CN105624095B

CN105624095B - Method for enrichment culture of nitrifying bacteria by utilizing wastewater generated in catalyst production process

Info

Publication number: CN105624095B
Application number: CN201410585589.6A
Authority: CN
Inventors: 高会杰; 孙丹凤; 郭志华; 赵胜楠
Original assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Priority date: 2014-10-28
Filing date: 2014-10-28
Publication date: 2020-06-05
Anticipated expiration: 2034-10-28
Also published as: CN105624095A

Abstract

The invention discloses a method for enrichment culture of nitrobacteria by utilizing wastewater generated in a catalyst production process, which comprises the steps of firstly selecting activated sludge rich in nitrobacteria as inoculated sludge, adopting ammonia-containing wastewater generated in the catalyst production process as a culture solution, adopting a mode of changing water in batches and gradually increasing the ammonia nitrogen concentration of a matrix for culture, supplementing a nitrobacteria growth promoter while changing the culture solution each time, wherein the nitrobacteria growth promoter comprises 40-100 parts by weight of metal salt and polyamine substances, preferably 50-80 parts by weight of metal salt, and 5-30 parts by weight of polyamine substances, preferably 10-20 parts by weight; the metal salt is composed of calcium salt, copper salt, magnesium salt and/or ferrous salt. The invention takes industrial wastewater as culture solution and adopts a mode of adding growth promoter to carry out enrichment culture on nitrobacteria, so that nitrobacteria with strong tolerance can rapidly grow and propagate in a short time, and ammonia nitrogen in the wastewater can be efficiently degraded under the condition of high salinity.

Description

Method for enrichment culture of nitrifying bacteria by utilizing wastewater generated in catalyst production process

Technical Field

The invention belongs to the technical field of biology, and particularly relates to a method for enrichment culture of nitrifying bacteria by utilizing wastewater generated in a catalyst production process.

Background

In the biological denitrification method, ammonia nitrogen is removed by nitrification of nitrifying bacteria in both traditional nitrification-denitrification, novel shortcut nitrification-denitrification and novel shortcut nitrification-anaerobic ammonia oxidation. Nitrification bacteria belong to the group of energy-producing nutritional microorganisms. Biological cells can utilize only energy stored in the form of ATP or the like, and cannot directly utilize free energy released by chemical reaction. In aerobic metabolism, ATP is synthesized mainly by oxidative phosphorylation of the respiratory chain. The ammoxidation phosphorylation efficiency is very low, the ATP generated by the ammoxidation phosphorylation is very limited, and the energy is mainly used for electron transition to a higher energy level, so that the nitrobacteria grow very slowly, and the generation period is 8-36 h. The content of peptidoglycan in the cell wall of nitrobacteria is low, and the content of protein and fat is high, so that the nitrobacteria is sensitive to environmental change, the adaptability and tolerance of natural nitrobacteria in nature are poor, and the nitrobacteria cannot compete with heterotrophic microorganisms in growth under a plurality of conditions to obtain advantages. In a sewage treatment system, when the content of nitrifying bacteria in activated sludge is low, the nitrifying bacteria cannot grow and propagate quickly in a short time by adjusting the environmental conditions such as dissolved oxygen, pH and the like, and finally the ammonia nitrogen removal capability of the existing running sewage treatment system is limited. No matter nitrifying bacteria are cultured in the sewage treatment system directly or outside the sewage treatment system, substances for promoting growth need to be added to accelerate the growth rate of the nitrifying bacteria.

Chinese patents CN200510111874.5, CN200510111876.4, CN200510111877.9 and cn200510111875.x respectively propose nitrobacteria growth promoters composed of different metal salts, the main components of which include molasses, metal salts (iron salt, manganese salt, calcium salt and magnesium salt) and adsorbent. The ammonia nitrogen removal rate can be improved by more than 20 percent after the accelerator is used. However, the addition of the adsorbents mainly comprises substances such as zeolite powder, diatomite, powdered activated carbon or fly ash and the like, which inevitably increases the sludge yield. Chinese patent CN200710010383.0 discloses a method for enriching efficient nitrifying bacteria in activated sludge, which adopts an intermittent activated sludge method and carries out enrichment by gradually increasing the ammonia nitrogen concentration of a culture solution; chinese patent CN201010221166.8 discloses a method for culturing nitrosation dominant flora, which adopts three optimization stages for culture. The invention adopts a mode of adding ammonium salt to prepare the culture solution, which additionally increases the culture cost of the denitrifying microorganisms.

CN1354786A discloses a method for culturing high-concentration nitrifying bacteria in activated sludge, which is characterized in that sewage sludge and feces and urine sludge are used as inoculated sludge, sludge dewatering filtrate or nitrification release liquid is used as culture solution, the ammonia nitrogen concentration is 100-300 mg/L, the ammonia nitrogen concentration is higher than 300mg/L, the growth of bacteria can be inhibited, and the enriched nitrifying bacteria cannot tolerate the high-concentration ammonia nitrogen. When the nitrifying bacteria obtained by the method are used for treating sewage with ammonia nitrogen concentration higher than 300mg/L, the sewage needs to be diluted to below 300mg/L by seawater or fresh water and then treated.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a method for enriching and culturing nitrobacteria by utilizing wastewater generated in the catalyst production process. The invention takes industrial wastewater as culture solution and adopts a mode of adding growth promoter to carry out enrichment culture on nitrobacteria, so that nitrobacteria with strong tolerance can rapidly grow and propagate in a short time, and ammonia nitrogen in the wastewater can be efficiently degraded under the condition of high salinity.

The invention relates to a method for enriching and culturing nitrobacteria by utilizing wastewater generated in the production process of a catalyst, which comprises the following steps: firstly, selecting activated sludge rich in nitrobacteria as inoculated sludge, adopting ammonia-containing wastewater generated in the catalyst production process as a culture solution, adopting a mode of changing water in batches and gradually increasing the ammonia nitrogen concentration of a substrate for culturing, and supplementing a nitrobacteria growth promoter while changing the culture solution each time, wherein the nitrobacteria growth promoter comprises metal salt and polyamine substances, wherein the metal salt accounts for 40-100 parts by weight, preferably 50-80 parts by weight, and the polyamine substances account for 5-30 parts by weight, preferably 10-20 parts by weight; the metal salt consists of calcium salt, copper salt, magnesium salt and/or ferrous salt; and ending the culture process of one period until the nitrifying bacteria culture solution is completely wastewater generated in the catalyst production process and the ammonia nitrogen removal rate of the culture solution is more than 90% within 24 hours.

The metal salt in the nitrobacteria growth promoter can be calcium salt, magnesium salt and copper salt, wherein Ca²⁺、Mg² ⁺And Cu²⁺The molar ratio of (5-15): (5-25): 0.5-5), preferably (8-12): 10-20): 1-4; or salts of calcium, ferrous and copper, where Ca²⁺、Fe²⁺And Cu²⁺The molar ratio of (5-15): (1-8): 0.5-5), preferably (8-12): 2-6): 1-4; or calcium, magnesium, ferrous and copper salts, of which Ca is present²⁺、Mg²⁺、Fe²⁺And Cu²⁺The molar ratio of (5-15): (5-25): 1-8): 0.5~ (8)5) Preferably (8 to 12), (10 to 20), (2 to 6), (1 to 4).

The calcium salt in the nitrobacteria growth promoter is CaSO₄Or CaCl₂Preferably CaSO₄(ii) a The magnesium salt is MgSO₄Or Mg Cl₂Preferably MgSO (MgSO)₄(ii) a The ferrous salt is FeSO₄Or FeCl₂Preferably FeSO₄(ii) a The copper salt being CuSO₄Or CuCl₂Preferably CuSO₄. The polyamine substance in the nitrobacteria growth promoter is spermine, spermidine or a mixture of spermine and spermidine.

The nitrobacteria growth promoter can also comprise 0.5-15 parts by weight of inorganic hydroxylamine acid, preferably 2-10 parts by weight. The inorganic acid hydroxylamine is one or more of hydroxylamine hydrochloride, hydroxylamine sulfate or hydroxylamine phosphate, and is preferably hydroxylamine sulfate. The appropriate amount of the inorganic hydroxylamine acid can be used as a matrix of hydroxylamine oxidoreductase to directly participate in the metabolic process of nitrobacteria, shorten the enzymatic reaction process, and simultaneously can be used as an activator of cells to accelerate the growth of the cells.

The water quality of the wastewater generated in the catalyst production process is characterized in that: the ammonia nitrogen concentration is generally 300-1000 mg/L, the COD (Cr method, the same below) concentration is 30-200 mg/L, the total salt content is 1-8 ten thousand mg/L, the pH is 7-11, and the salt belongs to alkaline water. The enrichment culture condition of the nitrifying bacteria is that the temperature is 18-40 ℃, and the optimal selection is 25-35 ℃; the dissolved oxygen is 1-5 mg/L, preferably 2-3 mg/L; the pH is 7.0-9.0, preferably 7.8-8.5.

