CN208471943U - A kind of aromatic carboxylic acid's process units of energy-saving and environmental protection - Google Patents

Abstract

The utility model relates to a kind of energy conservations, aromatic carboxylic acid's process units of environmental protection, including oxidation section and refinement, oxidation section includes first-stage reactor and second reactor, first-stage reactor connects tail gas washing tower and heat recovery boiler, level-one mixing, washing tower is sequentially connected waste heat boiler connection and primary heater, waste heat boiler is connected with first-stage reactor feed preheater with primary heater, first-stage reactor feed preheater is connected with first-stage reactor and azeotropic distillation device respectively, level-one mixing, washing tower is connected by mixture pump with first-stage reactor, primary heater is separately connected secondary scrubber, extraction tower, azeotropic distillation device and secondary heater, second reactor is connected with oxidizing and crystallizing unit, oxidizing and crystallizing unit is connected with oxidation filter element, oxidation filter element is connected with refinement.The utility model can comprehensively recycle tail gas, refinement mother liquor and solid waste, and energy consumption, the material consumption of entire technique can be substantially reduced.

Description

A kind of aromatic carboxylic acid's process units of energy-saving and environmental protection

Technical field

The utility model relates to PTA production fields, more particularly to a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection.

Background technique

Terephthalic acid (TPA) is the important source material for producing polyester (PET) fiber and resin, mainly empty using paraxylene at present Raw material paraxylene is dissolved in containing catalyst acetic acid brill, manganese acetate, hydrogen bromide (or tetrabromo by the production of gas oxidizing process, this method Ethane) acetic acid solvent in, be passed through air or oxygen rich air aoxidized, generate solid product terephthalic acid (TPA).Typical reaction Temperature is 155-205 DEG C, pressure 0.5-1.6MPa, residence time 40-120min, and reaction heat is evaporated by solvent to be removed, steam After condensation in Returning reactor, the slurry of generation obtains p-phthalic acid (PTA) with refining step using subsequent separation Product.

The production procedure of TA includes three reaction member, tail gas treating unit and slurry processing unit major parts.Raw material Oxidation reactor is added in paraxylene and air, and liquid phase oxidation occurs under the effect of the catalyst, generates solid terephthalic acid. Slurry enters slurry processing unit after reactor bottom discharge, and the main task of the unit is separation mother liquor and TA solid, returns The energy in slurry is received, purified treatment is carried out to control impurity concentration to mother liquor, while recycling catalyst.Reaction heat passes through solvent The evaporation of acetic acid is taken out of, and acetic acid steam removes reactor from top together with tail gas, into tail gas treating unit.The master of the unit Wanting task is recycling reaction heat, recovery of acetic acid solvent, cleaning of off-gas.

(1.26x 10 is released after every kilogram of p xylene oxidation since p xylene oxidation process thermal discharge is very big⁷J's is anti- Answer heat), while process each unit and plant capacity consumption are also very high, therefore the comprehensive utilization of energy is exactly one and critically important asks Topic, needs to carry out mature consideration in terms of reactor design and process design, and it is existing for how reducing energy consumption, eliminating the generation of solid waste Mainly wanting improved aspect.

Summary of the invention

The technical problem to be solved by the utility model is to provide a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection, can Comprehensively to be recycled to tail gas, refinement mother liquor and solid waste, energy consumption, the material consumption of entire technique can be substantially reduced, with biography The process flow of system, which is compared, biggish change.

The technical scheme adopted by the utility model to solve the technical problem is as follows: providing a kind of aromatics carboxylic of energy-saving and environmental protection Sour device, including oxidation section and refinement, the oxidation section include the first order reaction to connect with external compression air Device and second reactor, the first-stage reactor connect tail gas washing tower, and tail gas washing tower connects heat recovery boiler, the tail Gas wash tower is to wash the organic matters such as the PT carried secretly in tail gas acid, paraxylene, methyl acetate, the heat recovery boiler and one Grade mixing, washing tower is connected, and the level-one mixing, washing tower is connect with waste heat boiler, and waste heat boiler is connected with primary heater, Waste heat boiler is connected with first-stage reactor feed preheater with primary heater, the first-stage reactor feed preheater point It is not connected with first-stage reactor and azeotropic distillation device, the level-one mixing, washing tower passes through mixture pump and first order reaction Device is connected, and the primary heater is separately connected secondary scrubber, extraction tower, azeotropic distillation device and secondary heater, institute The second reactor stated is connected with oxidizing and crystallizing unit, and the oxidizing and crystallizing unit is connected with oxidation filter element, described Oxidation filter element is connected with refinement.

