum is recrystallized in calcium sulfate-alfa hemihydrate immediately after leaving the decanter.

In the listed methods and devices can either just very coarse-grained Solids in the listed Screen centrifuges are centrifuged and then dried, or the number of for the intended treatment of the necessary individual apparatus and conveyors is very large.

Solid-bowl screw centrifuges are used to separate the liquid from fine-grained industrial products with a large specific surface area successfully used. The separated solid cake, however, binds relatively large amounts of liquid from the mother liquor, which can only be removed with great effort in downstream washing and drying devices in order to obtain the solid in pure form. The separated fine-grained solid contains a high residual moisture and usually has a sticky, pasty consistency, which often leads to blockages in the downstream transport equipment and apparatus.

Because of the long stay during the subsequent treatment such. B. Drying becomes certain substances damaged by chemical side reactions, or the yield of desired Ingredients is due to progressive disintegration during the long processing time less, such. B. in drug production from biotechnological fermenter broths. With particularly high quality Products such as B. certain chemical products or pharmaceuticals, is the danger due to the large number of apparatuses and conveyors used contamination and product contamination very large. For these extremely sensitive products is the processing from start to finish in a closed combined multifunctional device with very short treatment times and very small, at the same time product quantities in the apparatus very much in the continuous process advantageous.

This, for sensitive, industrial manufactured fine-grained Suspension requirements, such as the shortest treatment time, are lower hold up on solids, high active substance yield rate, no contamination, Encapsulation against the environment, multiple functions in one, continuously working apparatus, low investment costs, become present from the state of the art inadequate and unsatisfactory Fulfills.

When dehumidifying sludge-like solid liquid mixtures through mechanical dewatering in the centrifuge to a moist thick material and then drying in the outer drying room to granulate, must Minimum degree of mechanical pre-dewatering in the centrifuge reached so that it does not become undesirable with certain sludges Gehäuseverkrustungen comes. As has been shown in practice, are in particular at very poor mechanical pre-dewatering by the centrifuges or with very sticky and moist thick matter deposits and Incrustations on the deflection surfaces, in the dryer housing or possible in the following devices. This creates disorders and business interruptions in continuous drying operations, associated with great economic disadvantages. So far you have tried such difficult to be drained sludges z. B. by adding additives in their moisture and adhesive behavior cheap to change. The cost of this is however considerable.

Another disadvantage is with fine-grained suspensions the small size of the dried particles and their grain distribution. That, through the process of particle formation small particles generated at the solid discharge of the centrifuge very big specific surface, allow very short drying times, but are used for storage and processing the dried product sometimes larger granules required. Especially in the case of very low residual moisture, fine-grained dried ones tend sludges for dust generation during loading or transport.

The invention is therefore the object based on avoiding these disadvantages and a combined dehumidifier the one mentioned at the beginning Way to create, even with poorly dewatered Thick matter, or even with very sticky sludge no deposits and incrustations can occur in the dryer room Effort and the cost of the entire treatment, such as mechanical dehumidification, washing, chemical Transformation, expulsion more volatile Components, drying, avoiding undesirable side reactions, germ-free, Increase the yield, through the short-term treatment in a continuous working multifunction apparatus and significantly reduce the Size of the dried solid particles while the drying process can be controlled.

This object is achieved according to the invention with the measures of the characterizing part of claims 1, 43, 2 to 70, solved.

Advantageous embodiments of the Invention are in the subclaims specified.

The invention provides for the fine Dispersion of the pre-dewatered Thick matter in the spray zone the centrifuge with a high concentration of already dried To enforce particles evenly and these dispersed thick matter particles well in the drying gas to distribute. The mass of the sprayed damp small particles in the dryer room should evenly the surface of the in and around the spray zone around drier particles are applied. The Dwell time in the spray zone of the particles that enlarge and dry at the same time due to build-up granulation is adjustable by the speed of the hot gas. The relative speed of the hot Opposite gas the constantly superficial moistened particles should be as large as possible to ensure a very fast Dry the moist, enlarging solid particles in the fluidized bed and during of the subsequent pneumatic transport.

In a variant of the combined dehumidifying device according to the invention, the active chamber walls in the dryer are designed, for example, outside the rotating centrifuge drum in such a way that a dense fluidized bed is formed around the spray zone and none are thrown out th wet particles directly on the drying edges. The fine, moist and sticky particles dispersed by the centrifuge should accumulate on the surface of the constantly moving particles present in the fluidized bed and enlarge them. The flow of the hot gas is specifically influenced by guide and guide plates installed in the drying room in order to achieve an even distribution of solids and gas, to avoid dead spaces and to ensure intensive contact of the hot gas with the moist, constantly increasing solid particles.

Perforated walls with gas flow are also suitable for wall incrustations in the combined dehumidifier to prevent by sticky moist thick particles if by the incoming hot gas the sticky particles are kept away from the walls until the Particles on their surface enough are dried and then their lower moisture content adhesion tendency to lose. Especially with organic sludges with a pronounced glue phase is the tendency to adhesion particularly large in certain moisture ranges and can according to the invention in this Drying device in the fluidized bed overcome by granulation become.

The drying room can be divided in zones with different gas velocities, around the particle concentration and the particle sizes in the to influence individual areas of the drying room in a targeted manner.

The one for fluid bed production required gas distribution and speed can be determined by the Inflow area different be designed.

By blowing in already dried smaller ones Solid particles in the spray zone the centrifuge can be the average grain size and the grain distribution control the dry product. The one from the centrifuge continuously generated, radially outward directed spray of pre-dewatered fine solid particles meet the multitude of surfaces of the injected solid particles in the surrounding fluidized bed. The grain shape can also be so targeted influence. Smaller dry matter particles from the selected fluidized bed or from sieved fractions of the dry product, can for pelletizing in the vicinity the spray zone returned or with the hot gas introduced become.

The larger particles formed by build-up granulation possess a higher Swarm sink rate and sink within the fluidized bed downwards or prefer to stay in zones with higher gas Upward speed up. The larger particles that have sunk into the lower region can be preferred through funding agencies transported out of the dryer room in the gas distribution floor become.

Due to the geometric design the zone in the spray area the centrifuge can ensure that there is primarily stop smaller particles with a lower swarm sink rate can, whose diameter will be enlarged should.

The temperature distribution in The individual fluidized bed areas can be introduced by hot gases Heating the wall surfaces or controlled by heating pipes in the fluidized bed.

Due to the granulation in the Solid spray zone a centrifuge, preferably a solid bowl centrifuge or a centrifuge with a sieve, in the surrounding fluidized bed and the measures described let yourself specifically produce a dry product with large granules without to the advantageous combined drainage and drying in one only machine with very high heat transfer rates and large volume-related To have to do without evaporation rates.

In another variant of the combined according to the invention Dehumidifiers are for example on the outside of the rotating centrifuge drum elements protruding into the dryer room, which the gas flow kindle and for a strong counter current and nearby turbulence the spray zone of the centrifuge solids discharge.

