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During the fuel injection stage of the FCC unit, the connection between the reaction and the compressor is very important, which is the key to ensure the control of the reaction pressure and work without flaring at the inlet of the compressor. Due to the many interference factors during the start-up fuel injection process, the operation is unstable, it is necessary to discharge flaring at the compressor inlet several times to control the reaction pressure, so that a large number of gas-rich components are discharged to the flaring system for combustion. Through practical exploration, combined with the performance parameters of the compressor, several ways of start-up without flaring are compared, and finally the shortest way of using dry gas and injection of feedstock is chosen to start the unit. By formulating detailed start-up plans and operating principles, optimizing the process, accurate control of start-up pressurized dry gas, reaction injection amount, compressor speed, compressor anti-surge amount and other parameters can be carried out in the actual start-up process. The goal of without flaring during the start-up process is achieved, effectively reducing environmental pollution, avoiding material loss during the start-up process, and realizing green environmentally friendly start-up. [ABSTRACT FROM AUTHOR]

[Introduction] The gas turbine generator set (GE-PG9351FA) with a DLN2.0 + burner and a designed NOx emission concentration of 50 mg/m3 is used in a gas turbine power plant. During the warm-up periods, the generator set emitted a large amount of yellow smoke, which violates provisions stipulated in the "Emission Standard for Air Pollutants from Thermal Power Plants" (GB 13223—2011) and is complained by the surrounding residents. According to the new emission regulations for environmental protection in Jiangsu, starting from January 1, 2023, the converted NOx emission average throughout the operation period should be less than 30 mg/m3. In order to meet this requirement and reduce the emission of yellow nitrate smoke during start-up, the renovated SCR denitration technology for the flue gas of the HRSG (Heat Recovery Steam Generator) is adopted. Data simulation, deduction, analysis and summarization of various indicators are conducted during the start-up process to refine a reasonable startup operation method. [Method] To validate the feasibility of this method, the power plant conducted multiple peak shaving start-up process operation tests. Based on the actual NOx emission characteristics, adjustments were made to the start-up point, gas turbine load control, and input nodes for the SCR system in the operation method. This process resulted in an optimized operational strategy. [Result] The test results show that by optimizing the SCR denitration system input point, gas turbine start-up point and warm-up load after grid connection, the converted NOx emission average throughout the operation period is less than 30 mg/m3, and the phenomenon of yellow nitrate smoke disappeared. [Conclusion] This strategy is based on the characteristics of NOx and yellow nitrate smoke emission during the gas turbine start-up process. Afterward, through data deduction and numerous experiments for validation, it can provide direct guidance for reducing yellow nitrate smoke emission during the start-up process of similar gas turbines. Additionally, it can serve as an analytical reference for controlling NOx emissions during peak shaving operations in gas turbine power plants.

Copyright of Southern Energy Construction is the property of Southern Energy Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Corrosion & Protection in Petrochemical Industry is the property of Corrosion & Protection in Petrochemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Anammox process has attracted widespread attention because of its high denitrification efficiency, no need for oxygen supply, no need for organic carbon sources, less sludge production, small process area and low capital investment. The denitrification characteristics and influencing factors (temperature, dissolved oxygen, pH value, metal ions, light, and ammonia nitrogen concentration) of Anammox bacteria were reviewed. At the same time, the latest research progress of starting Anammox process using MBR, SBR, SBBR and UASB reactors at home and abroad is summarized, as well 血 the actual engineering application of Anammox in China. In ohIet to provide reference for the practical engineering application of Anammox process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Management & Business Research (2521-4306) is the property of Chinese Management Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The start-up and operation of 0.52 MM TPY xylene separation unit in SINOPEC Tahe petrochemical Co., Ltd. are introduced. By adding temporary process and optimizing the constant temperature operation of xylene tower in time, the xylene tower can start smoothly and safely without C8 aromatics. The deviation between actual operation data and design data of the reformate fractionator during start-up period is analyzed, and the solution is put forward. The FHDO technology is used to remove olefins from the reformate. The operation is simple, the aromatics loss is small, and the bromine index of the mixed xylene decreases obviously. The unit has passed 100% load calibration, the yield of the mixed xylene and the energy consumption of the unit are better than the design value, and the quality of the mixed xylene meets the requirements. [ABSTRACT FROM AUTHOR]

