Ethanolamine production system capable of regulating and controlling product proportion

Abstract

The utility model discloses an ethanolamine production system capable of regulating and controlling the product proportion, which belongs to the technical field of ethanolamine industrial production and is characterized in that ethylene oxide and ammonia water as raw materials enter an ethanolamine reactor, and ammonia and water are removed from reaction discharged materials through an ammonia still and a dehydrating tower; and feeding the residual materials into a monoethanolamine refining tower, a diethanolamine refining tower and a triethanolamine evaporator to respectively extract monoethanolamine, diethanolamine and triethanolamine products. In order to regulate and control the output proportion of triethanolamine, the system is independently provided with a triethanolamine reactor for controlling the proportion of diethanol amine and triethanolamine. Compared with a traditional production system, interference on an ethanolamine reactor is avoided, and meanwhile, higher conversion rate and lower energy consumption are achieved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of ethanolamine industrial production, specifically relates to a kind of ethanolamine production system of product proportion can be regulated. BACKGROUND

[0002] Ethanolamine is the general term of monoethanolamine, diethanolamine and triethanolamine product, and is widely used in surfactants, metal working fluid, polyurethane catalyst, pharmaceutical, dye, cosmetics and other aspects. In industry, ethanolamine production process is to use excess ammonia and ethylene oxide as raw materials to synthesize monoethanolamine, diethanolamine and triethanolamine, and then to obtain three kinds of ethanolamine products through ammonia evaporation and dehydration process and product refining process. The whole reaction is a cascade reaction, and the reaction process is as follows:

[0003]

[0004] The reaction of ammonia, monoethanolamine, diethanolamine and ethylene oxide has a competitive relationship, and the three products of monoethanolamine, diethanolamine and triethanolamine must exist simultaneously in the reaction system. How to regulate the proportion of the three products is the key point and difficulty in the industrial production of ethanolamine. In traditional industry, in order to reduce the proportion of diethanolamine and increase the proportion of triethanolamine, diethanolamine is returned to the ethanolamine reactor. This method has the following disadvantages: the conversion rate of diethanolamine is only 43-51%, the energy consumption is high, and the interference to the ethanolamine reactor is large. In order to explore the proportion regulation method of the three kinds of ethanolamine products, a new production system is proposed. SUMMARY

[0005] To achieve the above object, the utility model provides a kind of ethanolamine production system of product proportion can be regulated, including ethanolamine reactor, triethanolamine reactor, ammonia tower, flash tank, dehydration tower, monoethanolamine refining tower, diethanolamine refining tower, triethanolamine evaporator, vacuum system and ammonia gas absorption system, it is characterized by:

[0006] Raw material A, ethanolamine reactor, ammonia tower, flash tank, dehydration tower, monoethanolamine refining tower, diethanolamine refining tower and triethanolamine evaporator are sequentially connected by pipeline;

[0007] Dehydration tower, monoethanolamine refining tower, diethanolamine refining tower and triethanolamine evaporator are communicated with vacuum system through multi-air phase pipe;

[0008] Flash tank extends pipeline and is connected with ammonia gas absorption system, and ammonia gas absorption system is communicated with ethanolamine reactor and vacuum system by pipeline respectively;

[0009] Preferably, diethanolamine refining tower and triethanolamine reactor are connected by circulation pipe;

[0010] Preferably, the raw material B is communicated with the ethanolamine reactor and the triethanolamine reactor through pipes, respectively;

[0011] Preferably, the ammonia stripping tower is communicated with the ethanolamine reactor through a reflux pipe.

[0012] Preferably, waste water is taken from the side of the dehydration tower.

[0013] Preferably, waste gas is taken from the top of the ammonia gas absorption system.

[0014] Preferably, monoethanolamine is taken from the side of the monoethanolamine rectifying tower.

[0015] Preferably, diethanolamine is taken from the circulation pipe between the diethanolamine rectifying tower and the triethanolamine reactor.

[0016] Preferably, triethanolamine is taken from the side of the triethanolamine evaporator.

[0017] Preferably, the ethanolamine reactor feed comprises reaction raw material A and raw material B, wherein the raw material A is liquid ammonia or 30%-80% ammonia water, and the raw material B is ethylene oxide with a purity of 99.99%. After mixing, the raw material A and the raw material B enter the ethanolamine reactor to sequentially react to synthesize monoethanolamine, diethanolamine and triethanolamine.

[0018] Preferably, the ethanolamine reactor operates at a pressure of 4.5-6.2 MPaG and a temperature of 55-118℃. The reactor is provided with a jacket, and the heat generated in the reaction is removed by water circulation.

