US20110131990A1 - Combustion plant with abatement of pollutants - Google Patents
Combustion plant with abatement of pollutants Download PDFInfo
- Publication number
- US20110131990A1 US20110131990A1 US13/056,706 US200913056706A US2011131990A1 US 20110131990 A1 US20110131990 A1 US 20110131990A1 US 200913056706 A US200913056706 A US 200913056706A US 2011131990 A1 US2011131990 A1 US 2011131990A1
- Authority
- US
- United States
- Prior art keywords
- plant according
- combustion
- fumes
- chamber
- abatement
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/006—General arrangement of incineration plant, e.g. flow sheets
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/08—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating
- F23G5/14—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating including secondary combustion
- F23G5/16—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating including secondary combustion in a separate combustion chamber
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/006—Layout of treatment plant
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
- F23L7/007—Supplying oxygen or oxygen-enriched air
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G2201/00—Pretreatment
- F23G2201/30—Pyrolysing
- F23G2201/301—Treating pyrogases
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G2201/00—Pretreatment
- F23G2201/40—Gasification
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G2202/00—Combustion
- F23G2202/10—Combustion in two or more stages
- F23G2202/102—Combustion in two or more stages with supplementary heating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G2202/00—Combustion
- F23G2202/10—Combustion in two or more stages
- F23G2202/103—Combustion in two or more stages in separate chambers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2215/00—Preventing emissions
- F23J2215/30—Halogen; Compounds thereof
- F23J2215/301—Dioxins; Furans
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2217/00—Intercepting solids
- F23J2217/50—Intercepting solids by cleaning fluids (washers or scrubbers)
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2219/00—Treatment devices
- F23J2219/70—Condensing contaminants with coolers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2219/00—Treatment devices
- F23J2219/80—Quenching
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/32—Direct CO2 mitigation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
Definitions
- the present invention relates to a plant for combustion or incineration of various materials, in particular waste, with abatement and destruction of the pollutant fumes resulting from combustion.
- combustion is meant a process in the presence of air, whether in excess or in defect, with consequent exclusion of the processes based upon the phenomenon of pyrolysis, i.e., in the absence of air.
- the plant according to the invention is conceived for thermodestruction of any combustible material with or without recovery of the thermal energy produced by combustion, but in any case with drastic reduction of the percentages of pollutants in the resulting fumes.
- the present plant finds particular application in the sector of incineration of waste—such as urban solid waste (USW), special waste, industrial waste, and all the solid-fossil and liquid-fossil toxic-noxious derivatives, waste and second-degree raw materials that comprise all the fossil residues, exhausted mineral and vegetable oils, all the residuals of petroleum and fossils of any kind, and tyres for motor vehicles—and of thermodestruction of the pollutant atoms contained in the fumes and incondensables.
- waste such as urban solid waste (USW), special waste, industrial waste, and all the solid-fossil and liquid-fossil toxic-noxious derivatives, waste and second-degree raw materials that comprise all the fossil residues, exhausted mineral and vegetable oils, all the residuals of petroleum and fossils of any kind, and tyres for motor vehicles—and of thermodestruction of the pollutant atoms contained in the fumes and incondensables.
- the plant can be adapted to operate in combination with combustion furnaces of a different type, both ones with variable temperature and ones with controlled and constant temperature, or again rotary furnaces with variable geometry and the like.
- the plant can moreover be adapted according to the materials that are to undergo destruction and the type of energy that it is desired, if possible, to recover, on the basis of the requirements of small and medium-sized industries up to large plants for the systematic destruction of waste, with a recovery of up to 95% of the potential energy contained in the waste.
- incineration systems comprising a furnace for combustion of the material by thermodestruction and a postcombustion device designed for bringing the resulting fumes of combustion to very high temperatures in order to abate the percentage of pollutants, for example dioxins and sulphates, but are totally devoid of separators of CO 2 and condensers for condensing the water contained in the incondensables that are to be destroyed.
- pollutants for example dioxins and sulphates
- pollutants such as CO, SO, SO 2 , HCl, HF, NO, NOx, particulates present in larger amounts, and other noxious components in low concentrations but of high toxicity such as polycyclic aromatic hydrocarbons (PAHs), compounds of heavy metals (mercury, cadmium), organo-chlorinated compounds (polychlorobiphenyls, dioxins, furans).
- PAHs polycyclic aromatic hydrocarbons
- compounds of heavy metals mercury, cadmium
- organo-chlorinated compounds polychlorobiphenyls, dioxins, furans
- furnaces for incineration of waste also known are furnaces referred to as “gasification furnaces”, constituted by a combustion chamber thermally insulated from the outside world and coated on the inside with a refractory material, in which the fuel is burnt using an amount of oxygen that is insufficient for complete oxidation of the material present in order to produce a combustible gas (syngas), which may then be burnt to produce thermal energy to be recovered, for example, via a steam turbine or an explosion engine.
- gasification furnaces constituted by a combustion chamber thermally insulated from the outside world and coated on the inside with a refractory material, in which the fuel is burnt using an amount of oxygen that is insufficient for complete oxidation of the material present in order to produce a combustible gas (syngas), which may then be burnt to produce thermal energy to be recovered, for example, via a steam turbine or an explosion engine.
- syngas combustible gas
- incineration plants based upon alternating-charging rocking furnaces, in which adjustment of the air for the combustion is carried out on the basis of the stoichiometric scale, i.e., by pressure.
- thermodestruction of waste in which a succession of separator modules is used for pre-treatment of the fumes that leave the combustion chamber and that are to go to a postcombustor once they have been deprived of the condensable components, such as water, dust, and carbon dioxide.
- Incineration plants of a known type present numerous drawbacks.
- a first drawback is represented by the fact that the abatement of pollutant fumes does not prove satisfactory unless the postcombustion process is brought up to very high temperatures, this both in energy-recovery plants and in thermodestruction plants for the abatement alone of pollutants.
- a further drawback of incineration systems of a known type is that they present a high energy consumption.
- a further drawback is that incineration systems of a conventional type are unable to burn toxic-noxious waste.
- the purpose of the present invention is to overcome the drawbacks of known incineration systems, and to propose a plant that is able to destroy thermally combustible materials of any type and in particular waste of any kind, at the time same obtaining a level of abatement of the pollutant fumes that is much higher than in known systems, to reach values of concentration of pollutants that are lower than the values required by the relevant standards.
- the plant comprises an assembly for recovery of the energy produced by combustion.
- a second advantage lies in the energy efficiency of the process of thermodestruction of the incondensables.
- a third advantage consists in the adaptability of the plant to different requirements in terms of material to be destroyed, size of the plant, and energy requirements.
- a fourth advantage consists in the possibility of recovering the energy produced by combustion.
- a fifth advantage consists in the possibility of thermodestruction in a continuous process of material that is non-uniform in terms of volume and quality, maintaining the pollutant values of the fumes at output below fixed and pre-set values.
- FIG. 1A shows an example of thermodestruction plant of a traditional type
- FIG. 1 is a schematic representation of a first embodiment of the plant
- FIG. 2 is a schematic representation of a second embodiment of the plant equipped with an energy-recovery assembly
- FIG. 3 shows a preferred embodiment of a module for separation of carbon dioxide according to the invention.
