JP2023016647A - Method for accelerating startup of anaerobic reactors based on conductive materials - Google Patents

Abstract

To provide a method to facilitate rapid startup of anaerobic reactors suitable for a variety of organic loads.SOLUTION: It is a method of accelerating a startup of anaerobic reactors based on conductive nanomaterial, whereby a conductive nanomaterial composite anaerobic activated sludge is prepared and the prepared conductive nanomaterial composite anaerobic activated sludge is inoculated into the anaerobic reactor at a volume concentration of 5 to 18 gVSS/L to start the anaerobic reactor.SELECTED DRAWING: Figure 1

Description

FIELD OF THE INVENTION The present invention relates to the technical field of anaerobic biological treatment of wastewater, and in particular to a method for promoting start-up of anaerobic reactors based on conductive nanomaterials.

Anaerobic biological treatment technology is the process of converting organic matter into methane and carbon dioxide under anaerobic conditions by anaerobic and facultative anaerobic microbial communities, also called anaerobic digestion, generally Organic matter in wastewater is complex and is decomposed in four steps by anaerobic digestion as follows.
(1) Hydrolysis step: Due to the large molecular volume of macromolecular organic substances, they cannot directly pass through the cell walls of anaerobic bacteria, and are decomposed into small molecules by extracellular enzymes outside the microorganisms, and then in the wastewater. Typical organic substances such as cellulose are degraded by cellulases into cellobiose and glucose, starches are degraded into maltose and glucose, proteins are degraded into short peptides and amino acids, and after degradation these small molecules are transformed into It can enter the body of the cell through the cell wall for the step.
(2) oxidation step: the above small molecule organics enter the cell body, change into simpler compounds, and are distributed outside the cell, the main products of this step are volatile fatty acids (VFA), alcohols, Several products such as lactic acid, carbon dioxide, hydrogen, ammonia and hydrogen sulfide are also produced.
(3) Acetogenic step: At this stage the products of the previous step are further converted to acetic acid, carbonic acid, hydrogen and new cellular material.
(4) The Methanogenic Step: At this stage, acetic acid, hydrogen, carbonic acid, formic acid, and methanol are all converted to methane, carbon dioxide, and new cellular material, and this stage is the most important step in the overall anaerobic process. and is also the rate-limiting step in the overall anaerobic reaction process.
However, the initiation of anaerobic digestion is a slow and highly fragile process, recognized as a major impediment to engineering applications. The traditional start-up phase is
The acclimation of microorganisms by altering the hydraulic retention time or organic loading rate to improve the throughput of the reactor, which involves continuous or intermittent changes in hydraulic retention time or organic loading rate. means that is unavoidable. In addition, pH, temperature, alkalinity,
and interference caused by fluctuations in inflow characteristics make it more difficult to initiate anaerobic digestion, especially due to acid accumulation due to high organic loading. Recent studies have shown that direct electron transfer between species in cotrophic communities can be achieved through conductive appendages and/or redox proteins, improving the stability of anaerobic systems. Therefore, conductive materials such as activated carbon, graphite, biochar, and nano- to micron-sized ferrous materials (magnetite, zero-valent iron, hematite, etc.) can be provided to facilitate interaction between hydrogen-producing acetogenic and methanogenic archaea. Nanomaterials are widely used due to their unique physical and chemical properties, at the same time they can stimulate the electron transport of , further improve the efficiency of methanogenesis and facilitate the rapid initiation of anaerobic digestion. , the use of nanoscale conductive materials may further improve the stability of anaerobic systems, as they not only possess stable surface properties, but also have good biocompatibility.
Chinese patent CN108017148A discloses a rapid culture step involving the introduction of bacteria and anaerobic particles, wherein the rapid culture step of anaerobic particles consists of 1) selecting anaerobic sludge suitable for cultivation; ) Gradually increase the inflow COD load: depending on the amount of sludge in the reactor cultured in step 1), the sludge COD load, and the outflow COD and VFA
Gradually increasing the OD load and 3) depending on the influent concentration reached in step 2), the reflux ratio, the ratio of the inflow to the outflow, is reduced to 1:1 to reduce the effect of the inflow load on the system.
At the same time, adjusting the alkalinity of the combined liquor to reduce the consumption of alkalinity, the total start-up time is 20-25 days, but the anaerobic sludge is It is used to accelerate the start-up of the anaerobic reactor, but the start-up time is still long, the introduction of chemicals, etc. has the risk of secondary pollution, and the effect is relatively short.
Therefore, in order to optimize and solve the above technical problems, a method is needed to facilitate rapid start-up of anaerobic reactors suitable for various organic loads.

In view of the problems existing in the prior art, the inventors unexpectedly discovered that composites of nano-conductive materials and anaerobic activated sludge can facilitate rapid start-up of anaerobic reactors.
The object of the present invention is a method for preparing an electrically conductive nanomaterial composite anaerobic activated sludge and an anaerobic process based on electrically conductive nanomaterials, comprising inoculating an anaerobic reactor with the electrically conductive nanomaterial composite anaerobic activated sludge. Another object of the present invention is to provide a method for accelerating the start-up of a sex reactor.