In the enrichment culture process of nitrobacteria, firstly, the catalyst wastewater is diluted by low-ammonia-content wastewater until the ammonia nitrogen concentration is less than 100mg/L to serve as an initial culture solution, and the growth promoter is supplemented while the culture solution is replaced in each batch. The nitrobacteria growth promoter is added according to the concentration of the promoter in a culture system of 10-50 mg/L, preferably 20-40 mg/L, the growth promoter needs to be supplemented when a nitrobacteria culture solution is replaced every time, and the concentration of the promoter is increased by 2-5 mg/L every time the concentration of ammonia nitrogen in the culture solution is increased by 100 mg/L.

Compared with the prior art, the invention has the following beneficial effects:

1. the method utilizes the industrial wastewater as the culture solution and adopts a mode of adding the growth promoter to culture the nitrobacteria, and the cultured nitrobacteria are directly added into the sewage treatment process, so that the method has the advantages of low usage amount, strong impact resistance, good sewage treatment effect and the like. Compared with the prior art, on one hand, the culture cost of nitrobacteria can be reduced, on the other hand, ammonia-containing wastewater generated in the catalyst generation process can be treated while the bacteria are cultured, and economic benefits and social benefits are achieved.

2. According to the invention, the growth promoter with special composition and proportion is supplemented in the enrichment culture process of the nitrifying bacteria, so that the nitrifying bacteria can rapidly grow and propagate in a short time under the combined action of the metal salt, the polyamine substances and the inorganic hydroxylamine acid, the problem of slow growth of the nitrifying bacteria is solved, and the growth rate of the nitrifying bacteria can be increased by 10-100 times after the promoter is used.

3. The growth promoter used in the invention contains metal ions provided by metal salts as elements required by the growth of nitrobacteria, and simultaneously, the metal ions are used as enzyme components to improve the activity of the enzyme, so that substrates can be quickly degraded, and the enzymatic reaction process is accelerated. The polyamine can promote cell proliferation, and can accelerate cell proliferation by coaction with metal ions, improve settleability and stability of the harvested bacteria, and prolong the service life of the bacteria.

Detailed Description

The present invention will be described in detail with reference to specific examples.

EXAMPLE 1 preparation of Nitrobacter growth promoter

The preparation method of the nitrobacteria growth promoter comprises the following steps: (1) preparing a metal salt solution according to the following components in parts by weight: the metal salt is 40-100 parts by weight, preferably 50-80 parts by weight, and the metal salt consists of calcium salt, copper salt, magnesium salt and/or ferrous salt; (2) before use, 5-30 parts by weight, preferably 10-20 parts by weight of polyamine substances are added into the metal salt solution. Furthermore, the inorganic hydroxylamine acid with the content of 0.5-15 parts by weight, preferably 2-10 parts by weight can be added before use.

The four types of nitrobacteria growth promoters are prepared by the method according to the proportion and the formula of the promoters in the table 1, and the concentration of the promoters is 0.5 g/L.

TABLE 1 formulation and proportions of accelerators

EXAMPLE 2 enrichment culture of nitrifying bacteria

Firstly, activated sludge rich in nitrobacteria of a sewage treatment plant is inoculated into five parallel nitrobacteria culture reactors (the reactors are named as No. 1, No. 2, No. 3, No. 4 and No. 5 respectively), and MLSS is 3000mg/L after inoculation. The water quality characteristics of the wastewater produced during the production of the catalyst and the enrichment culture conditions of nitrifying bacteria are shown in Table 2. Firstly, diluting the wastewater until the ammonia nitrogen concentration is 100mg/L to serve as an initial culture solution, wherein the initial accelerator concentration is 20mg/L, the ammonia nitrogen concentration in the culture solution is increased by 50mg/L each time, and the accelerator concentration is increased by 3mg/L each time. No. 5 No promoter was added during the culture as a control. After a period of culture, the enrichment culture process of one period is finished when the culture solution is completely wastewater generated in the catalyst production process and the removal rate of ammonia nitrogen in the culture solution reaches 90% within 24 h. After the completion of the culture, the ammonia nitrogen removal rate is shown in Table 2.

TABLE 2 cultivation conditions and results of nitrifying bacteria

From the data in Table 2, the ammonia nitrogen removal rate of the reactor No. 1-4 after the culture is over 90%, and the ammonia nitrogen removal rate of the reactor No. 5 without the accelerator is only 61.3%. Therefore, the use of the growth promoter can obviously improve the removal rate of the nitrobacteria on the ammonia nitrogen in the wastewater generated in the catalyst production process.

Claims

1. A method for enriching and culturing nitrobacteria by utilizing wastewater generated in the catalyst production process is characterized by comprising the following steps: firstly, selecting activated sludge rich in nitrobacteria as inoculated sludge, and collectingUsing ammonia-containing wastewater generated in the catalyst production process as a culture solution, performing culture in a mode of changing water in batches and gradually increasing the ammonia nitrogen concentration of a matrix, and supplementing a nitrobacteria growth promoter while changing the culture solution each time, wherein the nitrobacteria growth promoter comprises 40-100 parts by weight of metal salt and 5-30 parts by weight of polyamine substance, and the metal salt consists of calcium salt, copper salt, magnesium salt and/or ferrous salt; the polyamine substance is spermine, spermidine or a mixture of spermine and spermidine; ending the culture process of a period until the nitrifying bacteria culture solution is completely wastewater generated in the catalyst production process and the ammonia nitrogen removal rate in the culture solution is more than 90% within 24 hours; the metal salt in the nitrobacteria growth promoter is calcium salt, magnesium salt and copper salt, wherein Ca is²⁺、Mg²⁺And Cu²⁺The molar ratio of (5-15): (5-25): 0.5-5); or salts of calcium, ferrous and copper, where Ca²⁺、Fe²⁺And Cu²⁺The molar ratio of (5-15): (1-8): 0.5-5); or calcium, magnesium, ferrous and copper salts, of which Ca is present²⁺、Mg²⁺、Fe²⁺And Cu²⁺The molar ratio of (5-15): (5-25): (1-8): 0.5-5).

2. The method of claim 1, wherein: the nitrobacteria growth promoter comprises 50-80 parts by weight of metal salt and 10-20 parts by weight of polyamine substance.

3. The method of claim 1, wherein: when the metal salt is a calcium salt, a magnesium salt and a copper salt, Ca²⁺、Mg²⁺And Cu²⁺The molar ratio of (8-12) to (10-20) to (1-4); or calcium, ferrous and copper salts, Ca²⁺、Fe²⁺And Cu²⁺The molar ratio of (8-12) to (2-6) to (1-4); or calcium, magnesium, ferrous and copper salts, Ca²⁺、Mg²⁺、Fe²⁺And Cu²⁺The molar ratio of (8-12): (10-20): (2-6): 1-4).

4. The method of claim 1, wherein: the calcium salt in the nitrobacteria growth promoter is CaSO₄Or CaCl₂(ii) a The magnesium salt is MgSO₄Or MgCl₂(ii) a The ferrous salt is FeSO₄Or FeCl₂(ii) a The copper salt being CuSO₄Or CuCl₂。

5. The method according to claim 1 or 2, characterized in that: the nitrobacteria growth promoter also comprises 0.5-15 parts by weight of inorganic hydroxylamine acid; the inorganic hydroxylamine acid is one or more of hydroxylamine hydrochloride, hydroxylamine sulfate or hydroxylamine phosphate.

6. The method of claim 5, wherein: the content of the inorganic hydroxylamine acid is 2-10 parts by weight.

7. The method of claim 1, wherein: the water quality of the wastewater generated in the catalyst production process is characterized in that: the ammonia nitrogen concentration is 300-1000 mg/L, the COD concentration is 30-200 mg/L, the total salt amount is 1-8 ten thousand mg/L, and the pH is 7-11.

8. The method of claim 1, wherein: the enrichment culture conditions of the nitrifying bacteria are that the temperature is 18-40 ℃, the dissolved oxygen is 1-5 mg/L, and the pH is 7.0-9.0.

9. The method of claim 8, wherein: the enrichment culture conditions of the nitrifying bacteria are that the temperature is 25-35 ℃, the dissolved oxygen is 2-3 mg/L, and the pH is 7.8-8.5.

10. The method of claim 1, wherein: in the enrichment culture process of nitrobacteria, firstly, diluting catalyst wastewater with low-ammonia-content wastewater until the ammonia nitrogen concentration is less than 100mg/L to serve as initial culture solution, replacing the culture solution in each batch, simultaneously replenishing a growth promoter, and replenishing the growth promoter according to the concentration of the promoter in a culture system of 10-50 mg/L.

11. The method according to claim 1 or 10, characterized in that: the nitrobacteria growth promoter is supplemented according to the concentration of the promoter in a culture system of 20-40 mg/L, and the concentration of the promoter is increased by 2-5 mg/L every time the concentration of ammonia nitrogen in a culture solution is increased by 100 mg/L.