- a plant according to the invention comprising a combustion chamber 1 for combustion of a mass of fuel supplied from a supply mouth 26 .
- the chamber 1 can be constituted by an incinerator furnace, a boiler supplied, for example, with coal or with tyres for motor vehicles, or other device operating by combustion in the presence of oxygen, hence excluding devices which operate by pyrolysis.
- the chamber 1 is connected via a pipe 9 to a postcombustion device 2 for thermodestruction of the incondensable gases generated by combustion, which is also connected, via a pipe 27 , to a supply 21 of air rich in oxygen, preferably for separation of the nitrogen component, in order to maintain optimal carburation of the postcombustor, which is regulated by a control unit 23 and by a regulation valve 24 for modulating the air.
- the postcombustor 2 is constituted by three cylinders and a base, which may also present different shapes, and is equipped with three manifolds: a first one for inlet of gases 43 , which leads to a modulating burner 16 with the function of bringing the postcombustor up to temperature; a second one, i.e., the pipe 9 , which conveys the incondensable gases; and a third one, designated by 19 , for discharge. All the components are preferably made of stainless steel coated on the inside with refractory material 18 having the function of maintaining the internal temperature of the postcombustor itself constant.
- postcombustor 2 may have shapes and characteristics optimized in relation to the constructional design of the plant.
- set along the pipe 9 in an intermediate position between the chamber 1 and the postcombustor 2 is at least one module 4 for abatement, by difference in specific weight, of carbon dioxide and/or carbon monoxide present in the combustion fumes, as also of any other component having a specific weight higher than that of the incondensables, such as LPG, methane, propane, butane, or the like.
- the modules 4 are constituted by a conveyor 8 traversed from top down by the combustion fumes and by a current of water, which is introduced into the cylinder by a piping 12 and laps the flow of fumes, englobing and drawing along with it the carbon dioxide and possible dust, which is conveyed via a drainage pipe 11 into an underlying tank 10 for deposit of waste water.
- the circulation of the water can moreover be assisted by a recirculating pump 17 , which draws from the tank 10 , which is preferably made of stainless steel and is connected to the sewage network, and delivers into the piping 12 .
- module 4 for the abatement of CO 2 , CO, dust, and other components of relatively high specific weight.
- the module 4 has inside it a series of pilot tubes or ducts 44 , which may have different cross sections and shapes according to the requirements and have the function of directing the residue of combustion coming from the chamber 1 through the pipe 9 at inlet to the module 4 .
- the pilot ducts are distributed in at least two diffusers 45 , 47 , which are set in the internal section 46 of the module 4 and are separated by an empty portion 48 of the section 46 .
- the fumes coming from the chamber 9 are distributed and traverse the ducts 44 of the first diffuser 45 , invade the empty portion 48 , and are distributed again and traverse the ducts 44 of the second diffuser 47 .
- the fumes are impinged upon by the water coming from the line 12 and sent into the module 4 preferably through sprayers 49 .
- the incondensable gases increase in volume and enter the module 4 with a specific weight lower than the carbon dioxide, dust, carbon monoxide, and other components, which are impinged upon by the flow of water and precipitated by difference of specific weight through the drainage pipe 11 .
- the presence in succession of a number of diffusers separated by an empty portion enables improvement of the surface of exchange between the fumes to be precipitated and the water, drastically reducing the residual content thereof in the pipe 9 downstream of the module 4 .
- the module 4 in steady running conditions the module 4 is traversed by the “dirty” waste water, pushed by the pump 17 , with the advantage of favouring englobing of carbon dioxide, CO, and dust and their precipitation into the tank 10 , as compared to the use of clear water or mains water.
- a separator module 5 for abatement of the water vapour present in the fumes which preferably comprises a tube-nest exchanger traversed by the fumes and by the recirculating water pushed by the pump 17 , which causes condensation of the steam and falling thereof into a tank 10 preferably made of stainless steel and connected to the sewage network.
- the separator 5 is an air/water separator constituted by two cylinders made of stainless steel or by other suitable material, inside which two nests of pipes are connected, sized so as to be self-cleaning and isolated in a fluid-tight way so as to be traversed by the exhaust fumes without coming into contact with the cooling water that laps the outer surface of the pipes themselves.
- the treatment of separation of carbon dioxide, dust, and water vapour (and possibly nitrogen) from the fumes coming from the combustion chamber 1 makes it possible to limit or eliminate in the postcombustion step the cooling effect otherwise caused by the fumes, and to obtain resulting gases that can be used for a further recovery of heat and of electrical energy and that after postcombustion are rendered altogether harmless.
- any incineration furnace produces dioxins in the combustion chamber already at the temperature of 300° C.; then, as the temperature rises in the combustion chamber, the dioxins previously produced burn but other more resistant ones are produced, and so on until dioxins are produced that to undergo destruction require in known systems the use of postcombustors operating at above 1100° C.
- the pollutant atoms undergo previously a treatment of separation of carbon dioxide and dust and condensation of the water vapours, whilst the incondensables are pushed into the postcombustor and can be burnt at a relatively low temperature indicatively comprised between 600-700° C. or lower, with evident energetic advantage of the thermodestruction process.
- a negative-pressure device 6 is provided set along the piping 9 with inlet of the fumes at the bottom and outlet at the top.
- the negative-pressure device 6 is preferably a extractor with variable r.p.m., or flow regulator, which determines vacuum supply of the plant, i.e., of the combustion chamber 1 , inducing a negative pressure in the upstream pipes, and a positive pressure downstream, with the further effect of aspirating the condensation gases contained in the fumes through the modules 4 and 5 , and pushing the residual incondensable gases into the subsequent stretch of the piping 9 .
- the module 7 is constituted by a cylindrical container 7 , inside which a mixture of water and bicarbonate, soda or the like is present, preferably supplied automatically for neutralizing the acids contained in the incondensables.
- the cylinder 7 is traversed from bottom to top by the fumes coming from the piping 9 and comprises a pump 20 for circulation of the bicarbonate mixture taken from a deposit 19 , which draws in from the tank 10 , the bicarbonate mixture being introduced via a piping 30 into the pipe 9 at inlet to the cylinder 7 .
- the module 7 is traversed by the recirculating water coming from the piping 30 and poured back into the tank 10 via the drainage pipe 11 .
- the number and sizing of the modules 4 , 5 , 6 , 7 is variable and can be optimized on the basis of the type of waste or fuel to be burnt and of the dimensions of the plant, as likewise of the desired application.
- the fumes introduced by the pipe 9 traverse the bicarbonate mixture present in the cylinder 7 and undergo abatement of the acids, which are poured, by now neutralized, into the tank 10 through the stretch of drainage pipe 11 , reaching the top stretch of the pipe 9 without any acid content.
- the pump 20 carries out circulation of the bicarbonate mixture by drawing from the deposit 29 and from the tank 10 via a piping 49 .
- the devices for abatement of the carbon dioxide 4 , water vapour 5 , and hydrochloric acid 7 can be assembled in a replaceable and modular way along said pipe 9 on the basis of the application and size of the plant and the type of fuel introduced into the chamber 1 .
- the pipe 9 conveys the residual incondensable gases into the postcombustor 2 , to carry out thermodestruction thereof, already at temperatures that range from 600 to 700° C.
