Method for treating spherical brown cystis red tide through combination of gel microsphere adsorption and ultrasound and regeneration method of gel microspheres

Abstract

The invention relates to the technical field of red tide treatment, in particular to a method for treating red tide of globocystis globosa through combination of gel microsphere adsorption and ultrasonic treatment and a regeneration method of gel microballoon.The method for treating the red tide of globocystis globosa through combination of gel microsphere adsorption and ultrasonic treatment comprises the steps that firstly, gel microspheres are prepared; and then, filling the gel microspheres into a filter bag to jointly treat the spherical brown cystis red tide in the water area together with an ultrasonic device. In addition, according to the regeneration method of the gel microspheres, the gel microspheres subjected to adsorption treatment are recycled for regeneration and reuse, and the effect of removing the globocystis globosa is still good. According to the method for treating the red tide of the globocystis globocystis, through the adsorption of the gel microspheres and the ultrasonic-assisted combined effect, the globocystis globocystis cells in a water body can be efficiently removed, and release of intracellular hemolytic toxins of the globocystis globocystis cells is avoided; meanwhile, a good effect of eliminating phosphate in a water body is achieved, and resuscitation and re-outbreak of red tide algae cells are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of red tide control, and in particular to a method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound, and a method for regenerating gel microspheres. Background Art

[0002] The P. spherical algae red tide is a harmful algal bloom phenomenon that has frequently occurred in many eutrophic coastal areas around the world in recent years. With the changes in the global environment and climate, the scope and frequency of P. spherical algae red tide outbreaks have increased year by year. Since the first outbreak of P. spherical algae red tide in the coastal areas of Guangdong, my country in 1997, it has occurred year after year in the southeastern coastal waters of Guangdong, Guangxi, Hainan, etc., and has also frequently occurred in the Bohai Sea and the South Yellow Sea in recent years. According to statistics, from 1997 to 2017, there have been more than 50 outbreaks of P. spherical algae blooms along the coast of my country, covering a total area of ​​more than 10,000 km 2 The red tide of P. sphericalis poses a huge threat to offshore aquaculture, tourism, cold source safety of coastal power plants and the health of the ecosystem. Therefore, it is urgent to find an environmentally friendly treatment method that can both efficiently remove algae and purify water.

[0003] Currently known red tide control technologies include physical, chemical and biological approaches. Physical methods include common ultrasonic methods, flocculation methods, filtration methods, adsorption methods, etc., which are characterized by simple methods and no secondary pollution, but unstable removal rates. The chemical method is to eliminate red tide algae by adding chemical reagents such as algaecides and algaecides. Its removal is efficient and effective, but it will cause secondary pollution of the water body. The biological method mainly controls red tides by cultivating some biological species such as bacteria and viruses that can specifically remove red tide algae, but there are problems such as slow results and limited effects.

[0004] Ultrasonic control of red tide algae mainly relies on the effect of sound energy on algae cells, inactivating algae cells through mechanical damage or chemical oxidation damage. Because of its simple operation, cost-effectiveness and high efficiency, the effective control of various red tide algae species including cyanobacteria by ultrasonic technology has been widely confirmed in laboratory research and field applications, but there are still some limitations. For example, ultrasound has a good immediate inhibition on red tide algae, but algae cells that are not completely inactivated are easy to recover. In addition, after ultrasound mechanically damages algae cells, it will lead to the release of intracellular toxins, thereby endangering the water environment and other biological safety. Therefore, the development of an environmentally friendly method that can effectively kill red tide algae and make it difficult to recover, while not endangering the health of water bodies, is the key to fundamentally controlling the spherical brown cystis red tide. Summary of the invention

[0005] Aiming at the problems existing in the existing P. spherical algae red tide control technology, the present invention provides a method for controlling the P. spherical algae red tide by combining gel microsphere adsorption and ultrasound, thereby achieving efficient red tide control, preventing recovery and secondary pollution of water bodies.

[0006] The object of the present invention is achieved by providing a method for controlling the red tide of spherical brown algae by combining gel microsphere adsorption and ultrasound, characterized in that the gel microspheres for adsorption control are first prepared, and then the gel microspheres are placed in a filter bag and combined with an ultrasonic device to control the red tide of spherical brown algae in the water area.

