JP2019073601A - Production method for water-added fuel and combustion device - Google Patents

Abstract

To provide an efficient and stable production method for water-added fuel, and the water-added fuel that is easy to use.SOLUTION: The production method for the water-added fuel comprising mixing a fuel source, water and a surfactant to produce the water-added fuel comprises adding a surfactant selected by a following selection method of the surfactant for the water-added fuel, as the surfactant. A selection method of the surfactant has a HSP calculation step of calculating a Hansen solubility parameter of the fuel source, and a surfactant selection step of selecting the surfactant based on the Hansen solubility parameter of the fuel source calculated in the HSP calculation step, and the surfactant having a closer distance between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is preferentially selected in the surfactant selection step.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a water-mixed fuel obtained by adding water to a fuel source such as fuel oil and coal, and a combustion apparatus for burning the same.

Hydrolyzed fuel is effective for reducing fuel consumption and reducing CO ₂ emissions, and various proposals have been made, for example, as in Patent Documents 1 and 2 below.

  The water-mixed fuel of Patent Document 1 is a mixture of fuel oil, water and an emulsifier, and the water-mixed fuel of Patent Document 2 is a mixture of coal powder, water and a surfactant, and all of them are in a predetermined mode. By adding a surfactant (emulsifier), it is possible to obtain a hydrolyzed fuel in a good mixed state without oil and water separation.

  However, the choice of surfactant for producing a hydrous fuel has been made experimentally or empirically from among a large number of surfactants. The determination of the amount of surfactant added was similar. In other words, there is a possibility that relative evaluation can not be made regarding mixing of different types of fuel sources and various surfactants, and it is possible not to select the optimum surfactant, and use more surfactant than necessary. There was also a possibility of doing.

  In addition, due to difficulties in stable dispersion of the water-added fuel over a long period of time, as shown in FIG. 9, the fuel tank 103 for storing the heavy oil 102 and the water are stored in the water-fuel combustion device 101 so far. A water tank 105 for storing 104, a supply pipe 106 extending from the fuel tank 103, and a supply pipe 107 extending from the water tank 105, and the ends of the supply pipes 106 and 107 are joined and connected to the burner 108. In the first stage of the above, it was necessary to stir through the mixer 109 without fail. In FIG. 3, 110 is a blower for air supply, and 111 is a boiler.

JP, 2015-147842, A Japanese Patent Application Laid-Open No. 61-204296

  The present invention has as its main object to make it easy to use a water-mixed fuel, as well as to efficiently and stably manufacture the water-filled fuel.

  In order to solve the above-mentioned subject, based on the Hansen solubility parameter of the fuel source computed by the HSP calculation process of computing the Hansen solubility parameter of the fuel source mixed with water, and the HSP calculation process, the water and the A surfactant selection step of selecting a surfactant to be added upon mixing with a fuel source, wherein, in the surfactant selection step, a Hansen solubility parameter of the fuel source and a Hansen solubility of hydrophobic groups of the surfactant The method of surfactant selection for water-mixed fuel was adopted in which the one with a closer distance to the parameter is preferentially selected.

  The surfactant selected in the surfactant selection step is not only a single surfactant, but also a mixture of a plurality of surfactants to adjust or adjust the Hansen solubility parameter of the hydrophobic group, It is also good.

  In this configuration, a surfactant suitable for dispersing the fuel source in water is numerically selected based on the Hansen solubility parameter of the fuel source.

  According to the present invention, the selection of a suitable surfactant is carried out using the Hansen solubility parameter of the fuel source to design the hydrolyzing fuel, so that the production of the hydrolyzing fuel whose dispersion state is maintained for a long time is efficiently and stably Will be able to For this reason, the amount of surfactant used can be reduced, and it is also possible to use as a fuel source, for example, lignite which is low in quality as fuel and can only be discarded as fuel. , Make a significant contribution to the reduction of running costs.

  In addition, since good dispersibility can be surely obtained over a long time, the hydrous fuel can be used stably even if it is stored in a tank after production, so it is easy to use. As a result, it is possible to simplify the combustion apparatus by reducing the components of the combustion device for burning the water-mixed fuel.

The schematic block diagram of a combustion apparatus. Explanatory drawing which shows the surfactant selection method of water-ized fuel. Photomicrograph showing crushed brown coal. The photograph which shows the result of the dispersibility test of brown coal. The figure which shows the melt sphere of brown coal. The photograph which shows the result of the test which confirmed dispersion stability. The photograph which shows the result of the dispersibility test of A heavy oil. The figure which shows the melt sphere of A heavy oil. The schematic block diagram of the conventional combustion apparatus.

