Method for Carrying out Whole-Process Treatment on Phytoplankton

Abstract

The present invention relates to the field of water environment treatment, and particularly discloses a method for carrying out whole-process treatment on phytoplankton. The method comprises: enabling a water body in the natural environment to first pass through a filtering device to remove large-sized particles in the water body; enabling the filtered water body to pass through a water pipe provided with multiple stages of permanent magnets to be subjected to pre-magnetization; then enabling the water body subjected to pre-magnetization to enter an equalization tank to be subjected to homogenization and/or flocculating sedimentation to separate phytoplankton and suspended particles in the water body; then for different growth phases of the phytoplankton, applying different magnetic field intensities for inhibiting and even directly killing the phytoplankton to implement optimization of cost and effects; and finally, carrying out aeration oxygenation on the magnetized water body and releasing the water body subjected to aeration oxygenation into the natural water environment.

Claims

1. A method for carrying out whole-process treatment on phytoplankton, comprising: enabling a water body in a natural environment to pass through a filtering device by utilizing a water pump to remove large-sized particles in the water body; enabling the filtered water body to pass through a water pipe provided with multiple stages of permanent magnets to be subjected to pre-magnetization treatment; pouring the water body subjected to pre-magnetization treatment into an equalization tank to be subjected to homogenization and/or flocculating sedimentation to separate phytoplankton and suspended particles in the water body; and carrying out magnetization treatment on the water body treated by magnetizers, carrying out aeration oxygenation on the magnetized water body to maintain dissolved oxygen concentration of the water body within a range of 15 to 20 mg/L, and releasing the water body subjected to aeration oxygenation into a natural water environment through a water distributing pipe.

2. The method according to claim 1, wherein a growth phase of the phytoplankton is determined according to a temperature of the water body, and for different growth phases, different magnetic field parameters are adopted to carry out magnetization treatment, wherein for the water body with the phytoplankton in a recovery period, a magnetic field with an intensity of 150 mT to 500 mT is applied for 1 to 5 min; and for the water body with the phytoplankton in a dormancy period or a growth period, a magnetic field with an intensity of 500 mT to 1,000 mT is applied for 5 to 20 min.

3. The method according to claim 2, wherein when magnetization treatment is carried out on the water body with the phytoplankton in the recovery period and a TP is greater than or equal to 0.02 mg/L, a magnetic field with an intensity of 300 mT to 500 mT is applied; and when magnetization treatment is carried out on the water body with the phytoplankton in the dormancy period or the growth period and the TP is greater than or equal to 0.02 mg/L, a magnetic field with an intensity of 800 mT to 1,000 mT is applied.

4. The method according to claim 1, wherein when chlorophyll a in the water body is greater than or equal to 26 mg/m.sup.3, a flocculant PAC is added into the equalization tank, the TP in the water body is used as a calculation basis, and an adding coefficient of the PAC is 1.5.

5. The method according to claim 4, wherein the filtering device is a grille with a rake tooth grille gap of 5 mm to 50 mm.

6. The method according to claim 5, wherein the permanent magnets are made of rare earth neodymium iron boron.

7. The method according to claim 6, wherein the water body subjected to aeration oxygenation is released into the natural water environment through the water distributing pipe, and when the phytoplankton in a primitive water body is in the dormancy and the recovery periods, the water body subjected to aeration oxygenation is uniformly distributed at a mud-water interface by the water distributing pipe; and when the phytoplankton in the primitive water body is in the growth period, the water body subjected to aeration oxygenation is uniformly distributed in a floating-up water by the water distributing pipe.

8. A system for carrying out whole-process treatment on phytoplankton, comprising: a water pump, a filtering device, a water pipe provided with multiple stages of permanent magnetic type magnetizers, an equalization tank, the permanent magnetic type magnetizers, an aeration oxygenation device, and a water distributing pipe which are sequentially arranged.

9. The whole-process treatment system according to claim 8, wherein the water pipe provided with multiple stages of permanent magnetic type magnetizers is formed by arranging the permanent magnetic type magnetizers at intervals of 10 to 50 cm around the water pipe.

10. The whole-process treatment system according to claim 9, wherein the magnetizers are adjustable permanent magnetic type magnetizers.

Description

DETAILED DESCRIPTION

[0044] Preferred embodiments of the present invention will be illustrated in detail below in connection with embodiments. It should be understood that embodiments given below are merely used for illustration, rather than limiting the scope of the present invention. Those of ordinary skill in the art, without departing from the purpose and the spirit of the present invention, can make various modifications and replacements to the present invention.

[0045] Experimental methods used in the below-mentioned embodiments, unless otherwise specifically illustrated, are all conventional methods.

[0046] Materials, reagents and the like used in the below-mentioned embodiments, unless otherwise specifically illustrated, all can be obtained by commercial approaches.

Embodiment 1

[0047] This embodiment is used for illustrating a system for carrying out whole-process treatment on phytoplankton, which comprises the following devices: a submersible pump, a coarse grille, a water inlet pipe provided with permanent magnets, an equalization tank, magnetization equipment, aeration oxygenation equipment, and a water distributing pipe which are sequentially connected.

[0048] Wherein, the submersible pump has a lift of 15 m and a power of 160 m.sup.3/h.

[0049] Wherein, the coarse grille has a grille gap of 40 mm and an installation angle of 60°.

[0050] Wherein, the water inlet pipe has a diameter of 160 mm and a length of 5 m; and raw materials of the permanent magnets are rare earth neodymium iron boron.

[0051] Wherein, the equalization tank is a cuboid device, and has a size of 3.0 m*1.5 m, an available water depth of 2 m and an effective volume of 9 m.sup.3.

[0052] Wherein, the magnetization equipment has a maximum treatment capacity of 5,000 m.sup.3/d and a magnetic field range of 50 mT to 2,500 mT.

[0053] Wherein, the aeration oxygenation equipment has an oxygen production capacity of 300 Kg/d, and can produce pure oxygen with a purity of 95%.

Embodiment 2 Treatment of Phytoplankton

[0054] This embodiment takes a heavy eutrophic rural pond water body as an example, and illustrates a method for carrying out treatment on phytoplankton by utilizing the system described in Embodiment 1.

[0055] After detection, a water temperature of the rural pond is 16 to 28 DEG C., the phytoplankton in the water body is in a growth period, chlorophyll a content of the water body reaches 78 μg/L, TP content of the water body reaches 0.33 mg/L, and the water body belongs to a heavy eutrophic water body.

[0056] The pond water body is lifted to the coarse grille by the submersible pump and passes through the coarse grille to remove large-particle rubbish, plant and animal residues and large-sized phytoplankton in the water body;

[0057] pre-magnetization is carried out on the filtered water body by the water inlet pipe provided with the permanent magnets, and a water flow rate is about 0.5 to 1.0 m/s;

[0058] the water body enters the equalization tank after being subjected to pre-magnetization treatment, homogenization is carried out by a stirrer, then a PAC flocculant is added, a dosage is 1.5 times the TP content, flocculating sedimentation is carried out on the water body, and the phytoplankton and suspended particles in the water body are separated; and

[0059] the water body subjected to flocculating sedimentation treatment is introduced into the magnetization equipment to be magnetized for 5 min under a magnetic field intensity of 800 mT, aeration oxygenation is carried out on the magnetized water body to maintain dissolved oxygen concentration of the water body within a range of 15 mg/L to 20 mg/L, and the obtained water body is discharged into the pond by the water distributing pipe.

[0060] The above-mentioned treatment is continued for 10d, Chl-a, TP and TN of the water body in the pond are monitored, algae cells in surface layer sediments (3 cm) are counted by utilizing a microscope, and a result is as shown in Table 1:

TABLE-US-00001 TABLE 1 Change Rate Change Change Change Change (%) of Number Rate Rate Rate Rate Treatment of Algae Cells (%) of (%) of (%) of (%) of Time in Sediments Chl-a TP TN BOD  0 d 0 0 0 0 0 10 d −21.2 −81.3 −45.7 −44.2 −71.2

Contrast Example 1

[0061] In order to research influence of magnetization treatment carried out on the water body on phytoplankton in different growth phases, this contrast example respectively adopts magnetization treatment and non-magnetization treatment (after passing through the equalization tank, the water body does not enter the magnetization equipment to be magnetized) in different growth phases of algae, after 10d, removal rates of chlorophyll a, TP, TN, BOD and COD in the water body are compared, and specific test indexes in the algae dormancy period, the algae recovery period and the algae growth period are respectively as shown in Table 2, Table 3 and Table 4.

