Application of an iron-based catalyst in upgrading inferior / heavy oil in a slurry bed

Abstract

The present invention discloses an application of an iron-based catalyst in the hydro-upgrading of inferior / heavy oil in a slurry bed. In the present invention, a precipitant, an iron salt and / or an additive are oppositely sprayed into a suspension forming tower, and raw materials collide and mix to form catalyst precursor droplets, and then form ultrafine and highly dispersed powders, which serve as the iron-based catalyst. The inferior / heavy oil includes original geological reservoir heavy oil, heavy oil by-products in the process of petroleum refining and processing, heavy oil and asphalt refined from oil sands and oil shales, and tar by-products in the hot processing of heavy hydrocarbon raw materials. By adjusting the temperature gradient and atmosphere in the tower, the present invention can effectively control the catalyst phase. During the hydro-upgrading reaction process, when the catalyst contacts the reactants (heavy / inferior oil), it is in the best active state and has better hydro-upgrading ability.

Description

Technical Field

[0001] The present invention relates to the application of an iron-based catalyst in the hydro-upgrading of inferior / heavy oil in a slurry bed, belonging to the field of energy chemical engineering. Background Art

[0002] At present, the world's petroleum shows a trend of heavy and inferior quality. However, the demand for heavy fuel oil in today's society is decreasing year by year, while the market demand for light chemical oil and clean vehicle fuel oil is increasing day by day. An effective way is to efficiently utilize the existing petroleum resources to ensure the supply of energy and chemical raw materials. Therefore, in recent years, the research on the efficient conversion of inferior / heavy oil into light oil has received much attention.

[0003] Inferior / heavy oil includes original geological reserve heavy oil (such as: viscous oil, high-viscosity crude oil, natural asphalt), heavy oil by-products in the process of petroleum refining and processing (such as: atmospheric residue, vacuum residue, coker gas oil), and heavy oil and asphalt extracted from oil sands and oil shales. Its processing often adopts decarbonization process or hydrogenation process. The decarbonization process includes solvent deasphalting and thermal processing, etc. This type of method has strong raw material adaptability. However, the solvent consumption is large and the energy consumption is high. The hydrogenation process is conducive to converting inferior / heavy oil into high-value-added products and reducing coke formation conversion. Currently, the research mainly focuses on the hydrogenation process.

[0004] The reactors for the hydrogenation process include fixed beds and slurry beds. Fixed-bed reactors are only suitable for inferior / heavy oil with low heavy-degree. If the heavy-degree is too high, the reactor is prone to blockage and the catalyst is prone to deactivation, resulting in a short equipment operation cycle and high catalyst replacement cost in actual production. Slurry-bed reactors have the advantages of a wide range of raw material applicability, good mass and heat transfer effects during the reaction, and flexible product distribution, and are more suitable for converting various types of inferior / heavy oil and are currently widely studied.

[0005] The catalytic hydrogenation ability of the catalyst used in the hydrogenation process is the key to the inferior / heavy oil hydrogenation process technology. The catalysts for slurry-bed reactors can currently be divided into two major categories: homogeneous and heterogeneous. Homogeneous catalysts are mainly oil-soluble molybdenum-based catalysts with good performance. However, the preparation of this type of catalyst requires expensive organic ligands, resulting in a relatively high cost. Heterogeneous catalysts are solid powder types, specifically divided into noble metal nickel molybdenum and inexpensive iron-based catalysts. Nickel molybdenum-based catalysts have better performance than iron-based catalysts, but they are expensive and difficult to recycle and regenerate. Iron-based catalysts have low cost and can be used once without recycling and regeneration.

[0006] Iron-based catalysts mainly come from two sources: one is nature, and the other is chemical synthesis. Natural iron-containing ores (including pyrite, limonite, and pyrrhotite) are not rare. However, how to effectively and low-consumption grind these iron-containing ores into ultrafine powders to obtain ideal catalytic activity is a major problem. In addition, the chemical composition and structure of natural iron-containing minerals are mostly not the best catalytic hydrogenation active phases.

