CN1012560B

CN1012560B - Improved isothermal reaction furnace

Info

Publication number: CN1012560B
Application number: CN 87103900
Authority: CN
Inventors: 唐国平
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-05-27
Filing date: 1987-05-27
Publication date: 1991-05-08
Also published as: CN87103900A

Abstract

The present invention relates to an isothermal reaction furnace, particularly to a novel improved isothermal reaction furnace formed by the combination of an isothermal reactor and an adiabatic reactor. The present invention is suitable for using ethyl benzene and diethylbenzene as raw materials to produce styrene monomer, divinylbenzene, etc. The present invention has the advantages of high total conversion rate, high yield and energy saving. Because a reaction section is added and the production quantity can be increased obviously, the present invention is suitable for the production of styrene monomer and divinylbenzene with various scales.

Description

Improved isothermal reaction furnace

The present invention relates to isothermal reaction furnace, specifically, it is a kind of novel improved isothermal reaction furnace that the isothermal reaction furnace of ethylbenzene, diethylbenzene combines with the adiabatic reaction stove and forms, and same, it also is applicable to other production field.

In Chemical Manufacture, the manufacturing of styrene, divinylbenzene is that employing ethylbenzene, diethylbenzene are raw material, in the reactor of catalyst is housed, carries out catalytic dehydrogenating reaction under high temperature, generates styrene, divinylbenzene, and its key reaction formula is:

Above-mentioned dehydrogenation reaction is mainly carried out in isothermal reaction furnace or adiabatic reaction stove.

Isothermal reaction furnace is made up of combustion chamber, reactor, superheater, preheater, heat exchanger, steam superheater and ethylbenzene evaporimeter etc.When ethylbenzene or diethylbenzene carry out the isothermal catalytic dehydrogenation by reactor, it is fewer to react used dilution steam generation, react required heat and be the width of cloth that utilizes fuel combustion to produce penetrate heat and advection heat by with isothermal reaction furnace in the tube wall of reactor carry out heat exchange, provide reaction required heat, make the temperature up and down of heating region equal substantially, so be called isothermal reaction furnace, general annual production is adopted the device of the type mostly in the styrene of the middle-size and small-size scale below 5000 tons, the production of divinylbenzene.

The adiabatic reaction stove generally is used for fairly large production, and it is made up of steam superheater, blender, adiabatic reactor and resuperheater etc.Dehydrogenation reaction is carried out in adiabatic reactor, and reactor is the drum type brake fixed bed reactors, in the tube catalyst is housed, not heat supply separately in conversion zone, and its reaction institute calorific requirement all relies on the sensible heat of superheated steam to provide.

Above-mentioned two kinds of reacting furnaces all are to enter reactor by ethylbenzene, diethylbenzene and mixture of steam through being raised to predetermined temperature after the heat exchange repeatedly, and dehydrogenation reaction takes place under the catalytic action of catalyst.Isothermal reaction furnace is because the dilution steam generation that reacts used is less, and the heat that reacts required will lean on the width of cloth of fuel combustion to penetrate heat and advection heat provides, and has therefore limited the production scale of constant-temperature oven; The adiabatic reaction stove needs steam superheater, the superheated vapour of a large amount of consumes energy to enter the adabatic dehydrogenation reactor by resuperheater, blender again, and Btu utilization is lower.Simultaneously, the conversion ratio of above-mentioned isothermal reaction furnace and adiabatic reaction stove and yield are also lower.

In order fully rationally to utilize heat energy, fortifying catalytic effect, to improve the conversion ratio and the yield of styrene, divinylbenzene, the invention provides a kind of novel improved isothermal reaction furnace that isothermal reaction furnace combines with the adiabatic reaction stove and additional combustion chamber superheater.

The object of the present invention is achieved like this: improved isothermal reaction furnace comprises: combustion chamber, superheater, preheater, blender, heat exchanger is characterized in that being combined into improved isothermal reactor and combustion chamber superheater by isothermal reactor and adiabatic reactor.