  One embodiment for carrying out the present invention will be described below with reference to the drawings.

  In FIG. 1, the schematic block diagram of the combustion apparatus 11 using the coal water slurry as an example of a water-repellent fuel is shown. The combustion device 11 uses a coal water slurry as an auxiliary fuel. A coal water slurry is manufactured using lignite which is low in coalification and low in the degree of coalification and high in water content and impurities and therefore only low quality and discarded.

  First, a method of producing a coal water slurry as a water-mixed fuel will be described.

  Hydrolyzed fuel is manufactured by mixing a fuel source, water and surfactant. As a fuel source, desired ones can be used from fuel sources such as coal such as lignite described above, A fuel oil, B fuel oil, C fuel oil, gasoline, kerosene, light oil, vegetable oil, animal oil, waste oil and the like. In this example, although the example using the above-mentioned lignite is demonstrated, there is no difference in a manufacturing method.

  As for water, suitable water such as tap water can be used, and processing is not particularly required unless there are special circumstances such as impurities that may interfere with fuel production.

  The surfactant is selected by the following method of selecting a surfactant for a water-mixed fuel. This selection method is based on the HSP calculation step of calculating the Hansen solubility parameter of the fuel source to be mixed with water and the addition when mixing the water and the fuel source based on the Hansen solubility parameter of the fuel source calculated in the HSP calculation step. The surfactant selection step of selecting the surfactant to be selected, and in the surfactant selection step, the distance Ra between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is closer It is something which is selected preferentially (see Figure 2).

Here, the Hansen solubility parameter (hereinafter, also simply referred to as "HSP") is a parameter representing the dissolution characteristics between substances, and the amount of Berthl divided into three cohesive energy components of δ _d , δ _p , δ _h It is. δ _d is an energy due to dispersive force between molecules: a dispersive force term, δ _p is an energy due to a dipolar interaction between molecules: a force item between dipoles, and δ _h is an energy due to hydrogen bonds between molecules: It is a hydrogen bonding force term.

  Since HSP is a vector quantity as described above, it is known that there is hardly any substance which is pure and exhibits the same value. Also, HSPs of commonly used substances are databased, and HSPs of desired substances can be obtained by referring to the database. Even non-database substances can be calculated using computer software such as HSPiP (Hansen Solubility Parameters in Practice). It can be calculated even in the case of a mixture of multiple substances.

  The lignite used as a fuel source is a special rock produced from the ground, and its HSP is not known, and may differ depending on the production area. Thus, it is necessary to calculate the HSP of lignite used (HSP calculation step s11).

The method of calculating HSP of brown coal is known and is roughly as follows. First, multiple pure solvents with known HSP are selected to evaluate their affinity for coal. Next, on a three-dimensional graph whose axes are the three parameters (δ _d , δ _p , δ _h ) constituting the above-mentioned HSP, the HSP of a good solvent with good affinity and a poor solvent of poor affinity are plotted Then, a good solvent is inside, and a poor solvent is outside, create a virtual dissolving sphere with a minimum radius, and determine the center of this dissolving sphere as the HSP of lignite. The radius Ro of the dissolving sphere is the interaction radius.

  In the selection of the pure solvent described above, the balance between the poor solvent and the good solvent in three-dimensional space is considered. That is, the type and number of solvents are selected so that the poor solvent covers the soluble sphere as uniformly as possible. At this time, the fitting parameter “0” indicates whether the good solvent is contained in the soluble sphere without exception or whether the poor solvent is contained in the soluble sphere in the range of “0.000” to “1.000”. .8 "or more. The soundness is high as the fitting parameter approaches "1.000", and as described above, it has sufficient soundness if it is "0.8" or more, and the accuracy of the HSP value is secured I judge that I can do it.

In order to calculate the HSP of lignite, as shown in Table 1, a dispersion test was conducted using 14 types of solvents (No. 1 to No. 14). The HSPs (δ _d , δ _p , δ _h ) of each solvent are known as described above and are listed to the right of the solvent names in Table 1.

In the test, 30 ml of a solvent and about 0.05 g of crushed brown coal were put in a candle bottle, shaken by hand 30 times and allowed to stand, and the state after 24 hours was visually observed.

  Brown coal is from Indonesia, and atomization by grinding was performed as follows. About 5.0 g of lignite, 500 g of 2.0 mm zirconia balls and 100 ml of water were added to the pot and ball milling was carried out at 100 rpm for 24 hours. The brown coal powder could be refined to a particle size of about 3 μm or less as shown in the microphotograph of FIG. The finely divided lignite was used in the experiment after separating water and zirconia balls and drying in a drier.

