CN102875294B

CN102875294B - Start-up method of reaction-regeneration device for preparing low-carbon olefins from methanol

Info

Publication number: CN102875294B
Application number: CN201110193423.6A
Authority: CN
Inventors: 齐国祯; 王洪涛; 王华文
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2011-07-12
Filing date: 2011-07-12
Publication date: 2015-01-07
Anticipated expiration: 2031-07-12
Also published as: CN102875294A

Abstract

The invention provides a start-up method of a reaction-regeneration device for preparing low-carbon olefins from methanol, mainly solving the problems of long start-up period, severe degree of catalyst damage, and easy blockage of regeneration inclined pipe in the prior art. The method disclosed herein comprises the following steps: (a) letting heated air enter into the reaction-regeneration device to heat a reactor and a regenerator; (b) transferring a catalyst into the regenerator, and spraying burning oil into the regenerator to keep the temperature of the regenerator; (c) introducing steam heated by an auxiliary oven into the reactor, and introducing back-flushing gas into the reactor through a pipeline 10 in front of a slide valve 27, and transferring the catalyst in the regenerator into the reactor; (d) establishing a catalyst circulation between the reactor and the regenerator; (e) introducing raw materials into the reactor to generate a product and form carbon deposit on the catalyst; (f) stopping using the auxiliary oven, and stopping spraying the burning oil into the regenerator; and (g) stopping an auxiliary combustion chamber. The method disclosed herein well solves the problems and can be used in the industrial production of low-carbon olefins.

Description

The starting method of reaction for preparing light olefins from methanol-regenerating unit

Technical field

The present invention relates to a kind of starting method of reaction for preparing light olefins from methanol-regenerating unit.

Technical background

Low-carbon alkene, i.e. ethene and propylene, be two kinds of important basic chemical industry raw materials, its demand is in continuous increase.Usually, ethene, propylene are produced by petroleum path, but due to the limited supply of petroleum resources and higher price, produce ethene by petroleum resources, the cost of propylene constantly increases.In recent years, people start to greatly develop the technology that alternative materials transforms ethene processed, propylene.Wherein, the important alternative materials for light olefin production of one class is oxygenatedchemicals, such as alcohols (methyl alcohol, ethanol), ethers (dme, methyl ethyl ether), ester class (methylcarbonate, methyl-formiate) etc., these oxygenatedchemicalss can be transformed by coal, Sweet natural gas, biomass equal energy source.Some oxygenatedchemicals can reach fairly large production, and as methyl alcohol, can be obtained by coal or Sweet natural gas, technique is very ripe, can realize the industrial scale of up to a million tonnes.Due to the popularity in oxygenatedchemicals source, add the economy transforming and generate light olefin technique, so by the technique of oxygen-containing compound conversion to produce olefine (OTO), be particularly subject to increasing attention by the technique of preparing olefin by conversion of methanol (MTO).

Be applied to preparing olefin by conversion of methanol technique to silicoaluminophosphamolecular molecular sieve catalyst in US4499327 patent to study in detail, think that SAPO-34 is the first-selected catalyzer of MTO technique.SAPO-34 catalyzer has very high light olefin selectivity, and activity is also higher, methanol conversion can be made to be less than the degree of 10 seconds in reaction times of light olefin, more even reach in the reaction time range of riser tube.

Technology and reactor that a kind of oxygenate conversion is low-carbon alkene is disclosed in US6166282, adopt fast fluidized bed reactor, gas phase is after the lower Mi Xiangfanyingqu of gas speed has reacted, after rising to the fast subregion that internal diameter diminishes rapidly, special gas-solid separation equipment initial gross separation is adopted to go out most entrained catalyst.Due to reaction after product gas and catalyzer sharp separation, effectively prevent the generation of secondary reaction.Through analog calculation, compared with traditional bubbling fluidization bed bioreactor, needed for this fast fluidized bed reactor internal diameter and catalyzer, reserve all greatly reduces.

The multiple riser reaction unit disclosed in CN1723262 with central catalyst return is low-carbon alkene technique for oxygenate conversion, this covering device comprises multiple riser reactor, gas solid separation district, multiple offset components etc., each riser reactor has the port of injecting catalyst separately, be pooled to the disengaging zone of setting, catalyzer and gas product are separated.

Reaction for preparing light olefins from methanol-regeneration alkene and traditional catalytic cracking reaction-regeneration system rapidly are essentially different, and also comparatively catalytic cracking driving is large for driving difficulty.The invention provides a kind of starting method of new reaction for preparing light olefins from methanol-regenerating unit.

