CN113402104B - Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater - Google Patents

Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater Download PDF

Info

Publication number
CN113402104B
CN113402104B CN202110482551.6A CN202110482551A CN113402104B CN 113402104 B CN113402104 B CN 113402104B CN 202110482551 A CN202110482551 A CN 202110482551A CN 113402104 B CN113402104 B CN 113402104B
Authority
CN
China
Prior art keywords
wastewater
treatment
sludge
anaerobic
lead
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202110482551.6A
Other languages
Chinese (zh)
Other versions
CN113402104A (en
Inventor
狄国勋
文剑
陈伟军
黄娅
朱兴华
李佳怡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Guangdong Zhongjin Lingnan Environmental Protection Engineering Co ltd
Original Assignee
Guangdong Zhongjin Lingnan Environmental Protection Engineering Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Guangdong Zhongjin Lingnan Environmental Protection Engineering Co ltd filed Critical Guangdong Zhongjin Lingnan Environmental Protection Engineering Co ltd
Priority to CN202110482551.6A priority Critical patent/CN113402104B/en
Publication of CN113402104A publication Critical patent/CN113402104A/en
Application granted granted Critical
Publication of CN113402104B publication Critical patent/CN113402104B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F2001/007—Processes including a sedimentation step
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/101—Sulfur compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/10—Nature of the water, waste water, sewage or sludge to be treated from quarries or from mining activities
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/05—Conductivity or salinity
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/06—Controlling or monitoring parameters in water treatment pH
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/10—Solids, e.g. total solids [TS], total suspended solids [TSS] or volatile solids [VS]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/22—O2
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/44—Time
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/06—Nutrients for stimulating the growth of microorganisms
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/28—Anaerobic digestion processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/28—Anaerobic digestion processes
    • C02F3/2806—Anaerobic processes using solid supports for microorganisms
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/28—Anaerobic digestion processes
    • C02F3/2813—Anaerobic digestion processes using anaerobic contact processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/28—Anaerobic digestion processes
    • C02F3/2846—Anaerobic digestion processes using upflow anaerobic sludge blanket [UASB] reactors
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/32—Biological treatment of water, waste water, or sewage characterised by the animals or plants used, e.g. algae
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Sludge (AREA)
  • Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)

Abstract

The application belongs to the technical field of environmental protection pollutant treatment methods, and particularly relates to a biological treatment method for removing sulfate radicals and COD in lead-zinc beneficiation wastewater, which comprises the following steps: detecting and judging the mass concentration ratio of COD (chemical oxygen demand) to sulfate radical in the lead-zinc mineral separation wastewater, if the mass concentration ratio is less than N, firstly carrying out hydrolytic acidification treatment, then adding alkali liquor to adjust the pH value of the wastewater, and if the mass concentration ratio is equal to N, directly adding alkali liquor to adjust the pH value of the wastewater; carrying out anaerobic treatment to reduce sulfate radicals in the wastewater into hydrogen sulfide; carrying out hydrogen sulfide stripping treatment to remove hydrogen sulfide in the wastewater; carrying out aerobic treatment to remove COD in the wastewater; and (4) performing solid-liquid separation on the wastewater to obtain a water body meeting the sewage discharge standard. The biological treatment method can greatly reduce sulfate radicals, organic pollutants and other substances in the wastewater, so that the effluent reaches the national discharge standard, and has the advantages of low energy consumption, less residual sludge, impact load resistance, convenient operation management, high treatment efficiency, low operation cost, environmental protection and high efficiency.