[0007] The method for treating the red tide of P. sphericalis by combining gel microsphere adsorption and ultrasound of the present invention can not only efficiently remove the P. sphericalis cells in the water body through the adsorption of gel microspheres and the assistance of ultrasound, but also avoid the release of intracellular hemolytic toxins. At the same time, it also has a good effect of eliminating phosphates in the water body, avoiding the recovery and re-outbreak of red tide algae cells; at the same time, the gel microspheres are placed in the filter bag during use, and when adsorbed and treated in the water body, the adsorption effect is not affected, and it is easy to recycle and reuse after use, has no adverse effect on the water body, and can keep the water body clean.

[0008] In order to facilitate adsorption and treatment, the preparation method of the gel microspheres is as follows: injecting a mixed aqueous solution of sodium alginate and sodium humate into a ferric chloride solution for solidification for 10-15 hours, filtering out the microspheres and burning them at 380-400°C for at least 1 hour to obtain gel microspheres. The gel microspheres obtained by this method have good stability, not only have strong algae removal ability and are environmentally friendly, but also have a good effect on eliminating phosphates in water bodies, and are an effective material for multi-element red tide control.

[0009] Furthermore, the particle size of the gel microspheres is 0.5-1.0 mm, and the pore size of the filter bag is 8-10 μm.

[0010] Furthermore, the mass ratio of the sodium alginate to the sodium humate is 1:1, and the mass concentrations of the sodium alginate and the sodium humate in the mixed aqueous solution are both 1-2%; and the concentration of the ferric chloride solution is 0.05-0.1 M.

[0011] In order to further facilitate the thorough treatment of spherical brown algae, the gel microspheres are placed in filter bags and used in conjunction with ultrasonic devices to treat spherical brown algae red tides in waters. The amount of gel microspheres used per cubic meter of water is 0.22-2.2 kg, and the treatment is carried out in conjunction with ultrasound until the phosphate content in the water is less than 1 ug / L.

[0012] Furthermore, the frequency of the low-frequency ultrasonic treatment is 20-40 kHz.

[0013] The Fe in the gel microspheres of the present invention 3+It can quickly catalyze ultrasonic cavitation to produce hydroxyl radicals, which can not only improve the removal efficiency of spherical brown algae cells, but also degrade the hemolytic toxins in its cells. Secondly, the gel microspheres can also continuously absorb phosphates in the water to prevent the unkilled spherical brown algae from reviving and forming algal blooms. After testing, the number of algal cells, chlorophyll a content and algal toxin content of spherical brown algae decreased significantly after adsorption treatment with gel microspheres. At the same time, the gel microspheres can effectively prevent the resurgence of spherical brown algae by absorbing phosphates in the water.

[0014] Another object of the present invention is to provide a regeneration method for the above-mentioned gel microspheres, characterized in that the gel microspheres after the joint control of the spherical brown algae red tide are placed in distilled water, treated at a pressure of 0.2 MPa and a temperature of 121°C for 20-30 min, and then taken out and dried at 60°C to complete the regeneration of the gel microspheres.

[0015] After the gel microspheres of the present invention are used for adsorption, they are regenerated under the above pressure and temperature conditions, and the killing and anti-resuscitation performances of the spherical brown cysts algae are still good when they are reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 These are the gel microspheres and gel microsphere filter bags prepared in Examples 1 and 2.

[0017] Figure 2 The results of Examples 1 and 2 and Comparative Example 1 are compared in terms of the number of cells, chlorophyll a and removal of hemolytic toxins of Phaeocystis sphericalensis.

[0018] Figure 3 The results of Examples 1 and 2 and Comparative Example 1 are comparative results of the recovery of the cell number, chlorophyll a and hemolytic toxin of Phaeocystis sphericalensis, and the removal of phosphate in the algae liquid.

[0019] Figure 4 The results of the comparison of the cell number, chlorophyll a and hemolytic toxin removal of Phaeocystis sphericalensis by Examples 1 and 2 and Comparative Example 1 after the gel microspheres were regenerated and reused are shown.

