KR19990003410A - Sulfur recovery device - Google Patents

Abstract

The present invention relates to a device for removing sulfur vapor and recovering sulfur particles by using a sulfur vapor generated during operation of a molten sulfur storage tank using a cooler and a filter. By inserting the cooler at an angle, the cooling performance of sulfur vapor is improved, and the safety of the tank is increased by the positive and negative pressure safety devices located above and below the cooler.The filter placed on the safety device has a continuous porosity to minimize the pressure loss. Membrane coated material, which is used to cool sulfur vapor generated during the operation of molten sulfur storage tank by using a cooler to change to particulate form, clean air is discharged through the filter and sulfur is returned to the tank. do. By using such a device, the sulfur vapor generated in the molten sulfur storage tank is sufficiently cooled by the internal cooling fins, thereby improving the cooling performance, increasing the life of the filter, removing the sulfur vapor and increasing the recovery efficiency of the sulfur particles. It is easy to check and clean the sulfur particles deposited on the filter and to inspect the filter.

Description

Sulfur recovery device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sulfur recovery apparatus, and more particularly, to a sulfur recovery apparatus for removing and recovering sulfur from sulfur particles and sulfur vapor generated in a vent section of a molten sulfur storage tank.

Sulfur has a melting point of about 119 ℃ and is a yellow solid at room temperature. Sulfur is produced as a by-product in the refinery's heavy oil reforming process. Refineries store sulfur, a byproduct, in storage tanks in molten sulfur for convenient shipping. When molten sulfur has a temperature of 155 ° C. or higher, a phase change occurs and becomes a brown high viscosity phase, resulting in poor fluidity. Thus, the storage temperature in the molten sulfur storage tank is maintained at approximately 135 to 145 ° C.

The molten sulfur stored in the storage tank is loaded into the tank through the shipping facility and transported to the demand. The molten sulfur is lost in the product due to transportation loss, respiration loss, inflow loss, etc. while the sulfur is stored and operated in the tank. Steam will be generated. The vapor is released into the atmosphere and then air-cooled to turn into yellowish sulfur particles that diffuse into the atmosphere. These sulfur particles are harmful to the human body can cause respiratory diseases if inhaled, may also cause odor. In addition, when the emitted sulfur particles are exposed to steam leaking from the steam pipe for keeping the tank warm, serious corrosion may occur. Therefore, there is an increasing demand in the art for a technique for removing and / or recovering sulfur vapor and / or sulfur particles.

There are several types of installations for the prevention of air pollutants, but they are usually classified according to whether the target pollutant is a gas phase or a particle phase. Techniques to prevent gaseous contaminants include oxidation, catalytic oxidation, adsorption, cleaning, condensation recovery, etc.Avoiding techniques for preventing particulate contaminants include gravity sedimentation, cyclone, wet scrubber, A back filter, an electrostatic precipitator, and the like.

In the particulate air pollution prevention technology, in general, when the particles are 50 μm or more, the gravity sedimentation method using gravity sedimentation can be adopted. When the particles are 1 μm or more, the centrifugal force can be used for the cyclone method. If the size is 0.01㎛ or more, scrubber cleaning method can be adopted to remove particles by spraying water, and if the particle size is 0.01㎛ or more, a bag filter method using a bag house type filter can be adopted. In the case of small particles, an electrostatic precipitating method capable of treating fine particles of about 0.005 μm using static electricity may be applied.

On the other hand, sulfur vapor discharged from the vent of the molten sulfur storage tank is cooled by air immediately after the release, and some of the sulfur contained in the sulfur vapor changes to a particulate state, thus removing and / or recovering contaminants mixed with solids and gases. It is not suitable to apply the method described above, which is limited to either weather or solid phase.

Accordingly, the present applicant is the sulfur vapor of the molten sulfur storage tank in which the sulfur vapor generated during the operation of the storage tank is cooled through the cooler to change into particulates, and then filtered through a surface filtration filter to discharge only clean air to the atmosphere and recover the sulfur back into the tank. And a device for removing particles for the first time and filed with Korean Patent Application No. 1994-33287, and equipped with a mobile surface filtration filter that can operate as an open vent according to the change of the positive and negative pressure in the storage tank. Invented sulfur vapor removal and particle recovery apparatus by a mobile surface filtration filter and filed with Korean Patent Application No. 1996-5255.

