A method for measuring the density of Fischer-Tropsch wax made from high melting point coal

Abstract

The present invention relates to a method for measuring the density of high-melting-point coal-made Fischer-Tropsch wax, comprising the following steps: S1, washing a density bottle and weighing m0; S2, filling the density bottle with water and weighing m1; S3, pouring out the water in the density bottle, heating a solid coal-made Fischer-Tropsch wax sample until it is completely melted and then injecting it into the density bottle, driving away bubbles, and then gradually cooling it to solidification at room temperature, so that the coal-made Fischer-Tropsch wax is flush with the bottle mouth of the density bottle after solidification; S4, weighing the density bottle containing the solid coal-made Fischer-Tropsch wax m2; the density of the coal-made Fischer-Tropsch wax sample is calculated to be wherein ρ0 is the density of water. The present invention allows the high-melting-point Fischer-Tropsch wax to stably solidify from a high-temperature liquid state to a solid state, eliminating the volume influence of bubbles and the like, thereby accurately measuring the density value.

Description

Technical Field

[0001] This invention relates to the technical field of coal-to-oil product testing, specifically to a method for determining the density of Fischer-Tropsch wax made from high-melting-point coal. Background Art

[0002] Currently, there are no relevant reference standards for density determination of petrochemical industry product waxes. Conventional methods for determining the density of petroleum products include the hydrometer method, the density bottle method, and the U-tube method. The melting point of most petrochemical industry product waxes is between 40℃ and 60℃. While there is some error when using a hydrometer at around 60℃, it is still within a safe and controllable range. The melting point of high-melting-point coal-based Fischer-Tropsch wax (70℃-90℃) is higher than that of petroleum-based wax (40-60℃), and its complete melting temperature can reach over 120℃. When using the conventional hydrometer method to determine the density of liquid coal-based Fischer-Tropsch wax, the deviation is large at high temperatures, which may even cause the hydrometer to explode, resulting in a safety accident. Using the U-tube method to determine the density of liquid coal-based Fischer-Tropsch wax can clog the instrument; U-tube instruments are generally used for measuring room-temperature liquids and do not have a high-temperature measurement mode. High-temperature liquid samples will solidify and clog the instrument after injection. When determining the solid density using the density bottle method, sample preparation is difficult, as air bubbles often exist inside the solid wax, causing inaccurate volume measurements. When cutting a portion using the cutting method, the high hardness can cause some areas to be compressed, altering the density. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for determining the density of Fischer-Tropsch wax made from high-melting-point coal, which addresses the shortcomings of the prior art.

[0004] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A method for determining the density of Fischer-Tropsch wax made from high-melting-point coal, comprising the following steps:

[0005] S1. Wash the density bottle and weigh it m0.

[0006] S2, fill the density bottle with water and weigh it m1;

[0007] S3. Pour out the water from the density bottle, heat the solid coal Fischer-Tropsch wax sample until it is completely melted and pour it into the density bottle, remove the air bubbles, and then place it at room temperature to cool gradually until it solidifies, so that the solidified coal Fischer-Tropsch wax is flush with the mouth of the density bottle.

[0008] S4, Weigh the density bottle containing solid coal-derived Fischer wax (m2);

[0009] The density of the coal-derived Fischer-Tropsch wax sample was calculated to be: Where ρ0 is the density of water.

[0010] The beneficial effects of this invention are: by enabling high-melting-point Fischer-Tropsch wax to stably solidify from a high-temperature liquid state to a solid state, this invention eliminates the volume influence of bubbles and other factors, thereby accurately determining the density value.

[0011] Based on the above technical solution, the present invention can be further improved as follows.

[0012] Further, in S3, the solid coal-based Fischer-Tropsch wax sample is heated until completely melted and then injected into a density bottle. The bottle is then placed in an ultrasonic water bath at 80-95℃ and sonicated for 3-10 minutes to remove air bubbles from the melted coal-based Fischer-Tropsch wax.

[0013] The advantages of adopting the above-mentioned further scheme are: after the wax sample is melted uniformly at high temperature, it is injected into a density bottle, the air bubbles are removed in an ultrasonic environment and it is gradually cooled to a solid state, and then the density is calculated after weighing. This method is convenient, safe and accurate.

[0014] Furthermore, the temperature of the ultrasonic water bath is 90°C, and the ultrasonic time is 5 minutes.

[0015] The beneficial effect of adopting the above-mentioned further solution is that by reasonably setting the temperature and time of the ultrasonic water bath, it is possible to ensure that the Fischer-Tropsch wax remains in a liquid state while expelling air bubbles and other particles.

[0016] Furthermore, in S3, after the coal-derived Fischer-Tropsch wax in the density bottle is gradually cooled to room temperature and solidified, an appropriate amount of liquid wax sample is added to compensate for the shrinkage caused by the solidification of the wax sample, until the solidified wax sample is exactly flush with the mouth of the density bottle.

[0017] The beneficial effect of adopting the above-mentioned further solution is that by using the wax replenishment method, the volume of the wax sample in the density bottle can be made consistent with the volume of the density bottle, thus ensuring the accuracy of the measurement data.

