JPS6140719B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a mixture of pulverized coal and a hydrocarbon oil, that is, a mixed coal oil, in which the dispersed pulverized coal has excellent stability and does not settle or solidify over a long period of time. Since coal is a solid, it has traditionally been inferior to fuel oil, which is a liquid, as an energy source because it is difficult to transport and difficult to control during combustion. In order to overcome this problem and improve the suitability of coal as a fuel, various studies have been conducted on mixed coal oils in which finely pulverized coal is dispersed in fuel oil. In Japan, prior to World War II, research into so-called colloidal fuel, which was made by turning coal into pulverized coal and mixing it with petroleum, was being actively conducted at naval fuel depots.However, pulverized coal with a normal particle size distribution and If the coal particles are simply mixed with oil, the difference in specific gravity will cause the coal particles to settle and separate, creating a hard layer with no fluidity.To prevent this, constant stirring or reducing the total amount of coal particles to a diameter of 10μ or less is required Methods of extremely slowing down the sedimentation rate have been considered, but these methods are expensive and unpractical. On the other hand, in order to prevent pulverized coal from settling, many methods have been studied to produce stable mixed coal oil or emulsified mixed coal oil by adding stabilizers such as polymeric substances or emulsifiers and/or water to petroleum and pulverized coal. It has been. Typical stabilizers that have traditionally been used above include protective glues such as glue, gelatin, gum arabic, and starch, as well as paraffin, sericin, lanolin, petrolatum, and similar substances. Examples include wax, beef tallow, and wool tallow. However, although all of these stabilizers have some stabilizing power, they are not decisively effective. Later, metallic fatty acid soaps were considered. The metals of these metal soaps include Al, Mn, Co, Zn, Ca, Na, K, Pb, Mg.
The fatty acids used included oleic acid, stearic acid, and palmitic acid. In addition, there is a method of adding an alkali to form a salt with humic acid in coal to prevent sedimentation of coal particles, and a method of using coal-based distillate such as anthracene, naphthalene, phenanthrene, etc. for the purpose of peptizing and dispersing coal particles. Numerous research examples have been reported in the past, including methods for producing stable mixed coal oil by adding appropriate amounts of tar oil containing phenols, anthracene oil, creosote oil, etc. Recently, an energy crisis has occurred due to production adjustments and high price offensives in Middle Eastern oil-producing countries, which are major suppliers of oil resources.This has triggered calls for global energy diversification, and There are calls for a review of the energy demand structure. Therefore, blended coal oil has also started to attract a lot of attention from the perspective of saving consumption of petroleum resources and making effective use of coal, and many examples of research and inventions have come to be seen. Some of these published materials include a method in which an electric field is applied to a heavy oil dispersion system of pulverized coal to reduce the sedimentation speed of pulverized coal by utilizing thickening due to the electrorheological effect, and the present inventor et al. previously applied for a method in which pulverized coal contains about 3% ultra-fine coal with a particle size of 5μ or less to prevent large particles from contacting each other and make it difficult for them to settle densely, without using stabilizers. Research has also been conducted on methods for producing stable mixed coal oil, but most of the research and invention examples use stabilizers for mixed coal oil, and most of them are particularly related to research on stabilizers. . However, adding a large amount of stabilizer improves the stability of the blended coal oil, but it is a major factor in increasing costs, so it is necessary to stabilize the amount so that it can still function sufficiently even if the amount added is kept to a very small amount. The development of new agents is desired. For example, various imidazoline surfactants, bisamide compounds, ether amine derivatives, alkylphenol surfactants, the aforementioned metal soaps,
and a metal salt of a carboxyl group-containing hydrocarbon,
Polyethylene glycol nonionic surfactant,
A wide variety of additives have been devised, including alkylene oxide derivatives of various compounds with active hydrogen, alkylaryl sulfonic acid type anionic surfactants, dialkyl sulfosuccinate salts, and even more high-performance stabilizers will continue to be developed. I think that the. As mentioned above, research to date has focused on research on coal particles as a dispersoid and the selection of stabilizers, and there has been little detailed research on fuel oil as a dispersion medium. . In general, hydrocarbons are broadly classified into paraffinic, olefinic, naphthenic, and aromatic hydrocarbons. Paraffinic hydrocarbons are saturated chain compounds expressed by the molecular formula of CnH ₂ n+ ₂ (n = integer), and include unbranched n-paraffins and branched isoparaffins, but in light distillates, paraffinic hydrocarbons The content of is relatively high. In addition, olefinic hydrocarbons have only one double bond.
