CN2738876Y - Quenching mixer with annular flow-channel in exothermic reactor - Google Patents

Abstract

The utility model provides a quenching mixer with an annular flow-channel in the exothermic reactor, and comprises inlets 1 and 2, flow channels 3, 4, 6, 7, a centering box body 10 and an outlet 12. Wherein the flow channels 3 and 4 are communicated with the flow channel 7 at a flow cutting opening 5; the flow channel 7 is communicated with the centering box body 10 at a flow cutting opening 8; baffles 6 and 9 which control the logistics flowing direction are respectively installed in the flow channel 7 and the centering box body 10; the periphery of the outlet 12 is provided with one ring damper 11; the lower part of the outlet 12 is provided with a circular baffle 15 fixed by a connection strip 17. The quenching mixer can mix sufficiently the reaction logistics of the high temperature and the supplemented cold medium, reduces radical temperature difference at next one entrance of the catalyst bed layer, and is good to sufficiently display the catalyst activity and the selectivity.

Description

The quench mixer that has annular runner in a kind of exothermic reactor

Technical field

The utility model relates to the interior a kind of member of reactor of a speciogenesis exothermic reaction, specifically a kind of reaction logistics and the additional well-mixed quench mixer of cold medium that can realize heat.

Background technology

Exothermic reaction is very general in petroleum refining and petrochemical process process, as hydrocracking reaction, hydrofining reaction and alkylated reaction etc. all are exothermic reactions, in some exothermal reaction process, if the temperature of reaction logistics is not controlled, catalyst in reactor bed temperature inside just might rise rapidly at short notice, and reach unmanageable degree, common " temperature runaway " phenomenon of indication that Here it is, therefore the thermal discharge when reaction is bigger, when the temperature rise of beds is higher, regulate and control the temperature of reaction logistics and what prevent " temperature runaway " phenomenon is very necessary by suitable cooling means.The heat-obtaining mode that can Gong select for use generally has non-direct heat-obtaining and directly adds the cooling medium dual mode, then a kind of mode is the better method that adopts usually, promptly the beds in the reactor is divided into two with upper bed layer, inner member is set between adjacent two beds and replenishes cold medium, reaching fully mixing of cold medium and thermal response logistics, and can be distributed to equably in next beds.

With the hydrogenation reaction is example, usually pass through beds with gas phase or gas, liquid two-phase in the logistics of hydrogenation reactor internal reaction, and exothermic reactions such as hydrocracking reaction, hydrofining reaction take place, in order to control the temperature of reaction logistics, prevent to take place in the beds " temperature runaway " phenomenon, usually cold medium is joined between two adjacent beds, and in the inner member of reactor with on the thermal response logistics that comes of a beds mix fully, and be distributed to equably in next beds.Mix logistics radially the position be very necessary with the top that the temperature and the composition of homogeneous enters next beds, because reaction stream temperature and composition gradient radially can further be aggravated owing to the carrying out of reaction, finally might cause hot-spot in the beds, improve and the selectivity reduction in hot-spot place activity of such catalysts, carbon deposit on the catalyst increases fast, particularly evident in hydrocracking process, this can cause the too early inactivation of catalyst, and because action of high temperature, the physical property of catalyst carrier is damaged, thereby causes the premature aging of catalyst.The inhomogeneous density of hydrogen of a certain part that also can make of reactant flow distribution is on the low side, and accelerates the carbon deposit speed of catalyst herein, and then the selectivity and the conversion ratio of influence reaction.

In hydrogenation reactor, the inner member between adjacent two beds generally comprises: cold medium inlet tube, quench mixer, pre-distribution grid and distribution grid.The effect of cold medium inlet tube is that the cold medium that temperature is lower is introduced in the reactor, be generally the structures such as straight tube, a shape pipe or loop pipe that have the rectangle perforate, cold medium is evenly sprayed by the opening of inlet tube, enter quench mixer with a last beds after next preliminary mixing of thermal response logistics, cold medium is generally the lower hydrogen of temperature, gaseous stream or liquid phase stream; The effect of quench mixer is to make the cold medium of introducing and the reaction logistics of heat realize the balance of mass transfer and heat transfer within it as far as possible, makes temperature and composition gradient in liquid phase or the gas phase very little; The effect of pre-distribution grid is that the mixture stream that comes out from quench mixer is distributed in advance, and arrives distribution grid, and pre-distribution grid is generally the sieve tray structure; The effect of distribution grid is to make to mix the top that logistics is distributed to next beds equably, and it is the platy structure of allocation units that distribution grid is generally with the bubble cap.

