Nitrogen removal from pharmaceutical manufacturing wastewater via nitrite and the process optimization with on-line control

In this study, laboratory scale experiments were conducted to investigate the nitrogen removal from pharmaceutical manufacturing wastewater. The results indicate that by selective inhibition of free ammonia on oxidizers, nitrogen removal can be achieved by nitritation and denitritation process. The nitrite ratio was above 98% in the aerobic stage and the nitrogen removal efficiency was about 99%. The complete ammonia removal corresponded exactly to the “Ammonia Valley” in the pH versus time graphic and the anoxic reaction was completed when the “Nitrite Knee” appeared in the ORP versus time graphic. Optimization of the SBR cycle by step-feed and on-line control with pH and ORP strategy allowed the carbon and energy saving. The easy operation and the low cost make the SBR system an interesting option for the biological nitrogen removal from the pharmaceutical manufacturing wastewater.

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On-line control of a SBR system for nitrogen removal from industrial wastewater

Water Science & Technology ◽

10.2166/wst.2001.0123 ◽

2001 ◽

Vol 43 (3) ◽

pp. 93-100 ◽

Cited By ~ 44

Author(s):

G. Andreottola ◽

P. Foladori ◽

M. Ragazzi

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Low Cost ◽

Ammonia Removal ◽

High Concentration ◽

Plywood Industry ◽

On Line ◽

Pre Treatment ◽

Study Laboratory ◽

System Operating

In this study, laboratory-scale experiments were conducted applying the SBR activated sludge process to a wastewater from a wood factory operating on plywood production. Due to the fact that the wastewater is characterised with a high concentration of ammonia, the aim was to evaluate the nitrogen removal process with SBR system operating with a on-line control of ORP, pH and DO. The complete ammonia removal corresponded exactly to the “Ammonia Valley” in the pH versus time graphic. The ammonia removal efficiency in SBR was 99% at 20°C. The denitrification reaction was completed when in the ORP versus time graphic appeared the “Nitrate Knee”. From the experimental results the optimisation of the SBR cycle allowed the doubling of the applied load with respect to a not optimised cycle (performed in the same volume reactor), without a decrease in the removal efficiency. Moreover, the possibility of stopping the aeration just after the appearance of the Ammonia Valley allows an energy saving. The easy operation and the low cost make the SBR system an interesting option for the biological pre-treatment of plywood industry to be discharged into surface water.

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Low cost-sensors as a real alternative to on-line nitrogen analysers in continuous systems

Water Science & Technology ◽

10.2166/wst.2009.607 ◽

2009 ◽

Vol 60 (12) ◽

pp. 3261-3268 ◽

Cited By ~ 14

Author(s):

M. V. Ruano ◽

J. Ribes ◽

A. Seco ◽

J. Ferrer

Keyword(s):

Nitrogen Removal ◽

Low Cost ◽

Biological Nitrogen Removal ◽

Attractive Alternative ◽

Continuous Systems ◽

Advanced Control ◽

Nitrification Process ◽

On Line ◽

Anoxic Zones ◽

Biological Nitrogen

This paper is focused on the evaluation of the applicability of low-cost sensors (pH and ORP) versus nutrient analysers for controlling biological nitrogen removal in WWTPs. A nutrient removal pilot plant located in Carraixet WWTP (Valencia, Spain) that is equipped with a significant number of nutrient analysers and low-cost sensors was used. The relations between reliable, cheap on-line sensors such as pH and ORP (located in anaerobic, anoxic and aerobic zones) and the nitrification/denitrification processes are provided. The nitrification process can be evaluated by measuring the pH difference between the first and last aerobic zones. The denitrification process can be evaluated by measuring the pH difference between the first and last anoxic zones and the ORP in the last anoxic zone. Furthermore, when WWTPs include an anaerobic reactor, the ORP in the anaerobic zone can also be used. With all these factors in mind, these sensors give valuable information for applying advanced control systems such as fuzzy logic-based controllers. Also, low-cost sensors involve lower investment, maintenance and operational costs and lower energy consumption derived from aeration and pumping than nutrient analysers. Thus, low-cost sensors can be successfully used as an attractive alternative to nutrient analysers to control biological nitrogen removal in WWTPs.

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Biological nitrogen removal from municipal landfill leachate: low-cost nitrification in biofilters and laboratory scale in-situ denitrification

Water Research ◽

10.1016/s0043-1354(02)00129-x ◽

2002 ◽

Vol 36 (16) ◽

pp. 4079-4087 ◽

Cited By ~ 141

Author(s):

J.P.Y Jokela ◽

R.H Kettunen ◽

K.M Sormunen ◽

J.A Rintala

Keyword(s):

Nitrogen Removal ◽

Landfill Leachate ◽

Low Cost ◽

Laboratory Scale ◽

Biological Nitrogen Removal ◽

Municipal Landfill ◽

Biological Nitrogen

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Enhancing biological nitrogen removal in a small wastewater treatment plant by regulating the air supply

Water Science & Technology ◽

10.2166/wst.2004.0893 ◽

2004 ◽

Vol 48 (11-12) ◽

pp. 445-452 ◽

Cited By ~ 2

Author(s):

M. Fiter ◽

J. Colprim ◽

M. Poch ◽

I. Rodríguez-Roda

Keyword(s):

Wastewater Treatment ◽

Dissolved Oxygen ◽

Nitrogen Removal ◽

Wastewater Treatment Plant ◽

Low Cost ◽

Treatment Plant ◽

Biological Nitrogen Removal ◽

Air Supply ◽

Safety Margins ◽

Biological Nitrogen

Most of the small wastewater treatment plants in Catalonia were not designed to remove nutrients. However, the large safety margins built into their original engineering design has meant that, in many cases, it has been possible to remove part of the nitrogen without being controlled. This paper focuses on the practical experience carried out in one of these facilities, the Bisbal wastewater treatment plant, aimed at enhancing the biological nitrogen removal using simple, low-cost, easy-to-operate measurement and control. The control strategy, which is based on air supply regulation, was previously designed using simulation studies. A dissolved oxygen monitoring system was installed into the facility, while nitrogen concentrations were analysed every day. Optimal dissolved oxygen profiles in the oxidation ditch were identified, while the air supply strategy was modified according to the variations in the influent.

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INTERACTION BETWEEN COMPUTER SIMULATIONS AND CONTROL USING ON-LINE NITROGEN MEASUREMENTS

Water Science & Technology ◽

10.2166/wst.1994.0190 ◽

1994 ◽

Vol 30 (4) ◽

pp. 199-206

Author(s):

Dines E. Thornberg ◽

Henrik A. Thomsen

Keyword(s):

Mathematical Models ◽

Computer Simulations ◽

Nitrogen Removal ◽

Biological Nitrogen Removal ◽

Aeration Tank ◽

Oxygen Control ◽

On Line ◽

Biological Nitrogen ◽

And Control ◽

Influent Wastewater

Mathematical models are a useful tool to help in the prediction of results of operation changes in activated sludge plants. Some calibration of the models is usually necessary, but there is often a lack of data describing the influent wastewater sufficiently. Combining the modelling with continuous measurements of ammonia and nitrate gives a good basis of data in connection with biological nitrogen removal. In this study, phased oxygen control is introduced in a recirculation plant and on-line ammonia measurements in the aeration tank are used to estimate the variations in influent load. After the influent is described the calibration of process constants is done using the on-line data. The calibrated model is used to test the effect of varying recirculation and phase lengths. A mobile monitoring station supplied the on-line data of ammonia and nitrate.

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Effects of HRT on biological nitrogen removal in single-stage autotrophic process

Applied Environmental Biotechnology ◽

10.18063/aeb.2016.02.003 ◽

2016 ◽

Vol 1 (2) ◽

pp. 18 ◽

Cited By ~ 2

Author(s):

Hong Liang ◽

Shutong Liu ◽

Xue Li ◽

Xueying Sun ◽

Dawen Gao

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Removal Rate ◽

Batch Reactor ◽

Ammonia Removal ◽

Nitrogen Loading ◽

Single Stage ◽

Biological Nitrogen Removal ◽

External Circulation ◽

Biological Nitrogen

An external circulation Sequencing Batch Reactor (ecSBR) was used to study the efficiency of nitrogen removal by autotrophic microbe. With gradually reducing the dissolved oxygen (DO) concentration from 1.2 mg/L to 0.04 mg/L, the single-stage autotrophic biological nitrogen removal (sABNR) process could be operated stably. After removing the aeration, the process could still stay sABNR stably, and the concentration of NH4+-N was 0.9 mg/L in effluent, the rate of nitrate (produced)/NH4+-N (removed) was in the range of 0.12–0.40. The results showed that the concentration of NH4+-N in effluent was 0.8, 0.8 and 9.9 mg/L with the hydraulic retention time (HRT) at 8 h, 6 h and 4 h respectively, the removal efficiency of ammonia were 98.2%, 98.1% and 73.6% respectively. The rate of nitrate (produced)/NH4+-N (consumed) was 0.05 at HRT 6 h, and the nitrogen loading rate (NLR) and nitrogen removal rate (NRR) were 169.7 and 129.7 g/m3/d, the removal efficiency of total nitrogen (TN) was 77.5%. In conclusion the optimal HRT was 6 h instead of 8 h or 4 h enough for ammonia removal without causing energy wastage.

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