CN115125035A - Method for producing synthesis gas from petroleum coke - Google Patents

Abstract

The invention relates to a method for producing synthesis gas from petroleum coke, which comprises the following steps: the petroleum coke particles contact with a gasifying agent under the condition of gasification reaction to carry out gasification reaction, the gasification reaction product flows out from a reactant outlet at the top of the fluidized bed gasification furnace, synthesis gas is obtained after separation, part of fine coke powder is extracted from a fine coke powder outlet of the fluidized bed gasification furnace and collected, and the vanadium content of the obtained fine coke powder is not less than 0.1 weight percent. The invention can gasify the inferior petroleum coke to prepare the synthesis gas, and simultaneously collect the fine coke powder particles rich in metal, thereby being convenient for recovering the nickel-vanadium metal and changing waste into valuable.

Description

A kind of method for producing synthesis gas from petroleum coke

technical field

The invention relates to the field of petroleum coke treatment, in particular to a method for producing synthesis gas from petroleum coke.

Background technique

The trend of heavierization of crude oil is becoming more and more obvious, and the related refining process shows an increasing amount of carbonaceous materials. Delayed coking converts low-quality resid to light oil at a lower cost, but at the same time by-produces about 20% of petroleum coke. Due to the high content of miscellaneous elements in petroleum coke, environmental protection factors must be considered for further utilization. Therefore, in the absence of appropriate treatment methods, petroleum coke, especially low-quality petroleum coke, is strictly restricted from burning petroleum coke in large-scale power plants.

CN110684563A discloses a high-sulfur and inferior petroleum coke gasifier and its gasification method. The method adopts an entrained flow method to gasify the petroleum coke. The petroleum coke fine powder is injected vertically from the petroleum coke powder inlet at the top of the gasifier, and the gasification agent composed of O ₂ /H ₂ O/CO ₂ /N ₂ is imported from the high oxygen concentration gasification agent inlet at the top of the gasifier It is sprayed into the gasifier along the vertical direction, and the reaction temperature is controlled in the range of 1200-1600℃, the pressure is 0.1-8.0MPa, and the gas-solid contact time is 5-20s, so that the petroleum coke and the gasification agent undergo high-temperature gasification reaction to generate rich CO and _H2 gases. The high-temperature gas and slag flow downwards and enter the cooling conversion section through the flared section. Water or steam is sprayed into the gasifier from the atomizing nozzle located on the flared section to cool the reaction temperature to 700-1000℃, and some CO H ₂ is generated through high temperature steam shift reaction, and the residence time of the gas in the cooling shift section is 5-20s.

CN110205165A discloses a combined bed coal gasification system and method, including a raw coal feeding unit, a fly ash circulating feeding unit, a combined bed coal gasification unit, a heat recovery and dust removal unit, and the combined bed coal gasification unit includes a circulating fluidization unit Bed gasifier and entrained bed gasifier, the upper part of the entrained bed gasifier is provided with a radiant waste boiler room, and the upper part of the circulating fluidized bed gasifier is provided with a supplementary heat reaction zone. The supplemental heat reaction zones are connected. The invention realizes the circulating treatment and effective utilization of fly ash through a combined bed system of a circulating fluidized bed and an entrained flow bed.

When the existing entrained bed pulverized coal gasification technology is used to blend petroleum coke, the ash content of petroleum coke is much lower than that of coal, and the conversion rate of petroleum coke is low under conventional entrained bed operating conditions.

The general raw material of the fluidized bed gasifier is coal, and the operation mode is a circulating fluidized bed. Factors such as slagging, particle adhesion, particle circulation, gas-solid separation, etc. that affect the operation of the gasifier need to be considered. The ash content of petroleum coke is very low, and the ash composition is quite different from that of coal ash. When the existing technology of circulating fluidized bed coal gasification is used for petroleum coke gasification, a large amount of water vapor will be consumed because the gas velocity is too large.

Petroleum coke also contains tens to over a thousand ppm of vanadium metal. Vanadium is a relatively rare metal with high utilization value. If high-value vanadium can be recovered, it will have the effect of turning waste into treasure.

SUMMARY OF THE INVENTION

The present invention is to solve the problems of low carbon conversion rate when petroleum coke is used for gasification in the prior art, and the problem that vanadium metal in petroleum coke cannot be recovered and utilized.

