CS218331B1 - A method for producing a generator gas and a controllable amount of carbon black by partial oxidation - Google Patents

Abstract

The invention relates to the production of producer gas with a controllable amount of soot by partial oxidation of petroleum and tar raw materials in the range of b. v. atmospheric and vacuum petroleum residue. The raw material, to which water or an aqueous solution of potassium salts is optionally added, is partially oxidized with a mixture of oxygen and water vapor in more favorable proportions than before. The process is controllable and less energy-intensive.

Description

The invention relates to the production of producer gas with a controllable amount of soot by partial oxidation of petroleum and tar raw materials in the range of b. v. atmospheric and vacuum petroleum residue. The raw material, to which water or an aqueous solution of potassium salts is optionally added, is partially oxidized with a mixture of oxygen and water vapor in more favorable ratios than before. The process is controllable and less energy-intensive.

The invention relates to the production of producer gas with a controllable amount of soot by partial oxidation of petroleum and tar raw materials in the range of atmospheric and vacuum petroleum residue. During partial oxidation of petroleum and tar raw materials with oxygen and steam, producer gas is obtained, which is the starting material for the production of technical hydrogen and synthesis gases for methanol production, olefin oxonation and other syntheses. In the gasification of petroleum raw materials, the usual raw material is atmospheric and vacuum petroleum residue, the addition of oxygen is 0.775 m _n ³ O2 and water vapor 0 _; .531 kg per 1 kg of raw material.

The by-product of partial oxidation is soot, which is washed out of the produced gas generator with pressurized water. This creates soot water, which usually contains 8 to 20 g of soot per liter. The soot is separated from the soot water by so-called pelletization, in which the soot contained is converted into the form of easily separable balls (pellets) using gasoline, kerosene, fuel oil or other petroleum fractions.

In the usual partial oxidation regime, according to long-term evaluation, 18.4 to 21.7 kg of soot is produced per 1 ton of gasified fuel oil, i.e. about 2% by weight.

It has now been found that the amount of soot produced can be regulated as needed by adjusting the operating mode of partial oxidation without major modifications and on already installed pressure generators for partial oxidation.

The method for producing producer gas and a controllable amount of carbon black by partial oxidation of petroleum and tar raw materials in the range of atmospheric and vacuum petroleum residue consists, according to the invention, in that the raw material, to which water or an aqueous solution of potassium salts, e.g. potassium carbonate, is optionally added in an amount of 0.5 to 5% by weight, preferably 1 to 2% by weight, is partially oxidized by adding oxygen in an amount of 0.7 to 0.75 m _n ³ O2 and water vapor in an amount of 0.33 to 0.51 kg, calculated per 1 kg of raw material.

In an attempt to reduce the proportion of soot produced, it is desirable to add potassium salts, preferably potassium carbonate, to the dosing water in an amount of up to 100 mg of potassium carbonate per 1 kg of gasified fuel oil.

It is possible to operate in the range of 1300 to 1400 °C, preferably at 1320 to 1350 °C, which is conditioned by the quality of the protective lining of the gasification generators. The invention is demonstrated by the following examples.

Example 1

The results of the experiments were compared with the usual working conditions of partial oxidation of fuel oil, in which about 50% of the soot produced was recycled to the generator. The test results are given in Table 1.

It is clear that the soot yield was controlled and achieved a soot yield twice as high as usual. Under the above conditions ^, about 28,000 _m3 /h of producer gas of the usual composition, i.e.

CO2 content % CO content % Ha content % CH4 content °/o Na + Ar content % H2S and COS content %

obj. 4.8 - 5.4 obj. 45.2 — 46.2 obj. 46.9 — 48.5 obj. 0.17 — 0.35 obj. 1.2 - 1.8 obj. 0.5 — 0.6

Water added additionally to the gasified fuel oil can be added to the suction of the pump dosing the fuel oil to the generator and/or to the pipeline feeding the fuel oil through the preheater heating the fuel oil to 200 to 250 °C to the spray nozzle in the partial oxidation generator.