Summary of the invention

The invention provides a kind of starting method of new reaction for preparing light olefins from methanol-regenerating unit, the problem that cycle length of mainly driving in solution prior art, heavier, the to be generated inclined tube of catalyst impairment degree easily block up.The method is used for, in the production of low-carbon alkene, having the advantage that driving cycle short, catalyst impairment mild degree, inclined tube to be generated can not block.

The technical solution used in the present invention is as follows: a kind of starting method of reaction for preparing light olefins from methanol-regenerating unit, mainly comprise the following steps: comprise the following steps: (a) adopt auxiliary chamber add warm air laggard enter reaction-regenerative device, by close for revivifier phase section heating temperatures to 400 ~ 600 DEG C, temperature of reactor is heated to 150 ~ 350 DEG C; B catalyzer is proceeded to revivifier by () from catalyzer storage tank, and spray into combustion oil maintenance regenerator temperature; Pass into through the heated water vapour of auxiliary oven in (c) reactor, and purge gas is passed into through pipeline 10 before guiding valve 27, catalyzer in revivifier is proceeded to reactor, ensures that this section of inclined tube inner catalyst density before guiding valve 27 leaves between guiding valve 27 to reactor is less than double centner/rice ³; D () opens guiding valve 27, reduce or cut off the purge gas of pipeline 10, ensures that catalyzer enters revivifier from reactor through inclined tube to be generated, sets up the catalyst recirculation between reactor and revivifier; E reactor reaction zone heating temperatures to after being not less than 350 DEG C, is passed into the raw material comprising methyl alcohol by () in reactor, generate the product that comprises low-carbon alkene and form carbon deposit on a catalyst; F () to be stopped using auxiliary oven, is stopped spraying into combustion oil to revivifier; G () is stopped using auxiliary chamber.

In technique scheme, the combustion medium of described aid burning indoor is selected from diesel oil, fuel gas; Described catalyzer comprises silicoaluminophosphamolecular molecular sieve; Described combustion oil is diesel oil; After catalyzer coke content in reactor is greater than 1% weight, stop spraying into combustion oil to revivifier; Catalyzer in revivifier is proceeded in the process of reactor, continues in revivifier, to proceed to catalyzer from catalyzer storage tank; Described purge gas is at least one in water vapour, nitrogen, fuel gas; Water vapour is heated to 200 ~ 400 DEG C by described auxiliary oven.

Fuel gas of the present invention is mainly containing components such as methane, hydrogen, ethene, propylene.

The starting method of reaction-regeneration system described in drawings and Examples of the present invention, can carry out driving operation according to situations such as actual reaction-regeneration system size, formations according to required operational condition, be not limited to the concrete numerical value described in the embodiment of the present invention.

Because the coking yield of reaction for preparing light olefins from methanol is lower, and methanol molecules amount is less, therefore its reaction-regeneration system has the feature of " large reactor, little revivifier ", be essentially different with the feature of traditional catalytic cracking " little reactor, large revivifier ", this also makes the driving of reaction for preparing light olefins from methanol-regeneration system rapidly different from traditional circulating fluidized bed starting method, and difficulty is larger.The present invention adds to revivifier catalyzer limit to turn method from catalyzer to reactor by adopting limit, shortens the driving cycle, reduces the infringement of catalyzer in startup procedure.The heat of revivifier is by spraying into combustion oil and thermal regeneration air ensures, after system enters methanol feedstock, catalyzer can accumulate a certain amount of carbon deposit gradually, when carbon deposit run up to a certain amount of after, the heat of revivifier just can be maintained by the combustion heat release of carbon deposit, at this moment can remove combustion oil and auxiliary chamber, make reaction-regeneration system smooth running under the thermal equilibrium of self.In addition, owing to proceeding to before catalyzer from revivifier to reactor, what pass in reactor is water vapour, adopts auxiliary oven heating water steam in the present invention, with the blocking of " and mud " or some dead angle of avoiding catalyzer.Simultaneously, owing to proceeding to the initial stage of catalyzer from revivifier to reactor, inclined tube guiding valve to be generated is in closing condition, so the catalyzer before inclined tube guiding valve to be generated is in approximate first valve state, temperature is also lower, very easily there is blockage problem, the method passing into purge gas before inclined tube guiding valve to be generated is adopted in the present invention, reduce the density of catalyst before inclined tube guiding valve to be generated, preferably pass into the purge gas of q.s, with ensure inclined tube guiding valve to be generated open before a large amount of catalyzer do not enter inclined tube to be generated, inclined tube to be generated like this would not blockage phenomenon.

