CN210001582U

CN210001582U - Low-moisture-content hydrogen chloride synthesis system

Info

Publication number: CN210001582U
Application number: CN201920846132.4U
Authority: CN
Inventors: 苏永学; 刘宝东; 张兆云; 桑兆虎; 张国林; 王增强; 李学伟; 马志超; 杜建军; 李友光; 牛应东; 赵丽颖; 肖国营; 周少强; 范月生; 周智川; 吴红志; 刘川; 徐建玲; 崔小英
Original assignee: TANGSHAN SANYOU CHLOR-ALKALI Co Ltd
Current assignee: TANGSHAN SANYOU CHLOR-ALKALI Co Ltd
Priority date: 2019-06-05
Filing date: 2019-06-05
Publication date: 2020-01-31
Anticipated expiration: 2029-06-05

Abstract

The utility model provides an kind of low moisture content hydrogen chloride synthesis system, its structure is that set up hydrogen processing apparatus on original chlorine chloride synthesis system's hydrogen is responsible for, be responsible for hydrogen and divide into anterior segment high water oxygen hydrogen and be responsible for, the back end purifies hydrogen and is responsible for, it is continuous with the synthetic furnace to purify hydrogen and be responsible for, be provided with chlorine processing apparatus on chlorine is responsible for, be responsible for chlorine and divide into anterior segment oxygen-containing chlorine and be responsible for, the back end purifies chlorine and is responsible for, it is continuous with the synthetic furnace to purify chlorine and be responsible for, this system has still designed multiple self-loopa, reciprocating treatment reaches that the adsorption tower switches steadily, system's pressure fluctuation is controllable, give vent to anger oxygen, the purpose up to standard of water, the hydrogen chloride gas water oxygen content of the.

Description

Low-moisture-content hydrogen chloride synthesis system

Technical Field

The utility model belongs to a hydrogen chloride production technology, in particular to an low-moisture hydrogen chloride synthesizer.

Background

Most of chlor-alkali enterprises are equipped with hydrogen chloride synthesis and calcium carbide VCM synthesis processes, hydrogen chloride and acetylene are converted into vinyl chloride under the action of mercury chloride catalysts, and addition reaction is carried out on the vinyl chloride and the water content of a mixed gas of the hydrogen chloride and the acetylene is less than 600PPm (v/v), so that deep cooling dehydration is required to be carried out, and then the mixed gas enters a downlink process, energy is wasted, the requirement on frequent dehydration cannot be met, and the like, meanwhile, because a hydrogen system is subjected to pressure-increasing operation by using a water ring compressor, the water content is high, condensed water is always separated out in a pipeline for the hydrogen to enter a synthesis furnace, so that flow instability, instrument failure and the like are caused, and in addition, because of the existence of oxygen, a large amount of water is generated in the synthesis process and is stored at the bottom of the synthesis furnace, adverse effects are caused on a lamp cap and the like of the synthesis furnace, the instability of system proportion and fluctuation influence on the stability of a chlorine hydrogen treatment system, and even chain electrolysis shutdown caused by DCS judgment failure.

The contents of the utility model

The utility model discloses aim at solving the problem that the air feed water content and the gained product water content are high in the synthetic production process of hydrogen chloride, propose production systems that can effectively reduce production moisture, its concrete scheme is:

A hydrogen chloride synthesizing system with low water content is composed of water ring compressor, hydrogen gas source, back pipe connected to burner of synthesizing furnace, chlorine gas main pipe connected to gas outlet of concentrated sulfuric acid dewatering equipment and connected to burner of synthesizing furnace, hydrogen main pipe and chlorine gas main pipe with several control valves, hydrogen treating unit consisting of adsorption towers, drier, cooler and control valves, chlorine gas storage tank, buffer tank, and oxygen absorbing buffer tank.

The device is provided with a processing device in the middle section of the hydrogen main pipe and the chlorine main pipe respectively, and multiple self-circulation is designed in the processing device, so that the purposes of stable switching of the adsorption tower, controllable system pressure fluctuation, gas outlet oxygen-containing and water-containing reaching standards are achieved in a reciprocating manner. Ensuring that the oxygen content of the hydrogen supplied to the synthesis furnace reaches the standard.

Drawings

FIG. 1 is a schematic diagram of a hydrogen chloride synthesis system of the present invention;

FIG. 2 is a diagram of a hydrogen PSA apparatus;

FIG. 3 is a diagram of a chlorine pressure swing adsorption unit.

Detailed Description

The design of the utility model is that, to chlorine, hydrogen treatment before hydrogen and chlorine converge into house steward, get rid of hydrogen normal water and oxygen, get rid of the oxygen in the chlorine, improve the hydrogen and the chlorine purity that supply the synthetic furnace, reach the problem branch that the hydrogen chloride gas water content of control synthetic furnace burning preparation also can obtain fine control.

The existing hydrogen chloride synthesis system structure comprises a water ring compressor 1, wherein a front position pipe is connected with a hydrogen gas source, a rear position pipe is connected with a synthesis furnace 12 combustor through a hydrogen main pipe, the end of a chlorine main pipe is connected with the outlet of concentrated sulfuric acid dehydration equipment 9, the end of the chlorine main pipe is connected with the synthesis furnace 12 combustor, and a plurality of control valves 5 are arranged on the hydrogen main pipe and the chlorine main pipe.