Description

Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater
Technical Field
The invention belongs to the technology of environmental protection pollutant treatment, and particularly relates to a biological treatment method for removing sulfate radicals and COD in lead-zinc beneficiation wastewater.
Background
The lead-zinc ore dressing process needs a large amount of water, the water quantity used in circulation is removed, and most of wastewater is discharged. Because the beneficiation reagent is required to be added in the beneficiation process, the beneficiation reagent contains a large amount of sulfate, and part of the beneficiation reagent can remain in the wastewater, the discharged wastewater contains a large amount of sulfate radicals and heavy metals, the wastewater has great harm to aquatic ecosystems and human bodies, after the wastewater is discharged into a water body, the toxic substances are many, the water quality is greatly changed, the ecosystems are damaged, and great impact is generated on the environment.
At present, the treatment method for the wastewater containing high-concentration acid mainly comprises an advanced oxidation method, a biological method, an adsorption method, a solvent extraction method and the like; generally, the treatment is carried out by a plurality of pretreatment and biochemical combined processes; the methods for removing COD mainly include physical methods, chemical methods, biological methods, etc. Although the method and the process for separately treating COD and high-concentration sulfate radicals are reported, the treatment process is less and the effect is unstable or not ideal for the lead-zinc beneficiation wastewater containing COD and high-concentration sulfate radicals. In addition, in the beneficiation wastewater, according to the large content range of the sulfate radical in beneficiation, when the production is adjusted or fluctuated, the chemical composition of the beneficiation wastewater also has certain change, the existing method can achieve the efficient and stable removal effect, and the treated water obtained after treatment can reach the beneficiation index, so that the research and development of a simpler, environment-friendly, rapid and efficient method for treating the lead-zinc beneficiation wastewater are urgently needed to solve the current needs.
Disclosure of Invention
Based on the requirements of the field, the invention combines different contents and physicochemical characteristics of COD and high-concentration sulfate radicals in the lead-zinc beneficiation wastewater, and provides a biological treatment method for removing sulfate radicals and COD in the lead-zinc beneficiation wastewater and obtaining treated water which can be reused for beneficiation, and the technical scheme is as follows:
a biological treatment method for removing sulfate radicals and COD in lead-zinc beneficiation wastewater comprises the following steps:
step one, detecting the mass concentration of COD and sulfate radical in lead-zinc mineral processing wastewater, and judging whether the mass concentration ratio of the COD to the sulfate radical is equal to N, wherein N is more than or equal to 1.8 and less than or equal to 2.0; if the concentration is less than N, the lead-zinc beneficiation wastewater is conveyed to the second step for treatment; if the concentration is equal to N, directly conveying the lead-zinc beneficiation wastewater to the third step for treatment;
conveying the lead-zinc beneficiation wastewater into a hydrolysis acidification pool for treatment, wherein a carbon source is supplemented in the hydrolysis acidification pool to adjust the mass concentration ratio of COD (chemical oxygen demand) to sulfate radical in the lead-zinc beneficiation wastewater to be N;
step three, adding alkali liquor into the lead-zinc beneficiation wastewater directly conveyed in the step one or the lead-zinc beneficiation wastewater treated in the step two to adjust the pH value of the lead-zinc beneficiation wastewater to 6.0-6.2;
step four, enabling the wastewater obtained after the treatment in the step three to flow into an anaerobic reaction device, and mixing and contacting the wastewater with a sludge layer in the anaerobic reaction device to perform anaerobic treatment, so that macromolecular organic matters in the wastewater are decomposed into micromolecular organic matters and methane, and sulfate radicals are reduced into hydrogen sulfide; discharging gas substances generated by anaerobic treatment out of a water body, collecting the gas substances, making solid flow back to the sludge system, and making the water body enter the next step, namely step five, flowing the wastewater obtained after the treatment in the step four into an aerobic treatment system containing activated sludge for treatment so as to remove organic pollutants in the wastewater;
and step six, performing solid-liquid separation on the water sample treated in the step five, enabling the lower-layer concentrated sludge to flow back to the aerobic treatment system, and discharging the upper-layer clear liquid after the upper-layer clear liquid meets the discharge label through detection.
Preferably, in the second step, the carbon source is supplemented by:
adding a predetermined amount of straws into the hydrolysis acidification tank, and hydrolyzing organic matters in the straws to serve as a carbon source; or adding a predetermined amount of lactic acid into the hydrolysis acidification tank as a carbon source;
the alkali liquor added in the third step is lime water.
Preferably, the biological treatment method is characterized in that the hydrolysis acidification tank in the hydrolysis acidification tank is pre-filled with straw, lime and anaerobic sludge.
Preferably, the amount of anaerobic sludge: adding 150ml of anaerobic sludge into each liter of sewage to be treated;
adding amount of straws: the adding amount of the straws enables the mass concentration ratio of COD to sulfate radicals in the sewage to be N after the straws are decomposed, wherein N is more than or equal to 1.8 and less than or equal to 2.5;
the amount of lime: the added amount ensures that the pH value in the hydrolysis acidification tank is in the range of 7-7.5;
the anaerobic sludge is obtained by the following steps:
obtaining primary sludge from a municipal sewage treatment plant, inoculating the sludge to an anaerobic sludge bed of an anaerobic reaction device, operating a treatment system, and controlling the sewage entering the anaerobic reaction device to have the following conditions: pH6.0-6.2, carbon-sulfur ratio of 2:1, temperature of 28-33 ℃, SV30%, oxidation-reduction potential of-290-320, continuously running for 30 days to obtain anaerobic sludge, and putting into formal use.
Preferably, the biological treatment method is characterized in that the anaerobic reaction device is an up-flow anaerobic sludge bed reactor which comprises an anaerobic sludge bed, a sludge blanket, a three-phase separator and a gas collecting device.
