CN2538416Y - Circulation reactor for hydrocracking process of heavy oil suspension bed - Google Patents

Abstract

The utility model discloses a circulation reactor suitable for a heavy oil suspension bed hydrocracking process. The reactor adopts two upper and lower circulation cylinders, and the inner diameter and height of the upper circulation cylinder are larger than the inner diameter and height of the lower circulation cylinder. There is an annular hydrogen distributor inside and outside the lower circulation cylinder respectively. The opening ratio of the inner hydrogen distributor is higher, and the opening ratio of the outer hydrogen distributor is lower. The reactor is fully back-mixed, with uniform reaction temperature and high average gas holdup, which is beneficial to the reaction process. The unique hydrogen distribution and solid particle settling environment of this reactor is beneficial to the hydrogenation reaction of materials inside and outside the circulation cylinder, and is beneficial to reduce the residence time of solid particles in the reactor. Tests show that the reactor has higher light oil yield and lower gas and coke yield, no coke deposition, long-term operation, simple structure and low cost.

Description

A kind of circulation flow reactor that is used for heavy oil floating bed hydrocracking technology

The utility model belongs to a kind of PETROLEUM PROCESSING consersion unit, and it can be used for gas, liquid and the simultaneous course of reaction of solid three-phase.Be specially adapted to use heavy oil (reduced crude, decompression residuum, the consistency crude oil) hydrocracking process of suspended bed of low concentration, dispersed catalysts.

The present used reactor of suspension bed hydrogenation process in the world, mostly be the up-flow reactor that goes out on advancing under the material, interim coke discharging mouth has also been added in the bottom of the reactor that has, these reactors are applicable to the process of big (about 3～10%) of catalyst amount usually, as Canmet technology, or solid particle reaches tens percent coal dust and heavy oil and refines altogether and liquefaction process.In the hydrocracking process of suspended bed of heavy oil, heavy oil has burnt the generation when being cracked into lighter hydrocarbons, light oil.Under the situation that has a large amount of catalyst or pulverized coal particle to exist, Jiao who generates in the course of reaction can be attached on catalyst or the pulverized coal particle, and discharge outside the reactor with it, even there is part temporarily can not be discharged from, because the existence of a large amount of catalyst and solid particle, they can not be gathered into big coke button mutually yet, finally also can discharge outside the reactor with material.But using low concentration (as the amount of metal of catalyst less than 0.5%), dispersed catalysts (metallic salt solution, organo-metallic compound, or their mixture is dispersed in the heavy oil) the heavy oil floating bed hydrocracking process in, even Jiao that reaction generates measures not very big (as 1%), burnt amount has been a large amount of with respect to the amount of catalyst, because the burnt grain that generates is the comparison thickness, if can not in time discharge outside the reactor, in the hot environment in reactor, be deposited on the burnt grain of reactor bottom, will be agglomerated into piece together with the catalyst granules of high dispersive, can't discharge reactor the most at last, and with reactor plugs.

For Jiao who generates being discharged outside the reactor, can improve the linear velocity of liquid material in the reactor, so that Jiao is given rise to the outlet on reactor top.And improve the method for liquid linear velocity, adopt the method for circulating pump usually.This circulating pump that utilizes is extracted liquid material out from reactor top, squeeze into reactor lower part then, improves the method for liquid linear velocity, still exists problem.Owing in course of reaction, need hydrogen to be mixed with feedstock oil, and mix to such an extent that the complete reaction effect is good more more by the hydrogen distributor.When from the top of reactor material being squeezed into the bottom with circulating pump, need be with hydrogen and oily the separation, the gas that contains in the material is few more, then the easy more raising pump speed of circulating pump.And feedstock oil mixes fully more with hydrogen, separates just difficult more with oil at reactor head gas.This can only bring up to the linear velocity of liquid in the reactor about 3cm/s usually with regard to having limited circulating pump.If want further to improve the flow velocity of liquid by the rotating speed that improves pump, will be owing to the increase of gas content from the material of top suction, generation vapour lock and pump can't be run well.Even under such liquid speed, the material in the reactor also exists density contrast, promptly Jiao who generates in the course of reaction is more at reactor bottom, and is less at the top.And material is discharged from reactor head, after Chen Ji Jiao stagnates a period of time in reactor like this, will form bulk and stops up reactor.Another problem be can't guarantee circulating pump can be under high temperature, high pressure long-term operation continuously, in case circulating pump breaks down, Jiao of generation will deposit to the bottom of reactor rapidly.

Address the above problem and can start with from two approach: the one, adopt material to discharge, like this no matter whether Jiao who generates to the bottom sedimentation, can both discharge from reactor bottom; The 2nd, change the material endless form.Owing to exist the localized heat release phenomenon in the course of reaction, and should not eliminate with the method for annotating cold hydrogen, the material circulation must keep, traditional circulation flow reactor is exactly to consider from changing the material endless form, relies on the effect of circulation tube, and without circulating pump, improve the linear velocity of liquid in reactor, and then improve the jacking capacity of liquid, Jiao is given rise to the reactor head outlet solid particle.But traditional circulation flow reactor has only an interior circulation tube usually, even have a plurality ofly, the length of circulation tube is constant, internal diameter also is identical.In traditional circulation flow reactor, because velocity of circulation is fast, the liquid flow velocity of reactor top and the bottom is the same, and mixing of materials rapid and that reacted was even after fresh material entered reactor, and material is formed basically identical in the whole reactor.Like this, in the material of discharging from reactor, the material that had both responded has the fresh feed that has just entered reactor again.In the material that in reactor, circulates, the material that also responded and be discharged from for a long time and not, the gas and the Jiao that make reaction generate increase, and this situation causes adverse influence to course of reaction.