As a kind of supplement to technical solution described in the utility model, the oxidation section further includes mixed with level-one Close the connected cyclone separator of scrubbing tower and first-stage reactor, the external product containing fine particle of the cyclone separator and in Between product hot waste water.

Further, the secondary scrubber is connected with reaction end gas recyclable device, and the reaction end gas recycles dress It sets and is connected with tail gas burning unit.

Further, the refinement includes the purification material-compound tank being connected with oxidation filter element, the purification Material-compound tank is connected by several preheaters with hydrogenator, and refining crystallization list is sequentially connected after the hydrogenator Member, refining filtering unit and purification drying unit.

Further, the refining crystallization unit is connected with emptying purifying column.

Further, the preheater is connected with waste heat recovery plant and secondary heater respectively.

Further, the refining filtering unit is connected with the cleaning solution heater for heated scrub.

Further, the oxidation filter element is connected with filtrate cooling vacuum filtration system, the filtrate cooling vacuum Filtration system is connected with oxidation residua processing unit.

As a kind of aromatic carboxylic acid production process method of energy-saving and environmental protection, the specific method is as follows:

(a) oxidation operation:

Air compressor provides compressed air to first-stage reactor and second reactor, aoxidizes the liquid of material-compound tank by one Fed after the heating of stage reactor feed preheater to first-stage reactor, made by the way that a certain proportion of cobalt, manganese, bromine catalyst is added be The catalyst of system reaches suitable concentration, so as to adjust reaction degree and control reaction depth；In oxidation reaction unit, level-one The method that reactor and second reactor use different operation pressure, to reduce the consumption of raw material in reaction process, acetic acid；

The solvent vapo(u)r generated in first-stage reactor is mixed with reaction end gas, is entered tail gas by blow-down pipe and is washed The organic matters such as paraxylene, the methyl acetate carried secretly in tower washing tail gas are washed, solvent vapo(u)r and reaction end gas after washing enter Heat recovery boiler output low-pressure steam, the hot waste water from refined unit is after cyclone separator is handled and passes through waste heat Uncooled solvent vapo(u)r and reaction end gas enter level-one mixing, washing tower after recycling boiler energy recycling, laggard through mixing, washing Enter the different grades of steam of waste heat boiler output at different levels, level-one mixing, washing tower tower bottom mixed liquor is delivered to one by mixture pump In stage reactor；

By after waste heat boiler and uncooled solvent vapo(u)r and reaction end gas enter primary heater and heat waste heat boiler The liquid being condensed in moisturizing, waste heat boiler and primary heater heats mixed feeding through first-stage reactor feed preheater It is sent into first-stage reactor, extraction tower and azeotropic distillation device afterwards, meanwhile, reaction end gas enters secondary scrubber, washs in second level In tower, reaction end gas is sent after peracetic acid, desalination water washing to reaction end gas energy recycle device, the reaction tail after energy regenerating Gas enters tail gas burning unit and is ultimately discharged into atmosphere；

Oxidation slurry after first-stage reactor and second reactor control impurity concentration enters oxidizing and crystallizing unit, in oxygen Change oxidation slurry in crystalline element and enter oxidation filter element after step pressure reducing, cooling, from big portion after oxidizing and crystallizing unit The terephthalic acid crystals of point dissolution are precipitated, and the crude terephthalic acid product of precipitation after filtering and washing by sending to purification ingredient Tank, filtrate and cleaning solution are delivered in oxidation material-compound tank by delivery pump.

(b) refining step:

Uniform slurry is mixed into purification material-compound tank by being added after water from the thick TA product of oxidation filter element The TA slurry of moderate concentration, the TA slurry dissolved in purification material-compound tank after booster pump pressurization and the heating of preheated device by being sent into Hydrogenator, the lime set that the heating period generates heat waste heat boiler moisturizing by secondary heater, and hot fixed gas first passes through Waste heat recovery plant generates high-grade steam, then by Washing of Filter Cake needed for cleaning solution heater heating refining filtering unit Liquid eventually enters into the hydrogen in waste heat recovery unit recycling exhaust gas；

By the way that suitable hydrogen is added in hydrogenator, reduction reaction occurs after being sufficiently mixed it with slurry, instead PTA slurry after answering enters refining crystallization unit, after the flash-off steam generated in refining crystallization unit preheated device heat exchange its Fixed gas enters emptying purifying column, and entrainer heater is equipped in emptying purifying column for heating used in azeotropic distillation device Entrainer；Tail gas, which is sent into, through blower by the washing of emptying purifying column, purified gas burns unit.

