JPS6010072B2 - Method for producing low viscosity mixed coal oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a low-viscosity mixed coal oil from a mixture of fine particles or powdered coal and petroleum-based heavy oil with a large hydrogen content, such as paraffinic heavy oil or mixed base heavy oil. be.

Finely pulverizing coal and mixing it with heavy oil to form a slurry and turning it into a fluid was advantageous for transport, and research had begun at naval fuel depots since before the war.

That is, a method of washing coal based on the specific gravity of coal was proposed, and heavy oil was mixed with this washed coal to produce a fairly stable mixed coal heavy oil.
Although it was obtained that the coal did not settle completely for about 3 months, it was found that it did not withstand long-term storage, and that it did not mix completely when newly added to heavy oil5.

Thereafter, low-temperature tar was added to the moat coal heavy oil to create a product that could be stored for about a year, and practical combustion experiments were conducted with good results. However, when coal is pulverized and made into an emulsion with tar and heavy oil, the viscosity increases, so it has to be limited to about 100 mesh, resulting in poor stability, and this method is expensive to produce, so it is not practical. Ta. (Navy Fuel Plant History, p. 426) After the oil crisis of the 4th year of the Showa era, research was restarted in Japan, and practical tests are now underway. According to these research reports, the viscosity of Taka coal oil at room temperature is extremely high, and in order to reduce the viscosity to the level of C heavy oil, it is necessary to constantly heat and keep it at 60°C or higher. Next, mixed coal oil (COM) is unstable and when it runs still, the coal separates due to the difference in specific gravity.

To prevent this, it is necessary to use expensive surfactants. The present invention is inspired by the research on the naval fuel depot, and aims to provide a method for producing mixed coal oil in which the two conflicting requirements of mixed coal oil, namely viscosity and stability, can be arbitrarily adjusted. By introducing a thermal decomposition method for heavy oils such as atmospheric residual oil, we can produce high value-added by-products such as white oils such as volatile oil and kerosene oil, as well as high-calorie gases containing 50% or more of methane gas, in high yields. It is intended to provide a method for obtaining the information. When coal is crushed into chunks of 3 or more ribs and heated to 35,000 or more using internal or external heating, thermal polymerization occurs at the same time as thermal decomposition, so the light oil produced by thermal decomposition undergoes a polymerization reaction within the system. The content of volatile oil of 200 qo or less contained in the obtained low-temperature tar is as small as 5% or less.

This heats coal, which is a poor conductor of heat, in the vapor phase.
This is due to two reasons: the time it takes to raise the temperature above 350q0, which is the point at which the decomposition reaction begins, and the difficulty in uniform heating.
The polymerization reaction proceeds more than the decomposition reaction, producing a small amount of light components, a large amount of car tar and semi-formed coke, and the gas contains less methane gas and more hydrogen. The present invention suppresses the polymerization reaction and only suppresses the decomposition reaction by turning coal into fine grains or powder, using petroleum-based heavy oil with a high hydrogen content as a heat medium, and rapidly and uniformly heating the coal to a temperature of 350 pm or higher. We succeeded in progressing the process.

The fact that there is a large amount of methane gas in the by-product gas in the experimental examples described later proves this assumption. Moreover, since most of the volatile components from coal are eluted into heavy petroleum oil and undergo a thermal decomposition reaction, there is a slight risk of over-decomposition due to local heating. The coal that has released most of its volatile content becomes porous semi-formed coke, which has a low bulk specific gravity and is easily compatible with petroleum-based heavy oil, so there is no risk of it settling hard at the bottom of the tower like coal dust. In other words, the mixed coal oil of semi-formed coke is more stable than the mixed coal oil of raw coal. In addition, the low-temperature tar produced from coal acts as a stabilizer, as seen in the history of naval fuel depots, so expensive stabilizers are not required.

To explain the present invention based on the drawings, as shown in FIG. Evenly mixed.

Pulverized coal uniformly mixed with virgin oil is pumped into slurry pump p.
, and pressurized to normal pressure or below 50k9/2, fed into a heating furnace F, heated to a temperature of 350 to 50,000, and sent to a first reaction connection P. In order to replenish the decomposition heat in the first reaction tower R and prevent the polymerization reaction, the steam blood is heated to 60 qo or more in the heating furnace F, and then the steam is heated to 60 qo or more in the first reaction tower R and the second reaction tower R.
Blow into the bottom of 2. Since the heating coil for mixed coal oil in heating furnace F is thought to naturally cause coking, it is preferable to adopt the continuous coking method described in Hakama Kei Sho 55-1 No. 183987 and to switch between the superheated steam coil and the mixed coal oil heating coil at appropriate times. . That is, as shown in Fig. 1, the heating tube of heating furnace F consists of double coils h, h2, and heating tube h is first used to heat mixed coal oil, and heating tube h2 is used to heat steam. After a certain period of time, when coke is generated and the pressure in pump p increases, the feed is switched as shown by the dotted line, and steam or oxygen-containing steam is passed through heating tube h for decoking, and mixed coal is heated through heating tube h2. Perform heating. By performing this switching operation, it becomes possible to perform decoking continuously, and it becomes possible to decompose the car quality mixed coal oil into a low viscosity mixed coal oil. The mixed coal oil that has exited the first reaction tower R is stripped of light components by superheated steam in the second reaction tower R2, and the mixed coal oil of semi-formed coke and heavy oil at the bottom of the tower is extracted out of the system by a slurry pump p2.

The viscosity of the mixed coal oil is adjusted by cutting back an appropriate amount of the bottom oil of the reflux tower Rf or the distillation tower C.

That is, when the temperature is low, such as in the winter, the amount of cutback may be increased, and when the temperature is high in the summer, the amount of cutback may be reduced or eliminated. In this flow sheet, the reaction tower is used in a two-stage series, but it may be used in a switching type when there is a possibility of coke formation and blockage due to excessive scale.

Further, in the reaction tower R2, the carburized oil is decomposed into semi-coke Sc, taken out as shown by the dotted line in Figure 1, mixed with the bottom oil of the distillation tower C in an appropriate ratio, and passed through the crusher p3 to form a mixed coal oil. . Furthermore, if the heavy oil has paraffin groups and is easily decomposed and there is no risk of coking, the number of reaction columns may be one.

The dotted line portion from the coal hopper date c shown in FIG. 1 shows the case where the coal is fine (60 mesh or more, about 3 sides).
The granulated coal leaving the hopper is preheated to around 350 oo in a heater, and is directly fed to the top of the reaction tower R. In this case, the mixed coal oil at the bottom is heated to 400°C or higher in the reaction tower R, and although it becomes muddy, it is completely reduced to micron scale. Since it is difficult to form an id, it is necessary to perform further hot grinding at the outlet of the reaction column R2. In this case, hot grinding can significantly save power compared to cold grinding. Next, an example carried out on a batch bench scale is shown in Table 1, in which a known zinc chloride catalyst was added to coal powder at 5 p atm and 430°C.
The results of the decomposition are shown in Table 2.

Table 1 Thin ○ ○ Ship Example 1 Table 1 shows that 200 mosquitoes of powdered coal of 200 mesh or less (Kitawarabi Kasei Yubari Shintan) were added to 1000 baits of atmospheric residue of Middle Eastern crude oil and heated at a temperature of 500°C. The results of the decomposition are shown in Experiment No. T-25.

In addition, the same equipment is used to prepare amorphous aluminosilicate catalyst (A
The results of liquid phase catalytic cracking at a temperature of 480% are shown in experiment number T-11 for reference.
It was shown to. As clearly seen from Table 1, the yield of cracked oil is 81. AIl0siteK for Sakaki t%
For books, it is 65.25%.

10-15M when coal is dry distilled at low temperature by a known method
3% low-temperature tar is obtained for 200 nails of coal.
If 0 scale tar is obtained, the yield should only increase by 3% for 1000 needles of feedstock oil, but petroleum-based atmospheric residual oil with a high hydrogen content acts as a heat medium and the fine coal powder is heated. It is assumed that the uniform heating facilitated the decomposition reaction and prevented the polymerization reaction, resulting in a remarkable increase in tar yield reaching 50% or more.

The equipment used in the implementation is simple, and the reaction conditions,
It is possible that the liquefaction rate can be improved by improving the structure of the reaction tower. In addition, the yield of cracked gas is experimental number T-1.
In the case of No. 1, it was 9.07%, but in Experiment No. T-25, in which coal was added, it was 5.98%, which was much lower, indicating that the coal undergoes decomposition under mild conditions and that hydrogen is also present in the decomposed gas. The amount of methane gas is 50.24%, which is extremely high. It seems that the liquefaction rate was improved as a result. Next, the obtained semi-formed coke was pulverized and mixed with cracked oil at a ratio of 50:50, and the viscosity of 70oo was measured, and the following results were obtained. Sample number Cracking oil fraction Viscosity at 7.00CI
330℃ or higher 260 cp2 30
0℃ or higher 175 cp3 250℃ or higher
The 140 cp viscometer is a rotating cylindrical type and uses a No. 3 rotor (3 ratio p to 130 ratio p). COM with C heavy oil as the base oil usually has a high viscosity of 100 ratio p or more even at 70°C.
Since the cracked oil of the present invention is comparable to heavy oil A, its viscosity is C, which is known.

It is extremely fluid below M. Sample No. 1 CO
M had good stability and was left at room temperature for about one month, but no hard deposits were formed.

If no surfactant is added to the known COM of coal based on heavy oil A, it will completely separate in about a week, and the resulting product will solidify into a gel and stick to the bottom surface, making it impossible to transport by pump. Example 2 Table 2 shows that pulverized coal and 10% zinc chloride were added or not added to the decant oil, which was produced as a by-product when the light oil content of Daqing crude oil in China was catalytically cracked using an FCC device, with or without addition of pulverized coal and 20% zinc chloride. , 400-450q0, 50k9/earth conditions.

The reaction time was 10 minutes, and the carbon yield was 11.5% for Experiment No. 57.2 without adding coal, and Experiment No. 57.2.
8 and 17 are 20.5% and 57.813 is 21.7% (inner zinc chloride 2%), so if you subtract the 11.5% carbon from the decant oil from the latter, the carbon generated from the coal is 9%. This means that about 50% of the coal has been converted into oil. The features and effects of the present invention are as follows.

01 By thermally decomposing paraffinic or mixed base heavy oil using finely divided coal as a catalyst, cracked oil can be obtained with a high yield of 80% or more.

[2] By introducing a pyrolysis step into the production process of mixed coal oil, white oil with high added value can be obtained at a high yield of 35 to 40%.

{31 The resulting mixed coal oil has low viscosity and good stability because the low-temperature tar produced from the coal acts as a stabilizer.

Does not require expensive surfactants. {4' By changing the operating conditions, it is possible to produce COM with fluidity even in the coldest period (below 5°C).

■ Since white oil and high-calorie gas can be obtained as by-products at a high yield, it is possible to save most of the overhead costs required for producing mixed coal oil, which is extremely advantageous economically.

'6} Semi-formed coke, which has been used as a catalyst by adding zinc chloride to coal, can be made into activated carbon by treating it with steam or air at 700q0 or more.

[Brief explanation of drawings]

The drawings show an overview of the method of the present invention, and FIG. 1 shows its flow sheet. Figure 1

Claims (1)

[Claims] 1. A mixture of fine particles or powdered coal and heavy petroleum oil with a high hydrogen content, with or without the addition of a catalyst, at a temperature of 350°C or higher at normal pressure or pressurization. A low-viscosity mixed coal that is rapidly and uniformly heated at a temperature of 400°C to 550°C and then undergoes a cracking reaction to distill and separate gas, naphtha, and kerosene oil, and to obtain a mixture of low-viscosity cracked heavy oil and semi-finished coke. Method of producing oil. 2. The low viscosity mixed coal oil according to claim 1, wherein the kerosene and light oil fraction distilled and separated is partially returned to the mixture of cracked heavy oil and semi-formed coke to adjust the viscosity of the mixture. manufacturing method. 3 A mixture of fine particles or powdered coal and heavy petroleum oil with a high hydrogen content is heated to 350 ml under normal pressure or pressurization.
400℃~550℃ after rapid uniform heating at a temperature of ℃ or higher
Gas, naphtha, and kerosene oil are distilled and separated by carrying out a cracking reaction at a temperature of A method for producing low viscosity mixed coal oil, which obtains a mixture of low viscosity cracked heavy oil and semi-formed coke by mixing. 4. The method for producing a low-viscosity mixed coal oil according to claim 3, wherein the viscosity of the mixture of low-viscosity cracked heavy oil and semi-formed coke is adjusted by increasing or decreasing the mixing ratio of kerosene and gas oil.