DEVICE FOR CONTINUOUS PRODUCTION OF DERTVATES FROM
OIL SHALES AND SOLID PLASTIC WASTE
DESCRD7TTON OF THE INVENTION
Invention field
This invention refers to the new technology of thermal separation- by the process of continuous thermal cracking - concerning gaseous, fluid and solid derivations of oil shales, bituminous sands, solid plastic waste, communal waste with a high content of plastic, bituminious and metable resins.
Tehnical problem
In case of decomposition of oil shales, bituminous sands and solid plastic waste te problem is the discontinuity of the process. The mass is brought in special spaces that must be hermetically sealed. There the mass is heated up anad gradually various gaseous and liquid derivations of hydrocarbons are separeted. After the termination of the process the mass is cooled, reomoved from the device and the process is completely repeated. A lot of work and energy is used. Therefore the process isn t economical in most cases and is applired mainly in case od plastic refuse dressing - on condition that the refuse doesn t have a major content of admixtures.
Status of technique
The problem of production of petroleum obtained from oil shales and bitumimous sands isn't solved in an economically satisfactory manner. Although there are huge resoruces of oil shales and bituminous sands worldwide and although they have a high content of various derivations of hydrocarbons, there still hasn' been developed an economical process of separation of liquid from solid components. The separation is achieved by heating up. In such a way of lot of energy is usred. Thechamber for heating up oil shales must first of all be filled up to the top and afterwards hermetically sealed. The heating up causes the separation of liquid fractions (conducted from the bottom of the chamber) and gaseous fracations (conducted from the top of the chamber). By the raising of temperature various fractions are separated until the solid material is the only one left, in the same way the separation of waste having a high content of plastic takes place. For the reason of lack of economy there are only few industrial plants world-wide where petroleum is obtainmed from oil shales, bituminous sands or plastic waste. The exception in utilization of plastic waste is the pure plastic waste consisting of meltable plastics. It is sufficient to grind such waste and afterwards it can be used in further production.
Presentation of the essence of the invention
The primary goal of this tecnology is a sheap, continuous and quick thermal decomposition into derivates of oil shales and bituminous sands, taking up a small space and requiring very little human work.
The secondary goal is to make a sheap, continuous and quick heat treatment of various plastics, bituminous, resinous and rubber waste possible.
A further objective is to make a heat treatment of communal waste, without previous spearation of waste, possible (in such a treatment the separation of following part occurs: those parts of waste that are melting in case of heating up).
The advantages of the technology shall be presented in the following description.
The device for continuous production of derivates from oil shales,bituminous sands and solid plastic waste consists of three main pieces that the material subjected to hat treatment and separation of liquid and gaseous derivates has to pass trough. The fresh mass subjected to treatment is added to the first piece, an input space, where the material is immersed in water. The mass in the water slides diagonally and gradually downwards. It enters the second piece of the device that looks like a diagonally laid tube. The heat treatment process takes place in the same. The tube in question is narrowed on the upper side. The gas ana water vapor (generated during the process of heat treatment of the material) concentrate at the top of the thermal tube. The bottom of the input tube is rounded and below the level of the entrance in the thermal tube. Therefore, the mass from the input space enters the thermal tube from bolow by menas of a screw conveyor, driven by an electromotor. In th thermal tube generated gas and water vapor create a pressure that keeps the water level in the input space bolow the lower level of the entrance in the thermal tube. So, the water doesn't enter the thermal tube. This pessure creates a difference in the water level (h) in the upper part of the input space and the water level at the entrance in the thermal tube. This pessure has to be kept on a constant level, in order to prevent the penetration of water into the thermal tube - if the pressure decreases i.e. in order to prevent an uncontrollable discharge of gases through the input space - if the pressure is increased. The control of pressure is carried out by regulation of discharge of gases through the output gas tube. The mass that entered the thermal tube gradually slides downwards and is heated by gases ant water vapor rising from the bottom to the top. The heat arises from the gas of electric heater located in the middle of the lower part of the thermal tube. The heater heats the mass in order to reach the necessary temperature. The thereby generated gases and vapor are rising upwards. They give off their heat to the mass they are going through and they gradually cool. During this process particular gases condense to liquid and flow, at the bottom of the thermal tube, downwards and flow in a number of derivation pipes used to discharge various liquid derivates- under pressure - from the thermal tube. The heated mass passes by the heater and slide to the output space with water. During this process the mass gives off its heat to the strongly evaporating water. The overheated water vapor rises and thus assumes the heat from the material the vapor passes through. The material itself
cools. The water vapor reaches the max. temperature on the level of the heater. By further moving up the water vapor becomes colder and colder. The water in which the mass is immersed in the input space ant the water in the output space serves as a gasket that prevents an uncontrolled discharge of gas through the input and output space. The thereby generated water vapor serves as a heat trasmitter. The water level in the external part of the output space and the part of the output space, that is connected with the thermal tube, isn't the same i.e. because of the gas pressure a difference in the water level (h) occurs in the thermal tube. This difference is equal to the difference in the water level in the space. The cooled mass is removed from the output space by means of an elevator. It is necessary to add that amount of water to the input space that is equal to the evaporated water in the thermal tube.
