CN202643597U

CN202643597U - Dimethyl oxalate removing device of hydrogenation reactor sub-line in production of coal-made ethylene glycol

Info

Publication number: CN202643597U
Application number: CN 201220177429
Authority: CN
Inventors: 段巍
Original assignee: Anhui Huaihua Co Ltd
Current assignee: Anhui Huaihua Co Ltd
Priority date: 2012-04-24
Filing date: 2012-04-24
Publication date: 2013-01-02
Anticipated expiration: 2022-04-24

Abstract

The utility model relates to dimethyl oxalate removing device of a hydrogenation reactor sub-line in production of coal-made ethylene glycol. The dimethyl oxalate removing device is characterized in that an absorption groove is arranged in the hydrogenation reactor sub-line, and the groove is provided with fine methyl alcohol from the outside. By means of the dimethyl oxalate removing device, in the halt, emergency halt and abnormal production states in the hydrogenation reaction process of the industrialized production of the coal-made ethylene glycol, the absorption groove in the sub-line can timely absorb and recover dimethyl oxalate for recycle and the phenomenon that the dimethyl oxalate is brought into a hydrogenation reactor and subsequent refining systems can be effectively avoided. Thus, the dimethyl oxalate removing device has great practical value.

Description

The hydrogenator by-pass removes the dimethyl oxalate device in the coal-ethylene glycol production

Technical field

The utility model relate to a kind of be applicable in the production of industrialization coal-ethylene glycol hydrogenation process stop, stop in emergency and improper production status under, prevent that dimethyl oxalate from bringing the device of hydrogenator and follow-up refining system into.

Background technology

The coal-ethylene glycol industrial manufacture process is mainly in two steps at present:

One, esterification and oxonation:

2CH ₃OH+N ₂O ₃＝2CH ₃ONO+H ₂O

2CO+2CH ₃ONO＝(COOCH ₃)2+2NO

Two, hydrogenation reaction:

(COOCH ₃)2+4H ₂＝(CH ₂OH)2+2CH ₃OH

The physical properties of dimethyl oxalate: clear, colorless can be dissolved in pure and mild ether to little yellow liquid.Be slightly soluble in cold water, in hot water, decompose.

Relative density: 1.1479 (54 ℃)

Fusing point: 54 ℃

Boiling point: 163～164 ℃ (0.101MPa)

The shortcoming of existing Technology situation and existence:

As seen from Figure 1, under existing Technology situation, dimethyl oxalate forms mixed gas with high-purity hydrogen and enter the hydrogenator generating glycol behind main line valve Q1, hydrogenation reaction preheater after heater heats to 150 ℃.Under the normal condition of production, main line valve Q1 opens, and by-pass valve Q2 closes.In production abnormal condition and system shutdown, the situation of stopping in emergency, existing coal-ethylene glycol technique is taked following two kinds of methods at present:

One, there is not the hydrogenator by-pass, gas mixture enters hydrogenator by the dimethyl oxalate well heater through the hydrogenation reaction preheater, the consequence that this operational path causes is, dimethyl oxalate in the mixing tank can condense at the hydrogenation catalyst device, so that activity of hydrocatalyst declines to a great extent, and dimethyl oxalate can be brought into follow-up refining system through after the condensation, and in the finished product ethylene glycol in case contain dimethyl oxalate and will bring the ethylene glycol quality product and seriously influence, be in particular in the indexs such as the colourity of ethylene glycol and ultraviolet transmittance.

Two, as shown in Figure 1, the situation that the hydrogenator by-pass is arranged, production abnormal condition and system shutdown, in the situation of stopping in emergency, then take to close main line valve Q1, open the method for by-pass valve Q2, although methyl alcohol and dimethyl oxalate gas mixture can be without hydrogenators, but still can enter into follow-up refining system by condenser, equally the ethylene glycol product is impacted, in normal production, the ball valve Q2 on the hydrogenator by-pass leaks in a single day occuring, and can't close fully simultaneously, with so that a large amount of gas mixtures enters into refining system through Q2, ethylene glycol quality product and follow up device equipment are brought serious consequence.

The utility model content

The technical problem that the utility model solves provide a kind of be applicable in the production of industrialization coal-ethylene glycol hydrogenation process stop, stop in emergency and improper production status under, prevent that dimethyl oxalate from bringing the device of hydrogenator and follow-up refining system into.