Advantage of the present invention is tangible, at first can rationally utilize heat energy, improve yield and conversion ratio, owing in burner hearth, set up combustion chamber superheater, the temperature of inlet feed temperature and outlet material is tapped into, help bringing into play the effect of upper strata catalyst like this, and because the import and export material temperature difference is little, might be chosen in catalytic selectivity optimal reaction temperature reaction, thereby reduce greatly and controlled side reaction, improve conversion ratio and yield.And the isothermal reactor outlet material that can utilize improved isothermal reactor top is about 600 ℃, than the high characteristics of import thing temperature, can satisfy the requirement of feeding temperature of the adiabatic reactor of improved isothermal reactor bottom, save, save fuel the material energy of heating separately.Simultaneously, ethylbenzene, the diethylbenzene of the isothermal reactor catalytic dehydrogenating reaction by top enter the lower thermal barrier reactor that catalyst is housed once again and further carry out catalytic dehydrogenating reaction, because the catalyst of bottom insulate heat reactor charge, then the ability of catalytic reaction can improve greatly.Simultaneously because reaction mass directly enters the lower thermal barrier reactor from the top isothermal reactor, be to participate in reaction once, therefore avoided the repeatedly circulation in reactor of ethylbenzene, diethylbenzene, thereby reduced supplies consumption, improved reaction conversion ratio and yield greatly from technology.Adopt that this technology total conversion can improve about 10%, yield can improve about 5%, simultaneously, owing to increase conversion zone (but also multistage), input amount increases, and then output increases, so this technology is applicable to the styrene of various scales, the production of divinylbenzene.

Below, incite somebody to action in conjunction with the accompanying drawings and most preferred embodiment, the present invention is described in further detail, but embodiment limits the present invention.

Accompanying drawing 1 is the structural representation of the improved isothermal reaction furnace of the present invention.

Accompanying drawing 2 is the structural representation of the improved isothermal reactor of the present invention.

As shown in Figure 1, improved isothermal reaction furnace comprises that combustion chamber superheater [2], top that combustion chamber [1], high-temperature steel tube material are made are that calandria type fixed bed isothermal reactor [4] and bottom are improved isothermal reactor [29], steam superheater [5], ethylbenzene preheater [6], blender [7], heat exchanger [8], the steam superheater compositions such as [9] that drum type brake fixed bed adiabatic reactor [3] is formed.

The flow process of material is as follows: water vapour is heated to about 200 ℃ in steam superheater [9], entering stove outer heat-exchanger [8] again reaches about 400 ℃ through the heat exchange water vapor (steam) temperature, enter preheater [6] at blender [7] and ethylbenzene or diethylbenzene gaseous mixture, enter superheater [5] tube side again, reach 480 ℃-500 ℃ by flue gas heating back mixture temperature, pass through combustion chamber superheater [2] again, after 780 ℃ of-800 ℃ of flue gas heating, make the ethylbenzene of participating in dehydrogenation reaction, the diethylbenzene mist reaches 540 ℃ of-560 ℃ of temperature of expection, because flue gas directly heats and has saved thermal energy consumption, enter in the calandria type fixed bed isothermal reactor in top [4] tubulation of improved isothermal reactor catalyst is housed, ethylbenzene, diethylbenzene carries out catalytic dehydrogenating reaction, mist temperature after the dehydrogenation reaction reaches about 580 ℃-610 ℃, enter the bottom drum type brake fixed bed adiabatic reactor [3] of improved isothermal reactor again, the sensible heat that required heat of reaction itself is brought into through reacted mist by top isothermal reactor [4] provides, the further like this heat energy of having saved, at this moment, be under the effect of the catalyst of mist in lower thermal barrier reactor [3] of high temperature, further carry out dehydrogenation reaction, like this, strengthened catalytic action greatly, as the catalytic amount on the layer bed of bottom adiabatic reactor [3] be in the tubulation of top isothermal reactor catalytic amount 50%, then the ability of catalytic reaction can improve about 50%.Simultaneously, it is disposable participation reaction that the mist of participation reaction enters lower thermal barrier reactor [3] at the top of improved isothermal reactor isothermal reactor [4], therefore avoided the repeatedly circulation in reactor of unreacted ethylbenzene, diethylbenzene, thereby greatly reduced supplies consumption from technology.Adopt that the total conversion of this technology styrene, divinylbenzene can improve about 10%, total recovery can improve about 5%.Simultaneously, owing to increase by one section conversion zone, (but also multistage), and input amount increases, and then output increases, so applicable to the styrene of various production scales, the production of divinyl.