The evaporated steam is condensed to liquid at the top of the thermal tube. Therefore, the water must be constantly conducted from the input tube, in order to keep the level same. The gas is conducted through the output gas tube to the reservoir and it is necessary to keep it under approximately constant pressure, while the liquid derivates are conducted to reservoirs for various derivates.
Short description of the drawing
The herewith annexed drawing, included in the decription and component of the description of the invention, shows the longitudinal section of the device and helps to explain the treatment technology. As can be seen from the drawing, the mass is added to the process in the input space (1). By means of a screw conveyor (7), driven by an electromtoor (8), the humid mass enters the thermal tube (2). The mass slides the aslant thermal tube (2) downwards. During that time the mixture of waste and water slides towards the thermal tube (2), passes by the heater (9) by and continues to slide towards the output space (3). From there it is removed by an elevator (5). It can also be seen that the gas generated in the thermal cracking process collects at the pop of the thermal tube (2), where it leaves thrugh a gas pipe (4). The liquid derivates leave through output derivate tubes (6) to reservoirs for diferent derivates.
Detailed description of at least one way of implementation of the invention
As can be seen from the drawing the device for continuous production of derivates from oil shales and solid plastic waste consists of an input space (1), vhere oil shales, bituminous snds, plastic waste or communal waste having a high content of plastic, bituminous, resinous and rubber waste are added, this input space is filled with water. In such a way a humid mass (10) is obtained. The mass in questionslides downwards. The immersed mass settles and gradually slides towards the entrance in the thermal tube (2). By means of a screw conveyor (7), driven by an electromotor (8), the mass comes from below into the thermal tube (2), where the thermal cracking process takes place. In the thermal tube (2), accompanied by gradual heating up caused by gases that go from bottom to the top, the mass slides slowly towards the output space (3). The mass crosses a number of derviation tubes (6) located at the bottom of the thermal tube (2). Through those derivation tubes (6) the melted derivates come out. In the lower part of the thermal tube (2) there is a gas or an electric heater (9) that heats up the mass in order to reach the desired temperature. The heated mass continues to slide downwards and enters the water located in the output space. The water evaporates quickly and the mass cools quickly. The generated water vapor moves up and additionally heats up until the heater (9). Afterwards, by further movement upwards, it starts to give off the acquired heat to the mass that slides towards the heater (9). This water vapor serves as a heat exchanger i.e. the water vapor assumes the heat from the mass at the bottom of the thermal tube (2). Useful derivates have been strained from the mass. At the entrance in the output space (3) the mass is cooled until it reaches the space temperature and the elevator (4) takes i to the surface. Quite a lot of water is needed in the output space (3) in this working process. The water has to be added constantly. At the same time, the condensation of water vapor at the top of the thermal tube (2) causes the increase in the quantity of water in the input space (1). The water excess drains off and returns to the output space (3). Thus the constant water flow, in the opposite direction of the cracked mass, is kept.
The difference in the water level (h) in the upper and lower part of the input space (1) and in the upper and lower of the output space (3) is equal ant it has to be kept constantly on the same level. This difference in the water level is caused by a higher pressure of gases in the
thermal tube (2). Also that pressure has to be keopt constantly on the same level by regulation of quantity of gases discharged in the gas reservoir. Should the pressure decrease, the gas discharge at the outlet gas tube (5) must be decreased in order to prevent the water penentration from the input space (1) into the thermal tube (2). Should the pressure exceed the optimum, the discharge of gases at the outlet gas tube (5) must be increased, in order to prevent the uncontrolled discharge of gases through the input space (1) ant output space (2).
Manner of application of the invention
In such a way the invention of the device for continuous production of derivates from oil shales and plastic waste makes the utilization of oil shales, bituminous sands, various plastic waste and communal waste having a huge content of plastic and bitumen for the production of energetically valuable gases and liquid derivations of hydrocarbons possible.
The oil shales and bituminous snads having a hih percentage of resin and bitumen are the best material for treatment. However, aso the rest is most compact.
By this technology we can directlu treat the communal waste, a big ecological problem in cities, without previous sepration - on condition trat the waste has enough plastic waste, rubber, bitumen or resins. The waste that can be melted by heat or that ca be evaporated is discharged through outlet gas or derivation tubes in reservoirs and the residual waste, consisting of metal, ceramics, glass and stone can be used in the building trade.
During the thermal cracking process the coke is created as a solid residiuum. If we want to extract coke for further utilization, we use an electric heater for the heating up of the thermal tube. If we don't need the coke at that very momoent, we use - for the heating up of the process - a gas heater having a smaller content of gas and a higher content of air. Thus, the coke is connected with the oxygen excess and burns out in the thermal tube. For the heating up we can use gases generated during the cracking process and we can also use hydrogen. If we use hydrogen and burn it with a small quanitity of air, the hydrogen excess is connected with the coke and thus we increase the quantity of liqud and gaseous fractions of hydrocarbons. If we keep the temperature in the thermal tube on a sufficently high level, we can extract, as a by - product, the easily meltable metals and even glass.