The invention provides a method for producing synthesis gas from petroleum coke, which comprises the following steps: entering petroleum coke particles into the fluidized bed gasifier from a petroleum coke feeding port of the fluidized bed gasifier, and gasifying agent from the fluidized bed gasifier The gasification agent feed port at the bottom enters the fluidized bed gasifier, and the petroleum coke particles are contacted with the gasification agent under the gasification reaction conditions to carry out gasification reaction, and the gasification reaction product is obtained from the reactant at the top of the fluidized bed gasifier. It is extracted from the outlet, and after separation, synthesis gas is obtained, and part of the fine coke is extracted and collected from the fine powder coke discharge port of the fluidized bed gasifier. The vanadium content of the obtained fine powder coke is not less than 0.1% by weight. It is arranged on the side wall of the fluidized bed gasifier, above the feed port of the petroleum coke.

In the present invention, "above" refers to the spatial positional relationship in the axial direction, and has nothing to do with the positional relationship between the two in a plan view.

In the present invention, the petroleum coke comes from a delayed coking process, and the particle size of the petroleum coke particles entering the fluidized bed gasifier is 0.1-3 mm. Preferably, the particle size of the petroleum coke particles is 0.1-1.5 mm, more preferably 0.1-1.0 mm.

In an embodiment of the present invention, the gasification reaction conditions are: reaction temperature of 800-1300°C, reaction pressure of 0.1-5.0 MPa, and residence time of petroleum coke particles of 20-60 minutes, preferably 30-50 minutes. In the present invention, different pressure levels can be selected according to the downstream process requirements.

In an embodiment of the present invention, the reaction temperature is 900-1200°C, preferably 1000-1100°C.

In an embodiment of the present invention, a gas distribution plate is arranged above the gasification agent feed port of the fluidized bed gasifier, and a gas outlet is arranged on the gas distribution plate, and the gas velocity at the outlet is 1-5 m/s. The air velocity of the bed is 0.2 to 1.0 m/s.

In an embodiment of the present invention, an appropriate number of caps are distributed on the gas distribution plate to change the gas flow direction, so that the gas flow in the bed is more uniform. After the gasification agent gas is fully mixed, it enters the bottom of the fluidized bed from the cap on the gas distribution plate, and fully contacts and reacts with the petroleum coke particles.

In an embodiment of the present invention, the gasifying agent is a mixed gas I of water vapor and oxygen, and the molar content of water vapor in the mixed gas I is between 50% and 85%; or the gasifying agent is a mixture of water vapor and air Gas II, the molar content of water vapor in the mixed gas II is between 5 and 20%.

In an embodiment of the present invention, the mixed gas I or the mixed gas II contains carbon dioxide, and in the mixed gas I, the carbon dioxide molar content is 10-30%, and the water vapor molar content is 20-65%; Among them, the molar content of carbon dioxide is 10-30%, and the molar content of water vapor is 5-10%.

In an embodiment of the present invention, the feed temperature of the gasification agent is 100-500°C. After the gases of the gasification agent are uniformly mixed by the mixer, the gasification agent enters the fluidized bed gasifier from the gasification agent feed port at the bottom of the fluidized bed gasifier under the condition of 100-500 °C, and the gas is distributed through the gasifier. The plates enter the bottom of the fluidized bed.

In an embodiment of the present invention, the bed height of the fluidized bed in the fluidized bed gasifier is 5-20 m, preferably 6-10 m.

In an embodiment of the present invention, the height-diameter ratio of the fluidized bed gasifier is between 0.4 and 4. When the bed diameter is small, the height-diameter ratio is selected in a larger range; when the bed diameter is larger, the height-diameter ratio is selected in a smaller range.

The solid particles of petroleum coke are fully contacted with the gasification agent. Under the conditions of gasification reaction, the gasification reaction is carried out, and the particle size of petroleum coke becomes smaller and becomes fine powder coke, and the relative metal content on the fine powder coke is increased. In the present invention, part of the fine powder coke is collected through the fine powder coke discharge port.

The remaining part of the fine powder coke and the solid particles smaller than the fine powder coke particle size are carried out by the gas, and are separated and collected by the cyclone separator. The high-temperature gas of the reaction product is further cooled, dedusted, and sent to the downstream process, which can be used as a C ₁ chemical raw material, or as a sulfur-resistant shift hydrogen production raw material gas, or as a raw material gas for synthesizing methane.