[0019] Preferably, the ammonia stripping tower is connected with the ethanolamine reactor, and the ammonia stripped out of the ammonia stripping tower is returned to the ethanolamine reactor after condensation.

[0020] Preferably, the flash tank is connected with the ammonia stripping tower, and the ammonia removed by the flash tank and the non-condensable gas from the vacuum system enter the ammonia gas absorption system.

[0021] Preferably, the ammonia gas absorption system uses water to absorb the materials in the ammonia and the non-condensable gas, and the absorbed materials are returned to the ethanolamine reactor, and the unabsorbed gas is treated as waste gas.

[0022] Preferably, the dehydration tower is connected with the flash tank, and the removed water is treated as waste water. Preferably, the operating pressure of the dehydration tower is 10-25 kPaA.

[0023] Preferably, the monoethanolamine rectifying tower is connected with the dehydration tower, and the purified monoethanolamine product with a purity of ≥99.9% is taken out by rectification.

[0024] ≥99.9% of the monoethanolamine product.

[0025] Preferably, the operating pressure of the monoethanolamine rectifying tower is 0.1-2 kPaA.

[0026] Preferably, the diethanolamine rectification tower is connected with a monoethanolamine rectification tower, and a diethanolamine product with a purity of ≥ 99.5% is obtained through rectification, and part of the diethanolamine product is sent to the triethanolamine reactor. Preferably, the operating pressure of the diethanolamine rectification tower is 0.1-0.8 kPaA.

[0027] Preferably, the triethanolamine evaporator is connected with the diethanolamine rectification tower, and a triethanolamine product with a purity of ≥ 99.0% is obtained.

[0028] Preferably, the triethanolamine evaporator is connected with the diethanolamine rectification tower, and a triethanolamine product with a purity of ≥ 99.0% is obtained.

[0029] Preferably, the operating pressure of the triethanolamine evaporator is 0.01-0.1 kPaA.

[0030] Preferably, the vacuum system provides a negative pressure environment for the dehydration tower, the monoethanolamine rectification tower, the diethanolamine rectification tower and the triethanolamine evaporator.

[0031] Preferably, the triethanolamine reactor feed includes diethanolamine and ethylene oxide, wherein the molar ratio of diethanolamine to ethylene oxide is 1.1-2:1, and the reaction generated material enters the diethanolamine rectification tower.

[0032] Preferably, the molar ratio of ammonia and ethylene oxide in the monoethanolamine reactor is 4.2-8.0, and the output ratio of monoethanolamine is 40%-53%.

[0033] Compared with the prior art, the technical effects and advantages of the present application are:

[0034] The present system separately sets up a triethanolamine reactor for controlling the ratio of diethanolamine and triethanolamine, avoiding interference with the monoethanolamine reactor. The triethanolamine reactor is set to increase the conversion rate of diethanolamine to 88-95% by adjusting the addition amount of diethanolamine and ethylene oxide, and the energy consumption of the diethanolamine rectification tower is reduced by 23-28%. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The present system is a system diagram.

[0036] In the figure: 1, raw material A; 2, raw material B; 3, monoethanolamine reactor; 4, ammonia evaporator; 5, flash tank; 6, dehydration tower; 7, ammonia gas absorption system; 8, monoethanolamine rectification tower; 9, diethanolamine rectification tower; 10, triethanolamine evaporator; 11, triethanolamine reactor; 12, vacuum system; 15, multi-air-phase pipe; 43, reflux pipe. DETAILED DESCRIPTION

[0037] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0038] Embodiment 1

[0039] Please refer to Figure 1 The ethanolamine production system capable of controlling product proportion comprises an ethanolamine reactor 3, a triethanolamine reactor 11, an ammonia distillation tower 4, a flash tank 5, a dehydration tower 6, a monoethanolamine rectifying tower 8, a diethanolamine rectifying tower 9, a triethanolamine evaporator 10, a vacuum system 12 and an ammonia absorption system 7, and the ethanolamine production system is characterized in that:

[0040] The raw material A1, the ethanolamine reactor 3, the ammonia distillation tower 4, the flash tank 5, the dehydration tower 6, the monoethanolamine rectifying tower 8, the diethanolamine rectifying tower 9 and the triethanolamine evaporator 10 are sequentially connected by pipelines;

[0041] The dehydration tower 6, the monoethanolamine rectifying tower 8, the diethanolamine rectifying tower 9 and the triethanolamine evaporator 10 are connected with the vacuum system 12 through a plurality of air phase pipes 15;

[0042] The flash tank 5 extends a pipeline to be connected with the ammonia absorption system 7, and the ammonia absorption system 7 is connected with the ethanolamine reactor 3 and the vacuum system 12 through pipelines;