Preferably, the biological treatment method is characterized in that in the anaerobic reaction device, compared with the volume of the anaerobic reaction device, the volume of inoculated sludge is 30-50%, the temperature in the anaerobic tank is controlled at 28-35 ℃, and the hydraulic retention time is 15-20 hours.
Preferably, any of the above biological treatment methods,
anaerobic sludge inoculated into the anaerobic reaction device is taken from a municipal sewage treatment plant;
the biological treatment method also comprises the step of culturing and domesticating the sludge in the anaerobic reaction device to obtain anaerobic sludge, and the specific steps are as follows:
obtaining primary sludge from a municipal sewage treatment plant, inoculating the primary sludge to an anaerobic sludge bed of an anaerobic reaction device, operating a treatment system, and controlling the sewage entering the anaerobic reaction device to have the following conditions: the pH value is 6.0-6.2, the carbon-sulfur ratio is 2:1, the temperature is 28-33 ℃, the SV is 30 percent, the oxidation-reduction potential is-290-320, the anaerobic sludge is obtained after continuous operation for 30 days, and the anaerobic sludge is put into formal use.
Preferably, the biological treatment method is characterized in that,
the aerobic sludge is obtained by aeration domestication of the anaerobic sludge under the conditions of ph 7.2-7.6, dissolved oxygen 3-4 mg/L, SV = 25-30% and MLSS = 2-5 g/L, wherein the aerobic sludge is rich in coccid, wireworm, rotifer, scuticociliatus and nematode and is put into formal use.
Preferably, the biological treatment method is characterized in that the aerobic treatment system comprises an aerobic tank; in the fifth step, an aeration device is arranged at the bottom of the aerobic tank, and a predetermined amount of air is aerated into the aerobic tank through the aeration device, so that the concentration of dissolved oxygen in the aerobic treatment system is adjusted to be 2 mg/L-4 mg/L.
Preferably, the biological treatment method is characterized in that in the aerobic treatment step of the step five, the hydraulic retention time is 5 to 10 hours.
Preferably, the biological treatment method is characterized by being used for treating lead-zinc beneficiation wastewater with sulfate radical mass concentration of 800-1800mg/L, COD concentration of 400-2000mg/L and conductivity of 2800-3900 mu s.
The sludge rich in microorganisms (sulfate reducing bacteria) obtained by controlling and culturing conditions such as pH, carbon-sulfur ratio, temperature, oxidation-reduction potential and the like has strong adaptability to the change fluctuation of water quality and water quantity; during operation, through comprehensive adjustment of the carbon-sulfur ratio, the pH value, the carbon source type, the anaerobic treatment condition and the aerobic treatment condition of the water body, the mass concentration of sulfate radicals is 800-1800mg/L, the COD concentration range is 400-2000mg/L, the conductivity range is 2800-3900 mu s, the removal efficiency of COD and high-concentration sulfate radicals of lead-zinc ore dressing wastewater reaches more than 90%, the removal rate of calcium ions reaches more than 60%, the conductivity is reduced by more than 40%, and the obtained treated water is recycled for ore dressing, is close to the original ore dressing index of production by adopting clean water, and meets the ore dressing index.
The activated sludge process has the advantages of environmental protection and economy, the activated sludge process is an ideal technical direction, but the lead-zinc beneficiation wastewater has huge yield, high salt content, high heavy metal content and large water quality fluctuation, the activated sludge process in the prior art is difficult to achieve the purpose of the invention, but the activated sludge has various microorganism types, each microorganism has nutrition preference and optimal condition different from other microorganisms, and competition exists among some microorganisms, the artificial culture/domestication of the activated sludge relates to various technical parameters, such as water pollutant composition, carbon source type, pH value, temperature and the like, and the change of each parameter can cause different dominant microorganism types, inhibited microorganisms and contents in the obtained sludge, so that the high-efficiency activated sludge which can simultaneously take multiple treatment purposes into consideration is difficult to obtain.
In the prior art, carbon-sulfur ratio is reported to influence competition of sulfate reducing bacteria and methanogen, and higher sulfate radical removal rate is obtained within a certain numerical range. For example, the modified activated sludge high-efficiency treatment high-concentration sulfate wastewater published in the university of south and China, school report of 6.6. Chai Liyuan, 2005, reports the effect of the ratio of COD/sulfate on the sulfate removal efficiency, and concludes that sulfate reducing bacteria dominate when the COD/sulfate is less than 1.7; when the content is more than 2.7, methanogens dominate; and it is concluded that when the ratio of COD/sulfate radical is 1.45-2.19 and the initial concentration of sulfate radical is 2000-4000mg/L, the sulfate radical removal rate is 44% after treatment for 4 days; quite interestingly, it was found that sulfate is not substantially treated at lower sulfate concentrations, e.g.below 1 g/L. Overall, this document discloses that the COD/sulfate concentration ratio affects the sulfate removal rate, but it does not yield sulfate removal rates exceeding 50% under the optimal conditions; but also depends on the sulfate radical concentration, and the sulfate radical in the sewage with the sulfate radical concentration lower than a certain value can not be treated; further, this document does not disclose the effect of removing COD. The concentration of the sulfate radical of the lead-zinc beneficiation wastewater to be treated by the method is just in the range which can not be treated by the method, the treatment time is short, the sulfate radical, COD (chemical oxygen demand), inorganic salt and treated water can be efficiently removed, and the treated water can reach the beneficiation index, so that the effect of the COD/sulfate radical ratio on the removal rate of the sulfate radical is not beneficial to solving the technical problem of the method.
In conclusion, the biological treatment method for removing sulfate radicals and COD in lead and zinc beneficiation wastewater at least has the following beneficial technical effects:
1) The wastewater is comprehensively treated, so that sulfate radicals and COD in the wastewater can be removed simultaneously, various detection indexes of the effluent quality can reach the limit value of a sewage discharge standard, and the detection value is greatly reduced;