The hydrogenator by-pass removes the dimethyl oxalate device in a kind of coal-ethylene glycol production, and it is to add an absorption cell in the hydrogenator by-pass, and extraneous next refined methanol is housed in the groove.

Device of the present utility model, its a kind of preferred embodiment is: comprise the dimethyl oxalate well heater, hydrogenation reaction preheater, hydrogenator, condenser, and absorption cell; Described dimethyl oxalate well heater has dimethyl oxalate import and hydrogen inlet, and the mixing of two gas enters the hydrogenation reaction preheater by valve control, enters hydrogenator after the preheating, enters condenser after having reacted, and this is the hydrogenator main line; The hydrogenator by-pass is after the dimethyl oxalate well heater, and by the import that the absorption cell of refined methanol is equipped with in the valve connection, the outlet of absorption cell is connected to the exit of hydrogenator through valve.

Device of the present utility model, in the production of industrialization coal-ethylene glycol hydrogenation process stop, stop in emergency and improper production status under, can in time dimethyl oxalate be absorbed recycling by the absorption cell on the by-pass, prevent that effectively dimethyl oxalate from bringing the device of hydrogenator and follow-up refining system into.Have great practical value.

Description of drawings

Fig. 1 is the synoptic diagram of prior-art devices;

Fig. 2 is the synoptic diagram of the utility model device.

Embodiment

For further specifying the utility model, specify with the following Examples:

As shown in Figure 2, the hydrogenator by-pass removes the dimethyl oxalate device in a kind of coal-ethylene glycol production, comprises dimethyl oxalate well heater 1, hydrogenation reaction preheater 2, hydrogenator 3, condenser 4, and absorption cell 5; Dimethyl oxalate well heater 1 has dimethyl oxalate import and hydrogen inlet, and the mixing of two gas enters hydrogenation reaction preheater 2 by valve Q1 control, enters hydrogenator 3 after the preheating, enters condenser 4 after having reacted, and this is the hydrogenator main line; The hydrogenator by-pass is after dimethyl oxalate well heater 1, and by the import that the absorption cell 5 of refined methanol is equipped with in valve Q2 connection, the outlet of absorption cell 5 is connected to the exit of hydrogenator 3 through valve Q3.

Under the normal production status, open hydrogenator main line valve Q1, close hydrogenator by-pass valve Q2, Q3.In production abnomal condition and parking, the situation of stopping in emergency, close hydrogenator main line valve Q1, open hydrogenator by-pass valve Q2, Q3, allow gas mixture through absorption cell, enter condenser, utilize dimethyl oxalate to be dissolved in the characteristic of alcohol, sponge the dimethyl oxalate in the gas mixture, prevent that it is brought into refining system.When the dimethyl oxalate content in the absorption cell reaches 30%-40%, the methyl alcohol in the absorption cell, dimethyl oxalate mixed solution can be driven into the utilization of again gasifying of dimethyl oxalate well heater, by hydrogenation reaction (COOCH ₃) ₂+ 4H ₂=(CH ₂OH) ₂+ 2CH ₃OH can find out that the methyl alcohol, the dimethyl oxalate mixed solution that join in the dimethyl oxalate well heater can not bring any impact to hydrogenation reaction and follow-up refining system.

Above-described embodiment is described preferred implementation of the present utility model; be not that scope of the present utility model is limited; under the prerequisite that does not break away from the utility model design spirit; various distortion and improvement that the common engineering technical personnel in this area make the technical solution of the utility model all should fall in the definite protection domain of claims of the present utility model.

Claims

1. the hydrogenator by-pass removes the dimethyl oxalate device in the coal-ethylene glycol production, it is characterized in that: add an absorption cell in the hydrogenator by-pass, the extraneous refined methanol that comes is housed in the groove.

2. device according to claim 1, it is characterized in that: described device comprises dimethyl oxalate well heater (1), hydrogenation reaction preheater (2), hydrogenator (3), condenser (4), and absorption cell (5); Described dimethyl oxalate well heater (1) has dimethyl oxalate import and hydrogen inlet, the mixing of two gas enters hydrogenation reaction preheater (2) by valve (Q1) control, enter hydrogenator (3) after the preheating, enter condenser (4) after having reacted, this is the hydrogenator main line; The hydrogenator by-pass is at dimethyl oxalate well heater (1) afterwards, by the import that the absorption cell (5) of refined methanol is equipped with in valve (Q2) connection, the outlet of absorption cell (5) is connected to the exit of hydrogenator (3) through valve (Q3).