High Rate Transient Start-Up Flow with Glass Fibres Filled Thermoplastics

Aerobic upflow sludge blanket(AUSB) process is a new biological wastewater treatment method applying the concept of the self-immobilization to activated sludge. Two sets of AUSB system with different mixing velocities of 3 rpm(R1) and 6 rpm(R2) were operated for high-rate treatment of synthetic wastewater. The COD removal efficiency in R2 was higher than R1 at the same loading rate up to 7 kg/m3·day. However, in R1, the sludge bulking was observed at the end of the experiment. The chocolate colored granules were formed about 5 days after the start-up. The morphological study on the granular sludge consortia was made with both scanning electron and optical microscopes. The granules were 0.5-2.5 mm in diameter and mainly consisted of bacteria with pili-like appendages and filamentous bacteria, which were thought to be Sphaerotilus natans and Beggiatoa. In R1, the long multicellular filaments causing bulking were prevalent in the granule, while in R2 overgrowth of filamentous bacteria was prevented with appropriate shear stress resulting in higher MLSS density. Experimental results indicated that granulation could be controlled by physical stress on granular sludge.

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Stable and high-rate anaerobic co-digestion of food waste and cow manure: Optimisation of start-up conditions

Bioresource Technology ◽

10.1016/j.biortech.2020.123195 ◽

2020 ◽

Vol 307 ◽

pp. 123195 ◽

Cited By ~ 4

Author(s):

Bao-Shan Xing ◽

Sifan Cao ◽

Yule Han ◽

Junwei Wen ◽

Kaidi Zhang ◽

...

Keyword(s):

Food Waste ◽

High Rate ◽

Cow Manure ◽

Start Up

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Biomass Retention in Advanced Anaerobic Reactors

Water Science & Technology ◽

10.2166/wst.1990.0132 ◽

1990 ◽

Vol 22 (1-2) ◽

pp. 17-24 ◽

Cited By ~ 6

Author(s):

G. Albagnac

Keyword(s):

Current Knowledge ◽

Point Of View ◽

High Rate ◽

Efficient Treatment ◽

Anaerobic Reactors ◽

Start Up ◽

Biomass Retention ◽

Rate Processes ◽

Bacterial Aggregates ◽

Bacterial Concentrations

Recognition of the advantages of anaerobic wastewater treatment induced the development of high rate processes, i.e. reactors designed to allow an efficient treatment of even diluted streams. The performance of these advanced reactors is mainly dependent on the retention within the reactor of high bacterial concentrations. The prevailing mechanism is either the formation of bacterial aggregates with good settling characteristics, the development of methanogenic biolayers at the surface of inert carriers or both. During the past decade information on the biology of methanogenic ecosystems became available at an increasing rate. From a practical point of view it can be stated that the biological conversion of organic compounds to methane is reasonably well understood. However the current knowledge on the aggregation and adhesion of methanogenic consortia remains very limited. In most cases reactor start-up procedures are rather long and appear to be more empirical than rational. This paper is a brief presentation on the current knowledge of methanogenic aggregates and biofilms. The fundamental aspects of bacterial adhesion and the modelling of anaerobic biofilms growth are presented elsewhere.

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Rapid start-up of a nitrifying reactor using aerobic granular sludge as seed sludge

Water Science & Technology ◽

10.2166/wst.2012.888 ◽

2012 ◽

Vol 65 (3) ◽

pp. 581-588 ◽

Cited By ~ 8

Author(s):

Naohiro Kishida ◽

Goro Saeki ◽

Satoshi Tsuneda ◽

Ryuichi Sudo

Keyword(s):

Removal Rate ◽

Granular Sludge ◽

Ammonia Removal ◽

High Rate ◽

Aerobic Granular Sludge ◽

Nitrite Accumulation ◽

Ammonia Oxidizing Bacteria ◽

Continuous Stirred Tank Reactor ◽

Start Up ◽

Seed Sludge

In this study, the effectiveness of aerobic granular sludge as seed sludge for rapid start-up of nitrifying processes was investigated using a laboratory-scale continuous stirred-tank reactor (CSTR) fed with completely inorganic wastewater which contained a high concentration of ammonia. Even when a large amount of granular biomass was inoculated in the reactor, and the characteristics of influent wastewater were abruptly changed, excess biomass washout was not observed, and biomass concentration was kept high at the start-up period due to high settling ability of the aerobic granular sludge. As a result, an ammonia removal rate immediately increased and reached more than 1.0 kg N/m3/d within 20 days and up to 1.8 kg N/m3/d on day 39. Subsequently, high rate nitritation was stably attained during 100 days. However, nitrite accumulation had been observed for 140 days before attaining complete nitrification to nitrate. Fluorescence in situ hybridization analysis revealed the increase in amount of ammonia-oxidizing bacteria which existed in the outer edge of the granular sludge during the start-up period. This microbial ecological change would make it possible to attain high rate ammonia removal.