The above solution specifically includes the following steps.
Conductive nanomaterial composite anaerobic activated sludge is prepared, the prepared conductive nanomaterial composite anaerobic activated sludge is inoculated into an anaerobic reactor at a volume concentration of 5 to 18 gVSS / L, and the anaerobic reactor to start.
Among them, the preparation method of said conductive nanomaterial composite anaerobic activated sludge is as follows.
adding the conductive nanomaterial to deionized water and dispersing it with ultrasonic waves to prepare a conductive nanomaterial dispersion solution;
The prepared conductive nanomaterial dispersion solution is added to the anaerobic activated sludge and stirred for 22 hours to obtain conductive nanomaterial composite anaerobic activated sludge.
Furthermore, the mass ratio of the conductive nanomaterial in the conductive nanomaterial composite anaerobic activated sludge to the dry weight of the anaerobic activated sludge is (0.03 to 0.15):1.
Further, when the anaerobic reactor is started, the pH is 6.7-7.5 and the temperature is 27-36°C.
and COD:N:P is (400-200):(7
~3): 1.
Further, the anaerobic activated sludge is any one of flocculated sludge and particulate sludge. Among them, it is either the residual sludge of the flocculated sludge municipal sewage treatment plant or the sludge of the sludge thickening tank, but is not limited to the above anaerobic activated sludge. The anaerobic reactor is any one of a normal digester, an anaerobic catalytic digester, an upflow anaerobic sludge bed, or an anaerobic particulate sludge expanded bed.
Further, the stirring method is as follows. Incubate for 22 hours with mechanical agitation, agitation speed 1
Grow anaerobic at 20 rpm.
According to one aspect of the present invention, the conductive nanomaterial of the above solution is nano triiron tetroxide, and the particle size of said nano triiron tetroxide is 20-30 nm.
According to another aspect of the invention, the conductive nanomaterial of the above solution is modified nano triiron tetroxide,
The modified nano-triiron tetroxide and the nano-triiron tetroxide are equivalent, and the preparation method of said modified nano-triiron tetroxide is as follows.
1) The molar ratio of aniline monomer to Fe(NO ₃ ) _{3.9H 2} O is 1:0.45 to 1.94
Fe(NO ₃ ) _{3.9H 2} O is dissolved in absolute ethanol and the aniline monomer is dissolved in absolute ethanol such that
2) Next, after adding nitrogen gas to the magnetic ring reaction tube so that the filling amount in the magnetic ring reaction tube is equal to or less than the height of the magnetic ring, nitrogen gas is added to the magnetic ring reaction tube so that the pressure becomes 2.5 MPa. and heat the magnetic ring reaction tube to 180-200° C. to react for 6-8 hours.
3) After 30 minutes from the start of the reaction, the electromagnetic ring of the magnetic ring reaction tube is switched between the reaction zone and the low temperature zone of the reaction tube main body at a frequency of 45 to 90 s/time to adsorb and fix the modified nano triiron tetroxide produced. Then, when the electromagnetic ring is energized, the residence time in the reaction zone and the low temperature zone is 3 to 5
s, and the temperature of the cold zone is controlled at 80-110°C.
4) The prepared precipitate is collected by centrifugation, washed and dried to obtain modified nano triiron tetroxide.
Using the above method, it is possible to partially reduce ferric iron to ferric iron using aniline monomers without adding additional substances, and the effect of triiron tetroxide At the same time, ferric and trivalent iron can catalyze the polymerization of aniline monomers to realize the preparation of triiron tetroxide/polyaniline composite nanomaterials, which continues after the initiation of the reaction. The modified triiron tetroxide generated in the magnetic field is magnetically attracted and moved to a low temperature region for short-term temperature difference switching. found to be beneficial in stabilizing the magnetic properties, at the same time, in subsequent use, the start-up of anaerobic reactors, because the modified triiron tetroxide has more stable magnetic and electrical conductivity, etc. Conductive nanomaterials are used as electron transfer mediators to enhance the catabolism of VFAs during acceleration, effectively avoiding large accumulations of VFAs in the reactor, buffering the pH and lowering the redox potential. It plays a role in promoting the growth of anaerobes, creates an environment that promotes the growth of anaerobes, strengthens and concentrates anaerobes that have the ability to directly transfer electrons between species, and increases the methane production rate of anaerobes.

The invention has the following beneficial effects.
(1) The method for promoting start-up of a conductive nanomaterial anaerobic reactor of the present invention uses triiron tetroxide or modified triiron tetroxide as a conductive nanomaterial, and during the start-up of the anaerobic reactor, the conductive Using organic nanomaterials to effectively avoid the accumulation of large amounts of volatile fatty acid VFAs in the anaerobic reactor, play a role in buffering pH and lowering the redox potential, and promoting the growth of anaerobes Create an environment, strengthen and concentrate anaerobes that have the ability to directly transfer electrons between species, and increase the methane production rate of anaerobes.
(2) The method of promoting start-up of the conductive nanomaterial anaerobic reactor of the present invention uses triiron tetroxide or modified triiron tetroxide as the conductive nanomaterials, which are acidogenic and methanogenic bacteria. can be used as an electron transfer to enhance the efficiency of electron transfer between the Forming anaerobic granular sludge with large biomass and good sedimentation performance, which improves the organic load resistance of the anaerobic reactor, enhances the stable and rapid start-up of the anaerobic reactor under high organic load, Its scope of application is wide, and in the conventional technology, the method of adding activated carbon only uses the high physical adsorption capacity formed by the large specific surface area and the high porosity of activated carbon to accelerate the formation of bacterial micelles, and the microorganisms can be immobilized to prevent sludge loss, the device can be started quickly, and is suitable for low-load anaerobic reactors, and its scope of application is relatively limited.
(3) The conductive nanomaterials, such as nano triiron tetroxide and modified nano triiron tetroxide, provided by the method for promoting the start-up of the conductive nanomaterial anaerobic reactor of the present invention have a small synthesis particle size and excellent surface performance. is stable and biocompatible, and at the same time, in anaerobic digestion systems, there is a direct interspecific electron transfer process between cotrophic bacterial communities, and to enhance the process of direct interspecific electron transfer, Introducing conductive nanomaterials into anaerobic digestion systems facilitates rapid initiation of anaerobic digestion, especially when faced with high organic loads.
(4) The method for promoting the start-up of a conductive nanomaterial anaerobic reactor of the present invention comprises preparing a composite anaerobic activated sludge using activated sludge and a conductive nanomaterial, inoculating it into an anaerobic reactor, It can improve the organic load resistance of the anaerobic reactor more effectively than the method of directly adding conductive nanomaterials to the anaerobic reactor, which leads to a stable and rapid start-up of the anaerobic reactor under high organic loading. is further enhanced, shortening the start-up period of the anaerobic reactor.
(5) The method for promoting the start-up of the conductive nanomaterial anaerobic reactor of the present invention is to combine anaerobic activated sludge and conductive nanomaterials (nano triiron tetroxide, modified nano triiron tetroxide) into anaerobic Compared to the case where the anaerobic reactor is inoculated and no nano triiron tetroxide is added, the start-up period of the anaerobic reactor is 11.8 to 22
. 1% shorter, 9 start-up periods compared to adding _SiO2 nanoparticles (non-conductive)
. 7-19.5% shortened, the start-up cycle of the anaerobic reactor was shortened by 14.7-25.4% compared to the case without the addition of modified nano-triiron tetroxide, and _SiO2 nanoparticles (non-conductive ), the start-up period is shortened by 12.2-23.5%, the maximum load that the anaerobic reactor can reach is greatly improved, and the COD removal rate is greatly improved.
(6) The method of promoting the start-up of the conductive nanomaterial anaerobic reactor of the present invention can be used in the anaerobic digestion system of inoculated granular sludge and flocculated sludge, and has a wide range of applications, and the anaerobic reactor can be stabilized. It can be added directly to an existing anaerobic reactor without changing the structure of the anaerobic reactor, is easy to operate, and has low running costs, making it easy to spread and use.

Effluent COD, methane production rate, and pH changes during reactor start-up period under different OLR, (A) is effluent COD, (B) is COD removal rate, (C) is methane production rate. , (D) indicates pH (error bars represent standard deviation of triplicate samples). Distribution map of VFAs in three reactors according to increasing OLR, (A) for R0, (B) for R1 and (C) for R2. Dynamic changes of INT-ETS and CV curves of different step reactors are shown, (A) INT-ETS, (B) CV curves, error bars represent standard deviation of triplicate samples. Shows the change in EPS composition of sludge at different times, (A1)-(D1) show LB-EPS composition change at 65 days, 75 days, 114 days, 152 days, (A2)-(D2) at 65 days , TB-EPS composition changes at 75, 114 and 152 days. Relative abundance changes of phylogenetic sets at the genus level of bacterial communities in reactors R0, R1 and R2 at days 0, 50 and 150, (A) bacterial communities, (B) indicates an archaeal community, and sequences that account for less than 2% of the total are classified as 'other'. 1 is an overall external view of a magnetic ring reaction tube of the present invention; FIG. FIG. 3 is a partial cross-sectional structural schematic view of the magnetic ring reaction tube of the present invention; FIG. 4 is a structural schematic diagram of the drive components of the magnetic ring reaction tube of the present invention;

[Description of symbols]
1 Reaction tube body 11 Seal cover 12 Temperature control rod 13 Heating plate 2 Electromagnetic ring 3 Guide ring 4 Drive component 41 Drive motor 42 Drive gear ring 43 First screw 44 Second screw 45 First gear 46 Second gear 5 Housing 6 Pedestal

In the following, the invention will be described in more detail with reference to specific embodiments in order to better reflect the advantages of the invention.