The cryogenic loop heat pipe is a high-efficiency two-phase heat transfer device that is commonly used in space thermal control systems. In order to investigate the suitable working fluids for LHP in 180-230 K for space exploration applications, the effects of working fluids on the operating characteristics including start-ups, responses of the operating temperatures to the heat load rise, and thermal resistances of the LHP at steady states were researched by employing ethylene, ethane and propylene as fluid candidates. The experimental results and analysis showed that by controlling the temperatures of the evaporator and the compensation chamber at least 10 K below the critical temperatures of the fluids, the LHP achieved successful start-up with heat loads of 5 W. With approximate evaporator temperatures before the start-up, the start-up temperature rise were both within 2 K for the ethane and propylene charged LHP, the start-up time of the ethane charged LHP was less than that of the propylene charged one, and the latent heat and liquid viscosity of working fluids were largely responsible for the differences in the start-up time. The effect of working fluids on the responses of the LHP operating temperatures to the heat load rise was not obvious. The evaporator temperatures decreased and then increased with the rising heat load. The lowest evaporator temperatures occurred with heat loads of 20-30 W, and the time for the LHP to reach the new steady-state decreased with the heat load rise. The pressure drops of the working fluids in the external loop accounted for the significant differences among the heat transfer thermal resistances of the LHP at steady states, and the vapor phase pressure drops took the majority part of the external pressure drops. The smaller vapor pressure drop led to the smaller thermal resistance. The vapor pressure drops of the ethylene charged LHP were less than that of the ethane and then the propylene charged LHP with the same heat loads, and the vapor pressure drops for all three fluids decreased with the increasing temperature. Correspondingly, the thermal resistances of the ethylene charged LHP were less than that of the ethane and then the propylene charged one, all thermal resistances decreased with the rising temperature. The smallest thermal resistance obtained experimentally was 0.21 K/W. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the current start-up sand table experimental system, the monotonous financing way and the fixed lending interest rate for all enterprises comply with neither the real market fluctuations nor the running team changes during the operation, which is not propitious for sand table simulation. In this paper, we analyze the influence of the short-term floating interest rate towards the enterprise operation based on the short-term lending interest rate in the financing part of the start-up sand table experimental rules. The empirical results reflect that the short-term interest rate changes effectively according to the operation situation, leading to fluctuations on profitability and cash flow under the short-term floating interest rate rules. Thus it requires a better command of long-term operation plan and financial prediction to simulate the enterprise operation more effectively under the new rule, to enhance the experiment teaching of start-up sand table. Furthermore, we provide concrete examples for the dynamic design of the start-up sand table experimental rules to reform and explore the novel start-up sand table experimental system. [ABSTRACT FROM AUTHOR]

To shorten the residence time of the H2/O2 interface and restrict the start-up voltage of the stack during the start-up process of a proton exchange membrane fuel cell(PEMFC),the effect differences of direct start-up,hydrogen purging time and auxiliary load current on the performance of PEMFC were studied by experiment. A fuel system start-up control strategy was proposed which combines hydrogen-purging the anode with starting the auxiliary load current. Experimental results prove that the start-up control strategy limits the start-up voltage of the fuel cell,shortens the residence time of the H2/O2 interface during the start-up process of the stack,and is conducive to improve the single-battery voltage balance. So it is a kind of effective PEMFC start-up control strategy.

