阅读说明：本技术 用于测定物质与水反应产气速率的样品混合方法 (Sample mixing method for determining gas production rate of substance reacting with water ) 是由 郭璐 王亚琴 张向倩 王康 张晨 张会光 于 2019-04-04 设计创作，主要内容包括：本发明涉及一种用于测定物质与水反应产气速率的样品混合方法,主要解决现有技术中准确度差的问题。本发明通过采用一种用于测定物质与水反应产气速率的样品混合方法,采用测定物质与水反应产气速率的试验装置进行物质与水反应产气速率测定试验,样品在测试开始前就置于试验容器内,但测试开始前不能相互混合,随着水的注入,样品与水发生混合接触并反应的技术方案较好地解决了上述问题,可用于用于测定物质与水反应产气速率的样品混合中。(The invention relates to a sample mixing method for measuring the gas production rate of a substance reacted with water, which mainly solves the problem of poor accuracy in the prior art. The invention adopts a sample mixing method for measuring the gas production rate of the reaction of a substance and water, and adopts a test device for measuring the gas production rate of the reaction of the substance and the water to carry out a gas production rate measurement test of the reaction of the substance and the water, wherein the sample is placed in a test container before the test is started, but the sample and the water cannot be mixed with each other before the test is started, and the technical scheme that the sample and the water are mixed, contacted and reacted along with the injection of the water better solves the problems, and can be used for the sample mixing for measuring the gas production rate of the reaction of the substance and the water.)

1. A sample mixing method for measuring the gas production rate of a substance reacted with water is characterized in that a test device for measuring the gas production rate of the substance reacted with water is adopted to carry out a gas production rate measurement test of the substance reacted with water, the device comprises a test container, a test container cover, a precise peristaltic pump, a sample vessel and a gas exhaust pipeline, the gas exhaust pipeline penetrates through the container cover of a top opening of the test container and extends into the test container, the other end of the gas exhaust pipeline is connected with a flow meter, the sample vessel is placed at the bottom of the test container, a recess is formed in the top of the sample vessel, the sample is placed in the recess, and; the samples were placed in the test vessel just before the start of the test but were not mixed with each other before the start of the test, and as water was injected, the samples were brought into mixing contact with the water and reacted.

2. The method according to claim 1, wherein the sample vessel is made of Teflon or glass.

3. The method according to claim 1, wherein the test container is a glass-made sealed container.

4. A sample mixing method for measuring a gas evolution rate from a substance reacting with water according to claim 1, characterized in that before the start of the test, the sample is uniformly placed on the sample dish, and then vaseline is applied to and covers the lid of the test container.

5. The sample mixing method for measuring the gas generation rate by the reaction of a substance with water according to claim 1, wherein at the beginning of the test, a precision peristaltic pump is opened, water is injected into the test container at a constant rate of 2ml/min or less, and the gas generation rate A displayed by the flow meter is the rate B of the gas discharged due to the injected water, wherein A is B; when the injected water contacts with the sample and reacts with the sample to generate gas along with the injection of the water, the flow meter displays a velocity A1, the velocity B of the discharged gas caused by the injection of the water is constant, A1 is more than B, and the difference A1-B is C, namely the velocity of the gas generated by the reaction of the sample and the water; after the water injection is finished, the gas production rate A2 displayed by the flowmeter is the rate of the gas generated by the reaction of the sample and the water.

6. A sample mixing method for determining the gassing rate of a substance on reaction with water according to claim 1 wherein the depression depth is 0.3 cm.

7. The sample mixing method for determining a gas generation rate by reaction of a substance with water according to claim 1, wherein the flow meter is a constant pressure type gas flow meter.

8. The method according to claim 1, wherein the electromagnetic valve is disposed on the outlet water line of the peristaltic pump.

9. The method according to claim 2, wherein the sample vessel is made of polytetrafluoroethylene.

10. A sample mixing method for determining the rate of gas evolution from the reaction of a substance with water according to claim 7, characterized in that the flow meter is operated in conformity with the pressure in the test bottle, and very small flow rates < 0.01ml/min can be measured.

Technical Field

The invention relates to a sample mixing method for measuring the gas production rate of a substance reacting with water.

Background

The dangers of chemicals are various, wherein, the 4.3 th category is 'wet inflammable substance', the dangers are judged by the test of 'the inflammable gas releasing speed when meeting water', the test is that the substance is fully contacted with water, the gas releasing speed is measured within more than or equal to 7 hours, and when the speed is more than 1.0L/kg.h, the substance is judged to have the wet inflammable dangers.

