CN210855907U - Solvent recovery device - Google Patents

Abstract

The utility model discloses a solvent recovery unit, including sediment fluid reservoir, screw pump, centrifuge, recovery unit, sediment liquid inlet pipe, sediment liquid discharging pipe, screw pump outlet pipe, the sediment liquid inlet pipe through first valve with the upper portion of sediment fluid reservoir is connected, the sediment liquid discharging pipe is located the well lower part of sediment fluid reservoir, the sediment liquid discharging pipe through the second valve with the screw pump is connected, the screw pump outlet pipe through the fifth valve with centrifuge's entry linkage, centrifuge's light phase export through eighth valve, solvent extraction pipe with recovery unit's entry linkage. The utility model has the advantages of reasonable design: the slag and liquid are separated by a centrifugal machine, so that the solvent is recovered; the heavy phase outlet material of the centrifuge is returned to the lower half part of the slag liquid tank for cyclic separation and recovery, so that the recovery rate of the solvent is improved; the operation mode of continuously receiving the slag liquid and intermittently separating and recovering the solvent reduces the energy consumption of solvent recovery.

Description

Solvent recovery device

Technical Field

The utility model relates to a chemical industry technical field especially relates to a solvent recovery unit.

Background

At present, in the process for producing maleic anhydride by n-butane oxidation, a DBP (dibutyl phthalate) solvent is generally adopted to recover a maleic anhydride product. During the production process, DBP solvent is easily decomposed to form phthalic anhydride, and maleic anhydride is easily hydrolyzed to form fumaric acid. In addition, a small amount of tar is generated while the maleic anhydride product is generated by the reaction. The accumulation of these three types of impurities is likely to cause system plugging. To prevent impurities from accumulating and clogging equipment and piping, it is a common and cost-effective practice to extract phthalic anhydride and fumaric acid in the solvent DBP with hot water and then separate them with a centrifuge. The separated oil phase is the purified solvent DBP, most phthalic anhydride and fumaric acid enter a sewage treatment system along with the water phase, and tar is discharged out of the system in the form of slag liquid. The slag liquid not only contains tar, but also contains a large amount of DBP. At present, maleic anhydride production enterprises mainly adopt a treatment mode of directly sending slag liquid to an incinerator for incineration, and do not carry out further solvent recovery treatment, so that the DBP solvent is wasted, and therefore, designing a device capable of recovering the DBP solvent in the slag liquid is an urgent problem, but the device is a great challenge for related designers.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a solvent recovery unit to solve the DBP solvent in the current sediment liquid and not retrieve and cause the problem of wasting of resources.

In order to realize the above purpose, the technical scheme of the utility model a solvent recovery device is provided, including sediment fluid reservoir, screw pump, centrifuge, recovery unit, sediment liquid inlet pipe, sediment liquid discharging pipe, screw pump outlet pipe, the sediment liquid inlet pipe through first valve with the upper portion of sediment fluid reservoir is connected, the sediment liquid discharging pipe is located the well lower part of sediment fluid reservoir, the sediment liquid discharging pipe through the second valve with the screw pump is connected, the screw pump outlet pipe through the fifth valve with centrifuge's entry linkage, centrifuge's light phase export through eighth valve, solvent extraction pipe with recovery unit's entry linkage.

Further, a light phase outlet of the centrifuge is connected with the slag liquid tank through a seventh valve and a light phase circulating pipe.

Further, a heavy phase outlet of the centrifuge is connected with the lower part of the slag liquid tank through a third valve and a heavy phase circulating pipe.

Further, a slag discharging pipe is arranged at the bottom of the slag liquid tank.

Further, the slag discharge pipe is connected to the screw pump through a fourth valve.

Further, the screw pump is connected to the incineration device through a sixth valve.

Further, the incineration device is an incinerator.

In any one of the above technical solutions, the recovery device is a recovery tank.

To sum up, the application the technical scheme of the utility model, following beneficial effect has: the utility model has reasonable structural design, and can separate the slag liquid through the centrifuge and convey the separated DBP solvent to the recovery tank, thereby effectively completing the recovery of the DBP solvent; the material at the heavy phase outlet of the centrifuge is returned to the lower half part of the slag liquid tank for cyclic separation and recovery, so that the tar impurities are continuously concentrated, and when the tar impurities in the slag liquid tank reach a certain concentration, the tar impurities are conveyed to the incinerator for combustion, and the recovery rate of the DBP solvent is effectively improved; by adopting the operation mode of continuously receiving the slag liquid and intermittently separating and recovering the solvent, the energy consumption of DBP solvent recovery is effectively reduced.

Drawings

FIG. 1 is a schematic structural view of a solvent recovery apparatus according to the present invention;

description of reference numerals: 1. the device comprises a slag liquid tank, 11, a slag liquid feeding pipe, 12, a slag liquid discharging pipe, 13, a slag discharging pipe, 14, a first valve, 15, a second valve, 16, a fourth valve, 2, a screw pump, 21, a screw pump outlet pipe, 22, a fifth valve, 23, a sixth valve, 3, a centrifuge, 31, a light phase outlet, 32, a light phase circulating pipe, 33, a solvent extraction pipe, 34, a heavy phase circulating pipe, 35, an eighth valve, 36, a seventh valve, 37, a third valve, 4, a recycling device, 5 and an incineration device.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, but the technical solution does not limit the scope of the present invention.

In the present invention, for the sake of clearer description, the following explanation is made: an observer viewing the attached figure 1 should point out that the terms "upper", "lower middle", "bottom" and the like herein indicate orientations or positional relationships based on the orientation or positional relationships set forth in the drawings, and are only for the purpose of clearly describing the present invention, and do not indicate or imply that the structures or components referred to must have a particular orientation, be configured in a particular orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," "seventh," and "eighth" are used merely for purposes of clarity or simplicity of description, and are not to be construed as indicating or implying a relative importance or quantity.

Referring to fig. 1, the present embodiment provides a solvent recovery device, which includes a residue liquid tank 1, a screw pump 2, a centrifuge 3, a recovery tank, and a plurality of pipelines and valves. A slag liquid feeding pipe 11 is connected with the upper part of the slag liquid tank 1 through a first valve 14, a slag liquid discharging pipe 12 is positioned at the middle lower part of the slag liquid tank 1 and is connected with a screw pump 2 through a second valve 15, and an outlet pipe 21 of the screw pump is connected with an inlet of a centrifuge 3 through a fifth valve 22; the light phase outlet 31 of the centrifuge 3 is connected with the slag liquid tank 1 through a seventh valve 36 and a light phase circulating pipe 32 on one hand, and is connected with the inlet of the recovery tank through an eighth valve 35 and a solvent extraction pipe 33 on the other hand; the heavy phase outlet of the centrifuge 3 is connected with the lower part of the slag liquid pot 1 through a third valve 37 and a heavy phase circulating pipe 34, and a slag discharging pipe 13 positioned at the bottom of the slag liquid pot 1 is connected with the incinerator through a fourth valve 16, a screw pump 2 and a sixth valve 23. Of course, the recovery device 4 may be replaced with another type having the same function as the recovery tank, and the same function may be achieved, and the incineration device 5 may be replaced with another type having the same function as the incineration furnace, and the same function may be achieved.

Specifically, the utility model discloses can be used to the solvent recovery process in the maleic anhydride technology, through receiving the sediment liquid, separate recovery solvent, concentration and arrange the three process of sediment, under lower energy consumption, the solvent in the sediment liquid is retrieved in the separation, is continuous operation when receiving the sediment liquid, and the separation is retrieved solvent, is concentrated and arranges the sediment process and is intermittent type operation.

In actual work, the method comprises the following three steps: receiving slag liquid, keeping the first valve 14 normally open, closing the second valve 15 to the eighth valve 35, and keeping the screw pump 2 and the centrifuge 3 in a shutdown state, wherein at the moment, the slag liquid with small flow continuously flows into the slag liquid tank 1, and when the slag liquid tank 1 reaches a certain liquid level which is 60-80%; separating and recovering the solvent, opening a second valve 15 and a fifth valve 22, starting a screw pump 2, starting a centrifuge 3, opening a third valve 37 and a seventh valve 36, continuously separating the light phase and the heavy phase circulating and returning to the residue liquid tank 1, slowly opening an eighth valve 35 and closing the seventh valve 36 when the centrifuge 3 runs stably and no tar impurities appear in a sight glass of a light phase outlet 31, recovering the DBP solvent into a recovery tank, stopping recovering the DBP solvent when the sight glass shows that the tar impurities appear, and stopping the operation of the centrifuge 3 and the screw pump 2; concentrating and deslagging, closing a second valve 15 to an eighth valve 35, opening a first valve 14, repeatedly receiving slag liquid, separating and recovering a solvent, concentrating the slag liquid until the slag liquid reaches an expected concentration (the tar content is 90-95 wt%), opening a fourth valve 16 and a sixth valve 23 when the slag liquid is concentrated to the expected concentration, starting a screw pump 2, transferring the high-concentration slag liquid to an incinerator for incineration treatment, stopping the operation of the screw pump 2 when the liquid level of a slag liquid tank 1 is lowered to a certain degree and is 10% -20%, closing the fourth valve 16 and the sixth valve 23, completing an operation cycle at this moment, and returning to the step of receiving the slag liquid.

The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations are also considered as the protection scope of the present invention.

Claims (8)

1. A solvent recovery device: including sediment fluid reservoir (1), screw pump (2), centrifuge (3), recovery unit (4), sediment liquid inlet pipe (11), sediment liquid discharging pipe (12), screw pump outlet pipe (21), its characterized in that: the slag liquid feeding pipe (11) is connected with the upper portion of the slag liquid tank (1) through a first valve (14), the slag liquid discharging pipe (12) is located at the middle lower portion of the slag liquid tank (1), the slag liquid discharging pipe (12) is connected with the screw pump (2) through a second valve (15), an outlet pipe (21) of the screw pump is connected with an inlet of the centrifuge (3) through a fifth valve (22), and a light phase outlet (31) of the centrifuge (3) is connected with an inlet of the recovery device (4) through an eighth valve (35) and a solvent extraction pipe (33).

2. The solvent recovery apparatus of claim 1, wherein: and a light phase outlet (31) of the centrifuge (3) is connected with the slag liquid tank (1) through a seventh valve (36) and a light phase circulating pipe (32).

3. The solvent recovery apparatus of claim 2, wherein: the heavy phase outlet of the centrifuge (3) is connected with the lower part of the slag liquid tank (1) through a third valve (37) and a heavy phase circulating pipe (34).

4. A solvent recovery apparatus as defined in claim 3, wherein: and a slag discharge pipe (13) is arranged at the bottom of the slag liquid tank (1).

5. The solvent recovery apparatus of claim 4, wherein: the slag discharge pipe (13) is connected to the screw pump (2) through a fourth valve (16).

6. The solvent recovery apparatus of claim 5, wherein: the screw pump (2) is connected to the incineration device (5) through a sixth valve (23).

7. The solvent recovery apparatus of claim 6, wherein: the incinerator (5) is an incinerator.

8. The solvent recovery apparatus according to any one of claims 1 to 7, wherein: the recovery device (4) is a recovery tank.

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