In refining crystallization unit, by step pressure reducing, cooling so that PTA is precipitated from solvent and is sent into refining filtering list Member, by being sent after filtering and washing to purification drying unit, the washed tower heat exchanger of steam evaporated in purification drying unit PTA device auxiliary unit water is heated, energy consumption is reduced, the PTA product after purification drying unit is dry is ultimately delivered to storage material Storehouse.

In order to which except the impurity in deoxidation filter element filtrate, extraction section filtrate is sent to filtrate cooling vacuum from filtrate Filtration system is sent through cooling, filtered residue to oxidation residua unit, and oxidation residua is using complete molten method operation, recycling oxidation Cobalt, manganese Metal in residue reduce solid waste discharge, and waste water is discharged into sewage unit, and biogas is generated in anaerobism and is used as fuel.

The utility model has the advantages that the utility model relates to a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection, it can be to tail gas, essence Mother liquor processed and solid waste are comprehensively recycled, and energy consumption, the material consumption of entire technique can be substantially reduced, with traditional process flow Compared to there is biggish change, have the advantage that

1. extracting water extra in system with the method that azeotropic rectifier unit combines using extraction tower, the method can be with Reduce azeotropic distillation device operating load and steam consumption, reduce production cost, while greatly improve system stability and Operating flexibility；

2. extraction section filtrate is sent cooling true to filtrate from filtrate in order to except the impurity in deoxidation filter element filtrate Empty filtration system is sent through cooling, filtered residue to oxidation residua unit, and oxidation residua recycles oxygen using complete molten method operation Cobalt, manganese Metal in change residue, reduce solid waste discharge, and waste water is discharged into sewage unit, and biogas is generated in anaerobism and is used as fuel, Energy conservation and environmental protection；

3. increasing tail gas washing tower at the top of oxidation reactor, the solvent vapo(u)r generated in reactor is mixed with reaction end gas Together, tail gas washing tower is entered by blow-down pipe to wash PT acid, paraxylene, methyl acetate for carrying secretly etc. in tail gas organic Object can reduce the risk of heat recovery boiler tubulation blocking and further decrease the consumption of paraxylene；

4. the washed tower heat exchanger heating PTA device auxiliary unit water of the steam evaporated in purification drying unit, drop Low energy consumption.

5. refining the lime set that the preheater heating period generates heats waste heat boiler moisturizing by secondary heater, hot does not coagulate Gas first passes through waste heat recovery plant and generates high-grade steam, then using filter needed for cleaning solution heater heating and filtering unit Cake cleaning solution, it is more rationally effective to reduce energy loss, reduce energy consumption.

Detailed description of the invention

Fig. 1 is the flow chart of the utility model.

Diagram: 01, first-stage reactor；02, tail gas washing tower；03, heat recovery boiler；04, level-one mixing, washing tower； 05, cyclone separator；06, mixture pump；07, waste heat boiler；08, primary heater；09, secondary scrubber；10, reaction end gas Recyclable device；11, tail gas burns unit；12, extraction tower；13, azeotropic distillation device；14, first-stage reactor feed preheater； 15, second reactor；16, oxidizing and crystallizing unit；17, filter element is aoxidized；18, material-compound tank is aoxidized；19, filtrate cooling vacuum mistake Filter system；20, oxidation residua processing unit；21, material-compound tank is refined；22, preheater；23, hydrogenator；24, refining crystallization Unit；25, refining filtering unit；26, drying unit is refined；27, it is vented purifying column；28, cleaning solution heater；29, second level adds Hot device；30, waste heat recovery plant.

Specific embodiment

The present invention will be further illustrated below in conjunction with specific embodiments.It should be understood that these embodiments are merely to illustrate this Utility model rather than limitation the scope of the utility model.In addition, it should also be understood that, in the content for having read the utility model instruction Later, those skilled in the art can make various changes or modifications the utility model, and such equivalent forms equally fall within this Shen It please the appended claims limited range.

As shown in Figure 1, the embodiments of the present invention is related to a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection, packet Oxidation section and refinement are included, the oxidation section includes the first-stage reactor 01 to connect with external compression air and second level Reactor 15, the first-stage reactor 01 connect tail gas washing tower 02, and tail gas washing tower 02 connects heat recovery boiler 03, should Tail gas washing tower 02 is to wash the organic matters such as the PT carried secretly in tail gas acid, paraxylene, methyl acetate, the heat recovery boiler 03 is connected with level-one mixing, washing tower 04, and the level-one mixing, washing tower 04 is connect with waste heat boiler 07, waste heat boiler 07 with Primary heater 08 is connected, and waste heat boiler 07 is connected with first-stage reactor feed preheater 14 with primary heater 08, described First-stage reactor feed preheater 14 be connected respectively with first-stage reactor 01 and azeotropic distillation device 13, the level-one is mixed It closes scrubbing tower 04 to be connected by mixture pump 06 with first-stage reactor 01, the primary heater 08 is separately connected second level washing Tower 09, extraction tower 12, azeotropic distillation device 13 and secondary heater 29, the second reactor 15 and oxidizing and crystallizing unit 16 It is connected, the oxidizing and crystallizing unit 16 is connected with oxidation filter element 17, the oxidation filter element 17 and refinement It is connected.

