CN201524434U - An integrated evaporator for carbonylation synthesis of acetic acid - Google Patents

Abstract

The utility model relates to an integrated evaporator for carbonylation acetic acid technology, comprising a washing section (9), a separation collection section (8) and a heating section (7) which are connected with each other in turn from up to down, wherein the separation collection section (8) is connected with the heating section (7) by a transition section and the washing section (9) is connected with the separation collection section (8) by a flange and the top of the washing section (9) is provided with a flash vapor phase outlet (3) and the side surface is provided with a washing liquid inlet (2) and a float valve tray (15) is arranged inside. Because the washing section (9) is added, the hydrogen iodide and rhodium catalyst are thoroughly separated from the flash vapor phase and returned into a reaction kettle (c) together with the mother liquid to greatly reduce the running-off of the catalyst, reduce the separation load of the subsequent separation system and also reduce the operation cost and corrosion of the separation system and be more favorable for stable operation of the carbonylation acetic acid technology and furthermore increase the quality and yield of acetic acid.

Description

A kind of integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation

Technical field

The utility model relates to a kind of evaporimeter, relates in particular to a kind of integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation.

Technical background

Acetic acid is important chemical intermediate and chemical reaction solvent, and U.S. Monsanto Company has developed the production technology of acetic acid synthesis from methanol carbonylation, and this technology has become the main method of producing acetic acid in the world at present.

The production technology of acetic acid synthesis from methanol carbonylation, mainly be that methyl alcohol, carbon monoxide and catalyst etc. add reactor bottom, react under uniform temperature and pressure, reactant liquor is drawn in the top of reactor side line in the reaction back, and decompression makes product separate with the mother liquor that contains catalyst.The reaction mixture that contains thick acetic acid, light fraction enters the lightness-removing column of refining system with gas phase, deviates from light fraction, and the gas of cat head enters scrubbing tower through destilling tower condensation liquid bath.The still liquid of lightness-removing column is moisture thick acetic acid, is sent to dehydrating tower, and the dry crude acetic acid of dehydrating tower bottom is admitted to weight-removing column again.Draw finished acid from weight-removing column top side line; Acetic acid in the weight-removing column bottom fraction is sent to waste acid column at last, to recycle.

In the above-mentioned technological process of production, reactant liquor enters evaporimeter, and product is separated therein with the mother liquor of rhodium-containing catalyst.Owing to carrying rhodium catalyst secretly in the flash gas (mainly being acetic acid) at existing evaporimeter top and hydrogen iodide gas enters follow-up rectifying piece-rate system, causing the catalyst of synthesis procedure constantly to run off.In addition, content of iodine is higher in the flash gas at evaporimeter top, and the segregational load of subsequent separation system is increased, and energy consumption increases, and the corrosion of later separation equipment aggravation, both has been unfavorable for the stable operation of device, and the aging speed of device is accelerated.

The utility model content

The purpose of this utility model is that carbonylation synthesizes the separation of hydrogen iodide in the acetic acid and the technical problem that rhodium catalyst reclaims in order to solve in the prior art, and a kind of novel integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation is provided.

The utility model at first provides a kind of integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation, this integrated form evaporimeter, comprise separated and collectedsection 8 and bringing-upsection 7, connect with changeover portion between separated and collectedsection 8 and the bringing-upsection 7, described separated and collectedsection 8 sides are provided withflash steam import 1, bringing-upsection 7 bottoms are provided with motherliquor return port 4, the side is provided withheating steam inlet 5 andcondensate outlet 6, also comprisewashing section 9, be connected with flange betweenwashing section 9 and the separated and collectedsection 8, describedwashing section 9 tops are provided with flash distillationgaseous phase outlet 3, and the side is provided withcleaning solution inlet 2, and inside is provided withfloat valve tray 15.

The utility model also provides the above-mentioned optimal technical scheme that is used for the integrated form evaporimeter of the synthetic acetic acid technology of carbonylation:

The quantity of describedfloat valve tray 15 is 5～10 layers.

The inside of described bringing-upsection 7 is provided with the heat(ing)coil 14 of outer wall polishing.

The top of described separated and collectedsection 8 is provided withwire mesh demister 12, and the top ofwire mesh demister 12 iscone 10, andcone 10 inside are provided withcyclonic separation plate 11; The bottom ofwire mesh demister 12 is provided withsilk screen 13.

The porosity of describedsilk screen 13 is 0.9～0.97, highly is 150～250mm.

