IT201600124645A1 - FILTER FOR THE SEPARATION OF A PARTICULAR SUBSTANCE, IN PARTICULAR CARBONIAL PARTICULAR, BY A SYNTHESIS GAS - Google Patents

Description

"FILTER FOR THE SEPARATION OF A PARTICLE SUBSTANCE, IN PARTICULAR CARBON PARTICULATE, FROM A SYNTHESIS GAS"

The present invention relates to a filter for the separation of a particulate substance, in particular carbonaceous particulate, from a synthesis gas.

Plants are known, for example from application TO2013A000332, for transforming organic-based material, for example vegetable biomass, into a synthesis gas, that is, into a gas mixture intended to be oxidized to obtain heat and / or mechanical energy. Synthesis gas essentially comprises carbon monoxide, hydrogen, methane and carbon dioxide.

In greater detail, plants are known comprising a reactor crossed by the air and the organic-based material in a descending direction, i.e. from top to bottom, and within which the chemical reactions that transform the organic-based material take place. in synthesis gas.

The plant essentially includes:

- a feed hopper for the organic-based material;

- an outlet that can be crossed by the synthesis gas and fluidically connected to the user;

- a casing housing the hopper; And

- the reactor, which is housed inside the casing, fed from the hopper with air and organic-based material, and inside which the organic-based material is transformed into synthesis gas.

Proceeding from top to bottom, the reactor of the aforementioned type of plant includes:

- a first layer, in which the organic-based material is dried and ignited, so as to undergo partial carbonization;

- a second layer, in which the organic-based material undergoes a pyrolysis process in the absence of comburent, ie in the absence of air; And

- a third layer, in which the heat generated by pyrolysis is used to completely dissociate the organic-based material and generate the synthesis gas.

It is known in the sector that the synthesis gas leaving the reactor cannot be immediately used by an internal combustion engine, as it contains useless particulate substances or even potentially harmful to the end user, such as carbonaceous particulate matter.

The need is felt in the sector to remove these particulate substances from the synthesis gas, in order to make it usable for the internal combustion engine.

The object of the present invention is to provide a filter for the separation of a particulate substance, in particular carbonaceous particulate, from a synthesis gas capable of satisfying this requirement in a simple and economical way.

The aforesaid object is achieved by the present invention, since it relates to a filter for the separation of a particulate substance, in particular carbonaceous particulate, from a synthesis gas.

For a better understanding of the present invention, a preferred embodiment is described below, purely by way of non-limiting example and with reference to the attached figures, in which:

- Figure 1 illustrates, in part schematically, a unit for the generation of mechanical power that can be fed with synthesis gas, comprising a filter according to the dictates of the present invention;

Figure 2 is a perspective view of a filter for the separation of a particulate substance, made according to the dictates of the present invention;

Figure 3 is a front view of the filter of Figure 2, with parts removed for clarity;

Figure 4 is a front view of the filter of Figures 2 and 3, with parts removed for clarity;

- Figure 5 illustrates in top view the filter of Figures 2 to 4, with parts removed for clarity; and - Figure 6 is a perspective view on a greatly enlarged scale of some details of the filter of Figures 1 to 5, with parts removed for clarity.

With reference to the attached figures, 100 indicates a unit for generating mechanical power starting from a synthesis gas.

Unit 100 essentially includes:

- a plant 1 for the transformation of an organic-based material into a synthesis gas;

- a cyclone 101 and a scrubber 102 (only schematically illustrated in figure 1), which are fed by the plant 1 with the synthesis gas and are able to carry out a first separation of the particulate matter from the synthesis gas;

- a filter 103 (illustrated in greater detail in Figures 2 to 6) and fed by the scrubber 102;

- a cooling unit 104 (only schematically illustrated in Figure 1) and fed by the filter 103 with the synthesis gas; And

- an internal combustion engine 105 (only schematically illustrated in Figure 1), which is fed by the cooling unit 104 with the filtered and cooled synthesis gas.

