Removal of nitrogen from secondary effluent of a petrochemical industrial park by a hybrid biofilm-carrier reactor with one-stage ANAMMOX

2014 ◽  
Vol 69 (12) ◽  
pp. 2526-2532 ◽  
Author(s):  
Han-Lin Lin ◽  
Hsiang-Wei Tsao ◽  
Yu-Wen Huang ◽  
Yi-Chuan Wang ◽  
Keng-Hao Yang ◽  
...  
Keyword(s):  
Continuous Flow ◽  
Removal Rate ◽  
Operating Conditions ◽  
Carbon Substrate ◽  
Industrial Park ◽  
Secondary Effluent ◽  
Petrochemical Wastewater ◽  
One Stage ◽  
Biofilm Carrier ◽  
16S Rrna Clone Library

A laboratory study was undertaken to explore the capability of one-stage ANAMMOX in a hybrid biofilm-carrier reactor (HBCR) fed with petrochemical wastewater. Under favorable operating conditions in continuous-flow operations (at the dissolved oxygen level of 0.5–1.0 mg L−1), the average total nitrogen (TN) removal efficiency reached 62–67% and approximately 90% of TN can be removed by ANAMMOX. In batch operations of the hybrid biofilm-carrier reactor (without adding carbon substrate), the specific TN removal rate of the reactor in which both Kaldnes and nonwoven carriers were kept was two-fold higher than that of the reactor in which only nonwoven carriers were kept. This indicated that the microbial activity of thinner biofilms (Kaldnes carriers) was remarkably higher than that of thicker biofilms (nonwoven carriers). Finally, based on the 16S rRNA clone library, a cluster of ANAMMOX Candidatus Kuenenia stuttgartiensis was identified.

Nitrification studies on fertilizer wastewaters in activated sludge and biofilm reactors

1995 ◽  
Vol 32 (12) ◽  
pp. 141-148 ◽  
Author(s):  
Ferhan Çeçen ◽  
Elvan Orak ◽  
Pinar Gökçin
Keyword(s):  
Dissolved Oxygen ◽  
Activated Sludge ◽  
Continuous Flow ◽  
Removal Rate ◽  
Ammonia Concentration ◽  
Biofilm Reactor ◽  
Operating Conditions ◽  
Nitrite Accumulation ◽  
Operational Conditions ◽  
Oxygen Concentrations

Nitrification characteristics of a high-strength fertilizer wastewater were studied in a batch activated sludge and a continuous-flow biofilm reactor. In a batch activated sludge system one of the most decisive factors was the pH control. The results in terms of ammonium decrease and nitrite build-up were fitted to kinetic models and it was shown that in the absence of inhibitory factors like high free ammonia or nitrous acid build-up the behaviour was similar to that in the case of low-strength wastes. Continuous-flow studies in the biofilm reactor at different loading rates and dissolved oxygen concentrations indicated that such a biofilm reactor could be employed in the treatment of highly nitrogenous fertilizer wastes. Depending on operating conditions such as dissolved oxygen concentration and loading rate an effluent ammonia concentration as low as 4 mg NH4−N/L could be achieved. In the dissolved oxygen ranges of 3.2 mg/L–3.5 mg/L the system reached the maximum removal rate of 0.17 kg NH4−N/m3.d. When the dissolved oxygen was increased to 4.9 mg/L, removal rates as high as 0.41 kg NH4−N/m3.d could be obtained. Also in continuous-flow operation nitrite accumulation reached in some cases a considerable degree depending on the bulk nitrogen and dissolved oxygen concentrations. The nitrite accumulation in the effluent stream varied from 4–180 mg NO2−N/L depending on operational conditions.

