Aeration control on a nitrifying biofilter system by using on-line analyzers

2000 ◽  
Vol 41 (4-5) ◽  
pp. 369-374
Author(s):  
N. Puznava ◽  
D. Thornberg ◽  
P. Magnin ◽  
E. Reddet
Keyword(s):  
Process Control ◽  
Dissolved Oxygen ◽  
Large Scale ◽  
Air Flow ◽  
Ammonia Concentration ◽  
Effluent Quality ◽  
Operation Costs ◽  
New Process ◽  
On Line ◽  
Rainy Days

Two new ways of controlling the aeration in nitrifying biofilters, by measuring on-line dissolved oxygen and ammonia concentration in the effluent of the filter, are compared to the standard control using time tables with constant air flow. Both on pilot and large scale, the new process control concepts proved to be very efficient in optimizing operation costs for aeration (up to 70% during rainy days) and to guarantee a demanded effluent quality.

Simple control strategies of methanol dosing for post-denitrification

1998 ◽  
Vol 38 (3) ◽  
pp. 291-297 ◽  
Author(s):  
N. Puznava ◽  
S. Zeghal ◽  
E. Reddet
Keyword(s):  
Control Strategies ◽  
Operating Cost ◽  
Feed Water ◽  
Effluent Quality ◽  
Second Stage ◽  
Point Tracking ◽  
Regulatory Constraints ◽  
Operation Costs ◽  
Line Measurement ◽  
On Line

The objective of this work is to propose a simple but efficient way of controlling the carbon addition for the post-denitrification process in order to comply with regulatory constraints and optimize operating cost. A Biostyr® pilot column filled with polystyrene beads was used for the experiments. In order to simulate a secondary treated water from a nitrifying stage with a carbon source addition, the feed water was composed of river water dosed with nitrates, phosphates and methanol. Methanol was added initially with no control (at different constant rates) and in a second stage with different control strategies based on the on-line measurement of inlet and/or outlet nitrate concentrations. This simple dosing mode proved to be very efficient in set-point tracking to ensure the effluent quality and in minimizing the methanol addition (up to 20% less methanol consumption), thus optimizing operation costs.

Nitrogen removal in a SBR using the OGAR process control system

2002 ◽  
Vol 46 (4-5) ◽  
pp. 125-130 ◽  
Author(s):  
Z. Tomlins ◽  
M. Thomas ◽  
J. Keller ◽  
J.-M. Audic ◽  
V. Urbain
Keyword(s):  
Control System ◽  
Process Control ◽  
Total Nitrogen ◽  
Environmental Protection Agency ◽  
Batch Reactor ◽  
Industrial Process ◽  
Ammonia Concentration ◽  
Process Control System ◽  
Treated Effluent ◽  
On Line

OGAR® is an industrial process control system that utilises on-line redox measurements to control the aeration sequence in an activated sludge process. Compared to conventional process control systems that use dissolved oxygen, OGAR® makes use of redox as a control parameter during both aerobic and anoxic conditions. This paper reports on its first application in a sequencing batch reactor. The principal aim of this project is to demonstrate the capability of OGAR® to achieve concentrations of total nitrogen in the treated effluent of less than 10 mg/L, which are typically stipulated by Queensland's Environmental Protection Agency (EPA). In this study the use of the control system resulted in the following SBR performance: consistent effluent total nitrogen less than 5.0 mg/L; ammonia concentration reduced from 31.6 mg/L to 0.32 mg/L, effluent nitrate 2.8 mg/L; DO setpoint 1.5 mg/L had 10% higher effluent total nitrogen compared to DO setpoint 4.0 mg/L and redox end-points for nitrification 400 mV, denitrification 150 mV.

Automatic buffer capacity based sensor for effluent quality monitoring

1996 ◽  
Vol 33 (1) ◽  
pp. 81-87
Author(s):  
L. Van Vooren ◽  
P. Willems ◽  
J. P. Ottoy ◽  
G. C. Vansteenkiste ◽  
W. Verstraete
Keyword(s):  
Wastewater Treatment ◽  
Buffer Capacity ◽  
Wastewater Treatment Plants ◽  
Data Interpretation ◽  
Full Scale ◽  
Quality Monitoring ◽  
Effluent Quality ◽  
Capacity Curves ◽  
On Line

The use of an automatic on-line titration unit for monitoring the effluent quality of wastewater plants is presented. Buffer capacity curves of different effluent types were studied and validation results are presented for both domestic and industrial full-scale wastewater treatment plants. Ammonium and ortho-phosphate monitoring of the effluent were established by using a simple titration device, connected to a data-interpretation unit. The use of this sensor as the activator of an effluent quality proportional sampler is discussed.

