CN104787902A - Method for adsorbing heavy metal in wastewater by using mold spore - Google Patents

Abstract

A method for using mold spores to adsorb heavy metals in wastewater, which relates to a method for using mold spores to adsorb heavy metals in wastewater. The present invention aims to solve the problems of poor adsorption effect and high cost of existing mold mycelium ball powder adsorbents. The present invention The inventive method is as follows: 1. Inoculate the mold spores on the solid medium, cultivate them at 30°C, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold; 2. Add the mold spores collected in step 1 to the In wastewater containing heavy metals, it is completed; the advantage of the invention is that the collection of spores can simplify the preparation steps of the adsorbent, save costs and increase the adsorption capacity of heavy metals at the same time. The invention is applied in the field of adsorbents.

Description

A method of using mold spores to adsorb heavy metals in wastewater

technical field

The invention relates to a method for adsorbing heavy metals in waste water.

Background technique

Traditional heavy metal removal technology: The traditional methods for the removal of heavy metals include chemical precipitation, redox, ion exchange, electrochemical treatment, filtration, reverse osmosis, solvent extraction and evaporation recovery. Various physical and chemical methods are only the transfer, concentration, or change of the form of heavy metal ions. Heavy metals will not disappear and the total amount will not decrease. This is what distinguishes heavy metal wastewater from other wastewater. In the early years, the ion exchange method was widely used, but due to the high cost of the resin, there are certain restrictions on the original water quality, such as organic matter and oxides in the wastewater will cause the resin to fail, so the chemical method followed. , electrolysis, etc. have gradually appeared and been applied. The disadvantage of the chemical method is that it occupies a large area and produces sludge containing heavy metals. The sludge has not been properly treated, so there is a problem of secondary pollution. The disadvantage of the electrolysis method is that it consumes a lot of electricity, and the use effect is not ideal when the content of heavy metals is high. The electrolysis method is often used for the recovery of precious metals, but for metals with low recovery value, such as copper, the loss outweighs the gain. Environmental workers have long proposed that it is possible to use biological methods to remove heavy metals, and have conducted research for many years. What is widely used at present is to inoculate the bacteria into the liquid culture medium. Under the culture conditions of certain temperature and rotating speed, the mycelial balls are cultivated in the shaking flask, and then washed, filtered, dried, ground and sieved before being washed. As an available adsorbent, although it is green and environmentally friendly, its cumbersome operation steps, expensive medium costs and harsh culture conditions make it difficult to realize industrialization.

Contents of the invention

The purpose of the present invention is to solve the problems of poor adsorption effect and high cost of the existing mold mycelium ball powder adsorbent, and provide a method for using mold spores to adsorb heavy metals in waste water.

A method of utilizing mold spores to adsorb heavy metals in waste water of the present invention is prepared according to the following steps:

1. Inoculate the mold spores on a solid medium, cultivate them at 29-31°C, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold;

2. Add the mold spores collected in step 1 to the wastewater containing heavy metals, then stir at a temperature of 10-40°C, and complete the adsorption for 1.5-2.5 hours; the mold is Aspergillus niger with strain number 98003 ; The mass volume ratio of mold spores to wastewater containing heavy metals is 1: (900-1100) g/mL.

The invention has the advantages that the collection of spores can simplify the preparation steps of the adsorbent, save the cost and increase the heavy metal adsorption capacity at the same time. The spore is the fungus that propagates from the differentiated aerial hyphae in the late stage of growth on the surface of the solid medium, and it can fall off by itself after about 7 days. The spore is a dormant body with strong stress resistance, and its resistance to physical, chemical and drug effects It is very strong, so the cell wall is not easily damaged even during the adsorption process. At the same time, the diameter of the spore is very small, about 2um, so it has a large specific surface area.

Detailed ways

Specific embodiment one: In this embodiment, a method for utilizing mold spores to adsorb heavy metals in wastewater is prepared according to the following steps:

1. Inoculate the mold spores on a solid medium, cultivate them at 29-31°C, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold;

2. Add the mold spores collected in step 1 to the wastewater containing heavy metals, then stir at a temperature of 10-40°C, and complete the adsorption for 1.5-2.5 hours; the quality of mold spores and wastewater containing heavy metals The volume ratio is 1: (900~1100) g/mL.

The mold in this embodiment is Aspergillus niger with strain number 98003, purchased from Harbin Chunrui Technology Development Co., Ltd.

The advantage of this embodiment is that the collection of spores can simplify the preparation steps of the adsorbent, save costs and increase the adsorption capacity of heavy metals.

Specific embodiment two: the difference between this embodiment and specific embodiment one is: the mold is Aspergillus niger (Aspergillus niger) with strain number 98003. Others are the same as the first embodiment.

Specific embodiment three: the difference between this embodiment and specific embodiment one or two is that: the solid medium described in step one is improved Martin medium, PDA medium or dry rice straw medium. Others are the same as those in Embodiment 1 or 2.

The present embodiment improves Martin medium: peptone 5.0g, dipotassium hydrogen phosphate 1.0g, yeast extract powder 2.0g, magnesium sulfate 0.5g, glucose 20.0g, agar powder 15g, water 1000ml, ph6.4;

PDA medium: 200g peeled potatoes, boiled in water for 30min, supplemented with 1000ml of distilled water, added 20g of glucose, 15g of agar powder;

Dry straw medium: Grind dry straw through a 60-mesh sieve, and add water at a mass-volume ratio of 1:1.

Embodiment 4: This embodiment differs from Embodiment 1 to Embodiment 3 in that: the heavy metal copper described in step 2. Other steps and parameters are the same as those in the first to third specific embodiments.

Embodiment 5: This embodiment is different from Embodiment 1 to Embodiment 4 in that: Stirring is carried out at a temperature of 30° C. as described in Step 2. Other steps and parameters are the same as one of the specific embodiments 1 to 4.

Embodiment 6: This embodiment differs from Embodiment 1 to Embodiment 5 in that: the stirring speed in step 2 is 0-300 rpm. Other steps and parameters are the same as one of the specific embodiments 1 to 5.

Embodiment 7: The difference between this embodiment and one of Embodiments 1 to 6 is that the adsorption time is 2 hours. Other steps and parameters are the same as one of the specific embodiments 1 to 6.

Prove the beneficial effect of the present invention by following test:

Test 1, the method that this test test group utilizes mold spores to adsorb heavy metals in wastewater is prepared according to the following steps:

1. Inoculate the mold spores on the improved Martin medium, culture them at 30°C for 6-7 days, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold;

2. Add the mold spores collected in step 1 to the wastewater with a copper content of 30mg/L, and then stir at a temperature of 30°C at a stirring speed of 100rmp, and the adsorption is complete for 2 hours; the specific strain of the mold Name and Latin; the mass volume ratio of mold spores to copper-containing wastewater is 1:1000g/mL.

The adsorption capacity of spores in the test group was 27.2 mg/g.

In the control group, the mold mycelium ball powder adsorbent was added to the wastewater with a copper content of 30mg/L, and then stirred at a temperature of 30°C, the stirring speed was 100rmp, and the adsorption was completed for 2 hours; the specific content of the mold Strain name and Latin; the mass volume ratio of mold mycelium ball powder adsorbent to heavy copper-containing wastewater is 1:1000g/mL.

The preparation method of the mold mycelium ball powder adsorbent is as follows: inoculate the mold into the liquid medium, and under the culture conditions of 30°C and the rotation speed of 100rmp, shake the flask to cultivate the mycelium ball, and then wash, filter, and dry , after grinding and sieving, the mold mycelia ball powder adsorbent is obtained. The adsorption capacity of the mold mycelium ball powder adsorbent in the control group was 5.7 mg/g.

The experimental group can simplify the preparation steps of the adsorbent, save the cost and increase the adsorption capacity of heavy metals at the same time.

Test 2, the method that this test test group utilizes mold spores to adsorb heavy metals in wastewater is prepared according to the following steps:

1. Inoculate the mold spores on the improved Martin medium, culture them at 30°C for 7 days, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold;

2. Add the mold spores collected in step 1 to the wastewater with a copper content of 30mg/L, and then perform adsorption at a temperature of 30°C for 2 hours, and the stirring speed is 0rmp, which is completed; the specific strain of the mold Name and Latin; the mass volume ratio of mold spores to copper-containing wastewater is 1:1000g/mL.

The adsorption capacity of spores in the test group was 24.5 mg/g.

The mold in Tests 1-2 was Aspergillus niger with strain number 98003, which was purchased from Harbin Chunrui Technology Development Co., Ltd.

Claims (7)

1. a method utilizing the heavy metal in the mold spore adsorption waste water is characterized in that utilizing the method for the heavy metal in the mold spore adsorption waste water is prepared according to the following steps: 1. Inoculate the mold spores on a solid medium, cultivate them at 29-31°C, and then collect the mold spores that naturally fall off from the aerial hyphae of the mold; 2. Add the mold spores collected in step 1 to the wastewater containing heavy metals, then stir at a temperature of 10-40°C, and complete the adsorption for 1.5-2.5 hours; the quality of mold spores and wastewater containing heavy metals The volume ratio is 1: (900~1100) g/mL. 2. A method for utilizing mold spores to adsorb heavy metals in waste water according to claim 1, characterized in that said mold is Aspergillus niger of bacterial strain number 98003. 3. A method for utilizing mold spores to adsorb heavy metals in waste water according to claim 1, characterized in that the solid medium described in step 1 is an improved Martin medium, PDA medium or dry straw medium. 4. A method for utilizing mold spores to adsorb heavy metals in waste water according to claim 1, characterized in that the heavy metals described in step 2 are copper. 5. A method of utilizing mold spores to adsorb heavy metals in wastewater according to claim 1, characterized in that the stirring is carried out at a temperature of 30°C as described in step 2. 6. A method of utilizing mold spores to adsorb heavy metals in wastewater according to claim 1, characterized in that the stirring speed in step 2 is 0-300rmp. 7. A method for utilizing mold spores to adsorb heavy metals in waste water according to claim 1, characterized in that the adsorption time described in step 2 is 2 hours.