Determination of cost-efficient cooling power range for improving the performance of internally cooled ultrasonic atomization liquid desiccant dehumidifiers

2020 ◽  
Vol 29 (9) ◽  
pp. 1260-1276
Author(s):  
Zili Yang ◽  
Lu-An Chen ◽  
Ruiyang Tao ◽  
Ke Zhong
Keyword(s):  
Power Efficiency ◽  
Removal Rate ◽  
Operating Conditions ◽  
Cooling Power ◽  
Internal Cooling ◽  
Liquid Desiccant ◽  
Improvement Rate ◽  
Ultrasonic Atomization ◽  
Internally Cooled ◽  
Cost Efficient

Liquid desiccant dehumidifiers (LDDs) can be improved by adding internal cooling. However, the addition of excessive cooling power may deteriorate the system‘s cost-efficiency, whereas the addition of insufficient cooling power leads to negligible performance improvements. The objective of this study is to determine the suitable cost-efficient cooling power range for improving the performance of internally cooled LDDs (IC-LDDs). A novel method and a set of criteria related to the moisture removal rate, cooling-power efficiency ( ηc) and coefficient of dehumidification performance from cooling power ( DCOPcooling) were proposed to determine cost-efficient cooling power. The internally cooled ultrasonic atomization liquid desiccant system (IC-UADS), together with a well-validated model based on the conservation laws of mass and energy and the sensible heat balance, was adopted to demonstrate the analysis. The results showed that, although the dehumidification performance improves with increasing cooling power, the improvement rate decreases, while ηcand DCOPcoolingdecline quickly (by 87.9%). For cost-efficient improvement, the necessary power proportion of internal cooling to the system‘s target dehumidification capacity tends to be stable, which was about 29% for the IC-UADS, and independent of the operating conditions. The results may help to determine the reasonable cooling power range for cost-efficient improvement of IC-LDDs.

Study on De-Nitrification of Improved Step-Feed Progress

2014 ◽  
Vol 703 ◽  
pp. 171-174
Author(s):  
Bing Wang ◽  
Yi Xiao ◽  
Shou Hui Tong ◽  
Lan Fang ◽  
Da Hai You ◽  
...  
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Nitrogen Removal ◽  
Removal Rate ◽  
Operating Conditions ◽  
Removal Mechanism ◽  
Aerobic Zone

Improved step-feed de-nitrification progress combined with biological fluidized bed was introduced in this study. The progress had good performance and capacity of de-nitrification and organic matter. The experiment result showed that the de-nitrification efficiency of the improved biological fluidized bed with step-feed process was higher than the fluidized bed A/O process under the same water quality and the operating conditions. When the influent proportion of each segment was equal, the system showed good nitrogen removal efficiency with the change of influent C/N ratio, HRT and sludge return ratio. The removal rate of TN reached up to 88.2%. It showed that the simultaneous nitrification and de-nitrification phenomenon happened in the aerobic zone. The nitrogen removal mechanism was also studied.

Lab Scale Study on Synergistic Disinfection of WWTPS Secondary Effluent by Ultrasonic and Ozone

2012 ◽  
Vol 433-440 ◽  
pp. 4751-4756 ◽  
Author(s):  
Hao Wu ◽  
Zi Fu Li ◽  
Xin Jin ◽  
Xin Zhao ◽  
Fu Rong Deng
Keyword(s):  
Reaction Time ◽  
Removal Rate ◽  
Research Direction ◽  
Synergistic Action ◽  
Color Removal ◽  
Secondary Effluent ◽  
Disinfection Methods ◽  
Number Of Microorganisms ◽  
New Research ◽  
Ozone Disinfection

Secondary effluent from WWTPS still contains a large number of microorganisms, therefore, disinfection is essential. There are many disadvantages in using traditional disinfection methods, so the combination of disinfection techniques is a new research direction. Ozone combined with ultrasound is one of them. In this experiment, the inactivation of the total coli forms, color removal and UV254 removal of secondary effluent by a combination of ultrasonic (frequency20 kHz; power100W) and ozone disinfection was investigated. The results show that the effect of the synergistic action of 30s US and ozone disinfection is superior to the effect of individual ozone disinfection. After 15min synergistic disinfection, the total coli forms inactivation rate is up to 99.9%, simultaneously color removal rate to 80% and UV254 removal rate to 52%. Compared with individual ozone disinfection, reaction time was reduced by 5 min.

A new strategy to improve ramie degumming based on removal of the xylan branched structure

2021 ◽  
pp. 004051752110449
Author(s):  
Huihui Wang ◽  
Tong Shu ◽  
Pandeng Li ◽  
Yun Bai ◽  
Mengxiong Xiang ◽  
...  
Keyword(s):  
Removal Rate ◽  
Natural Fibers ◽  
Green Manufacturing ◽  
Operating Conditions ◽  
Ramie Fiber ◽  
Wild Type ◽  
Acetyl Xylan Esterase ◽  
Degumming Process ◽  
Main Component ◽  
Engineered Strain

Ramie fiber is known as the “king of natural fibers,” and the key to its wide application is efficient and green manufacturing. Microbial degumming has gradually become a hot area of research due to its environmental protection and mild operating conditions. However, some gummy materials remain after microbial degumming. Xylan is the main component of residual gums; its acetylated branched chains create the space barrier that makes the removal of hemicellulose difficult during ramie degumming. An acetyl xylan esterase (AXE) was obtained from Bacillus pumilus and characterized to solve this problem. Its optimum temperature and pH were 35°C and 8.0, respectively, and it had good temperature and pH stability. These properties were consistent with the conditions of ramie degumming and they laid a foundation for the application of AXE in ramie degumming. Besides, an engineered strain with a high activity of AXE was constructed successfully on the basis of the wild-type degumming strain Pectobacterium carotovorum HG-49 and used for ramie degumming. The removal rate of hemicellulose and total gums by the engineered strain increased by 4.89% and 2.53%, respectively, compared with that of the wild-type strain. Moreover, the role of this AXE in ramie degumming was further proven by X-ray diffraction and scanning electron microscopy. This study showed that AXE played an important role in the removal of hemicellulose in the degumming process of ramie fibers, thus providing a promising degumming strategy for ramie and other bast fiber plants.

Turbocharger Radial Turbine Response to Pulse Amplitude

2021 ◽  
Author(s):  
Roberto Mosca ◽  
Shyang Maw Lim ◽  
Mihai Mihaescu
Keyword(s):  
Heat Transfer ◽  
Continuous Flow ◽  
Viscous Friction ◽  
Pulse Amplitude ◽  
Operating Conditions ◽  
System Response ◽  
Maximum Speed ◽  
Detached Eddy Simulation ◽  
Beneficial Effects ◽  
Eddy Simulation

Abstract Under on-engine operating conditions, a turbocharger turbine is subject to a pulsating flow and, consequently, experiences deviations from the performance measured under continuous flow. Furthermore, due to the high exhaust gas temperatures, heat transfer further deteriorates the turbine performance. The complex interaction of the aerothermodynamic mechanisms occurring inside the hot-side, and consequently the turbine behavior, is largely affected by the shape of the pulse, which can be parameterized through three parameters: pulse amplitude, frequency, and temporal gradient. This paper investigates the hot-side system response to the pulse amplitude via a Detached Eddy Simulation (DES) approach of a radial turbocharger turbine system including exhaust manifold. Firstly, the computational model is validated against experimental data obtained under gas stand continuous flow conditions. Then, two different mass flow pulses, characterized by a pulse amplitude difference of ≈ 5%, are compared. An exergy-based post-processing approach shows the beneficial effects of increasing pulse amplitude. An improvement of the turbine power by 1.3%, despite the increment of the heat transfer and total internal irreversibilities by 5.8% and 3.4%, respectively, is reported. As a result of the higher maximum speed, internal losses by viscous friction are responsible for the growth of the total internal irreversibilities as pulse amplitude increases.

Granular biomass capable of partial nitritation and anammox

2008 ◽  
Vol 58 (5) ◽  
pp. 1113-1120 ◽  
Author(s):  
S. E. Vlaeminck ◽  
L. F. F. Cloetens ◽  
M. Carballa ◽  
N. Boon ◽  
W. Verstraete
Keyword(s):  
Removal Rate ◽  
Batch Reactor ◽  
Ammonium Oxidation ◽  
Autotrophic Nitrification ◽  
Partial Nitritation ◽  
One Stage ◽  
Biomass Retention ◽  
Granular Biomass ◽  
The One

A novel and efficient way of removing nitrogen from wastewater poor in biodegradable organic carbon, is the combination of partial nitritation and anoxic ammonium oxidation (anammox), as in the one-stage oxygen-limited autotrophic nitrification/denitrification (OLAND) process. Since anoxic ammonium-oxidizing bacteria grow very slowly, maximum biomass retention in the reactor is required. In this study, a lab-scale sequencing batch reactor (SBR) was used to develop granular, rapidly settling biomass. With SBR cycles of one hour and a minimum biomass settling velocity of 0.7 m/h, OLAND granules were formed in 1.5 months and the nitrogen removal rate increased from 50 to 450 mg N L−1 d−1 in 2 months. The granules had a mean diameter of 1.8 mm and their aerobic and anoxic ammonium-oxidizing activities were well equilibrated to perform the OLAND reaction. Fluorescent in-situ hybridization (FISH) demonstrated the presence of both β-proteobacterial aerobic ammonium oxidizers and planctomycetes (among which anoxic ammonium oxidizers) in the granules. The presented results show the applicability of rapidly settling granular biomass for one-stage partial nitritation and anammox.

scholarly journals Investigation of the Coal Gasification Process Under Various Operating Conditions Inside a Two-Stage Entrained Flow Gasifier

2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Armin Silaen ◽  
Ting Wang
Keyword(s):  
Coal Gasification ◽  
Operating Conditions ◽  
Coal Slurry ◽  
Two Stage ◽  
Heating Value ◽  
Fuel Distribution ◽  
Entrained Flow ◽  
One Stage ◽  
Gasification Process ◽  
Entrained Flow Gasifier

Numerical simulations of the coal gasification process inside a generic 2-stage entrained-flow gasifier fed with Indonesian coal at approximately 2000 metric ton/day are carried out. The 3D Navier–Stokes equations and eight species transport equations are solved with three heterogeneous global reactions, three homogeneous reactions, and two-step thermal cracking equation of volatiles. The chemical percolation devolatilization (CPD) model is used for the devolatilization process. This study is conducted to investigate the effects of different operation parameters on the gasification process including coal mixture (dry versus slurry), oxidant (oxygen-blown versus air-blown), and different coal distribution between two stages. In the two-stage coal-slurry feed operation, the dominant reactions are intense char combustion in the first stage and enhanced gasification reactions in the second stage. The gas temperature in the first stage for the dry-fed case is about 800 K higher than the slurry-fed case. This calls for attention of additional refractory maintenance in the dry-fed case. One-stage operation yields higher H2, CO and CH4 combined than if a two-stage operation is used, but with a lower syngas heating value. The higher heating value (HHV) of syngas for the one-stage operation is 7.68 MJ/kg, compared with 8.24 MJ/kg for two-stage operation with 75%–25% fuel distribution and 9.03 MJ/kg for two-stage operation with 50%–50% fuel distribution. Carbon conversion efficiency of the air-blown case is 77.3%, which is much lower than that of the oxygen-blown case (99.4%). The syngas heating value for the air-blown case is 4.40 MJ/kg, which is almost half of the heating value of the oxygen-blown case (8.24 MJ/kg).

scholarly journals Investigation of the Efficiency of Phosphorus Removal Using Anionic Resins From the Continuous Flow in the Waste Stabilization Pond Outlet: A Case Study of Kaboodrahang Wastewater Treatment Plant

2019 ◽  
Vol 6 (1) ◽  
pp. 16-20
Author(s):  
Ali Akbar Rahmani Sarmazdeh ◽  
Mostafa Leili
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Phosphorus Removal ◽  
Continuous Flow ◽  
Removal Rate ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Cold Season ◽  
Stabilization Pond ◽  
The Mean

This research mainly aimed to investigate phosphorus removal from stabilization pond effluent by using anionic resins in the continuous flow mode of operation due to high amounts of phosphorus in the wastewater treatment plant effluent of Kaboodrahang, western Iran, as well as the violation from a prescribed effluent standard to discharge receiving the surface waters. For this purpose, the pilot was made of a plexiglass cylinder and other equipment such as pump and other accessories, as well as Purolite A-100 resin. The reactor effects on the desired study parameters were assessed in two warm and cold seasons. The results showed that the phosphorus concentrations reduced from 7-10 mg/L to 4-7 mg/L and the rate of phosphorus removal was higher in the hot season compared to the cold season. Moreover, the optimum temperature and pH were obtained 21ºC and 8.5, respectively. The mean inlet biological oxygen demand (BOD) was 150 mg/L for both warm and cold seasons, where the highest removal rate of 17% was obtained in the cold season. The mean chemical oxygen demand concentration of the pilot was 250 mg/L for both seasons, and the highest removal rate was observed in the cold season with an efficiency of 18%. Regarding the total suspended solids with the mean inlet of 230 mg/L, the highest removal efficiency was obtained 6% in the warm season.

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