The oxidation section further includes the cyclonic separation being connected with level-one mixing, washing tower 04 and first-stage reactor 01 Device 05, the hot waste water of the external product containing fine particle of the cyclone separator 05 and intermediate product.

The secondary scrubber 09 is connected with reaction end gas recyclable device 10, the reaction end gas recyclable device 10 with Tail gas burns unit 11 and is connected.

The refinement includes the purification material-compound tank 21 being connected with oxidation filter element 17, the purification material-compound tank 21 are connected by several preheaters 22 with hydrogenator 23, are sequentially connected refining crystallization list after the hydrogenator 23 Member 24, refining filtering unit 25 and purification drying unit 26.

The refining crystallization unit 24 is connected with emptying purifying column 27, and the preheater 22 is filled with Waste Heat Recovery respectively Set 30 and secondary heater 29 be connected, the refining filtering unit 25 and the cleaning solution heater 28 for being used for heated scrub It is connected.

The oxidation filter element 17 is connected with filtrate cooling vacuum filtration system 19, filtrate cooling vacuum filtering system System 19 is connected with oxidation residua processing unit 20.

It is specific as follows as specific embodiment:

(a) oxidation operation:

Air compressor provides compressed air to first-stage reactor 01 and second reactor 15, aoxidizes the liquid of material-compound tank 18 It is fed after being heated by first-stage reactor feed preheater 14 to first-stage reactor 01, by the way that a certain proportion of cobalt, manganese, bromine is added Catalyst makes the catalyst of system reach suitable concentration, so as to adjust reaction degree and control reaction depth；It is anti-in oxidation Answer unit, first-stage reactor 01 and second reactor 15 using the method for different operation pressure, to reduce reaction process Central Plains The consumption of material, acetic acid；

The solvent vapo(u)r generated in first-stage reactor 01 is mixed with reaction end gas, enters tail gas by blow-down pipe Scrubbing tower 02 washs the organic matters such as paraxylene, the methyl acetate carried secretly in tail gas, solvent vapo(u)r and reaction end gas after washing Into 03 output low-pressure steam of heat recovery boiler, the hot waste water from refined unit by cyclone separator 05 processing after and Enter level-one mixing, washing tower 04 by uncooled solvent vapo(u)r after 03 energy regenerating of heat recovery boiler and reaction end gas, passes through Enter the different grades of steam of 07 output of waste heat boiler at different levels after mixing, washing, 04 tower bottom mixed liquor of level-one mixing, washing tower passes through Mixture pump 06 is delivered in first-stage reactor 01；

By after waste heat boiler 07 and uncooled solvent vapo(u)r and reaction end gas enter primary heater 08 and heat waste heat The liquid being condensed in boiler replenishing water, waste heat boiler 07 and primary heater 08 adds through first-stage reactor feed preheater 14 First-stage reactor 01, extraction tower 12 and azeotropic distillation device 13 are sent into after hot mixing charging, meanwhile, reaction end gas enters second level and washes Tower 09 is washed, in secondary scrubber 09, reaction end gas is sent after peracetic acid, desalination water washing to reaction end gas energy recycle device 10, the reaction end gas after energy regenerating, which enters tail gas and burns unit 11, to be ultimately discharged into atmosphere；

Oxidation slurry after first-stage reactor 01 and second reactor 15 control impurity concentration enters oxidizing and crystallizing unit 16, oxidation slurry enters oxidation filter element 17 after step pressure reducing, cooling in oxidizing and crystallizing unit 16, comes from oxidizing and crystallizing The crude terephthalic acid crystallization largely dissolved after unit 16 is precipitated, and the crude terephthalic acid product of precipitation is by filtering and washing After send to purification material-compound tank 21, filtrate and cleaning solution are delivered to by delivery pump and are aoxidized in material-compound tank 18.