[0043] The diethanolamine rectifying tower 9 and the triethanolamine reactor 11 are connected through a circulation pipe 19;

[0044] The raw material B2 is connected with the ethanolamine reactor 3 and the triethanolamine reactor 11 through pipelines respectively;

[0045] The ammonia distillation tower 4 is connected with the ethanolamine reactor 3 through a reflux pipe 43;

[0046] Waste water is collected from the side of the dehydration tower 6, waste gas is collected from the top of the ammonia absorption system 7, monoethanolamine is collected from the side of the monoethanolamine rectifying tower 8, diethanolamine is collected from the circulation pipe 19 between the diethanolamine rectifying tower 9 and the triethanolamine reactor 11, and triethanolamine is collected from the side of the triethanolamine evaporator 10.

[0047] Working principle; ethanol amine reactor 3 into the raw material A1 and raw material B2, ethanol amine reactor 3 discharge into the ammonia tower 4 steam out part of ammonia after condensation return to ethanol amine reactor 3, the remaining material through the flash tank 5 flash top remove the remaining ammonia into ammonia gas absorption system 7, ammonia gas absorption system 7 bottom material into the dehydration tower 6 remove the water in the feed, dehydration tower 6 tower material into a monoethanolamine refining tower 8 refining out of a monoethanolamine product, the remaining material into two ethanol amine refining tower 9 refining out of two ethanol amine product, the remaining material into three ethanol amine evaporator 10 steam out of three ethanol amine product. Among them, two ethanol amine part of the product into three ethanol amine reactor 3 and raw material B2 reaction, return to two ethanol amine refining tower 9.

[0048] In one embodiment, dehydration tower 6, a monoethanolamine refining tower 8, two ethanol amine refining tower 9, three ethanol amine evaporator 10 through the multi air phase pipe 15 and vacuum system 12 is connected, the non condensing steam generated by the vacuum system 12 and the ammonia flashed out of the top of the flash tank 5 into the ammonia gas absorption system 7, through water absorption, as waste gas treatment, the water solution after absorption into the ethanol amine reactor 3 as catalyst.

[0049] The said ethanol amine reactor 3 feed contains reaction raw material A1 and raw material B2. Among them, raw material A1 is liquid ammonia or 30%-80% ammonia water, the said raw material B2 is the purity of 99.99% ethylene oxide.

[0050] In one embodiment, ethanol amine reactor 3 operating pressure 4.5-6.2 MPaG, operating temperature 55-118 DEG C. Reactor is provided with jacket, through water circulation to remove the heat generated by the reaction.

[0051] In one embodiment, ammonia tower 4 and ethanol amine reactor 3 connection, ammonia tower 4 steam out of ammonia after condensation return to ethanol amine reactor 3.

Claims

1. A system for producing ethanolamines with controllable product ratio, comprising an ethanolamine reactor (3), a triethanolamine reactor (11), an ammonia stripping column (4), a flash tank (5), a dehydration column (6), a monoethanolamine rectifying column (8), a diethanolamine rectifying column (9), a triethanolamine evaporator (10), a vacuum system (12) and an ammonia absorption system (7), characterized in that: the raw material A (1), the ethanolamine reactor (3), the ammonia stripping column (4), the flash tank (5), the dehydration column (6), the monoethanolamine rectifying column (8), the diethanolamine rectifying column (9) and the triethanolamine evaporator (10) are connected in sequence by pipelines; the dehydration column (6), the monoethanolamine rectifying column (8), the diethanolamine rectifying column (9) and the triethanolamine evaporator (10) are connected with the vacuum system (12) by a multi-pass gas phase pipe (15); the flash tank (5) is connected with the ammonia absorption system (7) by an extension pipeline, and the ammonia absorption system (7) is connected with the ethanolamine reactor (3) and the vacuum system (12) by pipelines; the diethanolamine rectifying column (9) and the triethanolamine reactor (11) are connected by a circulation pipe (19); the raw material B (2) is connected with the ethanolamine reactor (3) and the triethanolamine reactor (11) by pipelines; and the ammonia stripping column (4) is connected with the ethanolamine reactor (3) by a reflux pipe (43). The ethanolamine reactor (3) is fed with the reaction raw material A (1) and the raw material B (2), the raw material A (1) is liquid ammonia or 30%-80% ammonia water, and the raw material B (2) is ethylene oxide with a purity of 99.99%. The ethanolamine reactor (3) operates at a pressure of 4.5-6.2 MPaG and a temperature of 55-118℃. ​ ​ ​ ​ 2. The system for producing ethanolamines with controllable product ratio according to claim 1, characterized in that: ​ 3. The system for producing ethanolamines with controllable product ratio according to claim 1, characterized in that: ​

Images