FR2837495A1 - MODULAR, DEMOUNTABLE, TRANSPORTABLE PLANT FOR THERMOLYSIS TREATMENT AND FOR ENERGY RECOVERY OF WASTE - Google Patents

Abstract

- Removable, transportable modular structure comprising essentially (Figure 1) - A module (i) for loading and delivering the waste to be treated (1) - A module (5) for drying the waste (5) - A module (2) reactor thermal dissociation under reduced pressure and at high temperature - A thermolysis gas suction module (3) - A module (4) for upgrading the energy recovered in the organic fraction of the treated waste - A module (8) of smoke treatment. This installation by combining the operating parameters of the process (residence time; temperature; depression) implemented by this installation and in the combustion-free treatment mode of the solid residues resulting from thermolysis, makes it possible to trap heavy metals in the part. carbonaceous solid residues resulting from thermolysis, mainly during the treatment of sewage sludge.

Description

Claims 1 to 23 around said core to form said sheath.

  MODULAR 'REMOVABLE, TRANSPORTABLE INSTALLATION FOR THE

  THERMOLYSIS TREATMENT AND FOR RECOVERY

WASTE ENERGY

  Technical field / The invention relates to a modular installation, removable and transportable by road preferably or by any other means of transport, for treatment by thermolysis, simultaneously for the energy recovery of waste containing a fraction

  organic, as well as a smoke treatment, integrated into the process.

  Prior techniques The treatment of waste containing an organic fraction is well known, in particular for the treatment of waste as diverse as automobile grinding residue (RBA), hospital waste also called care waste, used tires, green waste resulting from biomass, urban or household waste, meat-and-bone meal, sewage treatment plant sludge and sludge from various petroleum products. The treatment of this waste is becoming more and more worrying as a result of the ever-increasing quantities to be treated as well as the increase in the cost of these treatments. The thermal dissociation of waste under reduced pressure and at high temperature of matter containing an organic fraction is well known (see notament document

  US-A- 4,077,868, 4,833,021 and CA-A- 1,163,595).

  Essentially, a thermal pressure dissociation installation of waste containing an organic fraction essentially comprises: - a unit for loading and supplying the waste to be treated, - a thermal dissociation reactor under reduced pressure and at high temperature between 400 and 1000 C, especially around 500 C, under pressure between 500 and 40,000 Pascals below atmospheric pressure. In patent No. 94 12574 of 10/17/1994, the applicant described a typical installation in question, in which between the supply means and the resector; there are two chambers, placed in parallel, each connected to the means for supplying the reactor, thus allowing loading at atmospheric pressure in one of the two chambers while the other discharges at reduced pressure into the reactor. This discontinuous / continuous installation well suited to the treatment of large quantities, however has the disadvantage of requiring a significant investment by the fact

  to put two rooms which can be used for drying.

  Furthermore, the production of oils by contamination during treatment is on the

  practical plan difficult to manage industrially.

  The invention overcomes these drawbacks. It targets an installation for the thermolysis treatment of waste and for the energy recovery of this waste, which is well suited to the treatment of a wide variety of waste, in small and medium capacities, with a good ratio between investment and operation. It relates more particularly to an installation of the type in question which is reliable and robust and whose

  operating conditions scrupulously respect the environment.

  The invention refers to patent No. 97 05 426 of 04/25/1997 which describes an installation

  for thermolysis treatment and for energy recovery from waste.

  The invention is a new technical development of patent no. 97 05 426 of 25104/1997, suitable for dry, semi-humid or wet waste occurring under

  form of sludge, flour or products of small particle size.

  It relates to an installation of the modular type, which can be dismantled, preferably transportable by road or any other means of transport, comprising the stages of the process described in patent No. 97 05 426 plus a smoke treatment. In this installation, the energy produced during the treatment is recovered to operate the installation in part and the part itself and possibly part of the unit capable of

produce this waste.

  This modular type installation makes it possible to integrate all the stages of the thermolysis process and of the smoke treatment in the set of modules which can be easily dismantled and transported by road as a means of preference or any other means of transport. The establishment and arrangement of these different modules advantageously makes it possible, once assembled, to simplify certain steps of the process.

Brief description of the invention

  The invention relates to an installation for the thermolysis treatment of waste comprising an organic fraction and having a controlled particle size and simultaneously for the recovery of this waste, installation of the type essentially comprising: A / - a module (1) for loading and supply of the waste to be treated, - a module (5) for drying the waste, - a module (2) for thermal dissociation under reduced pressure and at high temperature or for thermolysis, - a module (3) for suction of thermolysis, - a module (4) for recovering the energy recovered in the organic fraction of the treated waste, - a module (8) for smoke treatment, This installation by combining the operating parameters of the process (residence time, temperature, depression) implemented by this installation and in a treatment mode without combustion of the solid residues resulting from thermolysis, makes it possible to trap heavy metals in the carbon portion of the solid residues from the

  thermolysis, mainly during the treatment of sludge from wastewater treatment plants.