  The results of the dispersibility test were given Score “1”, “2”, “3”, “0” according to the shade of color. The darker the better the dispersibility, the score “1”, and the darker the score “2”. On the other hand, those having a large amount of lignite precipitated were given Score “0”, and those having a smaller color but showing precipitation as Score “0” were given Score “3”. Therefore, “1” is a better solvent than Score “2”, and Score “3” “0” is a poor solvent.

  As shown in the photograph of FIG. 4, the results can be confirmed from Score “1” indicating a good solvent to Score “0” indicating a poor solvent. In Table 1, each solvent is arranged in order of “1”, “2”, “3”, “0” and each Score from the top.

  From the obtained results, HSPs (δd, δp, δh) of a good solvent and a poor solvent are plotted on a three-dimensional space, and the result of creating a dissolved sphere is shown in FIG.

  As shown in Table 2, δd, δp and δh are “22.6”, “10.0” and “13.6”, respectively, as shown in Table 2. It turns out that it becomes.

The melt sphere fit is “0.926”, which is also understood to have high soundness. The radius Ro of the dissolving sphere is 14.6.

  An appropriate surfactant is then selected based on the thus obtained HSP of lignite (see FIG. 2. Surfactant selection steps s12 and s13).

  That is, the distance Ra between the HSP of brown coal and the HSP of the hydrophobic group of the surfactant stored in the database 31 is calculated and compared (comparing step s12). Then, a surfactant having a closer distance Ra between the HSP of brown coal and the HSP of hydrophobic group is preferentially selected (selection step s13). Although the calculation of the distance Ra is performed by a computer, the comparison itself and the selection may be performed automatically based on a program or manually.

Specifically, as shown in Table 3, after the surfactant selection steps s12 and s13,
"Tetradecyltrimethylammonium Bromide",
"Hexadecatrimethylammonium Chloride",
"Hexadecatrimethylammonium Bromide"
Three surfactants were selected.

In the determination of the surfactant, as described above, one having a closer distance Ra is preferentially selected, but in addition to selecting a surfactant having the closest Ra, if dispersibility can be ensured, the second closest interface is possible. An activator or a third closest surfactant may be selected.

  Specifically, the distance Ra between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is 60% or less of the length of the radius Ro of the molten sphere prepared in the HSP calculation step. It is preferable to select a surfactant that is More preferably, 50% or less of the surfactant may be selected.

  The above-mentioned three selected surfactants have a distance Ra of “6.8”, “8.2”, “8” with respect to HSP of lignite having a radius Ro of the molten sphere “14.6”. In all cases, the distance Ra is 60% or less of the length of the radius Ro of the melting sphere, and the distance Ra is short.

  Whether or not the selected surfactant shows good dispersibility in the mixture of lignite and water was confirmed by the following experiment.

  In the experiment, among the three surfactants selected in the surfactant selection steps s12 and s13, "Tetradecyltrimethylammonium Bromide" having the smallest value of Ra is compared with the value of Ra larger than that for comparison, "10. A surfactant called "Trimethylsteallammonium Chloride", which is not selected, was used.

  In the experiment, the concentration of lignite powder was 0.1 g / ml, and the surfactant concentration was 0.01 w%, 0.1 w%, and 1 w%, and the mixture of lignite powder, water, and surfactant was superfluous. Dispersion treatment was carried out for 5 minutes with sound waves and allowed to stand, and the appearance after 24 hours was visually observed. The evaluation was carried out to measure the particle size in the liquid in order to evaluate whether the amount of precipitation is large or small, and the dispersion power. The particle diameter was measured using a concentrated particle size analyzer "FPAR-1000" manufactured by Otsuka Electronics Co., Ltd.

  Fig. 6 shows a photograph of the result. Table 4 summarizes the results of the visual evaluation and the particle diameter measurement in a table.

As can be seen from FIG. 6 and Table 4, in the solvents selected in the surfactant selection steps s12 and s13, the dispersibility was good at either the concentration of 1.0 w% or 0.1 w%, whereas In the surfactant of the example, the amount of precipitation was large at any concentration, and the dispersion was poor. Further, from the measurement results of the particle diameter, it can be seen that particles having a large particle diameter are also stably dispersed. The higher the concentration of the surfactant, the better the dispersibility. However, even with a small amount of 0.1 w%, good dispersibility is obtained.

