Carbonaceous substance gasification device and method

Abstract

A carbonaceous substance dry powder gasification device and method, the device comprising from bottom to top a lower cooling and purification section (1), a gasification reaction section (2), a cooling reaction section (3) and an upper cooling and purification section (4); an initial cooling device is disposed at the connection between the cooling reaction section and the gasification reaction section; and a plurality of nozzles are circumferentially arranged in the gasification reaction section. The method comprises: a gasification reaction is conducted between a carbonaceous substance and an oxygenated gasifying agent to generate crude synthesis gas and ash; part of the crude synthesis gas and most of the ash go downstream for cooling and gasification, and the cooled and ash removed crude synthesis gas is transferred to subsequent processes, and the quenched ash is discharged through an ash outlet; the remaining crude synthesis gas and fly ash go upstream to mix with a cooling substance for cooling, and then are transferred to the cooling reaction section for reacting with the incompletely reacted carbon and added gasification agent; the crude synthesis gas and the fly ash are cooled and purified to remove the fly ash, and the clean low-temperature crude synthesis gas is transferred to subsequent processes. The method avoids ash blocking at an ash outlet in an upstream air-exhaust method, and also avoids overheating at the top in a downstream air-exhaust method, thus improving the carbon conversion rate.

Claims

1. A method for carbonaceous substance powder gasification in a vertical device, comprising the steps of: i) reacting a carbonaceous substance in powder form in a vertical device with an oxygen-containing gasification agent at a temperature which generates a crude synthesis gas comprising CO, H.sub.2, and ash; ii) allowing a first portion of said crude synthesis gas to descend with most of the ash wherein the heat of the crude synthesis gas prevents buildup of slag; iii) removing the ash from said first portion of crude synthesis gas and cooling to form a first purified synthesis gas; iv) removing said first purified synthesis gas and removing said ash from the bottom of said vertical device; v) simultaneously allowing a second portion of said crude synthesis gas to ascend through said vertical device; vi) mixing said second portion of crude synthesis gas with a cooling material to lower the temperature; vii) submitting the cooled second crude synthesis gas portion to a second oxidation reaction by mixing with an oxygen-containing gasification agent at a lower temperature than step i) to form a reoxidized synthesis gas; viii) cooling said reoxidized synthesis gas and removing the ash to form a second purified synthesis gas; and ix) removing said second purified synthesis gas from the top of said vertical device.

2. The method of carbonaceous substance powder gasification according to claim 1, wherein in step i) multiple nozzles are used to spray the carbonaceous substance and the oxygen-containing gasification agent into a gasification reactor in said vertical device.

3. The method of carbonaceous substance powder gasification according to claim 1, wherein step i) is performed at a temperature between 1200° C. and 2000° C. and a pressure between 0.1 MPa and 11 MPa.

4. The method of carbonaceous substance powder gasification according to claim 1, wherein the volume of partially purified synthesis gas from step v) is about 60%-80% (volume/volume) of the crude synthesis gas formed in step i).

5. The method of carbonaceous substance powder gasification according to claim 1, wherein said oxygen-containing gasification agent is selected from the group consisting of water steam, water mist, CO2, and mixtures of two or more thereof.

6. The method of carbonaceous substance powder gasification according to claim 1, wherein the second oxidation reaction of step vii) is performed at a temperature of about 800° C. up to the softening temperature of the ash.

7. The method of carbonaceous substance powder gasification according to claim 1, further comprising the step of: iv) when an ash slag blockage occurs which causes the pressure to rise, increasing the volume of said first portion of synthesis gas and slowly raising the temperature so that excess slag can be melted, until the pressure returns to normal.

8. The method of claim 1 further comprising the step of delivering said first and/or second purified synthesis gas to subsequent procedures.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

(2) FIG. 1 is an illustrative view of the gasification method of the present invention.

(3) FIG. 2 is an illustrative view of a device of the present invention.

(4) The numbers in the drawings indicate:

(5) 1. bottom cooling purification part or section; 11. downwards rapid cooling device; 12. downstream pipe; 13. bottom synthesis gas outlet; 14. upstream pipe; 15. slag pool; 16. slag outlet; 2. gasification reaction part or section; 21. nozzle; 22. gasification chamber; 23. gasification chamber water cooling wall; 3. cooling reaction part or section; 31. primary cooling device; 4. upper cooling purification part; 41. upstream rapid cooling device; 42. baffle pipe; 43. baffle device; 44. spray device; 45. segregation device; 46. upper synthesis gas outlet; 47. ash pool; 5. shell.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(6) Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the attached drawings, wherein the same reference numerals refer to the same elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein.

Example 1

(7) As shown in FIG. 1, a method of carbonaceous substance powder gasification, characterize in, including the following steps:

(8) Using 8 nozzles to spray the carbonaceous substance-coal powder with the gasification agent-mist of water steam into the gasification reaction part 2 of the equipment, in the environment of high temperature 1200° C. to 1800° C., high pressure of 4.5 MPa, they rapidly react, and create crude synthesis gas whose main components are CO and H2 and ashes whose main components is inorganic substance.