The high ejection speed the one from the dewatering centrifuge hosed fine solid particles to reduce and their Can limit trajectory in the spray zone fixed or moving baffles with rigid or elastic active surfaces be installed, which completely or only partially the centrifuge discharge zone surrounded to the hot gas flow not to hinder.

When rotating with the centrifuge single or annular baffles multiple deflection bowls or cones are recommended as the braking effect on the solid particles is not as strong as with non-rotating ones Baffles. A multiple deflection also distributes the sprayed solid better in the circumferential direction and in the width in the gas flow. Also through a multiple opposite few wise displacement of the solid waste openings in the axial direction achieved a better distribution in the gas flow.

The baffles built into the spray zone can also the sprayed out fully or partially wet fine fine solid particles into others through which gas flows Zones still direct around even smaller solid particles continue to build or better distribute the solids in the gas stream. Also drum parts of the dewatering centrifuge covered by the gas flow, as required for full-screen centrifuges, for example targeted particle deflection with solid spray and supplied with a Hot gas flow interspersed become.

Immediately before, in and over the Spray zone of the Allow extended drying rooms downstream of the centrifuge a selective post-drying of the larger solid particles the formation of a circulating fluidized bed.

Downstream, into the pneumatic delivery line integrated convective flight dryer in front of the separator or long-term transport dryer after the separator, the Further increase the degree of drying of the solid granules. The Residence time of the solid and the relative speed to the drying hot gas can through impact surfaces and deflection surfaces increase in the after-dryer due to the braking effects.

The achievable with the invention Advantages are in particular that instead of a variety of devices and apparatus for the treatment of fine-grained, industrially manufactured suspensions and products a single, compact multifunctional device in continuous operation and with a high throughput capacity that is multiple, simultaneously can carry out ongoing work steps in one apparatus, controls the granule size, the product quality increases, incrustation prevents and reduces the investment and operating costs.

Due to the high heat transfer rates a number of advantages, such as low energy consumption, small compact design, small pipe diameters and apparatus, as well as low Investment and operating costs.

By arranging the dryer room around and above the spray zone of the pre-dewatered solid that can possible Dryer volume relatively large despite the small centrifuge be because the dryer case according to the invention regardless of the total length the inner dewatering centrifuge is. The evaporation capacity is the high product throughput of the Centrifuge adjusted.

Due to the cross flow of the Solids discharge from the centrifuge can increase performance and Size of the dryer also independently on the size of the dewatering centrifuge be adapted to requirements.

With less mechanical pre-dehumidification through the centrifuge is an even greater water evaporation capacity required. The required drying gas quantities for example 5 t / h water evaporation capacity per machine require very large flow cross sections. The centrifuge with its solid spray zone is now only Product entry device and atomizer machine for the pre-dewatered Thick fabric.

The total evaporation capacity According to the invention, the drying system is no longer used by the combination machine provided alone. The downstream post-dryer and the pneumatic one too Transport by hot gas some of the drying capacity of the system is provided in the lines.

It is important for the overall function that the pre-dewatered product is converted into a pneumatically transportable degree of dryness by the multifunction machine.

In addition to these advantages of the invention are the prevention of incrustations and caking even with difficult to be drained whitewash to mention. As a result, the area of application and application of the combined drainage and drying machine also extended to products manufactured after the mechanical drainage Result in thick matter that is very sticky or very high Moisture content and great problems in other dryers prepare. Business interruptions caused by caking due to too moist mechanical pre-dewatering in the centrifuge and the associated costs are avoided.

The achievable with the invention Advantages are in particular that the multifunction machine the difficult drying sections of the glue phase i.a. without backmixing overcomes additional substances.

The after-drying is thereby in greatly relieves moisture evaporation.

Another advantage is that already existing sludge centrifuges for the drainage only in the usual Construction of solid jacket centrifuges or screen screw centrifuges in the manner according to the invention can be retrofitted to multifunction machines, in which mechanical drainage, Drying and granulation can be carried out.

The invention uses for the first time advantageous dispersing properties of continuously charged and spraying centrifuges, (including solid bowl screw centrifuges, Solid bowl nozzle centrifuge, Sieve screw centrifuges or nozzle separators be understood) as an atomizer machine, so that according to the invention one Slurry centrifuge instead of the previous, only separation function Now two main functions can be assigned: First, the mechanical Separation of thick matter from the suspension, and the other Dispersion and atomization of the separated thick matter into the smallest particles and their distribution and drying by a stream of drying gas. This second function, namely the advantageous use of the fine dispersing properties of the thick matter waste a slurry centrifuge in the design z. B. a solid bowl centrifuge so far for the purpose of spray drying technically not used.

More details, advantages and Features of the invention are with the exemplary embodiments based on Drawings closer explained.

Show it:

- 1 the longitudinal section of a combined Centrifuge dryer with a solid bowl screw centrifuge as an atomizing machine, with a solid fluidized bed around the entire centrifuge drum.

- 2 the combined centrifuge dryer from 1 in cross section

- 3 a combined centrifuge dryer with all additional system parts and peripheral devices.

- 4 a combination of a solid bowl screw centrifuge with a flow dryer with solid enrichment only around the spray zone of the decanter.

- 5 a combined centrifuge dryer with a vertically arranged decanter as a spraying machine in the fluidized bed with an overflow weir for the solid.

- 6 a cross section of a combined centrifuge dryer as a combination of the solid discharge of a solid bowl centrifuge with a circulating fluidized bed dryer without perforated plate bottom and with solid deflection devices.

- 7 a system diagram for self-inerting cycle gas operation with a centrifuge dryer and pretreatment of the suspension by external dry material backmixing.

- 8th a combined centrifuge dryer with a rotating fluidized bed and internal solids return

- 9 the cross section too 8th

- 10 a schematic longitudinal section of a combined centrifuge dryer as a combination of the solid discharge of a screen screw centrifuge with two different filtrate outlets and a combination of different impact cones.

- 11 a longitudinal detail view for thermal expansion appropriate storage of the combined centrifuge dryer on the centrifuge frame and for sealing the dryer housing against the rotating centrifuge components.

- 12 a longitudinal section through the spray zone of the combined centrifuge dryer as a multifunction machine with a dispersing aid through a fan wheel with pin mill and ventilated baffle cone.

- 13 a view of the completed system of a combined centrifuge dryer with a circulating fluidized bed dryer, with a second after-dryer before and a granulating device for the product after the cyclone separator.