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An operational protocol for facilitating start-up of single-stage autotrophic nitrogen-removing reactors based on process stoichiometry

Water Science & Technology ◽

10.2166/wst.2013.157 ◽

2013 ◽

Vol 68 (3) ◽

pp. 514-521 ◽

Cited By ~ 12

Author(s):

A. G. Mutlu ◽

A. K. Vangsgaard ◽

G. Sin ◽

B. F. Smets

Keyword(s):

Single Stage ◽

High Rate ◽

Normal Operation ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Trial And Error ◽

Reactor Operation ◽

N Removal ◽

Start Up ◽

Decision Making Tool

Start-up and operation of single-stage nitritation–anammox sequencing batch reactors (SBRs) for completely autotrophic nitrogen removal can be challenging and far from trivial. In this study, a step-wise procedure is developed based on stoichiometric analysis of the process performance from nitrogen species measurements to systematically guide start-up and normal operation efforts (instead of trial and error). The procedure is successfully applied to laboratory-scale SBRs for start-up and maintained operation over an 8-month period. This analysis can serve as a strong decision-making tool to take appropriate actions with respect to reactor operation to accelerate start-up or ensure high-rate N removal via the nitritation–anammox pathway.

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Continuous High Rate Anaerobic Treatment of Oleic Acid Based Wastewater is Possible after a Step Feeding Start-Up

Environmental Science & Technology ◽

10.1021/es8031264 ◽

2009 ◽

Vol 43 (8) ◽

pp. 2931-2936 ◽

Cited By ~ 45

Author(s):

Ana J. Cavaleiro ◽

Andreia F. Salvador ◽

Joana I. Alves ◽

Madalena Alves

Keyword(s):

Oleic Acid ◽

Anaerobic Treatment ◽

High Rate ◽

Start Up

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Start-Up, Operation, Monitoring and Control of High-Rate Anaerobic Treatment Systems

Water Science & Technology ◽

10.2166/wst.1991.0226 ◽

1991 ◽

Vol 24 (8) ◽

pp. 207-255 ◽

Cited By ~ 116

Author(s):

R. F. Hickey ◽

W.-M. Wu ◽

M. C. Veiga ◽

R. Jones

Keyword(s):

Operating Experience ◽

Anaerobic Treatment ◽

High Rate ◽

Upflow Anaerobic Sludge Blanket ◽

Laboratory Research ◽

Anaerobic Sludge ◽

Monitoring And Control ◽

Start Up ◽

Process Monitoring And Control ◽

And Control

High-rate anaerobic treatment has emerged as a viable alternative for the treatment of many industrial and municipal wastewaters. A number of different process options have been reduced to practice, although some configurations are clearly more well developed than others. One common thread that links these various processes (principally the Anaerobic Filter, Upflow Anaerobic Sludge Blanket and Expanded/Fluidized Bed Reactors), is the ability to effectively separate solids and hydraulic retention times. This permits design to be based upon the degradative capacity of the anaerobes, not growth rate and results in reduction of treatment times from days (typical for conventional digester systems) to hours. This article compares and contrasts the principles of start-up and operation of these different high-rate anaerobic systems based upon laboratory research and full-scale operating experience gained over the past two decades. The application of anaerobic processes for treatment of certain toxic and hazardous waste streams is just beginning. The limited work performed to date and anticipated future needs for process monitoring and control are also presented in this article.

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A start-up strategy for high-rate partial nitritation based on DO-HRT control

Process Biochemistry ◽

10.1016/j.procbio.2015.11.016 ◽

2016 ◽

Vol 51 (1) ◽

pp. 95-104 ◽

Cited By ~ 11

Author(s):

Lan Wang ◽

Ping Zheng ◽

Ghulam Abbas ◽

Jian Yang ◽

Yajuan Xing ◽

...

Keyword(s):

High Rate ◽

Partial Nitritation ◽

Start Up

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An integrated system for agricultural wastewater treatment

Water Science & Technology ◽

10.2166/wst.1995.0482 ◽

1995 ◽

Vol 32 (12) ◽

pp. 165-171

Author(s):

N. Rovirosa ◽

E. Sánchez ◽

F. Benítez ◽

L. Travieso ◽

A. Pellón

Keyword(s):

Pollutant Removal ◽

Integrated System ◽

High Rate ◽

Low Grade ◽

Adequate Treatment ◽

Agricultural Wastewater ◽

Microalgae Culture ◽

Start Up ◽

Important Amount ◽

Animal Consumption

The treatment of agroindustrial wastewaters gives the possibility of noxious pollutant removal which otherwise would deteriorate the ecosystem even more. The construction and start-up of Integrated Systems for the treatment of such wastes allow the reuse of the treated effluents, with the consequent production of useful by-products. Biological processes for the adequate treatment of 300 m3/day of mixed animal and human wastewaters allow also the production of 1200 m3/day of biogas as an energy supplier and a source of CO2 for microalgae culture in a High Rate Algal Pond. On the other hand, it can be possible to recover the digested sludge as biofertilizer and low grade water useful for crop irrigation. The proposed Integrated System also provides the recovery of 8.3 g/m2/d of algal biomass suitable for animal consumption and the removal of an important amount of noxious pollutants with an average efficiency of 80–98% (COD basis).

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