  From the results of experiments to confirm such dispersibility, it is possible to use many surfactants, including those with large particle sizes, by using a surfactant in which the distance Ra between the HSP of brown coal and the HSP of the hydrophobic group of the surfactant is close. It can be seen that the particles of H. can be dispersed and the amount of precipitation can be reduced. That is, it is possible to stably impart the flowability necessary for fuel to lignite, which is a powder of rock.

  In this experiment, as the surfactant of the comparative example, the one having an Ra of “10.6” was selected, and the results as described above were obtained. However, the three solvents selected in the surfactant selection steps s12 and s13 In Table 3), it can be inferred that either the surfactant of “8.2” or the surfactant of “8.4” will perform a sufficient function.

  Therefore, in the selection in the surfactant selection steps s12 and s13, the surfactant having the smallest value of Ra does not necessarily have to be selected, and various conditions among the smaller ones based on the value of Ra, For example, the selection is made in consideration of the toxicity of the surfactant itself and the physical properties such as flammability and viscosity, the operating conditions of the combustion apparatus, and various conditions such as the required safety.

  The surfactant selected as described above is added during mixing as a surfactant of a water-mixed fuel produced by mixing the fuel source, water and surfactant. The brown coal is micronized as in the previous experiment and then mixed with water at a predetermined rate. Before or after mixing the lignite and water, a surfactant is added and mechanically or manually stirred. As manufactured in this manner, no special equipment is required for the preparation of the coal water slurry.

  The concentration of the surfactant to be added is appropriately set depending on the concentration of lignite, the particle diameter of lignite, the particle diameter distribution, etc. However, if a surfactant having a similar Ra is used as described above, the concentration of the surfactant is low. You may

  In addition, when HSP of a fuel source is known beforehand, HSP calculation process s11 can be omitted from the manufacturing method of the above-mentioned water fuel, and when it is known beforehand to surfactant which should be chosen, it is surfactant. The agent selection steps s12 and s13 can also be omitted.

  Next, the combustion device 11 will be described.

  The combustion apparatus 11 is, as shown in FIG. 1, a fuel oil which is a main fuel, in this case, for example, a main fuel tank 12 for storing A heavy oil, and a water fuel which is an auxiliary fuel Hydrophilic fuel tank 13 for storing the coal water slurry as hydrolyzate fuel manufactured in (1), burner 14 for burning, blower 15 for sending air to burner 14, fuel for connecting main fuel tank 12 and burner 14 A supply passage 16 and a water supply passage 17 for directly connecting the water fuel tank 13 and the burner 14 are provided. In FIG. 1, 18 is a boiler.

  The water-mixed fuel stored in the water-mixed fuel tank 13 uses lignite as a fuel source as described above.

  Although illustration is omitted, the combustion device 11 is provided with a control device that appropriately switches the combustion of heavy oil and the combustion of coal water slurry.

  As described above, the combustion apparatus 11 includes the main fuel tank 12 and the water-containing fuel tank 13 and connects them to the burner 14. This is because once the coal water slurry is manufactured by mixing, high dispersibility is stably maintained over a long time, and the mixer to be mixed before being supplied to the burner 14 becomes unnecessary.

  In the combustion apparatus 11 having such a configuration, the A fuel oil is stored in the main fuel tank 12, the coal water slurry manufactured by the above-described manufacturing method is stored in the hydrous fuel tank 13, and the burner 14 is ignited to perform predetermined operation I do.

  According to the method of selecting a surfactant for hydrolyzing fuel as described above and the method for producing a hydrolyzing fuel using the same, unlike the prior art in which the dispersiveness is blindly selected from many surfactants, the fuel source is different. The choice of surfactant suitable for dispersing in water can be done numerically based on Hansen solubility parameters such as lignite as fuel source. The Hansen solubility parameter represents the dissolution characteristics between substances, and the solubility can be determined objectively. For this reason, it is possible to efficiently and stably manufacture the water-mixed fuel in which the dispersed state is maintained for a long time. In other words, it is possible to reliably obtain a fluid stable hydrolyzed fuel.

  Moreover, since the fitting parameter of the melt sphere prepared in the HSP calculation step is 0.8 or more, the melt sphere is high in soundness, and high certainty in selection can be obtained.

  In the surfactant selection steps s12 and s13, the distance Ra between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is 60 of the length Ro of the radius Ro of the molten sphere prepared in the HSP calculation step. Also by selecting a surfactant having a length of% or less, the proximity of the distance Ra can be secured, and high certainty of selection can be obtained.

  In addition, since an appropriate surfactant can be selected, good dispersibility can be obtained even if the amount of surfactant used is small, so that the cost can also be reduced.