TABLE-US-00002 TABLE 2 Comparison of Indexes in Algae Dormancy Period Change Magnetic Change Change Change Change Change Rate (%) Field Rate Rate Rate Rate Rate of Number Whether to Intensity (%) of (%) of (%) of (%) of (%) of of Algae in Period Magnetize (mT) Chl-a TP TN BOD COD Sediments Algae No 0 0 0 0 0 0 0 Dormancy Period Algae Yes 150 −32.9 −51.2 −15.2 −49.3 −41.2 −10.1 Dormancy Period Algae Yes 300 −49.7 −59.2 −15.2 −54.2 −47.3 −11.2 Dormancy Period Algae Yes 500 −62.3 −64.1 −17.3 −66.2 −61.8 −29.7 Dormancy Period Algae Yes 800 −67.2 −69.4 −21.4 −74.3 −67.2 −44.1 Dormancy Period Algae Yes 1,000 −66.7 −77.8 −21.9 −77.3 −65.7 −43.7 Dormancy Period

[0062] It can be known from Table 2 that in the algae dormancy period, a magnetic field intensity of 500 to 1,000 mT is the most effective for water quality improvement and removal of the algae on the surface layer of the sediments.

TABLE-US-00003 TABLE 3 Comparison of Indexes in Algae Recovery Period Change Magnetic Change Change Change Change Change Rate (%) Field Rate Rate Rate Rate Rate of Number Whether to Intensity (%) of (%) of (%) of (%) of (%) of of Algae in Period Magnetize (mT) Chl-a TP TN BOD COD Sediments Algae No 0 0 0 0 0 0 0 Recovery Period Algae Yes 150 −89.3 −69.6 −21.3 −71.9 −60.2 −17.2 Recovery Period Algae Yes 300 −94.2 −71.2 −24.5 −74.9 −61.9 −21.4 Recovery Period Algae Yes 500 −90.7 −71.2 −25.1 −73 −61.3 −20.2 Recovery Period Algae Yes 800 −83.1 −65.7 −21.9 −68.3 −57.6 −17.4 Recovery Period Algae Yes 1,000 −79.3 −61.2 −18.1 −63.7 −52.4 −18.7 Recovery Period

[0063] It can be known from Table 3 that in the algae recovery period, a magnetic field intensity of 150 to 500 mT is the most effective for water quality improvement and removal of the algae on the surface layer of the sediments.

TABLE-US-00004 TABLE 4 Comparison of Indexes in Algae Growth Period Change Magnetic Change Change Change Change Change Rate (%) Field Rate Rate Rate Rate Rate of Number Whether to Intensity (%) of (%) of (%) of (%) of (%) of of Algae in Period Magnetise (mT) Chl-a TP TN BOD COD Sediments Algae No 0 0 0 0 0 0 0 Growth Period Algae Yes 150 −68.3 −61.3 −20.3 −62.3 −50.2 −17.3 Growth Period Algae Yes 300 −71.2 −69.3 −25.9 −64.8 −54.1 −18.3 Growth Period Algae Yes 500 −78.3 −73.2 −30.4 −69.2 −61.2 −21.5 Growth Period Algae Yes 800 −87.8 −77.8 −33.1 −71.2 −65.2 −27.3 Growth Period Algae Yes 1,000 −88.3 −80.1 −33.1 −70.2 −62 −24.1 Growth Period

[0064] It can be known from Table 4 that in the algae growth period, a magnetic field intensity of 500 to 1,000 mT is the most effective for water quality improvement and removal of the algae on the surface layer of the sediments.

Embodiment 3 Regulation and Control of Gas Vesicles

[0065] In order to carry out validation on the present invention better, according to the present invention, laboratory validation is carried out on gas vesicles, three periods of algae are simulated by regulation of a temperature of a light incubator, algae in different growth periods are respectively subjected to magnetization and non-magnetization at temperatures of 5 DEG C., 15 DEG C. and 30 DEG C., volume size changes of the gas vesicles are compared, and a result is as shown in Table 5.

TABLE-US-00005 TABLE 5 Magnetic Change Rate Field (%) of volume Whether to Intensity Magnetization size of gas Period Magnetize (mT) Time (min) vesicles Algae No 0 0 0 Dormancy Period Algae Yes 800 5 0 Dormancy Period Algae No 0 0 0 Recovery Period Algae Yes 300 1 −69.1 Recovery Period Algae No 0 0 0 Growth Period Algae Yes 800 5 −77.4 Growth Period

[0066] Although the present invention has been described above in great detail with general descriptions and specific embodiments, on the basis of the present invention, various modifications or improvements may be made, which is apparent to those of ordinary skill in the art. Therefore, all such modifications and improvements without departing from the spirit of the present invention are within the scope of the claims of the present invention.