(b) refining step:

The thick TA product come from oxidation unit is dense by being mixed into uniform slurry into purification material-compound tank 21 after addition water Moderate TA slurry is spent, the TA slurry dissolved in purification material-compound tank 21 after booster pump pressurization and the heating of preheated device 22 by sending Enter hydrogenator 23, the lime set that the heating period generates heats waste heat boiler moisturizing, hot fixed gas by secondary heater 29 It first passes through waste heat recovery plant 30 and generates high-grade steam, then heat 25 institute of refining filtering unit by cleaning solution heater 28 The Washing of Filter Cake liquid needed eventually enters into the hydrogen in waste heat recovery unit recycling exhaust gas；

By the suitable hydrogen of addition in hydrogenator 23, reduction reaction occurs after being sufficiently mixed it with slurry, PTA slurry after reaction enters refining crystallization unit 24, the preheated device 22 of the flash-off steam generated in refining crystallization unit 24 Its fixed gas enters emptying purifying column 27 after heat exchange, and entrainer heater is equipped in emptying purifying column 27 for heating azeotropic essence Entrainer used in distillation unit 13；Tail gas, which is sent into, through blower by the washing of emptying purifying column 27, purified gas burns unit 11。

In refining crystallization unit 24, by step pressure reducing, cooling so that PTA is precipitated from solvent and is sent into refining filtering Unit 25, by being sent after filtering and washing to purification drying unit 26, the steam evaporated in purification drying unit 26 is washed Tower heat exchanger heats PTA device auxiliary unit water, reduces energy consumption, and the PTA product after purification drying unit 26 is dry is final It is sent into Storage Silo.

In order to which except the impurity in 17 filtrate of deoxidation filter element, extraction section filtrate is sent cooling true to filtrate from filtrate Empty filtration system 19 is sent through cooling, filtered residue to oxidation residua unit 20, and oxidation residua is returned using complete molten method operation Cobalt, manganese Metal in receipts oxidation residua, reduce solid waste discharge, and waste water is discharged into sewage unit, and biogas is generated in anaerobism and is used as Fuel.

Claims (8)

1. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection, including oxidation section and refinement, the oxidation section packet Include the first-stage reactor (01) and second reactor (15) to connect with external compression air, which is characterized in that the level-one is anti- Device (01) is answered to connect tail gas washing tower (02), tail gas washing tower (02) connects heat recovery boiler (03), the heat recovery boiler (03) it is connected with level-one mixing, washing tower (04), the level-one mixing, washing tower (04) is connect with waste heat boiler (07), waste heat Boiler (07) is connected with primary heater (08), and waste heat boiler (07) and primary heater (08) are pre- with first-stage reactor charging Hot device (14) is connected, and the first-stage reactor feed preheater (14) is filled with first-stage reactor (01) and azeotropic distillation respectively It sets (13) to be connected, the level-one mixing, washing tower (04) is connected by mixture pump (06) with first-stage reactor (01), described Primary heater (08) be separately connected secondary scrubber (09), extraction tower (12), azeotropic distillation device (13) and second level heating Device (29), the second reactor (15) are connected with oxidizing and crystallizing unit (16), the oxidizing and crystallizing unit (16) and oxygen Change filter element (17) to be connected, the oxidation filter element (17) is connected with refinement.

2. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 1, it is characterised in that: the oxygen Chemical industry section further includes the cyclone separator (05) being connected with level-one mixing, washing tower (04) and first-stage reactor (01), the whirlwind The hot waste water of the external product containing fine particle of separator (05) and intermediate product.

3. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 1, it is characterised in that: described two Grade scrubbing tower (09) is connected with reaction end gas recyclable device (10), and the reaction end gas recyclable device (10) and tail gas burn list First (11) are connected.

4. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 1, it is characterised in that: the essence Workshop section processed includes the purification material-compound tank (21) being connected with oxidation filter element (17), and the purification material-compound tank (21) passes through several A preheater (22) is connected with hydrogenator (23), and the hydrogenator is sequentially connected refining crystallization unit after (23) (24), refining filtering unit (25) and purification drying unit (26).

5. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 4, it is characterised in that: the essence Crystalline element (24) processed is connected with emptying purifying column (27).

6. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 5, it is characterised in that: described is pre- Hot device (22) is connected with waste heat recovery plant (30) and secondary heater (29) respectively.

7. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 6, it is characterised in that: the essence Filter element (25) processed is connected with the cleaning solution heater (28) for heated scrub.

8. a kind of aromatic carboxylic acid's process units of energy-saving and environmental protection according to claim 4, it is characterised in that: the oxygen Change filter element (17) to be connected with filtrate cooling vacuum filtration system (19), the filtrate cooling vacuum filtration system (19) and oxidation Residue treatment device (20) is connected.