DE3605756A1 - Process for the low-temperature carbonisation of hydrocarbon-containing residues - Google Patents

Abstract

In this process for the low-temperature carbonisation of hydrocarbon-containing residues and similar materials, the high abrasion of the low-temperature carbonisation plants used in accordance with the prior art is to be avoided by an armoured drum wall and grinding bodies as a cleaning device. Therefore, these substances in the liquid to pasty state are applied, along the outer tube shell circumference, to a rotatably mounted tube, which is shell-heated by a heat transport gas and arranged in a gas-tight housing, and the low-temperature carbonisation gas generated and the solid low-temperature carbonisation residue, which falls off itself after about 1/2 or 3/4 of a rotation of the slowly rotating tube or is removed by a scraper apparatus, are taken off from the housing via separate branches or discharge apparatuses.

Description

The invention relates to a method for smoldering hydrocarbon residues in the Preamble of claim 1 specified type.

A detailed description of a Residue carbonization of the hydrogenation residues of the There is catalytic pressure hydrogenation of coal in "The catalytic hydrogenation of coal, Tars and mineral oils ", Springer-Verlag, Berlin / Göttingen / Heidelberg, 1950, page 252 to page 254.

The rotary kilns used for this purpose consist of a rotatable and weak against the Horizontal inclined drum by a surrounded by a gas burner heated by a gas burner is. Located on the two ends of the drum the fixed entry and discharge housings.  

The feeder for the are located on the entry housing smoldering residue and the smoldering gas outlet. At the The discharge housing is the solid discharge.

The drum consists of the externally heated cylindrical part, the device for cleaning the inner wall and the storage facilities for Drive and for sealing.

The residue to be smoldered is preheated and Entry housing pumped into the drum. By Indirect heat transfer is included in the feed the goal of gaining usable Hydrocarbon products that on Smoldering gas outlet connection removed as product be sworn. The resulting smoked coke will together with those that were in arrears Solids through the cleaning device from the Drum wall removed and leaves relatively fine ground the rotating drum over the discharge housing.

The cleaning device is used to Caking and formation of agglomerates tend Remove residues from the drum wall. In order to is inevitably a grinding of the resulting coke connected.

The used according to the state of the art Smoldering plants had an armored drum wall and Grinding media as a cleaning device. This resulted excessive wear on the drum wall; it came to  Removal of up to 2 mm / month. The very high one Load on the drum by the weight of the Grinding media filling led to crack formation in the Drum wall and often even to break. By the high thermal and mechanical stress of the Rotary drums are a satisfactory service life difficult to reach.

The object of the invention is to overcome these disadvantages to avoid known methods and devices.

According to the invention, this object solved that

• a) these substances in a liquid to pasty state on a rotatably mounted by means of a Heat transfer gas jacket-heated and in one gas-tight casing arranged lengthways applied the outer circumference of the pipe jacket be and
• b) the carbonization gas generated and that after about ½ or ¾ revolution of the slowly rotating Pipe dropping by itself or through a pipe Scraper removed fixed Smoldering residue via separate nozzles or Discharge devices withdrawn from the housing will.

In this process, the thermal Treatment by smoldering does not require heat from  outside but from the inside via the rotatably mounted cylindrical drum on the outside Transfer the input material indirectly. While with the State of the art method of smoldering in If the longitudinal direction progresses inwards, it runs Smoldering in the present proceedings over the Circumference of the drum from the outside.

The gaseous smoldering products in the External space of the drum pulled off while the Solids together with the coke that forms first stick to the drum, then after about 2701 turn off or by a suitable one Scraper device away from the drum wall will. The coke is then drawn off in the lower one Part of the outside space.

Diameter and speed of the drum and thus the Dwell time of the good to be smoldered up to its Distance, d. H. Cleaning of the Drum surface, are product specific. Material properties such as viscosity, boiling curve, specific heat, smoldering heat, thermal conductivity of influence.

The rotatable drum consists of a Double tube made of inner tube and jacket tube. By the The heat transfer gas, e.g. B. flue gas, headed.  

The product to be smoldered is applied to the surface of the outer jacket tube applied, which is gaseous resulting product in the surrounding housing upwards is subtracted. The coke along with the Solid components are preferably in the lower Area of the housing and possibly by means of a Trigger device deducted.

The surrounding housing is through at the pipe ends radially arranged seals sealed so that Gas transfer from the flue gas side to the product side or vice versa.

The heat transfer gas is conveniently located inside Channels guided, which are adjustable via flaps, so that the heat supply to the smoldering zone different needs can be adjusted and thus most of the surface of the casing tube can be fully used for heat transfer.

The heat transfer gas is expedient outside of actual smoldering device. So you can all available fuels for the Covering the smoldering heat can be used.

The residue of the Smoldering process from the surface of the casing pipe removed, creating a clean wall which is maintained at all times ensures the best possible heat transfer.  

The load-bearing is made by a heat-insulating cladding Inner tube thermally insulated from the heat transfer medium, the inner tube also with a cooling gas can be applied. This will make the Maintenance of mechanical strength and Resilience of the supporting inner tube and thus to practice the present procedure belonging device guaranteed.