[0018] Furthermore, in S3, the solid coal-derived Fischer-Tropsch wax sample is heated to 110-130°C until completely melted and then injected into a density bottle.

[0019] Furthermore, in S2, the density bottle filled with water is immersed in a constant temperature water bath, kept at a constant temperature for more than 30 minutes, then removed, the outer wall is wiped dry, and the weight m1 is weighed immediately.

[0020] The advantage of adopting the above-mentioned further scheme is that it ensures that the density bottle filled with water is under the same conditions as the subsequent experiments, thus guaranteeing the accuracy of the measurement data.

[0021] Furthermore, in S4, the density bottle containing solid coal-derived Fischer-Tropsch wax is immediately immersed in a constant temperature water bath at 20℃±0.1℃, kept at the constant temperature for more than 30 minutes, removed, and its outer wall is wiped dry before being weighed immediately (m2).

[0022] The beneficial effect of adopting the above-mentioned further solution is that it ensures the accuracy of the measurement data by placing the density bottle filled with Fischer-Tropsch wax and the density bottle filled with water under the same conditions.

[0023] Further, in S1, the density bottle is washed, dried, and weighed m0.

[0024] Furthermore, in S3, after pouring out the water from the density bottle, it is washed and dried. Detailed Implementation

[0025] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0026] Example 1

[0027] This embodiment of a method for determining the density of Fischer-Tropsch wax made from high-melting-point coal includes the following steps:

[0028] S1. Wash the density bottle, dry it, and weigh it m0.

[0029] S2, fill the density bottle with water, immerse the water-filled density bottle in a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, take it out, wipe the outer wall dry, and weigh it immediately m1.

[0030] S3. Pour out the water from the density bottle, wash and dry it; heat the solid coal Fischer-Tropsch wax sample to 110°C until it is completely melted, then pour it into the density bottle and place it in an 80°C ultrasonic water bath. Sonicate for 10 minutes to remove air bubbles from the melted coal Fischer-Tropsch wax, then allow it to cool gradually at room temperature until it solidifies; after the coal Fischer-Tropsch wax in the density bottle has been allowed to cool gradually at room temperature until it solidifies, add an appropriate amount of liquid wax sample to compensate for the shrinkage caused by the solidification of the wax sample, until the solidified wax sample is flush with the mouth of the density bottle.

[0031] S4. Immediately immerse the density bottle containing solid coal-derived Fischer-Tropsch wax into a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, remove it, wipe the outer wall dry, and weigh it immediately (m2).

[0032] In this embodiment, an analytical balance is used for weighing. The scale division of the analytical balance is not less than 0.0001g, and a 25cm density bottle can be selected. 3 The thermometer can be selected with a scale division of 0.1℃.

[0033] The density of the coal-derived Fischer-Tropsch wax sample was calculated to be:

[0034] Where m0 is the mass of the density bottle, expressed in grams (g).

[0035] m1----The mass of the density bottle when it is full of water, in grams (g);

[0036] m2----The mass of the density bottle when it is filled with the sample, in grams (g);

[0037] ρ0----The density of water at 20℃, expressed in grams per cubic centimeter (g / cm³). 3 The value is 0.9982.

[0038] Example 2

[0039] This embodiment of a method for determining the density of Fischer-Tropsch wax made from high-melting-point coal includes the following steps:

[0040] S1. Wash the density bottle, dry it, and weigh it m0.

[0041] S2, fill the density bottle with water, immerse the water-filled density bottle in a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, take it out, wipe the outer wall dry, and weigh it immediately m1.

[0042] S3. Pour out the water from the density bottle, wash and dry it; heat the solid coal Fischer-Tropsch wax sample to 120°C until it is completely melted, then pour it into the density bottle and place it in a 90°C ultrasonic water bath. Sonicate for 5 minutes to remove air bubbles from the melted coal Fischer-Tropsch wax, then allow it to cool gradually at room temperature until it solidifies; after the coal Fischer-Tropsch wax in the density bottle has been allowed to cool gradually at room temperature until it solidifies, add an appropriate amount of liquid wax sample to compensate for the shrinkage caused by the solidification of the wax sample, until the solidified wax sample is flush with the mouth of the density bottle.

[0043] S4. Immediately immerse the density bottle containing solid coal-derived Fischer-Tropsch wax into a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, remove it, wipe the outer wall dry, and weigh it immediately (m2).

[0044] In this embodiment, an analytical balance is used for weighing. The scale division of the analytical balance is not less than 0.0001g, and a 25cm density bottle can be selected. 3 The thermometer can be selected with a scale division of 0.1℃.

[0045] The density of the coal-derived Fischer-Tropsch wax sample was calculated to be:

[0046] Where m0 is the mass of the density bottle, expressed in grams (g).

[0047] m1----The mass of the density bottle when it is full of water, in grams (g);

[0048] m2----The mass of the density bottle when it is filled with the sample, in grams (g);

[0049] ρ0----The density of water at 20℃, expressed in grams per cubic centimeter (g / cm³).3 The value is 0.9982.

