CN110487611A - A pretreatment device and pretreatment method for measuring total mercury content in soil - Google Patents

Abstract

The invention discloses a pretreatment device and a pretreatment method for determining the total mercury content in soil, including a sample tube assembly for placing soil samples, a dosing device for adding super water and reagents to the sample, and a A vibrating device for shaking the sample tube after dosing, and a steaming heating device for heat treatment; the dosing device includes a dosing base and a dripping device, and the dosing base is provided with a sliding assembly, The dripping device includes a dripping device body and a dripping head, the dripping head is arranged on the sliding assembly and the super water, medicine and power are provided by the dripping device body; the overall structure of the present invention is reasonable and the degree of automation is high.

Description

A pretreatment device and pretreatment method for measuring total mercury content in soil

technical field

The invention relates to the technical field of soil detection, in particular to a pretreatment device and a pretreatment method for measuring the total mercury content in soil.

Background technique

In the analysis and determination of heavy metals in soil, the pretreatment of samples is the key. Pretreatment will directly determine the detection concentration, accuracy and precision of the entire analytical method. During the entire detection and analysis process, about 60% of the analysis errors come from sample pretreatment rather than the instrument itself.

Currently, when measuring the total heavy metal content in soil, the pretreatment methods used are wet method and dry method. Due to the simple conditions and easy operation of wet digestion, it is also a commonly used pretreatment method in laboratories. However, compared with the determination of mercury in soil, since mercury is easily decomposed by heat, it is not suitable for traditional wet digestion for pretreatment. At present, when measuring the total mercury content in soil, the boiling water bath method is mostly used. However, due to its complicated operation, the whole process is basically a human operation process, so it has a large error rate. At present, there is no pretreatment device with a high degree of automation for the determination of total mercury content in soil.

Contents of the invention

In view of the above-mentioned problems, the present invention provides a highly automated pretreatment device for measuring the total mercury content in soil on the one hand; another aspect of the present invention proposes a pretreatment method for measuring the total mercury content in soil.

In order to solve the above technical problems, the technical solution of the present invention is: a pretreatment device for measuring the total mercury content in soil, including a sample tube assembly for placing soil samples, for adding super water and reagents to the samples A device, a vibrating device for shaking the sample tube after dosing, and a steaming heating device for heat treatment;

The sample tube includes a sample tube and a tube holder, and the sample tube can be placed on the tube holder movably; the sample tube adopts a 50mL plugged colorimetric tube; A sliding assembly is arranged on the medicine base, and the dripping device includes a dripping device body and a dripping head, and the dripping head is arranged on the sliding assembly and super water, medicine and power are provided by the dripping device body; the medicine It includes a first medicament and a second medicament, the first medicament is aqua regia at a ratio of 1:1, and the second medicament is a 5% K ₂ Cr ₂ O ₇ solution.

Further, it also includes a device base, on which a linear guide rail is arranged; the drug dosing device, vibration device, and steaming heating device are sequentially arranged on the device base from left to right, and a slide table is installed on the linear guide rail; Use the base of the device to set up the dosing device, vibration device, and steaming heating device at one time. During the pretreatment process, the actual operation is more convenient; at the same time, the linear guide rail and sliding table can effectively realize automatic control, which greatly reduces the cost. The workload of the staff.

Further, the dosing base is movably arranged on the left side of the device base through the installation frame, and the dripping head includes a dripping head cavity, a first liquid inlet, a second liquid inlet, a third liquid inlet, and a cylinder valve; An inner plug is provided at the drip port at the lower end of the dripping head cavity; a hollow piston rod is provided inside the cylinder valve;

The first liquid inlet, the second liquid inlet, and the third liquid inlet are respectively communicated with the cavity of the dripping head, and are respectively used to transmit the first medicine, the second medicine, and super water; the cylinder valve is arranged at The upper end of the dripping head cavity, and the hollow piston rod is connected with the inner plug, and the inner plug is used to close the dripping port at the lower end of the dripping head cavity; and a gasket is arranged at the contact between the inner plug and the dripping port; the dripping head There are three liquid inlets inside to realize the separate and independent dripping of super water, the first medicine and the second medicine; at the same time, the cylinder valve can further ensure the sealing of the dripping head and the optional dripping operation.