  In addition, since it is only necessary to mix water and a selected surfactant with a fuel source such as lignite, it is not necessary to manufacture special equipment, and it can be easily manufactured. Both small and large quantities can likewise be easily produced.

  And since the hydrous fuel manufactured once has high dispersibility and maintains a dispersed state over a medium time, it can be stored in the hydrous fuel tank 13 of the combustion apparatus 11 and supplied as it is as fuel. Therefore, the configuration of the combustion device 11 can be simplified, and the size can be reduced.

In particular, using a coal water slurry using lignite as a fuel source as an auxiliary fuel for the combustion apparatus 11 is not only effective in reducing the fuel used or reducing CO ₂ emissions, but as described above, the amount of surfactant used The cost can be reduced because the combustion apparatus 11 is also simple and the cost can be reduced. In addition, effective use of lignite, which has almost no value as coal, can be achieved.

  Such a water-mixed fuel and a combustion apparatus 11 using the same can be particularly effectively used as a small-scale heating facility such as a greenhouse of a small-scale farmhouse, for example.

  The water-mixed fuel may be designed not only as an auxiliary fuel as in the above-described combustion device 11 but also usable alone for combustion.

  In this case, for example, A heavy oil may be used as a fuel source.

  For reference, HSP was also calculated for A fuel oil. HSP calculation process s11 and surfactant selection processes s12 and s13 are the same as that of the above-mentioned which illustrated brown coal.

In order to calculate HSP of A heavy oil, as shown in Table 5, the dispersibility test was done using 17 types of solvents (No. 1 to No. 17). The HSPs (δ _d , δ _p , δ _h ) of each solvent are known as described above and are listed to the right of the solvent names in Table 5.

In the test, 1 ml of the solvent and 1 ml of heavy oil A were placed in a screw tube, shaken by hand 20 times, allowed to stand, and visually observed for 24 hours.

  The photograph of the result is as showing in FIG. 7, and what was compatible with the solvent, Score "0" was attached | subjected to what was separate "Score" "1", and what was isolate | separated into 2 phases (refer Table 5).

From the obtained results, HSPs (δ _d , δ _p , δ _h ) of a good solvent and a poor solvent are plotted on a three-dimensional space, and the result of creating a soluble sphere is shown in FIG.

As shown in Table 6, δ _d , δ _p and δ _h are “20.2”, “0.1” and “12. It turns out that it will be 5 ".

The melting sphere fit is "0.863", which is also understood to have high soundness. The radius Ro of the dissolving sphere is 14.1.

  Thereafter, based on the HSP of the brown coal thus obtained, selection of an appropriate surfactant is performed (surfactant selection steps s12 and s13). The description of this process is omitted because the selected surfactant is the same as the above-described example except that it is the same.

11 ... combustion device 12 ... main fuel tank 13 ... hydrous fuel tank 14 ... burner 16 ... fuel supply path 17 ... hydrous fuel supply path

Claims (8)

An HSP calculation step of calculating a Hansen solubility parameter of a fuel source mixed with water;
A surfactant selection step of selecting a surfactant to be added upon mixing of the water and the fuel source based on the Hansen solubility parameter of the fuel source calculated in the HSP calculation step;
The surfactant selection method for a water-containing fuel, wherein in the surfactant selection step, the distance between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is preferentially selected. The method for selecting a surfactant according to claim 1, wherein the fitting parameter of the melt sphere prepared in the HSP calculation step is 0.8 or more. In the surfactant selection step, the distance between the Hansen solubility parameter of the fuel source and the Hansen solubility parameter of the hydrophobic group of the surfactant is 60% of the length of the radius of the dissolved sphere prepared in the HSP calculation step. The method for selecting a surfactant according to claim 1 or 2, wherein the surfactant having the following length is selected. The method according to any one of claims 1 to 3, wherein the fuel source is brown coal. The method according to any one of claims 1 to 3, wherein the fuel source is heavy oil A. A method of producing a water-mixed fuel produced by mixing a fuel source, water and a surfactant, comprising:
A method for producing a water-mixed fuel, wherein a surfactant selected by the method for selecting a water-soluble fuel according to claim 1 or 2 is added as the surfactant. A water-mixed fuel tank for storing water-mixed fuel manufactured by the method of manufacturing water-mixed fuel according to claim 6;
A burner for burning,
A combustion apparatus comprising a water supply passage connecting the water tank and the burner directly. A main fuel tank for storing fuel oil,
A fuel supply passage connecting the main fuel tank and the burner;
The combustion apparatus according to claim 7, wherein the water-mixed fuel stored in the water-mixed fuel tank uses lignite as the fuel source.