[0007] By means of chemical synthesis, micron- or even nano-scale specific-phase iron-based products can be obtained. When used for the hydro-upgrading of inferior / heavy oil, high dispersion is easily achieved, enabling the catalyst activity and utilization rate to be in the best state. To further optimize the catalyst preparation method, improve the metal dispersion, and reduce the catalyst preparation cost. The present invention discloses a preparation method and application of a highly dispersed iron-based catalyst for the slurry bed hydro-upgrading of inferior / heavy oil. The precipitant, iron salt, and / or additive are oppositely sprayed into a suspension forming tower, and the raw materials collide and mix to form catalyst precursor droplets. The droplets suspend and descend, contacting the upward hot gas flow countercurrently, and successively undergo drying, calcination, and / or activation processes, which are beneficial to the formation of ultra-fine and highly dispersed phases and the catalyst powder with the required composition and structure. The particle size distribution of the catalyst powder is adjusted by changing the number and diameter of the nozzles; the phase of the catalyst powder is controlled by adjusting the temperature gradient and atmosphere inside the tower. It has the characteristics of simple preparation process, high raw material utilization rate, and low water consumption, can effectively reduce the production cost of the catalyst, and the highly dispersed phase is beneficial to improving the hydro-upgrading efficiency of inferior / heavy oil. Summary of the Invention

[0008] The object of the present invention is to provide the application of an iron-based catalyst in the slurry bed hydro-upgrading of inferior / heavy oil, which can improve the hydro-upgrading efficiency of inferior / heavy oil.

[0009] The inferior / heavy oil involved in the present invention includes original geological reserve heavy oil (such as: heavy oil, high-viscosity crude oil, natural asphalt), heavy oil by-products in the process of petroleum refining and processing (such as: atmospheric residue, vacuum residue, coker gas oil), heavy oil and asphalt refined from oil sands and oil shales, and by-product tar in the thermal processing process of heavy hydrocarbon raw materials (such as: dry distillation, liquefaction, gasification, coking).

[0010] The iron-based catalyst involved in the present invention is prepared according to the method including the following steps:

[0011] S1. Prepare a solution of iron salt and a solution of precipitant, and mix them with an additive respectively to obtain mixed slurry 1 and mixed slurry 2;

[0012] S2. After preheating, the working gas is introduced into the suspension forming tower to form an upward gas flow;

[0013] S3. The mixed slurry 1 and the solution of the precipitant, and the mixed slurry 2 and the solution of the iron salt are respectively formed into pressurized reaction raw material 1 and pressurized reaction raw material 2 through a pumping device;

[0014] S4. Feed the pressurized reaction raw material 1 and the pressurized reaction raw material 2 into the suspension forming tower in the form of droplets, oppositely spray them into the upper space of the suspension forming tower, and let the pressurized reaction raw material 1 and the pressurized reaction raw material 2 collide, mix and react to generate catalyst precursor droplets, obtaining the downward flowing material in the suspension tower, which is in cross-flow contact with the upward flowing gas, and undergoes drying, calcination and / or activation processes to form catalyst powder as the iron-based catalyst.

[0015] Among them, in step S1, the iron salt is at least one of aqueous solutions of ferric sulfate, ferric chloride, ferric nitrate, ferrous sulfate, ferrous chloride, ferric acetate or ferrous acetate;

[0016] The precipitant is at least one of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate, ammonium bicarbonate, sodium sulfide, potassium sulfide, calcium hydroxide and barium hydroxide;

[0017] Water is used to prepare the solution of the iron salt and the solution of the precipitant;

[0018] The concentration of the iron salt solution is 10-35%, and the concentration of the precipitant solution is 10-35%.

[0019] Among them, in step S1, the additive is at least one of pulverized coal, coal char, silica gel, pumice, diatomite, montmorillonite, kaolin, clay, silica sol, aluminum sol, fly ash, coal cinder, activated carbon, carbon nanotubes, zeolite, molecular sieve, natural ore, metal-organic framework, alumina and oxides and salts of the following metals;

[0020] Titanium, zirconium, cerium, zinc, manganese, nickel, molybdenum and tungsten.

