WO2017046722A1

WO2017046722A1 - Cogeneration process and plant with gasification of organic material

Info

Publication number: WO2017046722A1
Application number: PCT/IB2016/055484
Authority: WO
Inventors: Massimo GAZZETTA
Original assignee: Clausius - Key S.R.L.
Priority date: 2015-09-16
Filing date: 2016-09-15
Publication date: 2017-03-23
Also published as: EP3350288A1; JP2018534410A; ITUB20153666A1; CN108350368A; US20180258355A1

Abstract

The invention relates to a cogeneration process with gasification of organic material, comprising the steps of: - loading only organic material into a collection tank (10); - supplying at least part of said organic material to a gasification reactor (20); - producing Syngas in said gasification reactor (20) through gasification of at least part di said organic material supplied to said gasification reactor (20); - filtering said Syngas; - supplying the filtered Syngas to at least one internal combustion engine (50); - generating electrical energy by means of an electric generator (60) connected to said at least one internal combustion engine (50). The production of Syngas in said gasification reactor (20) is carried out at a reaction temperature comprised between about 1200 °C and about 1300 °C as a result of a forced injection of combustion air in said gasification reactor (20) and of a generation of whirling movements and/or turbulences of said combustion air in said gasification reactor (20). The invention also relates to a cogeneration plant (100) with gasification of organic material.

Description

COGENERATION PROCESS AND PLANT WITH GASIFICATION OF

ORGANIC MATERIAL

DESCRIPTION

The present invention relates to a cogeneration process with gasification of organic material. The invention also relates to a cogeneration plant with gasification of organic material. Such a plant is suitable for carrying out the aforementioned process.

Throughout the present description and in the subsequent claims, the term "cogeneration" is used to indicate a process/plant for producing electrical energy and heat. The heat can be used for heating buildings and/or in other production-industrial processes. At least part of such heat can also be used in the same process to achieve heat recovery.

As known, gasification is a chemical-physical process that makes it possible to convert organic material into a so-called "Syngas".

Syngas is a combustible gas that typically comprises carbon monoxide, hydrogen, methane and/or other gaseous compounds.

Throughout the present description and in the subsequent claims, the term organic material is used to indicate any organic compound in which the percentage of carbon is at least about 4 %.

In gasification processes of the prior art, only biomass is typically used as raw material.

Such gasification processes typically comprise the steps of loading the biomass into a collection tank, supplying the biomass to a gasification reactor, producing Syngas in the gasification reactor through gasification of the biomass supplied to the gasification reactor and supplying Syngas to an internal combustion engine typically connected to an electric generator.

The Syngas, before being supplied to the internal combustion engine, is filtered to reduce the content of unwanted elements such as so- called "char" (which is a carbonaceous solid very similar to coal), so-called "tar" (which is a harmful liquid to the plants and which typically comprises aromatic hydrocarbons of the tarry type, carbon dioxide and nanoparticulate) and pitchy elements.

The Applicant has observed that the cogeneration processes with gasification of the prior art have some critical aspects.

In particular, the Applicant has observed that, in cogeneration processes with gasification using biomass, the tar, char and pitchy elements are only reduced by up to 35-55 %, for which reason the internal combustion engine must be subjected to frequent scheduled maintenance, typically after only 250-350 working hours.

Moreover, the reaction temperature in the gasification reactor is typically below 800 °C and at such temperatures dangerous pollutants like dioxin form.

The Applicant has also observed that, in order to reach higher reaction temperatures, accelerant substances are typically added in the gasification reactor to the biomass and the combustion air. Such accelerant substances are, however, relatively expensive.

Furthermore, due to the relatively high cost of biomass, the production cost is high.

The problem at the basis of the present invention is to improve the efficiency of cogeneration processes with gasification of organic material in terms of maintenance, emissions into the environment and cost.

The present invention therefore relates, in a first aspect thereof, to a cogeneration process with gasification of organic material, comprising the steps of:

- loading only organic material into a collection tank;

- supplying at least part of said organic material to a gasification reactor;

- producing Syngas in said gasification reactor through gasification of at least part of said organic material supplied to said gasification reactor;

- filtering said Syngas; - supplying the filtered Syngas to at least one internal combustion engine;

- generating electrical energy by means of an electric generator connected to said at least one internal combustion engine;

characterized in that the production of Syngas in said gasification reactor is carried out at a reaction temperature comprised between about 1200 °C and about 1300 °C as a result of a forced injection of combustion air in said gasification reactor and of a generation of whirling movements and/or turbulences of said combustion air in said gasification reactor.

