CN203095915U

CN203095915U - Device for reducing content of methyl alcohol in silver-method methanol process

Info

Publication number: CN203095915U
Application number: CN2013200849936U
Authority: CN
Inventors: 景玉国
Original assignee: HEBEI KAIYUE CHEMICAL INDUSTRIAL Co Ltd
Current assignee: HEBEI KAIYUE CHEMICAL INDUSTRIAL Co Ltd
Priority date: 2013-02-26
Filing date: 2013-02-26
Publication date: 2013-07-31
Anticipated expiration: 2023-02-26

Abstract

The utility model relates to a device for reducing content of methyl alcohol in a silver-method methanol process, and belongs to the technical field of chemical industry production. The technical scheme is as follows: the device comprises an air filter (1), a blower (2), a methanol evaporator (3), a ternary heater (4), an oxidation reactor (5) and an absorption tower (6) which are sequentially arranged, wherein a concentration evaporator (7) is arranged between an outlet of the oxidization reactor and an inlet of the absorption tower; and a vacuum groove (8) is formed in a methanol liquid extracting port at the bottom of the absorption tower. According to the device, the heat recovery efficiency of a system is improved while the temperature of the inlet of the absorption tower is reduced; the load of a water cooler of the absorption tower is reduced, the consumption of cooling water is reduced, 100 percent of classification recycling of residual liquid is realized, and the recycled methanol has no phenomenon of backmixing, and the aims of energy conservation, consumption reduction and environment protection are fulfilled.

Description

Reduce the device of methanol content in the silver Division A League Matches of French Football aldehyde technology

Technical field

The utility model relates to the device that reduces methanol content in a kind of silver-colored Division A League Matches of French Football aldehyde technology, belongs to chemical production technical field.

Background technology

At present, Formaldehyde Production mainly contains Yin Fa and two kinds of technologies of iron molybdenum method, and silver-colored Division A League Matches of French Football aldehyde technology is compared advantage such as have less investment, power consumption is low with iron molybdenum method technology, be widely used.But shortcoming such as silver-colored Division A League Matches of French Football aldehyde technology has, and the methyl alcohol unit consumption is higher, methanol content height in the formaldehyde products, concentration of formaldehyde are lower; People have adopted several different methods that silver-colored Division A League Matches of French Football aldehyde technology is improved, and for example adopt tail gas circulation method, flue gas recirculation method, dilute methanol liquid circulation method, dealcoholize column etc. is set, but all fundamentally do not state solution.Above-mentioned technological improvement has just solved a certain shortcoming wherein, but has brought following new problem simultaneously again.1. adopt tail gas or flue gas recirculation method technology, concentration of formaldehyde improves, but power current consumption obviously increases the not tangible reduction of material benzenemethanol consumption; 2. dealcoholize column is set, China Patent No. 200920024869.4 described 80-85 ℃ of the control dealcoholize column temperature that need, cause the heat recovery rate of system to descend because of temperature is higher, the higher parsing amount of formaldehyde that causes of Yin Wendu is bigger simultaneously, contain more formaldehyde in the methanol gas that reclaims, do not reach the boiling temperature of formaldehyde solution though the dealcoholysis temperature is higher, the dealcoholysis effect is relatively poor, because of the evaporator evaporation temperature lower, this part formaldehyde major part enters in the vaporizer raffinate, contain more formaldehyde and methyl alcohol in the vaporizer raffinate, raffinate is not effectively reclaimed, caused waste, simultaneously environment has been caused pollution, material benzenemethanol consumption does not significantly reduce, and the methanol stripper effect is restricted; 3. adopt dilute methanol liquid circulation method technology, China Patent No. 201110158755.0, described with the absorption tower hypomere as dealcoholize column, the dilute methanol that epimere reclaims enters vaporizer, the problem that exists is with that dealcoholize column is set separately is close, the dealcoholize column temperature is higher, the heat recovery efficiency that is unfavorable for improving system because of temperature is higher, do not reach the boiling temperature of formaldehyde solution equally though the dealcoholysis temperature is higher, the dealcoholysis effect is relatively poor, and simultaneously the formaldehyde content in the dilute methanol is higher, because of the evaporator evaporation temperature lower, the more methyl alcohol and the formaldehyde that contain equally in the vaporizer raffinate, be recovered to the dealcoholize column bottom, the methyl alcohol in the raffinate has turned back to again in the formaldehyde solution, has methyl alcohol back-mixing problem, methanol content in the formaldehyde products does not significantly reduce, and material benzenemethanol consumption does not significantly descend yet.