[0021] Among them, in step S2, the working gas is at least one of air, nitrogen, hydrogen, hydrogen sulfide, carbon monoxide and flue gas;

[0022] The working gas is introduced from the lower part of the suspension forming tower after being preheated;

[0023] The working gas is preheated to 300-600 °C.

[0024] Among them, in step S3, the mass ratio of the pressurized reaction raw material 1 to the pressurized reaction raw material 2 is 0.5-3:1;

[0025] The atomizing device is a pressure atomizing device, a centrifugal atomizing device, a pneumatic atomizing device or an ultrasonic atomizing device;

[0026] At least two of the atomizing devices are arranged oppositely so that the sprayed droplets converge in the same area;

[0027] Control the diameter of the droplets to be less than 1.2 mm.

[0028] Wherein, in step S3, the method further includes the following treatment steps for the dust-containing tail gas discharged from the gas outlet of the suspension forming tower:

[0029] Remove the fine catalyst powder entrained in the dust-containing tail gas through a tail gas dust removal system, and mix the fine catalyst powder with the catalyst powder as the iron-based catalyst for hydro-upgrading of inferior / heavy oil;

[0030] The tail gas dust removal system can be any device commonly used in the art, such as a single-stage or multi-stage cyclone dust removal, bag dust removal, or electrostatic dust removal, or a combination of one or more of them;

[0031] The dedusted tail gas after removing the fine catalyst powder is recycled or discharged after tail gas purification treatment;

[0032] The following tail gas treatment devices can be used for treatment: a heat exchanger, a condensation recovery device, an absorption tower, or a catalytic combustion device, or a combination of one or more of them.

[0033] Compared with the prior art, in the present invention, a precipitant, an iron salt, and / or an additive are oppositely sprayed into a suspension forming tower, and the raw materials collide and mix to form catalyst precursor droplets, and then form ultrafine and highly dispersed powders, which can be better dispersed in the reactants (heavy / low-quality oil), can provide strong hydrogenation ability, and have a higher oil yield.

[0034] By adjusting the temperature gradient and atmosphere in the tower, the present invention can effectively control the catalyst phase. During the hydro-upgrading reaction process, when the catalyst contacts the reactants (heavy / low-quality oil), it is in the best active state and has better hydro-upgrading ability. Detailed Embodiments

[0035] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods.

[0036] Unless otherwise specified, the materials, reagents, etc. used in the following examples can all be obtained from commercial sources.

[0037] In the following examples, the hydro-upgrading performance of the catalyst was evaluated using raw oils: A (viscous oil), B (vacuum residue), and C (coker gas oil) respectively. The composition and properties of the raw oils are shown in Table 1. The reaction conditions were: pressure 3 - 6 MPa, temperature 400 - 450 °C, residence time 30 - 240 min, elemental S / Fe = 1 / 1, and catalyst addition amount 1% - 3% (mass fraction) Fe daf . The hydro-upgrading conditions and results of the raw oils for the catalysts obtained in the corresponding examples are given in Table 2.

[0038] Comparative Example 1: 182.8 kg of ferrous sulfate heptahydrate was added to 817.2 kg of water to prepare a ferrous sulfate solution with a concentration of 10 wt.%. Then 500 kg of alumina was added to obtain a mixed slurry. 300 kg of water was added to 200 kg of ammonia water with a concentration of 25 wt.% to prepare an ammonia water solution with a concentration of 10 wt.%. The above-mentioned mixed slurry and ammonia water solution were pumped into an acid-base mixing kettle in a concurrent flow manner to obtain a precipitated slurry. The precipitated slurry was washed, filtered, dried, and calcined to obtain catalyst D1.

[0039] Example 1: 182.8 kg of ferrous sulfate heptahydrate was added to 817.2 kg of water to prepare a ferrous sulfate solution with a concentration of 10 wt.%; 300 kg of water was added to 200 kg of ammonia water with a concentration of 25 wt.% to prepare an ammonia water solution with a concentration of 10 wt.