(9) About 25% of the high temperature crude synthesis gas and most of the ashes cinder flow down into the cooling purification part 1, the cleaned and purified crude synthesis gas is then delivered to the following procedures, the quenched ashes cinder are exhausted from the equipment through the cinder exit.

(10) About 75% of the high temperature crude synthesis gas and the high temperature ashes flow up and mix with the water mist to lower the temperature, and then flow into the cooling reaction part 3, at this stage, the carbon which is not fully reacted will again react with the supplemented H.sub.2O, then further improve the carbon conversion and lower the temperature, and the ratio of hydrogen:carbon is also raised.

(11) After the reaction, the crude synthesis gas and the flying ash keep flowing up, is rapidly cooled, and then go into the upper cooling purification part 4, passing through the water bath, tray separation, cyclone separation, etc. to be cooled and purified, eliminate the dust in the crude synthesis gas, then the low temperature crude synthesis gas which is relatively clean will be then delivered to the following procedures.

Example 2

(12) See FIG. 2, a device for carbonaceous substance gasification, characterized in, includes bottom cooling purification part 1, gasification reaction part 2, cooling reaction part 3, upper cooling purification part 4, shell 5.

(13) Said bottom cooling purification part 1 is set at the bottom of the device, its inlet is connected with the lower outlet of gasification reaction part 2. Said bottom cooling purification part 1 includes downwards rapid cooling device 11, downstream pipe 12, bottom synthesis gas outlet 13, upstream pipe 14, slag pool 15, slag outlet 16, etc.

(14) Said gasification reaction part 2 is set at the lower part from the middle of the device. Six nozzles are arranged around the periphery of gasification reaction part 2; nozzles are arranged on one level, the bottom outlet of said gasification reaction part 2 is connected with the bottom cooling purification part 1, and its upper outlet is connected with the cooling reaction part 3.

(15) Said nozzles 21 are arranged so that the sprayed reactant can go in a path which creates a rotary cut (relative to the axis of the nozzle, tangent with a same circle), and it's a rotary cut of the nozzles on the same level.

(16) Said cooling reaction part 3 is set on the upper part from the middle of the device. Its inlet is connected with the upper outlet of the gasification reaction part 2. A primary cooling device 31 is arranged at the connected part, to spray a proper amount of water mist, so that on one hand cooling the gas, and on the other hand complementing the reactant, to further proceed the carbon gasification reaction of the carbon in the ash at the cooling reaction part 3.

(17) After the reaction, the crude synthesis gas keeps going up, passing through the upstream rapid cooling device 41 to be rapidly cooled, then passing through the baffle pipe 42, going into the ash pool 47 to be water bathed, then through the baffle device 43 to separate the big particles in the ash, going through the spray device 44 to be moisturized, then passing the segregation device 45 to remove the particles in the synthesis gas, then from the upper synthesis gas outlet 46 to be delivered to the following procedures.

(18) Said upper cooling purification part 4 is set on the top of the device, its inlet is connected with the outlet of the cooling reaction part 3, it includes the upstream rapid cooling device 41, baffle pipe 42, baffle device 43, spray device 44, segregation device 45, upper synthesis gas outlet 46, ash pool 47, etc.

Example 3

(19) See FIG. 2, a device for carbonaceous substance gasification, characterized in, includes bottom cooling purification part 1, gasification reaction part 2, cooling reaction part 3, upper cooling purification part 4, shell 5.

(20) Said bottom cooling purification part 1 is set at the bottom of the device, its inlet is connected with the lower outlet of gasification reaction part 2. It includes downwards rapid cooling device 11, slag pool, slag outlet, synthesis gas outlet, etc.

(21) Said gasification reaction part 2 is set at the lower part from the middle of the device. Four nozzles are arranged on each level around the periphery of gasification reaction part 2; nozzles are arranged on 2 levels. The bottom outlet of said gasification reaction part 2 is connected with the bottom cooling purification part 1, and its upper outlet is connected with the cooling reaction part 3.

(22) Said nozzles 21 are arranged so that the reactants are sprayed to create a hedge effect (the axis of opposite nozzles coincide), said hedge effect can occurs between nozzles on different levels.

(23) Said cooling reaction part 3 is set on the upper part from the middle of the device. Its inlet is connected with the upper outlet of the gasification reaction part 2. A primary cooling device 31 is arranged at the connected part, to spray a proper amount of water mist, so that on one hand cooling the gas, and on the other hand complementing the reactant, then to further proceed the carbon gasification reaction of the carbon in the ash at the cooling reaction part.

(24) After the reaction, the crude synthesis gas keeps rapid cooling device 41 to be rapidly cooled again, then through the baffle pipe 42, goes into the ash pool 47 to be water bathed, then through the baffle device 43 to separate the big particles in the ash, goes through the spray device 44 to be moisturized, then through the segregation device 45 to remove the particles in the synthesis gas, then from the upper synthesis gas outlet 46 to be delivered to the following procedures.