An apparatus for high value utilization of isobutane

Abstract

The utility model relates to a device of high -value utilization isobutane, the device includes isobutane dehydrogenation unit, MTBE unit, removes dimethyl ether unit, this device sends to MTBE unit production MTBE after isobutane dehydrogenation, and removes dimethyl ether in the carbon four after ether through the dimethyl ether unit, and returns as isobutane dehydrogenation raw material, can almost digest isobutane in raw material completely, realizes high -value utilization of isobutane, reduces production cost, improves economic benefits.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, and more specifically, to an apparatus for high-value utilization of isobutane. Background Technology

[0002] In the C4 processing industry chain, butene and isobutane were originally used for alkylation reactions to produce isooctane, a high-octane gasoline component. However, with the implementation of the isooctane consumption tax, traditional isooctane plants are no longer profitable. MTBE, as a gasoline additive with excellent anti-knock properties, good miscibility with gasoline, and no environmental pollution, has seen continuous growth in market demand in recent years. Currently, most C4 feedstocks on the market are mixtures of butane and butene. In the original industry chain, butene could be used to produce MTBE or sec-butyl acetate, but a large amount of isobutane remained unused and could only be sold as liquefied petroleum gas, resulting in very low or even negative economic benefits.

[0003] Isobutane dehydrogenation technology uses isobutane as a raw material, cracking it to produce isobutene and hydrogen. The generated isobutene can be used as a feedstock for MTBE (Metal-to-Beform ester). The MTBE reaction can achieve an isobutene conversion rate of 99.85%. The isobutane content in the C4 ester after etherification in MTBE units is very high, making it an ideal feedstock for isobutane dehydrogenation. However, the C4 ester contains approximately 1400 ppm of dimethyl ether (an oxygen-containing compound), while the feedstock for isobutane dehydrogenation generally requires an oxygen content (based on water) of ≤350 ppm. Therefore, the C4 ester cannot be directly used as a feedstock for isobutane dehydrogenation. Thus, improvements to the existing technology are needed to increase the utilization rate of isobutane and reduce production costs. Utility Model Content

[0004] This invention provides a device for high-value utilization of isobutane. Through structural optimization design, isobutane is dehydrogenated and sent to the MTBE unit to produce MTBE. After the dimethyl ether removal unit removes the dimethyl ether from the C4 ether, it is returned as a raw material for isobutane dehydrogenation. This method can almost completely digest the isobutane in the raw material, realize the high-value utilization of isobutane, reduce production costs, and improve economic benefits.

[0005] This invention provides an apparatus for high-value utilization of isobutane, the apparatus comprising an isobutane dehydrogenation unit, an MTBE unit, and a dimethyl ether removal unit; one outlet of the isobutane dehydrogenation unit is connected to the inlet of the MTBE unit, the outlet of the MTBE unit is connected to the inlet of the dimethyl ether removal unit, and the outlet of the dimethyl ether removal unit is connected to the inlet of the isobutane dehydrogenation unit.

[0006] When the device is in use, the isobutane feedstock enters the isobutane dehydrogenation unit for dehydrogenation to obtain dehydrogenated C4 and hydrogen-rich tail gas. The dehydrogenated C4 enters the MTBE unit, where it reacts with methanol to obtain MTBE and post-etherified C4. The post-etherified C4 then enters the dimethyl ether removal unit to remove dimethyl ether. The post-etherified C4 after dimethyl ether removal is returned to the isobutane dehydrogenation unit for reuse as feedstock.

[0007] Furthermore, the device also includes a PSA unit, with another outlet of the isobutane dehydrogenation unit connected to the inlet of the PSA unit.

[0008] In the above technical solution, by setting up a PSA unit in the device and connecting another outlet of the isobutane dehydrogenation unit to the inlet of the PSA unit, the hydrogen-rich tail gas produced by the isobutane dehydrogenation unit enters the PSA unit and produces hydrogen, thereby realizing the recovery and utilization of hydrogen.