[0040] concentration. 500 kg of alumina was added to a stirring mixer, and then 1000 kg of ferrous sulfate solution was added. The device was started and mixed for 0.5 h to obtain a mixed slurry. The mixed slurry and the ammonia water solution with a concentration of 10 wt.% were fed into a pressure atomizer at the upper part of a suspension forming tower through a pumping device according to the preparation ratio, and sprayed into the upper space of the suspension forming tower through an opposed double nozzle (2.0 mm diameter) to form droplets of about 1 mm, which collided and mixed to form the downward flowing material in the suspension forming tower. The air was heated to 300 °C and fed into the bottom of the suspension forming tower through a porous straight tube gas distributor to form an upward flowing gas in the tower, which countercurrently contacted the downward flowing material in the suspension forming tower, and underwent the processes of synthesis, drying, and calcination. Catalyst product (A1) and dust-containing tail gas were obtained at the bottom of the tower. The dust-containing tail gas was introduced into a secondary cyclone separation system at the top of the suspension forming tower to collect catalyst fines (B1) and dedusted tail gas. The dedusted tail gas was introduced into a condensation recovery device, and the air was recycled after condensing the water vapor. Catalysts A1 and B1 were uniformly mixed to obtain catalyst C1, which was stored in a nitrogen atmosphere.

[0041] Example 2: Add 200 kg of ferric chloride to 800 kg of water to prepare a ferric chloride solution with a concentration of 20 wt.%; add 150 kg of sodium carbonate to 600 kg of water to prepare a sodium carbonate solution with a concentration of 20 wt.%; add 1000 kg of ferric chloride into a rotary kiln, then add 250 kg of kaolin, start the device, and mix for 0.1 h to obtain a mixed slurry; pump the mixed slurry and the 20 wt.% sodium carbonate solution into the centrifugal atomizer at the upper part of the suspension forming tower according to the preparation ratio through a pumping device, and spray them into the upper space of the suspension forming tower through an opposed triple nozzle (1.4 mm in diameter) to form 0.7 mm droplets. The materials collide and mix to form the downward-flowing materials in the suspension forming tower; heat the 20% hydrogen sulfide / nitrogen mixed gas to 450 °C and send it into the bottom of the suspension forming tower through a straight pipe baffle gas distributor to form an upward gas flow in the tower, which contacts the downward-flowing materials in the suspension forming tower countercurrently, undergoes drying, roasting, and activation processes, and obtains a catalyst product (A2) and dust-containing tail gas at the bottom of the tower; introduce the dust-containing tail gas into the bag dust removal separation system at the top of the suspension forming tower to collect catalyst fines (B2) and dedusted tail gas; introduce the dedusted tail gas into an alkali liquor absorption tower, and recycle the purified tail gas. The catalyst A2 and B2 are uniformly mixed to obtain a catalyst C2, which is stored in solvent oil.

[0042] Example 3: Add 350 kg of iron acetate to 650 kg of water to prepare an iron acetate solution with a concentration of 35 wt.%; add 270 kg of sodium hydroxide to 480 kg of water to prepare a sodium hydroxide solution with a concentration of 35 wt.%; start a kneader, and add 750 kg of sodium hydroxide solution and 250 kg of fly ash simultaneously, and mix for 1.5 h to obtain a mixed slurry; pump the mixed slurry and the 35 wt.% iron acetate solution into the ultrasonic atomizer at the upper part of the suspension forming tower according to the preparation ratio through a pumping device, and spray them into the upper space of the suspension forming tower through an opposed quadruple nozzle (1.0 mm in diameter) to form about 0.5 mm droplets. The materials collide and mix to form the downward-flowing materials in the suspension forming tower; send the flue gas at a temperature of 600 °C into the bottom of the suspension forming tower through a tangential horn-shaped gas distributor to form an upward gas flow in the tower, which contacts the downward-flowing materials in the suspension forming tower countercurrently, undergoes drying and roasting processes, and obtains a catalyst product (A3) and dust-containing tail gas at the bottom of the tower; introduce the dust-containing tail gas into the electrostatic precipitation system at the top of the suspension forming tower to collect catalyst fines (B3) and dedusted tail gas; introduce the dedusted tail gas into a heat exchanger tower and an alkali liquor absorption tower in sequence, and discharge it after purification. The catalyst A3 and B3 are uniformly mixed to obtain a catalyst C3, which is sealed with liquid paraffin.