Example 1
Example 1 is an anaerobic reactor inoculated with anaerobic activated sludge containing conductive nano triiron tetroxide, specifically as follows.
A method for promoting start-up of an anaerobic reactor based on conductive nanomaterials uses conductive nanomaterials to facilitate start-up of an anaerobic reactor and includes the following steps.
Conductive nanomaterial composite anaerobic activated sludge was prepared, and the prepared conductive nanomaterial composite anaerobic activated sludge was inoculated into the EGSB anaerobic reactor at a volume concentration of 12gVSS/L, and the EGSB anaerobic reactor was and when the EDSB anaerobic reactor is started, the pH is brought to 6.7-7.5
, the temperature is controlled at 35° C. and the COD:N:P is 200:5:1 during the start-up process of the EGSB anaerobic reactor.
In it, the method for preparing the conductive nanomaterial composite anaerobic activated sludge comprises:
The conductive nanomaterials are added to deionized water and dispersed by ultrasonic waves. The ultrasonic waves are dispersed for 30 minutes, the power is 200 W, and a conductive nanomaterial dispersion solution is prepared. It is triiron oxide, and the particle size of the nano triiron tetroxide is 20 to 30 nm.
The prepared conductive nanomaterial dispersion solution is added to the anaerobic activated sludge, and the large particles taken out from the sludge thickening tank of the anaerobic activated sludge urban sewage treatment plant are sieved, and the conductive nanomaterial composite anaerobic activated The mass ratio of the conductive nanomaterial in the sludge and the dry weight of the anaerobic activated sludge is 0.1:
1, cultured for 22 hours with mechanical stirring, anaerobic culture at a stirring speed of 120 rpm to obtain conductive nanomaterial composite anaerobic activated sludge.

Example 2
Example 2 is an anaerobic reactor inoculated with anaerobic activated sludge containing conductive nano triiron tetroxide, specifically as follows.
A method for promoting anaerobic reactor start-up based on conductive nanomaterials uses conductive nanomaterials to facilitate anaerobic reactor start-up and includes the following steps.
Conductive nanomaterial composite anaerobic activated sludge is prepared, the prepared conductive nanomaterial composite anaerobic activated sludge is inoculated into the EGSB anaerobic reactor at a volume concentration of 5 gVSS / L, and the EGSB anaerobic reactor is When the EDSB anaerobic reactor is started, the pH is controlled to 6.7-7.5, the temperature is 27° C., and the COD:N:P is controlled during the start-up process of the EGSB anaerobic reactor. 40
0:8:1.
In it, the method for preparing the conductive nanomaterial composite anaerobic activated sludge comprises:
The conductive nanomaterial is added to deionized water and dispersed with ultrasonic waves, and dispersed with ultrasonic waves for 30 minutes. It is iron, and the particle size of the nano triiron tetroxide is 20 to 30 nm.
The prepared conductive nanomaterial dispersion solution is added to the anaerobic activated sludge, and the anaerobic activated sludge is taken out from the sludge thickening tank of the municipal sewage treatment plant and sieved for large particles, and the conductive nanomaterial composite anaerobic activated The mass ratio of the conductive nanomaterial in the activated sludge and the dry weight of the anaerobic activated sludge is 0.0
5:1, cultured for 22 hours with mechanical agitation, anaerobic culture at agitation speed of 120 rpm,
A conductive nanomaterial composite anaerobic activated sludge is obtained.

Example 3
Example 3 is an anaerobic reactor inoculated with anaerobic activated sludge containing conductive nano triiron tetroxide, specifically as follows.
A method for promoting anaerobic reactor start-up based on conductive nanomaterials uses conductive nanomaterials to facilitate anaerobic reactor start-up and includes the following steps.
Conductive nanomaterial composite anaerobic activated sludge was prepared, and the prepared conductive nanomaterial composite anaerobic activated sludge was inoculated into the EGSB anaerobic reactor at a volume concentration of 18gVSS/L, and the EGSB anaerobic reactor and when the EDSB anaerobic reactor is started, the pH is brought to 6.7-7.5
, the temperature is controlled at 36° C. and the COD:N:P is 300:2:1 during the start-up process of the EGSB anaerobic reactor.
In it, the method for preparing the conductive nanomaterial composite anaerobic activated sludge comprises:
The conductive nanomaterial is added to deionized water and dispersed with ultrasonic waves, and dispersed with ultrasonic waves for 30 minutes. It is iron, and the particle size of the nano triiron tetroxide is 20 to 30 nm.
The prepared conductive nanomaterial dispersion solution is added to the anaerobic activated sludge, and the anaerobic activated sludge is taken out from the sludge thickening tank of the municipal sewage treatment plant and sieved for large particles, and the conductive nanomaterial composite anaerobic The mass ratio of the conductive nanomaterial in the activated sludge to the dry weight of the anaerobic activated sludge is 0.
2:1, cultured for 22 hours with mechanical agitation, anaerobic culture at agitation speed of 120 rpm,
A conductive nanomaterial composite anaerobic activated sludge is obtained.