The purpose of this utility model is that a kind of novel circulation flow reactor that is different from traditional circulation flow reactor will be provided, eliminate the local heat effect in the reactor, make material keep back-mixing, the temperature homogeneous, the average gas that improves in the reactor contains rate, Jiao reduces the jacking capacity of liquid, so that can discharge by the discharge gate of reactor bottom as soon as possible to the reactor bottom sedimentation to solid particle.

Two circulation tubes about the purpose of this utility model is achieved in that and is equipped with in the housing of reactor, comparatively speaking, last circulation tube is longer, and internal diameter is bigger; Following circulation tube is shorter, and internal diameter is less, is fixed in the reactor with circulation tube about the circulation tube supporting construction handle, and the temperature-measuring heat couple sleeve pipe is housed between circulation drum outer wall and reactor.The hydrogen distributor of an annular is respectively installed in the interior outside at following circulation tube.Compare, the less hydrogen distributor percent opening of internal diameter is higher, and the installation site is lower; The hydrogen distributor percent opening that internal diameter is bigger is lower, and the installation site is higher, and is that two semi-rings connect into a domain by flange.The inner member loading port is arranged at the top of reactor, and the diameter of mouth is not less than the external diameter of circulation tube.By measuring and control the liquid level in the reactor, reacted material is discharged from the discharging opening of reactor bottom.

The utility model adopts up big and down small circulation barrel structure, and it can strengthen the time of contact of gas and liquid; Allow the material (gas, liquid and solid) in the reactor be in the back-mixing state, eliminate the hot-spot in the reactor in the course of reaction.Simultaneously,, selectively, promptly discharge reactor, be unlikely the solid that in reactor, is agglomerated into bulk solid particle that produces in the course of reaction and the solid particle of in course of reaction, growing up.Because adopted two sections circulation, and the flow rate of liquid difference of reactor top and the bottom, the flow rate of liquid of lower part is slower.Fresh material enters epimere rapidly after entering reactor, and even with the mixing of materials of having reacted, and most of material is to carry out circulation at epimere.Fresh material is more in the epimere circulation, and the material that reacted in the hypomere circulation is more.In the material of discharging from reactor, the composition of fresh feed reduces.This situation is gas and burnt minimizing that reaction generates to the result that influences of course of reaction, and conversion ratio improves.

Describe the concrete structure of the present utility model and the course of work in detail below in conjunction with accompanying drawing.

Fig. 1 is the structural representation according to the designed circulation flow reactor of the utility model.

Fig. 2 be according to the designed reactor of the utility model contain in the course of the work catalyst and burnt particle liquid material flow to schematic diagram.

Fig. 3 be according to the designed reactor of the utility model in the course of the work hydrogen flow to schematic diagram.

Two circulation tubes 6 and 7 are housed in the housing 3 of reactor up and down, and comparatively speaking, last circulation tube 6 is longer, and internal diameter is bigger; Following circulation tube 7 is shorter, and internal diameter is less, with circulation tube support member 4 circulation tube up and down is fixed in the reactor, and temperature-measuring heat couple sleeve pipe 5 is housed between circulation drum outer wall and reactor.The hydrogen distributor 9 and 8 of an annular is respectively installed in the interior outside at following circulation tube.Compare, less hydrogen distributor 9 percent openings of internal diameter are higher, and the installation site is lower; Hydrogen distributor 8 percent openings that internal diameter is bigger are lower, and the installation site is higher, and are that two semi-rings connect into a domain.The inner member loading port is arranged at the top of reactor, and the diameter of mouth is not less than the external diameter of circulation tube.The top of reactor is loam cake 2 and gas vent 1.By measuring and control the liquid level in the reactor, reacted material is discharged from the discharging opening 13 of reactor bottom.

Raw material (containing high degree of dispersion catalyst and a small amount of vulcanizing agent) and hydrogen partial through heating, enter in the following circulation tube 7 in the reactor by heavy oil feed mouth 12 and 10, enter in the circulation tube 6 then rapidly, and then flow repeatedly in the inside and outside formed circulation of last circulation tube, and hydrocracking reaction takes place.Solid particle in the circulation is under the interception of following circulation tube, and difficulty turns back in the inside and outside circulation of circulation tube.The reacted material of small part enters down the outside of circulation tube.