In one of the embodiments of the present invention, the petroleum coke feed port is set at 1/3 to 2/3 of the bed height of the fluidized bed; the fine powder coke discharge port is set at 1/3 of the bed height of the fluidized bed. /2 to 5/6.

In one of the embodiments of the present invention, 1-6 petroleum coke feed ports are provided on the side wall of the fluidized bed gasifier.

In one embodiment of the present invention, the particle size of the obtained fine powder coke is 0.02-0.2 mm, and the vanadium content of the obtained fine powder coke is 0.1-2.1% by weight.

The present invention converts various petroleum cokes including high-sulfur petroleum cokes into synthesis gas, which is then used as _C1 chemical raw material gas or raw material gas for hydrogen production, and at the same time, fine powder coke with smaller particles and increased metal content is converted from the stream The fluidized bed gasifier extracts, collects and recovers the nickel and vanadium metals enriched in the fine coke particles, turning waste into treasure.

Description of drawings

FIG. 1 is a schematic diagram of one embodiment of the method for producing synthesis gas from petroleum coke provided by the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited thereby.

FIG. 1 is a schematic diagram of one embodiment of the method for producing synthesis gas from petroleum coke provided by the present invention. As shown in FIG. 1 , in a horizontal position, four petroleum coke feeding ports 2 are evenly arranged on the side wall of the fluidized bed gasifier 1 . The petroleum coke particles enter the fluidized bed from the petroleum coke feed port 2 through a screw feeder or a lock hopper. A horizontal gas distribution plate is arranged at the bottom of the gasifier, and an appropriate number of caps 5 are distributed on the gas distribution plate to change the gas flow direction to make the gas flow in the bed more uniform. The gasification agent is fully mixed by the gas mixer 6, uniformly distributed in the gas buffer chamber 7, enters the bottom of the fluidized bed from the cap 5, and reacts with the petroleum coke particles. The reactant gas flows out of the gasifier from the reactant outlet 3 at the top of the fluidized bed gasifier, and is connected to a high temperature cyclone separator for separation. The obtained gas phase material is cooled and dedusted to obtain synthesis gas. Part of the fine powder coke is collected from the fluidized bed gasifier by the collector 4 and extracted through the fine powder coke discharge port 8, and collected outside the fluidized bed gasifier to recover the metal rich in the fine powder coke. Manhole 9 is used for installation and maintenance.

The present invention is further described below in conjunction with the examples, but the present invention is not limited in any way.

Example 1

In this example, a fluidized bed gasifier is used, the height of the fluidized bed is 9.5 m, the petcoke feed port is set at 37% of the height of the fluidized bed, and four are set on average along the side wall; The powder coke discharge port is set at 59% of the height of the fluidized bed.

The properties of the petroleum coke 1 treated in this example are shown in Table 1, and the metal content of the ash 1 in the petroleum coke 1 is shown in Table 2. The average particle size of the petroleum coke 1 is 500 μm, and in the petroleum coke 1, in terms of weight percentage, the ash content is 0.91%, the metal content is 0.43%, and the vanadium content is 0.01128%. In this embodiment, the gasification agent is composed of water vapor and oxygen, and the volume content of water vapor is 75%.

The gasification reaction conditions are as follows: the reaction temperature is 1000°C, the reaction pressure is 0.5MPa, and the feed amount of petroleum coke 1 is 120t/h. The volumetric space velocity of the vaporizing agent gas was 510.1 h ⁻¹ .

The reaction gas flows out of the gasifier from the top of the fluidized-bed gasifier, and is connected to a high-temperature cyclone separator for separation. The obtained gas-phase material is cooled and dedusted to obtain synthesis gas. Part of the fine powder coke is drawn out from the fine powder coke discharge port. The resulting wet-based product gas flow was 380,700 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 82.3%. The flow rate of collecting fine powder coke is 7.1t/h, and the particle size is less than 0.12mm. Among them, in terms of weight percentage, the ash content of the fine coke is 10.7%, the total metal content of the fine coke is 5.16%, and the vanadium content of the fine coke is 0.13%.

Table 1 Petroleum coke composition (%)

Table 2 Ash metal content (%)

serial number Ni V Na Al Fe Cu Ca 1 4.28 1.24 12.7 7.2 18.7 0.056 4.1 2 4.15 1.32 11.5 6.9 17.4 0.043 5.9

Example 2

The same fluidized bed gasifier, the same petroleum coke feedstock and gasification agent were used as in Example 1.