Example 4
This example is basically the same as Example 1, except that the conductive nanomaterial is modified nano triiron tetroxide, and the method for preparing the modified nano triiron tetroxide comprises:
₁ ) Fe( _NO3 ) _3.9H2O was dissolved in absolute ethanol such that the molar ratio of aniline monomer and Fe( _NO3 ) _3.9H2O was ₁ :1.45, and the aniline monomer was Dissolve in absolute ethanol.
2) Next, add to the magnetic ring reaction tube, fill the magnetic ring reaction tube so that the amount of filling is equal to or less than the height of the magnetic ring, and then flow nitrogen gas into the magnetic ring reaction tube so that the pressure becomes 2.5 MPa, The magnetic ring reaction tube is heated to 195° C. and reacted for 7 hours.
3) After 30 minutes from the start of the reaction, the electromagnetic ring of the magnetic ring reaction tube is switched between the reaction zone and the low temperature zone of the reaction tube main body 1 at a frequency of 75 s/time to adsorb and fix the produced modified nano triiron tetroxide. However, when the electromagnetic ring is energized, the residence time in both the reaction zone and the low temperature zone is 4 s.
4) The prepared precipitate is collected by centrifugation, washed and dried to obtain modified nano triiron tetroxide.
Using the above method, it is possible to partially reduce ferric iron to ferric iron using aniline monomers without adding additional substances, and the effect of triiron tetroxide At the same time, ferric and trivalent iron can catalyze the polymerization of aniline monomers to realize the preparation of triiron tetroxide/polyaniline composite nanomaterials, which continues after the initiation of the reaction. The modified triiron tetroxide generated in the magnetic field is magnetically attracted and moved to a low temperature region for short-term temperature difference switching. found to be beneficial in stabilizing the magnetic properties, at the same time, in subsequent use, the start-up of anaerobic reactors, because the modified triiron tetroxide has more stable magnetic and electrical conductivity, etc. Conductive nanomaterials are used as electron transfer mediators to enhance the catabolism of VFAs during acceleration, effectively avoiding large accumulations of VFAs in the reactor, buffering the pH and lowering the redox potential. It plays a role in promoting the growth of anaerobes, creates an environment that promotes the growth of anaerobes, strengthens and concentrates anaerobes that have the ability to directly transfer electrons between species, and increases the methane production rate of anaerobes.
Furthermore, the temperature of the low temperature zone is controlled at 105°C.
6 and 7, the magnetic ring reaction tube comprises a reaction tube body 1, an electromagnetic ring 2 slidably fitted in the reaction tube body 1, and an inner wall of the reaction tube body 1. a guide ring 3 for controlling the electromagnetic ring 2 which is slidably provided in the body, a drive component 4 which moves up and down in synchronization with the guide ring 3, a housing 5 which covers the drive component 4;
a pedestal 6 for supporting the drive component 4 and the reaction tube body 1;
7 and 8, the driving component 4 includes a driving motor 41, a driving gear ring 42, a screw nut and a first screw 43 rotatably mounted on the first bump 21 of the outer wall of the electromagnetic ring 2. , a screw nut rotatably provided on the second bump 31 on the inner wall of the guide ring 3 and a second screw 44, the first bumps 21 are provided on the lower end surface of the electromagnetic ring 2 in the circumferential direction at intervals of 40°. Nine sets of second bumps 31 are provided on the lower end surface of the guide ring 3 in the circumferential direction, nine sets are provided at intervals of 40°, and the first screw 43 and the second screw 44 are the first bumps 21 and the second screws 44 . The drive motor 41 is provided on the pedestal 6, the lower end of the first screw 43, the second screw 4
A first gear 45 and a second gear 4 are respectively located at positions corresponding to the drive gear ring 43 below 4.
The second gear 46 is connected to the lower end of the second screw 44 through the reaction tube body 1 through the shaft rod. However, the torsion directions of the first screw 43 and the second screw 44 are opposite.
As shown in FIG. 7, a seal cover 11 is provided on the top surface of the reaction tube main body 1, and a temperature control rod 12 extending into the reaction tube main body 1 is provided at the center of the seal cover 11. A heating plate 13 is provided on the inner bottom surface of the reaction tube 1, and a first temperature sensor for monitoring the low temperature zone and an air pressure sensor for monitoring the pressure inside the reaction tube main body 1 are provided on the inner bottom surface of the seal cover 11. , a second temperature sensor is provided on the inner bottom surface of the reaction tube body 1 for monitoring the reaction zone.
The above magnetic ring reaction tube can meet the technical requirements of the process of preparing modified nano triiron tetroxide, and at the same time, it is equipped with a set of driving motors 41 to combine other members of the driving component 4. Move electromagnetic ring 2 and guide ring 3 synchronously, step 3)
The above magnetic ring reaction tube reduces the difficulty of preparing the modified nano triiron tetroxide process, and significantly reduces the preparation cost of the modified nano triiron tetroxide.
The operating principle of the magnetic ring reaction tube is as follows. By controlling the rotation speed and time of the drive motor 41 by an external programmable PLC controller command, the residence time for moving the electromagnetic ring 2 and the guide ring 3 up and down along the reaction tube main body 1 is controlled, and the programmable PL
The C controller can be a commercially available Siemens miniature SR40 controller or any other commercially available controller that meets the control requirements of the device.
When the driving motor 41 rotates, it is connected to the driving gear ring 42 via the output shaft to rotate the driving gear ring 42. When the driving gear ring 42 rotates, the outer first gear 45 and the outer second gear 46 are respectively forward. , reverse rotation, and the different twisting directions of the first screw 43 and the second screw 44 cause the electromagnetic ring 2 and the guide ring 3 to move synchronously under the action of the corresponding rotating nut, at the same time to meet the requirements of synchronous movement. , considering the difference between the inner diameter and the outer diameter of the drive gear ring 42, the first gear 45 and the second gear 46 when the drive gear ring 42 rotates one turn.
It is necessary to ensure that the number of turns of rotation is the same.

Example 5
This example is basically the same as Example 4 except for the following, and the reaction temperature during preparation is different, specifically as follows. The magnetic ring reaction tube is heated to 180°C and reacted for 6 hours, and the temperature of the low temperature zone is controlled at 80°C.

Example 6
This example is basically the same as Example 4 except for the following, and the reaction temperature during preparation is different, specifically as follows. The magnetic ring reaction tube is heated to 200°C and reacted for 8 hours, and the temperature of the low temperature zone is controlled at 110°C.

Example 7
This example is basically the same as Example 4, except for the following, the aniline monomer and F
The addition ratio of e(NO ₃ ) _{3.9H 2} O is different, specifically as follows. The molar ratio of aniline monomer and Fe(NO ₃ ) _{3.9H 2} O is 1:0.45.

Example 8
This example is basically the same as Example 4, except for the following, the aniline monomer and Fe
The addition ratio of (NO ₃ ) _{3.9H 2} O is different and is specifically as follows. The molar ratio of aniline monomer and Fe(NO ₃ ) _{3.9H 2} O is 1:1.94.

Example 9
This example is basically the same as Example 4 except for the following, and the process parameters in step 3) are different, specifically as follows. 30 minutes after the start of the reaction, the electromagnetic ring of the magnetic ring reaction tube was switched between the reaction zone and the low temperature zone of the reaction tube main body 1 at a frequency of 45 s/time to adsorb and fix the modified nano triiron tetroxide produced, When the ring is energized, the residence time in both the reaction zone and the cold zone is 3s.

Example 10
This example is basically the same as Example 4 except for the following, and the process parameters in step 3) are different, specifically as follows. 30 minutes after the start of the reaction, the electromagnetic ring of the magnetic ring reaction tube was switched between the reaction zone and the low temperature zone of the reaction tube main body 1 at a frequency of 90 s/time to adsorb and fix the modified nano triiron tetroxide produced, and When the ring is energized, the n residence times are both 5 s in the reaction zone and the cold zone.