In hydrogenation process, the inner member of reactor mixes with the cold homogeneous media of replenishing except the reaction logistics with the heat of making and is evenly distributed to the effect of next beds, and the height of inner member also should be low as far as possible.Because the hydrogenation reactor great majority are high-pressure reactor, the diameter of reactor is big and wall is thicker, and a plurality of beds are arranged generally, also just need many group inner members, so the reduction of inner member height can make the total height of reactor reduce, thereby save the investment of reactor manufactured materials, and bring convenience for the transportation and the installation of reactor, can also save the investment of body supporting construction.

Quench mixer is the important component part of exothermic reactor inner member, the thermal response logistics that a last beds comes out mixes in quench mixer fully with the cold medium that replenishes into, in order to strengthen mixed effect, on the structural design of quench mixer, generally adopt the mechanism of throttling, collision and eddy flow.The quench mixer that US3502445 proposes is that gas-liquid two-phase enters in the quench mixer through two throttle orifices on the collecting board, after the head-on collision of gas-fluid two-phase mixture stream process, is divided into two-way and goes out quench mixer.This structure has obtained extensive use on commercial plant, but its mixed effect is unsatisfactory, thereby causes radial temperature difference bigger in the bed.CN2294771Y and CN2448440Y have proposed the quench mixer of different structure respectively, but concluded, the two all is that gas-fluid two-phase mixture stream is divided into two-way, just near two bursts of logistics that separate the quench mixer outlet just merge together, and go out quench mixer in the mode of eddy flow.This gas-fluid two-phase mixture stream is divided into two strands method, gas-liquid two-phase in the per share logistics is mixed, but because two bursts of logistics separating are shorter the time of contact after converging, inhomogeneities between two bursts of logistics can cause the heterogeneity of chilling case outlet stream temperature, thereby make the reaction logistics can not enter next beds with the temperature of homogeneous, has significantly radial temperature difference in the porch of next beds, this significantly radial temperature difference along with the carrying out of reaction also can further increase, and then influences the performance of catalyst performance in beds.In addition, the complex structure of above-mentioned quench mixer is made and the installation difficulty.

The utility model content

The purpose of this utility model provides the quench mixer that has annular runner in a kind of exothermic reactor, this quench mixer makes additional cold medium and conducts heat fully within it and mass transfer from the pyroreaction logistics of a last beds, and mix, thereby avoid in next beds because the reaction logistics mixes localized hyperthermia that inequality causes increasing suddenly carbon deposit on the infringement of catalyst physical property and the catalyst with cold medium.

The quench mixer structure that the utility model provides is as follows: quench mixer is by inlet 1 and 2, runner 3,4,7, core case 10, outlet 12 constitutes, wherein runner 3 and 4 communicates with runner 7 at throttle orifice 5 places, and runner 7 communicates with core case 10 at throttle orifice 8 places, is respectively equipped with the baffle plate 6 and 9 of control stream flow direction in runner 7 and core case 10, one ring-type weir 11 is arranged around the outlet 12, and the bottom of outlet 12 is the circular baffle plate 15 of fixing with connection strap 14.

The quench mixer that the utility model provides can be realized fully mixing of pyroreaction logistics and the cold medium that replenishes, and reduces the radial temperature difference of next beds inlet, helps catalyst activity and optionally gives full play to.

Description of drawings

Overlooking and fragmentary cross-sectional view of the quench mixer that Fig. 1 provides for the utility model, Fig. 2 is that A-A among Fig. 1 is to view.

The specific embodiment

Catalyst in the exothermic reactor is divided into a plurality of beds, be provided with one group of inner member in the space between the adjacent bed, the medium that the temperature of replenishing is lower is realized fully mixing in quench mixer with the pyroreaction logistics that a last beds comes, and has adopted mechanism such as throttling, collision, reinforcement mixing and eddy flow on the structure of quench mixer.The mixture flow point does not enter by two inlets of quench mixer, enter the interior annular runner through two bursts of logistics behind the segment distance through collision intensely and through throttle orifice, the flow direction that the baffle plate limit fluid is arranged in the annular channel, fluid by annular channel is in throttle orifice enters core case, the logistics that has baffle plate to make in the core case to enter via throttle orifice tangentially flows, mix logistics and in core case, form eddy flow, and flow out by center drilling, after the baffle plate interception and carrying out initial distribution, arrive the pre-distribution grid of quench mixer bottom.For the mixing of strengthening fluid in quench mixer, in the annular channel of quench mixer, baffle plate, throttle orifice or hybrid element such as corrugated plate, flight etc. can be set.

Below in conjunction with accompanying drawing the quench mixer that the utility model provides is given further instruction, but therefore do not limit the utility model.

Overlooking and fragmentary cross-sectional view of the quench mixer that Fig. 1 provides for the utility model, Fig. 2 is that A-A among Fig. 1 is to view.