Be compared to the state of the art according to the invention the advantages explained below realized.

The cleaning of the on the surface of the Cladding tube layer is simple Means, e.g. B. scrapers, brushes feasible, wherein the cleaning effect is facilitated in that in the event of caking on the outside of the casing tube of devices according to the prior art existing support effect (vault effect) is eliminated. The Smolder residue flakes off more easily and is lighter to remove. Due to the small distance between the Smoldering tube and the walls of the surrounding Gas housing is the gas space and thus the dwell time the resulting sulfur fumes are very low. It will a quick withdrawal of the resulting products from the Smoldering zone reached, causing crack reactions are much less likely. For Cleaning, inspection and repair purposes easier access to the smoldering pipe surface possible through appropriate openings in the gas housing.  

The cross sections and arrangement of the alleys for the Passage of the heat transfer gas between the inner tube and Jacket tube can be chosen so that it is also on the inside of the jacket tube to optimal Heat transfer comes. Because the thermally stressed Jacket tube has no supporting function, can Wall thickness can be chosen accordingly small. This leads to the saving of expensive, high-temperature steel.

There are no limitations with regard to the length of the carbonization tube more given to the extent than with devices the state of the art.

The heat transfer gas used for heat transfer z. B. flue gas, superheated steam u. Like., Can by the fixed at the pipe ends and Deflection chambers are distributed so that over the heat distribution over the entire pipe surface Heat requirements of the smoldering process can be adjusted. Local temperature increases that affect the process can adversely affect the product side be avoided. Because the one needed for the process Smoldering heat can be generated externally, the high measurement and control expenditure for the Burner control as for systems according to the state of the Technology.

Sensor for measuring the wall temperature of the Jacket tube can from the cooler inner tube to the hot jacket wall can be introduced. Through the Attachment of transducers in the inner tube can  analog measurements via sliding contacts or External radio connections displayed will. By measuring the Pipe wall temperature and the gas space temperatures is precise control of the smoldering process is possible. Since in the inventive method and the Implementation of the process suitable devices the heavy ones customary in the prior art Grinding media, the total weight of which is several tons identified, dropped and since the pipe ends are open, can be stored on the outside of the drum or races attached to the pipe on rollers to be dispensed with. The storage takes place on both End faces of the inner tube on pins. This is more precise guidance and smoother running guaranteed.

By not using races, the tube can be continuously protected against heat loss.

Through appropriate control flaps in the Flue gas ducts on the end faces can Heat supply over the pipe circumference according to the required amount of heat for the smoldering process the circumference of the casing tube optimally adjusted will.

Fig. 1 shows a flow diagram of an exemplary embodiment of the inventive method with appropriate hardening and output products and the main units.

To smoldering, for example a temperature of 200 ° C having use products 1 are further heated over a Einsatzvorwärmer W 1 to 370 ° C and applied to the consisting of a jacket-heated and disposed in a gas-tight housing tube carbonization drum C. 1 The carbonization gas 2 leaves the carbonization drum C 1, for example at a temperature of 500 ° C., at the same time solid (residue) 3 is removed. To apply the smoldering heat, heating gas or heating oil and combustion air 5 are fed to the heating gas generator D 1 . The combustion air is preheated in the air preheater W 2, for example, 400 ° C, an Wälzgasgebläse V 1, a part of the carbonization drum C 1 having a temperature of for example 750 ° C heating gas leaving through the Einsatzvorwärmer W 1 a in the heating-gas generator D 1 with Temperature of, for example, 600 ° C returned. The rest of the heating gas is added to the chimney via flue gas preheater W 2 at a temperature of, for example, 200 ° C. as flue gas 6 . The heating-gas generator D 1 leaves a heating gas with a mixing temperature of for example 900 ° C, which is guided in the low-temperature carbonization drum C. 1

The invention is explained in a more detailed illustration of a device for carrying out the described method in FIG. 2. The device is divided into three main groups:

• a) the rotatably mounted drum (casing tube) A _{1-8 ′}
• b) the stationary gas housing B _{1-8 ′} enclosing the drum
• c) the distribution chambers C _1-5 arranged stationary on the open end of the drum.

The drum consists of an outer tube A ₁ and A ₂ an inner tube. The annular gap thus formed is closed on one end of the drum. In the axial direction, a plurality of webs A ₄ (continuous sheets) between the inner tube A ₂ and outer tube A ₁ are arranged in a ring. These have the task of supporting the outer tube A ₁ and producing a separation of the hot flue gases flowing in opposite directions in the axial direction. The webs end on the closed end faces at an appropriate distance in order to be able to deflect the hot gases flowing through the drum. The inner tube A ₂ is provided on the outside with thermal insulation A ₃. This prevents heat loss and does not affect the static of the drum due to heat transfer.

The inner tube A ₂ is connected to a centrally arranged shaft A ₅. Bearings A _{6 + 7} are located at both ends of the shaft. The drive A ₈ of the drum is located on one side of the shaft.