[0020] Figure 5 The results of Examples 1 and 2 and Comparative Example 1 after the gel microspheres were regenerated and reused were compared on the cell number, chlorophyll a and hemolytic toxin recovery of Phaeocystis sphericalensis, as well as the removal of phosphate in the algae solution. DETAILED DESCRIPTION Example 1

[0021] Weigh 2 g of sodium alginate and dissolve it in 200 mL of distilled water to obtain a 1 wt % mixed solution. Afterwards, the mixed solution (200 mL) was dripped into a 0.1 M ferric chloride solution (300 mL) using a syringe and solidified for 12 h. Finally, after calcining at 400 °C for 2 h, gel microspheres were prepared. Weigh 0.04 g of gel microspheres and put them into a small bag made of sieve silk with a pore size of 10 μm to prepare a gel microsphere filter bag. The actual camera pictures of the gel microspheres and gel microsphere filter bags prepared in this embodiment are shown in the figure. Figure 1 shown.

[0022] The gel microsphere filter bag was placed in a container containing 25 mL of Phaeocystis sphericalis liquid (cell density was 1×10 4 The cells were placed in a glass test tube with a volume of 100 μg / mL and 1‰ f / 2 culture medium was added for low-frequency ultrasonic treatment. The ultrasonic treatment conditions were: ultrasonic frequency 20 kHz, ultrasonic intensity 180 W, and ultrasonic time 8 min.

[0023] In order to test the anti-resuscitation effect of the above-mentioned gel microsphere adsorption and ultrasound combined treatment on the spherical cyst, the spherical cyst was cultured under light for 7 days after the combined ultrasound treatment. The culture temperature was 25 ℃, the light intensity was 4000 Lux, and the light-dark ratio was 12 h:12 h, and then the physiological activity after recovery was detected.

[0024] In order to further verify the regeneration and reuse performance of the gel microspheres after adsorption, the gel microsphere filter bag was fished out of the spherical brown algae liquid, immersed in distilled water, digested at high temperature and high pressure (121 ℃, 0.2 MPa) for 20 min, and then dried at 60 ℃. The gel microsphere filter bag was then put back into the spherical brown algae liquid of the initial test for secondary utilization. The test conditions were the same as above to test its removal and anti-resuscitation effects on spherical brown algae. Example 2

[0025] The only difference between Example 2 and Example 1 is that sodium humate is added during the preparation of the gel microspheres. Weigh 2 g of sodium alginate and 2 g of sodium humate, and dissolve them in 200 mL of distilled water to obtain a 1 wt % sodium alginate solution. Afterwards, the mixed solution (200 mL) is dripped into a 0.1 M ferric chloride solution (300 mL) with a syringe and solidified for 12 h. Finally, after calcining at 400 °C for 2 h, gel microspheres are prepared. Weigh 0.04 g of gel microspheres and put them into a small bag made of sieve silk with a pore size of 10 μm to make a gel microsphere filter bag. The actual camera pictures of the gel microspheres and gel microsphere filter bags prepared in this example are shown in the figure. Figure 1 As shown, compared with the gel microspheres of Example 1, the difference is that sodium humate is added during the preparation process.

[0026] The gel microsphere filter bag was placed in a container containing 25 mL of Phaeocystis sphericalis liquid (cell density was 1×10 4 The cells were placed in a glass test tube with a volume of 100 μg / mL and 1‰ f / 2 culture medium was added for low-frequency ultrasonic treatment. The ultrasonic treatment conditions were: ultrasonic frequency 20 kHz, ultrasonic intensity 180 W, and ultrasonic time 8 min.

[0027] In order to test the anti-resuscitation effect of the spherical cystalgae treated with the gel microsphere adsorption and ultrasound in this example, the spherical cystalgae liquid treated with the gel microsphere adsorption and ultrasound was restored and cultured for 7 days under light. The culture temperature was 25 ° C, the light intensity was 4000 Lux, and the light-dark ratio was 12 h:12 h.