For example, in the case of one double bond,
It is a chain unsaturated hydrocarbon represented by the general formula C _o H _2o (n=integer). Olefins generally do not exist in crude oil, and are hardly included in other petroleum products other than gasoline. In addition, there are diolefins and cyclic olefins, but they are hardly contained in petroleum products. Naphthenic hydrocarbons are hydrocarbons containing at least one saturated ring in one molecule. Naphthene groups present in crude oil and petroleum products are
They are available individually or fused with aromatic rings, as well as naphthene rings, fused rings, and various paraffin side chains. Aromatic hydrocarbons refer to hydrocarbons containing at least one aromatic ring in one molecule, and light distillates are mainly composed of benzene and monocyclic compounds with side chains attached to benzene. In addition, the main components of petroleum heavy fractions are 2- and 3-ring polycyclic condensed aromatic compounds and compounds containing both aromatic rings and naphthenic rings. The components of crude oil, kerosene, light oil, A heavy oil, B heavy oil, C heavy oil, etc. that we currently use as fuel are mainly paraffinic hydrocarbons, naphthenic hydrocarbons, and aromatic hydrocarbons, as is clear from component analysis. It contains almost no olefinic hydrocarbons and organic oxygen. In consideration of the above-mentioned situation, the present inventors prepared various hydrocarbon oils from petroleum hydrocarbons with compositions that did not exist before, and studied the stability of mixed coal oil using these. As a result, the following composition was obtained. It has been discovered that when a hydrocarbon oil having 0.05% is mixed with pulverized coal, an extremely stable mixed coal oil can be obtained without using expensive additives such as surfactants. That is, the present inventors had previously discovered that oxidized oil is extremely effective when mixed coal oil is used as a stabilizer (see Japanese Patent Application No. 53-36747 (Japanese Patent Publication No. 60-23799)); It has been found that olefinic hydrocarbons having 8 or more carbon atoms have similar effects. That is, as a result of various studies on organic oxygen compounds, the present inventors found that organic oxygen compounds having a carbonyl group that exhibits strong absorption in the infrared absorption spectrum near 1630 to 1750 cm ^-1 , such as organic acids, ketones, aldehydes, and acid amides. , acid imide,
Acid thiols are particularly effective and should be mixed with pulverized coal using a hydrocarbon oil containing at least 0.5 weight percent of this type of organic oxygen and at least 5 volume percent of olefinic hydrocarbons having 8 or more carbon atoms. It was discovered that an extremely stable mixed coal oil can be obtained. On the other hand, since olefinic hydrocarbons are easily oxidized, hydrocarbon oils containing olefinic hydrocarbons can be efficiently partially oxidized by auto-oxidation or other methods to generate carbonyl groups and generate organic oxygen. It is also possible to utilize compounds and residual olefinic hydrocarbons. As mentioned above, petroleum-based hydrocarbons contain almost no organic oxygen compounds, so the present invention can obtain a highly stable mixed coal oil using the following hydrocarbon-based oils. (1) As mentioned above, an olefinic hydrocarbon having 8 or more carbon atoms and an organic oxygen compound are added to a liquid oil that does not contain an olefinic hydrocarbon. (2) Organic oxygen compounds are added to liquid oil containing olefinic hydrocarbons having 8 or more carbon atoms. (3) Partially oxidized liquid oil containing olefinic hydrocarbons having 8 or more carbon atoms. (4) Hydrocarbon oil containing an olefinic hydrocarbon having 8 or more carbon atoms and an organic oxygen compound. The liquid oil used in (1) above is a petroleum fuel oil that is liquid at room temperature, such as crude oil, crude oil obtained by removing only the gasoline fraction from crude oil, atmospheric residual oil, kerosene, light oil, A heavy oil, B heavy oil, C heavy oil can be used. The olefinic hydrocarbon used in (1) is suitably a hydrocarbon having 8 or more carbon atoms, preferably a carbon number of 10 or more and having a boiling point (initial distillation point) of about 150°C from the viewpoint of stability, such as decene, Undesen,
Examples include dodecenes. In addition, liquid oils containing relatively large amounts of olefinic hydrocarbons, such as those obtained by decomposition, reforming, carbonization, etc., can also be used. The amount of olefin hydrocarbon added to petroleum fuel oil is 5% by volume based on the contribution to stability of mixed coal oil.
Above, preferably 10% by volume or more is appropriate. The organic oxygen compounds used in (1) and (2) above include compounds having a carbonyl group, such as organic acids, esters, aldehydes, ketones, acid amides,
Acid imides, acid thiols, and the like are preferred, but ethers, alcohols, phenols, and the like also have second-order effects. The content of organic oxygen in the petroleum fuel oil is preferably 0.5% by weight or more in view of its contribution to the stability of the mixed coal oil. Liquid oils containing olefinic hydrocarbons used in (2) above include petroleum-based, coal-based,
Products that are cracked or modified oil sand or oil shale heavy hydrocarbon oils and contain 5% or more by volume, and in some cases 10% or more by volume of olefinic hydrocarbons with a carbon number of 8 to 15. It will be done. Additionally, oils with a high olefin content of 32% by volume can be found. Therefore, it can be used as a hydrocarbon oil for use in the present application by adding an organic oxygen compound to it. The liquid oil containing an olefinic hydrocarbon used in (3) above may be, for example, a petroleum fuel oil with an easily oxidized olefinic hydrocarbon such as 1-dodecene added, or a liquid oil containing an olefinic hydrocarbon. Examples include the various liquid oils listed in item (2) above. By partially oxidizing a liquid oil containing these olefinic hydrocarbons, it can be easily used as a hydrocarbon-based oil for use in the present application. In (4) above, as the hydrocarbon oil of the blended coal oil of the present application, crude oil obtained by carbonizing (retorting) oil siel, light oil obtained by fractionating it,
Heavy oil generally contains 20% by volume or more of olefinic hydrocarbons and 0.5 to 5.0% by weight of organic oxygen, so these can be used as they are. The exact mechanism by which olefinic hydrocarbons and organic oxygen compounds in hydrocarbon oils contribute to the stabilization of mixed coal oil is not clear, but olefinic hydrocarbons in hydrocarbon oils contribute to the stabilization of saturated hydrocarbons. Because it is more polar than hydrogen, it is selectively adsorbed on the surface of pulverized coal, and as a result, it acts to prevent agglomeration and solidification of pulverized coal particles.Furthermore, organic oxygen compounds also have hydrophilic groups and are polar. It is assumed that it is easily adsorbed on the surface of pulverized coal particles due to hydrogen bonding, etc., and as a result, by coexisting with olefin-based hydrocarbons, a synergistic effect is exhibited and a more stable mixed coal oil can be obtained. . Note that among organic compounds, those having a carbonyl group are considered to have a strong effect due to this adsorption. In order to further improve the stability, if necessary, a very small amount of various mixed coal oil stabilizers may be added to the above mixed coal oil as a dispersion aid. The pulverized coal used in the present invention is composed of pulverized coal and/or petroleum coke with an average particle size of about 50 to 100μ or less, which passes 80% or more through a 100-mesh Tyler sieve, which is normally used in large boilers. . Generally, elemental analysis of hydrocarbon oil involves measuring the carbon and hydrogen content using a dry combustion method, etc.
Measure the sulfur content, nitrogen content, ash content, etc. using various types of equipment analysis, add up each value, and calculate the total amount.
The remaining value subtracted from 100 is the oxygen content. However, this method has a relatively large error;
It is difficult to accurately quantitatively analyze the small amount of oxygen compounds used in the present invention. Therefore, the present inventors created a calibration curve regarding absorption intensity and concentration for each absorption band using an infrared absorption spectrum, and attempted quantitative determination. For example, the absorption spectrum for organic oxygen is
There are OH groups of 3200 to 3600 cm ^-1 and carbonyl groups of ketones, aldehydes, carboxylic acids, amides, imides, thiols, etc. of 1630 to 1750 cm ^-1 , and these can be used. To 100 parts by volume of the hydrocarbon oil obtained in (1), (2), (3) and (4) above, 2 to 100 parts by volume of water is added, optionally in the presence of an emulsifier, to emulsify it. Emulsified mixed coal oil, which can be obtained by dispersing pulverized coal in water, is characterized by a low content of nitrogen oxides in the exhaust gas, and is prized for its prevention of pollution, but the amount of water used is 2 parts by volume. If the amount is less, there is no advantage of low nitrogen oxide production, and if more than 100 parts by volume of water is used, there is a problem with the emulsion stability of the hydrocarbon oil and it cannot be used. Furthermore, if an emulsifier is used when producing an emulsified oil by mixing water with a hydrocarbon oil, a more stable emulsified oil can be obtained and the stability of the emulsified mixed carbon oil can be improved. In the above, both synthetic and natural surfactants can be used as emulsifiers, and may also contain antifreeze agents, rust preventives, antifungal agents, and the like. The present invention will be explained below with reference to examples, but these examples are not intended to limit the present invention. In the following examples, pulverized coal shown in Table 1, petroleum fuel oil shown in Table 2, and sierre oil shown in Table 3 were used.

【table】

【table】

[Table] is removed.

【table】

[Table] Example 1 A hydrocarbon oil prepared by mixing 100 g of pulverized lignite that passed 95.0% by weight of Tyler's 100 mesh sieve with 94 parts by volume of heavy oil A and 6 parts by volume of 1-dodecene as an olefinic hydrocarbon was heated at a reaction temperature of 100%. 6 hours at ℃
Add 6 ml of 1-dodecene to 94 ml of liquid-phase oxidation and add 100 ml to a 300 c.c. beaker and stir and mix for about 10 minutes using a stirrer equipped with a screw-type rotor to obtain mixed coal oil A. Ta. On the other hand, for comparison, mixed coal oil B was obtained by stirring and mixing 100 ml of liquid-phase oxidized oil in the same manner as described above, with a hydrocarbon oil obtained by mixing 100 g of the fine powder lignite and 94 parts by volume of heavy oil A and 6 parts by volume of 1-dodecene. Ta. In addition, 100 ml was prepared by adding 3 ml of 1-dodecene to 97 ml of a hydrocarbon oil obtained by mixing 100 g of the fine brown coal, 97 parts by volume of heavy oil A, and 3 parts by volume of 1-dodecene in the liquid phase in the same manner as above. Mixed coal oil C was obtained by stirring and mixing. In addition, 94 ml of A heavy oil, 1
-6 ml of dodecene were stirred and mixed in the same manner as above to obtain mixed coal oil D. Furthermore, add 100 ml of heavy oil A to 100 g of the fine powder lignite.
Mixed coal oil E was obtained by stirring and mixing in the same manner as above. In each of the examples shown below, the degree of coal settling was measured by the maximum resistance force expressed in g when a steel ball with a diameter of 10 mm penetrates the mixed coal oil at a speed of 60 mm/min. If this value is large, it indicates that the pulverized coal in the mixed coal oil settles densely and cannot be put to practical use. Table 4 shows the properties of the obtained mixed coal oil after being left at room temperature for 3 and 5 weeks. Example 2 A hydrocarbon oil prepared by mixing 100 g of finely powdered bituminous coal that passed through a Tyler 100 mesh sieve at 83.8% by weight, 85 parts by volume of extraction oil, and 15 parts by volume of 1-dodecene as an olefinic hydrocarbon oil was brought to a reaction temperature of 100°C. Add 15 ml of 1-dodecene to 85 ml of the liquid-phase oxidized product for 6 hours, then add 100 ml to a 300 c.c. beaker.
The mixture was stirred and mixed for about 10 minutes using a stirrer equipped with a screw type rotor to obtain mixed coal oil F. In addition, to 100g of the above-mentioned fine powder bituminous coal, 79ml of extraction oil was added.
6 ml of oxidized #10 extract oil obtained by oxidizing #10 extract oil by-produced from a lubricating oil solvent refining device (furfural method) at an oil refinery under ultraviolet irradiation, and 15 ml of 1-dodecene.
Mixed coal oil G was obtained by stirring and mixing in the same manner as above. On the other hand, for comparison, 100 g of the fine powdered bituminous coal was added with 92 ml of oil and 8 ml of the oxidized #10 extract oil.
A mixed coal oil H was obtained by stirring and mixing in the same manner as above. Furthermore, to 100 g of the above-mentioned fine powder bituminous coal, add 90 g of extracted oil.
ml and 10 ml of 1-dodecene were stirred and mixed in the same manner as above to obtain mixed coal oil I. Furthermore, mixed coal oil J was obtained by stirring and mixing 100 g of the above-mentioned pulverized lignite with 100 ml of pulverized oil in the same manner as above. Table 5 shows the properties of the obtained mixed coal oil after being left at room temperature for 3 and 5 weeks. Example 3 The boiling point obtained by distilling 100 g of pulverized lignite that passed 95.0% by weight through Tyler's 100 mesh sieve, heavy cracked oil obtained by cracking asphalt as heavy oil A and olefinic hydrocarbons is approximately 92 ml of mixed oil prepared by mixing a fraction containing a large amount of olefinic hydrocarbons with a temperature of 150°C or higher so that the olefin content of the mixed oil is 15% by volume, and a lubricating oil solvent refining equipment at an oil refinery ( Put 8 ml of oxidized #10 extract oil obtained by oxidizing the #10 extract oil produced by the furfural method under ultraviolet irradiation into a 300 c.c. beaker.
The mixture was stirred and mixed for about 10 minutes using a stirrer equipped with a screw type rotor to obtain mixed coal oil K. Further, 100 g of the finely powdered lignite was mixed with 100 ml of the mixed oil prepared in the same manner as above, with stirring in the same manner as above to obtain mixed coal oil L. The properties of the obtained mixed coal oil after standing at room temperature for 3 weeks and 5 weeks are shown in Table 6 together with comparative examples. Example 4 100 g of finely powdered lignite that passed 95.0% by weight through a Tyler 100 mesh sieve, 100 ml of sier oil (crude oil)
and mixed in a 300 c.c. beaker for about 10 minutes using a stirrer equipped with a screw-type rotor to make mixed coal oil M.
I got it. On the other hand, for comparison, mixed coal oil N was obtained by stirring and mixing 100 g of the fine powdered lignite and 100 ml of hydrogenated sier oil in the same manner as above. Table 7 shows the properties of the obtained mixed coal oil after being left at room temperature for 3 weeks and 5 weeks. As is clear from Tables 4 to 7, the blended coal oil of the present invention has greater stability in that it does not solidify after standing for a long period of time, compared to the comparative example that uses a liquid oil that does not coexist with olefinic hydrocarbons and organic oxidation. It can be seen that this is an extremely excellent product. Example 5 100 g of fine-grained delayed coke passed through a Tyler 100 mesh sieve at 95.0% by weight, 85 parts by volume of pulverized oil, 1- as olefinic hydrocarbon oil.
85 ml of a hydrocarbon oil mixed with 15 parts by volume of dodecene was subjected to liquid phase oxidation at a reaction temperature of 100°C for 6 hours, and 100 ml of 15 ml of 1-dodecene was added to 300 c.c.
The mixture was placed in a beaker and stirred and mixed for about 10 minutes using a stirrer attached to a screw type rotor to obtain mixed coal oil O. In addition, 50 g of the finely powdered delayed coke, 50 g of finely powdered lignite that passed through a Tyler 100 mesh sieve at 95.0% by weight, 85 parts by volume of extraction oil, and 15 parts by volume of 1-dodecene as an olefinic hydrocarbon oil were mixed and carbonized. 85ml of hydrogen oil subjected to liquid phase oxidation at a reaction temperature of 100℃ for 6 hours, and 1-dodecene.
100 ml of the added 15 ml was placed in a 300 c.c. beaker and stirred and mixed for about 10 minutes using a stirrer equipped with a screw type rotor to obtain mixed coal oil p. In addition, to 100 g of the finely powdered delayed coke,
Mixed coal oil Q was obtained by stirring and mixing 100 ml of extracted oil in the same manner as described above. Further, mixed coal oil R was obtained by stirring and mixing 50 g of the finely powdered delayed coke and 50 g of the finely powdered lignite with 100 ml of head oil in the same manner as described above. Table 8 shows the properties of the obtained mixed coal oil after being left at room temperature for 3 and 5 weeks. Example 6 A hydrocarbon oil prepared by mixing 85 parts by volume of head oil and 15 parts by volume of 1-dodecene as an olefinic hydrocarbon oil was subjected to liquid phase oxidation at a reaction temperature of 100°C for 6 hours55
ml, 1-dodecene 15ml, and water 30ml.
The mixture was placed in a CC beaker and stirred and mixed for about 10 minutes using a stirrer equipped with a screw type rotor to obtain an emulsion oil. Additionally, Tyler's 100 mesh sieve is 83.8
Mixed 100 g of fine powdered blue coal that has passed the weight percent and 100 ml of the emulsion oil is stirred and mixed for about 10 minutes using a stirrer equipped with a screw type rotor to obtain mixed coal oil S.
I got it. On the other hand, for comparison, 100 g of the above-mentioned finely powdered green coal was stirred and mixed with 100 ml of oil in the same manner as described above to obtain mixed coal oil J (see Example 2). Table 9 shows the properties after standing at room temperature. Example 7 Mixed coal oil with the composition shown in Table 10 was heated in a furnace with a volume of approximately 20 m ³
Combustion was carried out using a rotary burner in a horizontal cylindrical furnace with heat-resistant material insulation, and the concentration of nitrogen oxides in the exhaust gas was measured. As is clear from Table 10, it is clear that the mixed coal oil containing water has a remarkable effect of reducing nitrogen oxides in exhaust gas compared to the mixed coal oil of the comparative example.

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

Claims (1)

[Scope of Claims] 1. 5 to 5 olefinic hydrocarbons having 8 to 15 carbon atoms
1. A mixed coal oil comprising pulverized coal dispersed in a hydrocarbon oil containing 32% by volume and 0.5 to 5.0% by weight of organic oxygen. 2. The mixed coal oil according to claim 1, wherein the hydrocarbon oil is obtained by adding a predetermined amount of the olefinic hydrocarbon and the organic oxygen to petroleum fuel oil. 3. The mixed coal oil according to claim 1, wherein the hydrocarbon oil is obtained from oil siel.