In the case illustrated, the organic-based material is plant biomass. Alternatively, the organic-based material could be made up of agricultural products deriving from traditional intensive cultivation, suitably chopped, or with squeezing residues of exhausted olives and pomace, husk and / or lulla of rice, grains, maize and cereals in general.

The synthesis gas is a gas mixture intended to be oxidized to obtain heat and / or mechanical energy within a user (not shown), for example an internal combustion engine, located downstream of plant 1. The gas synthesis essentially includes nitrogen, carbon monoxide, hydrogen, methane and carbon dioxide.

Plant 1 essentially includes:

- a hopper 2 for feeding the organic-based material;

- an outlet 3 that can be crossed by the synthesis gas and fluidically connected to the user;

- a casing 4 housing the hopper 2; And

- a reactor 5 housed inside the casing 4, fed by the hopper 2 with air and organic-based material, and inside which the organic-based material is transformed into synthesis gas.

In particular, the hopper 2 includes a chute and is motorized by a motor 17 to facilitate the descent of the organic-based material and distribute the same uniformly inside the reactor 5.

The envelope 4 has a substantially tubular conformation of axis A and is delimited by a pair of cylindrical walls 12, 13 and arranged respectively in a radially internal and external position with respect to axis A.

Preferably, the casing 4 houses a laser sensor that detects the level of organic-based material reached inside the reactor 5, and allows or prevents the loading of the organic-based material inside the hopper 2 on the basis of this level.

The envelope 4 also comprises a truncated-cone-shaped wall 14 made of ceramic material.

The reactor 5 is housed in a substantially coaxial way inside the casing 4.

The reactor 5 has a tubular shape and extends along an axis A, vertical in the case illustrated.

The reactor 5 also comprises an outlet section 7 of the synthesis gas from the reactor 5 itself.

The section 7 is also arranged at a lower level than the hopper 2 and higher than the wall 14.

More specifically, the section 7 of the reactor 5 is arranged at a lower level than the hopper 2.

In this way, the organic-based material proceeds inside the reactor 5 from top to bottom, according to a method known in the industry as "down-draft".

For this purpose, the plant 1 includes a fan (not shown), which keeps the reactor 5 in depression.

Reactor 5 comprises, proceeding from hopper 2 towards section 7,:

- a plurality, three in the case illustrated, of stages 8, 9, 10 superimposed on each other, within which, one after the other, respective reactions of transformation of the organic-based material into synthesis gas take place; And

- a barrier 18 and a grid 19, which obstructs the section 7 of the reactor 5.

The stages 8, 9, 10 are arranged one after the other, proceeding from the hopper 2 towards section 7.

In greater detail, stage 8 is a pre-heating stage, stage 9 is a pyrolysis stage and stage 10 is a stage of complete dissociation of the organic-based material.

Inside stage 8, the organic-based material undergoes a drying and subsequent combustion process in the presence of a comburent, for example hot air. This combustion brings the temperature of the organic-based material inside layer 8 to a value of about 600-700 ° C, favoring the carbonization of the organic-based material, by breaking down the volatiles present in the woody fibers.

Inside stage 9, the partially carbonized organic-based material undergoes a pyrolysis process.

In particular, the pyrolysis process is due to the high temperature and the lack of comburent. In other words, the pyrolysis process occurs in a substantial lack of oxygen.

Following the pyrolysis process, the chemical bonds originating in the organic-based material are disrupted and a gaseous mixture containing aromatic hydrocarbons is formed.

The stage 9 also comprises a pair of grids 20 fixed to the walls 14 and provided to slow down the carbonic material inside the stage 9 itself and thus allow this carbonic material to remain for the necessary time inside the stage 9 itself. .

In particular, the grids 20 are shaped like an inverted double cone and have a plurality of calibrated holes (not shown).

The grids 20 are also effective in preventing the advancement of the ashes, which are formed by the components of aromatic hydrocarbons present in the gaseous mixture.

In the case illustrated, the grids 20 are made of ceramic material.