The gas housing B _1-8 enclosing the rotating drum consists of a lower part B ₂ and an upper part B ₁.

In the lower part B ₂ of the gas housing, the solids which have fallen off or been cleaned off are collected. These are passed through a suitable shape of the lower part B ₂ or a suitable device from the solid outlet B ₅.

In the upper part B ₁ of the gas housing are the nozzles B ₃ arranged in the axial direction. These are arranged in such a way that the char can be applied evenly over the entire length of the drum. The carbonized material is fed through the distributor pipe B ₄, with which the nozzles B ₃ are connected.

Offset by approx. 2701 in the direction of rotation of the drum, one or more cleaning devices B ₇ are arranged over the drum length coated with carbonized material. The attachment and adjustment of the Abreinigungsvorrichtungen B ₇ takes place from the outside of the gas housing B ₁. The bushings are sealed by suitable devices.

The carbonization outlet port B ₆ is arranged one or more times at suitable points in the gas housing in order to draw off the carbonization gas uniformly.

At the drum ends, the gas housing upper part B ₁ and lower part B ₂ is sealed to the atmosphere with dynamic seals B ₈ attached to the drum.

The inlet chamber C and the outlet chamber C ₂ are located on the open end of the drum. These are used to distribute or collect the hot gases required to heat the drum.

The inlet chamber C ₁ and outlet chamber C ₂ are arranged in a ring and designed such that the hot gases in the gases between the inner tube A ₂ and outer tube A ₁ the drum enter and can be deflected.

In the inlet chamber C ₁ and outlet chamber C ₂ control flaps C ₃ are arranged radially at each inlet and outlet to the drum. Through these flaps C ₃ the drum can be acted upon differently with hot gases over its circumference.

The hot gas inlet nozzle C ₄ ₅ inlet and outlet connections C are connected at a suitable point in the entry chamber and exit chamber C ₁ C ₂.

The sealing of the hot gas chambers C ₁ and C ₂ takes place on both ends on the inner tube A ₂ and the outer tube A ₁ with the radially arranged dynamic seals C ₆.

. The device shown in Figure 3 is divided as in Figure 2 in three main groups.:

• a) the rotatably mounted drum (casing tube) A _{1-8 ′}
• b) the stationary gas housing B _{1-8 ′} enclosing the drum
• c) the distribution and deflection chambers C _1-7 arranged stationary on the end faces of the drum.

The annular gap of the drum formed by the outer tube A ₁ and the inner tube A ₂ is open at both ends.

The webs A ₄ arranged in the axial direction end on both ends with the drum tubes A ₁ and A ₂.

The deflection chamber C ₇ is located on the end face opposite the inlet and outlet chambers. The deflection chamber is divided into several sections for deflecting the hot gases, corresponding to the number of entries and exits of the entry chamber C ₁ and exit chamber C ₂.

The stationarily arranged deflection chamber C ₇ is sealed to the outer tube A ₁ and A ₂ inner tube by dynamic seals to the environment.

Due to the deflections assigned to the individual inlet and outlet chambers, regulation of the hot gases to adapt to the different heat requirements on the circumference of the drum is only required at the inlet chamber C 1.

Summary

In this method of smoldering hydrocarbonaceous residues and the like The high wear of the according to the state the smoldering systems used with the technology armored drum wall and grinding media as Cleaning device can be avoided.

Accordingly, these substances are in liquid up pasty state on a rotatable means of a heat transfer gas jacket-heated and in one gas-tight housing arranged along the pipe outer tube circumference applied, and it will the carbonization gas generated and after about ½ or ¾ Rotation of the slowly rotating pipe from self-dropping or by a scraping device removed fixed smoldering residue over separate Nozzles or discharge devices from the housing deducted.

Claims (5)

1. Process for smoldering hydrocarbon-containing residues from the distillative, thermal or extractive treatment of mineral oils; the high pressure hydrogenation of coal, tars, mineral oils, their distillation and extraction products and similar substances, characterized in that

• a) these substances are applied in a liquid to pasty state to a rotatably mounted tube which is heated by a heat transfer gas and arranged in a gas-tight housing along the outer circumference of the tube shell and
• b) the carbonization gas generated and after about ½ or ¾ rotation of the slowly rotating tube of self-dropping or removed by a scraping device fixed carbonization residue are removed from the housing via separate nozzles or discharge devices.

2. The method according to claim 1, characterized in that that the sensible residual heat of the heat transfer gas is used to preheat the feed. 3. The method according to claim 1, characterized in that for setting the temperature of the heat transfer gas cooled recycled heat transfer gas is admixed. 4. The method according to claim 1, characterized in that the heat transfer gas means in the annular gap of the jacket-heated pipe arranged Guide elements and adjustable flaps or the like. to be led. 5. The method according to claim 1, characterized in that the supporting inner tube of the jacket-heated Pipe through a heat-insulating casing of the Heat transfer gas is thermally insulated and if necessary is still supplied with a cooling gas.