The in 1 in longitudinal section and in 2 Combined centrifuge dryer shown in cross section is a dewatering and drying machine and has a solid bowl screw centrifuge 1 known type. In addition to mechanical dewatering, the solid-bowl screw centrifuge also serves as an atomizing machine for the pre-dewatered solid and has a fluidized bed of solid material around the entire centrifuge drum 1 surround. The outside is cleaned automatically by centrifugal force. Instead of the solid bowl screw centrifuge shown 1 can also use other centrifuges suitable for dewatering, for example sieve jacket centrifuges, solid jacket nozzle centrifuges, 3 - Phase separators or separators are used in which the separated solid phase is then to be dried. The solid-bowl screw centrifuge referred to below as an example of a dewatering centrifuge 1 has a rotating drum jacket 2 on which at its axial ends on roller bearings 3 is rotatably mounted. The drum jacket 2 tapers conically at one of the two ends and has tapered openings at its tapered end 4 provided which the drop zone 5 for the pre-dewatered thick matter 6 forms. Through a mud pipe 7 inside the centrifuge 1 supplied liquid sludge 8th is in the centrifuge 1 due to the centrifugal force in a thick material 6 and a clarified liquid 9 separated that at the other end of the drum shell 2 from the centrifuge 1 in a separate housing, the central chute 10 , is hosed.

The the centrifuge 1 Directly surrounding dryer is through an outer dryer housing 11 and one, the rotating drum 2 surrounding inner housing, not shown 12 or through the drum 2 itself, as well as through the two end walls 13 and 14 educated. The drying gas 15 is through hot gas pipes 16 from below under the fluidized bed 17 initiated. The fluidized bed 17 consists of a perforated sheet with round or slit-like holes emitted by the hot gas 18 be flowed through. The pressure drop occurring when flowing through should be so great that the hot gas 18 lengthways and crosswise evenly into the dryer room 19 entry. The free hole area ratio of the fluidized bed 17 is normally chosen so that there is a pressure drop which corresponds approximately to the pressure loss of the fluidized bed itself. The evenly entering hot gas 18 flows around and penetrates the entire circumference through the decanter solids discharge openings 4 thick matter dispersed in the form of fine particles 6 , A bubbling gas-solid fluidized bed forms in the entire drying room 19 from which the rotating solid bowl centrifuge 1 fully overflowing from the outside and enclosing itself. So that the radially emerging solid spray 6 consisting of pre-dewatered moist particles, not the dryer wall 13 wetted and also to pre-dry the sticky particles is on the rotating drum jacket 2 next to the drop zone 5 an impeller 20 attached, which hot gas in the direction of the solid spray 6 blows and deflects it in the axial direction. The solid spray mist dispersed into the fluidized bed 6 settles on the already dried Particles of the fluidized bed in motion on the outside and enlarges these particles. The hot gas 18 dries the externally moistened particles very quickly because of the large specific surface area of the solid particles 6 is available for heat and mass transfer. The gas emerging at the top of the bubbling fluidized bed, cooled by the drying 21 , is in the upper area of the dryer housing 11 collected and on the suction pipe 22 aspirated. The lighter, smaller particles and the dust with the gas 21 discharged. The larger particles formed by build-up granulation 23 sink downward within the fluidized bed to the fluidized bed bottom 17 and are from the screw conveyor 24 carried out constantly. That at 16 Hot gas introduced from below 15 is due to the inclined fluidized bed floors 17 distributed according to their free hole cross-section and flows with different gas velocities 18 in the drying room 19 on. Falling larger particles get through the inclined position of the perforated fluidized bed floors 17 automatically into the transport screw, which is not or only slightly flowed by the gas 24 and are carried out. The upward speed 47 The gas in the fluidized bed can be caused by the angle of inclination and the perforation of the two fluidized bed floors 17 be designed in such a way that large, dried, large particles grown into the screw conveyor only by build-up granulation 24 reach.

Due to the inclination of the fluidized bed 17 to the screw conveyor 24 All sunken larger particles are conveyed towards the center and discharged. The size of the sinking particles 23 can about the speed of the gas 18 to be controlled. The denser the solids concentration in the drying room 19 becomes, the more dried particles become due to the lower swarm sink rate with the exhaust gas 21 discharged. By designing the dryer housing 11 , the free area ratio of the fluidized bed 17 , the speed of the screw 24 and the amount of hot gas 15 the separation cut of the grains can be determined, the above at 22 or below at 24 be carried out. The dryer housing 11 can be extended upwards in a manner not shown instead of the vertical walls. In the front wall 14 can also be a side opening with adjustable overflow weir as an additional solids outlet. It can be around the drop zone 5 standing, moving or rotating impact surfaces or deflection surfaces 25 be installed.

In 3 a combined centrifuge dryer is shown with other system components and peripheral devices as an example. Of course, other apparatuses, paths, circuits, links can also be arranged around the combined centrifuge fluidized bed dryer, for example for one-time gas continuous operation or recycle gas operation. The centrifuge dryer consists of the centrifuge rotor, which is partly built into the dryer 1 with an outlet 10 for the mechanically separated centrate liquid 9 and a solid discharge zone 5 on the other end. The dryer housing 11 is divided into four sections in the axial direction. The first paragraph 26 near the solid spray zone 5 is used to introduce dried solid particles mixed with carrier gas, which are caused by the moist solid spray 6 the centrifuge 1 are constantly wetted externally. The introduced dry matter grains ensure that the spray mist 6 is constantly surrounded by absorbable, dry, particles of the fluidized bed. The damp spray mist enveloped by particles 6 can not be sprayed directly onto the dryer walls, it is shielded by the fluidized bed. The second section 27 of the dryer housing 11 is used to introduce hot gas 18 into the fluidized bed through the perforated fluidized bed 17 is equalized in its speed of entry. In the third section 28 also becomes hot gas 18 introduced, the temperature or speed of the empty pipe can be different. In the fourth section 29 becomes from the fluidized bed room 19 cooled gas 21 , mixed with dried solid particles 30 deducted. The cycle gas blower 31 on the one hand ensures the solids circulation of dried grains 30 in the centrifuge dryer from 29 to 26 , but also for the transport of at least some of the dried solid particles to the separator 32 , which is shown as an example as a cyclone. The exhaust air freed from the solid 33 is partly due to the blower 34 the washer 35 fed. The greater part of the dedusted exhaust gas 36 with hot flame gases 37 mixed again by the blower 38 sucked in and back to the centrifuge dryer 11 pressed. The hot flame gases 37 are in the gas heater 39 through a burner 40 that generates the fuel 41 burns with low levels of excess oxygen. Part of the scrubbed exhaust gas 43 is used as a low-oxygen cooling gas 44 around the burner 40 the gas heater 39 reintroduced and gets back into the gas cycle. The excess gas content 45 is called dusted and washed exhaust gas 46 blown out of the system through the chimney. That in the centrifuge dryer 11 evaporated water is in the scrubber 35 condensed by cooling and with the wash water 48 removed and removed from the dryer circuit.

Like in the EP 0591 299 described in more detail arises from the constant supply of oxygen-poor flame gases 37 and by removing wet exhaust gases 45 from the drying system a circulating gas atmosphere that is greatly depleted by CO ₂ self-inerting in the oxygen content 33 on. This will cause dust explosions and spontaneous combustion of dry products at risk of fire prevented. That in the separator 32 separated dry product 30 is, for example, via a rotary valve 50 discharged. The one in the drying room 19 formed larger granules 23 sink to the fluidized bed 17 and are carried by the screw conveyor 24 and the discharge lock 51 discharged from the dryer. The two dry products, coarser pellets 52 and smaller pellets 53 , can be mixed together or processed separately for different purposes. In this combined centrifuge dryer according to the invention, the pellet sizes can be specifically controlled by the possible setting parameters and produced in the desired grain sizes.