Anammox is an efficient nitrogen removal process, but it is difficult to start-up and operate, and ananammox reactor is the efficient way to resolve this problem. The start-up of anammox reactor by upflow anaerobic filter was studied. Denitrifying sludge, anaerobic sludge, and mixed sludge was inoculated on the packing materials, respectively and an autotrophic denitrification condition was provided by the simulated wastewater influent. Along with the gradual increase of matrix concentration and hydraulic load, the microflora was converted to the anaerobic ammonium oxidation(anammox)reaction. The results showed that the anammox reaction could be started by all the three sludge, and the time of start-up of denitrifying sludge, anaerobic sludge, mixed sludge was 42, 54 days and 45 days, respectively. The best result was that inoculated with denitrifying sludge with 82.2% of the total nitrogen removal rate, which started-up quickly and nitrogen was removed efficiently. Double packing effectively improved the stability of anammox process in the reactor, in which the suitable influent concentration loading for the anammox bacteria was 270 mg·L-1 and 360 mg·L-1 for ammonia nitrogen and nitrite nitrogen, respectively, and the COD concentration could not be more than 150 mg· L-1. Furthermore, there was a coexist-effect for anaerobic ammonia oxidation and methanation in this reactor system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The "Innovation, Start up and Career Service" program is based on the needs of college students innovation, start-up and job hunting. Utilizing an 020 model, the program helps providing train, consultating, testing and incubation services for college students. The program will set up virtue training station of starting camp, and training camp. The training camp simulates a practical channel to the career and start-up services. The career overview camp, simulating interview camp, intern camp and job prep camp will help students transiting smoothly from campus to job market and career development. The four stage, i. e., start-up overview camp, start-up training camp, start-up practice camp and start-up incubation camp will serve the needs for students who are interested in start-up busines. The career services and start-up service virtual camps utilize cloud computing technology to create a complete and innovative solution for college students to explore career options. [ABSTRACT FROM AUTHOR]

The A2N process with BAF as a nitrification unit was researched aiming at the low carbon and nitrogen ratio domestic wastewater in southern China. According to the problems that effluent ammonia exceeded the standard because of the ammonia carried in surpass sludge and total phosphate couldn't reach the discharge standard when SS of secondary settling tank was high, a secondary BAF was set up, and the total treatment effect of A2N/BAF process was studied. Results showed that the average removal rates of COD, ammonia and TP of A2N stage were 82.0%, 70.9% and 90.0% , respectively. Effluent ammonia concentration of secondary settling tank exceeded 10 mg/L when influent was more than 40 mg/L. Average concentration of COD, TP, ammonia, nitrate and SS in final effluent were 35, 0. 35, 1.06, 8.01 and 7 mg/L, respectively, which had satisfied the A-level of the national standards. [ABSTRACT FROM AUTHOR]

According to the disadvantages of wastewater two-phase anaerobic treatment process as low start-up speed of ethanol-type fermentation with acidogenic reactor and sludge easily to be washed out, the ethanol-type fermentation formation of acidogenic reactor was studied by seeding anaerobic granular sludge, controlling volume loading rate, loading increased range, alkalinity, etc. The running condition of the reactor was monitored by parameters such as terminal liquid products, pH, ORP and acidifying degree etc. Test showed that the succession process from mixed acid fermentation to butyrate-type fermentation reactor to ethanol-type fermentation of reactor was completed within 34 d. At the end of start-up, the mass concentration of ethanol and acetic acid was 75.9 percent of liquid terminal products ; pH value was 4. 1 - 4. 3 ; ORP value was - 230 - - 250 mV. The sludge properties of seed anaerobic granular sludge changed obviously. Its apparent color changed from black and grey black to khaki and snuff color. The particle size of seed granular sludge became smaller with the range of 0.50 - 1.25 mm. [ABSTRACT FROM AUTHOR]

