The object of this invention is continuously operating pyrolysis equipment that composes at least of a feeding apparatus to feed raw material into the reactor, a reactor to produce the pyrolysis products, a heating system to produce the necessary heat energy needed by the pyrolysis process and to transport into the material in the reactor, a mixing apparatus and conveyor to mix and transport the raw material particles that advance in the reactor in the pyrolysis process, and channels to remove solid, liquid, and gas pyrolysis products from the reactor and which mentioned feeding apparatus has a liquid seal to maintain essentially an oxygen free condition in the reactor. The object of the invention is also the method to perform the pyrolysis process.
The intention of the invention is to make possible the advantageous chemical recycling of the plastic waste so that also the mixed polyolefin rich plastic waste can be handled and recycled in the pyrolysis process either alone or together with for example rubber waste. One product that is produced in this process is oil that can be used after continuation processing as the raw material of the monomers in the plastic industry.
The applications of the invention are the pyrolysis processes where using the before mentioned plastic waste gas, liquid, and solid pyrolysis products are produced. In these processes that are typically performed in the temperature of approximately 400-500° C. the polymers of the raw materials are chopped in an oxygen-free condition into gas hydrocarbons and using them pyrolysis oil is made by condensing. Also uncondensed gas is created in the process, which is pyrolysis gas, that consists of short chain hydrocarbons and hydrogen gas and that is used in the energy production of the process. In the mentioned pyrolysis processes, also solid pyrolysis products are formed that contain mainly carbon and inorganic compounds. The quality of the formed solid products depends on the raw material and they can be used for instance in asphalt or pigment raw material or continue treated as (recycle) carbon black the English name of which is known “carbon black”.
The first advantageous application example of the invention can be seen to be the continuously operating pyrolysis process where there is a liquid seal in the raw material feeding apparatus that can knowingly maintain essentially an oxygen-free condition in the reactor.
The second advantageous application example can be seen to be the pyrolysis process that fulfills the before mentioned conditions where all the heat energy that is fed into the reactor is produced in one equipment like boiler, heat generator, or corresponding equipment.
The third advantageous application example can be seen to be a pyrolysis process that fulfills some of the previous conditions where the raw material particles are treated more efficiently than now so that their charred isolating surfaces do not prevent or slow the pyrolysis reaction of their inner parts.
In the first one of the before mentioned application examples it is dealt in accordance with the known technique among other things so that the density of the raw material particles lighter than liquid of the liquid seat is risen higher than the mentioned liquid by a certain preliminary treatment so that also they can be made to sink to the liquid seal bottom extended conveyor that transports them with initially heavier than the liquid raw material particles to the feeding opening of the reactor. By the lighter material than the liquid seal material is meant in this document of its density (e.g. kg/dm3 lower density material and by heavier material a material of higher density.
In the Finnish patent publications F1126675 B and E1128105 B there have been presented the feeding apparatuses equipped with the liquid seal that do not include the equipments to get the raw material particles that are lighter than the liquid of the liquid seal to the conveyor that leads from the liquid seal to the feeding opening of the reactor. The drawback of these known solutions is just that the lighter than the liquid particles remain to the surface of the liquid if they are not gotten heavier than the liquid by a preliminary treatment. The preliminary treatment is disadvantageous and increases the costs of the process.
In the second mentioned application example the known technique procedure is among other things that in a boiler or other heat generator generated heat energy is lead to the wall of the reactor without dividing it in different intensities in different zones.
In the international patent publication WO202118622 A1 there has been presented a heating system of a pyrolysis reactor where in around the reactor adapted chamber burning substance is burned and the generated heat energy heats the reactor shell as a general area so that the heat energy is distributed evenly to the reactor. The drawback of this solution is different heat energy amounts being directed to different parts of the reactor. The different phases of the pyrolysis process require different amounts of energy but this solution does not obtain it.
One known way to heat the reactor is to form numerous heat energy areas and to set for each area its own heat element.