The quench mixer structure that the utility model provides is as follows: quench mixer is by inlet 1 and 2, runner 3,4,7, core case 10, outlet 12 constitutes, wherein runner 3 and 4 communicates with runner 7 at throttle orifice 5 places, and runner 7 communicates with core case 10 at throttle orifice 8 places, is respectively equipped with the baffle plate 6 and 9 of control stream flow direction in runner 7 and core case 10, one ring-type weir 11 is arranged around the outlet 12, and the bottom of outlet 12 is the circular baffle plate 15 of fixing with connection strap 14.Cross section as the runner 3,4,7 of quench mixer part is a square or rectangular.

The quench mixer method of operating that the utility model provides is as follows:

As shown in Figure 1, quench mixer is placed on the liquid phase collecting board 13, seal between the outer rim of liquid phase collecting board 13 and the reactor wall, the thermal response logistics that a last beds comes does not enter quench mixer by the inlet 1 and 2 of quench mixer with the mixture flow point of the cold medium that replenishes, two bursts of logistics flow to throttle orifice 5 through runner 3 and 4 respectively, after taking place to collide intensely and mix, the two bursts of logistics in throttle orifice 5 places enter annular channel 7, in annular channel 7, there are baffle plate 6 limit fluid to flow in the same direction, mix logistics and enter core case 10 at throttle orifice 8 places, baffle plate 9 in the core case 10 makes fluid tangentially enter core case, mix logistics and in core case 10, realize eddy flow, and arrive the pre-distribution grid of bottom by outlet 12.Pre-distribution grid is a sieve-plate structure, in order to prevent that liquid phase from exporting 12 places at quench mixer and too flowing to the pre-distribution grid of bottom in the concentrated area, is provided with circular baffle plate 15 in the exit of quench mixer.

Fig. 2 be A-A among Fig. 1 to view, also be the sectional view of quench mixer along center line, the runner of quench mixer is surrounded by the vertical ring baffle 16,17,18 and the upper cover plate 19 that are connected on the liquid phase collecting board 13.Outlet 12 centers in core case, one ring-type weir 11 is arranged around outlet 12, to guarantee in the core case certain liquid level height being arranged, below outlet 12, a circular baffle plate 15 is arranged, be fixed on the liquid phase collecting board 13 with connection strap 14, circular baffle plate 15 can have the effect of initial distribution to gas-liquid two-phase.

The quench mixer advantage that the utility model provides is as follows:

1, the quench mixer main body is box annular channel, and is simple in structure, is easy to processing and manufacturing.

2, mix logistics and entered by the entrance 1 and 2 of quench mixer after, take place to swash at throttle orifice 5 places Collide, liquid phase stream is shredded into littler drop strongly, is conducive to heat transfer and the biography of gas-liquid two-phase Matter, mix logistics in quench mixer except the collision that fluid is arranged, also have repeatedly throttling and Eddy flow in the core case, these all are conducive to the mixed effect of strengthening fluid in quench mixer.

3, in quench mixer, mix logistics mainly by common runner 7, and through common Core case 10 is finished the gas phase of mixing or gas-liquid two-phase arrives the bottom by common outlet pre-branch Fabric swatch. Because in quench mixer, mix logistics and mainly flow in common runner, this just can Avoiding because of after fluid is divided into the multiply logistics, the mixing that the difference that exists between the per share logistics causes is not Equal problem.

4, in the annular channel of quench mixer, can be provided with as baffle plate, throttle orifice or hybrid element, in order to strengthen the mixing of logistics.

5, the runner of quench mixer all is arranged on the interior liquid collecting board 13 of reactor, and can adopt the runner in rectangle cross section, and the spatial altitude of quench mixer is low, and the spatial altitude that takies reactor is little, thereby helps reducing equipment investment.

Claims (4)

1, the quench mixer that has annular runner in a kind of exothermic reactor, it is characterized in that this quench mixer is by inlet (1) and (2), runner (3), (4), (7), core case (10), outlet (12) constitutes, wherein locate to communicate with runner (7) at throttle orifice (5) in runner (3) and (4), runner (7) is located to communicate with core case (10) at throttle orifice (8), in runner (7) and core case (10), be respectively equipped with baffle plate (6) and (9) of control stream flow direction, one ring-type weir (11) is arranged around the outlet (12), and the bottom of outlet (12) is with the fixing circular baffle plate (15) of connection strap (14).

2,, it is characterized in that described cross section of fluid channel is a square or rectangular according to the quench mixer of claim 1.

3,, it is characterized in that installing baffle plate, throttle orifice or hybrid element additional in the described runner (7) according to the quench mixer of claim 1.

4,, it is characterized in that described inlet (1) and (2) both sides in the reactor center symmetry according to the quench mixer of claim 1.