4 shows schematically in longitudinal section a combination of a solid bowl centrifuge 1 with a centrifuge dryer with only the solids discharge and spray zone 5 the centrifuge .1 in the surrounding centrifuge dryer 11 is integrated. In this embodiment, the centrifuge 1 radially ejected solid spray 6 a hot gas stream from below 15 counter-directed in order to brake the solid particles quickly downwards. The solids discharge zone is on both sides of the drum jacket of the centrifuge 5 rotating, self-cleaning impeller wheels open to the outside 20 attached, which to the solids discharge openings 4 constantly suck the gas sideways and at the drop zone 5 create a strong negative pressure. The negative pressure 55 towards the environment of the dryer room 19 causes particle-laden gas in the discharge zone from the fluidized bed 5 flows rapidly radially from the outside to the inside, the solid spray that is thrown out 6 with its moist and sticky particles facing in the opposite direction. The countercurrent of hot gas and fine dry particles decelerates the moist solid particles very quickly, envelops them and dries them in a very short time. Due to the very high relative speed that occurs, extremely high heat and mass transfer rates are achieved. As a result, the specific water evaporation capacity and volume-related dryer capacity are greatly increased. This transfer performance cannot be achieved in a normal fluid bed dryer. The relative speed between hot gas and moist particles in a normal fluidized bed dryer according to the prior art is approximately 1-2 m / s, whereas relative speeds of 30 to 60 m / s are achieved in this arrangement according to the invention. Due to the geometrical design and the corresponding gas velocity, the centrifuge dryer can be operated in continuous operation with a single gas passage, but it can also be operated with a side gas and product outlet in cycle gas operation. Will the gas permeable perforated plate 17 to even out the speed of the incoming drying gas 15 omitted as in 6 , the opening angle 54 of the dryer housing 11 above the hot gas line 16 be reduced in size and the centrifuge dryer builds higher.

In 5 is a centrifuge dryer with a vertically arranged solid bowl screw centrifuge 1 shown as a solid spray machine in the fluidized bed. Instead of the solid bowl screw centrifuge 1 a nozzle decanter or a nozzle separator with a vertical axis could also be installed. The solid bowl screw centrifuge 1 is through the two rolling bearings 3 stored below and above. The frame 66 for the upper camp 3 is led through the solid fluidized bed as a cross. The solid bowl screw centrifuge 1 becomes the liquid sludge 8th over an insulated line 7 fed. The separated liquid 9 flows over a central chute below 10 out, the pre-dewatered solid is inside the fluidized bed as a solid spray 6 from the solids discharge openings 4 thrown out. The fluidized bed shields the dryer walls due to the many moving particles 11 from the wet spray 6 from. The hot gas 15 is from below through import shafts 16 under the fluidized bed 17 pressed in and occurs evenly 18 into the fluidized bed 19 on. Through heating pipes in the fluidized bed 55 heat is returned to the hot gas, which cools down due to water evaporation, and the touching solid particles are also passed through the heating pipes 55 Transfer heat. This measure significantly increases the volume-related evaporation rate. The smaller dried solid particles 53 are via a height-adjustable raid weir 56 discharged. The dusty exhaust gas 21 leaves through the suction pipe 22 the centrifuge dryer. Coarser particles sunk in the fluidized bed 52 can with a slit weir directly above the fluidized bed 17 be dissipated. The height of the fluidized bed 58 is near the spray zone 6 highest, in the direction of flow to the dryer outlet 56 there no 6 highest, in the direction of flow to the dryer outlet 56 the layer goes 58 slightly lower due to the slope.

In 6 is a combined centrifuge dryer in cross section as a combination of the solid discharge of a solid bowl screw centrifuge 1 with a circulating fluidized bed dryer 11 shown without perforated plate bottom.

The centrifuge dryer shown is constructed similarly to that in 4 , however, the circulating fluidized bed being formed 59 mainly above the centrifuge rotor 1 , In the lower half 57 around the centrifuge rotor 1 is the velocity of the hot gas entering 15 at 62 so high that all pre-dewatered solid particles thrown down 6 from hot gas 15 be swept up immediately. The dryer housing 61 around the solids drop zone 5 around is like the diffuser part of a gas venturi built up open. The narrowest point in the Venturi nozzle 62 for the hot gas 15 replaces the perforated plate base 17 for the fluidized bed. In the upper conically expanded dryer section 63 a circulating fluidized bed forms 59 out. The larger or even wetter and therefore heavier solid particles 52 sweep in the upper part of the dryer 63 due to the greatly slowed gas velocity, their upward direction of movement changes and they fall back down into the dryer section 61 with higher upward speed. This statistical circulation movement for heavier particles 52 lasts until the particles 53 are sufficiently dried, lighter or decayed and also discharged upwards at 22 and in the subsequent pipeline 64 be transported pneumatically. The part of the dryer housing built around the centrifuge rotor 1 61 is from the remaining parts of the dryer housing 63 . 16 , through the two elastic compensators 65 separated to allow thermal expansion and no vibrations from the centrifuge 1 to be transferred to the adjacent system parts.

It is a detailed front view of the combined centrifuge dryer for the thermal expansion-compliant mounting of the dryer housing 61 of the combined centrifuge dryer on the centrifuge frame 66 shown. The conically expanded dryer housing 61 expands when the dryer heats up compared to the components that remain cold 1 or 66 of the dewatering centrifuge. The dryer housing 61 consisting of the conical walls 61 and the two side walls sealed against the rotating components of the centrifuge 13 and 14 , should extend in all directions in its middle position to the axis of rotation 67 and move along little. It is therefore due to laterally flexible support elements 68 with the cold, rigid frame 66 connected to the centrifuge. When the dryer housing is enlarged, the spring elements act 68 lateral restoring forces affecting the dryer housing 61 hold the original center position in spite of the extension to the turning center. As laterally resilient support elements 68 can serve coiled steel springs, rubber springs, vertical bending bolts, or vertical or inclined leaf springs. The natural frequencies of the housing support 68 Vibration technology must be coordinated so that it is when starting, operating and turning off the centrifuge 1 resonance vibrations and movements cannot occur.

In the zones 70 with the smallest distance from the solid discharge zone 6 from the dryer walls 61 can, besides in 11 described elements, in the drop zone 5 elastically supported rigid baffles 60 , or elastic, resilient or vibrating baffles in themselves 69 be installed, which clean themselves of solid incrustations. The flat or curved baffles 60 . 69 , can also be installed at an angle to the spray level of the solids discharge or, like the encrusted dryer walls 61 . 16 . 63 . 13 . 14 through a drive 71 be put into cleaning vibrations. To keep the rotor clear 1 nearby housing walls 61 can these be flowed behind and perforated, vibrate, guided gas flows or targeted gas jets can also be used.