In the US patent publication US20190300794 A1 there has been presented in sections divided heating system where each section has its own heating element. The drawback of this solution is that numerous heating equipments are needed and thus the heat generation cannot be concentrated in one equipment. This is disadvantageous economically.
The third mentioned usage example situation the known technique procedure is among other things to set a screw conveyor to the reactor where the screw element while rotating pushes the raw material forwards or then a bull chain conveyor is adapted to the reactor to move the raw material forwards.
In the Finnish patent publications FI126675 B and Fil28105 B there have been presented solutions where the first mentioned has a screw conveyor and the second mentioned has a bull chain conveyor. The biggest drawback of these solutions can be seen to be that they move the raw material as bunches so that the pressure is not directed to the particles which would break their skin and get their inner parts more efficiently targeted by the heat energy. As mentioned earlier before the charring of the surfaces of the raw material particles in the pyrolisis process creates an efficient isolation layer to the surfaces of the particles that prevents the heat energy to get inside them.
The intention of this invention is to obtain such a continuously operating pyrolisis equipment and method to perform pyrolysis process that avoids drawbacks that exist in the known technique. It is characteristic for the solution according to the invention what has been stated in the characterizing parts of the claims 1 and 9.
The advantage of the pyrolysis equipment including the liquid seal according to the invention in relation to the known technique is:
In this document the term “raw material” means all the solid particles in the process, also those that have become partly or totally pyrolysis products.
The invention will be described more closely in the enclosed drawings, where
a-2c present a feeding apparatus according to the invention,
Next the construction and operation of a favorable solution will be presented referring to the before mentioned figures.
The continuously operating pyrolysis equipment according to the invention consists at least of a feeding apparatus 100, a reactor 200, a heating system 300, a mixing apparatus and conveyor 400, and channels to remove solid, liquid, and gas pyrolysis products from the reactor.
In the
The push button 7 consists of the frame 7.1 and the guides 7.2 attached to it, by the guides essentially vertically to move adapted tabular push organ 7.3 and power transfer organ 7.4 that has been fixed to the frame and the push organ to transfer the transfer power from the motor to the push organ. In this example of the invention the power transfer organ is a hydraulic cylinder.
The
Because there is a high temperature at the feeding opening 201 of the reactor certain parts of the first conveyor 8 require heat resistance capabilities. In this example the belt 8.5 is made of metal lamellas. The belt 9.5 of the second conveyor 9 has been made in the same way because this construction makes it possible for the extra liquid that has come from the liquid seal to the belt 8.5 and the raw material 2 to flow between the lamella gaps to the transfer channel 3 before falling the raw material 2 into the reactor 200.
In the
The heating system 300 according to the invention operates so that the hot gas generated in the boiler 308, heat exchanger, or other heat generator is led along the hot gas channel 309 into the distribution channel 306 from where it is distributed in relation of the cross-sectional areas Aa-Ag of the connect channels 307a-307g into the heating sections 305a-305g so that the amount of the heat energy heating the casing 202 of the reactor is greatest in the heating section 305a located mentioned casing part and smallest in the heating section 305g located mentioned casing part. The heat energy is transferred in the known way in the before described situation in the reactor casing 202 by conducting through it and then radiating into the raw material particles. The raw material particles in the beginning of the pyrolysis process need to maintain the optimal efficiency most heat energy in the beginning of the process and the least at the end. With the help of the invention, an optimal pyrolysis temperature can be achieved in each phase of the process.