Advantageously, by reaching temperatures of between about

1200 °C and about 1300 °C, all dioxin is destroyed.

According to the invention, the aforementioned temperatures are reached thanks to the effect of the forced injection of combustion air in the gasification reactor and to the generation inside the reactor of whirling movements and/or turbulences of the air. In this way, it is also possible to avoid the use of substances to accelerate the gasification reaction, with relative cost saving.

A further cost saving is obtained thanks to the fact that it is possible to use, as raw material, not only biomass but also a very wide range of organic material less expensive than biomass, like for example: farming waste, pollen, organic waste, urban waste, plastic, rubber, etc....

The organic material which is used can have any percentage moisture and any calorific value.

For a correct and reliable operation, it is preferable to store different types of organic material in different collection tanks, each time using only the materials of one specific tank.

The yield of the cogeneration process according to the invention is almost the same irrespective of the type of organic material being used. The only thing that changes is the amount of organic material being used.

The process of the present invention can have one, or any combination, of the following preferred features. Preferably, said reaction temperature is comprised between about 1250 °C and about 1300 °C.

Preferably, said forced injection is carried out through at least one centrifugal fan.

Preferably, the cogeneration process according to the invention comprises a step of loading solid residues into said collection tank, said solid residues being extracted from said gasification reactor during, or after, the production of the Syngas,.

Such loading can be carried out manually or, preferably, automatically, with known mechanical means, like for example conveyor belts, Archimedean screws, etc.... In this way, the solid residues can always be put back into circulation in the cogeneration process according to the invention, thus substantially eliminating the production of waste material. Such a provision is particularly advantageous if it is considered that the spaces for collecting waste material are increasingly rare, extremely complicated to find and to maintain.

Preferably, filtering said Syngas comprises a first filtration in at least one turbulator filter and a second filtering in at least one activated carbon ceramic filter.

More preferably, the filtering of said Syngas comprises a subsequent filtering in at least one non-woven fabric filter.

Advantageously, the Applicant has found that thanks to the aforementioned filtering, the tar, char and pitchy elements are reduced by about 80-90 %, and therefore to a much greater extent than what occurs in the prior art.

Preferably, the activated carbon ceramic filter comprises activated carbons that have a minimal micrometry, so as to hold further nanoparticles and the pitchy elements and aggregates that pass through the previous filters.

Preferably, the non-woven fabric filter is the last passage and comprises a microfiber fabric that eliminates the last particles of particulate, char and tar. The particulate, nanoparticles, tar and char that are captured in the different filters discussed above, being organic, are collected and put back in circulation in the cogeneration process according to the invention. In particular they are supplied to the collection tank.

Preferably, the cogeneration process according to the invention comprises a step of supplying exhaust gases generated by said at least one internal combustion engine to said collection tank.

The exhaust gases of the internal combustion engine are thus recovered and blown into the collection tank of the organic material in order to contribute to reducing the relative moisture of the organic material itself, by up to 30-45 %, therefore increasing the overall yield of the entire process.

In a second aspect thereof, the present invention relates to a cogeneration plant with gasification of organic material, comprising:

- a collection tank of only organic material;

- a gasification reactor of at least part of said organic material for the production of Syngas;

- supply means for supplying at least part of said organic material into said gasification reactor;

- a filtering unit for filtering said Syngas;

- at least one internal combustion engine located downstream of said filtering unit;

- at least one electric generator connected to said at least one internal combustion engine;

characterized in that the plant comprises forced injection means for the forced injection of combustion air in said gasification reactor and, inside said gasification reactor, means for generating whirling movements and/or turbulences of said combustion air to reach inside said gasification reactor a reaction temperature comprised between about 1200 °C and about 1300 °C.

Such a plant has advantages totally analogous to those discussed above with reference to the cogeneration process of the invention. The cogeneration plant of the present invention can have one, or any combination, of the following preferred features. Such features can be used individually or in combination with any of the features discussed above with reference to the cogeneration process of the invention.

