Device for recycling MTBE1-butene byproduct isobutane

Abstract

The utility model discloses a device for recycling MTBE (methyl tert-butyl ether) 1-butene byproduct isobutane, which comprises a rectification unit, an MTBE raw material tank and an isobutane product tank, and the rectification unit is respectively connected with the MTBE raw material tank and the isobutane product tank. By using the device, after passing through the rectification unit, one part of the mixed isobutane product with oxygen-containing compounds removed returns to the MTBE raw material tank, and the other part of the isobutane product is sold as the isobutane product, so that the economic benefit of the device is improved. By means of the device, the content of oxygen-containing compounds in the MTBE1-butene byproduct isobutane is reduced to below 10 ppm, and the isobutane recycling of the device is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of chemical industry, concretely relates to a device for recycling MTBE 1-butene byproduct isobutane. BACKGROUND

[0002] The isobutene concentration in the upstream raw material of the MTBE 1-butene device is relatively high (the concentration is about 50%), the isobutene in the raw material carbon four reacts with methanol under the action of a macroporous strong acid cation exchange resin catalyst to generate etherification, the reaction is a reversible equilibrium exothermic reaction, but the relatively high isobutene concentration can make the reactor bed temperature rise too high (rise by 6-10 DEG C), and the side reactions increase. The main side reactions are that the isobutene self-polymerizes to form a dimer, the isobutene reacts with water to generate tertiary butyl alcohol, and the methanol condensation reaction generates dimethyl ether, which leads to unqualified MTBE purity. In order to maintain the stability of the temperature, the traditional solution is to use part of the isobutane purchased or introduced from other devices, mix the isobutane with the raw material, dilute the isobutene concentration, and control the isobutane concentration to be about 50%. Although the isobutane itself does not participate in the reaction, it can mix with the MTBE side reaction products and leave the device, and the mixed isobutane contains a relatively high content (2500ppm to 3500ppm) of oxygen-containing compounds (mainly dimethyl ether), and can only be sent to the downstream device as ordinary liquefied gas. SUMMARY

[0003] In order to solve the problem of recycling and reusing the isobutane byproduct of the MTBE 1-butene device, the utility model provides a device for recycling and reusing the isobutane byproduct of the MTBE 1-butene device. After the device is used, the mixed isobutane product removes part of the oxygen-containing compounds and returns to the MTBE raw material tank, and the other part is sold as an isobutane product, which improves the economic benefit of the device.

[0004] The purpose of the application is achieved by the following technical solutions:

[0005] A device for recycling and reusing the isobutane byproduct of the MTBE 1-butene device, comprising a rectification unit, an MTBE raw material tank and an isobutane product tank, wherein the rectification unit is connected with the MTBE raw material tank and the isobutane product tank respectively.

[0006] Further, the rectification unit comprises a rectification tower, a tower bottom reboiler, a tower top cooler and a product cooler, the tower bottom reboiler is located at the bottom of the rectification tower, the tower top cooler is located at the top of the rectification tower, the tower top cooler is connected with a reflux tank, the reflux tank is connected with the top of the rectification tower, and the bottom of the rectification tower is connected with the product cooler.

[0007] Further, a reflux pump is arranged between the reflux tank and the tower top cooler.

[0008] Further, the reflux pump is provided with an adjusting valve I between the reflux pump and the rectifying tower, and the adjusting valve is used to control the reflux of the rectifying tower.

[0009] Further, the top of the reflux tank is connected with a fuel gas pipe network.

[0010] Further, the top of the reflux tank is provided with an adjusting valve II, and the light components (containing oxygen compounds (mainly dimethyl ether) and trace propane) on the top of the reflux tank are discharged to the fuel gas pipe network through the adjusting valve II.

[0011] Further, the product cooler is provided with an adjusting valve III between the product cooler and the MTBE raw material tank, and the adjusting valve is used to control the amount of isobutane recovered.

[0012] A method for recycling isobutane byproduct of MTBE1-butene, using the device for recycling isobutane byproduct of MTBE1-butene, the method comprises the following steps:

[0013] (1) The MTBE1-butene byproduct isobutane containing oxygen compounds is distilled through a rectifying unit to obtain a treated isobutane product; wherein, the byproduct containing oxygen compounds is the byproduct of isobutane and MTBE;

[0014] (2) The treated isobutane product is returned to the MTBE raw material tank and / or the isobutane product tank.

[0015] Further, the method specifically comprises:

[0016] (1) The MTBE1-butene byproduct isobutane containing oxygen compounds is sent to the rectifying tower, the light components on the top of the tower are cooled by the tower top cooler after being heated by the tower bottom reboiler, and then are returned to the reflux tank in full reflux.

[0017] (2) The isobutane product at the bottom of the rectifying tower is sent to the product cooler under self-pressure, and a part of the isobutane product is returned to the MTBE raw material tank, and the other part of the isobutane product is sent to the isobutane product tank.

[0018] Further, the isobutane in the MTBE raw material tank is used to dilute the isobutene concentration in the MTBE1-butene device; and the isobutane in the isobutane product tank is sold as a product.

[0019] Further, the light components (containing oxygen compounds (mainly dimethyl ether) and trace propane) on the top of the reflux tank are discharged to the fuel gas pipe network.

[0020] Further, the bottom temperature of the rectifying tower is controlled at 60-80℃, the top temperature of the rectifying tower is controlled at 40-60℃, the pressure of the rectifying tower is controlled at 0.65-1.0 MPa (G), and the temperature of the tower top cooler is controlled at 35-50℃.

[0021] Further, the product cooling temperature is controlled at 35-40℃.

[0022] Further, the oxygen-containing compound (mainly dimethyl ether) in the MTBE 1-butene byproduct isobutane is about 2500-3500 ppm, and the oxygen-containing compound is removed from the isobutane after the rectification, so that the content of the oxygen-containing compound (mainly dimethyl ether) in the treated isobutane product is reduced to below 10 ppm.

[0023] The utility model has the advantages of:

[0024] The use of the device, after the rectification unit, the mixed isobutane product removes the oxygen-containing compound part returns to the MTBE raw material tank, the other part is sold as isobutane product, improves the economic benefit of the device.

[0025] Through the device, the oxygen-containing compound in the MTBE 1-butene byproduct isobutane is reduced to below 10 ppm, the isobutane in the device is recycled, the isobutane in the MTBE raw material tank is reduced from other ways, in addition, the product quality of isobutane is improved, and the economic benefit of the device is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic diagram of the device for recycling the MTBE 1-butene byproduct isobutane.

[0027] Among them, 1, rectification tower, 2, tower bottom reboiler, 3, tower top cooler, 4, reflux tank, 5, reflux pump, 6, product cooler, 7, regulating valve I, 8, regulating valve II, 9, regulating valve III. DETAILED DESCRIPTION

[0028] The following non-limiting examples can make those skilled in the art more fully understand the utility model, but do not limit the utility model in any way.

[0029] Example 1

[0030] The application relates to a device for recycling MTBE 1-butene byproduct isobutane, which comprises a rectification unit, an MTBE raw material tank and an isobutane product tank, wherein the rectification unit is connected with the MTBE raw material tank and the isobutane product tank respectively.

[0031] Embodiment 2

[0032] The application relates to a method for recycling MTBE 1-butene byproduct isobutane, which uses the device for recycling MTBE 1-butene byproduct isobutane in the embodiment 1 and comprises the following steps.

[0033] The MTBE 1-butene byproduct isobutane containing oxygen compounds is sent to the rectification tower 1, the top light components are cooled by the tower top cooler 3 after being heated by the tower bottom reboiler 2 and then enter the reflux tank 4, the light components (mainly dimethyl ether and trace amount of propane) at the top of the reflux tank 4 are discharged to the fuel gas pipe network through the adjusting valve II 7, the isobutane at the bottom of the reflux tank 4 is totally refluxed into the rectification tower 1 through the reflux pump 5, the isobutane product at the bottom of the rectification tower 1 is cooled by the product cooler 6, a part of the isobutane product is returned to the MTBE raw material tank, and the other part is sent to the isobutane product tank, the bottom temperature of the rectification tower 1 is controlled to be 65 DEG C, the top temperature is controlled to be 45 DEG C, the top pressure is controlled to be 0.8 MPa (G), and the top cooling temperature is controlled to be 35 DEG C, and the product cooling temperature is controlled to be 30 DEG C.

[0034] The data comparison before and after the treatment of the MTBE 1-butene byproduct containing oxygen compounds is shown in the following table.

[0035] Table 1 analysis result of the untreated isobutane byproduct

[0036]

[0037]

[0038] Table 2 analysis result of the isobutane byproduct after the treatment of the application

[0039]

[0040] The oxygenate content (mainly dimethyl ether) in the MTBE 1-butene by-product isobutane, which contains oxygenate, is about 2500 ppm to 3500 ppm, and after this rectification, the oxygenate is removed from the isobutane, and the oxygenate content (mainly dimethyl ether) in the treated isobutane product is reduced to less than 10 ppm.

Claims

1. A device for recovering and utilizing isobutane, a byproduct of MTBE1-butene, characterized in that, include: The distillation unit is connected to the MTBE feed tank and the isobutane product tank, respectively. The distillation unit includes a distillation column, a bottom reboiler, a top cooler, and a product cooler. The bottom reboiler is located at the bottom of the distillation column, and the top cooler is located at the top of the distillation column. The top cooler is connected to a reflux tank, and the reflux tank is connected to the top of the distillation column. The bottom of the distillation column is connected to the product cooler.

2. The apparatus according to claim 1, characterized in that, A reflux pump is provided between the reflux tank and the top cooler.

3. The apparatus according to claim 1, characterized in that, The top of the reflux tank is connected to the fuel gas pipeline network.

4. The apparatus according to claim 2, characterized in that, A regulating valve I is provided between the reflux pump and the distillation column.

5. The apparatus according to claim 1, characterized in that, The top of the reflux tank is equipped with a regulating valve II.

6. The apparatus according to claim 1, characterized in that, A regulating valve III is provided between the product cooler and the MTBE raw material tank.

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