Upgrading effluent quality for lagoon-based systems

1995 ◽  
Vol 31 (12) ◽  
pp. 379-387 ◽  
Author(s):  
Henryk Melcer ◽  
Brian Evans ◽  
Stephen G. Nutt ◽  
Anthony Ho
Keyword(s):  
Urban Communities ◽  
Ammonia Concentration ◽  
Sand Filters ◽  
Plant Operation ◽  
Capital Costs ◽  
Effluent Quality ◽  
Waste Sludge ◽  
Best Available Technology ◽  
Available Technology ◽  
Aeration Plant

To establish Best Available Technology Economically Achievable (BATEA) in non-urban communities which presently use conventional lagoon technology, an investigation was undertaken to evaluate alternatives which can be used to improve lagoon effluent and establish costs. Evaluated were the “Sutton” and the intermittent sand filtration or “New Hamburg” processes. The Sutton concept consists of a nitrifying extended-aeration plant followed by polishing lagoons, with waste sludge discharged into the lagoons. The New Hamburg concept consists of aerated or facultative lagoons, with the lagoon effluent sprayed intermittently over sand filters. The Sutton plants produce an improved effluent quality relative to conventional facultative lagoons in terms of BOD5 and TSS concentrations. Increases in ammonia concentration across the polishing pond occur after 5-7 years of plant operation, suggesting a need to implement a regular program of sludge removal from the lagoon. The New Hamburg process results in a significant improvement in effluent quality in terms of BOD5, TSS, TP, TKN, NH3-N and H2S concentrations. Approximate capital costs for upgrading the existing conventional lagoons in Ontario to Sutton and New Hamburg process facilities are estimated at US $221 million and US $93 million, respectively.

A Drug Target Interaction Prediction Based on LINE-RF Learning

2020 ◽  
Vol 15 (7) ◽  
pp. 750-757
Author(s):  
Jihong Wang ◽  
Yue Shi ◽  
Xiaodan Wang ◽  
Huiyou Chang
Keyword(s):  
Network Topology ◽  
Drug Target ◽  
Large Scale ◽  
Representation Learning ◽  
New Drugs ◽  
Combination Method ◽  
Learning Methods ◽  
Network Representation ◽  
On Line ◽  
Clinical Experiments

Background: At present, using computer methods to predict drug-target interactions (DTIs) is a very important step in the discovery of new drugs and drug relocation processes. The potential DTIs identified by machine learning methods can provide guidance in biochemical or clinical experiments. Objective: The goal of this article is to combine the latest network representation learning methods for drug-target prediction research, improve model prediction capabilities, and promote new drug development. Methods: We use large-scale information network embedding (LINE) method to extract network topology features of drugs, targets, diseases, etc., integrate features obtained from heterogeneous networks, construct binary classification samples, and use random forest (RF) method to predict DTIs. Results: The experiments in this paper compare the common classifiers of RF, LR, and SVM, as well as the typical network representation learning methods of LINE, Node2Vec, and DeepWalk. It can be seen that the combined method LINE-RF achieves the best results, reaching an AUC of 0.9349 and an AUPR of 0.9016. Conclusion: The learning method based on LINE network can effectively learn drugs, targets, diseases and other hidden features from the network topology. The combination of features learned through multiple networks can enhance the expression ability. RF is an effective method of supervised learning. Therefore, the Line-RF combination method is a widely applicable method.

scholarly journals Glucose-Limited Fed-Batch Cultivation Strategy to Mimic Large-Scale Effects in Escherichia coli Linked to Accumulation of Non-Canonical Branched-Chain Amino Acids by Combination of Pyruvate Pulses and Dissolved Oxygen Limitation

2021 ◽  
Vol 9 (6) ◽  
pp. 1110
Author(s):  
Ángel Córcoles García ◽  
Peter Hauptmann ◽  
Peter Neubauer
Keyword(s):  
Amino Acids ◽  
Dissolved Oxygen ◽  
Large Scale ◽  
Scale Effects ◽  
Branched Chain Amino Acids ◽  
Oxygen Limitation ◽  
Fed Batch ◽  
Fermentation Products ◽  
Cultivation Strategy ◽  
Branched Chain

Insufficient mixing in large-scale bioreactors provokes gradient zones of substrate, dissolved oxygen (DO), pH, and other parameters. E. coli responds to a high glucose, low oxygen feeding zone with the accumulation of mixed acid fermentation products, especially formate, but also with the synthesis of non-canonical amino acids, such as norvaline, norleucine and β-methylnorleucine. These amino acids can be mis-incorporated into recombinant products, which causes a problem for pharmaceutical production whose solution is not trivial. While these effects can also be observed in scale down bioreactor systems, these are challenging to operate. Especially the high-throughput screening of clone libraries is not easy, as fed-batch cultivations would need to be controlled via repeated glucose pulses with simultaneous oxygen limitation, as has been demonstrated in well controlled robotic systems. Here we show that not only glucose pulses in combination with oxygen limitation can provoke the synthesis of these non-canonical branched-chain amino acids (ncBCAA), but also that pyruvate pulses produce the same effect. Therefore, we combined the enzyme-based glucose delivery method Enbase® in a PALL24 mini-bioreactor system and combined repeated pyruvate pulses with simultaneous reduction of the aeration rate. These cultivation conditions produced an increase in the non-canonical branched chain amino acids norvaline and norleucine in both the intracellular soluble protein and inclusion body fractions with mini-proinsulin as an example product, and this effect was verified in a 15 L stirred tank bioreactor (STR). To our opinion this cultivation strategy is easy to apply for the screening of strain libraries under standard laboratory conditions if no complex robotic and well controlled parallel cultivation devices are available.

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