Preferably, said forced injection means comprise at least one centrifugal fan.

Preferably, said means for generating whirling movements and/or turbulences comprise ducts and/or confined passages for said combustion air.

Preferably, the cogeneration plant according to the invention comprises supply means for supplying solid residues into said collection tank, said solid residues being extracted from said gasification reactor during, or after, the production of the Syngas.

Preferably, said filtering unit comprises at least one turbulator filter and at least one activated carbon ceramic filter.

More preferably, said filtering unit also comprises at least one non- woven fabric filter.

Preferably, the cogeneration plant according to the invention comprises a conduit for supplying exhaust gases into said collection tank, said exhaust gases being generated by said at least one internal combustion engine.

Further characteristics and advantages of the invention will become clearer from the description of a preferred embodiment thereof, made with reference to the attached drawings, wherein:

- figure 1 is a schematic view of a cogeneration plant with gasification of organic material according to the present invention;

- figure 2 is an exploded schematic perspective view of a component of the cogeneration plant of figure 1 ;

- figure 3 is an exploded schematic perspective view of another component of the cogeneration plant of figure 1 ;

- figure 4 is an exploded schematic perspective view of a further component of the cogeneration plant of figure 1 . With reference to the attached figures, reference numeral 100 wholly indicates a cogeneration plant with gasification of organic material according to the present invention.

The cogeneration plant 100 comprises a collection tank 10 of only organic material, a gasification reactor 20 of the organic material for the production of Syngas and supply means 30 for supplying the organic material into the gasification reactor 20. In particular, the supply means 30 are associated, at a first end portion thereof, with a lower portion of the collection tank 10 and, at an opposite end portion thereof, with an upper portion of the gasification reactor 20.

The collection tank 10 is hermetic.

Downstream of the gasification reactor 20 the cogeneration plant 100 comprises a filtering unit 40 for filtering the Syngas and, downstream of the filtering unit 40, a plurality of internal combustion engines 50 (in the non-limiting example of figure 1 , there are four internal combustion engines).

The cogeneration plant 100 further comprises an electric generator 60 connected to the internal combustion engines 50 and provided for producing electrical energy. Such energy, before being used, passes through rectifiers and frequency stabilizers of the energy itself.

In the aforementioned cogeneration plant 100 it is possible to carry out the cogeneration process described below.

The organic material is loaded into the collection tank 10 through per se known (and therefore not illustrated) loading means, like for example Archimedean screws, hydraulic pistons, conveyor belts or mats, etc. Such loading means are preferably contained in compartmentalized structures with controlled inlet of air.

From the collection tank 10 the organic material is supplied directly into the gasification reactor 20 through the supply means 30. Such supply means 30 can for example comprise an Archimedean screw, hydraulic pistons or a conveyor belt, all preferably inserted in fluid-tight chambers. The supply means 30 are controlled by a gearmotor 32. In accordance with the present invention, at the gasification reactor 20 forced injection means 22 for the forced injection of combustion air into the gasification reactor 20 are provided. Such forced injection means 22 preferably comprise one or more centrifugal fans 24 (in the non-limiting example of figure 1 , there are two centrifugal fans).

Inside the gasification reactor 20 there are means for generating whirling movements and/or turbulences of the combustion air. Such means are designed so as to allow a reaction temperature comprised between about 1200 °C and about 1300 °C, preferably between about 1250 °C and about 1300 °C, to be reached inside the gasification reactor 20.

The means for generating whirling movements and/or turbulences preferably comprise ducts and/or confined passages, made inside the gasification reactor 20, for the combustion air.

Inside the gasification reactor 20 the pre-drying, drying, pyrolysis and gasification steps of the organic material occur.

The triggering of the reaction occurs through the combustion air injected by the centrifugal fans 24 and the heat generated, for example, by electrical resistances.

The centrifugal fans 24 are controlled by flow rate probes and angular speed sensors. The centrifugal fans 24 make a desired amount of combustion air flow inside the gasification reactor 20. Said amount is calculated by a suitable programme and dependent on the type of organic material, the quality of the external air and the temperature,.

Once the gasification step of the organic material has been reached, a check of the temperature and pressure of the Syngas, as well as a check of the cleanliness of the filtering unit 40, is carried out.

If the checks are positive, the Syngas is supplied through a pipe 25 to the filtering unit 40.