[0043] Example 4: 100 kg of iron nitrate and 100 kg of iron sulfate were added to 600 kg of water to prepare an iron salt solution with a concentration of 25 wt.%; 50 kg of sodium sulfide and 50 kg of sodium hydroxide were added to 400 kg of water to prepare a precipitant solution with a concentration of 20 wt.%; 200 kg of molecular sieve and 100 kg of kaolin were added to a stirring mixer, and then 500 kg of the 20 wt.% precipitant solution was added. The device was started and mixed for 3 h, and then the slurry was added to a kneader and mixed for 1 h; the obtained mixed slurry and the 25 wt.% iron nitrate solution were fed into the pneumatic atomizer at the upper part of the suspension forming tower through a pumping device according to the preparation ratio, and sprayed into the upper space of the suspension forming tower through a counterposed double nozzle (0.5 mm in diameter) to form droplets of about 0.3 mm. The materials collided and mixed to form the downward flowing materials in the suspension forming tower; nitrogen gas at 500 °C was fed into the bottom of the suspension forming tower through a porous straight tube type gas distributor to form an upward flowing gas in the tower, which countercurrently contacted the downward flowing materials in the suspension forming tower, underwent the drying and roasting processes, and a catalyst product (A4) and dust-containing tail gas were obtained at the bottom of the tower; the dust-containing tail gas was successively introduced into the secondary cyclone separation system and the electrostatic precipitator system at the top of the suspension forming tower to collect catalyst fines (B4) and dedusted tail gas; the dedusted tail gas was successively introduced into a heat exchanger and a condensation recovery device, and the nitrogen gas was recycled after the water vapor was recovered. The catalyst A4 and B4 were uniformly mixed to obtain a catalyst C4, which was stored in water.

[0044] Example 5: 100 kg of iron sulfate was added to 400 kg of water to prepare an iron sulfate solution with a concentration of 20 wt.%; 200 kg of ammonium carbonate was added to 800 kg of water to prepare an ammonium carbonate solution with a concentration of 20 wt.%; the device was started, and 200 kg of pulverized coal and 500 kg of the 20 wt.% iron sulfate solution were fed into a pipeline mixer and mixed for 0.1 h to obtain a mixed slurry; the mixed slurry and the 20 wt.% ammonium carbonate solution were fed into the centrifugal atomizer and the pressure atomizer at the upper part of the suspension forming tower through a pumping device respectively, and sprayed into the upper space of the suspension forming tower through a counterposed four-nozzle (1.0 mm in diameter) to form droplets of about 0.7 mm. The materials collided and mixed to form the downward flowing materials in the suspension forming tower; 10% carbon monoxide / hydrogen at 350 °C was fed into the bottom of the suspension forming tower through a straight tube baffle type gas distributor and a porous straight tube type gas distributor to form an upward flowing gas in the tower, which countercurrently contacted the downward flowing materials in the suspension forming tower, underwent the drying and roasting processes, and a catalyst product (A5) and dust-containing tail gas were obtained at the bottom of the tower; the dust-containing tail gas was introduced into the secondary cyclone separation system at the top of the suspension forming tower to collect catalyst fines (B5) and dedusted tail gas; the dedusted tail gas was introduced into an absorption tower and reused after purification. The catalyst A5 and B5 were uniformly mixed to obtain a catalyst C5, which was liquid-sealed in solvent oil.