Experimental Example Taking Example 1 as an example, the effect of the addition of conductive nanomaterials _on anaerobic reactor start _- up was investigated.
Chemical Technology Co. , Ltd and has a nominal particle size of 20 nm in the technical specifications. SiO ₂ NPs used in the experiments are from Shanghai Alad
din Biochemical Technology Co. Co., Ltd., with a nominal particle size of 20-30 nm. The inoculated sludge used in the experiment was collected from the sludge thickening tank of Nanjing Jiangxinzhou Sewage Treatment Plant, and the sludge MLSS after passing through a 35-mesh sieve to remove large particles was 24.53±0.07 g/L. , MLVSS/MLSS=0.47.
Residual sludge (AS) from municipal sewage treatment plants, Fe ₃ O ₄ NPs composite sludge (Fe ₃ O ₄ NPs
@As), SiO ₂ NPs composite sludge (SiO ₂ NPs @AS) (order numbers R0, R1, R2
) separately and started running under the same experimental conditions, three EGSB reactors were each inoculated with equal amounts of blank inoculum sludge, Fe ₃ O ₄ NPs composite sludge, SiO ₂ NPs composite sludge,
The final MLVSS is 3 g/L and the reactor temperature is controlled at 35±1°C. The reactor was started in simulated wastewater operation. Sodium propionate (C ₃ H ₅ O ₂ Na) as carbon source, ammonium chloride (NH ₄ Cl) as nitrogen source, dipotassium phosphate/potassium dihydrogen phosphate (K ₂ HPO ₄ /KH ₂ PO ₄ ) was used as the phosphorus source to prepare simulated wastewater. Waste water COD:N:P
= 200:5:1 and 1 L COD is 5000 mg/L.
921 g, 0.549 g of potassium dihydrogen phosphate, 0.1 g of magnesium chloride, 0.05 g of calcium chloride are weighed and dissolved in 500 mL of water, and 1 mL of trace element complex solution is added,
Set the volume to 1L. It should be prepared once and kept at room temperature for 2 days and re-prepared the next day.
The three reactors were operated under the same conditions, with an operating temperature of 35±1° C. and an initial reactor start-up load of 1 k.
g/(m ³ d), inflow COD concentration 5000 mg/L, HRT controlled at 120 hours, until the reaction operation stabilizes (COD removal rate stabilizes at 85% or more, relative deviation is 3% or less) and the stabilization time is 5 days or more), increase the inflow COD or shorten the HRT to increase the load to 1.5 to 2 times the original. According to the different OLR of the reactor, the reactor start-up process is defined by Sta
ge I: OLR is 1-4 kg/(m ³ d), Stage II: OLR is 8-16 k
g/(m ³ ·d), Stage III: Divided into three steps with OLR reaching 20 kg/(m ³ ·d). Finally, the reactor was operated for 165 days and the influent COD was 12500 m.
g/L, HRT 15 hours, OLR 20 kg/(m ³ ·d). The reactor start-up parameters and loading process are detailed in Table 1.
Table 1 Table of reactor operating conditions during start-up period

* COD stands for chemical oxygen demand, HRT stands for hydraulic residence time, OLR stands for organic load factor, F stands for ratio of circulating water to influent, Up-flow velocity stands for rate of rise. show.

Next, conduct the following investigations.
1. Effects of addition of Fe ₃ O ₄ NPs and SiO ₂ NPs on the performance of start-up staircase system Activated sludge (AS), Nano triiron tetroxide composite anaerobic activated sludge (F
e ₃ O ₄ NPs@AS), nano-silicon dioxide composite anaerobic activated sludge (SiO ₂ NPs@AS) inoculated reactors under different load steps to monitor and analyze the effluent COD.
As shown in Fig. 1, ₃ inoculated with AS, _Fe3O4NPs @AS and _SiO2NPs @AS to investigate the influence of conductive nanoparticles on the OLR resistance during start-up of the anaerobic EGSB reactor. Monitor and analyze effluent COD, methane production rate and pH at different loading stages of one reactor. The effluent COD concentrations of the three EGSB reactors (R0, R1 and R2) showed different downward trends in the first few days, and on the 15th day, the effluent COD concentrations of R0, R1 and R2 were 88.85±29.10 mg, respectively. /L, 85.37±25.78 mg/L and 9
2.34±13.15 mg/Ld, compared to low OLR wastewater (1 kg COD/(m ³ d
)) have similar post-processing efficiencies. Period 16-129 days, R0, R1 and R2
Although the effluent COD concentration of the effluent COD concentration changes with increasing OLR, the consistency of the effluent COD removal efficiency is second
Continuing to the end of the staircase, the R0 effluent COD removal efficiency always exceeds 89.12±0.19%,
The effluent COD removal efficiency of R1 is 90.79±0.08% and the effluent COD removal efficiency of R2 is 83.88±0.19% (excluding day 20) (FIG. 1B). The higher COD removal efficiency appeared after the impact of OLR, and the stability of the three systems improved after the sludge was further adapted and matured. Specifically, on day 54, the HRT of the anaerobic reactor was further reduced to 15 hours and the influent COD
Increasing the concentration to 5000 mg/L increased the OLR to 8 kg COD/(m ³ ·d). Over the next few days, effluent COD concentrations in R0, R1 and R2 were 748.89±10, respectively.
. 10 mg/L, 400.73±5.91 mg/L and 266.92±9.23 mg
/L (60 days) to 399.17±42.34 and 74.09±10.58 169.
It decreased to 34±3.02 mg/L (day 62), indicating that the Fe ₃ O ₄ NPs@AS system's resistance to impact and stability of the recovery process were superior to the other systems. this is,
Anaerobic microorganisms attach to the nanoparticles by increasing the secretion of EPS, which not only prevents the nanoparticles from passing through the cell membrane, but also utilizes the aggregation of the nanoparticles attached to the AS to facilitate the granulation of activated sludge. and increase the biomass in the reactor. Moreover, Fe ₃ O ₄ NPs
The conductivity of s can be used as a conductor between acetogens and methanogens, facilitating direct electron transfer and enhancing anaerobic metabolism of VFAs. The influent COD concentration in the third step was further increased to 12500 mg/L while the HRT was 15 hours and the reactor OLR was 20.
kg COD/(m ³ ·d) was reached. Compared to R0 and R2, R1 showed a very different response to the influence of OLR, with R1's process stability being restored for 7 days (effluent CO
D concentration drops from 394.82±21.23 mg/L to 247.52±54.08 mg/L), R0 and R2 tend to collapse as the effluent COD concentration rises sharply. Specifically, the effluent COD concentration of R1 was maintained at about 209.17±15.79 mg/L on day 160 (removal rate was 98.22%), and the effluent COD concentrations of R0 and R2 were each 478.6.
6±1.06 mg/L and 1312.87±9.55 mg/L (day 131) sharply to 5996.47±12.33 and 6381.27±51.8 mg/L (day 160) increased to In other words, the addition of Fe ₃ O ₄ NPs under high OLR promotes the decomposition of organic matter and improves the operational stability of the anaerobic reactor.
As shown in Fig. 1C, the methane production rates of R0, R1 and R2 (first tier) show slight differences and show the same increasing trend with increasing OLR, a limited matrix indicating that the three systems are sufficiently May be leveraged and transformed. On the second staircase, the OLR is 8 kg C
There was a significant difference in the methane production rates of the three reactors when the OD/(m ³ ·d) was increased. 6
On day 3, R0, R1 and R2 methane production rates of 13.02±0.88 L/d respectively
, increased to 17.14±2.62 L/d and 12.55±0.76 L/d. The methane production rate of R1 was 31.64% and 36.57% higher than R0 and R2. _Fe3
The self-conductivity of O ₄ NPs can accelerate electron transfer between acetogens and methanogens, promoting substrate metabolism and thereby improving methanogenic performance of anaerobic sludge. In particular, by adjusting the influent COD concentration, the reactor OLR was reduced to 16 kg COD/(m ³
d), the methane production rate of R1 steadily increased by 40 L/d at 120 days, while R0 and R2 were delayed by 15 and 13 days to reach this production rate, respectively. During the process of resisting high OLR, as can be seen by comparing the R1 and R2 data, the anaerobic sludge granulation caused by the aggregation of nanomaterials is gradually replaced by the interspecies electron transfer effect, thereby Promotes substrate metabolism. Therefore, if the OLR is further reduced by 20 kg COD/(m
³ d) When increased to (step III), the methane production rates of R0, R1 and R2 for 5 days were 44.45±1.12 L/d, 49.63±1.13 L/d and 39.88 respectively. ±
increased to 2.64 L/d. After that, the methane production rate in the R1 reactor decreased slightly to about 43
L/d, but the methane production rate of the R0 and R2 reactors dropped sharply to about 26 L/d.
/d and 23 L/d.
During the process of anaerobic digestion, an appropriate pH range facilitates microbial metabolism. In the first and second steps (FIG. 1D), the overall pH value is kept within a suitable range (7.2-7.5), conducive to vigorous performance of anaerobic methanogens. In the third step, p
The H value also decreased and the pH value of the R1 reactor was kept at a relatively high level, about 6% higher than R0 and R2, but the addition of _Fe3O4 NPs stabilized the pH value during the _EGSB start-up process. showed that it is possible to As analyzed from the present data, the accumulation of volatile fatty acids (VFAs) can be caused by slightly lower R0 and R1 system pH values. More data, such as VFAs, need to be mined to confirm previous speculations.