In the non-limiting example illustrated in figure 1 , the filtering unit 40 comprises two filtering stations 42 and 44 connected in series by a pipe 41 . The filtering station 42 comprises a plurality of filtering units 43 (in the non-limiting example of figure 1 , there are four filtering units 43). In the filtering station 42 a heat exchange between Syngas and water or air is also carried out. For this purpose, at least one of the filtering units 43 comprises a tube bundle.

Thanks to the aforementioned heat exchange, the cogeneration plant 100 produces heat energy for about 260 KW, which preferably is used to heat buildings and/or in other production-industrial processes.

In the tube bundle it is possible to circulate water coming, at least in part, from a water tank where the condensate generated by the organic material present in the collection tank is collected. Such water is at a lower temperature than the Syngas that travels inside the filtering units 43, and therefore lowers the temperature of the Syngas itself. In this case, the nanoparticles present in the Syngas become heavier and fall to the bottom of the filtering unit 43.

On-board the filtering units 43 there are pressure transducers and temperature probes.

The state of cleanliness of the filtering units 43 is monitored through pressure transducers that control the inlet-outlet pressure difference in the filtering units 43 themselves. When an inlet-outlet pressure difference greater than the one which is pre-set is detected, the filtering unit 43 is replaced.

The four filtering units 43 are connected in parallel between an inlet manifold 43a and an outlet manifold 43b. Each filtering unit 43 is comprised between an inlet valve 43c and an outlet valve 43d, which are arranged downstream of the inlet manifold 43a and upstream of the outlet manifold 43b, respectively. The valves 43c and 43d, for example of the ball type, are controlled by servomotors.

The four filtering units 43 operate in redundancy, i.e. two are active and two remain in stand-by. The latter work only in the case of an emergency. Such an emergency is detected through pressure transducers. If the pressure transducers detect a pressure drop, the inlet and outlet valves 43c and 43d of the clogged filtering unit 43 are closed and the inlet and outlet valves 43c and 43d of the emergency filtering unit 43 are opened. In this way, the cogeneration plant 100 does not need to be shut down for the cleaning of clogged filters.

The Syngas coming from the gasification reactor 20 contains a large amount of tar, char and pitchy elements. Passing through the filtering station 42, the Syngas is subjected to a reduction of the temperature (for example from about 800 °C to about 600 °C) by means of the water circulating in the tube bundle, to a big reduction of tars contained therein (for example by 60 %) and to a purification and heightening of the methane contained therein.

Each filtering unit 43 comprises a turbulator filter. The filtering unit 43 comprises in particular a plurality of propeller turbulators 43e (for example eleven propeller turbulators having a total surface of 0.60 m² with eight revolutions), preferably made of stainless steel (for example steel AISI 316), which are preferably completely covered in raw ceramic (figure 3). As discussed above, a further function of the filtering unit 43 is that of an air/water heat exchanger. For example, an inner chamber of the filtering unit 43 can have a content of about 43 I of water with a heating production of 48 kW.

The turbulator filter has a dual function:

1 ) it creates a turbulence that, given the low production pressure of the Syngas, ensures that the nanoparticles deposit on the bottom of the filter by banging or cyclone function;

2) the ceramic captures all of the pitchy elements by adherence.

From the filtering station 42, the Syngas is sent to the filtering station 44.

The filtering station 44 comprises a plurality of filtering units 45 (in the non-limiting example of figure 1 , there are four filtering units 45).

The four filtering units 45 are connected in parallel between an inlet manifold 45a and an outlet manifold 45b. Each filtering unit 45 is comprised between an inlet valve 45c and an outlet valve 45d, which are arranged downstream of the inlet manifold 45a and upstream of the outlet manifold 45b, respectively. The aforementioned inlet and outlet valves 45c and 45d, for example of the ball type, are controlled by servomotors.

On-board the filtering units 45 there are pressure transducers and temperature probes.

The four filtering units 45 operate in redundancy, i.e. two are active and two remain in stand-by and work in the case of an emergency. Such an emergency is detected through pressure transducers. If the pressure transducers detect a pressure drop, the inlet and outlet valves 45c and 45d of the clogged filtering unit 45 are closed and the inlet and outlet valves 45c and 45d of the emergency filtering unit 45 are opened.