2) The sludge (containing sulfate reducing bacteria) cultured by controlling the conditions of pH, carbon-sulfur ratio, temperature, oxidation-reduction potential and the like has strong adaptability to the change fluctuation of the water quantity and the water quality of the wastewater, the treatment effect is stable and reliable, and the industrial practicability is strong; test data show that the beneficiation sewage with the sulfate radical mass concentration of 800-1800mg/L and the COD concentration range of 400-2000mg/L can simultaneously realize the removal efficiency of sulfate radical and COD of more than 90%;
3) The treatment is carried out without adding any medicament; aiming at the wastewater with the ratio of the mass concentration of COD to the mass concentration of sulfate radical of 2:1, the hydrolysis step can be omitted, and any medicament is not added to supplement a carbon source, so that the cost can be greatly reduced;
4) The method has better treatment capacity for the beneficiation wastewater with higher conductivity (the range is 2800-3900 mu s), and can reduce the conductivity of the wastewater by more than 40%.
5) Low energy consumption, less residual sludge, impact load resistance and convenient operation and management.
Detailed Description
In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in more detail with reference to the following embodiments.
Example 1 configuration of a Sewage treatment System
1. Construction of Sewage treatment System hardware
The sewage reservoir, the hydrolysis acidification tank, the anaerobic reaction device, the aerobic reaction device and the secondary sedimentation tank are connected through pipelines.
2. Culture and acclimation of activated sludge
Obtaining primary sludge from a municipal sewage treatment plant, inoculating the primary sludge to an anaerobic sludge bed of an anaerobic reaction device, operating a treatment system, and controlling the sewage entering the anaerobic reaction device to have the following conditions: pH6.0-6.2, carbon-sulfur ratio of 2:1, temperature of 28-33 ℃, SV30%, oxidation-reduction potential of-290-320, continuously running for 30 days to obtain anaerobic sludge, and putting into formal use
The aerobic sludge is obtained by aeration domestication of the anaerobic sludge under the conditions of ph 7.2-7.6, dissolved oxygen 3-4 mg/L, SV = 25-30% and MLSS = 2-5 g/L, and the aerobic sludge is put into formal use after being rich in coccid, wireworm, rotifer, scuticocide and nematode.
3. Configuration of hydrolysis acidification pool
Adding straw, lime and anaerobic sludge in a hydrolysis acidification pool in advance, accelerating the decomposition of the straw through SRB, hydrolytic bacteria and lime in the sludge, and providing a carbon source for the SRB in a subsequent anaerobic system;
amount of anaerobic sludge: adding 150ml of anaerobic sludge into each liter of sewage to be treated;
adding amount of straws: the addition amount of the broken straws ensures that the mass concentration ratio of COD to sulfate radicals in the sewage is N after the straws are decomposed, wherein N is more than or equal to 1.8 and less than or equal to 2.0;
the amount of lime: the added amount ensures that the pH value in the hydrolysis acidification tank is in the range of 7-7.5.
Example 2.
The beneficiation wastewater discharged from a certain lead-zinc ore beneficiation plant is taken as a treatment object, and because the treated water sample is the production wastewater of the plant, when the production fluctuates, the chemical composition of the wastewater also changes to a certain extent, and the water quality analysis is shown in table 1:
table 1 example 2 water quality analysis table of treated water sample
Sample name SO 4 2- Ca 2+ pH value COD
Lead-zinc beneficiation wastewater 838～1625 535～1024 7.03～8.09 237～446
Specifically, the biological treatment method for removing sulfate radicals and COD in the lead-zinc beneficiation wastewater in the embodiment includes the following steps:
the method comprises the following steps: in order to ensure that the ratio of the mass concentration of COD to the mass concentration of sulfate in a treated water sample is about 2:1, wastewater enters a hydrolysis acidification pool filled with a proper amount of straws, and a carbon source is supplemented in a mode of hydrolyzing organic matters in the straws;
and adding alkali liquor to control the pH value of the water to be within the range of 6.0-6.2 so as to achieve the removal condition.
Step two: after hydrolysis and acidification are finished, wastewater flows into the bottom of an anaerobic sludge bed to be in mixed contact with sludge in a sludge layer, the sludge inoculation amount in an anaerobic tank is 30% -50%, the internal temperature of the anaerobic tank is controlled to be about 30 ℃, the hydraulic retention time is 20 hours, microorganisms in the anaerobic sludge decompose macromolecular organic matters in the wastewater into micromolecular organic matters and methane and reduce sulfate radicals into hydrogen sulfide, then a three-phase separator on the upper part of an anaerobic device is used for separating gas, solid and liquid in the system, the separated gas (mainly methane) is collected and treated, the solid returns to a sludge system through a return pipe, and water enters the next process.
Step three: and in the second step, hydrogen sulfide which does not separate from the water body enters the stripping equipment along with the water body, the water body is stripped by compressed air or inert gas, and then the hydrogen sulfide which separates from the water body enters the collector, so that the inhibition degree of the system is reduced.
Step four: the wastewater after the air stripping treatment enters an aerobic treatment system, and the wastewater is fully contacted with activated sludge in the system through an aeration device, so that organic pollutants in the wastewater are decomposed. The dissolved oxygen of the system is in the range of 2mg/L to 4mg/L, and the hydraulic retention time is 5h.
Step five: and the treated water sample overflows from the upper end of the aerobic tank and enters the bottom of the sedimentation tank, the mixed liquid is clarified through standing and sedimentation, the lower-layer concentrated sludge enters the aerobic treatment system through a return pipe and is recycled, and the upper-layer clear liquid overflows to form water.
Referring to table 2, the water quality analysis table of the water samples before and after treatment obtained by treating the lead-zinc beneficiation wastewater by the biological treatment method of the present application in this embodiment is shown; it should be noted that, because the treated water sample fluctuates within the production cycle, table 2 shows the water quality detection condition within a certain period of time, so as to illustrate the treatment effect of the present application;