In the conventional test method for detecting the amount of gas released by a small flow of the released gas, a sample (usually solid powder of about 200 mesh) is usually placed in a conical flask, experimental water is placed in a container at the upper end of the conical flask, the experimental water and the conical flask are connected by a pipeline with a valve, the valve is opened during the test to enable the water to enter the conical flask, and then the rate of the gas released by the reaction of the water and a substance is measured, so that the danger is judged. In this case, the process of water entering the conical flask can have great influence on the pressure in the flask and can cause the air in the flask to flow, and the measured flow is not the flow of the gas released by the reaction of the substance and the water; the initial stage of water-to-substance contact (i.e., the stage of water entering the erlenmeyer flask and mixing with the sample) is the most vigorous and the highest gas evolution rate, and therefore, the accuracy of the data measured by the current method is not sufficient.

Disclosure of Invention

The invention aims to solve the technical problem of poor accuracy in the prior art, provides a novel sample mixing method for measuring the gas production rate of a substance reacted with water, and has the advantage of good accuracy.

In order to solve the problems, the technical scheme adopted by the invention is as follows: a sample mixing method for measuring the gas production rate of a substance reacted with water is characterized in that a test device for measuring the gas production rate of the substance reacted with water is adopted to carry out a gas production rate measurement test of the substance reacted with water, the device comprises a test container, a test container cover, a precise peristaltic pump, a sample vessel and a gas exhaust pipeline, the gas exhaust pipeline penetrates through the container cover of a top opening of the test container and extends into the test container, the other end of the gas exhaust pipeline is connected with a flow meter, the sample vessel is placed at the bottom of the test container, a recess is formed in the top of the sample vessel, the sample is placed in the recess, and; the samples were placed in the test vessel just before the start of the test but were not mixed with each other before the start of the test, and as water was injected, the samples were brought into mixing contact with the water and reacted.

In the above technical solution, preferably, the sample vessel is made of polytetrafluoroethylene or glass.

In the above technical solution, preferably, the test container is a glass-made sealed container.

In the above technical solution, preferably, before the test is started, the sample is uniformly placed on the sample dish, and then vaseline is applied to the cap of the test container, and the cap of the test container is closed.

In the above technical solution, preferably, when the test is started, the precision peristaltic pump is opened, water is injected into the test container at a constant rate of not more than 2ml/min, and at this time, the gas production rate a displayed by the flow meter is the rate B of gas exhaust caused by the injected water, where a is B; when the injected water contacts with the sample and reacts with the sample to generate gas along with the injection of the water, the flow meter displays a velocity A1, the velocity B of the discharged gas caused by the injection of the water is constant, A1 is more than B, and the difference A1-B is C, namely the velocity of the gas generated by the reaction of the sample and the water; after the water injection is finished, the gas production rate A2 displayed by the flowmeter is the rate of the gas generated by the reaction of the sample and the water.

In the above technical solution, preferably, the depth of the recess is 0.3 cm.

In the above technical solution, preferably, the flow meter is a constant pressure type gas flow meter, which keeps consistent with the pressure in the test bottle during operation, and can measure a very small flow rate less than 0.01 ml/min.

In the above technical scheme, preferably, an electromagnetic valve is arranged on a water injection pipeline at the outlet of the precision peristaltic pump.

The invention mainly solves the problems that after the test is started, water is added into the experimental container and reacts with a sample, and the water continuously enters the experimental container in the period of time to cause the pressure in the container to change; due to the defects of the test method, the deflation rate recorded by the instrument at this time is not the rate of gas evolution due to the reaction of the substance with water, and the period of time just after the substance and the water start to contact is the most violent time period of the reaction, so the calculated maximum deflation rate is not accurate. Meanwhile, a high-precision flowmeter is adopted to accurately record all gases generated in the whole test process, and the maximum deflation rate can be automatically calculated. The technical scheme of this patent can be solved and the gas production rate distortion problem during the application of sample that often can appear in the test method that detects the amount of gassing through the velocity of flow of gassing can be guaranteed the gas production rate that records for the true rate that sample and water reaction produced gaseously, has obtained better technological effect.

Drawings

FIG. 1 is a schematic flow diagram of the process of the present invention.

In fig. 1, 1 is a test container, 2 is a test container cover, 3 is a precision peristaltic pump, 4 is a sample dish with a concave top end, 5 is a sample, and 6 is water.

The present invention will be further illustrated by the following examples, but is not limited to these examples.

Detailed Description

[ example 1 ]

A sample mixing method for measuring the gas production rate of a substance reacted with water is characterized in that a test device for measuring the gas production rate of the substance reacted with water is adopted to carry out a gas production rate measurement test of the substance reacted with water, the device (shown in figure 1) comprises a test container, a test container cover, a precise peristaltic pump, a sample vessel and a gas exhaust pipeline, the gas exhaust pipeline penetrates through the container cover of a top opening of the test container and extends into the test container, the other end of the gas exhaust pipeline is connected with a flow meter, the sample vessel is placed at the bottom of the test container, a recess is formed in the top of the sample vessel, the sample is placed in the recess, and; the samples were placed in the test vessel just before the start of the test but were not mixed with each other before the start of the test, and as water was injected, the samples were brought into mixing contact with the water and reacted.