The existing synthesis process is to directly introduce hydrogen and chlorine into a burner from a gas source, and then dehydrate and deoxidize hydrogen chloride extracted from the top of the burner to obtain a hydrogen chloride product. In the process, because the hydrogen source gas contains a large amount of water and oxygen, and the chlorine gas contains a large amount of oxygen even though the chlorine gas is dehydrated by concentrated sulfuric acid, and the impurities of the supplied gas are all more, the water content of the hydrogen chloride extracted from the top of the synthesis furnace is directly large, and the hydrogen chloride needs to be treated at a large cost to obtain a qualified product. In particular, when the hydrogen gas is supplied to the synthesis furnace at a designed ratio due to a large water content in the supplied hydrogen gas, accidents such as furnace shutdown and the like caused by inaccurate ratio and water content in the pipeline are caused.

The utility model discloses make great transformation to current synthesis system, it is shown with accompanying figure 1-3 specifically to be: 1) the hydrogen main pipe is provided with a hydrogen processing device 3 which is divided into a front high-water hydrogen oxygen main pipe 2 and a rear purified hydrogen main pipe 4; 2) the chlorine main pipe is provided with a chlorine gas treatment device 7, and the chlorine main pipe is divided into a front-stage oxygen-containing chlorine main pipe 8 and a rear-stage purified chlorine main pipe 6.

The utility model provides a hydrogen processing apparatus 3 is hydrogen temperature and pressure changing dehydration, deoxidation device, and it includes a plurality of adsorption towers 31, desicator 33, cooler 32 and some control valves .

The hydrogen gas source is respectively connected to the adsorption towers 31 through the water ring compressor 1, the adsorption towers 31 are connected in parallel between the main high-hydrogen-oxygen pipe 2 and the main purified hydrogen pipe 4, the adsorption towers 31 can be mutually standby, and the towers are also provided with connected pipelines and can be mutually switched. An adsorbent is arranged in the adsorption tower 31 and used for adsorbing water and oxygen in the hydrogen, and the adsorption tower is also provided with an emptying pipe.

The drier 33 side is connected with the purified hydrogen main pipe 4 through a branch pipe 34, the introduced part of purified hydrogen is heated, the heating medium of the drier 33 is introduced steam, the outlet of the heated hydrogen is connected with the adsorbent chamber of the adsorption tower 31, the hydrogen is heated in the drier 33, the hot hydrogen flows through the adsorbent, the moisture in the adsorbent is vaporized and carried out of the adsorption tower 31, the moisture adsorbed by the adsorbent is removed, the small branch flow of the dehydration hydrogen main pipe is provided with a valve for controlling the flow rate.

The refrigerant of the cooler 32 is cooling water with the temperature of 5 ℃; the cooler is connected with the adsorbent chamber of the adsorption tower 31 by a cooling medium inlet, the cooled medium gas phase outlet is connected with the front position pipe of the water ring compressor 1, and the liquid phase outlet is connected with the water storage tank. The cooler 32 cools the hydrogen with water at high temperature, so that the high-temperature saturated water contained in the hydrogen is liquefied and separated, and the low-temperature hydrogen with lower water content returns to the pipeline in front of the water-ring compressor 1 and is merged into the hydrogen treatment process again.

Each connecting pipe in the hydrogen processing device is provided with a control valve 5.

The utility model provides a chlorine processing apparatus 7 includes a plurality of adsorption towers 71, buffer tank 10 and useless chlorine absorption system 11 for pressure swing adsorption equipment. The adsorption towers 71 are connected in parallel between the main oxygen-containing chlorine pipe 8 and the main purified chlorine pipe 6, and the adsorption towers 71 can be used for each other, and are provided with pipelines connected with each other to realize switching. The adsorption tower 71 is provided with an adsorbent for adsorbing oxygen in the chlorine gas. The adsorption tower 71 is connected with a buffer tank 10, and the buffer tank 10 is connected with a waste chlorine treatment system 11.

The process of the chlorine gas treatment device 7 for treating the chlorine gas is as follows: chlorine gas is introduced into the adsorption tower 71, the adsorbent 71 adsorbs oxygen in the chlorine gas, clean chlorine gas is supplied to the burner through the purified chlorine main pipe, when the adsorption is nearly saturated and the oxygen content in the adsorbed outlet gas is about to fail to meet the index requirement, the adsorption tower 71 carries out reverse discharge operation, and oxygen-enriched waste chlorine gas in the adsorbent is discharged.