[0028] In order to test the regeneration of the gel microspheres after use and verify the performance of reuse after regeneration, the gel microsphere filter bag added to the spherical brown cyst algae liquid was fished out, placed in distilled water, digested at high temperature and high pressure (121 ℃, 0.2 Mpa) for 20 minutes, and dried at 60 ℃ to complete the regeneration process. Then the regenerated gel microsphere filter bag was put back into the spherical brown cyst algae liquid for secondary use, and the test conditions were the same as above to test its removal and anti-resuscitation effect on spherical brown cyst algae.

[0029] Comparative Example 1 This comparative example refers to the process of Examples 1 to 2, except that: no gel microsphere filter bag is added, and only 20kHz low-frequency ultrasound is used to treat the spherical Phaeocystis algae liquid. Under the same conditions, the cell number, chlorophyll a content, and hemolytic toxin content of the spherical Phaeocystis algae in the algae liquid under ultrasound treatment are measured, as well as the cell number, chlorophyll a content, hemolytic toxin content, and phosphate content of the spherical Phaeocystis algae after 7 days of recovery culture.

[0030] The removal effect of the spherical cystis algae liquid of the above examples 1 to 2 and comparative example 1 was measured. The number of cells, chlorophyll a content and hemolytic toxin content of the spherical cystis algae in the algae liquid were measured respectively. The measurement results are as follows: Figure 2 shown.

[0031] like Figure 2 a is the measurement result of the number of spherical Phaeocystis algae cells in Examples 1-2 and Comparative Example 1. It shows that the gel microsphere filter bags in Examples 1 and 2 can eliminate spherical Phaeocystis algae cells more efficiently and quickly under the assistance of ultrasound, and the removal rate reaches 50% at the first minute after the reaction begins, and the removal rate at each measuring time is higher than that of Comparative Example 1, indicating that the algae removal method provided by the present invention has obvious advantages, and the gel microsphere filter bag prepared in Example 2 has a better removal effect on spherical Phaeocystis algae cells, and no spherical Phaeocystis algae cells can be observed at the 8th minute.

[0032] like Figure 2b is the measurement result of chlorophyll a of P. sphericalis in Examples 1-2 and Comparative Example 1 at the 8th minute. It also shows that the gel microsphere filter bags in Examples 1 and 2 can more efficiently eliminate P. sphericalis algae cells, and the chlorophyll a content in Example 2 is slightly lower than that in Example 1, which means that the gel microsphere filter bag prepared in Example 2 has the best removal effect on P. sphericalis.

[0033] like Figure 2 c is the measurement result of the hemolytic toxin in the algae liquid of P. sphericalis in Examples 1-2 and Comparative Example 1 at the 8th minute. It also shows that the gel microsphere filter bags in Examples 1 and 2 can more efficiently reduce the content of hemolytic toxins in the water body, and the inactivation effect of Example 2 is higher than that of Example 1, which indicates that the gel microsphere filter bag prepared in Example 2 has the best removal effect on the cytotoxins of P. sphericalis.

[0034] The recovery culture of the algae solution of the above-mentioned Examples 1-2 and Comparative Example 1 was measured. The cell number, chlorophyll a content, hemolytic toxin content and phosphate content of the algae solution were measured respectively. The measurement results are as follows: Figure 3 shown.

[0035] like Figure 3 a is the measurement result of the number of algae cells of P. sphericalis in Examples 1-2 and Comparative Example 1. It shows that the cells of P. sphericalis in Comparative Example 1 have resumed growth after 7 days of light culture. However, the P. sphericalis in Examples 1 and 2 have not resumed growth, and the number of cells is still low. Therefore, both Examples 1 and 2 can inhibit the recovery of red tide of P. sphericalis, and the effect of Example 2 is better than that of Example 1.

[0036] like Figure 3 b is the measurement result of chlorophyll a of spherical Phaeocystis in Examples 1-2 and Comparative Example 1. It also shows that the chlorophyll a content of spherical Phaeocystis in Comparative Example 1 has recovered after 7 days of light culture. However, the chlorophyll a of spherical Phaeocystis in Examples 1 and 2 is still low, which shows that both Examples 1 and 2 can inhibit the recovery of red tide of spherical Phaeocystis, and the effect of Example 2 is better than that of Example 1.