- the postcombustor 2 finally discharges, via a pipe 19 , the residual fumes, which are by now free from any pollutant content.
- connection pipe 9 before conveying the component of incondensable gases coming from the combustion chamber 1 into the postcombustor, passes through all the separator devices 4 , 5 , 7 , which consequently form a closed circuit of the system.
- a plant according to the invention can comprise a control unit 23 for governing a valve 24 for regulation of the volume of oxygen-enriched air that is to reach the postcombustor 2 on the basis of the values of oxygen content detected by a probe 25 set in the proximity of the outlet of the combustion fumes from the chamber 1 .
- the combustion chamber 1 may consequently be constituted by a furnace for incineration of solid and/or liquid toxic-noxious waste, for example, chemical/pharmaceutical waste, or else again by a boiler for combustion of coal or tyres, or else a converter furnace supplied with liquid fossils, or a furnace for incineration and gasification of urban solid waste (USW).
- a furnace for incineration of solid and/or liquid toxic-noxious waste for example, chemical/pharmaceutical waste
- a boiler for combustion of coal or tyres or else a converter furnace supplied with liquid fossils, or a furnace for incineration and gasification of urban solid waste (USW).
- an energy-recovery assembly 31 set between said combustion chamber 1 and the module for abatement of carbon dioxide 4 .
- the combustion chamber 1 is preferably constituted by a combustion chamber of a gasification furnace 41 for the production of syngases, which does not require supply of air for the combustion because it works in defect of air, but uses only a limited amount of carbon dioxide that serves for transfer of the gases obtained from the furnace 1 to the assembly 31 , without, however, burning the gas produced.
- the assembly 31 comprises a postcombustor 13 , which comprises a modular burner 16 and is supplied via a pipe 50 by the combustion fumes of the chamber 1 and which, in turn, supplies a steam generator 3 provided with an outlet 32 for the steam produced that is to be sent on to a turbine 15 , preferably through a valve 38 , and with an outlet 40 for the residual fumes that are to be sent on to the device for abatement of carbon dioxide 4 .
- a postcombustor 13 which comprises a modular burner 16 and is supplied via a pipe 50 by the combustion fumes of the chamber 1 and which, in turn, supplies a steam generator 3 provided with an outlet 32 for the steam produced that is to be sent on to a turbine 15 , preferably through a valve 38 , and with an outlet 40 for the residual fumes that are to be sent on to the device for abatement of carbon dioxide 4 .
- a second control unit 33 may moreover be provided for governing a valve 34 for regulation of the volume of oxygen-enriched air that comes from the supply 21 and that is to be sent to the postcombustor 2 and/or 13 , which can be modified on the basis of the values of oxygen content detected by the probe 25 set at the outlet from the chamber 1 and by a probe 35 set, instead, in the proximity of the outlet 40 of the combustion fumes from the steam generator 3 .
- a second steam generator 14 can moreover be provided, supplied by the postcombustor 2 and provided with an outlet 36 for the steam produced that is to be sent on to a turbine 15 , preferably through a valve 38 , and moreover connected to the outlet 19 of the pollutant-free exhaust fumes.
- a probe 37 for measuring the contents of the fumes at the exhaust 19 which is connected to the control unit 23 .
- reading of the characteristics of the gases emitted by the plant through the exhaust 19 enables optimization of the combustion temperature that can be obtained in the chamber 1 , in the postcombustor 2 , and in the postcombustor 13 .
- samplings carried out comprised:
- Value ref Limit values Concentration 11% O 2 Daily Half-time mg/Nm 3 mg/Nm 3 mg/Nm 3 mg/Nm 3 HCl 0.022 0.018 10 60 HF N.R. N.R. 1 4
- PCDDs polychlorodibenzodioxins
- PCDFs polychlorodibenzofurans
- PAHs polycyclic aromatic hydrocarbons
- the samples were taken at outlet of the combustion fumes from the postcombustor.
- samplings carried out comprised:
- the postcombustor 13 was programmed in such a way that the gases produced by incineration of the waste were brought, after the last introduction of combustion air and before expulsion into the atmosphere, at a temperature of at least 950° C.
- the invention achieves important advantages.
- the system is pre-arranged for modular solutions, i.e., for providing both in medium-sized and in large-size plants a series of modular and conversion furnaces that can be used also in alternating phases.
- syngas is produced with any waste, for example through a coaxial furnace with programmed and continuous supply through which a high level of functionality and safety is achieved.
- the combustion furnace is a variable-geometry furnace but also because it is supplied with oxygen-enriched air, produced by the device 21 , for example, a device that separates nitrogen from the supply air of the burners, furnaces, heat accelerators, and postcombustors.
- the device 21 for example, a device that separates nitrogen from the supply air of the burners, furnaces, heat accelerators, and postcombustors.
- the plant constitutes a true means of thermal destruction of waste and fumes with continuos variable adjustment at a controlled temperature.
- the plant is suited for obtaining easily the conversion of electric power stations into fossil-carbon power stations.
- the system forming the subject of the present invention enables in fact recovery both of the potential energy of the waste introduced into the combustion chamber and of the resulting incondensables, which form an excellent syngas with a calorific power higher than 516 000 kcal.
- said incondensables by passing through the postcombustor already at temperatures of 600-700° C. are destroyed, as likewise the pollutants contained in the carbon atoms, etc., in such a way that, once freed into the environment, they are altogether harmless and breathable.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Treating Waste Gases (AREA)
Abstract
A combustion plant, comprising: a combustion chamber (1) for combustion of a mass of fuel; a postcombustion device (2) for thermodestruction of the incondensable gases generated by combustion in the chamber (1); a pipe (9) for conveying the combustion fumes from said chamber (1) to said postcombustor (2); a supply (21) of oxygen-enriched air to said chamber (1) and/or to said postcombustor (2); and a device (4) for abatement of the carbon dioxide contained in the combustion fumes that are to reach the postcombustor.
Description
- The present invention relates to a plant for combustion or incineration of various materials, in particular waste, with abatement and destruction of the pollutant fumes resulting from combustion.
- It is emphasized that in the present description by “combustion” is meant a process in the presence of air, whether in excess or in defect, with consequent exclusion of the processes based upon the phenomenon of pyrolysis, i.e., in the absence of air.
- In greater detail, the plant according to the invention is conceived for thermodestruction of any combustible material with or without recovery of the thermal energy produced by combustion, but in any case with drastic reduction of the percentages of pollutants in the resulting fumes.
- It is a system for incineration of waste and thermodestruction of the incondensable gases and dioxins resulting from incineration of any type of waste, including second-degree raw materials that after combustion are discharged into the atmosphere.
- The present plant finds particular application in the sector of incineration of waste—such as urban solid waste (USW), special waste, industrial waste, and all the solid-fossil and liquid-fossil toxic-noxious derivatives, waste and second-degree raw materials that comprise all the fossil residues, exhausted mineral and vegetable oils, all the residuals of petroleum and fossils of any kind, and tyres for motor vehicles—and of thermodestruction of the pollutant atoms contained in the fumes and incondensables.
- In the various possible applications, the plant can be adapted to operate in combination with combustion furnaces of a different type, both ones with variable temperature and ones with controlled and constant temperature, or again rotary furnaces with variable geometry and the like.
