JPS63171804A - Utilization of oxygen blast furnace gas - Google Patents

Abstract

PURPOSE:To produce substitution gas of natural gas, which can utilize as fuel gas for various uses, by treating de-CO, de-S after removing dust in oxygen blast furnace gas and removing the impurities by reaction of adjusted H2/CO ratio. CONSTITUTION:After removing the dust in the oxygen blast furnace gas 1 obtd. from the furnace top of oxygen blast furnace 10 by a rough dust collector 2, a part of the gas is used to preheating of raw material charged in the oxygen blast furnace 10. After the remaining part of gas is treated by supplying successively to de-S mechanism 5 and de-CO mechanism 6 through a pressurized sending mechanism 10, H2/CO ratio is adjusted by H2 source introducing device 16. Next, after reacting the gas by supplying to a reaction tower 8 through the pressurized rising mechanism 7, it is supplied to an impurity remover 15 through a cooler 9, to remove the impurities and make the production gas 11. In this way, the substitute fuel gas having about 10,000-11,000kcal/Nm<3> is obtd.

Description

[Detailed description of the invention] "Purpose of invention" (Industrial application field) Technology for processing and utilizing blast furnace gas generated from oxygen blast furnaces.

(Prior art) Advantageous operations can be achieved by injecting high-concentration oxygen through the blast furnace tuyere, and such a method is described in JP-A-60-159104. .

(Problems to be solved by the invention) The blast furnace gas generated from the conventional oxygen blast furnace as described above is
Generally, it has a calorific value of 1,300 to 2,000 Kcal and 17 Nnf, which is higher than that of blast furnace gas generated from an ordinary blast furnace, so it is extremely difficult to use this oxygen blast furnace gas in a recovery and utilization system for ordinary blast furnace gas.

Therefore, it is conceivable to utilize this oxygen blast furnace gas by providing a completely separate storage or piping facility, but this would require enormous equipment costs and would be practically difficult.

"Structure of the Invention" (Means for Solving the Problems) The present invention was devised to solve the problems of the conventional products as described above. This is a method of utilizing oxygen blast furnace gas, which is characterized in that it undergoes S removal treatment, and then sends the gas with an adjusted H2/CO ratio to a reaction tower for reaction, removes impurities, and obtains an alternative natural gas.

(Function) By removing CO, that is, adjusting C, and removing S from the oxygen blast furnace gas which has been reduced to coarse dust, a reduction in activity due to poisoning of the reaction catalyst in the latter reaction tower is avoided.

Also, CO is removed by H2 gas, coke oven gas, steam, etc.
By adjusting the ratio of H2 and H2, for example, if the H2/CO ratio is large, it is advantageous for methane production, and if this ratio is small, it becomes easier to produce 02 hydrocarbons such as ethane and propane. control is possible.

Furthermore, in a reaction tower, for example, 20 to 30 kg/aJ, 300 to
Hydrocarbonization reaction by reacting under operating conditions of 500℃ GO+3Hz -'CH4+H20,2CO
+2H! -CH4+co*, Co2+4H2-'CH
4+2H! O, CO+H! 0-4CO2+)(,) and further increases the amount of heat.

Removal of impurities such as CO1CO□ and Nz s Hz in the reaction tower outlet gas (possibly 10,000 to 11,000
A preferable alternative fuel gas of about Kcal/Nrrr is obtained.

That is, as a result of various studies on the preferable use of the oxygen blast furnace gas as described above, the present inventors found that the oxygen blast furnace gas has a low Ni content and the main components are Co, co, and H2. Among the oxygen blast furnace gas components, C
It was confirmed that natural gas can be easily substituted by removing O and 8% and adjusting the ratio of CO and H2 using H2 gas, coke oven gas, steam, etc.

The above-mentioned CO removal can be appropriately carried out by an adsorption method, a solution adsorption method, or the like. Further, the removal of S can be accurately achieved by a hydrogenation adsorption method or the like. Regarding the ratio of Co and H2, the Hz/Co ratio is generally set to about 2.6 to 4.5. That is, when H,/Co is less than 266, carbonaceous deposits 2CO→CO□+C are formed on the surface of the catalyst, which significantly reduces the activity of the catalyst. Also, when this Ht/Co exceeds 4.5, the generated gas has the target calorie (11000Kcal/Nrr
r), and the amount of LPG used to increase calories increases, leading to an increase in manufacturing costs. The operating conditions in the reaction tower are generally 20-30 kJr/- and 300-500°C. That is, if the pressure is less than 20 -/-, carbonaceous substances will precipitate, and if the pressure is high, the power cost will increase, leading to high manufacturing costs. If the temperature is 500°C or higher, the progress of the hydrocarbonization reaction will be slow.

Further, in order to lower the temperature to 300° C. or lower, a large amount of cooling water is required, which increases the power cost. Note that in the reaction tower, N
The reaction is carried out using an i-based, Ru-based, or Co-based catalyst.