[0009] Further, the dimethyl ether removal unit includes a post-ether C4 buffer tank, an inlet / outlet heat exchanger, a dimethyl ether removal tower, an air cooler, a reflux tank, a light component condenser, a light component buffer tank, and an outlet cooler. The inlet of the post-ether C4 buffer tank is connected to the outlet of the MTBE unit. The outlet of the post-ether C4 buffer tank is connected to the upper inlet of the dimethyl ether removal tower via a pipeline through the inlet / outlet heat exchanger. The top outlet of the dimethyl ether removal tower is connected to the inlet of the reflux tank via a pipeline through the air cooler. The top outlet of the reflux tank is connected to the inlet of the light component buffer tank via a pipeline through the light component condenser. The outlet of the light component buffer tank is connected to the tank area via a pipeline. The bottom outlet of the reflux tank is connected to the top inlet of the dimethyl ether removal tower via a pipeline. The bottom outlet of the dimethyl ether removal tower is connected to the inlet of the isobutane dehydrogenation unit via a pipeline, sequentially through the inlet / outlet heat exchanger and the outlet cooler.

[0010] When dimethyl ether (DME) is removed using the DME removal unit, the post-ether C4 from the MTBE unit enters the post-ether C4 buffer tank and is preheated by the feed heat exchanger before being sent to the DME removal tower for distillation. DME, C3, and some C4 are distilled from the top of the tower, cooled by the air cooler, and then enter the reflux tank. The condensed liquid phase is sent to the DME removal tower for reflux. The uncondensed DME, C3, and other light components are condensed into liquid phase again by the light component condenser and then enter the light component buffer tank and are sent to the tank area. The post-ether C4 collected from the bottom of the DME tower after DME removal is cooled by the feed heat exchanger and the outlet cooler and then returned to the isobutane dehydrogenation unit as raw material for reuse.

[0011] Furthermore, a booster pump is installed on the pipeline between the post-ether C4 buffer tank and the dimethyl ether removal tower.

[0012] In the above technical solution, by installing a booster pump on the pipeline between the post-ether C4 buffer tank and the dimethyl ether stripper, a stable and sufficient pressure feed can be provided to the dimethyl ether stripper, ensuring the efficient operation of the distillation process.

[0013] Furthermore, a light component extraction pump is installed on the pipeline between the light component buffer tank and the tank area.

[0014] In the above technical solution, by installing a light component extraction pump on the pipeline between the light component buffer tank and the tank area, the light component liquid in the buffer tank can be stably transported to the tank area for storage.

[0015] Furthermore, a reflux pump is installed on the pipeline between the bottom outlet of the reflux tank and the top inlet of the dimethyl ether removal tower.

[0016] In the above technical solution, by installing a reflux pump on the pipeline between the bottom outlet of the reflux tank and the top inlet of the dimethyl ether removal tower, the stable operation and efficient separation of the dimethyl ether removal tower can be guaranteed.

[0017] The beneficial effects of this utility model are as follows: The device for high-value utilization of isobutane of this utility model, through structural optimization design, sends isobutane to the MTBE unit for MTBE production after dehydrogenation, and removes dimethyl ether from the C4 after etherification through the dimethyl ether removal unit, and returns it as a raw material for isobutane dehydrogenation. It can almost completely digest the isobutane in the raw material, realize the high-value utilization of isobutane, reduce production costs, and improve economic benefits. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the device for high-value utilization of isobutane according to this utility model; Figure 2 This is a schematic diagram of the dimethyl ether removal device in this utility model; The components include: 1. Post-etherification C4 buffer tank; 2. Feed and discharge heat exchanger; 3. Dimethyl ether removal tower; 4. Air cooler; 5. Reflux tank; 6. Light component condenser; 7. Light component buffer tank; 8. Discharge cooler; 9. Booster pump; 10. Light component extraction pump; and 11. Reflux pump. Detailed Implementation

[0020] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0021] Please refer to Figure 1-2 The present invention relates to a high-value utilization device for isobutane, the device comprising an isobutane dehydrogenation unit, an MTBE unit, and a dimethyl ether removal unit; one outlet of the isobutane dehydrogenation unit is connected to the inlet of the MTBE unit, the outlet of the MTBE unit is connected to the inlet of the dimethyl ether removal unit, and the outlet of the dimethyl ether removal unit is connected to the inlet of the isobutane dehydrogenation unit.

[0022] The butane dehydrogenation unit can use an existing butane dehydrogenation device, and the MTBE unit can use an existing MTBE device, but are not limited to these.

[0023] When the device is in use, the isobutane feedstock enters the isobutane dehydrogenation unit for dehydrogenation to obtain dehydrogenated C4 and hydrogen-rich tail gas. The dehydrogenated C4 enters the MTBE unit, where it reacts with methanol to obtain MTBE and post-etherified C4. The post-etherified C4 then enters the dimethyl ether removal unit to remove dimethyl ether. The post-etherified C4 after dimethyl ether removal is returned to the isobutane dehydrogenation unit for reuse as feedstock.

[0024] This invention relates to a device for high-value utilization of isobutane. After dehydrogenation, isobutane is sent to the MTBE unit to produce MTBE. The device then removes dimethyl ether from the C4 carbon after etherification in the dimethyl ether removal unit and returns it as a raw material for isobutane dehydrogenation. This process almost completely digests the isobutane in the raw material, achieving high-value utilization of isobutane, reducing production costs, and improving economic efficiency.

[0025] Furthermore, such as Figure 1 As shown, the device also includes a PSA unit, and another outlet of the isobutane dehydrogenation unit is connected to the inlet of the PSA unit.

[0026] The PSA unit can use existing PSA devices, but is not limited to them.

[0027] In the above technical solution, by setting up a PSA unit in the device and connecting another outlet of the isobutane dehydrogenation unit to the inlet of the PSA unit, the hydrogen-rich tail gas produced by the isobutane dehydrogenation unit enters the PSA unit and produces hydrogen, thereby realizing the recovery and utilization of hydrogen.

[0028] Furthermore, such as Figure 2As shown, the dimethyl ether removal unit includes a post-etherification C4 buffer tank 1, an inlet / outlet heat exchanger 2, a dimethyl ether removal tower 3, an air cooler 4, a reflux tank 5, a light component condenser 6, a light component buffer tank 7, and an outlet cooler 8. The inlet of the post-etherification C4 buffer tank 1 is connected to the outlet of the MTBE unit, and the outlet of the post-etherification C4 buffer tank 1 is connected to the upper inlet of the dimethyl ether removal tower 3 via a pipeline through the inlet / outlet heat exchanger 2. The top outlet of the dimethyl ether removal tower 3 is connected via... The pipeline is connected to the inlet of the reflux tank 5 via the air cooler 4. The top outlet of the reflux tank 5 is connected to the inlet of the light component buffer tank 7 via the light component condenser 6 via a pipeline. The outlet of the light component buffer tank 7 is connected to the tank area via a pipeline. The bottom outlet of the reflux tank 5 is connected to the top feed port of the dimethyl ether removal tower 3 via a pipeline. The bottom outlet of the dimethyl ether removal tower 3 is connected to the inlet of the isobutane dehydrogenation unit via the feed heat exchanger 2 and the discharge cooler 8 via a pipeline.

[0029] When dimethyl ether (DME) is removed using the DME removal unit, the post-ether C4 from the MTBE unit enters the post-ether C4 buffer tank 1 and is preheated by the feed heat exchanger 2 before being sent to the DME removal tower 3 for distillation. DME, C3, and some C4 are distilled from the top of the tower, cooled by the air cooler 4, and then enter the reflux tank 5. The condensed liquid phase is sent to the DME removal tower 3 for reflux. The uncondensed DME, C3, and other light components are condensed into liquid phase again by the light component condenser 6 and then enter the light component buffer tank 7 and are sent to the tank area. The post-ether C4 collected from the bottom of the DME tower after DME removal is cooled by the feed heat exchanger 2 and the discharge cooler 8 and then returned to the isobutane dehydrogenation unit as raw material for reuse.

[0030] Furthermore, a booster pump 9 is installed on the pipeline between the post-ether C4 buffer tank 1 and the dimethyl ether removal tower 3.

[0031] In the above technical solution, by installing a booster pump 9 on the pipeline between the post-ether C4 buffer tank 1 and the dimethyl ether removal tower 3, a stable and sufficient pressure feed can be provided to the dimethyl ether removal tower 3, ensuring the efficient operation of the distillation process.

[0032] Furthermore, a light component extraction pump 10 is installed on the pipeline between the light component buffer tank 7 and the tank area.

[0033] In the above technical solution, by installing a light component extraction pump 10 on the pipeline between the light component buffer tank 7 and the tank area, the light component liquid in the buffer tank can be stably transported to the tank area for storage.

[0034] Furthermore, a reflux pump 11 is installed on the pipeline between the bottom outlet of the reflux tank 5 and the top inlet of the dimethyl ether removal tower 3.

[0035] In the above technical solution, by installing a reflux pump 11 on the pipeline between the bottom outlet of the reflux tank 5 and the top inlet of the dimethyl ether removal tower 3, the stable operation and efficient separation of the dimethyl ether removal tower 3 can be guaranteed.

[0036] This utility model's high-value utilization device for isobutane, through structural optimization design, dehydrogenates isobutane and sends it to the MTBE unit to produce MTBE. Then, it removes dimethyl ether from the C4 after etherification through the dimethyl ether removal unit and returns it as a raw material for isobutane dehydrogenation. This almost completely digests the isobutane in the raw material, realizes high-value utilization of isobutane, reduces production costs, and improves economic benefits.

[0037] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0038] Furthermore, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0039] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0040] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for high-value utilization of isobutane, characterized in that, The apparatus includes an isobutane dehydrogenation unit, an MTBE unit, and a dimethyl ether removal unit; one outlet of the isobutane dehydrogenation unit is connected to the inlet of the MTBE unit, the outlet of the MTBE unit is connected to the inlet of the dimethyl ether removal unit, and the outlet of the dimethyl ether removal unit is connected to the inlet of the isobutane dehydrogenation unit.

2. The apparatus for high-value utilization of isobutane according to claim 1, characterized in that, The apparatus also includes a PSA unit, with another outlet of the isobutane dehydrogenation unit connected to the inlet of the PSA unit.

3. The apparatus for high-value utilization of isobutane according to claim 1 or 2, characterized in that, The dimethyl ether removal unit includes a post-ether C4 buffer tank, a feed heat exchanger, a dimethyl ether removal tower, an air cooler, a reflux tank, a light component condenser, a light component buffer tank, and a discharge cooler. The inlet of the post-ether C4 buffer tank is connected to the outlet of the MTBE unit. The outlet of the post-ether C4 buffer tank is connected to the upper feed inlet of the dimethyl ether removal tower via a pipeline through the feed heat exchanger. The top discharge outlet of the dimethyl ether removal tower is connected to the inlet of the reflux tank via a pipeline through the air cooler. The top outlet of the reflux tank is connected to the inlet of the light component buffer tank via a pipeline through the light component condenser. The outlet of the light component buffer tank is connected to the tank area via a pipeline. The bottom outlet of the reflux tank is connected to the top feed inlet of the dimethyl ether removal tower via a pipeline. The bottom discharge outlet of the dimethyl ether removal tower is connected to the inlet of the isobutane dehydrogenation unit via a pipeline, sequentially through the feed heat exchanger and the discharge cooler.

4. The apparatus for high-value utilization of isobutane according to claim 3, characterized in that, A booster pump is installed on the pipeline between the post-ether C4 buffer tank and the dimethyl ether removal tower.

5. The apparatus for high-value utilization of isobutane according to claim 3, characterized in that, A light component extraction pump is installed on the pipeline between the light component buffer tank and the tank area.

6. The apparatus for high-value utilization of isobutane according to claim 3, characterized in that, A reflux pump is installed on the pipeline between the bottom outlet of the reflux tank and the top inlet of the dimethyl ether removal tower.

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