2. Metabolic characteristics of VFAs VFAs released at the start-up stage of the three reactors were investigated (Fig. 2). As a result, VFAs in the reactor were mainly acetate and propionate, and their concentrations were calculated by equivalent COD (acetate equivalent 1.07 g COD/g, propionate equivalent 1.51 g COD/g ). During the start-up process, under the influence of high OLR, the VFAs in the three reactors had similar change characteristics (i.e., rapid accumulation of propionate and acetate) with increasing OLR, but that of propionate and acetate increased. There is a large difference in the concentration ratio. In short, in the first step, the reactor has a low OLR (8
kg COD/(m ³ d)), the concentration of propionate in the three reactors (COD of about 70 mg/L) is several times higher than that of acetate (COD of about 20 mg/L). was only expensive. However, on day 57 of the second step, when the OLR increased to 8 kg COD/(m ³ d) (Fig. 2A), the concentrations of propionate and acetate in R0 increased to 345.01
mg/L and 97.11 mg/L with no significant accumulation of propionate and acetate in R1. The corresponding propionate concentration in R2 was 200 mg/L on day 57, similar to R1, but on day 61 this value increased to 700 mg/L. the next stair (
In step 3), the OLR reached 20 kg COD/(m ³ ·d) with significant propionate accumulation in the R0 and R2 effluents. On day 152, the R0 propionate concentration was 3
712.42 mg/L and the R2 propionate concentration was 4645.64 mg/L.
However, in R1, there was no significant accumulation of VFAs in the sewage, especially the concentration of propionate was 154.10 mg/L.
Therefore, the addition of Fe ₃ O ₄ NPs enhances the stability of the recovery process, especially under the influence of high OLR, as can be seen from the VFAs situation in the three reactors. This is because propionate can be effectively converted to acetic acid as a core metabolite of synthetic metabolism during the anaerobic digestion process.
It has long been thought that accumulation of VFAs is toxic to anaerobic methanogens. Therefore, further consumption of acetic acid biotransformed by propionic acid is mainly Fe ₃ O
This may be due to the fact that 4NP facilitates information exchange and material transduction between anaerobic microbial _cotrophic communities in a more direct interspecies electron transfer mode _than electron shuttles (H2 or formate). Therefore, the energy allocated for the decomposition of VFAs is optimized to provide favorable living conditions for methanogens. In fact, the activated sludge granulation process further shortens the electron transfer distance between acetogens and methanogens. Based on the above discussion, it was found that the provision of electrically conductive material provides an alternative electron transfer pathway for the anaerobic methanogenesis system during the start-up phase of treating highly loaded wastewater, allowing the system to stabilize. ensure that it is in good condition.

3.Electron transport system activity Electron transport system (ETS) activation detection is not only used to reflect potential respiratory capacity, but also as an indicator of the metabolic activity of organisms in aerobic and anaerobic environments. used. INT-ETS indexes on days 30, 50, and 150 are established in three reactors to determine ETS activity with and without NPs. As can be seen from the results (Fig. 3A), the control set reactor (R0) and the _Fe3O4 NPs ₍ R1) or SiO
The INT-ETS of reactors supplemented with ₂ NPs (R2) differ greatly at different times. R.
Overall INT-ETS of 1 was much higher than R0 and R2, 256.98 ±
26.33 μg/(g min), 477.44±14.73 μg/(g min) on day 50
min) and reached 883.99±106.21 μg/(g·min) on day 150.
The corresponding values for R0 were 204.76±7.61 μg/(g min) (day 30), 19
1.19±26.63 μg/(g min) (day 50) and 525.94±32.9
0 μg/(g min) (day 150) and the corresponding value for R2 was 168.07±1
7.11 μg/(g min) (day 30), 262.68 ± 45.59 μg/(g m
in) (day 50) and 381.96±39.65 μg/(g·min) (day 150). As can be seen from the results compared to R0 and R2, after adding _Fe3O4 NPs ₍ R1), the electron transfer efficiency between acetogens and methanogens was 68.7, respectively.
8% and 131.44% improvement, and the addition of conductive materials can cause DIET, a more efficient electron transfer pathway, so electrons transfer directly from the electron donor to the electron acceptor. Therefore, under the influence of high OLR, well-conducting Fe ₃ O ₄ NPs can be used as conductors between anaerobic microorganisms to realize DIET, promoting the metabolism of VFAs and the accumulation of methane.
Further evidence for DIET is illustrated by the CV curve, the movement of redox peaks can characterize the electron transfer capacity between cotrophic bacteria. Forward scan results showed that under the same voltage, R1 had an enhanced oxidation peak at 0.246 V, and the current was 1.4 mA (Fig. 3B), about 76.59% higher than R0 and 61.87% higher than R2. it was high. As can be seen from the results, the long-term exposure of Fe ₃ O ₄ NPs makes the anaerobic sludge system have stronger electron transfer ability, especially under high OLR. To further investigate the contribution of Fe ₃ O ₄ NPs conductivity to the electron transfer capability of the system, the same Fe ₃ O ₄ NPs as R1 are exposed and temporarily added to R0 before the measurements. Scan the CV curves under the same conditions. As can be seen from the results,
The addition of Fe ₃ O ₄ NPs, R0 improved the electron transfer ability of the sludge (from 0.79 to 1.
0 mA) is 40.0% lower than R1. _In addition to the interspecies electron transfer effect induced by the conductivity of _Fe3O4NPs , other factors that can improve the efficiency of electron transfer, such as DI
There should be an enrichment of microorganisms that can participate in ET or an increase in electron transfer mediators in extracellular secretions. This also confirmed why all three reactors showed better organic load removal rates in the second stage.