The outline of the equipment for carrying out the method of the present invention as described above will be explained with reference to the attached drawings. After the oxygen blast furnace gas 1 obtained from the top of the oxygen blast furnace 10 is removed by the coarse confectionery machine 2, a part of it is combusted. Oxygen and the like are suitably added and combusted in the vessel 3 to raise the temperature and then supplied to the shaft portion of the oxygen blast furnace 10 to preheat the raw material charged into the oxygen blast furnace 10. The remainder of the oxygen blast furnace gas 1 discharged from the oxygen blast furnace 10 and crushed into dust is sequentially supplied to a de-S mechanism 5 and a de-CO mechanism 6 via a pressure-feeding mechanism 4, and the de-CO mechanism 6 is a pressure increasing mechanism such as a compressor. 7 and a reaction tower 8 via an H2 source introduction device 16. The reaction tower 8 is connected to an impurity remover 15 via a cooling mechanism 9, so that a product gas 11 can be obtained.

The above-mentioned CO removal mechanism 6 is also connected to a partial combustor 12, and the partially combusted material by adding oxygen or the like generates electric power in the furnace top gas generator 13. blast furnace gas (800Kcaj2
/No? ) The gas whose calorie has been reduced to the level of
4.

(Example) To explain the results of a concrete operation using the above-mentioned equipment, a blast furnace 1 with an iron output of 5QOOt/day
Oxygen gas with a purity of about 95% (6880 H'jrrr/h) was charged from the tuyeres.
62,500 kg/hr of pulverized coal and 62,500 kg/hr of pulverized coal were blown into the furnace, and the blast furnace gas from the top of the furnace was combusted in the combustor 3 while blowing air, and the resulting mixture was brought to about 1000°C and then blown into the shaft to preheat the charging material. It was operated while That is, the composition of the blast furnace gas at this time is c.

is 48.5%, CO is 36.8%, and 1740
Kcaj! /Nnf.

Items other than those sent to the blast furnace gas combustor 3 1000
0 Nrrr/hr is H2 gas 380ONrrr/h from the H2 source introducing device 16 after CO and S removal processing.
The Hx /Co ratio was adjusted to 3.5, the pressure was increased to about 25 kg/aj by the pressure increasing mechanism 7, and the pressure was increased to the reaction tower 8.

In the reaction tower 8, reaction treatment is carried out using a Ni catalyst at 23 kg/cd and 380°C, and the reaction tower outlet gas at 490°C is cooled to 40°C in the cooler 9, and then sent to the impurity remover 1.
At 5, CO! , Nt , Hz , and G 2 O were removed by adsorption to obtain a product fuel gas having a calorific value of 10,500 KcallNrd.

In this case, for the gas entering the pressure boosting mechanism 7,
4550 Kcaj! /Nnf coke oven gas 500
When adding 0 Nrrf/hr and water vapor of 2300 kg/H, the calorific value of the product gas obtained is 11080 K.
cal/Nrrr, and the amount is 3580 Nrr
It became r/hr. The composition of the product gas is CH482,5
%, CaH213.5%, C3H112.5%, C4H
I01.0%, Hzo, 5%.

In addition, 132,100 Nrrf/hr of the oxygen blast furnace gas is added to the oxygen blast furnace gas at a rate of 14,900 Nrrf/hr in the partial combustor 12 and partially combusted, and then the furnace top gas generator 13 generates electricity, thereby generating 14,300 Kw/hr of electric power. Moreover, the gas at the level of normal blast furnace gas, which is about 800 Kcal/Nrrr, is 35400ONITr/hr.
This gas could be used by mixing it into the existing blast furnace gas equipment.

"Effects of the Invention" According to the present invention as explained above, gas generated from an oxygen blast furnace can be used to obtain alternative natural gas, and this can be used as a fuel gas for various purposes. It should be said that this invention is also used for the purpose of producing fuel gas, and it is natural that an advantageous oxygen blast furnace operation can be achieved, and this invention is industrially highly effective.

[Brief explanation of the drawing]

The drawings show the technical content of the present invention, and are explanatory diagrams showing an outline of equipment for implementing the method of the present invention. However, in this drawing, ■ is oxygen blast furnace gas, 2 is a coarse powder, 3 is a combustion machine, 4 is a pressure feeding mechanism, 5 is a de-S mechanism, 6 is a de-CO mechanism, 7 is a pressure boosting mechanism, 8 is a reaction tower, 9 is a cooler;
1O is the oxygen blast furnace, 11 is the product gas, 12 is the partial combustor, 1
3 is a furnace top gas generator, 14 is a normal blast furnace gas utilization line,
15 is an impurity removal mechanism, and 16 is an H2 source introduction mechanism.

Claims (2)

[Claims] (1) CO and S removal after rough dust collection of oxygen blast furnace gas
1. A method of utilizing oxygen blast furnace gas, which comprises treating the gas, and then sending the gas with an adjusted H_2/CO ratio to a reaction tower for reaction to remove impurities and obtain alternative natural gas. (2) A method for utilizing oxygen blast furnace gas as set forth in claim 1, in which the H_2/CO ratio is adjusted and coke oven gas is added and sent to a reaction tower for reaction.