JPH0747289A - Method for regenerating spent catalyst - Google Patents

Abstract

PURPOSE:To provide a method for regenerating a spent catalyst used for desulfurization of heavy oil, by which the spent catalyst is reused without changing the chemical and mechanical structures. CONSTITUTION:A rotary kiln 1 is equipped with a rotary cylinder 3 and an exhaust pipe 25. The rotary cylinder 3 is provided with a heating part between the charging port of a raw material and a takeout port. Gas is generated in the heating part and separated from the raw material and taken out from the exhaust pipe 25. A spent catalyst being the raw material is heated by using the rotary kiln 1 and oil content and water content contained in the raw material are firstly separated and removed. Thereafter, the raw material from which the oil content and the water content have been removed is heated at 300-700 deg.C in the oxidizing atomosphere to burn and remove carbonaceous substance and sulfur content.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for regenerating a used catalyst which is used for petroleum refining and the like so as to be reusable.

[0002]

2. Description of the Related Art Most of used catalysts used for direct desulfurization of heavy oil are not profitable for treatment for effective use, and are therefore disposed of as landfill as industrial waste.

However, it is uneconomical to discard the catalyst used once as it is, and since this type of used catalyst contains oil and various metal elements, it is necessary to dispose of it in a landfill. It may cause environmental pollution. In order to solve this, it was attempted to heat the used catalyst to remove oil and carbonaceous substances and recycle it. However, during the above heating, heat generation ignited and the temperature rose to 700 ° C. The surface area was reduced and the catalyst function could not be sufficiently restored.

[0004]

Therefore, the present invention provides a regeneration method capable of regenerating the used catalyst into a reusable state without changing the chemical or mechanical structure. Is an issue.

[0005]

In order to solve the above problems, the present invention employs the following configurations. That is, the method for regenerating a used catalyst according to the present invention comprises a rotating cylinder provided with a heating part between a raw material inlet and a raw material outlet and a gas generated in the heating part separated from the raw material. By using a rotary furnace having an exhaust gas pipe capable of heating, a process of separating and removing oil and water contained in the raw material by heating a used catalyst which is a raw material, and oxidizing the raw material from which the oil and water are removed. The method is characterized by including a step of heating to 300 to 700 ° C. in an atmosphere to burn off carbonaceous materials and sulfur components.

The present invention will be described in detail below with reference to specific examples. First, as a rotary furnace used for carrying out the present invention, a raw material charged through a charging port can be heated to an appropriate temperature. A furnace that can separate the gas generated from the raw material by heating from the raw material before cooling and exhaust it is used. 1 to 3 exemplify such a furnace, and by using the furnace having such a structure,
The gas once generated can be separated and discharged without adhering to the raw material again. It should be noted that not only the rotary furnace shown in the drawing but also another furnace having a similar function can be used.

The rotary furnace 1 shown in the figure has a cylindrical rotary cylinder 3 provided inside a heating chamber 2. Rings 5 and 5 are provided on the outer peripheral portion of the rotary cylinder 3 to rotate the rotary cylinder 3. The cylinder 3 is rotatably supported on the rollers 7, 7 by this ring. A gear ring (not shown) is provided on the outer peripheral portion of the rotary cylinder, and a drive pinion for transmitting the rotational power of the motor meshes with the gear ring to gently rotate the rotary cylinder 3. There is. The heating chamber 2 is provided with heating means such as a burner and an electric heating heater, and indirectly heats the raw material in the rotary cylinder 3 to a predetermined temperature.

A raw material charging port 8 is provided at one end of the rotary cylinder 3.
Is provided, and the raw material supply device 10 is installed in this portion. The raw material supply device 10 includes a cylinder 13 integrated with a hopper 12.
And a screw type feeding device 1 provided inside the cylinder
4 is provided. A take-out port 15 is provided at the opposite end of the rotary cylinder 3, and a take-out hopper 17 is provided at this part. Further, in the middle part of the rotary cylinder 3,
A partition 19 for partitioning the inside of the cylinder is provided, and the partition divides the inside of the rotary cylinder 3 into a heating zone 3a and a cooling zone 3b. The rotary cylinder 3 is slightly inclined so that the insertion port 8 side is high and the extraction port 15 side is low. The heating chamber 2 heats only the heating zone 3a of the rotary cylinder 3 and does not heat the cooling zone.

A spiral raw material passage 20 is provided on the outer peripheral portion of the rotary cylinder.
Is provided. The raw material passage 20 has a starting end portion 21 opening to the heating zone 3a and an ending end portion 22 opening to the cooling zone 3b. The position of the partition wall 19 is detoured from the starting end portion 3a to the terminating end portion 3b, passing through the outside of the rotary cylinder. The twisting direction of the spiral raw material passage 20 is a direction in which the raw material inside is sent from the heating zone to the cooling zone side by the rotation of the rotary cylinder 3. The cross-sectional area of the raw material passage 20 is filled with the raw material supplied from the raw material supply device during operation,
The size is such that the flow of gas is blocked.

On the other hand, the rotary cylinder 3 is provided with an exhaust pipe 25 penetrating the partition wall 19 from the heating zone 3a to reach the outside of the take-out port 15 at the axial center of the rotary cylinder 3.
A cooling tower 30 is connected to the outer end of the exhaust pipe 25.