The utility model content

The purpose of this utility model provides the device that reduces methanol content in a kind of silver-colored Division A League Matches of French Football aldehyde technology, and responseless methyl alcohol in the formaldehyde is separated under lower temperature, and the methanol gas of recovery and air mixed turn back in the unstripped gas; Utilize residual heat of reaction that the vaporizer raffinate is carried out evaporation concentration under higher temperature, methyl alcohol wherein is evaporated to gas with water and turns back in the unstripped gas, liquids recovery after concentrating is to the absorption tower, the methyl alcohol that reclaims all turns back in the unstripped gas of Formaldehyde Production, in reducing formaldehyde products in the methanol content, reduce material benzenemethanol consumption, improve concentration of formaldehyde, solve the problems referred to above that exist in the background, reach the purpose of energy-conservation, consumption reduction, environmental protection.

The purpose of this utility model is achieved in that

Reduce the device of methanol content in the silver Division A League Matches of French Football aldehyde technology, comprise air filter, blower fan, methanol evaporator, ternary well heater, oxidation reactor and the absorption tower arranged successively, between oxidation reactor outlet and absorption tower import, concentration evaporator is set; Formaldehyde liquid extraction mouth is provided with vacuum tank in the bottom, absorption tower.

The vacuum tank liquid-inlet is connected with bottom, absorption tower formaldehyde liquid extraction mouth, and the outlet of vacuum tank top gas is connected with the blower fan import.

Concentration evaporator is continuous evaporator or vaporizer intermittently; The thermal source of methanol evaporator adopts steam, hot water or absorption tower circulation fluid.

Described raffinate is meant the liquid that contains components such as methyl alcohol, water of methanol evaporator bottom discharging.

Described vaporizer is meant methanol evaporator, is composite evaporation device or single methanol evaporator.

Bottom, the absorption tower methyl alcohol weight percent content of silver Division A League Matches of French Football aldehyde technology is the formaldehyde liquid of 0.5-5.0%, after the recovery of heat cooling, quantitatively extraction enters vacuum tank, methyl alcohol weight percent content in the formaldehyde liquid that discharge the vacuum tank bottom is transported to the product storage tank less than 0.5% as formaldehyde products, and the gas that resolve at the vacuum tank top contains water vapour, methanol steam and a small amount of formaldehyde gas and is transported to the air blower import; Simultaneously, between oxidation reactor outlet and absorption tower import, concentration evaporator is set, utilize residual heat of reaction that the raffinate of methanol evaporator is carried out evaporation concentration under 90-110 ℃ of condition, methyl alcohol in the raffinate evaporates with water, water vapour and methanol steam mixed gas are recovered in the unstripped gas, the methyl alcohol weight percent content is recovered to the absorption tower less than 0.5% in the raffinate after concentrating, when reducing the absorption tower inlet temperature, improves system's heat recovery efficiency.