Describedsilk screen 13 is a woven wire.

The axis angle of described cyclonic separation plate andcone 10 is 30 °～60 °, and the cyclonic separation plate is 8～16.

The highly effective integration evaporator application that the utility model provides is in the flash distillation operation of the synthetic acetic acid technology of carbonylation, and reached following effect: (1) has improved the purity of flash gas, has separated hydrogen iodide effectively; (2) reduce the load of lightness-removing column, reduced the operating cost of device; (3) reclaim rhodium catalyst more up hill and dale, reduced the consumption of rhodium catalyst; (4) reduced corrosion, more helped the stable operation of acetic acid plant in the synthetic acetic acid technology of carbonylation later separation equipment; (5) quality and the output of acetate products have been improved.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Among Fig. 1,1 is the flash steam import; 2 are the cleaning solution inlet; 3 are the flash distillation gaseous phase outlet; 4 is the mother liquor return port; 5 are the heating steam inlet; 6 is condensate outlet; 7 is bringing-up section; 8 is the separated and collected section; 9 is washing section; 10 is cone; 11 is cyclone separator; 12 is wire mesh demister; 13 is silk screen; 14 is heat(ing) coil; 15 is float valve tray.

Fig. 2 is the application of the utility model in the synthetic acetic acid technological process of carbonylation.

Among Fig. 2, a is a carbon monoxide; B is a methyl alcohol; C is a reactor; D is a cleaning solution; The integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation that e provides for the utility model; F is a flash steam; G is a mother liquor; H is the flash distillation gas phase; I is a distillation system; 1 is the flash steam import; 2 are the cleaning solution inlet; 3 are the flash distillation gaseous phase outlet; 4 is the mother liquor return port; 7 is bringing-up section; 8 is the separated and collected section; 9 is washing section.

The specific embodiment

According to manufacturing technique requirent, evaporimeter on the existing running gear is carried out technological improvement, set up wash mill at the equipment top, simultaneously the internal structure of original evaporimeter has been carried out optimizing (heat(ing) coil that original common heating coil pipe in the bringing-upsection 7 is changed into the outer wall polishing).The highly effective integration washing evaporimeter that uses the utility model to provide, improved the purity of flash gas, hydrogen iodide gas has obtained effective washing to be separated, with the mother liquor Returning reacting system, reduce the separating energy consumption of subsequent separation system, effectively reduced the etching problem of later separation equipment.Rhodium catalyst reclaims more thorough, can reduce the consumption of rhodium catalyst in stable the recycling of reaction zone.

Below in conjunction with Fig. 1,2 the utility model is described in further detail so that those skilled in the art can better understand and can be implemented, but illustration is not as to qualification of the present utility model.

Among Fig. 1, the utility model compriseswashing section 9, separated and collectedsection 8 and the bringing-upsection 7 that from top to bottom connects successively, wherein, connect with changeover portion between separated and collectedsection 8 and the bringing-upsection 7, be connected with flange betweenwashing section 9 and the separated and collectedsection 8, this flange connects the current check and the parking maintenance of the equipment of being convenient to.Flash steam (main component is the acetate that methanol carbonyl is combined to) enters separated and collectedsection 8 throughflash steam import 1, vapour phase enterswashing section 9, cleaning solution enters 9 pairs of vapour phases that enter of washing section fromcleaning solution inlet 2 and washs, the flash distillation gas phase is dischargedwashing section 9 from flash distillationgaseous phase outlet 3, and liquid phase is returned separated and collected section 8.Washing section 9 is provided with 7 layersfloat valve tray 15, and this evaporimeter is owing to increasedwashing section 9, and reached following effect: (1) has improved the flash distillation effect effectively, makes that the content of iodine in the flash gas component is very low; (2) reclaim rhodium catalyst more completely, also reduced the consumption of catalyst; (3) alleviate the segregational load of subsequent separation system (mainly referring to lightness-removing column), and then reduced the operating cost of this piece-rate system; (4) avoid the corrosion of later separation equipment, more helped the stable operation of later separation equipment, thereby also more helped the synthetic acetic acid technology of carbonylation; (5) quality and the output of acetate products have been improved.The liquid phase of separated and collectedsection 8 turns back to the reactor from motherliquor return port 4 after bringing-up section 7.The bottom of separated and collectedsection 8 is provided withwire mesh demister 12, and the top of thiswire mesh demister 12 iscone 10, andcone 10 inside are provided withcyclone separator 11, can be the cyclonic separation plate, and cyclonic separation plate and cone axis are at 45, and quantity is 8; The bottom ofwire mesh demister 12 is provided withsilk screen 13, and the porosity of thissilk screen 13 is 0.93, highly is 200mm.Heating steam is heated from 14 pairs of bringing-upsections 7 of heat(ing) coil thatheating steam inlet 5 enters the outer wall polishing of bringing-upsection 7, and condensed condensate liquid is discharged bringing-upsection 7 from condensate outlet 6.The heat(ing)coil 14 of outer wall polishing has reduced the absorption to valuable rhodium catalyst effectively, has increased the rate of recovery of rhodium catalyst.