Further, the vibration device includes a mounting bracket, a first telescopic device, and a vibration assembly; the mounting bracket is movably arranged on the device base, and the vibration assembly is arranged on the top of the mounting bracket through the first telescopic device; using

There are locking grooves on the left and right sides of the pipe bracket;

The vibration assembly includes a mounting base, a vibration motor, a vibration plate, a connecting spring, and an electric plug lock; the mounting base is a door-shaped structure, and the mounting base is installed at the lower end of the first telescopic device; the vibration motor is arranged on the mounting base; There are two vibrating plates, and the two vibrating plates are respectively installed on the left and right ends of the mounting seat through two connecting springs; the dead bolt of the electric mortise lock can be inserted into the lock groove; through the electric mortise lock, the lock groove The tube bracket can be movably installed on the vibrating plate, and then the sample tube on the tube bracket can be shaken evenly by the vibrating motor.

Further, the steam heating device includes an outer protective shell, an inner protective shell, a second telescopic device and a steam generating device;

The outer protective shell is installed on the base of the device, the inner protective shell is arranged on the inner top of the outer protective shell through the second telescoping device, and a conduit/spray assembly is arranged on the inner side of the inner protective shell; The above-mentioned conduit/spray assembly adopts a stainless steel pipe with pores evenly opened on the pipe wall, and the conduit/spray assembly is connected with the steam generating device; the sample to be tested can be digested through the steam generating device, and the inner and outer protective shells can further Guaranteed safety during digestion.

Further, the steam heating device also includes a steam condenser, the steam condenser is arranged inside the outer protective shell, and the steam condenser is connected to the inner top of the inner protective shell through a conduit; the steam condenser can further Treating the treated steam and converting the heat of the steam can effectively avoid accidents caused by direct steam discharge.

Further, the pretreatment method utilizing said device to measure the total mercury content in soil is characterized in that, comprising the following steps:

Step 1: Place 0.5g of the soil sample to be tested in the sample tube, and place the sample tube on the tube holder; then place the tube holder on the dosing base and add a few drops of super water to the sample tube through the dripping head. After the soil to be tested is wetted; then add 10mL of 1:1 aqua regia to the wetted soil; stopper;

Step 2: Place the pipe bracket on the sliding table, slide it to the bottom of the vibration device, adjust the vibration component to move down through the first telescopic device, and then insert the bolt of the electric mortise lock into the lock groove; adjust the first telescopic device to rise After the tube bracket is suspended in the air, turn on the vibration motor to shake the sample tube. The specific shaking time is 5 to 15 minutes; then turn off the vibration motor, place the tube bracket on the sliding table through the first telescopic device, and then close the lock tongue. Then adjust the first telescopic device to rise to the initial position;

Step 3: Slide the tube holder directly under the protective shell through the slide table, and lower the protective shell to contact with the base of the device through the second telescopic device; open the steam generator and use the conduit/spray assembly to make the steam continue to heat the sample tube for 1.5 After h, close the steam generating device and use the second expansion device to restore the protective shell to the original position; after cooling for 20-30 minutes;

Step 4: Use the slide table to slide the tube holder to the initial position, then place the tube holder on the dosing base and add 1 to 2 drops of K ₂ Cr ₂ O ₇ solution to the sample tube through the dripping head; then use the dropper After adding super water to the sample tube to make it up to the mark line of the sample tube, repeat step 2 to shake well and let it stand still.

Compared with the prior art, the beneficial effect of the present invention is that the overall structure of the present invention is reasonable, and the degree of automation is high, which can effectively reduce the labor workload of the staff in the laboratory; moreover, the present invention uses steam heating for digestion, and the entire digestion time It is short, and using the device of the present invention can realize multiple groups of samples to be processed at the same time; the use of the dosing device can effectively prevent the staff from contacting the reagents during the pretreatment process, and effectively avoid the danger caused by corrosive reagents; The determination of the mercury element after the sample is processed by the pretreatment device and method of the present invention has relatively high accuracy, all of which are within the error range of the guaranteed value of each sample, and are suitable for mass promotion.

