Online recovery of nisin during fermentation and its effect on nisin production in biofilm reactor

Data sistem informasi online pada PT Bank XYZ merupakan database yang tersimpan pada web/email server bank yang dapat diakses secara online oleh pemakai. Beberapa faktor internal telah menjadi penyebab kerusakan server dan berakibat tidak beroperasinya sistem. Salah satu cara untuk menyelamatkan data dari kehilangan atau kerusakan adalah melalui manajemen backup data yang pelaksanaanya dijalankan secara teratur. Solusi untuk masalah ini adalah penggabungan metode full backup dan incremental backup dalam manajemen backup data, dimana metode ini sangat mudah digunakan serta ekonomis. Langkah berikutnya setelah backup data adalah proses restore yang merupakan proses pengembalian atau recovery data yang sangat penting apabila terjadi kerusakan data. Pada tulisan ini akan dibahas metode backup data dalam upaya penyelamatan data online. Dalam pemilihan metode backup ini sangat tergantung pada keandalan sistem dan kinerja, sehingga proses penyelamatan data dilakukan dengan tepat dan aman Kata Kunci; backup, database, incremental, online, recovery, restore, server

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OPTIMIZATION CONDITIONS AND APPLICATION OF MOVING BED BIOFILM REACTOR FOR MATURE LANDFILL LEACHATE TREATMENT

Environmental Engineering and Management Journal ◽

10.30638/eemj.2016.010 ◽

2016 ◽

Vol 15 (1) ◽

pp. 81-91

Author(s):

Wei Li ◽

Min Liu ◽

Lei Liu ◽

Yao-wen Guo ◽

Yang-shuo Shen

Keyword(s):

Landfill Leachate ◽

Biofilm Reactor ◽

Moving Bed Biofilm Reactor ◽

Leachate Treatment ◽

Moving Bed ◽

Mature Landfill Leachate

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Phosphorus Release Kinetics in Biofilm Reactors

Water Science & Technology ◽

10.2166/wst.1992.0436 ◽

1992 ◽

Vol 26 (3-4) ◽

pp. 567-576 ◽

Cited By ~ 2

Author(s):

F. A. Ruiz-Treviño ◽

S. González-Martínez ◽

C. Doria-Serrano ◽

M. Hernández-Esparza

Keyword(s):

Phosphorus Removal ◽

Release Kinetics ◽

Phosphorus Release ◽

Organic Substrate ◽

Biofilm Reactor ◽

Substrate Uptake ◽

Biofilm Reactors ◽

Initial Substrate ◽

Linear Behaviour ◽

Substrate Concentrations

This paper presents the kinetic analysis, using Generalized Power-Law equations to describe the results of an experimental investigation conducted on a batch submerged biofilm reactor for phosphorus removal under an anaerobic/aerobic cycle. The observed rates and amounts of phosphorus release and organic substrate uptake in the anaerobic phase leads to a kinetic model in which these two variables are dependent on each other with a non-linear behaviour and reach equilibrium values in both cases, at different times and are function of rate constants ratio. The model has a good fit with experimental data except for C uptake at anaerobic contact times longer than four hours, where other kinetics are implied. Kinetic parameters were obtained with different initial substrate concentrations, anaerobic contact cycles, and type of substrates.

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Anaerobic Thermophilic (55°C) Treatment of TMP Whitewater in Reactors Based on Biomass Attachment and Entrapment

Water Science & Technology ◽

10.2166/wst.1999.0696 ◽

1999 ◽

Vol 40 (11-12) ◽

pp. 67-75 ◽

Cited By ~ 5

Author(s):

Sigrun J. Jahren ◽

Jukka A. Rintala ◽

Hallvard Ødegaard

Keyword(s):