These inventions can simultaneously process sulfur vapor and sulfur particles generated from the vent of the molten sulfur storage tank, but to cool the sulfur vapor by attaching an external cooling fin to the cooler body, the sulfur vapor flows into the cooler. By adopting the method of heat exchange with the wall surface of the heat exchange area is small compared to the volume has a problem that the length of the cooler must be very long to be sufficiently cooled. If the length of the cooler is not long enough, sulfur vapor is not sufficiently cooled and does not change into particulates, so the amount of sulfur deposited on the filter increases, which shortens the life of the filter and decreases sulfur vapor and particle removal efficiency. In addition, the above-described inventions have a problem in that the length of the cooler is limited due to safety problems, and at the same time, it is difficult to check and clean the sulfur particles deposited in the cooler, check the filter, and the like.

Accordingly, the present invention is to provide an improved sulfur recovery device, which can effectively remove and recover sulfur vapor and sulfur particles simultaneously to prevent air pollution, as well as having a simple structure, long filter life, and simple operation. It is a task.

1 is a view schematically illustrating a structure of a sulfur recovery device according to an embodiment of the present invention for removing and recovering sulfur from sulfur vapor generated in a vent part installed on a vent part of a molten sulfur storage tank.

2 is an exploded perspective view showing the structure of the pressure regulating means 30 of the sulfur recovery device of FIG.

3 is an exploded perspective view showing the structure of the filtration means of the sulfur recovery device of FIG.

Figure 4 is a view for explaining the structure and operating principle of an embodiment of the cartridge type cooling means applied to the sulfur recovery device according to the present invention

* Explanation of Signs of Major Parts of Drawings *

10: distribution means 20: cooling means

21: cooling fin 22: handle

23 frame 30 pressure control means

31: duct 32: static pressure control plate

33: negative pressure control plate 34: negative pressure control plate cover

40: filter means 41, 42: filter frame

43: filter 50: cover

61, 62: confirmation window 70: flange

80: fixed cable

According to the present invention for solving the above problems, in the apparatus for recovering sulfur from the sulfur vapor discharged from the vent of the molten sulfur storage tank,

The apparatus comprises one or two or more cartridge type cooling means for cooling the sulfur vapor and filtering means located above the cooling means; The cooling means is provided with a sulfur recovery device, characterized in that the cartridge-type cooling means removably inserted into the cartridge at a plurality of cooling fins at regular intervals.

Hereinafter, the present invention will be described in more detail.

The sulfur recovery apparatus of the present invention includes a cartridge-type cooling means in which a plurality of cooling fins are detachably arranged at regular intervals, and filtering means disposed on the cooling means. Although not intended to be limiting, it is preferable that the cooling fins be installed obliquely inside the cartridge to increase the cooling efficiency. The air is designed to flow through the cooling fins, and sulfur vapor and sulfur particles supplied from the vent portion of the molten sulfur storage tank are distributed between the cooling fins in the cartridge.

In the apparatus of the present invention, the cartridge type cooling means is arranged in one or two or more stages, more preferably in two or more stages. In the case of arranging the cooling means in multiple stages, an appropriate stage is determined according to the cooling efficiency. This is because when sulfur vapor is cooled and converted into particles, it may interfere with heat conduction, and the distance between the cooling fins may be narrowed, which may block the flow path of the fluid and increase the pressure in the tank. The cartridge type cooling means of each stage may use the same thing, or may have a different structure. That is, the cooling means of each stage may equalize or different the number, the inclination angle, and the like of the cooling fins disposed therein. The cooling fins of the cartridge type cooling means are preferably arranged obliquely, since sulfur vapors rising from the inside of the tank form turbulence and hit the surface of the cooling fins to increase the cooling efficiency. In addition, it is preferable that the cartridge type cooling means of each stage is detachably installed in order to check the sulfur particle state inside the cooling means at any time and remove the attached sulfur particles.

In the present invention, in order to increase the cooling efficiency of sulfur vapor, it is preferable that a plurality of rectangular tube type cooling fins are inserted into a rectangular cartridge, and the number of cooling fins per cartridge is 5-7.

Cooling fins are inserted across the inside of the cartridge and each end of each cooling fin allows air to pass through. This type of cooling fins not only increases the heat exchange contact area between sulfur vapor and the cooling fins, As air passes through the cooling fins, the cooling efficiency is increased.