- The plant can moreover be adapted according to the materials that are to undergo destruction and the type of energy that it is desired, if possible, to recover, on the basis of the requirements of small and medium-sized industries up to large plants for the systematic destruction of waste, with a recovery of up to 95% of the potential energy contained in the waste.
- In the current state of the art, incineration systems are known comprising a furnace for combustion of the material by thermodestruction and a postcombustion device designed for bringing the resulting fumes of combustion to very high temperatures in order to abate the percentage of pollutants, for example dioxins and sulphates, but are totally devoid of separators of CO2 and condensers for condensing the water contained in the incondensables that are to be destroyed.
- In greater detail, in the fumes that are to reach the atmosphere numerous pollutants are generally present, such as CO, SO, SO2, HCl, HF, NO, NOx, particulates present in larger amounts, and other noxious components in low concentrations but of high toxicity such as polycyclic aromatic hydrocarbons (PAHs), compounds of heavy metals (mercury, cadmium), organo-chlorinated compounds (polychlorobiphenyls, dioxins, furans).
- At the current state of the art, for incineration of waste also known are furnaces referred to as “gasification furnaces”, constituted by a combustion chamber thermally insulated from the outside world and coated on the inside with a refractory material, in which the fuel is burnt using an amount of oxygen that is insufficient for complete oxidation of the material present in order to produce a combustible gas (syngas), which may then be burnt to produce thermal energy to be recovered, for example, via a steam turbine or an explosion engine.
- Moreover known are incineration plants based upon alternating-charging rocking furnaces, in which adjustment of the air for the combustion is carried out on the basis of the stoichiometric scale, i.e., by pressure.
- Known from the Italian patent No. IT1316578 is a system for thermodestruction of waste, in which a succession of separator modules is used for pre-treatment of the fumes that leave the combustion chamber and that are to go to a postcombustor once they have been deprived of the condensable components, such as water, dust, and carbon dioxide.
- This solution has not, however, solved the problem of a complete cleaning and separation of the incondensable gases introduced into the postcombustor and of the temperature necessary to obtain thermodestruction thereof.
- Incineration plants of a known type present numerous drawbacks.
- A first drawback is represented by the fact that the abatement of pollutant fumes does not prove satisfactory unless the postcombustion process is brought up to very high temperatures, this both in energy-recovery plants and in thermodestruction plants for the abatement alone of pollutants.
- In particular, in traditional incineration systems regulation of the air for combustion is performed on the basis of the stoichiometric scale, and hence cannot be performed automatically at any moment, as would be necessary when there is a continuous variation of the characteristics of the waste.
- A further drawback of incineration systems of a known type is that they present a high energy consumption.
- A further drawback is that incineration systems of a conventional type are unable to burn toxic-noxious waste.
- Known postcombustion systems are in fact characterized by a high energy consumption due to the presence in the fumes of carbon dioxide and condensate, which knocks down the temperature necessary for destruction of the noxious fumes.
- The purpose of the present invention is to overcome the drawbacks of known incineration systems, and to propose a plant that is able to destroy thermally combustible materials of any type and in particular waste of any kind, at the time same obtaining a level of abatement of the pollutant fumes that is much higher than in known systems, to reach values of concentration of pollutants that are lower than the values required by the relevant standards.
- According to the invention, the above purpose is achieved with a plant according to Claims 1-14.
- According to a further aspect of the invention, the plant comprises an assembly for recovery of the energy produced by combustion.
- According to the invention, the above purpose is achieved with a plant according to Claims 15-23.
- Further purposes are achieved according to the attached dependent claims. The advantages obtained basically consist in the possibility of destroying any type of material completely, in particular also toxic-noxious waste, with a drastic abatement by thermodestruction of the resulting pollutant fumes.
- A second advantage lies in the energy efficiency of the process of thermodestruction of the incondensables.
- A third advantage consists in the adaptability of the plant to different requirements in terms of material to be destroyed, size of the plant, and energy requirements.
- A fourth advantage consists in the possibility of recovering the energy produced by combustion.
- A fifth advantage consists in the possibility of thermodestruction in a continuous process of material that is non-uniform in terms of volume and quality, maintaining the pollutant values of the fumes at output below fixed and pre-set values.
- The technical characteristics of the invention, according to the aforesaid purposes, emerge clearly from the contents of the annexed claims, and advantages that it affords will become even more evident from the ensuing detailed description and the annexed plates of drawings, wherein:
-
FIG. 1A shows an example of thermodestruction plant of a traditional type; -
FIG. 1 is a schematic representation of a first embodiment of the plant; -
FIG. 2 is a schematic representation of a second embodiment of the plant equipped with an energy-recovery assembly; -
FIG. 3 shows a preferred embodiment of a module for separation of carbon dioxide according to the invention. - With reference to the attached figures, described herein is a plant according to the invention, comprising a
combustion chamber 1 for combustion of a mass of fuel supplied from asupply mouth 26. - By way of example, and as will be specified more fully in the course of the description, the
chamber 1 can be constituted by an incinerator furnace, a boiler supplied, for example, with coal or with tyres for motor vehicles, or other device operating by combustion in the presence of oxygen, hence excluding devices which operate by pyrolysis. - The
chamber 1 is connected via apipe 9 to a postcombustion device 2 for thermodestruction of the incondensable gases generated by combustion, which is also connected, via apipe 27, to asupply 21 of air rich in oxygen, preferably for separation of the nitrogen component, in order to maintain optimal carburation of the postcombustor, which is regulated by acontrol unit 23 and by aregulation valve 24 for modulating the air. - Preferably, the postcombustor 2 is constituted by three cylinders and a base, which may also present different shapes, and is equipped with three manifolds: a first one for inlet of
gases 43, which leads to a modulatingburner 16 with the function of bringing the postcombustor up to temperature; a second one, i.e., thepipe 9, which conveys the incondensable gases; and a third one, designated by 19, for discharge. All the components are preferably made of stainless steel coated on the inside withrefractory material 18 having the function of maintaining the internal temperature of the postcombustor itself constant. - It is understood that the postcombustor 2 may have shapes and characteristics optimized in relation to the constructional design of the plant.