Each filtering unit 45 comprises an activated carbon ceramic filter. In particular, such a filter comprises irregular solids of raw ceramic inserted in a substantially cylinder-shaped basket.

The filtering unit 45 carries out a primary collection of condensate through a forced air passage: in particular, the flow passes in a pack of active carbons and, in immediate sequence, in baskets of raw ceramic and in perforated hollow cylinders 45e with a high porosity (figure 4). The condensate is discharged by opening a condensate discharge valve 45f. The filtering unit 45 can also comprise a non-woven fabric filter and/or a gravitational ceramic filter. In the latter, the flow of Syngas is introduced from the lower parts of filtering cylinders coated in raw ceramic and is made to rise: the nanoparticles, having a specific weight higher than air, fall by gravity and aggregate at the bottom of the filter, as well as to solids in raw ceramic.

Through the filtering station 44, 70 % of tar, char and other pitchy elements are eliminated.

From the filtering station 44, the Syngas is sent to the internal combustion engines 50 through a pipe 51 . The internal combustion engines 50 are connected to the electric generator 60 through a galvanic joint. The electric generator 60 is for example a permanent magnet alternator. The internal combustion engines can be internal or external combustion engines.

The cogeneration plant 100 comprises a conduit 52 for supplying into the collection tank 10 the exhaust gases generated by the internal combustion engines 50. Such exhaust gases, due to their high temperatures, substantially lower the moisture (by up to 20-35 %) of the organic material present in the collection tank 10, thus increasing the yield of the organic material itself. The supply of exhaust gases into the collection tank 10 takes place at controlled pressure.

Alternatively or in addition to the aforementioned provision, depending on the power of the cogeneration plant 100, the cogeneration plant 100 can comprise, upstream of the gasification reactor 20, a pre- drying line for pre-drying the organic material. Such a pre-drying line comprises a hermetic and insulated tunnel.

The length of the possible pre-drying line is calculated on the basid of the heat power developed by the exhaust gases of the internal combustion engines 50.

For a power of 199 kW, for example, the pre-drying line is a structural tunnel (for example made of steel Fe360) of a length of about 12 m. The tunnel is for example externally coated by self-supporting metal panels micro-ribbed on both sides and internally insulated by polyurethane.

An anallergic and corrugated rubber conveyor belt slides inside the tunnel to improve the adherence of the materials.

Preferably, such a belt is fastened to hollow rollers, for example made of stainless steel AISI 304, to the ends of which toothed wheels are connected, joined together through a metallic chain. The whole is moved by gearmotors.

At the entrance to the pre-drying line, a ground-level scraping and slewing unit is arranged to bring the organic material closer to the entrance of the tunnel and of the conveyor belt. At the end of the pre-drying line, preferably two syncopated Archimedean screws insert the load of organic material into the gasification reactor 20 in alternate steps.

On the walls of the tunnel there are holes to which the manifolds are connected, for example having a diameter of 1 14.3 mm, for example made of stainless steel AISI 304, for the possible recovery of the exhaust gases of the internal combustion engines 50, with the relative insufflation of the exhaust gases inside the tunnel itself.

From the pre-drying line, the organic material is introduced directly inside the gasification reactor 20.

The moisture collected in the pre-drying line can be collected in a tank and used in the tube bundle provided in the filtering unit 43, as described above. The heated water in the filtering unit 43 can stay in the circuit, becoming purified and evaporating due to the various thermal shocks which is subjected to.

The cogeneration plant 100 also comprises supply means 70 for supplying into the collection tank 10 solid residues extracted from the gasification reactor 20.

The supply means 70 are associated, at one end thereof, with an Archimedean screw 72 (figure 2) configured to bring the solid residues outside of the gasification reactor 20. Such an Archimedean screw 72 is located in a lower portion of the gasification reactor 20 and moves the solid residues until they reach a compartment 74. Such solid residues are from here taken back into the collection tank 10 through the supply means 70.

As can be seen from figure 1 , the cogeneration plant 100 - unlike the prior art - is substantially a closed circuit, and therefore substantially nothing goes out from the circuit.