Hydrogen through heating passes through hydrogen feed mouth 14, enter into two inside and outside hydrogen distributors 9 of reactor inner lower ring stream tube and 8 through hydrogen inlet inner connection tube 11, most of hydrogen enters down in the circulation tube 7 by the hydrogen distributor 9 in the following circulation tube, enter then in the circulation tube 6, after arriving the top, part is carried to the outside of circulation tube by flowing liquid.Fraction hydrogen passes through the outer hydrogen distributor 8 of circulation tube down, be distributed in the outer liquid of circulation tube, to alleviate the contradiction of the poor hydrogen of this partially liq, simultaneously, this hydrogen partial has the effect that reduces the outer flow rate of liquid of circulation tube, can reduce the lifting force of liquid, the sedimentation of accelerating solid particle to solid particle.In being partly dissolved in feedstock oil and the participation reaction, all the other hydrogen are discharged reactor from the gas vent 1 on reactor top.

The outside that the solid particle of circulation tube interception and the reacted material of small part enter down the circulation tube under the quilt, under the effect of the hydrogen that the hydrogen distributor outside following circulation tube distributes, continuation is reacted and is also reduced flow velocity, from the discharging opening discharge of reactor bottom.Wherein have part to be carried and enter down in the circulation tube, the concentration of the solid particle that contains in this part is lower than the granule density from the material that discharging opening 13 is discharged.

Reactor and other the reactor difference designed according to the utility model are:

(1) compares with traditional up-flow reactor, the related reactor of the utility model is in full back-mixing state at the maintenance material, eliminates aspect the local heat effect in the reactor, not the mode that adopts circulating pump, but in reactor, add the circulation tube, adopt the method for circulation.

(2) for the liquid that the reduces circulation jacking capacity to solid particle, big solid particle can be discharged from outside the reactor rapidly, form bulk in the reactor and be unlikely to be trapped in for a long time, the slit of circulation tube and reactor bottom is bigger.

(3) traditional circulation flow reactor has only an interior circulation tube usually, even have a plurality ofly, the length of its circulation tube is constant, internal diameter also is identical.Two circulation tubes are up and down arranged in the reactor shell provided by the utility model, and last circulation tube is longer, and internal diameter is bigger; Following circulation tube is shorter, and internal diameter is less.Last circulation tube internal diameter and highly bigger can guarantee that average gas holdup is higher.Following circulation tube internal diameter and highly less can reduce the liquid flow velocity of reactor bottom, makes the rapid sedimentation of solid particle.

(4) compare with traditional circulation flow reactor, use the purpose difference of circulation tube.What traditional circulation flow reactor was pursued is higher circulation liquid velocity, and this also is its outstanding feature.Rely on higher circulation liquid velocity, traditional circulation flow reactor can make material keep back-mixing, temperature homogeneous.Simultaneously, higher circulation liquid velocity can carry out reactor with Jiao of catalyst granules and reaction generation, but still easily deposition is burnt in the bottom of reactor in actual applications, deposits to a certain degree that the back influence velocity of circulation, even stops up the space outside the circulation tube.Because the circulation liquid velocity is higher in the reactor, gas time of staying in reactor is little, gas to contain rate just less, the utilization rate of gas is just lower.In addition, traditional circulation flow reactor needs higher gas flow rate.

It is in order to eliminate the local heat effect of reactor, to make material keep back-mixing, temperature homogeneous that reactor provided by the utility model uses the circulation tube.Will reduce liquid flow velocity as far as possible during reactor work, accelerator activator particle and burnt to the reactor bottom sedimentation is discharged by the discharge gate of reactor bottom.Because the circulation liquid velocity is less in the reactor, gas time of staying in reactor is long, gas to contain rate just higher, the utilization rate of gas is just higher.In addition, this circulation flow reactor can not use high gas flow rate.

(5) under the same reaction conditions, the conversion ratio height of raw material in circulation flow reactor provided by the utility model.Fresh feed is carried in the circulation tube after entering from the end opening that descends the circulation tube, and major part is the inside and outside formation circulation at last circulation tube, and in the material that reactor bottom is discharged, the ratio of the fresh material of complete reaction reduces, so conversion ratio improves.

(6) difference of hydrogen distribution.Except small part hydrogen injects in the stokehold, improve outside the speed of feedstock oil in boiler tube, most of hydrogen is that the hydrogen distributor by two annulars enters reactor.That is, the mode that adopts hydrogen and feedstock oil to enter reactor respectively, rather than the mixed feeding of hydrogen G﹠O.Can reduce the possibility of coking on the distributor like this.

(7) use in traditional up-flow reactor of circulating pump and the traditional circulation flow reactor apparent flow rate of liquid as 3cm/s and 20cm/s about.The reactor that the utility model is related does not require the apparent velocity of liquid reactor, as long as guarantee the reactor temperature homogeneous, can select lower flow velocity for use.

Claims (1)

1. a circulation flow reactor that is used for heavy oil floating bed hydrocracking is characterized in that, up big and down small two circulation tubes (6,7) are housed in reactor, and last circulation tube (6) is longer than following circulation tube (7); At following circulation tube (7) inner bottom part the annular hydrogen distributor (9) that percent opening is higher is installed, the annular hydrogen distributor (8) that percent opening is lower is installed in the outside at following circulation tube (7), hydrogen distributor (8) installation site in the outside is than inner hydrogen distributor (9) height, more close last circulation tube (6).