The treatment method of the low-moisture-content hydrogen chloride synthesis system comprises the following steps:

, a, supplying hydrogen into a hydrogen main pipe under pressure by a water ring compressor, cooling at 5 ℃ and filtering by fibers and conveying the hydrogen to a burner of a synthesis furnace, arranging a hydrogen treatment device in front of a control valve of the hydrogen main pipe to carry out dehydration and deoxidization treatment on a hydrogen gas source, specifically, introducing the hydrogen into each adsorption tower respectively, adsorbing water and oxygen in the hydrogen by an adsorbent in the adsorption tower, conveying the hydrogen to the burner of the synthesis furnace by a purified hydrogen main pipe after the adsorbed gas reaches the water and oxygen content of the hydrogen and the oxygen content is reduced to be below 100PPm, carrying out reverse releasing operation on the adsorption tower when the adsorption is close to saturation and the oxygen content of the adsorbed gas is not up to the index requirement, discharging the oxygen in the adsorbent to the atmosphere, carrying out the adsorption operation and the reverse releasing operation alternately for standby, and introducing heated purified hydrogen into the adsorbent to carry out temperature rise and vaporization and removal.

b. The chlorine is dehydrated by a concentrated sulfuric acid dehydration system and is conveyed to a burner of the synthesis furnace through a chlorine main pipe. The front path of the chlorine main pipe control valve is provided with a chlorine treatment device for carrying out deoxidization treatment on a chlorine gas source. The specific treatment is as follows: respectively introducing chlorine into each adsorption tower, adsorbing oxygen in the chlorine by using an adsorbent in the adsorption tower, and conveying the chlorine to a synthesis burner through a purified chlorine main pipe after the oxygen content of the chlorine is reduced to be less than 100PPm by the adsorbed outlet gas; when the adsorption is close to saturation and the oxygen content in the adsorbed gas is about to fail to meet the index requirement, the adsorption tower performs reverse discharge operation, the oxygen-enriched waste chlorine in the adsorbent is discharged and subjected to harmless treatment, and the adsorption operation and the reverse discharge operation of each adsorption tower are performed in a staggered mode and are mutually standby.

And secondly, setting the opening degree of control valves on the hydrogen main pipe and the chlorine main pipe, and supplying the processed hydrogen and chlorine to the burner of the synthesis furnace in proportion.

And thirdly, combusting chlorine and hydrogen in a synthesis furnace to generate hydrogen chloride, extracting hydrogen chloride gas from the top of the synthesis furnace, condensing water vapor generated by combustion by using a cooling device in the synthesis furnace, and extracting condensed water from the bottom of the synthesis furnace.

The water content of the hydrogen chloride product finally synthesized by the method (namely the gas extracted from the furnace top) is lower than 500PPm, and the hydrogen chloride product can be directly used without dehydration and deoxidation treatment.

In the hydrogen treatment device, when water and oxygen adsorbed by the single-tower adsorbent are nearly saturated and the adsorbed gas is about to fail to meet the index requirement, the adsorption tower carries out reverse discharge operation. The specific reverse releasing process is as follows: the first half of the reverse-releasing operation is that hydrogen in the adsorption tower is released to the adsorption tower to be put into use, the pressure of the reverse-releasing adsorption tower is reduced, the pressure of the tower to be put into use is increased until the two towers reach the equal pressure; the second half is reversed, and a small amount of residual hydrogen, oxygen adsorbed in the adsorbent and part of water which are not discharged out sequentially in the tower are discharged through an emptying pipe. The hydrogen is adsorbed and discharged without pollution and is directly discharged to the atmosphere. The adsorption tower to be put into use is firstly put in the forward direction and then put in the reverse direction, and the forward-discharge gas can pressurize the adsorption tower to be put into use, so that the adsorption tower to be put into use is prevented from being suddenly involved in an adsorption system to interfere with fluctuation on the adsorption system.

The reverse discharge process of the chlorine treatment device comprises the following steps: when the adsorption tower 71 is reversely placed, the pressure in the tower is reduced, chlorine gas is firstly placed in the adsorption tower 71 to be put into use, and the pressure equalization of the two towers is the first half; the latter half is reversed to discharge the oxygen-enriched waste chlorine in the adsorbent, and the gas can pollute the atmosphere and cannot be directly discharged to the atmosphere, and the discharged gas is sent to a waste chlorine absorption system 11 through a buffer tank 10 for harmless treatment.

The buffer tank 10 is responsible for collecting waste chlorine generated by the liquid chlorine system and oxygen-enriched waste chlorine (collectively referred to as waste chlorine) generated by the pressure swing adsorption, and after being buffered and stabilized, the outlet of the buffer tank is connected with a waste chlorine absorption system to carry out harmless treatment on the waste chlorine.

According to the reverse release process, the adsorption process and the purification process of the adsorbent are completed by the cooperation of the adsorption towers, and the adsorption work and the reverse release work of the adsorption towers are performed in a staggered manner. In the adsorption towers, one tower which is about to be put into operation after drying is firstly used as an intermediate buffer to receive gas with low water content and oxygen which is discharged out of the adsorption tower about to be reversely discharged, and then the finished gas is gradually supplemented to finally reach the system pressure so as to be smoothly transferred into the adsorption tower later.

Claims

A hydrogen chloride synthesizing system with low water content is composed of hydrogen main pipe connected to hydrogen source and back position pipe connected to burner of synthesizing furnace, chlorine main pipe connected to gas outlet of concentrated sulfuric acid dewatering equipment and connected to burner of synthesizing furnace, and several control valves for said main pipes.