[0050] Example 3

[0051] This embodiment of a method for determining the density of Fischer-Tropsch wax made from high-melting-point coal includes the following steps:

[0052] S1. Wash the density bottle, dry it, and weigh it m0.

[0053] S2, fill the density bottle with water, immerse the water-filled density bottle in a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, take it out, wipe the outer wall dry, and weigh it immediately m1.

[0054] S3. Pour out the water from the density bottle, wash and dry it; heat the solid coal Fischer-Tropsch wax sample to 130°C until completely melted, then pour it into the density bottle and place it in a 95°C ultrasonic water bath. Sonicate for 3 minutes to remove air bubbles from the melted coal Fischer-Tropsch wax, then allow it to cool gradually at room temperature until it solidifies; after the coal Fischer-Tropsch wax in the density bottle has been allowed to cool gradually at room temperature until it solidifies, add an appropriate amount of liquid wax sample to compensate for the shrinkage caused by the solidification of the wax sample, until the solidified wax sample is flush with the mouth of the density bottle.

[0055] S4. Immediately immerse the density bottle containing solid coal-derived Fischer-Tropsch wax into a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, remove it, wipe the outer wall dry, and weigh it immediately (m2).

[0056] In this embodiment, an analytical balance is used for weighing. The scale division of the analytical balance is not less than 0.0001g, and a 25cm density bottle can be selected. 3 The thermometer can be selected with a scale division of 0.1℃.

[0057] The density of the coal-derived Fischer-Tropsch wax sample was calculated to be:

[0058] Where m0 is the mass of the density bottle, expressed in grams (g).

[0059] m1----The mass of the density bottle when it is full of water, in grams (g);

[0060] m2----The mass of the density bottle when it is filled with the sample, in grams (g);

[0061] ρ0----The density of water at 20℃, expressed in grams per cubic centimeter (g / cm³). 3 The value is 0.9982. Detailed Implementation

[0063] The experiment was conducted using the specific parameters of Example 2:

[0064] S1. Wash the density bottle, dry it, and weigh it (m0, 9.4363g).

[0065] S2. Fill the density bottle with freshly boiled and cooled water to room temperature, ensuring no air bubbles are introduced. Immediately after filling, immerse it in a constant temperature water bath at 20℃±0.1℃ for at least 30 minutes. Remove the bottle, wipe the outer wall dry, and immediately weigh it (m1, 35.1978g).

[0066] S3. Pour out the water from the density bottle, wash and dry it.

[0067] S4. Heat the solid wax sample to about 120℃ until it is completely melted, then pour it into a density bottle. Place the bottle in a 90℃ ultrasonic water bath and sonicate for 5 minutes to remove any air bubbles formed in the wax. Remove the bottle and allow it to cool gradually at room temperature until it solidifies. Add a suitable amount of liquid wax sample to compensate for the shrinkage caused by the solidification of the wax sample, until the solidified wax is flush with the mouth of the density bottle.

[0068] S5, after the sample is assembled, immediately immerse it in a constant temperature water bath at 20℃±0.1℃, keep it at the constant temperature for more than 30 minutes, take it out, wipe the outer wall dry, and immediately weigh it m2 (33.2132g).

[0069] The density of the tested sample is ρ, expressed in grams per cubic centimeter (g / cm³). 3 ) indicates that it is calculated using the following formula:

[0070]

[0071] In the formula:

[0072] m0----The numerical value of the mass of the density bottle, in grams (g);

[0073] m1----The mass of the density bottle when it is full of water, in grams (g);

[0074] m2----The mass of the density bottle when it is filled with the sample, in grams (g);

[0075] ρ0----The density of water at 20℃, expressed in grams per cubic centimeter (g / cm³). 3 The value is 0.9982.

[0076] That is, the density of the wax sample at 20℃ is 0.9213 g / cm³. 3 .

[0077] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0078] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for determining the density of Fischer-Tropsch wax made from high melting point coal, characterized in that: The following steps are involved: S1, wash the density bottle, dry it and weigh it m0; S2, fill the density bottle with water, immerse the density bottle filled with water in a constant temperature water bath, keep the temperature constant for more than 30 minutes, take it out, wipe the outer wall dry and weigh m1 immediately; S3, pour out the water in the density bottle, wash it and dry it; heat the solid coal-based Fischer-Tropsch wax sample to 110-130°C until it is completely melted, inject it into the density bottle, put it in a 90°C ultrasonic water bath, and ultrasonicate for 5 minutes to drive away the bubbles in the melted coal-based Fischer-Tropsch wax; the coal-based Fischer-Tropsch wax in the density bottle is placed at room temperature and gradually cooled to solidification, and a proper amount of liquid wax sample is added to supplement the shrinkage caused by the wax sample solidification, until the wax sample is just flush with the mouth of the density bottle after solidification; S4, immediately immerse the density bottle containing the solid coal-based Fischer-Tropsch wax in a constant temperature water bath at 20℃±0.1℃, keep the temperature constant for more than 30 minutes, take it out, wipe the outer wall dry and immediately weigh m2; The density of the coal-based Fischer-Tropsch wax sample was calculated to be Where ρ0 is the density of water.

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