[0037] like Figure 3 c is the measurement result of the hemolytic toxin of P. sphericalensis in Examples 1-2 and Comparative Example 1. It also shows that the hemolytic toxin content of P. sphericalensis in Comparative Example 1 has recovered after 7 days of light culture. However, the hemolytic toxin content of P. sphericalensis in Examples 1 and 2 is still significantly lower than that in Comparative Example 1, which shows that both Examples 1 and 2 can inhibit the recovery of red tide of P. sphericalensis, and the effect of Example 2 is better than that of Example 1.

[0038] like Figure 3d is the measurement result of the phosphate content in the algae liquid in Examples 1-2 and Comparative Example 1. The phosphate content in Examples 1 and 2 is significantly lower than that in Comparative Example 1, and the phosphate content in Example 2 is the lowest. This shows that both Examples 1 and 2 can prevent the resurgence of the red tide of P. sphericalis by absorbing phosphate in the water body, and Example 2 has the best effect.

[0039] The removal effect of the algae liquid of Examples 1-2 and Comparative Example 1 of the microsphere gel regeneration and reuse was measured. The number of cells, chlorophyll a content and hemolytic toxin content of the algae liquid were measured. The measurement results are as follows: Figure 4 shown.

[0040] like Figure 4 a is the measurement result of the number of algae cells of P. spherical in the regenerated and reused Examples 1-2 and Comparative Example 1. It shows that the regenerated and reused gel microsphere filter bag can still efficiently eliminate the algae cells of P. spherical, and the number of algae cells in Example 2 is lower than that in Example 1, and is more obviously lower than that in Comparative Example 1. It shows that the gel microsphere filter bag in Example 2 provided by the present invention has good recycling and can be repeatedly used to eliminate P. spherical.

[0041] like Figure 4 b is the measurement result of chlorophyll a of Pseudocystis spherica in the regenerated and reused Examples 1-2 and Comparative Example 1. It shows that the recycled gel microsphere filter bag can still effectively reduce the chlorophyll a content of Pseudocystis spherica. The chlorophyll a in Example 2 is lower than that in Example 1, and is more obviously lower than that in Comparative Example 1. It shows that the gel microsphere filter bag in Example 2 provided by the present invention has good recycling and can be repeatedly used to eliminate Pseudocystis spherica.

[0042] like Figure 4 c is the measurement result of the hemolytic toxin of P. sphericalis in the regenerated and reused Examples 1-2 and Comparative Example 1. It shows that the regenerated and reused gel microsphere filter bag can still effectively reduce the hemolytic toxin of P. sphericalis, and the hemolytic toxin content in Example 2 is slightly lower than that in Example 1, and more significantly lower than that in Comparative Example 1. It shows that the gel microsphere filter bag in Example 2 provided by the present invention has good recycling and can be repeatedly used to eliminate P. sphericalis.

[0043] The recovery culture of the regenerated and reused P. sphericalis algae liquids of Examples 1 to 2 and Comparative Example 1 was measured. The cell number, chlorophyll a content, hemolytic toxin content, and phosphate content of the P. sphericalis algae in the algae liquid were measured respectively. The measurement results are as follows: Figure 5 shown.

[0044] like Figure 5a is the measurement result of the number of algae cells of P. sphericalis in regenerated and reused Examples 1-2 and Comparative Example 1. It shows that after 7 days of light culture, the cells of P. sphericalis in Comparative Example 1 have resumed growth. However, the regenerated and reused gel microsphere filter bag still significantly inhibited the growth of P. sphericalis in Examples 1-2, and the number of cells was still low, and almost no algae cells were seen in Example 2. Therefore, the gel microsphere filter bag provided by the present invention has good recycling performance, and the effect of Example 2 is better than that of Example 1, and both can inhibit the recovery of red tide of P. sphericalis.