  To allow its transport and its easy installation, the installation, according to the invention, consists essentially of: B / A modular structure of which each module (1 to 8) comprises the means of

  realization of one of the phases of the treatment targeted by the installation of the invention.

  This structure being arranged to be transportable by road as a means of preference or any other means of transport and the connecting members by

  quick connections to upstream and / or downstream modules.

  In other words, the invention consists in having, in a compact and transportable modular structure, not only the equipment necessary to heat the waste having a particle size and a controlled dryness under conditions capable of dissociating this waste. The dissociation is essentially done in two phases, respectively gaseous and solid and this in quasi-absence of oxygen, but under

  reduced pressure, even under a gaseous atmosphere.

  The invention also consists in also having the equipment necessary to recover the gaseous and solid phases in order to recover them by producing energy in a combustion chamber intended to heat the steam which in turn feeds,

  a device for pre-drying the waste entering upstream of the reactor.

  Preferably, this installation according to the invention further comprises the equipment (8) necessary for the treatment and purification of the fumes extracted from the installation, at

  in order to comply with the standards for atmospheric discharge in force.

  In the installation which is the subject of the present invention, as in the aforementioned installation known from document FR 97 05 426, thermolysis, also known as "pyroiysis", is carried out at a temperature between 400 and 1000 ° C., in particular at around 500 C, with a pressure in the reactor from 500 to 40,000 Pascals, preferably 10,000 Pascals below atmospheric pressure. The residence time of the waste in the reactor is of the order of several tens of minutes, for

  example of the order of forty minutes.

  In this installation, like the one already mentioned above, the waste to be treated can be prepared to have a particle size, a dryness and a consistency

  controlled, even homogeneous physics.

  Similarly, they can undergo a preliminary drying intended to lower the content of this waste in water. This heating carried out in an appropriate enclosure can, depending on their nature, be carried out in two ways; namely direct or indirect. In direct drying, the mass of waste is heated by a circulation of hot air or recycled steam from the generator characteristic of the invention or recycled hot air

from the combustion chamber.

  This pre-drying method is particularly suitable for waste with a low volatile solid fraction (dust). When treating sludge from sewage treatment plants, it is preferable to carry out indirect heating, i.e. to heat the enclosure from the outside, while ensuring a certain mixing intended for

  stir the product to increase the contact surface with air.

  According to a particular embodiment of the invention, the assemblable and dismountable modules are arranged so as to ensure: - Gravity recycling of the waste being dried until the dried product thus obtained has sufficient dryness to be treated in the thermolysis resector (2), - The routing of steams and drying condensates by gravity duct (35) towards the combustion chamber (313 to be burned there, - The routing of the condensates of the steam supplying the dryer (13), by duct

  gravitational towards the steam generator (34).

  Brief description of the attached figures

  Fig 1 is a side elevation view of this installation; Fig 2 shows a side view in elevation, the module comprising the waste reception hopper and the means of conveying them to the next drying module; Fig 3 is a side elevational view showing the waste drying module or dryer; Fig 4 is a side elevational view showing the module comprising a buffer hopper between the dryer and the thermolysis resector; Fig 5 shows a side view in elevation, the module comprising the thermolysis reactor with its entry airlock, its exit airlock and associated conveying means; Fig 6 shows a side view in elevation, the module comprising the means for extracting and transferring gases from the reactor to the combustion chamber Fig 7 is a side view in elevation showing an empty module interposed between d '' other modules to facilitate access; Fig 8 shows a side view in elevation, the combustion chamber of the thermolysis gases and the fumes as well as the steam generator;

  Fig 9 shows a side elevation view of the smoke purification module.

  Manner of Carrying Out the Invention Referring to FIG. 1, the arrangement of the modules from (1) to (8) in the installation is represented in accordance with the invention, namely: - a lower level: module of (1) to (4) - a higher level: module from (5) to (8) As shown in Figure 2, the module (1) includes the means for receiving the waste to be treated by the hopper (9) and pumping (10) and shipping to

the pipe dryer (11).

  S As shown in Figure 1, Figure 3 and Figure 8, the module (5) includes the waste drying means. The waste arrives through the piping (11), returns through the rotary inlet orifice (12) placed in the center of the rotary dryer (13). The waste advances into this dryer and is then discharged from the dryer through the outlet orifice (14). The condensates and the drying vapors are sent by natural slope by a

  piping (15) to the combustion chamber (31).

  As shown in particular in FIG. 1, FIG. 4 and FIG. 5, the module (6) comprises the means for buffer storage of the dried waste. It consists of a dry waste inlet (16) supplied by the dryer waste outlet (14) of a buffer hopper (17) emptied by an extractor (18) supplying the

réacteurdethermolyse (19).