4. Anaerobic sludge EPS analysis EPS secreted by microorganisms includes proteins (Proteins, PN), polysaccharides (
Polysaccharides, PS), humic substances
, HS), nucleotides and lipids, and relative content changes of PN and PS are related to external environmental conditions.
EPS is divided into loose type EPS (Lose-bond EPS, LB-EPS) and compact type EPS (Tight-bond EPS, TB-EPS). An analysis of the EPS components is shown in FIG. As can be seen from the results, TB-EPS is a major component of the three-dimensional matrix composed of extracellular secretions, and its content fluctuates due to external environmental interference. Whether it is LB-EPS or TB-EPS, the content of PN increases significantly with the increase of OLR, while PS always remains at a low level. In particular, TB-EPS had PN content in the three reactors ranging from about 15 mg/g VSS (day 65) to over 70 mg/g VSS (day 114), which is due to the impact of high OLR, making the system relevant. It increases the protein content to resist metabolic stress caused by environmental changes, and further maintains the structural stability and metabolic activity of granular sludge. PS played an important role in maintaining sludge morphology and preventing sludge floc dispersion caused by changes in hydraulic load, but the PS content in the three reactors did not change much during the start-up process. and its concentration is LB
-EPS and TB-EPS remained at approximately 2.5 mg/g VSS. On day 65, the total amount of EPS in reactor R1 was the highest, followed by R2, which was the initial stage of nanoparticle addition, where the microorganisms increased secretion of EPS and the nanoparticles crossed the cell membrane. has been shown to have the potential to prevent On day 152, total EPS decreased and EPS secretion in R0 and R2 became lower than in R1, indicating that a high OLR of 20 kg COD/(m ³ d) exceeded the permissible limits of R0 and R2, propionic acid Salt accumulated and reduced the COD removal rate by about 50%. This may be based on two approaches taken by microbial systems, one is that high OLR (20 kg COD/ ⁽ m3 d)) greatly challenges the impact resistance of granular sludge;
thinning the three-dimensional matrix of R0 and R2, _two of which the conductive _Fe3O4 NPs facilitate electron transfer between synthetic communities, effectively avoiding the accumulation of propionic acid in the system;
It is to lower metabolic pressure. Therefore, the _EGSB system via _Fe3O4 NPs has more options when faced with the effects of high organic loading, i. select. High OLR and Fe
It cannot be denied that 3O4NP may induce EPS to secrete some electron transfer mediators involved in DIET, such as cytochrome c and quinone compounds, which suggests that R1 It is reasonable to have a higher electron transfer efficiency than the R0 system.

5. Microbial community composition Genomic DNA of day 0, day 50, and day 150 sample sludge was analyzed to describe the evolutionary characteristics of the bacterial community under the influence of OLR during start-up of the three EGSB reactors. Separated and analyzed by high-throughput sequencing. As can be seen from FIG. 5A, on day 150,
Syntrophobacter, f_Spirochaetaceae, f_Syner
Sequences most similar to gistaceae and f_Anaerolineaceae species accumulated significantly in the three reactors. Specifically, on day 150, Syntrophoba
The relative abundance of cter reached 32.03%, with R0 (20.35%) and R2 (27.
80%). Since Syntrophobacter is essential for the synthesis and oxidation of propionate and butyrate, it shares electrons with Methanoseacina. In R0, R1 and R2, the relative abundance of f_Spirochaetaceae was 16.71
%, 17.41% and 16.75%. accumulating microorganisms capable of transferring extracellular electrons associated with f_Synergistaceae to the Fe(III) oxide or electrode,
Its abundance is 17.56%, 7.19% and 8.17 in R0, R1 and R2 respectively
% reached. Geobacter, as a quintessential synthetic bacterium, has been shown to be able to share electrons with electron acceptors via DIET, although its absence does not significantly reduce the efficiency of electron transfer. This may realize information exchange and substance conversion between cotrophic microorganisms under high OLR due to the presence of alternative electron donors such as f_Synergistaceae. f_Anaerolineaceae is characterized by the fermentation and metabolism of hydrocarbons, and its filamentous morphology tends to cluster together with Methanosaeta and cooperate with each other, thus helping to shorten the electron transfer distance between them.

As shown in Fig. 5B, under high OLR influence (day 150), Methanosaeta was the most abundant archaea, with abundance reaching 60.58% at R1, R0 (54.59%) and R2 ( 57.22%). Next are the genera Methanobacterium and Methanolinea. Recently, G. It has been discovered that metallireducens undergo direct electron transfer with methanogenic organisms (eg, Methanosaeta species), the latter accepting electrons through the DIET process and reducing carbon dioxide to methane. Therefore, mutual nutrition and co-metabolism may have played an important role, suggesting that Methan
osaeta has been shown to be able to directly exchange electrons with biogenic bacteria. M.
Ethanobacterium has been used as a model for H2 _- mediated interspecies electron transfer, DIET
, indicating that the distribution of DIET's potency in methanogens is much broader than previously thought. Overall, with a procedural increase in external load during the start-up phase, anaerobic digestion systems appear more likely to regulate bacterial community structure to maintain a steady state of the system, with specific functional bacteria and archaea. It does more than just increase the abundance of bacteria. However, once the OLR reaches a certain threshold (above 20 kg COD/(m ³ d)), the performance of the anaerobic digestion system gradually declines and cannot be reversed by bacterial community abundance alone. For example, f_Spirochaetaceae, f_Synergistaceae
and Methanolinea genera abundance may indicate that IHT is the predominant mode of electron transfer. However, under high OLR conditions, IHT-based anaerobic digestion systems perform poorly, causing a suppressed pseudo-steady state, i.e., blocked electron transfer between acetogens and methanogens via the IHT. . _Fe3
DIET mediated by O ₄ NPs promotes the efficiency of electron transfer between acetogens and methanogens, attenuating the impact of high OLR on the anaerobic digestion system, resulting in good COD removal and methanogenesis rates. .