The gasification reaction conditions were as follows: the reaction temperature was 950°C, the reaction pressure was 0.5MPa, and the feed rate of 1 petroleum coke was 100t/h. The volumetric space velocity of the gasifying agent gas was 420.3 h ^-1 .

The resulting wet-based product gas flow was 317,000 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 80.3%. The flow rate of collecting fine powder coke is 5.7t/h, and the particle size is less than 0.10mm. The ash content of the fine coke is 9.3%, the metal content of the fine coke is 4.48%, and the vanadium content of the fine coke is 0.11% by weight percentage.

Example 3

The same fluidized bed gasifier, the same petroleum coke feedstock and gasification agent were used as in Example 1.

The gasification reaction conditions are as follows: the reaction temperature is 1100°C, the reaction pressure is 0.5MPa, the feed amount of petroleum coke 1 is 135t/h, and the volumetric space velocity of the gasification agent gas is 570.5h ^-1 .

The resulting wet-based product gas flow was 428,200 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 87.3%. The flow rate of collecting fine powder coke is 8.2t/h, and the particle size is less than 0.11mm. Among them, the ash content of the fine powder coke is 11.3%, the metal content of the fine powder coke is 5.44%, and the vanadium content of the fine powder coke is 0.13% by weight percentage.

Example 4

In this example, a fluidized bed gasifier is used, the height of the fluidized bed is 7.5 m, the petcoke feed port is set at 41% of the height of the fluidized bed, and four are set on average along the side wall; The powder coke discharge port is set at 57.5% of the height of the fluidized bed.

The same petroleum coke raw material and gasification agent as in Example 1 were used.

The gasification reaction conditions were as follows: the reaction temperature was 1000°C, the reaction pressure was 3.5MPa, and the feed rate of 1 petroleum coke was 110t/h. The volumetric space velocity of the gasifying agent gas was 520.3 h ^-1 .

The resulting wet-based product gas flow was 620,056.7 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 82.3%. The flow rate of collecting fine powder coke is 6.1t/h, and the particle size is less than 0.12mm. The ash content of the fine powder coke is 10.3%, the metal content of the fine powder coke is 4.95%, and the vanadium content of the fine powder coke is 0.12% by weight percentage.

Example 5

The same fluidized bed gasifier as in Example 1 was used.

The properties of the petroleum coke 2 treated in this example are shown in Table 1, and the metal content of the ash 2 in the petroleum coke 2 is shown in Table 2. The average particle size of the petroleum coke 2 is 500 μm. In the petroleum coke 2, in terms of weight percentage, the ash content is 0.87%, the metal content is 0.41%, and the vanadium content is 0.01148%.

In this embodiment, the gasifying agent is composed of water vapor and oxygen, and the volume content of water vapor is 75%.

The gasification reaction conditions were as follows: the reaction temperature was 1000°C, the reaction pressure was 0.5MPa, the feed rate of petroleum coke 2 was 120t/h, and the volumetric space velocity of the gasification agent gas was 510.1h ^-1 .

The resulting wet-based product gas flow was 380,700 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 82.3%. The flow rate of the collected fine powder coke is 7.0t/h, and the particle size is less than 0.10mm. Among them, in terms of weight percentage, the ash content of the fine coke is 9.7%, the metal content of the fine coke is 4.57%, and the vanadium content of the fine coke is 0.128%.

Example 6

The same fluidized bed gasifier, the same petroleum coke feedstock and gasification agent were used as in Example 1. The difference is that the average particle size of the treated petroleum coke 1 is 600 μm.

The gasification reaction conditions are as follows: the reaction temperature is 1000°C, the reaction pressure is 0.5MPa, and the feed rate of 1 petroleum coke is 110t/h. The volumetric space velocity of the vaporizing agent gas was 510.1 h ⁻¹ .

The resulting wet-based product gas flow was 350,700 Nm ³ /h. The volume content of CO+ _H2 in the dry base gas is 82.3%. The flow rate of the collected fine powder coke is 7.0t/h, and the particle size is less than 0.12mm. Among them, in terms of weight percentage, the ash content of the fine coke is 10.9%, the metal content of the fine coke is 5.26%, and the vanadium content of the fine coke is 0.13%.