The environmental impact of the cogeneration plant 100 is therefore substantially zero. The cogeneration plant 100 uses substantially all of the energy power of the organic material, until it is made innocuous, transforming it almost entirely (up to 95 %) in a single Syngas cycle. The remaining 5 % of the organic material is collected as residue from the gasification reactor 20 and is reinserted into the collection tank 10, so as to carry out a second cycle and complete its transformation into Syngas.

The size of the cogeneration plant 100 is extremely small and this makes it easy to transport, as well as being of great interest to users that do not have a lot of space available.

The interventions to be carried out on site to install the cogeneration plant 100 are not particularly onerous and essentially concern the preparation of the space in which the cogeneration plant 100 has to be installed, the connection of the collection tank(s) 10 of the organic material to the gasification reactor 20 and the various electrical connections.

With reference to the storage of the organic material in the collection tanks 10, such tanks are modular and the loading of the organic material takes place with a completely automated system controlled by software, just like the entire operation of the cogeneration plant 100, which can be constantly monitored remotely.

When the cogeneration plant 100 is started, a test is carried out on all of the mechanical, electrical and electronic components to check that they are in optimal working order. For example, level probes, temperature probes, flow rate probe, pressure transducers, servomotors and permanent magnet alternator, are subjected to testing.

This step is carried out in a predetermined and adjustable time, at the end of which a unit for managing and controlling the cogeneration plant 100 receives data from the level probe arranged inside the gasification reactor 20.

If the level signal is low, the gearmotor 32 associated with the supply means 30 is actuated and the organic material is supplied from the collection tank 10 and/or from the pre-drying line to the gasification reactor 20. Once a maximum load level, detected by a suitable level probe provided inside the gasification reactor, has been reached the gearmotor

32 is stopped. At the time when the desired load of organic material is reached in the gasification reactor 20, the centrifugal fans 24 begin to operate at maximum angular speed for a predetermined time to wash the pipes provided for transporting the Syngas. At the end of this cycle, one of the two centrifugal fans 24 is switched off, whereas the other decreases the angular speed to a variable level depending on the programme inserted in the management and control unit, the program being dependent on the type of organic material introduced into the gasification reactor 20.

Such adjustment is dictated by the calorific and hygrometric capacity of the organic material. At the same time, the contacts of the electrical resistances of the gasification reactor 20 close and remain in such a mode until the desired temperature is reached, detected by a temperature probe. Such a temperature is variable from 400 to 700 °C. Once such a temperature is reached, the contacts are reopened.

The angular speeds of the centrifugal fans 24 are adjusted through flow rate probe(s), so as to introduce the required amount of air into the gasification reactor 20.

The temperature probe(s) have the function of transmitting data to the management and control unit, in order to signal possible emergency conditions (high temperatures above the established limit for that specific point of the cogeneration plant 100), causing the intervention, wherever an emergency condition has been reached, of suitable safety members controlled by the management and control unit to stop the cogeneration plant 100.

As far as the treatment of the Syngas produced in the gasification reactor 20 is concerned, it follows a path in which the various filters discussed above are provided, all in redundancy, so that, through control by pressure transducers, the state of the filters is continuously monitored.

In an autonomous manner, the management and control unit commands the closing of the clogged filters and the opening of the free ones. When this happens, the management and control unit sends a warning to the operator for the cleaning of the clogged filters, giving a predetermined time (for example 3 days) beyond which the management and control unit stops the cogeneration plant 100 for safety reasons.

As an example, with an organic material of a mixture of arundo chips and plastic, a Syngas is obtained comprising N2 (47 % by volume), CO (18 % by volume), CO2 (8 % by volume), H2 (16 % by volume) and CH₄ (9 % by volume).

As stated above, in order to obtain a constant and reliable energy production yield, it is recommended to supply a specific collection tank 10, and from this the gasification reactor 20, with a single type of organic material for each production cycle. However, the cogeneration plant 100 can also work in the case in which a mixture of different organic materials is used in each cycle.

The cogeneration plant 100 according to the invention, as well as being particularly environmentally-friendly, is also economically profitable. Indeed, considering that energy costs are increasingly high and a greater burden on citizens, such a plant allows electrical energy to be produced, which can be used to reduce the management costs (for example the costs of communal administrations that has common parts or buildings, schools, kindergartens, communal offices, small first aid stations and small hospitals or even small artisans) and increase profitability as well as competitivity. Thanks to such production of electrical energy, and considering that, as well as electrical energy, the plant offers about double the production of completely free heat energy, which can be used to heat various kinds of environments, the entire plant can be amortized in 4 or 5 years at most.