Stage 10 includes:

- a surface 11 maintained at a temperature of about 1300 ° C by the pyrolysis reaction which takes place in stage 9; And

- a plurality of forced passages (not shown), which guide the gaseous mixture against the surface 11.

Thanks to the high temperature of the surface 11, the volatile components of the gaseous mixture that had not been blocked by the grids 20 are completely dissociated. These volatile components are formed, in particular, by micro carbon powders, which could damage and / or compromise the operation of engines fed with synthesis gas.

In particular, these carbon powders, at the surface 11, react with the water vapor, giving rise to carbon monoxide and hydrogen.

The barrier 18 is formed, in the case illustrated, by alumina spheres.

In particular, the alumina spheres store heat and dissociate the last carbon particles still present in the synthesis gas.

Plant 1 also includes:

- a storage tank 22 for the unburnt waste and the ash removed from the synthesis gas; and - a transfer system 21, which is fed, by gravity, with the unburnt scraps and falling ashes from section 7 of the reactor 5 and transfers the aforementioned scraps and ashes to the tank 22, by means of a system of augers not shown.

The plant 1 comprises cooling means 30 comprising a tube bundle 80 formed by a plurality of tubes 81 crossed by the synthesis gas and embedded within a bath 82 of a thermo-vector liquid, water in the case illustrated.

The tube bundle 80 is located immediately below the section 7 and receives the synthesis gas from the section 7 itself.

In greater detail, the tube bundle 80 extends parallel to axis A between:

- a third share, less than the second share; and - a fourth share, less than the third share.

In greater detail, the tube bundle 80 includes a pair of plates 83, 84 upper and lower, and lying on respective planes parallel to each other and orthogonal to axis A.

The tubes 81 have respective axes parallel to each other and parallel to axis A and extending between the plates 83, 84.

The tubes 81 are welded, at their respective upper and lower ends, to the plates 83, 84.

The plates 83, 84 have respective plurality of holes arranged in correspondence with the open sections of the tubes 81.

In particular, the tubes 81 are arranged inside the tube bundle 80 so as to form, in section orthogonal to axis A, a plurality of concentric circles with respect to axis A itself.

The tube bundle 80 also includes:

- a casing 90, which extends between the plates 83, 84 and defines a volume for the bath 82; And

- a replacement circuit for the heat transfer liquid heated with fresh heat transfer liquid.

The circuit includes, in particular,:

- a plurality of openings 92 defined by the casing 90 and designed to allow the entry and exit of the heat transfer liquid;

- a heat exchanger (not shown) to cool the heat-carrying liquid leaving the bath 82; And

- a hydraulic pump (not shown) to send the cooled heat transfer liquid back into bath 82.

The tube bundle 80 is arranged in a position immediately below the grid 19 and the barrier 18.

In the case illustrated, the plates 83, 84 and the tubes 81 are made of stainless steel.

Thanks to the cooling action of the tube bundle 80, the synthesis gas is cooled to a temperature of about 20 ° C.

Advantageously, the filter 103 comprises (Figures 2 to 5):

- an inlet 110 which can be fed with the synthesis gas rich in the particulate matter;

- an outlet 111 that can be crossed by the synthesis gas, from which the particulate substance has been filtered;

- a rotor 112 defining a chamber 114 for passing through the synthesis gas; And

- a filtering cloth 113, which is applied on the rotor 112, seals the chamber 114 and is suitable for separating the particulate substance of the synthesis gas.

Inlet 110 is fluidically connected to scrubber 102 and chamber 114.

The outlet 111 is fluidically connected to the chamber 114 and to the cooling unit 104.

Inlet 110, chamber 114 and outlet 111 define a fluid path for the synthesis gas.

The filter 103 comprises, in particular, a casing 109 having the shape of a tubular along the C axis.

The envelope 109 defines the entrance 110 and the exit 111.

In the case illustrated, input 110 is radial to axis A and output 111 is coaxial to axis C.

Entrance 110 is also located at a lower altitude than exit 111.