As the material of the cooling fins, stainless steel, aluminum, or the like may be used. Among them, a particularly preferable material is stainless steel.

In the apparatus of the present invention, a pressure regulating means is disposed between the cooling means and the filtration means to eliminate the positive pressure caused by the vapor pressure of molten sulfur, which is applied when the product is transferred to the tank in the process, and the negative pressure applied when the product is shipped. It is desirable to eliminate it.

The invention will be more clearly understood from the description of the preferred embodiment with reference to the following figures.

1 is a schematic view of a structure of a sulfur recovery apparatus according to an exemplary embodiment of the present invention for removing and recovering sulfur from sulfur vapor discharged from a vent part installed on a vent part (not shown) of a molten sulfur storage tank. Is shown.

The sulfur recovery apparatus shown in FIG. 1 is located at the lower portion of the three stage cartridge type cooling means 20 and the first stage cooling means 20 for cooling the sulfur vapor, and removes sulfur vapor from the molten sulfur storage tank. Distributing means 10 for uniformly supplying the cooling means 20 of the first stage, the pressure regulating means 30 disposed on the upper portion of the third stage cooling means 20, the upper portion of the pressure regulating means 30 It is provided with a filtration means 40 and a cover 50 disposed on the upper portion of the filtration means 40.

The cartridge type cooling means 20 of each stage is detachably installed in the fixed frame 23, and each cartridge is provided with handles 22 at both ends. Therefore, the handle 22 can be pulled out, and the internal state of the cooling means can be easily checked and cleaned. The cartridge frame 23 of the cooling means is a frame for fixing the cartridge, two surfaces of which are blocked for supporting the cartridge, and two surfaces of the cooling fins in the air passage direction are perforated.

In the cartridge, the cooling fins 21 are obliquely inclined so as to be inserted and detached at regular intervals. Sulfur vapor is cooled while flowing between the cooling fin 21 and the cooling fin 21, the outside air passes through each cooling fin 21 to increase the cooling efficiency, sulfur particles are attached to the passage of the steam In order to prevent clogging, the distance between the cooling fins and the cooling fins, which are the passages of sulfur vapor, is the widest in the first stage, and the second and third stages are designed to be narrower than this. In the first and third stages, the inclination direction of the cooling fins is clockwise, and the inclination direction of the second din is counterclockwise. The inclination angle is preferably about 15 degrees.

The filtration means 40 has a structure in which the filter 43 is inserted between the upper and lower filter frames 41 and 42, and the operator checks the filter 43 from time to time and prevents the operator's face from being exposed to sulfur vapor. In order to achieve this, it is desirable to be able to attach and detach from the front of the apparatus. In addition, the weight of the filter 43 and the filter frame (41, 42) is preferably adjusted so that the filtration means 40 rises when the pressure in the device is above the set value. The set pressure depends on the design pressure of the tank. The filter 43 is coated on the surface of the filter as the molten sulfur vapor changes from solid to room temperature, resulting in a pressure loss, so that the Gore-Tex coated with a continuous porous film on the Teflon material to minimize the pressure loss. It is preferable to use such materials as the material. In general, the material of the filter is a heat-resistant polyamide fiber, such as nylon or phenolic fiber, ethylene tetrafluoride fiber, a ceramic filter, etc., the ethylene tetrafluoride filter widely known under the trade name Teflon (trade name) It is excellent in acid, alkali, water repellent, and hygroscopic. However, the Teflon filter has a disadvantage in that the pressure loss is large. Recently, in order to compensate for this, Teflon filters such as Gore-Tex and Micro-Tex, which are coated with a continuous porous membrane on the top of the Teflon material, are used. Has been developed and used.

As illustrated in detail in FIG. 2, the pressure regulating means 30 is formed on the wall of the duct 31 which is disposed on the cooling means 20 and guides the cooled steam to the filtering means 40. 40) When one or more of the hinge type hydrostatic pressure control plate 32 and the duct 31 are designed to open to the outside when the vapor pressure of the lower portion increases above the set pressure (that is, the static pressure is applied), the filtering means 40 It consists of one or more hinge type negative pressure control plates 33 which are designed to open inward when the lower vapor pressure decreases below the set pressure (ie, under negative pressure). The positive pressure control plate 32 is prepared in case that the sulfur particles are deposited on the filter and the pressure cannot be released, and the negative pressure control plate 33 is opened in order to solve the negative pressure state generated in the tank at the time of product shipment, and the air is moved inside. Inhaled to prevent damage to the tank. The negative pressure regulating plate 33 is covered with a cover 34.