In
It is possible to add to the pyrolysis equipment according to the invention in addition to the feeding apparatus 100 or the feeding apparatus and the heating system 300 an additional mixing apparatus and a conveyor 400. In the
The mixing apparatus and the conveyor 400 according to the invention operate so that while the axle 401 is rotating the ends 403 of the blades advance near the reactor casing concave sides first and lift the raw material particles from the bottom of the reactor upwards supported by the casing 202. When the blade 402 passes the horizontal level H the support of the casing starts to reduce and when the blade has risen to a certain angle α over the horizontal level the ends 403 of the blades lose their grip to the raw material particles when they glide off them and hit against the casing at the bottom of the reactor. The mentioned particles break because of repetitive hits and thus the heat energy gets without hindrance inside the particles as their charred skins get broken. The invention operation of the blades 402 thus lifts the raw material particles up from the bottom of the reactor bottom and drops them back there. As the reactor 200 has been positioned horizontal the raw material 2 advances in the reactor 200 as follows: the failing raw material lot is distributed in relation to the blade 402 that lifts it on average so that half of it comes in the front side and half in the back side (in the direction of the advance of the raw material) so that the raw material advances in a favorable speed into the direction of the process advance.
The feeding apparatus 100 liquid 4 can be pyrolysis oil that has been produced in the pyrolysis equipment according to the invention or other synthetic oil or some other for the situation suitable liquid.
The power transfer organ 7.4 of the push button operation principle can also be based on something else than hydraulics. All the ways to move the push organ 7.3 in the invention way realize the invention. As examples, chains and belts and motors to drive them can be mentioned.
The operation of the push button joint 7.5 and the turning of the push organ 7.3 regulating mechanism can be made in any favorable way. It is central in their operation that the push organ does not prevent or hinder feeding the raw material 2 into the liquid 4 during the operation.
The rotation power of the first cylinders 8.3 and 9.3 moving the belts 8.5 and 9.5 can also be created with some other than the before mentioned hydraulic motor. As an example an electric motor can be mentioned and a gear between it and the cylinder. It is also according the invention to set alternatively other cylinders 8.4 and 9.4 as drive cylinders.
The movement path of the first belt 8.5 can be supported in any known way in the down corner where its direction changes. As an example it can be mentioned glide guides adapted to the edges of the belt.
It is possible to adapt any favorable amount of heating sections 305a-305x to the equipment according to the invention and their widths Da-Dx can be made equal or different. In the before explained invention example they are equal.
The cross-sectional area sizes of the exhaust channels 311a-311x of the heating system 300 according to the invention have not as such been bound to the sizes of the cross-sectional areas Aa-Ax of the connect channels 307a-307x, they can also be larger than the last mentioned.
The heating system 300 according to the invention can also be realized so that there is not a separate distribution channel 306 but a part of the hot gas channel 309 operates as the mentioned distribution channel.
The close organ 312 can be realized in many different known ways. It is central that they can be used to reduce the flow areas of the gases going through the connect channels by regulating them either before starting the process or during it. The heating system according to the invention can also be realized in such a way that the connect channels have same size cross-sectional areas and the different flow amounts through them are achieved regulating the close organs.
The tightness of the lead-in of the axle 401 of the mixing apparatus and the conveyor 400 can be realized in the equipment according to the invention in many different ways. One functional solution is to tighten the lead-in by feeding pressurized nitrogen gas to it.
The most favorable installation manner of the axle 401 is to perform it with one lead-in but also the lead-ins at both ends of the reactor realize the invention.
The rotation power of the axle 401 can be generated and transferred to the axle in any known way. As an example an electric motor and between it and the axle adapted gear can be mentioned.
It can be seen the most favorable application from the point of view of the invention that the transition T of the blades 402 in the direction of the centre arbor is equal but also from this differing transitions are included in the scope of the invention. The width of the blades can vary within the limits that realize the invention idea of this pyrolysis equipment.
The tightening of the outlet opening of the solid pyrolysis product can be realized for instance using the product carbon statue. In this case, the solid product exiting from the reactor 200 through the opening forms at the moment of exiting a gas tight stopper in the opening.
It should be noticed that even though this explanation sticks to one for the invention favorable solution example this does not in any way want to limit the use of the invention only in this type of example usage but many variations are possible in the scope of the invention idea defined in the claims.
Number | Date | Country | Kind |
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20225211 | Mar 2022 | FI | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FI2023/050104 | 2/22/2023 | WO |