The formaldehyde fluid temperature that enters vacuum tank is 50-70 ℃, and the residence time of formaldehyde liquid in vacuum tank is 5-30 minute, and control vacuum tank pressure is the 0.1-60KPa(absolute pressure).Mainly contain three kinds of components such as water, formaldehyde and methyl alcohol in the formaldehyde liquid, wherein the water weight percent accounts for 50-70%, and in above-mentioned three kinds of components, the boiling point of methyl alcohol is minimum, and only under boiling state, the vaporization velocity of separation and the separating effect of methyl alcohol component could improve; Under normal pressure, 80-90 ℃ condition, do not reach boiling state; Because of vacuum tank pressure is low, formaldehyde liquid can reach boiling state under lower temperature; Resolve the isolating while in the methyl alcohol component, a part of water and a small amount of formaldehyde gasify thereupon and are gas, and because of the amount of formaldehyde gasification is very little, the concentration of formaldehyde obviously improves.

Described concentration evaporator is arranged between oxidation reactor outlet and the absorption tower import, utilize reaction gas 110-160 ℃ waste heat that the raffinate of methanol evaporator is carried out concentration and evaporation, contain water in the raffinate of methanol evaporator, methyl alcohol and a small amount of formaldehyde, the boiling point of methyl alcohol component is minimum, equally only under boiling state, the vaporization velocity of separation and the separating effect of methyl alcohol component could improve, in the raffinate because of methanol evaporator, the ratio that water accounts for is the highest, up to the 70-90%(weight percent), at normal pressure, temperature is lower than under 90 ℃ of conditions and is difficult to reach boiling state, under the normal pressure, temperature must reach more than 90 ℃ just can reach boiling state.

The utility model is provided with vacuum tank and concentration evaporator, the vacuum tank liquid-inlet is connected with bottom, absorption tower formaldehyde liquid extraction mouth, the outlet of vacuum tank top gas is connected with the blower fan import, 50-70 ℃ formaldehyde liquid of bottom, absorption tower formaldehyde liquid extraction mouth extraction is in vacuum tank, utilize the temperature of self, in the 0.1-60KPa(absolute pressure) under the condition, formaldehyde liquid reaches boiling state, realize that methyl alcohol resolves gasification and reclaim and turn back in the unstripped gas as the raw material of Formaldehyde Production, the formaldehyde liquid behind the separation of methanol is transported to the product storage tank as formaldehyde products; Concentration evaporator utilizes reaction gas as thermal source, be arranged between oxidation reactor outlet and the absorption tower import, be connected by pipeline, the raffinate that methanol evaporator is discharged is in concentration evaporator, utilize the Formaldehyde Production residual heat of reaction at normal pressure, will methyl alcohol evaporation wherein under 90-110 ℃ of condition reclaim the raw material that turns back in the unstripped gas as Formaldehyde Production, most of water in the raffinate also is evaporated to water vapour thereupon simultaneously, reduced the temperature of absorption tower import reaction gas, improved the heat recovery efficiency of system, reduced absorption tower water cooler load, and then reduced cooling-water consumption, realized raffinate 100% classification recovery, the methyl alcohol that reclaims does not have air-teturning mixed phenomenon, reaches energy-conservation, consumption reduction, the purpose of environmental protection.

Description of drawings

Fig. 1 is the utility model embodiment one synoptic diagram;

Fig. 2 is the utility model embodiment two synoptic diagram;

Among the figure: air filter 1, blower fan 2, methanol evaporator 3, ternary well heater 4, oxidation reactor 5, absorption tower 6, concentration evaporator 7, vacuum tank 8, ternary strainer 9, recirculation heater 10, vacuum pump 11.

Embodiment

Below in conjunction with accompanying drawing,, the utility model is described further by embodiment.

Embodiment 1: see accompanying drawing 1 for details, the utility model is applied to adopt the silver-colored Division A League Matches of French Football aldehyde production technique of composite evaporation device, and methanol evaporator is the composite evaporation device.