Adopt technical scheme of the present invention: the combustion medium of described aid burning indoor is selected from diesel oil, fuel gas; Described catalyzer comprises silicoaluminophosphamolecular molecular sieve; Described combustion oil is diesel oil; After catalyzer coke content in reactor is greater than 1% weight, stop spraying into combustion oil to revivifier; Catalyzer in revivifier is proceeded in the process of reactor, continues in revivifier, to proceed to catalyzer from catalyzer storage tank; Described purge gas is at least one in water vapour, nitrogen, fuel gas; Water vapour is heated to 200 ~ 400 DEG C by described auxiliary oven, and the cycle of driving, in the operational process of continuous 62 days, yield of light olefins on average reached 81.8% weight, achieves good technique effect substantially between 2 ~ 4 hours.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of scheme of the present invention.

In Fig. 1,1 is reactor feedstocks charging; 2 is reactor reaction zone; 3 is gas-solid sharp separation district; 4 is stripping zone; 5 is reactor outer circulation inclined tube; 6 is feed distribution plate; 7 is the close phase section of revivifier; 8 is reactor gas-solid cyclone separator; 9 is reactor disengaging zone; 10 enter pipeline for purge gas; 11 is product gas outlet pipeline; 12 is revivifier dilute phase section; 13 is regenerating medium source line; 14 is inclined tube to be generated; 15 is external catalyst cooler for regenerator; 16 is revivifier gas-solid cyclone separator; 17 is regenerated flue gas outlet line; 18 is reactor external warmer; 19 is regenerator sloped tube; 20 enter reactor line for steam; 21 is revivifier; 22 is reactor; 23 is combustion oil source line; 24 is the large-scale agent line that adds of regenerator bottoms; 25 is auxiliary oven; 26 is regenerator sloped tube guiding valve; 27 is inclined tube guiding valve to be generated.

The logistics comprising methanol feedstock enters in the reaction zone 2 of reactor 22 through feeding line 1, contact with molecular sieve catalyst, reaction generates the product containing low-carbon alkene, carry reclaimable catalyst and enter reactor disengaging zone 9 through gas-solid sharp separation district 3, wherein, most of catalyzer that gas-solid sharp separation equipment 3 is separated enters stripping zone 4, and gaseous products and part are not separated through entering cyclonic separator 8 separation again by the catalyzer of gas-solid sharp separation device separates, catalyzer turns back to stripping zone 4 through the dipleg of cyclonic separator 8, gaseous products enters follow-up centrifugal station through outlet line 11.After stripping, be divided into two portions by gas-solid sharp separation district 3 and the isolated reclaimable catalyst of cyclonic separator 8, a part turns back to the bottom of reaction zone 2 by external catalyst circulation inclined tube 5; A part enters coke-burning regeneration in the close phase section 7 of revivifier 21 through inclined tube 14 to be generated in addition, the flue gas that coke burning generates enters follow-up energy-recuperation system by exhanst gas outlet pipeline 17 after cyclonic separator 16, and the catalyzer regenerated returns to reaction zone 2 by regenerator sloped tube 19.During driving, catalyzer adds in reaction-regeneration system by the large-scale agent line 24 that adds of regenerator bottoms, and combustion oil enters in the close phase section 7 of revivifier from pipeline 23; Before raw material incision reactor, adopt the middle pressure steam fluidized catalyst cutting reactor from pipeline 20.

Below by embodiment, the invention will be further elaborated, but be not limited only to the present embodiment.

Embodiment

[embodiment 1]