Description of drawings

Fig. 1 is a schematic diagram of the internal structure of the present invention;

Fig. 2 is a schematic diagram of the external structure of the present invention;

Fig. 3 is a schematic structural view of the bracket of the present invention;

Fig. 4 is a schematic structural view of the vibrating assembly of the present invention;

Fig. 5 is the structural representation of dripping head of the present invention;

Among them, 1-sample tube assembly, 11-sample tube, 12-tube holder, 120-lock slot, 2-dosing device, 21-dosing base, 210-sliding assembly, 22-dropping device, 221-dropping Head, 2210-drip head cavity, 2211-first liquid inlet, 2212-second liquid inlet, 2213-third liquid inlet, 2214-inner plug, 2215-gasket, 3-vibration device, 31- Mounting bracket, 32-first telescopic device, 33-and vibrating assembly, 331-mounting seat, 332-vibrating motor, 333-vibrating plate, 334-connecting spring, 335-electric plug lock, 4-steam heating device, 41 -External protective shell, 42-Inner protective shell, 420-Conduit/spray assembly, 43-Second telescopic device, 44-Steam generating device, 5-Device base, 51-Linear guide rail, 6-Cylinder valve, 61- Hollow piston rod.

Detailed ways

Embodiment: a kind of pretreatment device of determining total mercury content in soil as shown in Figure 1, 2, comprises the sample tube assembly 1 that is used to place soil sample, is used for adding the dosing device of super water and reagent in sample 2. A vibrating device 3 for shaking the sample tube 1 after dosing, a steaming heating device 4 for processing; and a device base for installing the dosing device 2, the vibrating device 3, and the heating device 4 5; The base 5 of the device is provided with a linear guide rail 51, and a slide table 52 is installed on the linear guide rail 51;

The sample tube 1 includes a sample tube 11 and a tube holder 12, and the sample tube 11 can be movably placed on the tube holder 12; the sample tube 11 adopts a 50mL plugged colorimetric tube;

The dosing device 2 includes a dosing base 21 and a dripping device 22, the dosing base 21 is provided with a sliding assembly 210, the dripping device 22 includes a dripping device body and a dripping head 221, and the dripping head 221 is arranged on the sliding assembly 210 And the dripping device body provides super water, medicine and power;

The dripping device body includes a liquid storage tank and a metering pump; the medicament includes a first medicament and a second medicament, the first medicament is 1:1 aqua regia, and the second medicament is a 5% K ₂ Cr ₂ O ₇ solution; the storage solution The box includes a first liquid storage tank, a second liquid storage tank and a third liquid storage tank, and the first liquid storage tank, the second liquid storage tank and the third liquid storage tank are respectively used to place the first medicine, the second medicine and the Super water;

As shown in Figures 1 and 5, the dosing base 21 is movably arranged on the left side of the device base 5 through the mounting frame, and the dripping head 221 includes a dripping head cavity 2210, a first liquid inlet 2211, a second liquid inlet 2212, The third liquid inlet 2213, the cylinder valve 6; an inner plug 2214 is provided at the drip port at the lower end of the drip head cavity 2210; a hollow piston rod 61 is provided in the cylinder valve 6;

The first liquid inlet 2211, the second liquid inlet 2212, and the third liquid inlet 2213 communicate with the drip head cavity 2210 respectively, and are connected with the first liquid storage tank, the second liquid storage tank and the third liquid storage tank respectively. Connected by an independent metering pump; the cylinder valve 6 is set at the upper end of the drip head cavity 2210, and the hollow piston rod 61 is connected with the inner plug 2214, and the inner plug 2214 is used to close the drip port at the lower end of the drip head cavity 2210 ; and a gasket 2215 is provided at the contact between the inner plug 2214 and the drip port;

The vibration device 3 includes a mounting bracket 31, a first telescopic device 32 and a vibration assembly 33; the mounting bracket 31 is movably arranged on the device base 5, and the vibration assembly 33 is arranged on the top of the mounting bracket 31 through the first telescopic device 32;

As shown in FIG. 3 , lock slots 120 are provided on the left and right end sides of the pipe support 12 ;

As shown in Figures 1 and 4, the vibration assembly 33 includes a mounting base 331, a vibration motor 332, a vibrating plate 333, a connecting spring 334, and an electric plug lock 335; the mounting base 331 is a door structure, and the mounting base 331 is installed on the first telescopic device 32 lower end; the vibrating motor 332 is arranged on the mount 331; there are two vibrating plates 333, and the two vibrating plates 333 are installed on the inside left and right ends of the mount 331 through two connecting springs 334 respectively; the bolt of the electric plug lock 335 can Insert into the lock slot 120;

The steam heating device 4 includes an outer protective casing 41, an inner protective casing 42, a second telescopic device 43 and a steam generating device 44;

The outer protective shell 41 is installed on the device base 5, the inner protective shell 42 is arranged on the inner top of the outer protective shell 41 through the second telescopic device 43, and the inner protective shell 42 is provided with a conduit/spray assembly 420 on the inner side; The conduit/spray assembly 420 adopts a stainless steel pipe with air holes evenly opened on the pipe wall, and the conduit/spray assembly 420 is connected with the steam generating device 44;

Wherein, the steam heating device 4 also includes a steam condenser, the steam condenser is arranged inside the outer protective shell 41, and the steam condenser is connected to the inner top of the inner protective shell 42 through a conduit;

It should be noted that this embodiment uses a PLC controller of the model GCAN-PLC produced by Guangcheng Technology, and this device needs to be connected to an external power supply.

Utilize the technique of the soil pretreatment of the device of the present embodiment to be measured total mercury content, comprise the following steps:

Step 1: Place 0.5g of the soil sample to be tested in the sample tube 11, and place the sample tube 11 on the tube holder 12; Add a few drops of super water to moisten the soil to be tested; then add 10mL of 1:1 aqua regia to the wetted soil; stopper;

Step 2: Place the pipe support 12 on the slide table 52, slide it to the right below the vibration device 3, adjust the vibration component 33 to move downward through the first telescopic device 32, and then insert the bolt of the electric plug lock 335 into the lock groove 120 After adjusting the first telescopic device 32 to rise so that the tube support 12 is suspended in the air, open the vibration motor 332 to shake the sample tube 11, and the specific shaking time is 10min; 12 After being placed on the slide table 52, the dead bolt is closed, and then the first telescopic device 32 is adjusted to rise to the initial position;

Step 3: Slide the pipe support 12 directly below the protective casing 42 through the slide table 52, and lower the protective casing 42 to contact with the device base 5 through the second telescopic device 43; open the steam generating device 44 and use the conduit/spray assembly 420 After the steam continues to heat the sample tube 11 for 1.5 hours, close the steam generating device 44 and use the second telescopic device 43 to restore the protective shell 42 to the original position; after cooling for 25 minutes;

Step 4: Slide the tube holder 12 to the initial position by using the slide table 52, and then place the tube holder 12 on the dosing base 21 and drop 2 drops of K ₂ Cr ₂ O ₇ solution into the sample tube 11 through the dripping head 221; Then use the dripping head 221 to add super water to the sample tube 11 to make it up to the mark line of the sample tube 11, repeat step 2 to shake well and then let it stand still.

Test example: The three soil samples collected ESS-1, ESS-2, and ESS-3 were pretreated by using the device and method of this embodiment, and then mercury was determined by ICP-MS. The determination results of mercury content in the samples are as follows:

Conclusion: Using the pretreatment device and method of this embodiment to pretreat the soil samples, the content of mercury element in the samples is within the error range of the guaranteed value of each sample, and the results are acceptable.

Claims (7)