Concrete technical process is: air is through air filter, enter the composite evaporation device by the blower fan pressurization, the composite evaporation device adopts absorption tower one tower circulation formalin as thermal source, in the composite evaporation device, the mixing liquid of first alcohol and water contacts with air, at normal pressure, gas evaporation forms water vapour under the 60-70 ℃ of condition, methanol steam, air three-element mixed gas body, make up water and pass through the temperature raising of ternary well heater again behind the steam, temperature is elevated to 110-120 ℃, enter oxidation reactor through the ternary strainer, at 600-650 ℃, under the effect of silver catalyst, methyl alcohol carries out oxidative dehydrogenation and generates formaldehyde, reacted gas is through the supporting rapid-cooling heat exchanger of oxidation reactor, temperature drops to 130-140 ℃ and enters concentration evaporator, the reaction gas temperature drops to 100-110 ℃ and enters the absorption tower, water and reaction gas counter current contact in the absorption tower, formaldehyde gas is absorbed by water and is converted to formaldehyde liquid, responseless methyl alcohol is absorbed by water simultaneously and is mixed in the formaldehyde liquid, three sections absorptions are adopted on the absorption tower, the tail gas that discharge at the top, absorption tower recycles, 70-80 ℃ of the formaldehyde fluid temperature that discharge the bottom, absorption tower, the methyl alcohol weight percent content is that 1.2-1.5% enters the composite evaporation device and carries out recovery of heat, temperature drops to 50-70 ℃, a part is got back to absorption tower one tower circulation and is absorbed, quantitatively extraction part formaldehyde liquid enters the vacuum tank dealcoholysis, control vacuum tank pressure 10-20KPa(absolute pressure), liquid in vacuum tank residence time 10-15 minute, methyl alcohol weight percent content in the formaldehyde liquid that discharge the vacuum tank bottom is transported to the product storage tank less than 0.2% as formaldehyde products, the gas that resolve at the vacuum tank top contains water vapour, methanol steam and a small amount of formaldehyde gas are transported to the air blower import by vacuum pump, turn back to that the raw material as Formaldehyde Production uses in the ternary gas.

The raffinate that discharge composite evaporation device bottom, the main component weight percent is: water 60-70%, methyl alcohol 20-40%, formaldehyde 3-5%, enter concentration evaporator, under normal pressure, 95-105 ℃ condition, carry out evaporation concentration, methyl alcohol in the raffinate evaporates with water, water vapour and methanol steam mixed gas are recovered in the unstripped gas of evaporator outlet, and weight percent in the raffinate after concentrating: water-content 70-80%, formaldehyde content 10-20%, methanol content are recovered to the absorption tower less than 0.2%.

Embodiment 2: see accompanying drawing 2 for details, the utility model is applied to adopt the silver-colored Division A League Matches of French Football aldehyde production technique of common vaporizer, and vaporizer is single methanol evaporator.

Main flow process is identical with embodiment 1, difference is: vaporizer is single methanol evaporator, the vaporization temperature 70-80 of methanol evaporator ℃, vaporization temperature is higher than the composite evaporation device, and methanol evaporator bottom raffinate component weight percent is: water 70-80%, methyl alcohol 20-30%.

Claims

1. reduce the device of methanol content in the silver-colored Division A League Matches of French Football aldehyde technology, it is characterized in that: comprise successively the air filter (1) arranged, blower fan (2), methanol evaporator (3), ternary well heater (4), oxidation reactor (5) and absorption tower (6), oxidation reactor export and the absorption tower import between concentration evaporator (7) is set; Formaldehyde liquid extraction mouth is provided with vacuum tank (8) in the bottom, absorption tower.

2. reduce the device of methanol content in the silver-colored Division A League Matches of French Football aldehyde technology according to claim 1, it is characterized in that: the vacuum tank liquid-inlet is connected with bottom, absorption tower formaldehyde liquid extraction mouth, and the outlet of vacuum tank top gas is connected with the blower fan import.

3. reduce the device of methanol content in the silver-colored Division A League Matches of French Football aldehyde technology according to claim 1 and 2, it is characterized in that: concentration evaporator is continuous evaporator or vaporizer intermittently.

4. reduce the device of methanol content in the silver-colored Division A League Matches of French Football aldehyde technology according to claim 1 and 2, it is characterized in that: described methanol evaporator is composite evaporation device or single methanol evaporator.