At the same time, the following experimental investigations are currently being conducted to further verify the technical effects of various embodiments.
1) Influence of different parameters on anaerobic reactor start-up effect
In III) the influent COD concentration is further increased to 12500 mg/L and the HRT is maintained at 15 hours.
Example 1: R1 effluent COD concentration at day 160 is about 209.17±15.79 mg/L
maintained at
Example 2: Reactor R1 effluent COD concentration on day 160 is about 231.05±12.73 m
was maintained at g/L.
Example 3: Reactor R1 effluent COD concentration at day 160 is about 229.42±13.11 m
was maintained at g/L.
Therefore, as can be seen from the comparison, in Examples 2 and 3, the outflow COD was higher than in Example 1, so that the starting effect of the anaerobic reactor of Example 1 was superior.
2) Effect of different conductive nanomaterials on anaerobic reactor start-up effect
In III) the influent COD concentration is further increased to 12500 mg/L and the HRT is maintained at 15 hours.
Example 1: R1 effluent COD concentration at day 160 is about 209.17±15.79 mg/
maintained at L.
Example 4: Reactor R1 effluent COD concentration on day 160, about 191.34±14.75 m
was maintained at g/L.
At the same time, taking Example 4 as an example, Fe(NO ₃ ) _{3.9H 2} O was dissolved in absolute ethanol, the aniline monomer was dissolved in absolute ethanol, and the aniline monomer and Fe(NO ₃ ) were dissolved.
The molar ratio of _{3.9H 2} O is 1:1.45, then put into the magnetic ring reaction tube, flow into the magnetic ring reaction tube below the height of the magnetic ring, and then into the magnetic ring reaction tube. Filled with nitrogen gas so that the pressure is 2.5 MPa, the magnetic ring reaction tube is heated to 195 ° C. and reacted for 7 hours, the prepared precipitate is collected by centrifugation, washed and dried, and modified Nano triiron tetroxide is obtained and the prepared modified nano triiron tetroxide is taken as a control.
Control Example: Reactor R1 effluent COD concentration on day 160, about 203.17±13.67 mg
/L.
Therefore, as can be seen by comparison, the use of the modified nano triiron tetroxide in Example 4 resulted in a relatively lower outflow COD than the use of the nano triiron tetroxide in Example 1, and the magnetic ring reaction tube Due to the small effect on the anaerobic reactor start-up effect of the modified nanotriiron tetroxide not treated with
The start-up effect of the anaerobic reactor of Example 4 was better.
3) Effect of Different Temperature Parameters on Anaerobic Reactor Startup Effect Taking Examples 4, 5 and 6 as an example, using the method described above, the third step of reactor startup (Stag
In e III) the influent COD concentration is further increased to 12500 mg/L and the HRT is maintained at 15 hours.
Example 4: Reactor R1 effluent COD concentration on day 160, about 191.34±14.75 m
was maintained at g/L.
Example 5: Reactor R1 effluent COD concentration at 160 days, about 198.71 ± 15.12 m
was maintained at g/L.
Example 6: Reactor R1 effluent COD concentration on day 160, about 200.53±15.17 m
was maintained at g/L.
Therefore, it can be seen by comparison that the use of different temperature parameters in Examples 5 and 6 has a certain impact on the use effect of the prepared modified nano-triiron tetroxide, and the temperature parameter used in Example 4 is Relatively better.
4) Effect of Different Mixed Addition Ratios on Anaerobic Reactor Startup Effect Taking Examples 4, 7, and 8 as an example, using the method described above, the third step of starter start-up (Stag
In e III) the influent COD concentration is further increased to 12500 mg/L and the HRT is maintained at 15 hours.
Example 4: Reactor R1 effluent COD concentration on day 160, about 191.34±14.75 m
was maintained at g/L.
Example 7: Reactor R1 effluent COD concentration on day 160, about 199.81 ± 14.23 m
was maintained at g/L.
Example 8: Reactor R1 effluent COD concentration on day 160, about 196.34±13.76 m
was maintained at g/L.
Therefore, it can be seen by comparison that the use of different mixing addition ratios in Examples 7 and 8 has a certain effect on the use effect of the prepared modified nano triiron tetroxide, and the use effect of Examples 4 and 8 is It is relatively better, but it can be selected according to needs, considering factors such as actual production costs.
5) Influence of Different Magnetic Ring Reactor Tube Parameters on Anaerobic Reactor Starting Effect
In e III) the influent COD concentration was further increased to 12500 mg/L and HRT was maintained at 15 hours.
Example 4: Reactor R1 effluent COD concentration on day 160, about 191.34±14.75 m
was maintained at g/L.
Example 9: Reactor R1 effluent COD concentration at 160 days, about 195.81 ± 14.43 m
was maintained at g/L.
Example 10: Reactor R1 effluent COD concentration at day 160 is about 194.77±14.89
maintained at mg/L.
Therefore, it can be seen by comparison that the use of different magnetic ring reaction tubes in Examples 9 and 10 has a certain effect on the use effect of the prepared modified nano triiron tetroxide, and the use effect of Example 4 is relatively superior in terms of

Claims (7)

A method of facilitating start-up of an anaerobic reactor using conductive nanomaterials, comprising:
Conductive nanomaterial composite anaerobic activated sludge is prepared, the prepared conductive nanomaterial composite anaerobic activated sludge is inoculated into an anaerobic reactor at a volume concentration of 5 to 18 gVSS / L, and the anaerobic reactor including the step of initiating
The method for preparing the conductive nanomaterial composite anaerobic activated sludge comprises:
adding the conductive nanomaterials to deionized water and ultrasonically dispersing them to prepare a conductive nanomaterial dispersion solution;
adding the prepared conductive nanomaterial dispersion solution to anaerobic activated sludge and stirring for 22 hours to obtain conductive nanomaterial composite anaerobic activated sludge;
A method for promoting start-up of an anaerobic reactor based on conductive nanomaterials, comprising: The conductive nanomaterial is nano triiron tetroxide, and the particle size of the nano triiron tetroxide is 20 to 30.
nm,
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that: The conductive nanomaterial is modified nano triiron tetroxide, and the method for preparing the modified nano triiron tetroxide comprises:
1) The molar ratio of aniline monomer and Fe(NO ₃ ) _{3.9H 2} O is 1:0.45-1.94
dissolving Fe(NO ₃ ) _{3.9H 2} O in absolute ethanol and dissolving the aniline monomer in absolute ethanol such that
2) Next, after adding nitrogen gas into the magnetic ring reaction tube so that the filling amount in the magnetic ring reaction tube is equal to or less than the height of the magnetic ring, the pressure becomes 2.5 MPa. and heating the magnetic ring reaction tube to 180-200° C. to react for 6-8 hours;
3) After 30 minutes from the start of the reaction, the electromagnetic ring (2) of the magnetic ring reaction tube is switched between the reaction zone and the low temperature zone of the reaction tube body (1) at a frequency of 45 to 90 s/time to produce modified nanotetraoxide. Adsorbing and fixing triiron, when the electromagnetic ring (2) is energized, the residence time in the reaction zone and the low temperature zone is 3-5 s, and the temperature of the low temperature zone is controlled to 80-110° C.;
4) collecting the prepared precipitate by centrifugation, washing and drying to obtain modified nano triiron tetroxide;
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that: The conductive nanomaterial composite anaerobic activated sludge has a dry weight ratio of 0.03 to 0.15:1 between the conductive nanomaterial and the anaerobic activated sludge.
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that: When the anaerobic reactor is started, the pH is controlled to 6.7-7.5, the temperature is controlled to 27-36° C., and the COD:N:P is 400-200 during the start-up process of the anaerobic reactor. : 7 to 3:1,
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that: The anaerobic reactor is any one of a normal digester, an anaerobic catalytic digester, an ascending anaerobic sludge bed, and an anaerobic particulate sludge expansion bed, and the anaerobic activated sludge is flocculated sludge , in particulate sludge,
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that: The stirring method is to culture for 22 hours with mechanical stirring and anaerobic culture at a stirring speed of 120 rpm.
The method of accelerating start-up of an anaerobic reactor based on conductive nanomaterials according to claim 1, characterized in that:

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