The envelope 109 and the canvas 113 define between them a tubular compartment 140, which is arranged on the opposite side of the C axis with respect to the canvas 113.

The envelope 109 includes, in particular:

- a main section 106 substantially cylindrical and coaxially housing the element 112; And

- an end section 107 protruding from a lower end of the main section 106 and converging downwards.

The main section 106 coaxially houses the rotor 112, the cloth 113 and the chamber 114.

In the illustrated embodiment, the rotor 112 is formed by a plurality of blades 119 having respective axes parallel to the C axis and arranged circumferentially around the C axis itself.

The blades 119 are adapted to prevent the collapse of the cloth 113 during the operation of the filter 103.

The blades 119 are made, in particular, of iron or steel.

Filter 103 also includes (Figure 6):

- a pressing device 160, which is able to press the ply 113 against the blades 119; And

- a net (not shown) interposed between the blades 119 and the cloth 113 to redistribute more uniformly the pressure of the cloth 113 on the blades 119.

More precisely, the filter 103 comprises:

- a tray 161 elongated along the axis A and arranged in correspondence with a portion 162 of the casing 109 from which some blades 119 have been removed;

- a plate 163 elongated parallel to the C axis and opposite the tray 161 and connected to the blades 119; And

- the device 160, which is formed by a bolt screwed onto the plate 163 and onto the tray 161.

Preferably, the cloth 113 is a wire mesh made of sintered steel.

In the illustrated embodiment, the cloth 113 has a filtering capacity ranging from 15 to 20 microns. The filter 103 further comprises a variable speed motor (not shown), which is operatively connected to the rotor 112 by means of a transmission shaft not shown.

Preferably, the exit 111 is arranged at a higher level than the entrance 110.

With reference to Figure 2, the filter 103 also comprises an aspirator 118 arranged at a top of the outlet 111 and a collection device 120 arranged below the inlet 110.

Thanks to this configuration, the synthesis gas rich in particulate matter enters the filter 103 through the inlet 110, flows into the sealed chamber 114 coming into contact with the filter cloth 103, and exits the filter 103 through the outlet 111.

The aspirator 118 creates a direct synthesis gas stream, in this case illustrated from the bottom up, and from inlet 110 to outlet 111.

The filter 103 also comprises a device 115 (Figures 3 and 4) for washing the cloth 113, which is provided to remove the particulate substance from the cloth 113 itself by adding jets of a washing substance onto the cloth 113 itself, in the case illustrated water.

The device 115 comprises, in a first embodiment, a bar 116 elongated parallel to the C axis and arranged between the rotor 112 and the cloth 113. In particular, the washing liquid is ejected at high pressure (70 bar) in equi -current with the rotary movement of the rotor 112 and of the cloth 113.

The bar 116 includes a plurality of nozzles 117, the are arranged on the bar 116 parallel to the C axis.

The bar 116 and the nozzles 117 are fixed with respect to the C axis.

In a preferred embodiment, the filter 103 also comprises a device 124 for the mechanical removal of the particulate matter arranged on the face of the canvas 113 opposite the axis C and the chamber 114 (Figure 5).

The device 124 comprises a brush 125 rotating integrally with the rotor 112 and adapted to clean the cloth 113.

The brush 125 is mounted on a shaft 126 and is arranged adjacent to the ply 113.

Shaft 126 and brush 125 rotate around an axis B, which is parallel to axis C.

The shaft 126 and the brush 125 are arranged externally to the casing 109.

The brush 125 is shaped like a hollow cylinder of axis B and has a generatrix 127, which is elongated parallel to axis B and is instantly placed in contact with the cloth 113 on the opposite side to axis A.

For this purpose, the casing 109 has an opening engaged by the portion 127.

The nozzles 117 of the bar 116 are active together with the brush 125 in a first operating phase of the plant 1, when the amount of particulate matter inside the synthesis gas is particularly high.

In a second phase of operation of the plant 1, ie when the amount of particulate matter inside the synthesis gas is reduced, the nozzles 117 are deactivated and the particulate matter is removed only by the brush 125.