The cooling tower 30 is formed in a hollow cylindrical shape to which the exhaust pipe 25 is connected near the lower end, and a gas discharge port 31 is provided at the upper end. The middle part of the cooling tower 30 has a cooling part 32 in which a large number of cooling pipes are provided in parallel.
Has become. Then, the cooling water supplied from the water inlet 33 flows through these pipe groups and then flows out from the water outlet 34.

When the rotary furnace 1 is used, the rotary cylinder 3
While slowly rotating the rotary drive device, the granular material held in the hopper 12 is fed by the screw type feeding device 14 in an appropriate amount, that is, the exhaust pipe 25.
Is not supplied into the opening 25a on the heating zone side, and is supplied into the rotary cylinder 3 in an amount sufficient to fill the spiral raw material passage 20. This raw material is gradually sent to the partition wall side as the rotary cylinder rotates and the inclination of the rotary cylinder increases.
When heated to 0 to 400 ° C., oil and water contained in the raw material are gasified and separated from the raw material.

The raw material that has moved to the partition side from the heating chamber is obstructed by the partition, and the raw material passage 20 from the starting end portion 21 is blocked.
It enters inside, bypasses the outer peripheral portion of the furnace body 3, and is transferred from the terminal end portion 22 into the cooling zone 3b. Then, it is cooled while moving in this cooling zone and taken out from the take-out port 15. On the other hand, since the raw material passage 20 is filled with the raw material, the gas vaporized from the raw material is discharged to the outside of the rotary cylinder through the exhaust pipe 25 provided in the core portion and introduced into the cooling tower.

The gas introduced into the cooling tower rises in the tower and is discharged from the gas discharge port 31. During this time, the gas is cooled by the water cooling pipe group of the cooling unit 32, and the oil and water contained in the exhaust gas are cooled. Liquid components such as and the like are condensed and become drainage, and flow out from the liquid outlet 36 at the bottom. The leaked liquid is stored in tank 3
It can be stored in 7, but because oil and water have different specific gravities
It is divided into layers and stored. Then, the oil O is taken out 38
Therefore, the water W is separately taken out from the take-out port 39. The oil thus separated is effectively used as fuel or the like.

If the above heating is carried out in the atmosphere, the catalyst will be ignited immediately and the pores of the catalyst will be crushed, and the main component of the catalyst, alumina, will be changed from β-alumina to α-alumina and used as a catalyst. Although it cannot be used, when a rotary furnace as shown in the drawing is used, the gas generated from the raw materials suppresses the formation of an oxidizing atmosphere in the furnace, and such a problem does not occur. If the heating temperature in this case is too low, the gasification of volatile components such as oil and water will not be sufficiently carried out, and if it is too high, the pores of the catalyst will be crushed and the specific surface area will be small, and the adsorption effect will be reduced. In the case of a used catalyst, 300 as above.
The temperature is preferably set to 400 ° C. It should be noted that, depending on the type of raw material, temperatures other than this can be adopted.

The raw material from which oil and water have been separated and removed by heating in a rotary furnace is then heated in an oxidizing atmosphere to oxidize and burn adsorbed carbonaceous material (coke) and sulfur. Let A normal oxidation roasting furnace, for example, a rotary kiln can be used for this heating. The heating temperature in this oxidizing atmosphere is preferably 300 to 700 ° C, and more preferably 400 to 500 ° C.
If this temperature is too high, the specific surface area of the catalyst becomes small as described above and the catalyst strength also decreases, which is not preferable. If this temperature is too low, the removal of coke, sulfur, etc. will be incomplete.

As described above, the combination of deoiling and oxidative roasting makes it possible to suppress rapid heat generation and ignition in the regenerating process, simplify temperature and air amount adjustment, and are optimal for various catalysts. It becomes easy to select a proper regeneration condition.

[0018]

EXAMPLES Examples of the present invention will be specifically described below. Using a used catalyst containing the components shown in Table 1 and the other component being β-alumina as a raw material, oil and water were removed using the rotary furnace of the illustrated example. Heating condition is 350 ℃
It was x7 hours. The ingredients other than alumina of the raw material after the heating were as shown in Table 2.

[0019]

[Table 1]

[0020]

[Table 2]

The raw material that has been deoiled is a conventional raw material.
Heating in an oxidizing atmosphere using a tarry kiln,
Sulfur content was removed by burning. This oxidation roasting condition is 450
It was 4 ° C. × 4 hours. The components and physical properties of the raw material after the treatment, that is, the recycled product, are as shown in Tables 3 and 4. As can be seen from these results, the regenerated catalyst obtained had almost the same characteristics as a new product.

[0022]

[Table 3]

[0023]

[Table 4]

[0024]

As described above, according to the method for regenerating a used catalyst according to the present invention, the used catalyst used for petroleum refining or the like can be regenerated to a sufficiently reusable state. It has become possible.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a rotary furnace.

FIG. 3 is a sectional view of the rotary cylinder.

[Explanation of Codes] 1 rotary furnace 2 heating chamber 3 rotating cylinder 3a heating zone 3b cooling zone 19 partition wall 20 raw material passage 25 exhaust pipe 30 cooling tower

Claims (1)

[Claims] 1. A rotary furnace having a rotary cylinder having a heating part provided between a raw material inlet and a raw material inlet, and an exhaust pipe capable of separating and extracting gas generated in the heating part from the raw material. By using the used catalyst, which is a raw material, to separate and remove oil and water contained in the raw material, and heating the raw material from which the oil and water have been removed to 300 to 700 ° C. in an oxidizing atmosphere. And a step of burning and removing the carbonaceous material and the sulfur content.