7 shows a system diagram for self-inerting cycle gas operation with a centrifuge dryer 49 with circulating fluidized bed 6 and a pretreatment of the suspension 8th through external dry material backmixing 73 in the liquid mud. The centrifuge dryer 49 consists of the dewatering centrifuge 1 or 87 and is used by the hot gas generator 39 with burner 40 over the pipe 16 supplied with hot gas from below. The dried product is through the suction tube 22 to the cyclone separator 32 transported and removed there from the gas cycle. The dedusted exhaust gas 33 is from the cycle gas blower 31 into an exhaust gas component 43 to the washer 35 and into a cycle gas component 36 back to the hot gas generator 39 promoted and with the flame gas 37 from combustion to drying gas 15 mixed. If the dried product fails 30 is via a cross flow classifier 74 who the product 30 cools at the same time, the fine fraction 75 and dust of the product 30 through cross air 76 aspirated and to a separator 77 transported, which is exemplified as a cyclone, but also z. B. operated a dust filter or a scrubber with liquid sewage sludge can be. The continuously accumulating in the separator 77 separated fine fraction 75 is through the discharge lock 51 continuously the suspension 8th mixed. If necessary, the suspension enriched with drainage-promoting granular dry matter can also contain precipitants or flocculants 78 for better clarification in the centrifuge 1 . 87 , added. The dedusted exhaust air 79 also becomes the washer 35 fed for final cleaning. The exhaust fan 34 sucks the entire amount of exhaust gas 45 to the fireplace 80 , The suitable proportions of exhaust gas can be adjusted using control valves 81 to be controlled. The COz - self-inertization and condensation of the moisture is similar to that in 3 described.

In 8th is in longitudinal section and in 9 the associated cross-section shows a combined centrifuge dryer with a rotating fluidized bed and internal continuous material return. The hot gas 15 occurs in several longitudinal sections 27 . 28 through tangentially attached insertion shafts 16 between the dryer housing 11 and the cylindrical or frustoconical perforated fluid bed cylinder 83 rotating one. Due to the tangential inflow process and the type of perforation of the screen cylinder 83 , in the form of slits, beads, Conidur sheets or, for example, grid-shaped inlet openings, the tangential Inflow of the hot gas 18 and forced its rotation inside. The pre-dewatered solid is discharged through the discharge openings 4 the rotating drum 2 sprayed at one end of the drying room. Around the damp spray 6 from the front wall 13 To keep close is a conical or bowl-shaped baffle ring 84 on the front wall 13 or on the drum 2 attached, which deflects the spray in the axial direction. Inside the cylindrical perforated sheet 83 a rotating gas-solid fluidized bed is formed 85 from the incoming rotating hot gas 18 will be carried. The layer thickness that forms 86 the rotating solid fluidized bed 85 is dependent on the grain sizes, the centrifugal field strength, the gas entry speed, the transport speeds in the axial and tangential direction and the centrifugal swarm density. The solid spray 6 from the inside onto the rotating fluidized bed 85 sprayed on and enlarged the already rotating solid particles. Since the radial flow velocity of the particles can be greatly increased by the centrifugal field without the particles being immediately carried away, the heat and mass transfer rates achieved are in the rotating fluidized bed 85 much higher than in a fluidized bed in the earth's gravity field. The fluidized, rotating fluidized bed 85 migrates in the axial direction through the dryer to the suction pipe 22 at the end of the dryer. About the particle concentration and the layer thickness of the rotating fluidized bed 85 near the drop zone 5 will increase at 29 Deducted dry particles and at 26 returned to the fluidized bed. The deduction 29 and the introduction 26 can also be done in the tangential direction. The solid blower takes care of the return transport of the gas / solid mixture 31 , The perforated inner cylinder 83 can also partially consist of solid sheet metal rings or be interrupted by them. The directions of rotation of the centrifuge drum 2 and the rotating fluidized bed 85 can be the same or opposite.

In 10 is a schematic longitudinal section of a combined centrifuge dryer 49 as a combination of solids discharge from a screen screw centrifuge 87 shown with two different filtrate outlets. The screen centrifuge dryer 49 consists of the with its solid discharge 4 centrifuge rotor protruding into the dryer 91 , with an outlet 10 for the mechanically separated clarifying liquid 9 , the conical housing 93 for the screen filtrate 92 and a solid discharge zone 5 at the end of the sieving zone 91 , The housing 11 the centrifuge dryer 49 is divided into several sections in the axial direction for hot gas introduction 16 , Product outlet 61 , Screen filtrate housing 93 , Central chute 10 , The suspension 8th with precipitant if necessary 78 mixed, the screen screw centrifuge 87 through an inlet pipe 7 added and enters the rotating separation space at 88. In the full jacket part 2 the centrifuge sediments the solid onto the drum jacket 2 , the clarifying filtrate 9 is used in DC centrifuges 87 via return channels, in countercurrent centrifuges directly into the center chute via end wall openings 10 hosed. The one from the screw 89 on the cone to the inside of the sieve 90 the centrifuge transported pre-dewatered solid drained on the rotating sieve 91 further residual liquid. This so-called screen filtrate 92 is through the sieve 91 out into the screen filtrate housing 93 flung and flows in 92 from. The screen screw centrifuge 87 is able to mechanically dehumidify very large solid mass flows as far as the fine-grained solids through the rotating sieve 91 can be held back. The one over the sieve 91 snail solid is at the solid discharge 4 flung out on the armored rotating impact cone 103 agglomerates are crushed, distributed in the circumferential direction and slightly deflected and come in after the cross flow 107 in the drop zone 5 with the inflowing hot gas 15 in touch. The baffle cone behind 84 is exemplary here as a combination of a rotating impact cone 103 for distribution in the circumferential direction and an outer, non-rotating deflection cone 84 shown. All hosed solid particles 6 are up in the dryer 19 carried away and in the upper part of the dryer diffuser 63 slowed in speed, similar to in 6 , The rotating sieve 91 can be designed as a cylindrical or slightly conical strainer basket. It can be designed as a welding gap sieve, loop sieve or as a laser finely perforated sheet and consist of wear-resistant stainless steel, ceramic or hard metal. The slope of the screw conveyor 89 can in the sieve part 90 the centrifuge should be smaller than in the solid jacket section 2 , Inside the strainer 91 can washing liquid or superheated steam 82 or hot gas can be introduced to mechanical dehumidification in the sieve section 91 improve and around the solid 6 preheat for subsequent drying.