[0045] Table 1 Properties of Feedstocks A, B and C

[0046]

[0047] Table 2 Feedstock oil hydrogenation upgrading conditions and main results of the catalysts obtained in Examples 1-5

[0048]

[0049]

[0050] As can be seen from the data in Table 2, the present invention uses a highly dispersed iron-based catalyst for hydrogenation and upgrading of heavy / low-quality oil, which can improve the hydrogenation and upgrading efficiency of heavy / low-quality oil, and has a higher yield of distillate oil <520°C and a lower coke formation rate.

Claims

1. Application of an iron-based catalyst in the slurry bed hydro-upgrading of inferior / heavy oil, characterized in that: The preparation method of the iron-based catalyst comprises the following steps: S1. Prepare a solution of an iron salt and a solution of a precipitant, and mix them with an additive respectively to obtain mixed slurry 1 and mixed slurry 2; S2. After preheating, introduce the working gas into the suspension forming tower to form an upward gas flow; S3. Respectively pump the mixed slurry 1 and the solution of the precipitant, and the mixed slurry 2 and the solution of the iron salt through a pumping device to form pressurized reaction raw material 1 and pressurized reaction raw material 2; S4. Feed the pressurized reaction raw material 1 and the pressurized reaction raw material 2 into the suspension forming tower in the form of droplets, oppositely spray them into the upper space of the suspension forming tower, the pressurized reaction raw material 1 and the pressurized reaction raw material 2 collide and mix to react, generating catalyst precursor droplets, obtaining the downward flowing material in the suspension tower, which is in cross-flow contact with the upward gas flow, and undergoes drying, calcination and / or activation processes to form catalyst powder as the iron-based catalyst.

2. The application according to claim 1, characterized in that: The inferior / heavy oil includes original geological reservoir heavy oil, heavy oil by-produced in the process of petroleum refining and processing, heavy oil and asphalt refined from oil sands and oil shales, and tar by-produced in the thermal processing of heavy hydrocarbon raw materials.

3. The application according to claim 1 or 2, characterized in that: In step S1, the iron salt is at least one of ferric sulfate, ferric chloride, ferric nitrate, ferrous sulfate, ferrous chloride, ferric acetate or ferrous acetate; The precipitant is at least one of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate, ammonium bicarbonate, calcium hydroxide and barium hydroxide; Water is used to prepare the solution of the iron salt and the solution of the precipitant; The mass percentage concentration of the solution of the iron salt is 10-35%, and the mass percentage concentration of the solution of the precipitant is 10-35%.

4. The application according to claim 1 or 2, characterized in that: In step S1, the additive is at least one of pulverized coal, coal char, silica gel, pumice, diatomite, montmorillonite, kaolin, clay, silica sol, alumina sol, fly ash, coal cinder, activated carbon, carbon nanotubes, molecular sieve, metal-organic framework, alumina and oxides and salts of the following metals; The metal is titanium, zirconium, cerium, zinc, manganese, nickel, molybdenum and tungsten.

5. The application according to claim 1 or 2, characterized in that: In step S2, the working gas is at least one of air, nitrogen, hydrogen, hydrogen sulfide, carbon monoxide and flue gas; The working gas is introduced from the lower part of the suspension forming tower after preheating; The working gas is preheated to 300-600 °C.

6. The application according to claim 1 or 2, characterized in that: In step S3, the mass ratio of the pressurized reaction raw material 1 to the pressurized reaction raw material 2 is 0.5-3:1; In step S4, the device for forming droplets is an atomizing device, and the atomizing device is a pressure atomizing device, a centrifugal atomizing device, a pneumatic atomizing device or an ultrasonic atomizing device; At least two of the atomizing devices are arranged oppositely so that the sprayed droplets meet in the same area; Control the diameter of the droplets to be less than 1.2 mm.

7. The application according to claim 1 or 2, characterized in that: In step S4, the following treatment steps for the dust-containing tail gas discharged from the gas outlet of the suspension forming tower are further included: The catalyst fines entrained in the dusty tail gas are removed by a tail gas dust removal system, and the catalyst fines are mixed with catalyst powder to be used as the iron-based catalyst for hydro-upgrading of inferior / heavy oil. The dedusted tail gas after removing the catalyst fines is recycled or vented after tail gas purification treatment.

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