Granular Sludge ◽

Biofilm Reactor ◽

Upflow Anaerobic Sludge Blanket ◽

Hybrid Reactor ◽

Anaerobic Sludge ◽

Loading Rates ◽

Anaerobic Reactors ◽

Multi Stage ◽

Degradation Rates ◽

Thermomechanical Pulping

Thermomechanical pulping (TMP) whitewater was treated in thermophilic (55°C) anaerobic laboratory-scale reactors using three different reactor configurations. In all reactors up to 70% COD removals were achieved. The anaerobic hybrid reactor, composed of an upflow anaerobic sludge blanket (UASB) and a filter, gave degradation rates up to 10 kg COD/m3d at loading rates of 15 kg COD/m3d and hydraulic retention time (HRT) of 3.1 hours. The anaerobic multi-stage reactor, consisting of three compartments, each packed with granular sludge and carrier elements, gave degradation rates up to 9 kg COD/m3d at loading rates of 15-16 kg COD/m3d, and HRT down to 2.6 hours. Clogging and short circuiting eventually became a problem in the multi-stage reactor, probably caused by too high packing of the carriers. The anaerobic moving bed biofilm reactor performed similar to the other reactors at loading rates below 1.4 kg COD/m3d, which was the highest loading rate applied. The use of carriers in the anaerobic reactors allowed short HRT with good treatment efficiencies for TMP whitewater.

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Retention and expression of recombinant plasmids in suspended and biofilm-bound bacteria degrading trichloroethene (TCE)

Water Science & Technology ◽

10.2166/wst.1997.0346 ◽

1997 ◽

Vol 36 (10) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

James D. Bryers ◽

Robert R. Sharp

Keyword(s):

Biofilm Reactor ◽

Bacterial Biofilm ◽

Laboratory Evaluation ◽

Recombinant Bacteria ◽

Suitable Host ◽

Term Operation ◽

Open Environment ◽

Recombinant Microorganisms ◽

Extracellular Polymer

Exposure of plasmid recombinant microorganisms to an open environment, either inadvertently or intentionally, requires research into those fundamental processes that govern plasmid retention, transfer and expression. In the open environment, a majority of the microbial activity occurs associated with an interface, within thin biological layers consisting of cells and their insoluble extracellular polymer, layers known as biofilms. Current toxic wastewater or wastegas treatment reactors exploit bacterial biofilm systems for certain system operating advantages. Using recombinant bacteria within a biofilm reactor to degrade xenobiotic wastes requires finding a suitable host to harbor and express the desired plasmid phenotype. Suitable host characteristics include: the ability to produce copious amounts of biofilm, resistance to waste-related injury and toxicity, and the ability to retain and express the desired plasmid during long term operation. This paper reports on a laboratory evaluation of factors governing plasmid retention and the expression of trichloroethene (TCE) degradative capacity in both suspended and biofilm cultures.

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Use of a dynamic gassing-out method for activity and oxygen diffusion coefficient estimation in biofilms

Water Science & Technology ◽

10.2166/wst.1998.0611 ◽

1998 ◽

Vol 37 (4-5) ◽

pp. 171-175

Author(s):

Artem Khlebnikov ◽

Falilou Samb ◽

Paul Péringer

Keyword(s):

Diffusion Coefficient ◽

Oxygen Uptake ◽

Oxygen Diffusion ◽

Fixed Bed ◽

Biofilm Reactor ◽

Strictly Aerobic ◽

Comamonas Testosteroni ◽

Respiration Activity ◽

Oxygen Diffusion Coefficient ◽

Biofilm Development

p-toluenesulphonic acid degradation by Comamonas testosteroni T-2 in multi-species biofilms was studied in a fixed bed biofilm reactor. The polypropylene static mixer elements (Sulzer Chemtech Ltd., Switzerland) were used as a support matrix for biofilm formation. Biofilm respiration was estimated using the dynamic gassing-out oxygen uptake method. A strong relation between oxygen uptake and reactor degradation efficiency was observed, because p-toluenesulphonate degradation is a strictly aerobic process. This technique also allowed us to estimate the thickness of the active layer in the studied system. The mean active thickness was in order of 200 μm, which is close to maximum oxygen penetration depth in biofilms. A transient mathematical model was established to evaluate oxygen diffusitivity in non-steady-state biofilms. Based on the DO concentration profiles, the oxygen diffusion coefficient and the maximum respiration activity were calculated. The oxygen diffusion coefficient obtained (2 10−10-1.2 10−9 m2 s−1) is in good agreement with published values. The DO diffusion coefficient varied with biofilm development. This may be, most likely, due to the biofilm density changes during the experiments. The knowledge of diffusivity changes in biofilms is particularly important for removal capacity estimation and appropriate reactor design.

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