Alternatively, the device 115 is a dry saturated steam generator.

The collection device 120 is defined by the end section 107 of the casing 109.

The collection device 120 comprises (Figure 7): - a first conduit 129 ending in an outlet 130, which is fluidically connected with the compartment 140; And

- a second conduit 131 ending in an outlet 121, which is fluidically connected with the chamber 114.

The particulate substances and the washing liquid collect in the ducts 129, 131 by the action of gravity.

The output 130 is coaxial to the C axis. The output 132 is staggered with respect to the C axis.

The ducts 129, 131 are closed by their respective sealing valves (not shown), to prevent the combustion air outside the filter 103 from reacting with the synthesis gas contained within the filter 103 and damaging the filter 103 itself.

Finally, the filter 103 comprises a plurality of frangible disks 150 (only one of which is shown in Figure 2), should the pressure inside the filter 103 exceed a threshold value.

In use, the carbonic material is inserted into the hopper 2 and from this it reaches the reactor 5 together with a comburent, typically air.

Inside the reactor 5, the carbonic material undergoes a combustion in the presence of the comburent at a temperature of about 600-700 ° C inside stage 8; and undergoes a pyrolysis process inside stage 9 substantially in the absence of air.

In particular, the grids 20 prevent the advancement of the ashes formed by the aromatic hydrocarbons present in the gaseous mixture.

Inside stage 10, the synthesis gas is guided against the surface 11 at a high temperature. In this way, the carbon powders not eliminated by the grids 20 are completely dissociated.

Barrier 18 is effective in removing the last remaining carbon particles still present in the synthesis gas.

The unburnt waste and the ashes removed from the synthesis gas reach, by gravity, the system 21 and are then stored inside the tank 19.

The synthesis gas below crosses section 7 and flows inside the tubes 81 of the tube bundle 80, which are in contact with the bath 82 of heat carrier liquid.

Thanks to the cooling action of bath 82, the temperature of the synthesis gas drops inside the tube bundle 80 to a value of about 40 degrees centigrade

The synthesis gas cooled in a controlled and filtered way reaches the outlet 3 of plant 1 and is made available to cyclone 101 and scrubber 102, within which a first separation of the particulate substances from the synthesis gas is carried out.

Subsequently, the synthesis gas still rich in particulate substances flows from the scrubber 102 to the inlet 110 of the filter 103.

The rotor 112 and the cloth 113 rotate around the axis A. At the same time, the aspirator 118 creates a stream of synthesis gas inside the seal chamber defined by the rotor 112 and by the cloth 113 by the inlet 110 located below. towards exit 111 above.

This current causes the synthesis gas to flow along the wire 113 and to deposit the particulate substance on it.

The blades 119 prevent the collapse of the canvas 113, under the action of the aspirator 118.

The nozzles 117 of the bar 116 are active together with the brush 125 in a first operating phase of the plant 1, when the amount of particulate matter inside the synthesis gas is particularly high.

In a second phase of operation of the plant 1, ie when the amount of particulate matter inside the synthesis gas is reduced, the nozzles 117 are deactivated and the particulate matter is removed by the rotating brush 125 alone.

The washing fluid and the particulate matter removed from the cloth 113 by the nozzles 117 and the brush 125 collect, by gravity, in the respective ducts 130, 131 of the collection device 120.

More precisely, the washing water and the particulate matter contained in the compartment 140 collect in the duct 131 while the washing water and the particulate matter contained in the chamber 114 collect in the duct 132.

The synthesis gas substantially free of particulate matter flows from outlet 111 to the cooling unit 104 and from the latter to the internal combustion engine 105.

From an examination of the filter 103 made according to the present invention, the advantages it allows to obtain are evident.

In particular, the filter 103 comprises a rotor 112 defining the chamber 114 for the airtight passage of the said synthesis gas, and a filtering cloth 113 applied on the rotor 112, sealing the chamber 114 and able to separate the said particulate substance from the said synthesis gas.