As shown in Figure 2, improved isothermal reactor comprises that the main pressurized element material is band gas inlet tube a and the temperature-measuring port b that 1 Crl8 Ni9Ti makes, the upper cover of pressure tap c [13], be arranged between upper perforated plate [23] and the lower perforated plate [18] in respect of 90 tubulations [10] that catalyst is housed, link with stationary pipes [24] between the last lower perforated plate, upper cover [13] links with flange [11] with upper perforated plate [23], lower perforated plate [18] links by bolt [19] and catalyst supporting plate [16], catalyst supporting plate [16] is by support plate [28] supporting, form top isothermal reactor [4], have deflection plate [22] up and down on the reactor [4], [22 '], and reactor [4] is fixed on support ring [25] in the burner hearth, support ring [26] and gusset [27]; And lower thermal barrier reactor [3] by the reducer [15] of the pipe nipple [20] of the low head [14] of band gas outlet tube d and temperature-measuring port e, pressure tap f, low head [14] and isothermal reactor [4] by flange [17] link, device catalyst supporting plate [21], supporting plate [21] support by support plate [12] on pipe nipple [20] cylindrical shell, can loading catalyst on the supporting plate [21].

Above-mentioned improved isothermal reactor has one deck catalyst plate [21] at least and forms one section layer bed formula adiabatic reactor [3], or has multilayer catalyst supporting plate [21] composition multistage layer hearth reactor [3]; Top isothermal reactor [4] and lower thermal barrier reactor [3] can fuse by flange [17]; Top isothermal reactor [4] and lower thermal barrier reactor [3] also can be provided with separately, link by pipe; And with the quantity of the lower thermal barrier reactor [3] of top isothermal reactor [4] coupling can be more than one.

Claims

1, a kind of ethylbenzene that is used for, the diethylbenzene catalytic dehydrogenation prepares styrene, the reacting furnace of divinylbenzene, the isothermal reactor [4] that contains combuster [1] and connect successively by pipeline, superheater [5], preheater [6], blender [7], heat exchanger [8], steam superheater [9], it is characterized in that described isothermal reactor [4] is to use flange [17] and pipe nipple [20] to link by the reducer [15] of isothermal reactor [4], at pipe nipple [20] cylindrical shell position device catalyst supporting plate [21], supporting plate [21] is by support plate [12] supporting, supporting plate [21] is gone up the isothermal reactor of adiabatic reactor [3] combination of placing catalyst, and described isothermal reactor [4] is a calandria type fixed bed reactor, adiabatic reactor [3] is the drum type brake fixed bed reactors; And the superheater [2] that is arranged on burner hearth is connected with the upper end of isothermal reactor [4] with superheater [5] by pipeline.

2, reacting furnace as claimed in claim 1 is characterized in that adiabatic reactor [3] has the supporting plate [21] of one deck catalyst at least, also can have the supporting plate [21] of multilayer catalyst, forms one or more snippets layer bed formula adiabatic reactor [3].

3, reacting furnace as claimed in claim 1 or 2 is characterized in that and adiabatic reactor [3] that isothermal reactor [4] is combined into one can be one or more snippets layer bed formula adiabatic reactor [3].

4, reacting furnace as claimed in claim 1 or 2 is characterized in that isothermal reactor [4] and adiabatic reactor [3] are setting separately separately, and is communicated with composition by the outlet of isothermal reactor [4] and the inlet tube of adiabatic reactor [3].

5, reacting furnace as claimed in claim 4 is characterized in that and the adiabatic reactor [3] of isothermal reactor [4] coupling is one or more snippets layer bed formula adiabatic reactor [3].

6, reacting furnace as claimed in claim 1 or 2, it is characterized in that reactor [4] comprises band gas inlet tube a, temperature-measuring port b, the upper cover of pressure tap c [13], the tubulation [10] that catalyst is housed is arranged between lower perforated plate [18] and the upper perforated plate [23], lower perforated plate [18] and upper perforated plate [23] link with stationary pipes [24], upper cover [13] links with flange with upper perforated plate [23], lower perforated plate [18] links by bolt [19] and catalyst supporting plate [16], catalyst supporting plate [16] is by support plate [28] supporting, isothermal reactor [4] is provided with lower flap portion [22], [22 '], and by support ring [25], support ring [26] and gusset [27] are fixed in the burner hearth; Lower thermal barrier reactor [3] comprises that the reducer [15] by the pipe nipple [20] of being with gas outlet tube d and temperature-measuring port e, pressure tap f and low head [14], low head [14] and isothermal reactor [4] links, upward places catalyst at pipe nipple [20] cylindrical shell position device catalyst supporting plate [21], supporting plate [21] by support plate [12] supporting, supporting plate [21] by flange [17].