For farming areas the advantages are even clearer. Indeed, by law tree or grass trimmings cannot be burnt. They should be discarded, at one's own cost, in authorized landfills. Those who own the cogeneration plant 100 according to the invention can be of great help to farmers or woodsmen, by not making them pay to dispose the waste and perhaps giving them a small payment deriving from the production of energy in exchange. Of course, those skilled in the art can bring numerous modifications and variants to the invention described above, in order to satisfy specific and contingent requirements, all of which are in any case covered by the scope of protection of the present invention as defined by the following claims.

Claims

1 . Cogeneration process with gasification of organic material, comprising the steps of:

- loading only organic material into a collection tank (10);

- supplying at least part of said organic material to a gasification reactor (20);

- producing Syngas in said gasification reactor (20) through gasification of at least part of said organic material supplied to said gasification reactor (20);

- filtering said Syngas;

- supplying the filtered Syngas to at least one internal combustion engine (50);

- generating electrical energy by means of an electric generator (60) connected to said at least one internal combustion engine;

characterized in that the production of Syngas in said gasification reactor (20) is carried out at a reaction temperature comprised between about 1200 °C and about 1300 °C as a result of a forced injection of combustion air in said gasification reactor (20) and of a generation of whirling movements and/or turbulences of said combustion air in said gasification reactor (20).

2. Cogeneration process according to claim 1 , wherein said reaction temperature is comprised between about 1250 °C and about 1300 °C.

3. Cogeneration process according to claim 1 or 2, wherein said forced injection is carried out by means of at least one centrifugal fan (24).

4. Cogeneration process according to any one of the previous claims, comprising a step of loading solid residues into said collection tank (10), said solid residues being extracted from said gasification reactor (20) during, or after, the production of the Syngas.

5. Cogeneration process according to any one of the previous claims, wherein filtering said Syngas comprises a first filtration in at least one turbulator filter (43) and a second filtration in at least one activated carbon ceramic filter (45).

6. Cogeneration process according to claim 5, wherein filtering said Syngas comprises a subsequent filtration in at least one non-woven fabric filter.

7. Cogeneration process according to any one of the previous claims, comprising a step of supplying exhaust gases to said collection tank (10), said exhaust gases being generated by said at least one internal combustion engine (50).

8. Cogeneration plant (100) with gasification of organic material for performing a process according to claim 1 , said cogeneration plant (100) comprising:

- a collection tank (10) of only organic material;

- a gasification reactor (20) of at least part of said organic material for the production of Syngas;

- supply means (30) for supplying at least part of said organic material in said gasification reactor (20);

- a filtering unit (40) for filtering said Syngas;

- at least one internal combustion engine (50) located downstream of said filtering unit (40);

- at least one electric generator (60) connected to said at least one internal combustion engine (50);

characterized in that the plant comprises forced injection means (22) for the forced injection of combustion air in said gasification reactor and, inside said gasification reactor (20), means for generating whirling movements and/or turbulences of said combustion air to reach in said gasification reactor (20) a reaction temperature comprised between about 1200 °C and about 1300 °C.

9. Cogeneration plant (100) according to claim 8, wherein said forced injection means (22) comprise at least one centrifugal fan (24).

10. Cogeneration plant (100) according to claim 8 or 9, wherein said means for generating whirling movements and/or turbulences comprise ducts and/or confined passages for said combustion air.

1 1 . Cogeneration plant (100) according to any one of claims 8-10, comprising supply means (70) for supplying solid residues to said collection tank (10), said solid residues being extracted from said gasification reactor (20) during, or after, the production of the Syngas.

12. Cogeneration plant (100) according to any one of claims 8-1 1 , wherein said filtering unit (40) comprises at least one turbulator filter (43) and at least one activated carbon ceramic filter (45).

13. Cogeneration plant (100) according to claim 12, wherein said filtering unit (40) comprises at least one non-woven fabric filter.

14. Cogeneration plant (100) according to any one of claims 8-13, comprising a conduit (52) for supplying exhaust gases to said collection tank (10), said exhaust gases being generated by said at least one internal combustion engine (50).