Device for treating non-condensable gas at top of vacuum tower

Abstract

The utility model provides a vacuum tower top non-condensable gas treatment device which comprises a vacuum tower used for providing raw materials; the water cooler is used for condensing the oil gas fractionated by the vacuum tower; the large gas tank is used for collecting oil gas and non-condensable gas condensed by the water cooler; the circulating vacuum pump is used for collecting and compressing the non-condensable gas of the water cooler; wherein the top of the large gas tank is provided with a first pipeline, one end of the first pipeline is connected with a second pipeline, the second pipeline is respectively communicated with a torch and an air blower of a heating furnace, and the torch and the air blower in the heating furnace are respectively connected with a stop valve. According to the utility model, when the concentration of combustible gas exceeds a safety threshold value, the system can automatically take measures to safely discharge dangerous gas to a torch system for combustion, so that possible explosion or fire disasters are prevented, meanwhile, the economical efficiency is high, the occupied investment is smaller, and the safety is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a pressure reducing tower top noncondensable gas treatment device. BACKGROUND

[0002] In order to deeply pull out the product of heavy component in petrochemical unit, the oil product needs to be heated to bubble point temperature, and too high temperature is easy to make the oil product crack even coking, in order to reduce the bubble point temperature of heavy component, the pressure reducing tower is usually used to pull out the vacuum gas oil, the method for keeping a certain vacuum degree of the pressure reducing tower includes steam jet pump, liquid ring vacuum pump, combined vacuum extraction and other methods, the pressure reducing tower top oil gas component and water gas are separated by condensation, and the remaining noncondensable gas is discharged.

[0003] At present, the noncondensable gas treatment in the existing hydrogenation device has the following methods:

[0004] (1) the noncondensable gas is directly discharged to the atmosphere, which pollutes the environment and does not meet the environmental protection requirements, and also causes material waste;

[0005] (2) when the torch pressure fluctuates, it may cause large emission resistance and pressure accumulation of the pressure reducing tower top air tank, and secondly, the current regulation stipulates that the torch combustion device cannot be used as a daily air pollution treatment facility;

[0006] (3) a gas tank recovery system is arranged, the noncondensable gas is recovered to the gas tank, then pressurized and used as furnace fuel gas, the noncondensable gas amount of the pressure reducing tower top is very small, and this method has large land occupation and investment and complex operation;

[0007] (4) the RTO (regenerative thermal oxidation furnace) technology is used to recover the noncondensable gas, the waste gas is heated to above 760 DEG C, so that the VOC component in the waste gas is oxidized and decomposed into carbon dioxide, and the disadvantages of this technology are large investment and land occupation, large fuel consumption, small noncondensable gas amount and low VOC content, and the technology is not economical;

[0008] (5) the condensation+adsorption method oil gas recovery treatment device is used to treat the noncondensable gas, the noncondensable gas is deeply cooled to make most of the oil gas become liquid and be recovered, the remaining air is discharged after the remaining hydrocarbons in the uncondensed gas are adsorbed by the adsorption tank, and this technology has large investment and land occupation, and complex process for treating small noncondensable gas of the pressure reducing tower top.

[0009] The above-mentioned several methods all have some defects, therefore, under the condition of not setting a pressurizing device, the noncondensable gas is sent to the hearth of the heating furnace, and a combustible gas on-line monitoring instrument is arranged, so as to prevent the combustible gas from entering the hearth, and the pressure reducing tower top noncondensable gas treatment device has high economy, small land occupation and investment and guaranteed safety. UTILITY MODEL CONTENTS

[0010] The utility model provides a pressure reducing tower top noncondensable gas treatment device, and can effectively solve the above-mentioned problems.

[0011] The utility model discloses a device for treating non-condensable gas at the top of a vacuum tower.

[0012] The device for treating non-condensable gas at the top of a vacuum tower comprises

[0013] A vacuum tower for providing raw materials;

[0014] A water cooler for condensing oil gas fractionated from the vacuum tower;

[0015] An atmospheric tank for collecting the oil gas and non-condensable gas condensed by the water cooler;

[0016] A circulating vacuum pump for compressing the non-condensable gas of the water cooler;

[0017] The atmospheric tank is provided with a first pipeline at the top, one end of the first pipeline is connected with a second pipeline, the second pipeline is in communication with a blower of a flare and a heating furnace respectively, and the blower of the flare and the heating furnace is respectively connected with a shut-off valve.

[0018] As a further improvement, the second pipeline comprises an A pipeline and a B pipeline, the A pipeline and the B pipeline are respectively connected with the blowers of the flare and the heating furnace for classified delivery of the non-condensable gas.

[0019] As a further improvement, an online analyzer is arranged on the pipeline to the blower of the heating furnace, when the concentration of combustible gas exceeds a safety threshold, the system can automatically discharge the dangerous gas to the flare system for combustion through the A pipeline.

[0020] As a further improvement, the vacuum tower is further connected with a control instrument.

[0021] As a further improvement, the control instrument is connected in series with the circulating vacuum pump, the circulating vacuum pump is connected with a control valve, and the control valve is controlled by the control instrument to realize stable pressure.

[0022] The utility model discloses a device for treating non-condensable gas at the top of a vacuum tower.

[0023] (1) the utility model discloses a two-way discharge direction is set, and the system can discharge non-condensable gas to the blower inlet pipeline when normal operation, and when detecting that the combustible gas component content exceeds the set value, can automatically close the pipeline to the blower and open the shut-off valve to the flare, thereby avoiding the combustible gas into the blower system to cause potential safety risk, and the online combustible gas detection device can monitor the gas component content in real time, and once detecting the anomaly, the system will automatically respond, and this automatic control mechanism improves the response speed and safety of the system, simultaneously, the utility model discloses new equipment is less, and the investment is small, and the land occupation is small, and the process is simple, and the operation is convenient, and does not cause environmental pollution. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a flowchart of the non-condensable gas treatment process of this utility model.

[0026] Explanation of icon numbers:

[0027] 1. Pressure reducing tower; 2. Water cooler; 3. Atmosphere tank; 4. Circulating vacuum pump; 5. Flare; 6. Blower; 7. Online analyzer; 8. Heating furnace; 9. Control instruments. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely to represent selected embodiments of this utility model.

[0029] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0030] Reference Figure 1 As shown, the non-condensable gas treatment device at the top of the pressure reducing tower includes a pressure reducing tower 1 for providing raw materials; a water cooler 2 for condensing the oil and gas fractionated from the pressure reducing tower 1; an atmospheric tank 3 for collecting the oil and gas and non-condensable gas condensed by the water cooler 2; and a circulating vacuum pump 4 for collecting and compressing the non-condensable gas collected from the water cooler 2.

[0031] The top of the atmosphere tank 3 is provided with a first pipeline, one end of the first pipeline is connected with a second pipeline, the second pipeline is communicated with the torch 5 and the blower 6 of the heating furnace 8 respectively, and the blower 6 in the torch 5 and the heating furnace 8 is respectively connected with a cut-off valve.

[0032] The pipeline to the blower 6 in the heating furnace 8 is provided with an online analyzer 7, when the combustible gas concentration exceeds the safety threshold value, the system can automatically discharge the dangerous gas to the torch 5 system for combustion.

[0033] The online analyzer 7, such as SOLAREx series LEL concentration analyzer, adopts hydrogen flame ionization detector (FID) and hydrogen flame temperature detector (FTA) technology, can monitor the combustible gas concentration in the exhaust gas in real time, the FID detector measures the organic matter content in the sample by hydrogen flame ionization, directly measures the organic matter content in the sample, and the LEL value corresponding to the explosion limit of the corresponding component, and the FTA directly measures the inorganic matter, ensures the measurement accuracy and linearity, the response time of such analyzer is extremely fast, less than 1 second, can timely detect the change of the combustible gas component content, so that when the online analyzer 7 monitors that the combustible gas component content exceeds the set value in the pressure reducing tower 1 process, a signal is automatically sent to the automatic cut-off valve, the signal causes the automatic cut-off valve to close the cut-off valve of the pipeline connected to the pressure reducing tower 1, and opens the cut-off valve to the torch 5 system at the same time, compared with the existing processing method, such linkage mechanism ensures that when the combustible gas concentration exceeds the safety threshold value, the system can automatically take measures to safely discharge the dangerous gas to the torch 5 system for combustion, so as to prevent possible explosion or fire, at the same time, the economy is high, the land investment is small, and the safety is guaranteed.

[0034] The second pipeline includes an A pipeline and a B pipeline, the A pipeline and the B pipeline are connected with the blower 6 in the torch 5 and the heating furnace 8 respectively, for classified conveying of the non-condensable gas, which is beneficial to transmit the combustible gas component in the non-condensable gas to the torch 8 through the A pipeline.

[0035] The pressure reducing tower 1 is also connected with a control instrument 9; the control instrument 9 is connected with the circulating vacuum pump 4 in series, the circulating vacuum pump 4 is connected with a control valve, and the control valve is controlled by the control instrument 9 to realize the stability of the pressure.

[0036] The case also includes a pressure reducing tower top non-condensable gas treatment device treatment process:

[0037] S1, raw material feeding:

[0038] The raw oil is sent into the system by a feeding pump (not shown in the figure), and is ready to enter the pressure reducing tower 1;

[0039] S2, Heating process:

[0040] The raw oil is heated by a heating furnace (not shown in the figure) before entering the vacuum tower 1 to increase the temperature and reduce the viscosity, preparing for fractionation;

[0041] S3, Vacuum fractionation:

[0042] The heated raw oil enters the vacuum tower 1 and is fractionated under reduced pressure. The pressure inside the vacuum tower 1 is lower than atmospheric pressure, which can lower the boiling point of each component in the oil product, allowing separation at a lower temperature and reducing the risk of thermal cracking;

[0043] S4, Oil gas cooling:

[0044] After the fractionated oil gas mixture comes out of the top of the vacuum tower 1, it enters the water cooler 2 for cooling, reducing the temperature of the oil gas mixture through the cooling effect of water, preparing for subsequent processing;

[0045] S5, Side line extraction (process not shown in the figure):

[0046] According to needs, specific fraction products are extracted from the side line tower (not shown in the figure) of the vacuum tower 1, or further fractionation is carried out;

[0047] S6, Non-condensable gas treatment:

[0048] Non-condensable gases produced during fractionation are collected and sent to the flare 5 or other treatment facilities;

[0049] S7, Vacuum maintenance:

[0050] The liquid ring vacuum pump 4 works to maintain the required vacuum state of the vacuum tower 1, ensuring the efficiency of fractionation;

[0051] S8, Gas analysis:

[0052] The online analyzer 7 monitors and analyzes the changes in the content of combustible gas components in real time, ensuring that the product meets the predetermined quality standards;

[0053] S9, Pressure regulation:

[0054] Controlled by return line regulating valve;

[0055] S10, Combustion system:

[0056] Non-condensable gases are burned by the flare 5, which is a safe discharge method for handling harmful or flammable gases;

[0057] S11, Safe discharge:

[0058] The flare 5 (cannon) system is used to safely burn and discharge gases that are not suitable for recycling;

[0059] S12, heating furnace combustion:

[0060] The heating furnace 8 burns non-condensable gas without explosive components.

[0061] The whole process is a continuous physical separation and treatment process, which separates different components in the raw oil into valuable products by accurately controlling pressure, temperature and flow, and ensures stable operation of the whole system and environmental safety.

[0062] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and the present application can be variously changed and modified for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A non-condensable gas treatment device for the top of a pressure reducing tower, characterized in that, The device includes Pressure reducing tower (1), used to provide raw materials; Water cooler (2) is used to condense the oil and gas fractionated from the pressure reducing tower (1); Atmospheric tank (3) is used to collect the oil and non-condensable gases condensed by the water cooler (2); A circulating vacuum pump (4) is used to collect and compress the non-condensable gas from the water cooler (2); The top of the atmospheric tank (3) is provided with a first pipe, one end of which is connected to a second pipe. The second pipe is connected to the blowers (6) of the torch (5) and the heating furnace (8), respectively. The blowers (6) in the torch (5) and the heating furnace (8) are respectively connected to shut-off valves.

2. The non-condensable gas treatment device at the top of the pressure reducing tower according to claim 1, characterized in that, The second pipeline includes pipeline A and pipeline B, which are respectively connected to the blower (6) in the flare (5) and the heating furnace (8) for classifying and transporting the non-condensable gas.

3. The non-condensable gas treatment device at the top of the pressure reducing tower according to claim 2, characterized in that, An online analyzer (7) is installed on the pipe of the blower (6) in the heating furnace (8). When the concentration of combustible gas exceeds the safety threshold, the system can automatically discharge the dangerous gas safely through the A pipe to the flare (5) system for combustion.

4. The non-condensable gas treatment device at the top of the pressure reducing tower according to claim 1, characterized in that, The pressure reducing tower (1) is also connected to a control instrument (9).

5. The non-condensable gas treatment device at the top of the pressure reducing tower according to claim 4, characterized in that, The control instrument (9) is connected in series with the circulating vacuum pump (4), and the circulating vacuum pump (4) is connected to a control valve. The control valve is controlled by the control instrument (9) to achieve pressure stabilization.

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