The screen screw centrifuge, which is mostly used in processing technology, is able to mechanically mechanically scale very large solid mass flows of approx. 50 t / h and more to high TR values of e.g. B. with coal to dehumidify approx. 82% TR, provided that the fine-grained solids can be retained by the sieve. It can also be due to solid waste 4 a race track, not shown, with tangential solid exit upwards or with partial shielding on the sides or downwards according to the state of the art. The particles 6 come in the drop zone 5 with the inflowing hot gas 15 in contact with a high relative speed of 50 - 80 m / s and dry very quickly on the surface in milliseconds. All hosed solid particles 6 are up in the dryer 19 swept away and then slowed down to about 5 - 15 m / s. The applicable temperatures of the incoming hot gas 15 are very high up to 500 ° C because the rotating centrifuge rotor is thermally very well shielded by the diffuser-dryer housing 61 and the conical screen filtrate housing 93 , The hot dryer housing 61 is mechanical due to the elastic expansion compensators 65 completely decoupled from the dryer components and is due to the thermal insulation 95 shielded. The hot dryer housing 61 . 94 is also thermal from the cold screen filtrate housing 93 Cut. To block the rotating screen basket 91 due to the sieve filtrate contaminated with solids 92 a washer device is to be prevented 96 inside the sieve filtrate housing 93 appropriate.

11 shows a longitudinal detail view from a design drawing similar to that 4 . 6 . 10 , for thermal expansion of the combined centrifuge dryer 49 on the centrifuge frame, to seal the hot housing walls 13 and 14 of the combined centrifuge dryer 49 against the rotating centrifuge components and to distribute the solid spray 6 over the entire dryer cross section.

The housing end walls are slightly displaceable due to thermal expansion 13 and 14 are over elastically deformable heat-resistant multi-layer fabric expansion joints 97 with the rigid maze carriers 99 tightly connected. The labyrinth bearers 99 are rigid with the centrifuge frame 66 screwed and carry the non-contact labyrinth seals set with a narrow gap against the rotor parts 100 , The labyrinth bearers 99 are like the roller bearing housings 3 rigid with the supporting centrifuge frame 66 connected, which creates the narrow, non-contact labyrinth gaps 101 also with thermal expansion or movements of the dryer housing 13 ; 14 . 61 . 94 do not change or the rotating rotor surfaces of the centrifuge 1 . 87 can't touch.

The hot, stretching dryer housing 13 . 14 . 61 . 94 is about for example 4 laterally resilient bolts 102 on the cold centrifuge frame 66 attached so that despite thermal expansion of the hot dryer housing similar to that in 6 described the narrow labyrinth column 101 remain constant.

For better distribution of the from the centrifuge solid discharge 4 solid particles thrown out 6 over the entire dryer cross-section and to avoid encrustation of the dryer housing 61 . 94 near the rotor 1 . 4 , is a two- or multi-acting rotating impact device 103 above the individual solids discharge openings 4 appropriate. Due to the multiple impact and deflection of the trajectory of the solid particles 6 after leaving the discharge openings 4 on baffle plates connected in series 103 larger clumps of solids are crushed more easily and the spray is distributed better in the circumferential direction.

The impact and deflection device 103 can be arranged concentrically one above the other on the entire circumference in the radial direction, or above each discharge opening 4 of the centrifuge rotor 1 is a single impact and baffle 104 with different directions and angles 105 appropriate. The different discharge openings 4 can be distributed not only on the circumference, but also in the axial direction over the flow cross section of the dryer.

This will remove the pre-dewatered solid particles 6 over the entire width of the dryer housing and in the hot gas flowing in from below, for example 15 distributed more evenly and with a lower area concentration.

The impact and deflection device 103 . 104 can be a combination of several deflecting elements, which all rotate or consist of a combination with alternating rotating and non-rotating impact elements.

The deflection angle 105 of the individual impact elements 104 can contribute to the better spatial distribution of the centrifuge drum 4 hosed solid mist with each impact element 104 be executed differently.

The orientation of the deflection surfaces can also in the axial direction, twisted to, in or opposite to Direction of rotation take place as possible good spatial Volume distribution of the sprayed solid mist in the hot gas flowing through to reach.

Every single discharge opening 4 for the solid 6 can be operated by at least one impact element for directional distraction.

The impact surfaces 104 can have wear protection in the form of attached hardboard or welded layers.

The centrifuge dryer is as described in the above 1 - 10 executed, the solid spray 6 in the drying room well distributed by the drying gas 15 taken and above the rotor 1 . 87 be dried.

12 shows a longitudinal section through the spray zone 5 of the combined centrifuge dryer 49 after the 4 . 6 . 7 . 10 . 11 , as a multifunction machine with an additional dispersing aid by means of a fan wheel 20 with pin mill 106 and impact cone 84 and second hot gas inlet 18 due to the non-rotating impact cone, which is open at the bottom 84 , For particularly sticky, from the centrifuge 1 mechanically pre-dewatered products 6 is an additional crushing of the ejected solid particles 6 advantageous.

Due to the subsequent comminution of the solid particles, which is superimposed on the drying process 6 new surface is constantly being created, which is exposed to the inflowing hot gas and leads to rapid drying of even very poorly pre-dewatered products.

By on the rotor 2 the centrifuge 1 located fan blades 20 large quantities of hot gas are constantly thrown into the discharge zone 5 and through the crushing tools 106 guided. The impact cone open at the bottom 84 also conducts part of the drying gas flowing in from below 15 through the annular gap 107 in the discharge and shredding zone 5 , The ratio of the two quantities of drying gas flowing in from below 15 . 18 can be varied. The partial flow can also be used, for example 18 one with solid dust 75 be loaded hot gas stream, its solid for coating and coating the sticky solid particles 6 serves to change their adhesive properties.

An example is a pin mill as a shredding unit 106 with two fixed and one with the fan blades 20 shown rotating pin row. Of course, several rows of pins can also be arranged. The shredding unit can also be used in special cases 106 omitted and the rotating fan blades 20 with the opposite direction of conveyance increase suction through the annular gap 107 and act in an extended form as a shredding and scraping tool for the incrustations on the impact cone surface 84 ,

13 shows a view of the completed system with a very high throughput of a combined centrifuge dryer 49 with a circulating fluidized bed dryer 63 , with a second night dryer 108 before - and a press pelletizer 109 after the double cyclone separator 32 ,

If the very low residual moisture of the end product is required or if the mass flow is very large, it may be necessary to extend the residence time and contact time of the solid 6 with the hot drying gas 15 until separation in the cyclone 32 to ensure. An extended contact time from that of the dewatering centrifuge 1 . 87 hosed solid particles 6 with that from the gas heater 39 heated, from below through the pipeline 16 in the centrifuge dryer 49 imported drying gas 15 , is in the above the centrifuge dryer 49 attached fluid bed dryer 63 with circulating fluidized bed 59 given as in the 6 . 7 . 11 explained in more detail.

The drying gas 21 then conveys the dried product to another after dryer 108 in which the residence time of the product is artificially extended.

In the shown Zig-Zag night dryer 108 becomes the product-laden gas stream 21 redirected several times. The solid particles follow for reasons of inertia 6 With a thousandfold mass density compared to the gas, the deflection movements are only partially. They beat on the outer canal surfaces 110 on the wall and are slowed down considerably. They reflect there again and cross the hot gas flow at high relative speeds before each new impact 21 , Due to the large relative speed of the particles 6 to the drying gas 21 The drying speed of the solid particles becomes approx. 20 m / s 6 more than tenfold compared to post-drying in a pneumatic conveyor tube dryer according to the state of the art. The residence time of the solid 6 in the post dryer shown 108 is increased drastically. During the deceleration and re-acceleration phases on each channel curve 110 drying is particularly intensive. The particle distribution in the drying gas 21 The preferably rectangular channel cross section is improved. The formation of highly concentrated product strands in round pipe cross sections, which has been very damaging to the drying speed up to now, is prevented according to the invention even with large pipe dimensions. For washing and cleaning purposes, there is a cleaning flap on the lowest elbow after the downward section 72 intended. After the upward part of the apparatus 108 the pneumatic conveyor pipe is again at the level of the cyclone inlet. This Zig Zag night turner 108 is very effective due to the simply bent sheet metal walls 110 Very inexpensive to manufacture and easy to integrate into the system.

The post-dried product 30 is then in the double cyclone shown 32 separated and through the rotary valve 50 ejected from the gas cycle. From the cellular wheel sluice 50 becomes the powder 30 directly to a press granulator 109 passed, the cylindrical compact from the powder 52 forms by the screw conveyor 24 be transported away. The dedusted drying gas 36 will, as in 3 . 7 , described by the circulating gas blower 31 again mostly the hot gas generator 39 fed. A small part is called exhaust gas 43 fed to the scrubber, not shown, and then as chimney gas 45 released into the environment.

1.

Solid bowl screw centrifuge

Second

Zentrifugentrommel- coat

Third

roller bearing

4th

solid discharge openings

5th

drop zone for the solid fuel

6th

vorentwässerter thick matter

7th

mud pipe for the suspension feed

8th.

Suspension, liquid mud

9th

separated, clarified liquid

10th

Zentratschurre

11th

outer dryer housing

12th

inner casing

13th

bulkhead

14th

bulkhead

15th

drying gas

16th

Hot gas line

17th

gas-permeable perforated sheet, Fluidised bed

18th

hot gas

19th

drying room

20th

blower

21st

cooled drying gas

22nd

suction tube

23rd

Larger solid particles

24th

screw conveyor

25th

impact surfaces

26th

section in the dryer housing

27th

section in the dryer housing

28th

section in the dryer housing

29th

section in the dryer housing

30th

dried Solid particles

31st

Cycle gas blower

32nd

separators for solid

33rd

exhaust free of solids

34th

fan

35th

washer

36th

exhaust dusted

37th

flame gas from combustion

38th

fan

39th

gas heater

40th

burner

41st

fuel

42nd

deleted

43rd

exhaust

44th

cooling gas

45th

fireplace gas

46th

exhaust

47th

ascending speed of the drying gas

48th

wash water

49th

centrifugal dryer total

50th

rotary

51st

airlock

52nd

Coarser pellets

53rd

smaller pellets

54th

Diffuser opening angle

55th

heating pipes for drying gas and fluidized bed

56th

Overflow weir

57th

Lower half the fluidized bed

58th

Height of the fluidized bed

59th

circulating fluidized bed

60th

Baffles vibrate superimposed

61st

Dryer housing diffuser part

62nd

Dryer case tightest Job

63rd

Oberer dryer part

64th

pipeline

65th

vibratory compensators

66th

centrifuges frame

67th

axis of rotation the centrifuge

68th

Edition of pads yielding laterally

69th

Baffles in resiliently compliant

70th

Zone with the narrowest flow cross-section

71st

Cleaning drive

72nd

cleanout

73rd

Trockengut- remixing

74th

Sifter and cooler

75th

fines of the product

76th

cross and cooling air

77th

dust collector

78th

flocculants

79th

exhaust

80th

stack

81st

control valves

82nd

superheated steam

83rd

screen cylinder with tangential openings

84th

baffle plate not rotating

85th

fluidized bed rotary

86th

layer thickness

87th

Screen bowl

88th

inlet chamber

89th

centrifuges screw

90th

phloem the centrifuge

91st

strainer

92nd

screen filtrate

93rd

Siebfiltratgehäuse

94th

conical dryer wall

95th

thermal insulation

96th

washer nozzles

97th

fabric expansion

98th

deleted

99th

labyrinth carrier

100th

labyrinth seal

One hundred and first

labyrinth column

102nd

springy support bolts

103rd

impactor

104th

Impact- and baffle

105th

tilt angle of the baffle

106th

shredding unit

107th

annular gap

108th

Zig- Zag night dryer

109th

Preßgranulator

110th

impact surfaces

Claims (70)

Process for the combined dewatering and drying of suspensions, for example industrial or sewage sludge, fermenter broths or slurries, with a centrifuge, for example a continuous solid bowl screw centrifuge or sieve solid bowl centrifuge, at the entrance zone of which the suspension is applied as a pumpable mass and at the solid discharge zone the Pre-dewatered, sticky thick matter with a high residual moisture content is thrown off in the form of dispersed particles, and with a drying device for convective drying of the thrown off solid particles, the drying device forming a structural unit with the centrifuge and the dryer housing at least partially enclosing the centrifuge, and that the solids waste zone the centrifuge is used as an atomizing machine and as a direct entry element into the dryer, characterized in that the solid particles from the centrifuge in a verb rider dropped zone, reversed in their flight direction directs and distributed in the drying room, the solid waste zone of the centrifuge is at least partially surrounded by a high particle concentration in the drying room, and the moist particles thrown off the centrifuge meet partially already dried recirculated solid particles of the moving surrounding fluidized bed. A method according to claim 1, characterized in that the Solid particles after leaving the centrifuge for better distribution deflected in different directions in the surrounding dryer room become. A method according to claim 1, characterized in that the Speed of the drying gas after flowing around the dewatering centrifuge is reduced. A method according to claim 1, characterized in that above the spray zone the centrifuge has a circulating fluidized bed with extended residence time for the larger particles for drying. A method according to claim 1, characterized in that the Deflection of the solid particles in the dryer room takes place by gas flow. A method according to claim 1, characterized in that the Deflection of the solid particles in the dryer room by impact on resting baffles he follows. A method according to claim 1, characterized in that the Deflection of the solid particles in the dryer room by impact on at least temporarily moving baffles. A method according to claim 1, characterized in that the Redirection of the solid particles in the drying room by multiple Impact occurs on stationary and moving baffles. A method according to claim 1, characterized in that by the multiple deflection of the solid particles also a crushing process be subjected. Method according to Claim 1, characterized in that that the spray zone at least partially within a fluidized bed of whirled solid particles lies. A method according to claim 1, characterized in that the Solid spray the centrifuge onto the particle surfaces of the fluidized bed surrounding it sprayed becomes. A method according to claim 1, characterized in that the Solid spray the centrifuge from above onto the surface of the moving fluidized bed sprayed becomes. A method according to claim 1, characterized in that in or near the spray zone granulation of the particles in the fluidized bed takes place. A method according to claim 1, characterized in that itself the fluidized bed at an angle to the axis of rotation of the centrifuge between 0 ° and Moved 180 °. A method according to claim 1, characterized in that the dryer walls from the spray of Centrifuge are shielded by the fluidized bed particles. A method according to claim 1, characterized in that in the spray zone the centrifuge is already blown dry particles together with hot gas or be sprinkled. A method according to claim 1, characterized in that by Repatriation of Dry product and gas nearby the spray zone the moving fluidized bed is filled with dry solid particles. A method according to claim 1, characterized in that the Fluidized bed is divided into several zones with different ones Fumigation and flow rates. A method according to claim 1, characterized in that the Fluidized bed is divided into several temperature zones. A method according to claim 1, characterized in that at least Parts of the dryer walls and or deflection surfaces gas permeable perforated and ventilated are. A method according to claim 1, characterized in that at least some of the wall surfaces coming into contact with the dispersed solid particles mechanically or be cleaned by blowing with gas. A method according to claim 1, characterized in that the solid to be dried is preheated inside the centrifuge. A method according to claim 1, characterized in that out the drying space at least in two places the dried solid is brought out. A method according to claim 1, characterized records that in the drying room the superficially moist particles from the centrifuge are coated with dry dust. A method according to claim 1, characterized in that in Three- or multi-phase centrifuges at least one of the solid phases be treated like this. A method according to claim 1, characterized in that coarse material agglomerates because of the longer Drying time can be recirculated. A method according to claim 1, characterized in that after the spray zone a sifter for coarse material for extension after the dwell time. A method according to claim 1, characterized in that the Selection by size in the drying room he follows. A method according to claim 1, characterized in that the spray zone close to the centrifuge rotor of hot gas Flows transversely in the axial direction becomes. A method according to claim 1, characterized in that before or between several deflection devices for the solid hot gas is supplied. A method according to claim 1, characterized in that the Solid is washed in the centrifuge with hot water from the exhaust air washer. A method according to claim 1, characterized in that before or hot steam in the centrifuge is mixed into the suspension. A method according to claim 1, characterized in that before the centrifuge is mixed into the suspension to promote drainage become. A method according to claim 1, characterized in that fine dust of the dried product is mixed into the suspension. A method according to claim 1, characterized in that after a hot gas supply to the centrifuge dryer at least once more into the dryer line. A method according to claim 1, characterized in that the Centrifugal dryer is equipped with a diffuser dryer part. A method according to claim 1, characterized in that after the centrifuge dryer another night dryer with an extended one Dwell time for the Solid is connected downstream. A method according to claim 1, characterized in the existence Partial flow of the hot gas passed the centrifuge dryer and only after drying is fed in before the product separator. A method according to claim 1, characterized in that the dehydrated and dried solid is used as fuel for power generation and then Use of hot Exhaust gases for drying. A method according to claim 1, characterized in that the dehydrated and pelletized dried solid. A method according to claim 1, characterized in that the dehydrated and then dried solid is gasified. A method according to claim 1, characterized in that the The dried solid is separated selectively to save fuel Use of the let-through fine dust for energy generation in the hot gas generator for drying and for fine dust removal. Device for performing the method according to a of claims 1 to 42, with a drainage device for draining and drying suspensions with a centrifuge, preferably a solid bowl screw centrifuge or sieve solid bowl screw centrifuge for mechanical separation of a suspension, with an inlet for feeding the Sludge and with at least one outlet each for the separated liquid and the drained Thick matter, the thick matter waste zone of the centrifuge and forms the entry organ in the centrifuge dryer with means to maintain a high concentration from the thrown off Thick matter particles and prolonged Exposure time, characterized in that the rotating centrifuge drum at least with their solids discharge part within the centrifuge dryer is installed, the solid feeder forms and with the Dryer forms a structural unit. Device according to claim 43, characterized in that the Centrifuge in its axial direction at an angle to the horizontal between 0 ° and 180 ° installed is. Device according to claim 43, characterized in that the drying space built around the centrifuge with at least one gas inlet at one end of the centrifuge axis and at least one gas outlet is provided at the opposite end of the centrifuge axis. Device according to claim 43, characterized in that the Gas inlet and the gas outlet only lie on the solids discharge side of the centrifuge axis. Device according to claim 43, characterized in that parts the rotating centrifuge drum in relation to the surrounding fluidized bed, for example are covered by a partial protective jacket. Device according to claim 43, characterized in that this dryer housing thanks to stretchable, movable and non-contact seals the rotating surfaces the centrifuge is sealed. Device according to claim 43, characterized in that this dryer housing supported by elastic elements on the centrifuge frame that are stretchable is. Device according to claim 43, characterized in that this dryer housing is provided with a joint for rotor assembly. Device according to claim 43, characterized in that in particular in the case of sieve screw centrifuges, for example, a conical second filtrate is installed. Device according to claim 43, characterized in that this dryer housing partly from the outside is heated. Device according to claim 43, characterized in that within of the dryer heating elements are installed. Device according to claim 43, characterized in that on Gas inlet in the perforated bottom of the centrifuge dryer, which is divided into individual sections. Device according to claim 43, characterized in that in the perforated bottom is a transport device with an outlet for the coarse material is installed. Device according to claim 43, characterized in that openings of the fluidized bed for circular gas passage, are square, slit-like, bead-like or grid-floor-like and that that free opening ratio in the individual areas is varied. Device according to claim 43, characterized in that on the centrifuge rotor in addition to the solids discharge openings at least one for the introduction of suitable impeller is attached to dry solid particles. Device according to claim 43, characterized in that on the centrifuge rotor rotating discs, turbulence blades or crushing bat are attached. Device according to claim 43, characterized in that on the centrifuge rotor near the solids discharge openings at least one co-rotating wear-protected two-part Impact cones or directed individual impact elements with different Deflection angles are attached. Device according to claim 43, characterized in that itself on the centrifuge rotor near the solids discharge openings one rotating and non-rotating elements existing shredding unit located. Device according to claim 43, characterized in that on the centrifuge rotor over the individual solids discharge openings of the rotor armored crushing and deflection plates with different Deflection angles are attached. Device according to claim 43, characterized in that on the centrifuge rotor next to the solid waste discharge openings a standing race track with rotating fluidized broaching elements and directional output is attached. Device according to claim 43, characterized in that several Solids discharge openings are offset from one another in the axial direction on the centrifuge rotor. Device according to claim 43, characterized in that at the dryer walls moving or vibrating impact elements are attached. Device according to claim 43, characterized in that the dryer walls partially made of gas permeable flowed through from behind Elements. Device according to claim 43, characterized in that in individual zones of the dryer walls mechanical or pneumatic cleaning elements are installed. Device according to claim 43, characterized in that this dryer housing is connected to the gas lines by vibration compensators. Device according to claim 43, characterized ge indicates that the dryer housing has the narrowest flow cross-section at the gas inlet. Device according to claim 43, characterized in that before the solids separator for that Dry product at least one after-dryer with cross-sectional expansions, Kinks, impact zones for the solid particles are connected downstream of the centrifuge dryer. Device according to claim 43, characterized in that the After-dryer is double-running.