In this way, the canvas 113 retains the particulate substance and separates it from the synthesis gas, which flows from inlet 110 to outlet 111.

Furthermore, the washing device 115 continuously removes the particulate matter from the cloth 113. In this way, the cloth 113 remains "clean" during the operation of the filter 103. Consequently, it is not necessary to periodically interrupt the operation of the filter 103 to replace the cloth. 113 "dirty" with a new 113 "clean".

This effect of continuous removal of the particulate matter from the cloth 113 is made particularly efficient by the fact that the rotor 112 drives the cloth 113 in rotation around the axis A and by the fact that the washing device 115 generates a continuous flow of washing flow on the canvas 113 itself.

The extractor 118 allows you to create a direct stream of synthesis gas directed from the bottom upwards and from inlet 110 to outlet 111.

The blades 114 of the rotor 112 support the cloth 113 and prevent its collapse, when the aspirator 118 is activated.

Finally, it is clear that modifications and variations can be made to the filter 103 previously described and illustrated without thereby departing from the scope of protection of the present invention.

Claims (1)

CLAIMS 1.- Filter (103) for the separation of a particulate substance, in particular carbonaceous particulate, from a synthesis gas, characterized in that it comprises: - an inlet (110) which can be fed with said synthesis gas rich in said particulate substance; - an outlet (111) that can be crossed by the said synthesis gas, from which the said particulate substance has been filtered; - an element (112) defining a chamber (114) for which the said synthesis gas is sealed through; And - a filtering cloth (113) applied to the said element (112), sealing off the said chamber (114) and able to separate, in use, the said particulate substance from the said synthesis gas. 2.- Filter according to Claim 1, characterized in that it comprises a casing (109), which defines said inlet (110) and said outlet (111); the said casing (109) housing the said element (112) and the said ply (113); said element (112) being rotatable integrally with said ply (113), preferably at variable angular speed, with respect to said casing (109). 3.- Filter according to Claim 1 or 2, characterized in that the said cloth (113) is made of sintered steel. 4.- Filter according to any one of the preceding claims, characterized in that it comprises washing means (115) suitable for ejecting a stream of a washing fluid onto said cloth (113) to remove said particulate matter accumulated on the cloth (113) itself. 5.- Filter according to Claim 4, characterized in that said washing means (115) comprise at least one nozzle (117) fixed with respect to said casing (109), which is able to eject said washing fluid onto said canvas (113). 6.- Filter according to Claim 4 or 5, characterized in that it comprises a brush (125) adapted to cooperate with said cloth (113) to remove said particulate matter accumulated on said cloth (113); said brush (125) being rotatable with respect to said casing (109); the said washing means (115) being operated, in use, in a first operating step of the said filter (110); the said brush (125) being operated, in the said first operating phase and in a second operating phase of the said filter (110); the said second operative phase being temporally subsequent to the said first operative phase. 7.- Filter according to any of the preceding claims, characterized by the fact that it comprises suction means (118), which are suitable for sucking the said synthesis gas and causing its movement inside the said chamber (114). 8.- Filter according to any one of the preceding claims, characterized in that the said element (112) comprises a plurality of supporting blades (114), which support the said web (113). 9.- Filter according to any one of the preceding claims, characterized in that said outlet (111) is arranged, in use, at a higher level than said inlet. 10.- Filter according to claim 9, when dependent on claims 5 to 8, characterized in that it comprises means (120) for collecting said particulate substance and said fluid, which are arranged below said element (112); the said collection means (120) defining: - a first collection duct (131), which is fluidically connected with said chamber (114); and / or - a second collection duct (119), which is fluidly connected to a compartment (140) delimited between said casing (109) and said canvas (113). 11.- Drive unit (100), comprising: - a plant (1) for the transformation of an organic-based material into synthesis gas; - a filter (103) according to any one of the preceding claims; And - a driving member (105), which can be fed with the said synthesis gas filtered by the said filter (103).