The positive pressure control plate and the negative pressure control plate is preferably made of Teflon material, Figure 1 is illustrated as being installed on two sides symmetrical, two on each side as four each, of course, it may be configured differently if desired.

These pressure regulating means are prepared for the case in which the filtration means do not operate normally, and do not operate when the filter operates normally.

Cover 50 is installed on the upper portion of the filtering means 40, which is intended to protect the filtering means from rain or foreign matter, it is preferable that the operator in the form of a lid opening door so as to be convenient at the time of filter inspection or filter replacement.

In addition, the device of Figure 1 is provided with a confirmation window to facilitate the safety check. In the example shown, confirmation windows 61 and 62 are provided below the sulfur vapor distribution means 10 and under the pressure regulating means 30, respectively. In addition, after connecting the tube and the ball valve to the pipe, a ball valve is installed at the end to install a thermometer and a pressure gauge to check the inside of the tank.

This device is attached to the vent portion of the melt storage tank using a coupling means such as a flange 70, it is designed to prevent the device from shaking in the wind by using a fixing cable (80).

The effects of the present invention will become more apparent through the following examples. The present invention is not limited to the examples.

Example 1

The cartridge type cooling means according to the present invention was constructed in four stages and installed in a 6 inch vent of the molten sulfur storage tank. The size of the cooling means cartridge was 30 cm x 30 cm x 30 cm. At this time, the first stage and the second stage were arranged to be inclined seven cooling fins, and the third and fourth stages were arranged to be inclined five cooling fins. The cooling fins were made of stainless steel. The temperature was measured for each stage to confirm the cooling performance. The measurement results are shown in Table 1 below.

Comparative Example 1

The same procedure as in Example 1 was followed by installing the cooling means made of aluminum in four stages of the cooling means installed outside the cylindrical cooler body.

Height (cm) Example 1 Comparative Example 1 Other 1st stage (30) 116 ℃ 128 ℃ Exclude Spreader Height 2 steps (60) 100 ℃ 125 ℃ Exclude Spreader Height 3 steps (90) 85 ℃ 122 ℃ Exclude Spreader Height 4 steps (120) 75 ℃ 118 ℃ Exclude Spreader Height

As can be seen from Table 1, the cooler equipped with the internal cooling fin is superior in cooling efficiency to the cooler equipped with the external cooling fin, and the contact area of the cooling fin with steam is more important than the material.

Example 2

Based on the results of Example 1, the number of cartridges was determined. When the length of the cooling means using the internal cooling fins was determined that 90cm (three stages) would be sufficient. The size of the device was calculated by the capacity of the molten sulfur tank. Actually, the device to be installed in the molten sulfur storage tank was produced as shown in Figure 1 and installed in the field to confirm the performance. The cartridge was installed in a 6 inch vent with a size of 30 cm x 30 cm x 30 cm. The theoretical maximum discharge air volume of the storage tank is 1.6㎥ / min and the design safety pressure is 0.2㎏ / ㎠ · G. In order to cover this capacity, two devices with an area of 1,600 cm 2 were manufactured and installed at the rear of two 6 inch tank open vents, respectively. The filter and the filter frame were weighted to 9.9 kg to allow the filter frame to float at 0.06 kg / cm 2 · G, which is lower than the tank's reference design pressure of 0.2 kg / cm 2 · G. The sum of theoretical flow rates for these two devices is 2.0 m 3 / min. Cooling fins of the first and third stage cooler cartridges are arranged inclined clockwise, cooling fins of the second stage cooler cartridge are arranged inclined counterclockwise, and the number of cooling fins of each stage is 5 There were seven dogs, a second stage and a third stage, respectively.

The area of the pressure regulating means was made larger than that of the 6 inch vent. As a result of 15 days of field experiments, it was confirmed that sulfur vapor and particles discharged to the outside were completely removed. However, since a small amount of sulfur particles may be deposited in the field-installed filter, data on aeration rate of the filter according to the use is required, which is an important data for determining the life of the filter.

In order to obtain such data, experiments for evaluating the air permeability of the new filter and the filter of the device operated in the field for 15 days were conducted. In the experiment, the pressure and the flow rate applied to the filter surface were measured and compared with the filter flow rate of the air.