- According to the invention, set along the
pipe 9, in an intermediate position between thechamber 1 and the postcombustor 2 is at least onemodule 4 for abatement, by difference in specific weight, of carbon dioxide and/or carbon monoxide present in the combustion fumes, as also of any other component having a specific weight higher than that of the incondensables, such as LPG, methane, propane, butane, or the like. - In a preferred embodiment, the
modules 4 are constituted by a conveyor 8 traversed from top down by the combustion fumes and by a current of water, which is introduced into the cylinder by apiping 12 and laps the flow of fumes, englobing and drawing along with it the carbon dioxide and possible dust, which is conveyed via adrainage pipe 11 into anunderlying tank 10 for deposit of waste water. - The circulation of the water can moreover be assisted by a recirculating
pump 17, which draws from thetank 10, which is preferably made of stainless steel and is connected to the sewage network, and delivers into thepiping 12. - With reference in particular to
FIG. 4 , described hereinafter is a preferred embodiment of themodule 4 for the abatement of CO2, CO, dust, and other components of relatively high specific weight. - The
module 4 has inside it a series of pilot tubes orducts 44, which may have different cross sections and shapes according to the requirements and have the function of directing the residue of combustion coming from thechamber 1 through thepipe 9 at inlet to themodule 4. - According to the invention, the pilot ducts are distributed in at least two
diffusers internal section 46 of themodule 4 and are separated by anempty portion 48 of thesection 46. - With this solution, the fumes coming from the
chamber 9 are distributed and traverse theducts 44 of thefirst diffuser 45, invade theempty portion 48, and are distributed again and traverse theducts 44 of thesecond diffuser 47. - During transit through the
module 4, the fumes are impinged upon by the water coming from theline 12 and sent into themodule 4 preferably throughsprayers 49. - Thanks to the thermal jump that occurs in the combustion chamber, the incondensable gases increase in volume and enter the
module 4 with a specific weight lower than the carbon dioxide, dust, carbon monoxide, and other components, which are impinged upon by the flow of water and precipitated by difference of specific weight through thedrainage pipe 11. - Advantageously, the presence in succession of a number of diffusers separated by an empty portion enables improvement of the surface of exchange between the fumes to be precipitated and the water, drastically reducing the residual content thereof in the
pipe 9 downstream of themodule 4. - In addition, according to the invention, in steady running conditions the
module 4 is traversed by the “dirty” waste water, pushed by thepump 17, with the advantage of favouring englobing of carbon dioxide, CO, and dust and their precipitation into thetank 10, as compared to the use of clear water or mains water. - Moreover provided downstream of the
module 4 along thepiping 9 is aseparator module 5 for abatement of the water vapour present in the fumes, which preferably comprises a tube-nest exchanger traversed by the fumes and by the recirculating water pushed by thepump 17, which causes condensation of the steam and falling thereof into atank 10 preferably made of stainless steel and connected to the sewage network. - In greater detail, the
separator 5 is an air/water separator constituted by two cylinders made of stainless steel or by other suitable material, inside which two nests of pipes are connected, sized so as to be self-cleaning and isolated in a fluid-tight way so as to be traversed by the exhaust fumes without coming into contact with the cooling water that laps the outer surface of the pipes themselves. - Advantageously, the treatment of separation of carbon dioxide, dust, and water vapour (and possibly nitrogen) from the fumes coming from the
combustion chamber 1 makes it possible to limit or eliminate in the postcombustion step the cooling effect otherwise caused by the fumes, and to obtain resulting gases that can be used for a further recovery of heat and of electrical energy and that after postcombustion are rendered altogether harmless. - In this connection, it is emphasized that any incineration furnace produces dioxins in the combustion chamber already at the temperature of 300° C.; then, as the temperature rises in the combustion chamber, the dioxins previously produced burn but other more resistant ones are produced, and so on until dioxins are produced that to undergo destruction require in known systems the use of postcombustors operating at above 1100° C.
- Thanks to the invention the pollutant atoms undergo previously a treatment of separation of carbon dioxide and dust and condensation of the water vapours, whilst the incondensables are pushed into the postcombustor and can be burnt at a relatively low temperature indicatively comprised between 600-700° C. or lower, with evident energetic advantage of the thermodestruction process.
- In the example described, set downstream of the module for separation of the condensate 5 a negative-
pressure device 6 is provided set along thepiping 9 with inlet of the fumes at the bottom and outlet at the top. - The negative-
pressure device 6 is preferably a extractor with variable r.p.m., or flow regulator, which determines vacuum supply of the plant, i.e., of thecombustion chamber 1, inducing a negative pressure in the upstream pipes, and a positive pressure downstream, with the further effect of aspirating the condensation gases contained in the fumes through themodules piping 9. - Moreover provided further downstream, along the
piping 9, is amodule 7 for abatement of the hydrochloric acid contained in the combustion fumes that are by now deprived of the condensation component and are to go on to the postcombustor. - Preferably, the
module 7 is constituted by acylindrical container 7, inside which a mixture of water and bicarbonate, soda or the like is present, preferably supplied automatically for neutralizing the acids contained in the incondensables. Thecylinder 7 is traversed from bottom to top by the fumes coming from thepiping 9 and comprises apump 20 for circulation of the bicarbonate mixture taken from adeposit 19, which draws in from thetank 10, the bicarbonate mixture being introduced via a piping 30 into thepipe 9 at inlet to thecylinder 7. In addition, also themodule 7 is traversed by the recirculating water coming from the piping 30 and poured back into thetank 10 via thedrainage pipe 11. - It is understood that the number and sizing of the
modules - In operation, the fumes introduced by the
pipe 9 traverse the bicarbonate mixture present in thecylinder 7 and undergo abatement of the acids, which are poured, by now neutralized, into thetank 10 through the stretch ofdrainage pipe 11, reaching the top stretch of thepipe 9 without any acid content. - At the same time the
pump 20 carries out circulation of the bicarbonate mixture by drawing from thedeposit 29 and from thetank 10 via apiping 49. - Advantageously, according to the invention, the devices for abatement of the
carbon dioxide 4,water vapour 5, andhydrochloric acid 7 can be assembled in a replaceable and modular way along saidpipe 9 on the basis of the application and size of the plant and the type of fuel introduced into thechamber 1. - At outlet from the
module 7, thepipe 9 conveys the residual incondensable gases into the postcombustor 2, to carry out thermodestruction thereof, already at temperatures that range from 600 to 700° C. - Once thermodestruction of the fumes has been carried out, the postcombustor 2 finally discharges, via a
pipe 19, the residual fumes, which are by now free from any pollutant content. - Advantageously, the
connection pipe 9, before conveying the component of incondensable gases coming from thecombustion chamber 1 into the postcombustor, passes through all theseparator devices - Once again with reference to the figures, a plant according to the invention can comprise a
control unit 23 for governing avalve 24 for regulation of the volume of oxygen-enriched air that is to reach the postcombustor 2 on the basis of the values of oxygen content detected by aprobe 25 set in the proximity of the outlet of the combustion fumes from thechamber 1. - With this solution it is advantageously possible to adapt automatically the temperature reached in the postcombustor, and hence the level necessary for thermodestruction of the pollutants, on the basis of the type of fuel introduced, even if the latter varies over time as occurs in the case of urban solid waste. In this context, it is specified that the
combustion chamber 1 may consequently be constituted by a furnace for incineration of solid and/or liquid toxic-noxious waste, for example, chemical/pharmaceutical waste, or else again by a boiler for combustion of coal or tyres, or else a converter furnace supplied with liquid fossils, or a furnace for incineration and gasification of urban solid waste (USW). - With reference to
FIG. 2 , described hereinafter is an embodiment of the invention comprising an energy-recovery assembly 31 set between saidcombustion chamber 1 and the module for abatement ofcarbon dioxide 4. - In this case, the
combustion chamber 1 is preferably constituted by a combustion chamber of a gasification furnace 41 for the production of syngases, which does not require supply of air for the combustion because it works in defect of air, but uses only a limited amount of carbon dioxide that serves for transfer of the gases obtained from thefurnace 1 to theassembly 31, without, however, burning the gas produced. - In the preferred embodiment illustrated, the
assembly 31 comprises apostcombustor 13, which comprises amodular burner 16 and is supplied via apipe 50 by the combustion fumes of thechamber 1 and which, in turn, supplies asteam generator 3 provided with anoutlet 32 for the steam produced that is to be sent on to aturbine 15, preferably through avalve 38, and with anoutlet 40 for the residual fumes that are to be sent on to the device for abatement ofcarbon dioxide 4. - In this embodiment a
second control unit 33 may moreover be provided for governing avalve 34 for regulation of the volume of oxygen-enriched air that comes from thesupply 21 and that is to be sent to the postcombustor 2 and/or 13, which can be modified on the basis of the values of oxygen content detected by theprobe 25 set at the outlet from thechamber 1 and by aprobe 35 set, instead, in the proximity of theoutlet 40 of the combustion fumes from thesteam generator 3. - Preferably, a
second steam generator 14 can moreover be provided, supplied by the postcombustor 2 and provided with anoutlet 36 for the steam produced that is to be sent on to aturbine 15, preferably through avalve 38, and moreover connected to theoutlet 19 of the pollutant-free exhaust fumes. - According to the invention moreover envisaged is the use of a
probe 37 for measuring the contents of the fumes at theexhaust 19, which is connected to thecontrol unit 23. - Advantageously, reading of the characteristics of the gases emitted by the plant through the
exhaust 19 enables optimization of the combustion temperature that can be obtained in thechamber 1, in the postcombustor 2, and in thepostcombustor 13. - By way of example provided hereinafter are the results of two different tests conducted by means of sampling of the fumes produced by a plant made in compliance with the plant of
FIG. 1 , by measuring the contents of the fumes detected at theoutlet 19. - The samplings carried out comprised:
-
- determination of the parameters of the combustion fumes using a MADUR “GA-40 PLUS” analyser;
- sampling for determination of dust and recovery of the condensate with subsequent determination of T.O.C. (total organic carbon) in the condensate recovered in the
tank 10 and of some metals once again in the condensate and on a filter after it was treated with nitric acid; the determination of the metals was carried out by means of atomic-absorption spectrophotometry; - sampling for determination of the incondensable volatile organic substances after prior absorption of the flow sampled on a vial of activated carbon, extraction with CS2, and subsequent gaschromatographic determination;
- sampling for determination of acids (HCl and HF) after prior bubbling of the flow drawn into a basic solution; the subsequent determination of the chloride and fluoride ions was performed by means of ion chromatography. The samples were taken at the
outlet 19 of the combustion fumes from thepostburner 13.
- During sampling the plant was supplied with offcuts of finished leather, shearings and bags for containing raw leather, shredded plastic drums, urban solid waste (USW), empty containers of chemical products, PVC, chrome-leather shavings, and drums made of rubber.
- In the following tables the values of concentration given in the second column are normalized at the temperature of 273 K and at the pressure of 101.3 kPa, whilst in the third column the same values of concentration are given referred, however, to an oxygen content of 11% (as indicated in the attachments of the Ministerial Decree dated Feb. 5, 1998 “Determination of the limit values and prescriptions for the emissions into the atmosphere of the activities of recovery of energy from non-dangerous waste”—“Determinazione dei valori limite e prescrizioni per le emissioni in atmosfera delle attivita di recupero energia dai rifiuti non pericolosi” and in the attachment of the Italian Ministerial Decree No. 124 dated Feb. 25, 2000.
-
Temperature 217° C. O2 8.7% CO2 9.7% -
Value ref. 11% Limit values Concentration O2 Daily Half-time Pollutant mg/Nm3 mg/Nm3 mg/Nm3 mg/Nm3 CO 22 18 50 100 NOx 165 127 200 400 SOx 30 24 50 200 - Condensate recovered=32 ml
-
Start of samplings End of samplings Time: 11.55 Time: 24.00 -
Value ref. 11% Limit values Concentration O2 Daily Half-time Pollutant mg/Nm3 mg/Nm3 mg/Nm3 mg/Nm3 DUST 1.8 1.5 10 30 T.O.C. 1.9 1.5 10 20 -
Value ref. Concentration 11% O2 Limit Metal mg/Nm3 mg/Nm3 mg/Nm3 Chromium 0.348 0.246 * Copper 0.030 0.024 * Cadmium 0.058 0.047 0.05 Led 0.021 0.017 * * = 0.5 mg/Nm3 as average value of the sum of the concentrations of ten metals (Sb, As, Pb, Cr, Co, Cu, Mn, Ni, V, Sn). -
-
Value ref. Limit values Concentration 11% O2 Daily Half-time mg/Nm3 mg/Nm3 mg/Nm3 mg/Nm3 HCl 0.022 0.018 10 60 HF N.R. N.R. 1 4 - The following volatile organic substances were identified, all with concentrations of much lower than 1 mg/Nm3:
-
Butane Heptane Butyl alcohol Isopropyl alcohol Trichloroethylene Ethylbenzene Ethyl acetate Methylcyclohexane Xyloles Thiourea Toluol - A series of analyses were conducted for sampling the combustion fumes for determination of polychlorodibenzodioxins (PCDDs), polychlorodibenzofurans (PCDFs), and polycyclic aromatic hydrocarbons (PAHs).
- The samples were taken at outlet of the combustion fumes from the postcombustor.
- The samplings carried out comprised:
-
- determination of the parameters of the combustion fumes with MADUR “GA-40 PLUS” analyser;
- determination of PCDDs, PCDFs, and PAHs according to the method UNICHIM No. 825/1988 and subsequent modifications as indicated in the attachments of the Italian Ministerial Decree dated Feb. 25, 2000;
- in particular a sample was taken of the aeriform in isokinetic conditions (method UNICHIM 494), by inserting downstream of the sampling and dust-collection probe a coolant for recovery of the condensate and at outlet from the condenser two absorption cartridges containing synthetic resins;
- at the end of sampling both the probe and the condenser were accurately washed with acetone; the washings were then added to the solvent used for extraction of the micropollutants from the condensate;
- the determination of the micropollutants was carried out on the particulate material, on the condensate, and on the adsorbent material after prior “extraction” with toluene;
- all the extracts combined were divided into two aliquots, one for determination of the PAHs and one for determination of the PCDDs and of the PCDFs, after prior purification and separation from the PCBs by means of mass-spectrometry gaschromatography;
- the results of the analyses conducted were normalized at the temperature of 273 K, at the pressure of 101.3 kPa, and referred to a volume of dry gas.
- During sampling, the plant was supplied with urban solid waste (USW), offcuts of “finished” leather, shearings and bags for containing raw leather, shredded plastic drums, other empty containers of chemical products, chrome-leather shavings, and other waste of plastic material coming from various processing operations.
- In addition, the
postcombustor 13 was programmed in such a way that the gases produced by incineration of the waste were brought, after the last introduction of combustion air and before expulsion into the atmosphere, at a temperature of at least 950° C. - Given in the tables below are the concentrations of the pollutants found and referred to an oxygen content of 11%.
-
-
Temperature 217° C. O2 8.5% CO2 9.9% -
Limit values Pollutant Concentration Daily Half- time CO 25 mg/ Nm 350 mg/Nm3 100 mg/Nm3 NOx 179 mg/Nm3 200 mg/Nm3 400 mg/Nm3 SOx 19 mg/ Nm 350 mg/Nm3 200 mg/Nm3 -
-
Effective duration of Start of sampling End of sampling sampling Time: 16.30 Time: 04.30 720 min Suction flow Volume sampled (l) Volume sampled (273K 101.3 kPa) 11.1 l/min 8340.5 7906.1 -
Limit value Pollutant Concentration Concentration PCDD + PCDF <0.06 ng/Nm3 0.1 ng/Nm3 (*) PAHs 0.009 mg/Nm3 0.01 mg/Nm3 (*) (*) as mean value detected for a sampling period of 8 hours and referred to 11% of O2 in the gaseous effluent. - The invention achieves important advantages.
- The system is pre-arranged for modular solutions, i.e., for providing both in medium-sized and in large-size plants a series of modular and conversion furnaces that can be used also in alternating phases.
- With the system in question syngas is produced with any waste, for example through a coaxial furnace with programmed and continuous supply through which a high level of functionality and safety is achieved. This result is possible not only because the combustion furnace is a variable-geometry furnace but also because it is supplied with oxygen-enriched air, produced by the
device 21, for example, a device that separates nitrogen from the supply air of the burners, furnaces, heat accelerators, and postcombustors. With this solution it is hence possible to provide progressively smaller and more compact plants, but ones having a functionality and efficiency of thermodestruction of pollutants that is increasingly high. In fact, if it is considered that the nitrogen contained in the air is approximately 70% and if 40% is extracted, in proportion to the size it is possible to build systems of dimension that are 30%-40% smaller. - In addition, since the amount of nitrogen that is introduced into the chambers for combustion of the waste and into the heat accelerators is normally 30%-40% higher, thanks to the invention the extinguishing effect is prevented and hence there is obtained a saving for ignition of the furnaces and of the heat accelerators, which require an amount of energy that is 30-40% less to reach steady running conditions.
- Thanks to the possibility of adjusting the supply of the oxygen-enriched air and to the use of the
adjustable aspirator 6, the plant constitutes a true means of thermal destruction of waste and fumes with continuos variable adjustment at a controlled temperature. - In addition, the plant is suited for obtaining easily the conversion of electric power stations into fossil-carbon power stations.
- Furthermore, with the gases that are produced it is possible to supply cogeneration or produce LPG, along with abatement of the pollutants into the atmosphere.
- In addition, thanks to the invention destruction of the incondensables produced by combustion and recovery of the potential energy contained therein in order to produce electrical energy are obtained.
- The system forming the subject of the present invention enables in fact recovery both of the potential energy of the waste introduced into the combustion chamber and of the resulting incondensables, which form an excellent syngas with a calorific power higher than 516 000 kcal.
- At the same time, said incondensables, by passing through the postcombustor already at temperatures of 600-700° C. are destroyed, as likewise the pollutants contained in the carbon atoms, etc., in such a way that, once freed into the environment, they are altogether harmless and breathable.
- The system thus conceived is suitable for evident industrial application; it may likewise undergo numerous modifications and variations, all of which fall within the scope of the inventive idea; all the items may moreover be replaced by technically equivalent elements.
Claims (25)
1. A combustion plant, comprising:
a combustion chamber for combustion of a mass of fuel;
a postcombustion device for thermodestruction of the incondensable gases generated by combustion in the chamber;
a pipe for transporting the combustion fumes from said chamber into said postcombustor;
a separation device for separation of the incondensable gases from the combustion fumes that are generated by the chamber and that are to reach the postcombustor, said separation device being a device for abatement, by difference of specific weight, of at least the carbon dioxide contained in the combustion fumes.
2. A plant according to claim 1 , wherein said device for abatement of carbon dioxide is a device for abatement of the dust and of the carbon oxide and of the heavy components contained in the combustion fumes that are to reach the postcombustor.
3. A plant according to claim 1 , wherein said device for abatement of carbon dioxide comprises at least one conveyor traversed by the flow of said fumes and by a current of water that laps the flow of the fumes to cause precipitation of the carbon dioxide into a drainage outlet.
4. A plant according to claim 3 , wherein said conveyor comprises at least two diffusers set in the internal section of the conveyor traversed in succession by the fumes and by said flow of water and separated by an empty portion of the internal section.
5. A plant according to claim 1 , further comprising a device for abatement of the water vapor contained in the combustion fumes that are to reach the postcombustor.
6. A plant according to claim 1 , further comprising a device for abatement of the hydrochloric-acid content in the combustion fumes that are to reach the postcombustor.
7. A plant according to claim 1 , further comprising a negative-pressure device set in an intermediate position between said chamber and said postcombustor to induce a vacuum supply of the chamber.
8. A plant according to claim 7 , wherein said device for abatement of the hydrochloric acid comprises a cylindrical container traversed by the piping and a pump for circulation of a bicarbonate mixture in the cylinder.
9. A plant according to claim 5 , wherein said device for abatement of the water vapor is constituted by a tube-nest condenser.
10. A plant according to claim 7 , wherein said negative-pressure device is constituted by an adjustable aspirator.
11. A plant according to claim 1 , further comprising a pump for recirculation of waste water from a collection tank at least into said separation device.
12. A plant according to claim 1 , further comprising devices for abatement of carbon dioxide, water vapor, and hydrochloric acid assembled in a replaceable and modular way along said pipe.
13. A plant according to claim 1 , wherein said combustion chamber is a furnace for incineration of toxic-noxious solid waste.
14. A plant according to claim 1 , wherein said combustion chamber is a furnace for incineration of toxic-noxious liquid waste.
15. A plant according to claim 1 , further comprising an adjustable supply of oxygen-enriched air that is to reach said postcombustor.
16. A plant according to claim 15 , further comprising a control unit for governing a valve for regulation of the volume of oxygen-enriched air that is to reach the postcombustor on the basis of the values of oxygen content detected by a probe set in the proximity of the outlet of the combustion fumes from the chamber.
17. A plant according to claim 1 , further comprising an energy-recovery assembly set between said combustion chamber and said device for abatement of carbon dioxide.
18. A plant according to claim 17 , wherein said chamber is the combustion chamber of a gasification furnace and said assembly comprises a heat-accelerator burner, which is supplied by the gases produced by the furnace and in turn supplies a steam generator provided with an outlet for the steam produced that is to reach a turbine and with an outlet for the residual fumes that are to reach the device for abatement of carbon dioxide.
19. A plant according to claim 17 , further comprising a control unit for governing a valve for regulation of the volume of oxygen-enriched air that is to reach the burner on the basis of the values of oxygen content detected by a probe for the combustion fumes at outlet from the chamber and by a probe set in the proximity of the outlet of the residual combustion fumes at outlet from the steam generator.
20. A plant according to claim 17 , further comprising a second steam generator supplied by said postcombustor and provided with an outlet for the steam produced that is to reach a turbine and an outlet of the exhaust fumes free from pollutants.
21. A plant according to claim 17 , further comprising a probe for measuring the contents of the fumes at the exhaust outlet, which is connected to said control unit.
22. A plant according to claim 17 , further comprising at least one valve for opening/closing the flow of steam passing between said steam generators and said turbine.
23. A plant according to claim 17 , wherein said combustion chamber is a boiler for combustion of coal or tyres.
24. A plant according to claim 17 , wherein said combustion chamber is a converter furnace supplied with liquid fossils.
25. A plant according to claim 17 , wherein said combustion chamber is a furnace for incineration and gasification of urban solid waste (USW), and/or toxic-noxious waste.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ITPCT/IT2008/000521 | 2008-07-31 | ||
IT2008000521 | 2008-07-31 | ||
PCT/IB2009/006380 WO2010013117A1 (en) | 2008-07-31 | 2009-07-28 | Combustion plant with abatement of pollutants |
Publications (1)
Publication Number | Publication Date |
---|---|
US20110131990A1 true US20110131990A1 (en) | 2011-06-09 |
Family
ID=40503887
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/056,706 Abandoned US20110131990A1 (en) | 2008-07-31 | 2009-07-28 | Combustion plant with abatement of pollutants |
Country Status (3)
Country | Link |
---|---|
US (1) | US20110131990A1 (en) |
EP (1) | EP2315972A1 (en) |
WO (1) | WO2010013117A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140348717A1 (en) * | 2013-05-24 | 2014-11-27 | Ebara Corporation | Vacuum pump with abatement function |
CN108593809A (en) * | 2018-06-29 | 2018-09-28 | 莱茵技术(上海)有限公司 | A kind of detection device and method burned for organic matter |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104597754A (en) * | 2015-01-04 | 2015-05-06 | 北京华清燃气轮机与煤气化联合循环工程技术有限公司 | Overall efficiency optimization control method of IGCC (integrated coal gasification combined cycle) power station with hot end component as core |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4599953A (en) * | 1985-07-08 | 1986-07-15 | Gould William A | Garbage to hydrocarbon fuel conversion system |
US5050508A (en) * | 1990-10-09 | 1991-09-24 | Hcr | System for the incineration of refuse and the treatment of the incineration exhaust gasses |
US5222446A (en) * | 1991-05-29 | 1993-06-29 | Edwards A Glen | Non-polluting incinerator |
US5607654A (en) * | 1991-06-10 | 1997-03-04 | Beco Engineering Company | Method for minimizing environmental release of toxic compounds in the incineration of wastes |
US20100021362A1 (en) * | 2007-02-20 | 2010-01-28 | Hunwick Richard J | System, apparatus and method for carbon dioxide sequestration |
US7819070B2 (en) * | 2005-07-15 | 2010-10-26 | Jc Enviro Enterprises Corp. | Method and apparatus for generating combustible synthesis gas |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3153091B2 (en) * | 1994-03-10 | 2001-04-03 | 株式会社荏原製作所 | Waste treatment method and gasification and melting and combustion equipment |
DE19709383A1 (en) * | 1997-03-07 | 1998-09-17 | Sachsenholz Ag | Process for energetically utilising biomass |
KR100689788B1 (en) * | 2005-07-19 | 2007-03-09 | (주)한국환경기술 | An incineration method of waste and its device, in that waste gas from incinerator is recycled, mixed with oxygen and applied for burning |
WO2007024687A2 (en) * | 2005-08-23 | 2007-03-01 | Edmondson Jerry M | Pyrolytic resource recovery system |
US7744663B2 (en) * | 2006-02-16 | 2010-06-29 | General Electric Company | Methods and systems for advanced gasifier solids removal |
-
2009
- 2009-07-28 EP EP09802578A patent/EP2315972A1/en not_active Withdrawn
- 2009-07-28 WO PCT/IB2009/006380 patent/WO2010013117A1/en active Application Filing
- 2009-07-28 US US13/056,706 patent/US20110131990A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4599953A (en) * | 1985-07-08 | 1986-07-15 | Gould William A | Garbage to hydrocarbon fuel conversion system |
US5050508A (en) * | 1990-10-09 | 1991-09-24 | Hcr | System for the incineration of refuse and the treatment of the incineration exhaust gasses |
US5222446A (en) * | 1991-05-29 | 1993-06-29 | Edwards A Glen | Non-polluting incinerator |
US5607654A (en) * | 1991-06-10 | 1997-03-04 | Beco Engineering Company | Method for minimizing environmental release of toxic compounds in the incineration of wastes |
US7819070B2 (en) * | 2005-07-15 | 2010-10-26 | Jc Enviro Enterprises Corp. | Method and apparatus for generating combustible synthesis gas |
US20100021362A1 (en) * | 2007-02-20 | 2010-01-28 | Hunwick Richard J | System, apparatus and method for carbon dioxide sequestration |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140348717A1 (en) * | 2013-05-24 | 2014-11-27 | Ebara Corporation | Vacuum pump with abatement function |
US10143964B2 (en) * | 2013-05-24 | 2018-12-04 | Ebara Corporation | Vacuum pump with abatement function |
CN108593809A (en) * | 2018-06-29 | 2018-09-28 | 莱茵技术(上海)有限公司 | A kind of detection device and method burned for organic matter |
Also Published As
Publication number | Publication date |
---|---|
WO2010013117A1 (en) | 2010-02-04 |
EP2315972A1 (en) | 2011-05-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN206045771U (en) | Organic exhaust gas total system | |
Su et al. | Evaluation of a flue gas cleaning system of a circulating fluidized bed incineration power plant by the analysis of pollutant emissions | |
CN109469903B (en) | Incineration treatment method for industrial solid waste | |
CN105757688A (en) | Method and system for treating VOCs gas in sewage treatment plant | |
KR20030067241A (en) | Method and Apparatus for excluding dioxin and fly ash using high temperature plasma | |
US6952997B2 (en) | Incineration process using high oxygen concentrations | |
CN108151023A (en) | Industrial waste high temperature incineration gas cleaning treatment process | |
CN111306549A (en) | Green and efficient rotary kiln incineration treatment method for hazardous wastes based on oxygen-enriched air supply of secondary combustion chamber | |
CN109945211B (en) | Burning treatment method and system for semi-coke pyrolysis waste gas and waste liquid | |
Wang et al. | Formation and removal of PCDD/Fs in a municipal waste incinerator during different operating periods | |
CN102317687A (en) | Be used to handle the method and apparatus of solid waste | |
US20110131990A1 (en) | Combustion plant with abatement of pollutants | |
CN105627326B (en) | Incineration treatment of garbage unit | |
CN209196850U (en) | Refuse disposal installation | |
CN104588399B (en) | A kind of device of garbage disposal cogeneration | |
CN111197754A (en) | Green high-efficient hazardous waste rotary kiln incineration processing system based on oxygen-enriched air supply of secondary combustion chamber | |
CN105698177A (en) | Incineration treatment method for wastes | |
CN213433606U (en) | Coke and asphalt smoke tail gas treatment device | |
CN213746746U (en) | Harmless treatment equipment for hazardous waste | |
CN204412746U (en) | A kind of device of garbage disposal cogeneration | |
CN101307905B (en) | Carbon product calcining furnace flue gas cleaning treatment process | |
CN211902914U (en) | Green high-efficient hazardous waste rotary kiln incineration processing system based on oxygen-enriched air supply of secondary combustion chamber | |
Carabin et al. | Two-stage plasma gasification of waste | |
CN205402735U (en) | Waste incineration unit | |
CN214223104U (en) | Magnetization decomposition device for medical waste treatment |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |