JP3011326B2 - Fuel additives and fuels - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention particularly promotes the combustion of carbonaceous solids to improve the fuel combustion efficiency,
The present invention relates to a fuel additive and a fuel that are added to a fuel in order to suppress high-temperature corrosion due to vanadium or the like in a fuel and reduce the amount of material thinning of a combustion device.

[0002]

2. Description of the Related Art Conventionally, in a combustion apparatus such as a boiler, a heating furnace, and a diesel engine, a method of adding a combustion promoter to fuel in order to maintain good combustion state and reduce soot in exhaust gas. Has been done. Examples of the combustion promoter include those obtained by adsorbing naphthenic acid or the like to fine particles of hydroxides or oxides of divalent or tetravalent metals (Japanese Patent Application Laid-Open No. 61-152794). A cerium soap having a ratio of 3 or less and using a basic oil-soluble cerium soap (JP-A-53-12907 and JP-A-61-225282), or a mixture of at least two kinds of cerium, neodymium or lanthanum soaps (JP-B 4-70358), using magnesium acetylacetonate (Japanese Unexamined Patent Publication No. 3-171)
87 has been proposed.

[0003] Further, in order to prevent corrosion due to harmful components in the combustion exhaust gas of the combustion apparatus, compounds such as magnesium, calcium, aluminum, barium, and silicon have been added to the fuel.

[0004] By the way, even if it is gaseous or liquid fuel,
Normally, during the combustion process, a carbonaceous solid called char is generated, which is the rate-determining factor of the combustion. If it remains unburned, it is discharged as soot together with the exhaust gas.
Therefore, how fast this carbonaceous solid is burned will reduce soot and thus improve combustion efficiency.

[0005] In addition, heavy fuel such as coal, petroleum coke, or heavy oil contains vanadium having a high-temperature corrosive action, and causes a wall-thinning failure of a combustion device material such as a boiler tube.

Recently, as an energy source, a solid fuel such as coal or petroleum coke, or a CWM (coal water mixture) obtained by slurrying these with water, PCWM
(Petroleum coke water mixture) Although fuels are being reviewed, even in this type of fuel, so-called char combustion, in which volatiles are removed from solids, particularly those solids, is called soot reduction and combustion. In order to improve the efficiency, there is a need for a combustion promoter which is extremely important and has a high combustion promoting effect on char. In addition, these fuels contain a high concentration of vanadium in a concentrated form.
Combustion devices that burn them are exposed to severer corrosive environments than ever before, and advanced corrosion protection is required.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the combustion efficiency of fuel by increasing the effect of promoting the combustion of char.
It is an object of the present invention to provide a fuel additive that can significantly reduce soot in combustion exhaust gas and suppress high-temperature corrosion due to vanadium or the like in fuel, thereby reducing the amount of material thinning of a combustion device.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, surprisingly, a copper compound and a magnesium compound are mixed or used. Furthermore, it has been found that when a rare earth element compound is added, the effect of promoting combustion is enhanced and the effect of suppressing high-temperature corrosion is also improved as compared with the case where they are used alone.

The present invention has been made based on such findings, and one embodiment of the present invention includes a copper compound and a magnesium compound, wherein the copper compound and the magnesium compound are a metal hydroxide and a fatty acid metal salt. It is a fuel additive that enhances the combustion effect of carbonaceous solids generated in the combustion process and suppresses high-temperature corrosion due to vanadium in the fuel. To contain copper in a ratio of 0.2 to 1. Another embodiment of the present invention relates to a copper compound containing 0.001 to 0.1% by weight as a Cu metal content and 0.001 to 0.2% by weight of a magnesium compound as a Mg metal content. The fuel is characterized in that the compounds are a metal hydroxide and a fatty acid metal salt, the effect of burning carbonaceous solids generated in the combustion process is high, and high-temperature corrosion due to vanadium in the fuel is suppressed. Further, another embodiment of the present invention is characterized in that a copper compound, a rare earth element compound and a magnesium compound are mixed, and the copper compound, the rare earth element compound and the magnesium compound are a metal hydroxide and a fatty acid metal salt, Is a fuel additive that enhances the combustion effect of carbonaceous solids produced at the same time and suppresses high-temperature corrosion due to vanadium in the fuel. And a copper compound and a rare earth element compound are contained at a metal content weight ratio of 0.2 to 5 with respect to copper. Further, in another embodiment of the present invention, the copper compound is 0.001 to 0.1% by weight as a Cu metal content, the rare earth element compound is 0.001 to 0.1% by weight as a rare earth metal content, and a magnesium compound is Is 0.001 to 0.00 as a Mg metal weight.
2% by weight, the copper compound, the rare earth element compound and the magnesium compound are metal hydroxides and fatty acid metal salts. This fuel is characterized in that high-temperature corrosion is suppressed.

As the copper compound, a hydroxide or a soap with a fatty acid which can be dissolved or easily dispersed in a fuel or an organic solvent is used. In particular, copper hydroxide, copper octylate, copper neodecanoate, copper naphthenate or It is preferable to use copper tall oilate or the like.

Similar to the above, it is particularly preferable to use magnesium compounds, such as magnesium hydroxide, magnesium octylate, magnesium neodecanoate, magnesium naphthenate or magnesium tall oil.

According to the present invention, the use of a mixture of the above-mentioned copper compound and the magnesium compound significantly enhances the combustion promoting effect and the high-temperature corrosion inhibiting effect as compared with the case where they are used alone. It is essential to use a mixture of these. The mixing ratio is preferably such that copper is mixed with magnesium in a ratio of 0.2 to 1 in terms of metal weight ratio, and particularly preferably 0.3 to 0.7.

It is preferable to mix a rare earth element compound with the above copper compound and magnesium compound, because the effect of promoting combustion and the effect of suppressing high-temperature corrosion can be further enhanced.

As the rare earth element compound, for example,
Cerium, neodymium, lanthanum, praseodymium, samarium, promethium, europium, gadolinium, terbium, dysprosium, holmium, erbium,
Any of compounds such as thulium, ytterbium, and lutetium can be used, and hydroxides and fatty acids that can be dissolved or easily dispersed in a fuel or an organic solvent are used, and in particular, cerium, neodymium, and lanthanum are used as rare earth elements It is preferable to use these hydroxides, octyl acid soap, neodecanoate, naphthenate or tall oil. These rare earth elements can be used alone or as a mixture of two or more kinds. In particular, the main component is cerium,
It is particularly preferable to use a compound obtained by using a mixed rare earth or a concentrated rare earth made of a mixture of neodymium, lanthanum, etc., at a low cost.

The fuel additive of the present invention may be one obtained by simply mixing the above compounds. However, these compounds may be prepared by mixing these compounds with an organic solvent such as an aliphatic, alicyclic or aromatic hydrocarbon or a mixture thereof. , Naphtha, petroleum ether, white spirits, mineral terpen, kerosene, light oil, hexane, heptane, octane, nonane, decane, dodecane,
Tetradecane, cyclohexane, benzene, toluene,
It is preferable to dissolve or disperse in a generally used organic solvent such as xylene and ethylbenzene. In this case, the concentration of these compounds is preferably as high as possible from the viewpoint of handling.However, the solubility and the physical properties of the resulting solution or dispersion differ depending on the type of the copper compound, rare earth compound or magnesium compound. It is good to select appropriately according to each. Generally, the concentration of the total metal is 1 to 40% by weight.
It is preferable to adjust so as to fall within the range.

Other fuels of the present invention include the compounds described above, for example, petroleum hydrocarbons such as gasoline, kerosene, light oil, heavy oil, hydrocarbon fuels such as shale oil, coal liquefied oil, and petroleum. It is added to a carbonaceous fuel such as coke, coal, or a slurry of these with water.

In adding and mixing these fuels, the above-described copper compound, magnesium compound, and rare-earth element compound may be separately added and mixed, respectively. It is convenient and preferable to add it to the fuel.

In this case, the amount of these compounds to be added cannot be unconditionally determined depending on the kind of fuel, but generally, the amount of the copper compound is 0.001 and Cu is 0.001.
To 0.1% by weight, a magnesium compound in a range of 0.001 to 0.2% by weight as magnesium, and a rare earth element compound in a range of 0.001 to 0.1% by weight as a rare earth element. And adding these copper compound and magnesium compound at a metal weight ratio of 0.2 to 1 for copper to magnesium and 0.2 to 5 for a rare earth element to copper. Is preferred.

[0019]

EXAMPLES Preparation of fuel additive (1) 100 g (0.58 mol) of neodecanoic acid and kerosene 1
1300 g of 20% by weight aqueous sodium hydroxide solution in 20 g
(6.5 mol) and stirred at 80 ° C. for 30 minutes to obtain a sodium neodecanoate solution. To this were added 1190 g (2.5 mol) of a 20% by weight aqueous magnesium chloride solution and 350 g (0.52 mol) of a 20% by weight aqueous cupric chloride solution, and the mixture was stirred at 80 ° C. for 3 hours. The resulting kerosene solution of metal hydroxide and organic acid metal salt aggregated into a ball shape in the aqueous solution. This was filtered to separate and remove the aqueous solution.
After drying at 10 ° C. for 24 hours, 370 g of a kerosene solution containing a metal hydroxide and a metal salt of an organic acid was obtained. To this solution, 220 g of kerosene, 3 g of lecithin and 1 g of water were added and stirred to obtain 594 g of a kerosene solution (10 wt% as Mg, 5 wt% as Cu) in which a metal hydroxide and a metal salt of an organic acid were mixed. This was Fuel Additive A.

(2) For comparison, a kerosene solution (10% by weight as Mg) mixed with a metal hydroxide and an organic acid metal salt was prepared in the same manner as above using an aqueous solution of 20% by weight of magnesium chloride. This was used as fuel additive B.

(3) For comparison, a kerosene solution containing copper hydroxide and organic acid copper (5% by weight as Cu) was prepared in the same manner as above using a 20% by weight aqueous cupric chloride solution. ) Was obtained and used as fuel additive C.

(4) To a part of fuel additive A, a light oil solution of rare earth octylate (concentration of rare earth element: 8% by weight, weight composition ratio: cerium / neodymium / lanthanum = 2/1/1) Additive D (RE-Cu additive; 10% by weight as Mg,
5% by weight as Cu and 5% by weight as RE) were prepared.

(5) Rare earth octylate gas oil solution (rare earth element concentration 8% by weight, weight composition ratio: cerium / neodymium /
(Lanthanum = 2/1/1) was used as the fuel additive E.

High Temperature Corrosion Test 160 g of vanadium pentoxide and 40 g of anhydrous sodium sulfate were pulverized and mixed in a ball mill, and 1 g of this synthetic ash was added with the fuel additives prepared above in the amounts shown in Table 1. After mixing while crushing in a mortar, 100 ~
After drying at 110 ° C. for 3 hours, 5 ml of acetone was added and mixed to prepare a suspension. This solution is applied to a SUS-321 test piece.
Synthetic ash was applied so as to be 20 mg / cm ² (when dried), and heated at 900 ° C. for 3 hours in a muffle furnace in an air atmosphere. After descaling the heated test piece, the weight loss of the test piece was measured, and the weight loss of the test piece without the addition of the fuel additive was defined as 100, and the reduction rate was determined.
The results are shown in Table 1.

[0025]

[Table 1]

As is evident from the results, copper and rare earth elements have no effect of reducing wall thinning due to high-temperature corrosion.
It can be seen that when copper and rare earth elements are combined with magnesium, the effect of reducing wall thinning due to high-temperature corrosion is greater than when used alone.

Combustibility test of char Petroleum coke having the properties shown in Table 2 was heated at 900 ° C.
Then, by heating for 7 minutes, a carbonaceous solid having a volatile content of 0.1% by weight or less, so-called char, was used in 1 g each,
In addition, each of the above fuel additives was added in the amount shown in Table 3.
(% By weight of metal based on char) to prepare a sample, and a flammability test was performed.

[0028]

[Table 2]

In the flammability test, a quartz tube (inner diameter: 10 mm) in which nitrogen was passed at 100 ml / min was kept at a temperature of 800 ° C., and 0.1 g of the sample prepared above was put into the test tube. Hold for 5 minutes. Next, nitrogen was added to the air at 100 ml / min.
And the sample was burned. The concentration of carbon dioxide generated by combustion was measured by an infrared gas analyzer, and the burning rate was determined from the change over time of the carbon dioxide concentration by the following method. That is, when a generally used unreacted core shrinkage model is applied as a char combustion model, the CO ₂ concentration n _R generated by combustion is expressed by the following equation (1). _{n R = 3m 0 k (1} -kt) 2 / Q IN (1) , where a _{k = k 0 P 02 / αρ} 0 r 0. The symbols in the above formula are as follows. m ₀ : Total amount of generated CO ₂ [Nml] k: Combustion rate [1 / sec] t: Time [sec] Q _IN : Flowing gas quantity [Nml / sec] k ₀ : Apparent reaction rate constant [g / cm ² sec] atm] P ₀₂ : oxygen partial pressure [atm] α: ratio of carbon in the sample [−] ρ ₀ : density of the sample [g / cm ³ ] r ₀ : initial radius of the sample [cm]

From the time-dependent change in the measured CO ₂ concentration, the combustion rate was determined by the above equation (1) in consideration of the response delay of the measuring device. Note that the obtained combustion speed corresponds to the reciprocal of the combustion completion time. The results are shown in Table 3.

[0031]

[Table 3]

As is apparent from the results, the use of a combination of copper, magnesium, and the rare-earth element alone improves the combustion speed and significantly reduces the soot in the combustion exhaust gas, when used in combination. I understand.

[0033]

According to the present invention as described above, by increasing the effect of promoting the combustion of char, the combustion efficiency of the fuel can be improved and the soot in the combustion exhaust gas can be greatly reduced.
Further, the present invention has a special effect that high-temperature corrosion due to vanadium or the like in the fuel can be suppressed and the amount of reduced material in the combustion device can be reduced.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-13798 (JP, A) JP-A-3-244692 (JP, A) JP-A-6-500597 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) C10L 1/12 C10L 1/30 C10L 1/32 C10L 9/10

Claims (6)

(57) [Claims] Claims 1. A copper compound and a magnesium compound as active ingredients, wherein the copper compound and the magnesium compound are a metal hydroxide and a fatty acid metal salt. A fuel additive that suppresses high-temperature corrosion caused by vanadium in fuel. 2. The fuel additive according to claim 1, wherein the copper compound and the magnesium compound are contained at a metal content weight ratio of copper to magnesium in a ratio of 0.2 to 1. 3. A copper compound having a Cu metal content of 0.0
0.01 to 0.1% by weight and a magnesium compound in an amount of 0.001 to 0.2% by weight as a Mg metal content, wherein the copper compound and the magnesium compound are a metal hydroxide and a fatty acid metal salt. A fuel characterized by a high combustion effect of carbonaceous solids generated in the process and suppression of high-temperature corrosion due to vanadium in the fuel. 4. A carbonaceous solid produced by mixing a copper compound, a rare earth element compound and a magnesium compound, wherein the copper compound, the rare earth element compound and the magnesium compound are a metal hydroxide and a fatty acid metal salt. A fuel additive that enhances the combustion effect of fuel and suppresses high-temperature corrosion due to vanadium in the fuel. 5. The method according to claim 4, wherein the copper compound and the magnesium compound are in a metal content ratio by weight, copper is present in a ratio of 0.2 to 1 with respect to magnesium, and the copper compound and the rare earth element compound are in a metal content weight ratio. The ratio of rare earth element to copper is 0.
A fuel additive which is mixed at a ratio of 2 to 5. 6. A copper compound having a Cu metal content of 0.0
A copper compound containing 0.01 to 0.1% by weight, 0.001 to 0.1% by weight of a rare earth element compound as a rare earth metal content and 0.001 to 0.2% by weight of a magnesium compound as a Mg metal content; , Characterized by the fact that the rare earth element compound and the magnesium compound are metal hydroxides and fatty acid metal salts, the combustion effect of carbonaceous solids generated in the combustion process is high, and high-temperature corrosion by vanadium in fuel is suppressed. And fuel.