table 2 example 2 water quality analysis table of water samples before and after treatment
Figure GDA0003932424100000061
Figure GDA0003932424100000071
As can be seen from the table 2, the lead-zinc beneficiation wastewater treated by the biological treatment method has good removal effect on sulfate radicals and COD, and has high removal rate, and all indexes reach the discharge standard.
In order to verify the influence of the treated water sample on the subsequent mineral separation stage, a closed-circuit comparison experiment is performed on the treated water sample and the original production according to the following table 3, and the test result shows that: the treated water sample can meet the mineral separation requirement.
Table 3 example 2 closed circuit comparative test results
Figure GDA0003932424100000072
Example 3
Lead-zinc beneficiation wastewater discharged from a certain factory is used as a treatment object, and is obtained by detection, wherein COD (chemical oxygen demand) in the wastewater is 1960mg/L, sulfate radical is 1100mg/L, and the condition that the ratio of the mass concentration of the COD to the mass concentration of the sulfate radical is N is met, so that the step of hydrolytic acidification reaction is omitted when a water sample is treated.
Specifically, the biological treatment method for removing sulfate radicals and COD in the lead-zinc beneficiation wastewater in the embodiment includes the following steps:
step one, monitoring and judging the mass concentration ratio of COD (chemical oxygen demand) and sulfate radical in the lead-zinc mineral separation wastewater, namely acquiring the water quality detection judging step, and the description is omitted here.
And step three, adding lime water into the water inlet barrel filled with the lead-zinc beneficiation wastewater in the step one to adjust the pH value of the lead-zinc beneficiation wastewater to 6.0-6.2, so as to achieve the removal condition.
And step four, carrying out anaerobic treatment on the wastewater obtained after the treatment in the step three so as to reduce sulfate radicals in the wastewater into hydrogen sulfide.
Specifically, the wastewater is subjected to anaerobic treatment through an up-flow anaerobic sludge bed reactor, wherein the up-flow anaerobic sludge bed reactor comprises an anaerobic sludge bed, a sludge blanket, a three-phase separator, a gas collecting device and other devices, and the specific structure is not described herein again; correspondingly, the anaerobic treatment step specifically comprises the following steps:
and 4.1, enabling the wastewater treated in the third step to flow into a reactor from the bottom of an anaerobic sludge bed and to be in mixed contact with sludge in a sludge blanket, wherein the sludge inoculation amount in the reactor is 30-50 percent (volume ratio of the sludge to the volume of the reactor), the internal temperature of an anaerobic tank is controlled to be about 30 ℃ (such as 27-33 ℃), the hydraulic retention time is 15 hours, and therefore, the microorganisms in the sludge are used for decomposing macromolecular organic matters in the wastewater into micromolecular organic matters and methane and reducing sulfate radicals into hydrogen sulfide.
And 4.2, separating gas, solid and liquid in the reactor through a three-phase separator at the upper part of the upflow anaerobic sludge bed reactor, wherein the separated gas (mainly methane) is collected and treated, the separated solid returns to a sludge layer through a return pipe, and the separated wastewater enters the fifth subsequent step.
Step five, treating the wastewater containing the hydrogen sulfide obtained after the treatment in the step four in hydrogen sulfide stripping equipment to remove the hydrogen sulfide in the wastewater; when the hydrogen sulfide stripping treatment is carried out on the wastewater, compressed air or inert gas is adopted, and then the hydrogen sulfide separated from the water body is collected by a collector, so that the inhibition degree of equipment is reduced.
Inputting the wastewater obtained after the stripping treatment in the fifth step into an aerobic treatment system for aerobic treatment so as to remove COD in the wastewater; wherein, the aerobic treatment system comprises an aerobic tank and activated sludge, and COD in the wastewater is decomposed by fully contacting the wastewater with the activated sludge.
Similarly, in the embodiment, a predetermined amount of air is aerated into the aerobic tank through an aeration device arranged at the bottom of the aerobic tank, so that the concentration of dissolved oxygen in the aerobic treatment system is adjusted to be 2 mg/L-4 mg/L, and the biological aerobic hydraulic retention time is 8 hours.
And step seven, overflowing the wastewater obtained after the aerobic treatment in the step six from the upper end of the aerobic tank into the bottom of a secondary sedimentation tank, standing and precipitating to clarify the mixed solution, allowing the lower-layer concentrated sludge to enter an aerobic treatment system through a return pipe for recycling, performing solid-liquid separation on the overflow effluent of the upper-layer clear liquid, and separating to obtain the water body meeting the sewage discharge standard (the sulfate radical content is lower than 100mg/L, and the COD content is lower than 50 mg/L).
Referring to table 4, the water quality analysis table of the water samples before and after treatment obtained by treating the lead-zinc beneficiation wastewater by the biological treatment method of the present application in this embodiment is shown;
table 4 water quality analysis table of water samples before and after treatment in example 3
Figure GDA0003932424100000081
Figure GDA0003932424100000091
Also, as can be seen from table 4, the lead-zinc beneficiation wastewater treated by the biological treatment method has good removal effect on sulfate radicals and COD, and has high removal rate, and each index reaches the discharge standard.
Similarly, the treated water samples were subjected to a closed-loop comparative experiment with the original production, as shown in the following Table 5, from which it can be seen that: the treated water sample can meet the mineral separation requirement.
Table 5 example 3 closed circuit comparative test results
Figure GDA0003932424100000092
Example 4.
The lead-zinc beneficiation wastewater discharged from a certain factory is used as a treatment object, and the detection result shows that the COD in the wastewater is 410mg/L, the sulfate radical is 1330mg/L, and the condition that the ratio of the mass concentration of the COD to the mass concentration of the sulfate radical is N is not met, so the steps for treating the water sample are consistent with the steps in the embodiment 1.
Specifically, the biological treatment method for removing sulfate radicals and COD in the lead-zinc beneficiation wastewater in the embodiment includes the following steps:
step one, detecting the mass concentration of COD and sulfate radical in the lead-zinc beneficiation wastewater (namely the water quality detection step), and calculating by comparison to know that the ratio of the mass concentration of the COD to the mass concentration of the sulfate radical is less than N, and at the moment, conveying the lead-zinc beneficiation wastewater to the step two for treatment.
Step two, in order to ensure that the ratio of the mass concentration of COD to the mass concentration of sulfate radical in the treated water sample falls into the value range of N, the lead-zinc beneficiation wastewater needs to be conveyed into the hydrolytic acidification tank for treatment;
lactic acid can also be used as a carbon source; and the appropriate amount of the carbon source means that the ratio of the mass concentration of COD to the mass concentration of sulfate radical can fall into the value range of N after the hydrolysis acidification is finished.
And step three, adding lime water into the lead-zinc beneficiation wastewater treated in the step two to adjust the pH value of the lead-zinc beneficiation wastewater to 6.0-6.2 so as to achieve a removal condition.
And step four, carrying out anaerobic treatment on the wastewater obtained after the treatment in the step three by using an up-flow anaerobic sludge bed reactor to reduce sulfate radicals in the wastewater into hydrogen sulfide.
Similarly, the sub-steps specifically include:
and 4.1, enabling the wastewater treated in the third step to flow into a reactor from the bottom of an anaerobic sludge bed and to be in mixed contact with sludge in a sludge blanket, further controlling the inoculation amount of the sludge in the reactor to be 30-50%, controlling the internal temperature of an anaerobic tank to be 28-35 ℃, and controlling the hydraulic retention time to be 18 hours, so that macromolecular organic matters in the wastewater are decomposed into micromolecular organic matters and methane through microorganisms in the sludge, and sulfate radicals are reduced into hydrogen sulfide.
And 4.2, separating gas, solid and liquid in the reactor through a three-phase separator at the upper part of the upflow anaerobic sludge blanket reactor, wherein the separated gas (mainly methane) is collected and treated, the separated solid returns to a sludge blanket through a return pipe, and the separated wastewater enters the fifth subsequent step.
Step five, treating the wastewater containing the hydrogen sulfide obtained after the treatment in the step four in hydrogen sulfide stripping equipment to remove the hydrogen sulfide in the wastewater; when the waste water is subjected to hydrogen sulfide stripping treatment, compressed air or inert gas is adopted, and then hydrogen sulfide separated from a water body enters a collector, so that the inhibition degree of equipment is reduced.
Inputting the wastewater obtained after the stripping treatment in the fifth step into an aerobic treatment system for aerobic treatment so as to remove COD in the wastewater; wherein, the aerobic treatment system comprises an aerobic tank and activated sludge, and COD in the wastewater is decomposed by fully contacting the wastewater with the activated sludge.
Also, in this embodiment, a predetermined amount of air is aerated into the aerobic tank through an aeration device provided at the bottom of the aerobic tank, so that the concentration of dissolved oxygen in the aerobic treatment system is adjusted to a predetermined concentration value of 2mg/L to 4mg/L, and the biological aerobic hydraulic retention time is 10 hours.
And step seven, overflowing the wastewater obtained after the aerobic treatment in the step six from the upper end of the aerobic tank into the bottom of a secondary sedimentation tank, standing and precipitating to clarify the mixed solution, allowing the lower-layer concentrated sludge to enter an aerobic treatment system through a return pipe for recycling, performing solid-liquid separation on the overflow effluent of the upper-layer clear liquid, and separating to obtain the water body meeting the sewage discharge standard (the sulfate radical content is lower than 100mg/L, and the COD content is lower than 50 mg/L).
Referring to table 6, the water quality analysis table of the water samples before and after treatment obtained by treating the lead-zinc beneficiation wastewater by the biological treatment method of the present application in this example is shown; similar to example 1, the treatment effect of the present application is still illustrated by the water quality detection condition within a certain period of time because the treated water sample fluctuates within the production cycle;
table 6 water quality analysis table of water samples before and after treatment in example 4
Figure GDA0003932424100000101
Figure GDA0003932424100000111
It can be seen through table 6 that, lead zinc ore dressing waste water after handling through this application biological treatment method all has fine removal effect to sulfate radical and COD, and the clearance is high moreover, and sewage conductivity reduces to 1758 from 3815, and each index all reaches emission standard.
Similarly, in order to verify the influence of the treated water sample on the subsequent beneficiation stage, a closed-circuit comparison experiment is performed on the treated water sample and the original production according to the following table 7, and the test result shows that: the treated water sample can meet the mineral separation requirement and reaches almost the same level as the original production by adopting clear water.
Table 7 example 4 closed circuit comparative test results
Figure GDA0003932424100000112
According to the application examples, the method provided by the invention can ideally remove sulfate radicals, COD (chemical oxygen demand) and inorganic salts from the lead-zinc beneficiation wastewater within a large water quality difference range, and the treated water can reach the beneficiation index after being recycled and beneficiated; the method can be realized by depending on the configuration of the conventional sewage treatment system, no reagent is required to be added in the treatment process, and the cost is extremely low; and straw is selected as a carbon source, agricultural wastes such as straw and the like are degraded into short-chain organic matters which can be digested by an anaerobic biological pool in the hydrolysis acidification process, and the short-chain organic matters are used as the carbon source to supplement sulfate radical reducing bacteria, so that the cost is low, the material source is wide, the biodegradation performance is good, and the short-chain organic matters are used as an external carbon source for treating wastewater by a biological method, so that the treatment effect is improved, and an effective path is provided for resource utilization of the biomass wastes.
The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (5)