Reaction for preparing light olefins from methanol-regeneration system rapidly as shown in Figure 1, reactor is fast bed, revivifier is dense bed, catalyzer is SAPO-34 molecular sieve, methanol feeding amount is 4.2 tons/hour, reactor height overall 28.7 meters, revivifier height overall 24.3 meters, aid burning indoor pass into fuel gas igniting for being heated by regeneration air, enter revivifier after regeneration air is heated, revivifier is heated to about 450 DEG C, improve regeneration pressure, make regeneration air can enter reactor by regenerator sloped tube and inclined tube to be generated, and reactor is heated to about 230 DEG C.Catalyzer is proceeded to revivifier by the large-scale agent line that adds from catalyzer storage tank, when regenerator bed material level arrives more than combustion oil nozzle location 1 meter, and after revivifier close phase section temperature is greater than 370 DEG C, spraying into combustion oil to the close phase section of revivifier, combustion oil adopts hydrogenated diesel oil.Diesel oil sprays into and fast close for revivifier phase section temperature is risen to more than 550 DEG C afterwards, accelerates the speed proceeding to catalyzer in revivifier simultaneously; When revivifier material level reaches 62%, beds did not have cyclone dip-leg, when revivifier close phase section temperature is 530 DEG C, possessed and turned agent condition to reactor.Before turning agent, middle pressure steam is passed in reactor, and adopt auxiliary oven to heat middle pressure steam, ensure that reactor each point temperature is more than 230 DEG C, simultaneously, pass into purge gas before inclined tube guiding valve to be generated, purge gas is through the heated water vapour of auxiliary oven, ensures that the density of the catalyzer before inclined tube guiding valve to be generated is 40 ~ 80 kg/m 3.Open regenerator sloped tube guiding valve, catalyzer is proceeded to reactor, the catalyzer proceeding to reactor enters disengaging zone and stripping zone through fast bed reaction zone, after the material level of stripping zone has display and temperature obviously rises, open inclined tube guiding valve to be generated, cut off purge gas, make catalyzer can enter revivifier from inclined tube to be generated, set up the catalyst recirculation between reactor and revivifier gradually; Proceed to the process of reactor at catalyzer from revivifier, continue to proceed to catalyzer from catalyzer storage tank to revivifier, until the catalyst inventory in reactor and revivifier arrives design load; After circulation set up by two devices, the high temperature catalyst of being come by regenerator sloped tube from revivifier by reactor reaction zone heating temperatures to about 380 DEG C time, pass into methanol feedstock in reactor, reduce quantity of steam according to certain ratio simultaneously, and cut off auxiliary oven.The catalyst exposure of raw material and reaction zone, generation comprises the product of low-carbon alkene and forms carbon deposit on a catalyst; When reclaimable catalyst carbon deposit reaches 1.36% weight, stop spraying into combustion oil to revivifier; When reclaimable catalyst carbon deposit reaches more than 3.7% weight, auxiliary chamber of stopping using.

Whole startup procedure lasts about 2.7 hours, and in the operational process of continuous 62 days, yield of light olefins on average reaches 81.8% weight.

Obviously, adopt method of the present invention, can reach and shorten the driving cycle, reduce catalyst impairment degree, the object preventing inclined tube to be generated from blocking, has larger technical superiority, can be used in the industrial production of low-carbon alkene.

Claims

1. a starting method for reaction for preparing light olefins from methanol-regenerating unit, comprises the following steps:

(a) adopt auxiliary chamber add warm air laggard enter reaction-regenerative device, by close for revivifier phase section heating temperatures to 400 ~ 600 DEG C, temperature of reactor is heated to 150 ~ 350 DEG C;

B catalyzer is proceeded to revivifier by () from catalyzer storage tank, and spray into combustion oil maintenance regenerator temperature;

Pass into through the heated water vapour of auxiliary oven in (c) reactor, and pass into purge gas through pipeline (10) guiding valve (27) is front, catalyzer in revivifier is proceeded to reactor, ensures that this section of inclined tube inner catalyst density before guiding valve (27) leaves between guiding valve (27) to reactor is less than double centner/rice ³;

D () opens guiding valve (27), reduce or cut off the purge gas of pipeline (10), ensures that catalyzer enters revivifier from reactor through inclined tube to be generated, sets up the catalyst recirculation between reactor and revivifier;

E reactor reaction zone heating temperatures to after being not less than 350 DEG C, is passed into the raw material comprising methyl alcohol by () in reactor, generate the product that comprises low-carbon alkene and form carbon deposit on a catalyst;

F () to be stopped using auxiliary oven, is stopped spraying into combustion oil to revivifier;

G () is stopped using auxiliary chamber;

Wherein, water vapour is heated to 200 ~ 400 DEG C by auxiliary oven;

Described purge gas is at least one in water vapour, nitrogen, fuel gas.

2. the starting method of reaction for preparing light olefins from methanol-regenerating unit according to claim 1, is characterized in that the combustion medium of described aid burning indoor is selected from diesel oil, fuel gas.

3. the starting method of reaction for preparing light olefins from methanol-regenerating unit according to claim 1, is characterized in that described catalyzer comprises silicoaluminophosphamolecular molecular sieve.

4. the starting method of reaction for preparing light olefins from methanol-regenerating unit according to claim 1, is characterized in that described combustion oil is diesel oil.

5. the starting method of reaction for preparing light olefins from methanol-regenerating unit according to claim 1, is characterized in that after catalyzer coke content in reactor is greater than 1% weight, stops spraying into combustion oil to revivifier.

6. the starting method of reaction for preparing light olefins from methanol-regenerating unit according to claim 1, is characterized in that the catalyzer in revivifier to proceed in the process of reactor, continues in revivifier, to proceed to catalyzer from catalyzer storage tank.