Example 7

The same fluidized bed gasifier as in Example 1 was used, and the same petroleum coke raw material was used.

In this embodiment, the gasification agent is composed of water vapor, carbon dioxide and oxygen, wherein the volume content of water vapor is 40%, and the volume content of carbon dioxide is 35%.

The gasification reaction conditions are as follows: the reaction temperature is 1000°C, the reaction pressure is 0.5MPa, and the feed amount of petroleum coke 1 is 120t/h. The volumetric space velocity of the vaporizing agent gas was 510.1 h ⁻¹ .

The resulting wet-based product gas flow was 370,700 Nm ³ /h. The volume content of CO+ _H2 in the dry gas was 81.3%. The flow rate of collecting fine powder coke is 7.1t/h, and the particle size is less than 0.12mm. Among them, the ash content of the fine powder coke is 10.7%, the metal content of the fine powder coke is 5.16%, and the vanadium content of the fine powder coke is 0.13% by weight percentage.

It should be noted that the above descriptions are only arbitrary embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (12)

1. A method of producing syngas from petroleum coke, comprising: petroleum coke particles enter the fluidized bed gasification furnace from a petroleum coke feeding port of the fluidized bed gasification furnace, a gasification agent enters the fluidized bed gasification furnace from a gasification agent feeding port at the bottom of the fluidized bed gasification furnace, the petroleum coke particles are contacted with the gasification agent under the gasification reaction condition to carry out gasification reaction, a gasification reaction product is extracted from a reactant outlet at the top of the fluidized bed gasification furnace, synthesis gas is obtained after separation, part of fine coke powder is extracted from a fine coke powder discharging port of the fluidized bed gasification furnace and collected, the vanadium content of the obtained fine coke powder is not less than 0.1 wt%, and the fine coke powder discharging port is arranged on the side wall of the fluidized bed gasification furnace and is positioned above the petroleum coke feeding port.

2. The method of claim 1, wherein the petroleum coke is from a delayed coking process, and the particle size of the petroleum coke particles entering the fluidized bed gasifier is 0.1-3 mm.

3. The process according to claim 2, wherein the petroleum coke particles have a particle size of 0.1 to 1.5mm, preferably 0.1 to 1.0 mm.

4. The process of claim 1, wherein the gasification reaction conditions are: the reaction temperature is 800-1300 ℃, the reaction pressure is 0.1-5.0 MPa, and the retention time of petroleum coke particles is 20-60 min.

5. The process according to claim 4, wherein the reaction temperature is 900 to 1200 ℃, preferably 1000 to 1100 ℃.

6. The method according to claim 1, wherein a gas distribution plate is provided above a gasification agent feed port of the fluidized-bed gasification furnace, gas outlets are provided on the gas distribution plate, the gas velocity of the gas outlets is 1 to 5m/s, and the empty bed gas velocity of the fluidized bed is 0.2 to 1.0 m/s.

7. The method according to claim 1, wherein the height of the fluidized bed in the fluidized-bed gasification furnace is 5 to 20m, preferably 6 to 10 m.

8. The method of claim 1 or 7, wherein the petroleum coke feed inlet is arranged at 1/3-2/3 of the bed height of the fluidized bed; the fine coke discharging port is arranged at 1/2-5/6 of the height of the bed layer of the fluidized bed; the petroleum coke feed inlets are arranged on the side wall of the fluidized bed gasification furnace in an amount of 1-6.

9. The method according to claim 1, wherein the fine coke breeze has a particle size of 0.02 to 0.2mm and a vanadium content of 0.1 to 2.1 wt.%.

10. The method according to claim 1, characterized in that the gasifying agent is a mixed gas I of water vapor and oxygen, and the molar content of the water vapor in the mixed gas I is 50-85%; or the gasifying agent is a mixed gas II of water vapor and air, and the molar content of the water vapor in the mixed gas II is 5-20%.

11. The method according to claim 1, wherein the mixed gas I or II contains carbon dioxide, and the molar content of the carbon dioxide in the mixed gas I is 10-30%, and the molar content of the water vapor in the mixed gas I is 20-65%; in the mixed gas II, the molar content of carbon dioxide is 10-30%, and the molar content of water vapor is 5-10%.

12. The method according to claim 1, wherein the feeding temperature of the gasifying agent is 100 to 500 ℃.

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