When recirculating soot, for example, by 25 or 50%, it has proven effective to dose water into the generator so that the resulting soot and fuel oil suspension contains 1 to 2.5% water.

If there is an interest in reducing the amount of soot produced below the usual value, i.e. about 145 to 180 kg of soot per hour when gasifying 9.5 tons of fuel oil, it is desirable to dose a diluted solution of potassium carbonate or other potassium salt instead of water alone. If the amount of potassium carbonate dosed did not exceed 100 mg/kg of gasified fuel oil, no problems were observed during partial oxidation.

Table No. 1

Results of operational tests in which the amount of soot falling off was regulated

Amount of fuel oil t/h

Carbon black recycling

Temperature in the generator °C

Pressure

MPa

Amount of water dosed kg/h

Amount of soot transferred to soot water kg/h

Gasified oxygen m _n ³ kg raw material ratios Steam kg/kg raw material

Usual 9.42 partial conditions oxidation: 3.50 147 0.754 0.531 50 1320 Experimental conditions: 10.18 50 1350 3.60 150 335 0.747 0.510 9.73 none 1350 3.45 170 269 0.725 0.502 10.01 25 1350 3.58 90 372 0.739 0.468 10.18 25 1320 3.58 150 280 0.698 0.500 10.18 25 1400 3.58 150 243 0.747 0.334 9.61 50 1350 3.50 120 280 0.728 0.500 10.32 none 1350 3.62 none 201 0.736 0.508 10.00 none 1400 3.58 150 230 0.748 0.350 10.10 none 1350 3.60 160 290 0.745 0.438 10.10 none 1350 3.60 160 people 90 0.747 0.510 0.7 kg K2CO3 9.68 none 1320 3.48 100 289 0.730 0.490 Example 2 heat exchange surfaces in a waste heat boiler and this allows extend working ·

Table 2 shows the amount of soot produced and the operating conditions. In an operating mode where less soot is produced, the heat exchangers become clogged more slowly between cleanings; this made it possible to extend the operating cycle from, for example, 700 hours to 1000 hours.

Table No. 2

Data on reduced and increased soot production

Current status Newly proposed status less soot more soot

temperature in the generator °C 1320 — 1340 1400 1350 pressure in the generator, MPa 3.58 3.58 3.58 amount of dosed oxygen ra,, ⁵ per kg of fuel oil 0.754 0.7 until 0.75 0.728 amount of process steam kg per kg of fuel oil 0.531 0.445 0.520 0.480

amount of water dosed into the generator % by weight 1.5 1.5 amount of water dosed into the generator + amount of water in the soot recycle % by weight 2.5 2.5 total amount of steam and water dosed into the generator

kg/kg of fuel oil 0.54 0.471 0.504 amount of soot produced per 1 ton of fuel oil kg 18.4 to 21.7 13.2 to 15.9 29.7

The interest in producing a larger amount of carbon black as a by-product of partial oxidation is when the carbon black is purposefully separated from the carbon black water and further utilized.

Isolated carbon black with a surface area of 600 to 1500 ^m2 /g can be used for wastewater treatment, for the production of electrodes, as a filler for plastics such as polyethylene and polypropylene, as electrically conductive carbon black, etc.

If soot isolation is not operationally implemented, or only a portion of the soot is sold, it is desirable to reduce soot production and thus reduce the specific consumption of fuel oil or vacuum oil residue.

Claims (1)

SUBJECT A method for producing generator gas and a controllable amount of carbon black by partial oxidation of petroleum and tar feedstocks within the boiling range of atmospheric and vacuum oil residues with the addition of oxygen and water vapor, characterized in that the feedstock to which water or water is optionally added potassium carbonate in an amount of 0.5 to 5 wt.%, preferably about 1-2 / ₀ wt., are partially oxidized by adding oxygen in an amount of 0.7 to 0.75 m _N ⁵ O 2 and water vapor at 0.33 to 0,51 kilograms per 1 kg of raw material.