[0045] like Figure 5 b is the measurement results of chlorophyll a of Pseudocystis spherica in the regenerated and reused Examples 1-2 and Comparative Example 1. It shows that after 7 days of light culture, the chlorophyll a of Pseudocystis spherica in Comparative Example 1 has recovered to the initial level. However, the regenerated and reused gel microsphere filter bag still significantly inhibits Pseudocystis spherica in Examples 1-2, and the chlorophyll a content is still low. Therefore, the gel microsphere filter bag provided by the present invention has good recycling performance, and the effect of Example 2 is better than that of Example 1, and both can inhibit the recovery of red tide of Pseudocystis spherica.

[0046] like Figure 5 c is the measurement result of the hemolytic toxin of P. sphericalensis in the regenerated and reused Examples 1-2 and Comparative Example 1. It shows that the hemolytic toxin of P. sphericalensis in Comparative Example 1 has gradually recovered after 7 days of light culture. The regenerated and reused gel microsphere filter bag still significantly inhibits P. sphericalensis in Examples 1-2, and the hemolytic toxin content is still low. Therefore, the gel microsphere filter bag provided by the present invention has good recycling performance, and the effect of Example 2 is better than that of Example 1, and both can inhibit the recovery of the red tide of P. sphericalensis.

[0047] like Figure 5 d is the measurement result of phosphate in the algae solution in the regenerated and reused Examples 1-2 and Comparative Example 1. The phosphate content of the regenerated and reused gel microsphere filter bag in Examples 1 and 2 is significantly lower than that in Comparative Example 1, and the phosphate content in Example 2 is the lowest. This shows that the regenerated and reused gel microsphere filter bag still has good adsorption performance for phosphate, and can prevent the resurgence of the red tide of P. sphericalis by reducing the phosphate in the water body, and Example 2 has the best effect.

[0048] In summary, the present invention provides a method for controlling the red tide of spherical brown algae by combining gel microsphere adsorption and ultrasound, and a method for regenerating gel microspheres, which is simple and easy to operate, can not only efficiently kill spherical brown algae cells and degrade hemolytic toxins, but also has a good adsorption effect on phosphates in water bodies, avoiding the recovery and re-outbreak of red tide algae cells, and the gel microspheres can be recycled for regeneration and reuse, and the reuse effect is still good. Therefore, the method of combining gel microsphere adsorption and ultrasound to control the red tide of spherical brown algae of the present invention is a simple, efficient, and environmentally friendly new method for controlling red tides.

Claims

1. A method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound, characterized in that: Firstly, gel microspheres for adsorption treatment are prepared, and then the gel microspheres are placed in a filter bag and combined with an ultrasonic device to treat the red tide of spherical brown cysts in the water area.

2. The method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound according to claim 1, characterized in that: The preparation method of the gel microspheres is as follows: injecting a mixed aqueous solution of sodium alginate and sodium humate into a ferric chloride solution for solidification for 10-15 hours, filtering out the microspheres and calcining them at 380-400°C for at least 1 hour to obtain the gel microspheres.

3. The method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound according to claim 2, characterized in that: The particle size of the gel microspheres is 0.5-1.0 mm, and the pore size of the filter bag is 8-10 μm.

4. The method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound according to claim 2, characterized in that: The mass ratio of the sodium alginate to the sodium humate is 1:1, and the mass concentrations of the sodium alginate and the sodium humate in the mixed aqueous solution are both 1-2%; the concentration of the ferric chloride solution is 0.05-0.1 M.

5. The method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound according to claim 1, characterized in that: When gel microspheres are placed in filter bags and used in conjunction with ultrasonic devices to control red tides caused by Pseudocystis spherica in waters, the amount of gel microspheres used per cubic meter of water is 0.22-2.2 kg, and low-frequency ultrasound is used for combined control until the phosphate content in the water is less than 1 ug / L.

6. The method for controlling red tide of Phaeocystis sphericalensis by combining gel microsphere adsorption and ultrasound according to claim 5, characterized in that: The frequency of the low-frequency ultrasonic treatment is 20-40 kHz.

7. A method for regenerating gel microspheres according to any one of claims 1 to 5, characterized in that: The gel microspheres after combined treatment were placed in distilled water, treated at a pressure of 0.2 MPa and a temperature of 121°C for 20-30 min, and then taken out and dried at 60°C to complete the regeneration of the gel microspheres.

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