Pressure (㎏ / ㎠ · G) Sectional area (㎡) Filter after 15 days of use New filter Primary Secondary 3rd Average Passing flow rate Primary Secondary 3rd Average Passing flow rate ℓ / min ℓ / min 0.01 0.0095 22 20 22 21 0.04 36 30 30 32 0.06 0.03 0.0095 38 36 40 38 0.07 52 47 50 50 0.09 0.05 0.0095 54 54 55 54 0.10 62 63 65 63 0.11 0.07 0.0095 68 64 66 66 0.12 75 73 75 74 0.13 0.09 0.0095 78 74 77 76 0.13 84 80 82 82 0.14 0.10 0.0095 82 78 80 80 0.14 90 87 87 88 0.15

As can be seen from Table 2, in the case of 0.01 kg / cm 2 · G, which is very low in pressure, the aeration rate is 0.04 m / sec and 0.06 m / sec, but the difference is large. When the ratio is equal to or greater than 0.05 kg / cm 2 · G of ¼ of cm 2 · G), no difference is seen, and thus, the tank may have a capacity as much as the amount of the tank discharge air at an operating pressure of 0.06 kg / cm 2 · G or less.

This is thought to be due to the low pressure loss of the coated continuous porous (Gortex filter) filter, although the cooler cools the sulfur vapor sufficiently to convert it into solid particles and some sulfur vapor is deposited in the filter which does not turn completely solid.

As a result of the above experiment, the sulfur recovery device by the cooling means with the internal cooling fin and the porous filter is a device capable of sufficiently converting the sulfur vapor discharged to the outside without affecting the safe operation of the molten sulfur tank to change into particles and recover it. It was confirmed that.

According to the present invention, the sulfur vapor generated in the molten sulfur storage tank is sufficiently cooled by the cooling means equipped with the internal cooling fins to improve the cooling performance, the life of the filter increases due to the use of a porous filter, sulfur vapor removal And sulfur particle recovery efficiency. In addition, since the cooler and the filter are cartridge type, it is easy to check and clean the sulfur particles deposited in the cooler, and to inspect the filter.

Claims (9)

In the device for recovering sulfur from the sulfur vapor discharged from the vent of the molten sulfur storage tank, The apparatus comprises one or two or more cartridge type cooling means (20) for cooling sulfur vapor and filtration means (40) located on top of the cooling means (20); The cooling means 20 is a sulfur recovery device, characterized in that the plurality of cooling fins 21 is a cartridge-type cooling means detachably inserted into the cartridge at regular intervals. 2. The sulfur recovery apparatus of claim 1, wherein the cooling fins 21 are disposed obliquely inclined to the cartridge type cooling means 20. In claim 1 or 2, the cooling means 20 is installed in two or more stages, each cooling means is installed detachably to the fixed frame 23, the inclined direction of the cooling fins 21 of each stage is the same or Or another sulfur recovery device. The sulfur recovery apparatus according to claim 1 or 2, wherein the number of cooling fins (21) in the cooling means (20) is 5 to 7. In claim 3, sulfur recovery device, characterized in that the interval between the arrangement of the cooling fins 21 of the lowest cooling means (20) is relatively wide. In claim 1, the filtering means 40 has a structure in which the filter 43 is inserted between the upper and lower filter frames 41 and 42, and the weight of the filter 43 and the filter frames 41 and 42 is internal to the apparatus. Sulfur recovery device, characterized in that the filter means 40 is adjusted to rise if the pressure of the above the set value. The sulfur recovery apparatus of claim 6, wherein the filter 43 is coated with a continuous porous membrane on a Teflon material. In claim 1, a pressure regulating means 30 is disposed between the cooling means 20 and the filtering means 40, the pressure adjusting means 30 is a duct 31 for guiding the cooled steam to the filtering means 40. Is formed on the wall of the filter means 40 is formed on the wall surface of the one or two hinge type hydrostatic pressure control plate 32 and the duct 31 designed to open to the outside when the vapor pressure of the filter means 40 increases above the set pressure (filter means ( 40) A sulfur recovery device, comprising: a pressure regulating means (30) having one or more hinge type negative pressure regulating plates (33) designed to open inward when the vapor pressure of the lower portion decreases below a set pressure. The sulfur recovery device, characterized in that sulfur vapor distribution means is installed in the lower portion of the cooling means (20).