A process coupled completely autotrophic nitrogen removal over nitrite (CANON)with denitrifying phosphorus removal in a modified anaerobic baffled reactor (ABR) coupled with a membrane bioreactor (MBR), inoculated with ordinary activated sludge, was proposed for treating artificial wastewater with ammonia 200 mg·L -1 and COD/TN=1. This experiment studied the start-up of the process and its nitrogen and phosphorus removal efficiency by controlling the recycle ratio and increasing it from 50% to 200% step by step, with a temperature of (25±1)℃ and pH of 7.5±0.2. The results showed that the anaerobic part in the ABR consumed 70% COD, and resulted in a quick start-up of partial-nitrification at 21 d under low DO and high ammonia nitrogen. Then, by controlling the intermittent aeration (exposure stop ratio:2 h:2 h, DO 0.3-0.4 mg·L -1 ), the start-up of the CANON part in the coupling process was successfully achieved at 132 d, such that the concentration of nitrates in the electron acceptor of the ABR anoxic section increased steadily, and finally the coupling process started successfully at 160 d. With stable operation, the TN removal load in the MBR reached 0.22 kg·(m 3 ·d) -1 , and the average removal efficiency of COD, TN, and PO 4 3- -P was 87.0%, 90.4%, and 81.8%, respectively. The batch experiment estimated that the denitrifying phosphate accumulating organisms (DPAOs) using nitrates as electron acceptors in the ABR accounted for 68% of the phosphate accumulating organisms (PAOs). The DPAOs, ammonia-oxidizing bacteria (AOB), and anaerobic ammonium oxidizing bacteria (AnAOB) have been developed in the system and have good simultaneous nitrogen and phosphorus removal efficiency.

An anaerobic sequencing batch reactor(ASBR)was used to treat low-substrate simulated wastewater with NH 4 + -N and NO 2 - -N concentrations of (25.00±0.40) mg·L -1 by adding sodium acetate, and its effects on start-up of anaerobic ammonia oxidation (ANAMMOX) were investigated under the temperature of 30℃. The results showed that ① The start-up of ANAMMOX could be achieved successfully after 74, 94, 106, and 129 days. The nitrogen removal efficiency was optimum when the COD concentration was between 15.00 and 30.00 mg·L -1 , respectively. The COD concentrations were controlled at 5.00, 15.00, 30.00, and 50.00 mg·L -1 by adding sodium acetate, and its effects on start-up of anaerobic ammonia oxidation (ANAMMOX) were investigated under the temperature of 30℃. The results showed that ① The start-up of ANAMMOX could be achieved successfully after 74, 94, 106, and 129 days. The nitrogen removal efficiency was optimum when the COD concentration was between 15.00 and 30.00 mg·L -1 . In the steady phase, the average effluent concentrations of NH 4 + -N were 1.98 and 1.89 mg·L -1 . ② The average contribution of heterotrophic denitrification to nitrogen removal decreased to 4.78%, 9.59%, 10.21%, and 36.50%, respectively, during start-up process. The average contribution of ANAMMOX to nitrogen removal gradually increased to 95.22%, 90.41%, 89.79%, and 63.50%, respectively. ③ The activities of ANAMMOX exceeded denitrification activities at 44, 76, 86, and 114 days, respectively, which finally reached 0.700, 0.690, 0.670, and 0.510 mg·(g·h) 2 - -N were below 0.62 mg·L -1 , and the average effluent concentrations of TN were 2.37 and 2.28 mg·L -1 . ② The average contribution of heterotrophic denitrification to nitrogen removal decreased to 4.78%, 9.59%, 10.21%, and 36.50%, respectively, during start-up process. The average contribution of ANAMMOX to nitrogen removal gradually increased to 95.22%, 90.41%, 89.79%, and 63.50%, respectively. ③ The activities of ANAMMOX exceeded denitrification activities at 44, 76, 86, and 114 days, respectively, which finally reached 0.700, 0.690, 0.670, and 0.510 mg·(g·h) -1 , and the denitrification activities were 0.110, 0.130, 0.240 and 0.410 mg·(g·h) -1 , respectively. Thus, the research results have provided references for the application of ANAMMOX to engineering.

The nitrogen and phosphorus removal characteristics during the start-up and the long-term operational stability of an anaerobic/anoxic (A/A) ABR coupled aerobic MBR system treating low C/N domestic wastewater were investigated. The results showed that the denitrifying phosphorus bacteria (DPBs) were successfully enriched within 46 d by controlling the nitrate recycling ratio (increasing from 150% to 300%), with a temperature of 30℃±2℃, volume loading rate of 0.8 kg·(m 3 ·d) -1 and sludge reflux ratio of 80% in the ABR, sludge retention time (SRT) in the denitrifying phosphorus removal functional area of 25 d, and the dissolved oxygen (DO) of 1-2 mg·L -1 in the MBR. The net phosphorus release and phosphorus uptake of DPBs reached 20.56 mg·L -1 and 27.74 mg·L -1 , respectively. Batch tests demonstrated that about 84.8% of phosphorus-accumulating organisms (PAOs) could use NO 3 -N as an electron acceptor for denitrifying phosphorus removal. After 50 d of stable operation after the successful system start-up, the average removal rates of COD, NH - -N as an electron acceptor for denitrifying phosphorus removal. After 50 d of stable operation after the successful system start-up, the average removal rates of COD, NH 4 + -N, TN, and PO 4 3- -P were 91.8%, 99.0%, 71.5%, and 94.2%, respectively. The results also suggested that 0.83 mg·L -1 NO 3 - -N was consumed per 1 mg·L -1 PO 4 3- -P removed during the denitrifying phosphorus removal, indicating that the simultaneous nitrogen and phosphorus removal was achieved in the ABR-MBR system.

In order to clarify the microbial community characteristics of the shortcut nitrification start-up with different inoculated sludges in the membrane bioreactor (MBR), the MBR was inoculated with nitrification sludge (R1), anaerobic nitrification sludge (R2) and 1:1 mixed inoculated anaerobic nitrification and denitrification sludge (R3). The results showed that the combination of intermittent aeration and shortened hydraulic retention time (HRT) successfully achieved the shortcut nitrification by R1, R2 and R3 reactors after 46 d, 8 d and 30 d respectively, with the R2 reactor exhibiting the shortest start-up period. During stable operations, the average nitrite accumulation rates of R1, R2 and R3 reactors were 92%, 93% and 94% respectively, and the R3 reactor showed a more stable shortcut nitrification. The results of analyses using ACE, Chao, Shannon, and Simpson diversity indices showed that the microbial abundance and diversity levels of R1 and R2 were significantly lower than that of the inoculant during the stable operation period, while the species abundance in the R3 reactor was slightly reduced and the diversity level was slightly changed. The main bacteria in the three reactors were Proteobacteria and Bacteroidetes after the successful start-up of shortcut nitrification, and the relative abundance of Proteobacteria was increased compared with the inoculated sludge. Proteobacteria were the main denitrifying bacteria, with β- Proteobacteria being the dominant bacteria of the shortcut nitrification system in the three reactors, accounting for 59.6%, 63.6% and 69.3% respectively. Through further analysis, the next dominant bacteria in R1, R2 and R3 were all Nitrosomonas , with 12.8%, 20.2% and 19.7% respectively. Compared with the R1 reactor, there was a certain proportion of shortcut nitrification bacteria in the sludge of the R2 and R3 reactors, which was more favorable to the operation of the shortcut nitrification system.

A CANON reactor with fiber carrier was started up by seeding nitrification sludge and ANAMMOX sludge to study the operating characteristics of a fiber carrier. The results showed that total nitrogen removal load rose from 0.09 kg·(m 3 ·d) -1 to 0.9 kg·(m 3 ·d) -1 and remained steady in the 85th day. This indicated that fiber carrier is beneficial to the accumulation of sludge, and the reactor can maintain a higher biomass. The DO in the reactor reached 5 mg·L -1 with the enrichment of microorganisms, biofilm thickening, and the improvement of the reactor's ability. The DO gradient of the biofilm from the outside to the inside was 0.32-0 mg·L -1 , which could be obtained by a microelectrode. It was shown that the permeability of oxygen to the biofilm decreased, and the amount of nitrifying microorganisms decreased with biofilm thickening. The quantitative PCR results showed that the abundance of ANAMMOX was an order of magnitude more than before. The abundance of AOB increased slightly, while the abundance of NOB stayed at a relatively low level.

The start-up and regional characteristics of a pilot scale integrated PN-ANAMMOX reactor was studied. The results show that inoculated nitrosation suspension filler in the anaerobic zone, ANAMMOX sludge, and common anaerobic sludge in the anaerobic zone can start the reactor quickly. The PN-ANAMMOX reactor was successfully started at 74 days. The removal rate of total nitrogen increased from 0.02 kg·(m 3 ·d) -1 to 0.48 kg·(m 3 ·d) -1 . The analysis of the nitrogen conversion characteristics in two regions showed that the AOB had been in a dominant position in the aerobic zone, and the NOB was inhibited by DO and the matrix, NPR a increased from 0.22 kg·(m 3 ·d) -1 to 0.58 kg·(m 3 ·d) -1 , and NAP a could reach 95% with the increase in anaerobic denitrification capacity. The anaerobic zone was a critical region of the integrated PN-ANAMMOX reactor, and NRR ana increased from 0.02 kg·(m 3 ·d) -1 to 4.7 kg·(m 3 ·d) -1 . During the start-up period (temperature decreased from 32℃ to 27℃), the changes first affected the anaerobic zone, NRR ana decreased to 3.7 kg·(m 3 ·d) -1 (about 21%), with little effect on the aerobic zone. The two regions can achieve a large ANAMMOX bacteria enrichment, as, during this time, the aerobic zone also has a certain denitrification capacity, while the anaerobic zone featured enhanced denitrification.

A pilot-scale bio-filter was constructed for the removal of high concentrations of iron (TFe 9.0-12.0 mg·L -1 , Fe(Ⅱ) 6.5-8.0 mg·L -1 ), manganese (1.9-2.1 mg·L -1 ), and ammonia nitrogen (1.4-1.7 mg·L -1 ) simultaneously from low temperature (5-6℃) groundwater in a plant. The results showed that iron was removed at the beginning of the bio-filter start-up, and manganese and ammonia nitrogen were removed on day 72 and day 75, respectively. The start-up period was influenced by the culture temperature and the raw water quality. For higher filtration rates, the removal of manganese was lower. When the filtration rate was more than 1.0 m·h -1 , the maximum removal of manganese was about 3.0 mg·L -1 . Manganese was the limiting factor for the increase of filtration rate, and the maximum filtration rate of the single bio-filter was 4.5 m·h -1 . When the filtration rate was less than 6.0 m·h -1 , the removal of ammonia nitrogen was about 1.5 mg·L -1 , which was not affected by the filtration rate. Dissolved oxygen (DO) deficiency led to failure with the removal of more ammonia nitrogen. The required thickness of the bio-filter required for purification increased as the concentration of manganese and ammonia nitrogen increased when DO was sufficient. The removed iron, manganese, and ammonia nitrogen move to the depth of the filter layer, and there will be "manganese dissolution" when the filtration rate is increased. Iron and ammonia nitrogen in the filter layer can be oxidized and removed simultaneously. Manganese is oxidized and removed after the iron and ammonia nitrogen. The effective oxidation and removal section of manganese, iron, and ammonia nitrogen are obviously graded.

To shorten the start-up time of the CANON granular sludge process and improve the total nitrogen removal rate in the engineering, the start-up method of CANON granular sludge process and the strategy for enhancing the total nitrogen removal rate were studied in an SBR reactor. During the experiment, the temperature was controlled at 30℃±1℃ and the pH was 7-8, the aeration rate and settling time were operated according to the sludge properties and effect of nitrogen removal. The results showed that the transition of the sludge properties from combined floc-granule to granule was realized after 55 d. The total nitrogen removal rate reached 0.32 kg·(m 3 ·d) -1 and remained stable after 117 d, thus the reactor was started up successfully. With constant improvement of the aeration rate, the average NRR was maintained at 1.35 kg·(m 3 ·d) -1 after 77 d and improvement of the process load was achieved. The results showed that there was good correlation between the NRR and DO, therefore, the NRR can be determined by observing the DO and the process can be maintained stably.

To shorten the start-up time of CANON process and guide the sludge dischargement in the practical project, the start-up of CANNON process and influence of different flocs SRT were studied by inoculation ANAMMOX granules of different proportions in two same specifications of SBR reactor. During the experiment, the temperature was controlled at 30℃±1℃ and pH was 7-8. The results showed that it was not good for CANON process rapid start-up when the two reactors were inoculated with 5% and 10% ANAMMOX granules respectively and the initial FA concentration exceeded 44 mg·L -1 . When the two reactors were inoculated with 5% and 10% ANAMMOX granular sludge, the reactors were started-up successfully on Day 46 and Day 35, respectively. When the flocs SRT was maintained at 30 d, 90 d and un-initiative discharge respectively, the average total nitrogen removal rate could reach 0.35 kg·(m 3 ·d) -1 stably. The quantitative PCR results of the three different flocs SRT showed that with increasing flocs SRT, the abundance of AOB was relatively stable, the abundance of ANAMMOX increased slightly, while the abundance of NOB significant increased. Therefore, it is necessary to elutriate flocs from reactor for decreasing the quantity of NOB and long-term stable operation of the CANON process.

Biofilm coming from a reactor in which One-stage Autotrophic Nitrogen Removal Process exists was selected as inoculum in an expanded granular sludge bed reactor. A potential fast start-up procedure was tested in this research. Wastewater with low ammonium concentration between 60-100 mg·L -1 was applied. The results showed that a One-stage Autotrophic Nitrogen Removal Process was successfully established in 83 days under the following conditions: temperature at (30±2)℃ , pH at 7.8-8.2, dissolved oxygen (DO) at 0.2-1.1mg·L -1 and upflow velocity at 2.0-4.0m·h -1 . After the 83-day operation, the removal efficiencies of NH 4 + -N load, the reactor could maintain a stable state of low DO concentration. Nitrification and anaerobic ammonium oxidation became main reactions that maintained efficient and stable nitrogen removal performance. In addition, nitrite-oxidizing bacteria (NOB) were inhibited. In the start-up process, the average particle diameter of granular sludge increased from 174 to 296 μm. Moreover, scanning electron microscopy showed that the surface of granular sludge was smooth, and most microorganisms were bevibacteria and cocci. Finally, a fluorescence in situ hybridization experiment showed that ammonium oxidation bacteria and anaerobic ammonium oxidation bacteria were distributed on the surface and in the inner space of granular sludge, respectively. The research indicated that a stable autotrophic nitrogen removal granular sludge system was quickly established in the sludge bed.4 + -N load, the reactor could maintain a stable state of low DO concentration. Nitrification and anaerobic ammonium oxidation became main reactions that maintained efficient and stable nitrogen removal performance. In addition, nitrite-oxidizing bacteria (NOB) were inhibited. In the start-up process, the average particle diameter of granular sludge increased from 174 to 296 μm. Moreover, scanning electron microscopy showed that the surface of granular sludge was smooth, and most microorganisms were bevibacteria and cocci. Finally, a fluorescence in situ hybridization experiment showed that ammonium oxidation bacteria and anaerobic ammonium oxidation bacteria were distributed on the surface and in the inner space of granular sludge, respectively. The research indicated that a stable autotrophic nitrogen removal granular sludge system was quickly established in the sludge bed.