  As shown notably in FIG. 1, FIG. 4, FIG. 5 and FIG. 6, the module (2) comprises the thermolysis means composed of an arrival of dry waste by a conduit (20) connecting the buffer hopper and the entry airlock (21). The entry airlock is emptied by an archimedean screw (22) supplying the thermolysis reactor (19) from above. The thermolysis reactor is drained from below by an archimedean screw (23) supplying an exit airlock (24). The output sound is emptied by the archimedes screws (25) and (26) which convey the solid residues from the thermoiyse to a storage in big beg or container to be sent to a landfill. The gases from the thermolysis of waste leave the reactor (19) via a pipe (27) located at the top of the thermolysis reactor to be directed to the suction and extraction group of the

thermolysis gases (28).

  As shown in particular in FIG. 1, FIG. 6 and FIG. 8, the module (3) comprises the means for extracting and pumping the organic fraction of the waste in the form of gases. Their extraction and pumping is done from the top of the thermolysis reactor by the conduits (27) and (29) and the gas suction and extraction group (28) which sends them through the conduit (30) into the room of

combustion (31).

  As shown in particular in FIG. 1, FIG. 3, FIG. 8 and FIG. 9, the module (4) comprises the means for the combustion of thermolysis gases, steams and drying condensates as well as the production of steam for ensure drying. The thermolysis gases arrive in the combustion chamber (31) through the conduit (30) to be burned there. The steams and condensates for drying the waste come from

  dryer (13) through a conduit (15) to be burned in the combustion chamber (31).

  S The combustion gases are pumped by a smoke extractor vacuum cleaner (32) and routed through a conduit (33) in the steam generator (34) to recover the energy contained in the combustion gas and produce steam . The steam produced by the steam generator (34) is conveyed to the waste dryer (13) through the conduit (35). After energy recovery by the steam generator (34), the cooled gases leave via the conduit (36) in the treatment module

fumes (8).

  As shown in particular in FIG. 1, FIG. 8 and FIG. 9, the module (8) comprises the means for treating the fumes. The smoke treatment is composed of a neutral isation reactor (37) where the reagents are dosed and injected in order to neutralize the harmful particles of these fumes, a bag or ceramic filter (38) with back pressure cleaning or ceramic operating at dry. an extraction (41) of the filtration purification residues with their evacuation towards the outside, a vacuum cleaner / extractor (32) of the fumes towards a chimney (39) for discharging the purified gases, a smoke control system

  rejected continuously checking compliance with standards for atmospheric emissions (40).

8 2837495

Claims (12)

claims   1. Installation for the thermolysis treatment of waste comprising an organic fraction and having a controlled particle size and7 simultaneously, for the recovery of this waste comprising essentially: - a module (1) for loading and supplying the waste to be treated, - a waste drying module (5), - a module (2) for thermal dissociation under reduced pressure and at high temperature or for thermolysis, - a module (3) for suction of thermolysis gases, - a module (4 ) recovery of the energy recovered from the organic fraction of the treated waste,   - a smoke treatment module (.8).   2. Installation according to claim 1 characterized in that it further comprises the equipment necessary for the treatment and purification of the fumes extra ites   1'7nstallation, in order to respect the standards of rejection to the atmosphere in force.   3. Installation according to claim 1 or claim 2 characterized in that it comprises means (5) for treating the waste so that it has sufficient dryness.   4. Instatlation according to the set of preceding claims characterized in that   that the co.mp.makes.a steam generator (4) from which steam is sent. drying module (5).   5. Installation according to any one of the preceding claims, characterized in   that the assemblable and dismountable modules are arranged so as to ensure: - a gravity recycling of the waste during drying until the dried product thus obtained has sufficient dryness to be processed in the thermolysis resector (2) , The routing of the steams and drying condensates by gravity duct (15) towards the combustion chamber (4) to be burned there, 9 2837495   - Condensate-steam supply to the dryer (5), by conduit   gravity to the steam generator (4).   6. Installation according to any one of the preceding claims, characterized in   that the drying module (5) is disposed at the upper level of the installation thus allowing the recycling by gravity of the waste until the product obtained   obtain a suffi cient sicci t for treatment by thermolysis.   AT 7. Installation according to any one of the preceding claims, characterized in   what means to recover the gaseous fraction of the waste that is collected   by the extraction module (3) are arranged in the upper part of the reactor (2).   8. Installation according to any one d.es reve.ndications previous carac.té.risée in that the means for recovering the solid fraction of the waste are arranged in   lower part of the reactor (2).   9. The installation according to one of the preceding claims, characterized in   A ryens are provided in the upper part of the dryer (13) to convey the steams and drying condensates, by natural slope flow, to the combustion chamber (31).   10. Installation according to any one of the preceding claims, characterized in   that means are provided for conveying the gases from the combustion chamber (31) and the steam produced by the steam generator arranged at the level   bottom of the installation supplying the drying module (5) of the incoming waste.   11. Installation according to any one of the preceding claims, characterized in   what it includes a smoke treatment and purification module (8).   12. Installation according to any one of the preceding claims, characterized in   what it is characterized in that the airlocks are chosen from the group made up