The technological process of acetic acid synthesis from methanol carbonylation is as shown in Figure 2: carbonylation takes place down in uniform temperature and pressure and generates acetic acid in reactor c in material benzenemethanol b and carbon monoxide a.After flash steam f (mainly being the acetic acid that generates) discharges from reactor c, enter the separated and collectedsection 8 of the integrated form evaporimeter e that is used for the synthetic acetic acid technology of carbonylation that the utility model provides throughflash steam import 1, gas phase in the separated and collectedsection 8 enterswashing section 9, cleaning solution d enters 9 pairs of gas phases that enterwashing section 9 of washing section fromcleaning solution inlet 2 and washs, and flash distillation gas phase h discharges from flash distillationgaseous phase outlet 3 and enters distillation system i behind thewashing section 9 of integrated form evaporimeter e and carry out further rectifying.Liquid phase in thewashing section 9 is returned separated and collectedsection 8, and mother liquor g turns back to the reactor c from motherliquor return port 4 after bringing-up section 7.Because the integrated form evaporimeter that provides of the utility model has increased washing section, can wash effectively, thereby improve the purity of flash gas, separated hydrogen iodide effectively, reduced the load of lightness-removing column, reduced the operating cost of device; Reclaim rhodium catalyst more up hill and dale, reduced the consumption of catalyst; Reduced corrosion simultaneously, more helped the stable operation of acetic acid plant in the synthetic acetic acid technology of carbonylation later separation equipment; Also improved the quality of acetate products.

The above embodiment is the preferred embodiment that proves absolutely that the utility model is lifted, and protection domain of the present utility model is not limited thereto.Being equal to that those skilled in the art are done on the utility model basis substitutes or conversion, all within protection domain of the present utility model.

Claims (7)

1. one kind is used for the integrated form evaporimeter that carbonylation synthesizes acetic acid technology, comprise separated and collected section (8) and bringing-up section (7), connect with changeover portion between separated and collected section (8) and the bringing-up section (7), described separated and collected section (8) side is provided with flash steam import (1), bringing-up section (7) bottom is provided with mother liquor return port (4), the side is provided with heating steam inlet (5) and condensate outlet (6), it is characterized in that: also comprise washing section (9), be connected with flange between washing section (9) and the separated and collected section (8), described washing section (9) top is provided with flash distillation gaseous phase outlet (3), the side is provided with cleaning solution inlet (2), and inside is provided with float valve tray (15).

2. be used for the integrated form evaporimeter of the synthetic acetic acid technology of carbonylation according to claim 1, it is characterized in that: the quantity of described float valve tray (15) is 5～10 layers.

3. be used for the integrated form evaporimeter of the synthetic acetic acid technology of carbonylation according to claim 1, it is characterized in that: the inside of described bringing-up section (7) is provided with the heat(ing) coil (14) of outer wall polishing.

4. the integrated form evaporimeter that is used for the synthetic acetic acid technology of carbonylation as claim 1～3 as described in each, it is characterized in that: the top of described separated and collected section (8) is provided with wire mesh demister (12), the top of wire mesh demister (12) is cone (10), and cone (10) inside is provided with cyclonic separation plate (11); The bottom of wire mesh demister (12) is provided with silk screen (13).。

5. be used for the integrated form evaporimeter that carbonylation synthesizes acetic acid technology as described in claim 4, it is characterized in that: the porosity of described silk screen (13) is 0.9～0.97, highly is 150～250mm.

6. be used for the integrated form evaporimeter that carbonylation synthesizes acetic acid technology as described in claim 4, it is characterized in that: described silk screen (13) is a woven wire.

7. be used for the integrated form evaporimeter that carbonylation synthesizes acetic acid technology as described in claim 4, it is characterized in that: the axis angle of described cyclonic separation plate and cone (10) is 30 °～60 °, and the cyclonic separation plate is 8～16.

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