1. A biological treatment method for removing sulfate radicals and COD in lead-zinc beneficiation wastewater is characterized in that the method is used for treating the lead-zinc beneficiation wastewater with the mass concentration of sulfate radicals being 800-1800mg/L, the COD concentration range being 400-2000mg/L and the conductivity range being 2800-3900 mu s, and the method specifically comprises the following steps:
step one, detecting the mass concentration of COD and sulfate radical in lead-zinc mineral processing wastewater, and judging whether the mass concentration ratio of the COD to the sulfate radical is equal to N, wherein N is more than or equal to 1.8 and less than or equal to 2.5; if the concentration is less than N, the lead-zinc beneficiation wastewater is conveyed to the second step for treatment; if the concentration is equal to N, directly conveying the lead-zinc beneficiation wastewater to the third step for treatment;
conveying the lead-zinc beneficiation wastewater into a hydrolysis acidification pool for treatment, wherein a carbon source is supplemented in the hydrolysis acidification pool to adjust the mass concentration ratio of COD (chemical oxygen demand) to sulfate radical in the lead-zinc beneficiation wastewater to be N; wherein, the carbon source supplementing mode is as follows:
adding a preset amount of straws into the hydrolysis acidification pool, and hydrolyzing organic matters in the straws to serve as a carbon source; or adding a predetermined amount of lactic acid into the hydrolysis acidification tank as a carbon source;
step three, adding alkali liquor into the lead-zinc beneficiation wastewater directly conveyed in the step one or the lead-zinc beneficiation wastewater treated in the step two to adjust the pH value of the lead-zinc beneficiation wastewater to 6.0-6.2; wherein the added alkali liquor is lime water;
step four, enabling the wastewater obtained after the treatment in the step three to flow into an anaerobic reaction device, and mixing and contacting the wastewater with a sludge layer in the anaerobic reaction device to perform anaerobic treatment, so that macromolecular organic matters in the wastewater are decomposed into micromolecular organic matters and methane, and sulfate radicals are reduced into hydrogen sulfide; discharging gas substances generated by anaerobic treatment out of a water body and collecting the gas substances, so that the solid flows back to a sludge system, and the water body enters the next procedure;
step five, enabling the wastewater obtained after the treatment in the step four to flow into an aerobic treatment system containing activated sludge for treatment so as to remove organic pollutants in the wastewater;
step six, performing solid-liquid separation on the water sample treated in the step five, allowing the lower-layer concentrated sludge to flow back to an aerobic treatment system, and discharging the upper-layer clear liquid after the detection meets the discharge label;
in the second step, straw, lime and anaerobic sludge are pre-added into the hydrolysis acidification tank;
amount of anaerobic sludge: adding 150ml of anaerobic sludge into each liter of sewage to be treated;
adding amount of straws: the addition amount of the broken straws ensures that the mass concentration ratio of COD to sulfate radicals in the sewage is N after the straws are decomposed, wherein N is more than or equal to 1.8 and less than or equal to 2.5;
the amount of lime: the added amount ensures that the pH value in the hydrolysis acidification tank is in the range of 7-7.5;
anaerobic sludge pre-added into the hydrolytic acidification tank and anaerobic sludge inoculated into the anaerobic reaction device are all taken from urban sewage treatment plants, and specifically, the anaerobic sludge is obtained through the following steps:
obtaining primary sludge from a municipal sewage treatment plant, inoculating the sludge to an anaerobic sludge bed of an anaerobic reaction device, operating a treatment system, and controlling the sewage entering the anaerobic reaction device to have the following conditions: pH6.0-6.2, carbon-sulfur ratio of 2:1, temperature of 28-33 ℃, SV30%, oxidation-reduction potential of-290-320, continuously running for 30 days to obtain anaerobic sludge, and putting into formal use;
and in addition, the aerobic sludge in the step five is obtained by aeration acclimation of the anaerobic sludge under the conditions of ph 7.2-7.6, dissolved oxygen of 3-4 mg/L, SV = 25-30% and MLSS = 2-5 g/L, wherein the aerobic sludge is rich in infusorium, raschia tiruca, rotifer, scuticocilia and nematodes and then is put into formal use.
2. The biological treatment method according to claim 1, wherein the anaerobic reaction device is an upflow anaerobic sludge blanket reactor including an anaerobic sludge blanket, a three-phase separator, and a gas collecting device.
3. The biological treatment method according to claim 2, wherein in the anaerobic reaction apparatus, the inoculation amount is 30 to 50% in comparison with the volume of the anaerobic reaction apparatus in the volume of the inoculated sludge, the temperature inside the anaerobic tank is controlled to be 28 to 35 ℃, and the hydraulic retention time is 15 to 20 hours.
4. The biological treatment process of claim 1, wherein the aerobic treatment system comprises an aerobic tank; and in the fifth step, an aeration device is arranged at the bottom of the aerobic tank, and a predetermined amount of air is aerated into the aerobic tank through the aeration device, so that the concentration of dissolved oxygen in the aerobic treatment system is adjusted to be 2-4 mg/L.
5. The biological treatment method as set forth in claim 4, wherein in the aerobic treatment step of the fifth step, the hydraulic retention time is 5 to 10 hours.
CN202110482551.6A 2021-04-30 2021-04-30 Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater Active CN113402104B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110482551.6A CN113402104B (en) 2021-04-30 2021-04-30 Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110482551.6A CN113402104B (en) 2021-04-30 2021-04-30 Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater

Publications (2)

Publication Number Publication Date
CN113402104A CN113402104A (en) 2021-09-17
CN113402104B true CN113402104B (en) 2022-12-09

Family

ID=77677823

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110482551.6A Active CN113402104B (en) 2021-04-30 2021-04-30 Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater

Country Status (1)

Country Link
CN (1) CN113402104B (en)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5587079A (en) * 1995-04-21 1996-12-24 Rowley; Michael V. Process for treating solutions containing sulfate and metal ions.
CN103771670B (en) * 2012-10-20 2015-07-15 中国石油化工股份有限公司 Method and apparatus for removing sulfate in high-salt petrochemical wastewater
CN105084649B (en) * 2015-07-21 2017-07-07 广州大学 It is a kind of while the method for removing sulfate ion and thallium ion in sulfuric acid plant waste discharge

Also Published As

Publication number Publication date
CN113402104A (en) 2021-09-17

Similar Documents

Publication Publication Date Title
CN107010788B (en) Large-scale pig farm cultivation wastewater treatment system and method
CN104961306B (en) A kind of processing method of vaccary breeding wastewater
CN103524001B (en) Treatment method for high fat food processing wastewater
CN102649616A (en) Comprehensive treatment method for garbage leachate
CN1631818A (en) Organic waste water treatment process
CN106277555B (en) High-efficiency low-cost treatment method and system for coking wastewater
CN101224936A (en) Process for treating coking wastewater
CN1772661A (en) Combined treatment process for manioc producing effluent
CN103011526A (en) Method for treating erythromycin thiocyanate wastewater
US20170066668A1 (en) Highly effective sewage treatment based on regulation and control of directed electron flow and apparatus thereof
CN103395937A (en) Processing device and processing method applicable to high-ammonia-nitrogen agricultural wastewater
CN1907889A (en) Apparatus and method of treating city domestic refuse percolation liquid by two-stage UASB+A/O technique
CN105800796A (en) Floatation wastewater biological treatment process
CN109179918A (en) A kind of biochemical processing method for refuse landfill landfill leachate
CN114590959A (en) ECOF four-micro-physical sewage treatment system, treatment process and application
CN202297315U (en) Dedicated device for wastewater treatment of phenolic resin
CN107055963B (en) Efficient and low-consumption advanced treatment device and treatment method for landfill leachate
CN107662976B (en) Method for efficiently and anaerobically degrading fulvic acid in leachate of waste incineration
CN100506722C (en) Treatment of high-concentration oily waste water
CN112047468A (en) Biochemical treatment method of landfill leachate
CN113402104B (en) Biological treatment method for removing sulfate radical and COD in lead-zinc ore dressing wastewater
CN218811022U (en) Integrated treatment device for deep denitrification of garbage penetration filtrate
CN102923910B (en) Efficient and deep treatment process for high-concentration waste water in natural gas industry
CN101823808A (en) Garbage leachate treatment process
CN111484136B (en) Energy-saving sewage treatment system and process with high effluent standard

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant