Greenhouse gas collecting device for soil culture test

Abstract

The utility model belongs to the technical field of greenhouse gas collection, and particularly relates to a soil culture test greenhouse gas collection device which comprises a tank body, a fan, an exhaust pipe and a three-way valve, the fan is installed on one side in the tank body, the exhaust pipe communicated with the inside is arranged on the other opposite side of the tank body, and the exhaust pipe is connected with an exhaust pump. A three-way valve for controlling opening and closing of the exhaust pipe is arranged on the exhaust pipe; a soil filling upper limit line is arranged on the inner wall of the tank body; a sponge piece and / or a preservative film are / is arranged at the top of the tank body, the sponge piece is arranged in the tank body, and the preservative film covers the top of the tank body. According to the utility model, CO2, CH4, N2O or NH3 discharged by soil can be collected through one set of collection device, and CO2, CH4, N2O and NH3 discharged by soil can also be simultaneously collected through one set of collection device, so that more test requirements can be met, the structure is simple, the operation is easy, and the application range is wide.

Description

Technical Field

[0001] The utility model belongs to the technical field of greenhouse gas collection, and particularly relates to a greenhouse gas collection device for soil culture experiments. Background Art

[0002] Soil is an important greenhouse gas emission source. Exploring the law of soil greenhouse gas emission through culture experiments is a common technical means for scientific research personnel. However, the current gas collection method for culture experiments can only collect CO 2 , CH 4 , N 2 O or NH 3 emitted by the soil, and it is impossible to collect four greenhouse gases with the same set of devices, let alone collect these four greenhouse gases simultaneously with the same set of devices. Therefore, how to collect four greenhouse gases with one set of devices is an actual problem that needs to be overcome in scientific research work. Content of the Utility Model

[0003] In order to solve the problem that the existing technology cannot collect four soil greenhouse gases with the same set of culture experiment devices, the purpose of the utility model is to provide a greenhouse gas collection device for soil culture experiments.

[0004] The purpose of the utility model is realized through the following technical solutions:

[0005] The utility model includes a tank body, a fan, an air extraction pipe and a three-way valve. A fan is installed on one side inside the tank body. On the opposite side of the tank body, there is an air extraction pipe communicated with the inside, and the air extraction pipe is connected to an air extraction pump. A three-way valve for controlling the switch of the air extraction pipe is arranged on the air extraction pipe; a soil filling upper limit line is arranged on the inner wall of the tank body; a sponge sheet and / or a plastic wrap are arranged on the top of the tank body. The sponge sheet is placed inside the tank body, and the plastic wrap covers the top of the tank body.

[0006] Among them: the sponge sheet has two upper and lower layers, and each layer of the sponge sheet is soaked with a glycerol phosphate solution.

[0007] Two upper and lower groups of fixing blocks are arranged near the top inside the tank body. Each group of fixing blocks is a plurality of uniformly arranged along the circumferential direction, and a sponge sheet is placed on each group of fixing blocks.

[0008] The end face of the fixing block is a right triangle, and one right side of the right triangle is fixedly connected to the inner wall of the tank body, and the other right side is used to support the sponge sheet.

[0009] The fan is inclined with respect to the inner wall of the tank body. The fan is connected to a power supply device installed on the outer wall of the tank body through an electric wire and is controlled to rotate by a switch on the power supply device.

[0010] The tank body is a hollow structure with one end open and the other end closed, and the fan and the air extraction pipe are respectively located on both sides of the axial section of the tank body.

[0011] The advantages and positive effects of the present utility model are as follows:

[0012] With a set of collection devices, the present utility model can collect CO 2 , CH 4 , N 2 O or NH 3 emitted from the soil. It can also simultaneously collect CO 2 , CH 4 , N 2 O and NH 3 emitted from the soil with a set of collection devices, which can meet more test requirements, has a simple structure, is easy to operate, and has a wide application range. Description of the Drawings

[0013] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0014] Wherein: 11 is the tank body, 12 is the fixing block, 13 is the three-way valve, 14 is the air extraction pipe, 15 is the upper limit line of soil filling, 21 is the power supply device, 22 is the switch, 23 is the electric wire, and 24 is the fan. Detailed Embodiment

[0015] The present utility model will be further described in detail below with reference to the drawings.