1. A pretreatment device for measuring total mercury content in soil, comprising a sample tube assembly (1) for placing a soil sample, a dosing device (2) for adding super water and reagent to the sample, for A vibrating device (3) for shaking the sample tube (1) after adding the reagent, and a steaming heating device (4) for heat treatment; It is characterized in that the sample tube (1) comprises a sample tube (11) and a tube holder (12), and the sample tube (11) can be placed on the tube holder (12) movably; the sample tube (11) adopts a 50mL tool plug colorimetric tube; The dosing device (2) includes a dosing base (21) and a dripping device (22), the dosing base (21) is provided with a slide assembly (210), and the dripping device (22) includes a dripping device (22). The dripping device body and the dripping head (221), the dripping head (221) is arranged on the slide assembly (210) and the super water, medicine and power are provided by the dripping device body; the medicine includes the first medicine and the second medicine Two medicines, the first medicine is 1:1 aqua regia, and the second medicine is 5% K ₂ Cr ₂ O ₇ solution. 2. a kind of pretreatment device of measuring total mercury content in soil according to claim 1, is characterized in that, also comprises device base (5), and described device base (5) is provided with linear guide rail (51); The dosing device (2), vibrating device (3) and steam heating device (4) are sequentially arranged on the device base (5) from left to right, and a slide table (52) is installed on the linear guide rail (51). 3. a kind of pretreatment device for measuring total mercury content in soil according to claim 2, is characterized in that, described dosing base (21) is arranged on the left side of device base (5) movable by mounting frame, drips The head (221) comprises a dripping head cavity (2210), a first liquid inlet (2211), a second liquid inlet (2212), a third liquid inlet (2213), a cylinder valve (6); the dripping head An inner plug (2214) is provided at the drip opening at the lower end of the cavity (2210); a hollow piston rod (61) is provided inside the cylinder valve (6); The first liquid inlet (2211), the second liquid inlet (2212), and the third liquid inlet (2213) are respectively communicated with the drip head cavity (2210), and are respectively used to transmit the first medicine, the second Two medicaments, super water; the cylinder valve (6) is arranged on the upper end of the drip head cavity (2210), and the hollow piston rod (61) is connected with the inner plug (2214), and the inner plug (2214) is used for dripping The drip opening at the lower end of the head cavity (2210) is closed; and a gasket (2215) is provided at the contact between the inner plug (2214) and the drip opening. 4. A kind of pretreatment device for measuring total mercury content in soil according to claim 2, is characterized in that, described vibration device (3) comprises mounting bracket (31), first telescopic device (32) and vibration assembly (33); the installation bracket (31) is movably arranged on the device base (5), and the vibration assembly (33) is arranged on the top of the installation bracket (31) through the first telescopic device (32); Locking grooves (120) are provided on the left and right end sides of the pipe bracket (12); The vibration assembly (33) includes a mounting base (331), a vibration motor (332), a vibration plate (333), a connecting spring (334), and an electric plug lock (335); the mounting base (331) is a door-shaped structure , the mounting base (331) is installed on the lower end of the first telescopic device (32); the vibration motor (332) is arranged on the mounting base (331); the vibration plate (333) has two, and the two vibration plates (333 ) are respectively installed on the left and right ends of the mounting base (331) through two connecting springs (334); the dead bolt of the electric mortise lock (335) can be inserted in the lock groove (120). 5. a kind of pretreatment device of measuring total mercury content in soil according to claim 2, is characterized in that, described steam heating device (4) comprises and comprises external protective housing (41), internal protective housing ( 42), the second expansion device (43) and the steam generating device (44); The outer protective shell (41) is installed on the device base (5), the inner protective shell (42) is arranged on the inner top of the outer protective shell (41) through the second telescopic device (43), and A conduit/spray assembly (420) is provided on the inner side of the inner protective housing (42); the conduit/spray assembly (420) adopts a stainless steel pipe with air holes evenly opened on the pipe wall, and the conduit/spray assembly (420) is connected to the The steam generator (44) is connected. 6. utilize the pretreatment method of the device measurement total mercury content in soil any one of claim 1-5, it is characterized in that, comprise the following steps: Step 1: Place 0.5g of the soil sample to be tested in the sample tube (11), place the sample tube (11) on the tube support (12); then place the tube support (12) on the dosing base (21) Add a few drops of super water to the sample tube (11) through the dripping head (221) to moisten the soil to be tested; then add 10 mL of 1:1 aqua regia to the wetted soil; stopper; Step 2: Place the pipe support (12) on the slide table (52), slide it to the right below the vibration device (3), adjust the vibration component (33) to move downward through the first telescopic device (32), and then insert the electric plug The deadbolt of the lock (335) is inserted into the lock groove (120); the first telescopic device (32) is adjusted to rise so that the tube support (12) is suspended, and the vibrating motor (332) is turned on to shake the sample tube (11). The specific shaking time is 5 to 15 minutes; then turn off the vibrating motor (332), place the pipe support (12) on the slide table (52) through the first telescopic device (32) and close the dead bolt, and then adjust the first telescopic device (32). Device (32) rises to initial position; Step 3: Slide the pipe support (12) directly under the protective shell (42) through the slide table (52), and lower the protective shell (42) to contact with the device base (5) through the second telescopic device (43) ; Turn on the steam generating device (44) and utilize the conduit/spray assembly (420) to make the steam continue to heat the sample tube (11) for 1.5h, then close the steam generating device (44) and use the second telescopic device (43) to wrap the protective shell The body (42) returns to the initial position; after cooling for 20 to 30 minutes; Step 4: Use the slide table (52) to slide the tube support (12) to the initial position, then place the tube support (12) on the dosing base (21) into the sample tube (11) through the dripping head (221) Add 1 to 2 drops of K ₂ Cr ₂ O ₇ solution; then use the dripping head (221) to add super water to the sample tube (11) and make it up to the mark line of the sample tube (11), repeat step 2 to shake Let stand after mixing. 7 . A pretreatment device for measuring total mercury content in soil according to claim 1 , wherein the concentration of the K ₂ Cr ₂ O ₇ solution is 5%.