The test container was a glass-made sealed container. The sample vessel is made of polytetrafluoroethylene or glass. The peristaltic pump is arranged outside the test container, is connected with the bottom of the test container through a pipeline, and is sealed at the interface.

Before the test is started, the sample is placed evenly on the sample dish, and then vaseline is applied to the lid of the test container and the lid of the test container is closed.

When the test is started, a precision peristaltic pump is started, water is injected into a test container at a constant speed of less than or equal to 2ml/min, the gas production rate A displayed by a flow meter is the rate B of gas exhaust caused by water injection, and A is equal to B; when the injected water contacts with the sample and reacts with the sample to generate gas along with the injection of the water, the flow meter displays a velocity A1, the velocity B of the discharged gas caused by the injection of the water is constant, A1 is more than B, and the difference A1-B is C, namely the velocity of the gas generated by the reaction of the sample and the water; after the water injection is finished, the gas production rate A2 displayed by the flowmeter is the rate of the gas generated by the reaction of the sample and the water.

The scheme perfectly solves the problem that the pressure and the gas flow speed in the test container are changed due to the flowing of water during the mixing of water and the sample, effectively eliminates the interference factors caused by the change, and can accurately measure the speed of the sample reacting with the water to release the gas, thereby accurately obtaining the danger and the danger degree of the sample.

[ example 2 ]

The mancozeb gas evolution rate on water was tested according to the conditions and procedures described in example 1, with the following test procedures:

(1) putting 25.0g of mancozeb into a groove on a sample vessel with a concave top end;

(2) coating vaseline on the bottle mouth of the test container cover, and then covering and sealing the test container cover;

(3) setting a water injection mode of a precision peristaltic pump, continuously injecting 200ml of water, and keeping the constant speed at 10 ml/min;

(4) starting the test, water is injected into the test vessel at a constant rate, at which time the flow meter rate should be 0ml/min (the software automatically deducts the rate of water injection);

(5) in the water injection process, the software automatically deducts the water injection rate, after the water injection is completed, the software automatically closes the precision peristaltic pump, the water injection rate is not deducted at the moment, and all gas flow generated in the process is the gas flow generated by the reaction of the sample in water.

(6) After the test was completed, the water and sample were drained.

The test results were as follows: the gas generation rate of the mancozeb in water is 0.

[ example 3 ]

The ferrosilicon gas evolution rate on water was tested according to the conditions and procedures described in example 1 and the results are as follows: ferrosilicon, maximum water-meeting air release rate: 0.1359L/kg.h.

[ COMPARATIVE EXAMPLE ]

In the existing test method, a sample is added into a conical flask before the test, after the test is started, water is quickly injected into the conical flask from a glass container on the conical flask by using the gravity of the water, so that the sample and the water are mixed, and then the test is carried out. The initial stage of mixing the sample and the water is the most violent reaction stage with the largest gas production, but in the stage, the gas flow speed in the bottle is increased suddenly due to the fact that the water enters the conical bottle quickly, and the measured data is the sum of the flow generated by the gas in the bottle interfered by the water and the flow generated by the reaction of the sample when the water meets the water and cannot be distinguished. Thus, the test data measured by this method is inaccurate.

In the existing method, after the test is started, the water injection rate is constant, the water injection is slowly carried out from the bottom of the container, no air flows, the water injection is set to be Xml/min, 200ml is injected, and the water injection is carried out once every 5 seconds, so that the water injection amount can be calculated every time, Y is the amount of air exhausted due to the water injection, the gas production amount measured by the equipment is M in the 5 second time period, the gas amount generated by the reaction of the sample and the water is Y-M-Z, and the Z is converted into the gas flow rate through data processing.

Reagent test data (ferrosilicon, 25.0g, 200ml water, 20.0 ℃): according to the existing method, the maximum gas release rate when meeting water is 0.2096L/kg.h, the maximum gas release rate is 1.5921L/kg.h in the interval of 50-3649 seconds, the maximum gas release rate in the interval of 1-49 seconds is not the actual gas generation rate at all, and the interference is great, and the data are generally removed and are not used. By adopting the method, the maximum gas release rate when meeting water, which is 0.1359L/kg.h, is within the interval of 1-3600 seconds, and the actual gas generation rate can also be obtained as follows: the time period during which the reaction rate is highest is the initial stage.