[0016] As Figure 1 shown, the present utility model includes a tank body 11, a fan 24, an air extraction pipe 14 and a three-way valve 13. Among them, a fan 24 is installed on one side inside the tank body 11, and an air extraction pipe 14 communicating with the inside is provided on the opposite side of the tank body 11. The air extraction pipe 14 is connected to an air extraction pump, and a three-way valve 13 for controlling the switch of the air extraction pipe 14 is provided on the air extraction pipe 14; an upper limit line 15 of soil filling is provided on the inner wall of the tank body 11; a sponge sheet and / or plastic wrap is provided on the top of the tank body 11. The sponge sheet is placed inside the tank body 11, and the plastic wrap covers the top of the tank body 11.

[0017] In this embodiment, the tank body 11 is a PVC cylindrical plastic pipe with one end open, the other end closed, a height of 40 cm and a diameter of 16 cm. The fan 24 and the air extraction pipe 14 are respectively located on both sides of the axial section of the tank body 11, and the air extraction pipe 14 is 15 cm away from the top of the tank body 11.

[0018] In this embodiment, two sets of fixing blocks 12 are arranged at a position near the top inside the tank body 11, and each set of the fixing blocks 12 is a plurality of fixing blocks uniformly arranged along the circumferential direction. The fixing blocks 12 in this embodiment are made of plastic, with a total of eight, four in each group. The four fixing blocks 12 in the first group are located 2 cm away from the top of the tank body 11, and the four fixing blocks 12 in the second group are located 9 cm away from the top of the tank body 11. A circular sponge sheet is placed on each set of fixing blocks 12. The end face of the fixing block 12 in this embodiment is a right triangle, with both right sides being 1 cm and the thickness being 0.5 cm. One right side of the right triangle is fixedly connected to the inner wall of the tank body 11, and the other right side is used to support the sponge sheet. The sponge sheet of each layer is soaked with a glycerol phosphate solution.

[0019] In this embodiment, the upper limit line 15 of soil filling is 10 cm away from the bottom of the tank body 11.

[0020] In this embodiment, the fan 24 is inclined with respect to the inner wall of the tank body 11 at an inclination angle of 45 degrees. The fan 24 is 10 cm away from the top of the tank body 11. The fan 24 is connected to a power supply device 21 installed on the outer wall of the tank body 11 through an electric wire 23, and its rotation is controlled by a switch 22 on the power supply device 21.

[0021] The collection method of the present utility model is as follows:

[0022] When collecting NH 3 , put the culture soil into the tank body 11, then place the sponge sheet soaked with glycerol phosphate solution inside the top of the tank body 11, and then start timing. After a specified time, take out the sponge sheet and put it into a bottle, add KCL solution to the bottle, and then put the bottle into a rotary shaker for shaking, and the NH 3 extract solution discharged from the culture test soil within the specified time can be obtained. Measure the extract solution filtered by quantitative filter paper to calculate the soil NH 3 emission rate;

[0023] When collecting CO 2 , CH 4 , N 2 O, put the culture soil into the tank body 11, then cover and seal the top of the tank body 11 with a plastic film. At different specified time intervals after sealing, collect the gas inside the tank body 11 through the air extraction pipe 14. Before each collection starts, turn on the fan 24 for a set time to mix the gas. After the collection is completed, close the three-way valve 13. Since the culture test is carried out in an incubator, the temperature is recorded as the set temperature of the incubator when collecting the gas. The collected gas can be used to measure CO 2 , CH 4 , N 2 O. By measuring CO 2 , CH 4 , N2 The concentration of O is measured, and the CO emission rate of the soil in the culture experiment can be calculated. 2 and CH 4 and N 2 O emission rate;

[0024] When collecting CO 2 and CH 4 and N 2 O and NH 3 At that time, the culture soil is loaded into the tank body 11, and then a sponge sheet soaked with glycerol phosphate solution is placed inside the top of the tank body 11. After placing the sponge sheet, the top of the tank body 11 is covered and sealed with plastic wrap. At different specified time intervals after sealing, the gas inside the tank body 11 is collected through the suction pipe 14. Before each collection starts, the fan 24 is turned on for a set time to mix the gas. After the collection is completed, the three-way valve 13 is closed. Since the culture experiment is carried out in an incubator, the temperature is recorded as the set temperature of the incubator when collecting the gas. The collected gas can be used to measure the concentration of CO 2 and CH 4 and N 2 O concentration. By measuring the concentration of CO 2 and CH 4 and N 2 O collected at different specified time intervals, the CO 2 and CH 4 and N 2 O emission rate of the soil in the culture experiment can be calculated; after the gas is collected for the last time, the plastic wrap covering the top of the tank body 11 is opened, the sponge sheet is taken out and put into a bottle, KCL solution is added to the bottle, and then the bottle is placed in a rotary shaker for shaking, and the NH 3 extract solution emitted by the soil in the culture experiment for the specified time can be obtained. By measuring the extract solution after filtering with quantitative filter paper, the NH 3 emission rate of the soil can be calculated.

[0025] Experimental Example 1

[0026] The culture soil is loaded into the tank body 11, the weight of the soil is 2 kg, and the bulk density of the field soil when collecting the soil is 1.2 g / cm 3 . In order to keep the bulk density consistent with that of the field soil, the soil in the tank body 11 is flattened so that the filling height of the soil is 8.3 cm.

[0027] After the above soil is filled, a circular sponge sheet with a diameter of 16.5 cm and a thickness of 2 cm soaked with glycerol phosphate solution is placed on each of the two fixing blocks 12, and the amount of glycerol phosphate solution used is 15 ml. The upper sponge sheet is to prevent NH 3Effect on the lower sponge sheet. The preparation method of the glycerol phosphate solution is to mix 50 ml of phosphoric acid with 40 ml of glycerol and make up the volume to 1000 ml with deionized water to obtain the glycerol phosphate solution.

[0028] Start timing after placing the sponge sheet. After 24 h, take out the upper and lower sponge sheets. Put the lower sponge sheet into a bottle, add 300 ml of 2 mol / L KCl solution to the bottle, and shake it in a rotary shaker at 160 r / h for 1 h to obtain the NH 3 extract of the soil emissions during the 24-h incubation test. Measure the extract after filtering it through quantitative filter paper to calculate the soil NH 3 emission rate.

[0029] The time to take out the sponge sheet can be adjusted according to the actual needs of the incubation test. The time difference between taking out the sponge sheet and placing the sponge sheet is the NH 3 emission of the soil during this period.

[0030] Example 2

[0031] Load the soil for cultivation into the tank body 11. The weight of the soil is 2 kg, and the bulk density of the field soil during soil collection is 1.4 g / cm 3 , To keep the bulk density consistent with that of the field soil, the soil in the tank body 11 is flattened so that the filling height of the soil is 7.1 cm.

[0032] After the above-mentioned soil is filled, cover the top of the tank body 11 with plastic wrap and seal it with a rubber band. Collect the gas in the tank body 11 through the air extraction pipe 14 at 0 h, 1 h, and 2 h after sealing. Turn on the fan for 10 s before each sampling to mix the gas, and immediately close the three-way valve 13 after sampling; Since the incubation test is carried out in an incubator, the temperature is recorded as the set temperature of the incubator when collecting the gas. The collected gas can be used to measure the concentrations of CO 2 , CH 4 and N 2 O. By measuring the concentrations of CO 2 , CH 4 and N 2 O collected at 0 h, 1 h, and 2 h, the CO 2 , CH 4 and N 2 O emission rates of the soil in the incubation test can be calculated.

[0033] Example 3

[0034] Load the soil for cultivation into the tank body 11. The weight of the soil is 2 kg, and the bulk density of the field soil during soil collection is 1.3 g / cm 3 , To keep the bulk density consistent with that of the field soil, the soil in the tank body 11 is flattened so that the filling height of the soil is 7.7 cm.

[0035] After the above-mentioned soil is filled, a circular sponge sheet soaked with glycerol phosphate solution with a diameter of 16.5 cm and a thickness of 2 cm is placed on each of the two layers of fixing blocks 12, and the amount of glycerol phosphate solution used is 15 ml. The upper sponge sheet is to prevent the influence of the external air in the greenhouse gas collection device for soil culture experiments on the 3 lower sponge sheet. The preparation method of the glycerol phosphate solution is to mix 50 ml of phosphoric acid with 40 ml of glycerol and make up the volume to 1000 ml with deionized water to obtain the glycerol phosphate solution. After placing the sponge sheets, immediately cover the top of the tank body 11 with plastic wrap and wind it tightly with a rubber band. At 0 h, 1 h, and 2 h after sealing, collect the gas in the tank body 11 through the air extraction pipe 14. Turn on the fan for 10 s before each sampling starts, and immediately close the three-way valve 13 after the sampling ends; since the culture experiment is carried out in an incubator, the temperature is recorded as the set temperature of the incubator when collecting the gas. The collected gas can be used to measure the concentrations of CO 2 , CH 4 and N 2 O. By measuring the concentrations of CO 2 , CH 4 and N 2 O collected at 0 h, 1 h, and 2 h, the soil CO 2 , CH 4 and N 2 O emission rates in the culture experiment can be calculated.

[0036] Immediately after the last gas collection, open the plastic wrap on the top of the tank body 11.

[0037] After placing the sponge sheets for 24 h, take out the upper and lower sponge sheets. Put the lower sponge sheet into a bottle, add 300 ml of 2 mol / L KCl solution to the bottle, and oscillate it in a rotary shaker at 160 revolutions / h for 1 h to obtain the NH 3 extract of the soil discharged in the 24-h culture experiment. Measure the extract after filtering with quantitative filter paper to calculate the soil NH 3 emission rate.

[0038] The time to take out the sponge sheets can be adjusted according to the actual needs of the culture experiment. The time difference between taking out the sponge sheets and placing the sponge sheets is the NH 3 emission of the soil during this period.

[0039] The above is only the preferred embodiment of the present utility model, and does not limit the patent scope of the present utility model accordingly. Any equivalent structure or equivalent process exchange made by using the content of the specification and drawings of the present utility model, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of the present utility model by the same token.

Claims

1. A greenhouse gas collection device for soil culture experiments, characterized in that: The invention comprises a tank body (11), a fan (24), an exhaust pipe (14) and a three-way valve (13), wherein a fan (24) is installed on one side of the tank body (11), an exhaust pipe (14) communicating with the inside is provided on the other side opposite to the tank body (11), the exhaust pipe (14) is connected to an exhaust pump, and a three-way valve (13) for controlling the switch of the exhaust pipe (14) is provided on the exhaust pipe (14); a soil filling upper limit line (15) is provided on the inner wall of the tank body (11); a sponge sheet and / or a preservative film is provided on the top of the tank body (11), the sponge sheet is placed inside the tank body (11), and the preservative film covers the top of the tank body (11).

2. The greenhouse gas collection device for soil culture test according to claim 1, characterized in that: The sponge sheet comprises two layers, an upper layer and a lower layer, and each layer of the sponge sheet is soaked in glycerol phosphate solution.

3. The greenhouse gas collection device for soil culture test according to claim 1, characterized in that: Two groups of upper and lower fixing blocks (12) are arranged near the top of the tank body (11), each group of fixing blocks (12) is a plurality of fixing blocks evenly arranged along the circumferential direction, and a sponge sheet is placed on each group of fixing blocks (12).

4. The greenhouse gas collection device for soil culture test according to claim 3, characterized in that: The end face of the fixing block (12) is a right triangle, one right-angled side of the right triangle is fixedly connected to the inner wall of the tank body (11), and the other right-angled side is used to support the sponge sheet.

5. The greenhouse gas collection device for soil culture test according to claim 1, characterized in that: The fan (24) is arranged obliquely with respect to the inner wall of the tank body (11); the fan (24) is connected to a power supply device (21) installed on the outer wall of the tank body (11) via an electric wire (23); and its rotation is controlled by a switch (22) on the power supply device (21).

6. The greenhouse gas collection device for soil culture test according to claim 1, characterized in that: The tank body (11) is a hollow structure with one end open and the other end closed, and the fan (24) and the exhaust pipe (14) are respectively located on both sides of the axial cross section of the tank body (11).

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