The wasted activated sludge (WAS) was sintered with laterite and iron oxide to form porous pellet... more The wasted activated sludge (WAS) was sintered with laterite and iron oxide to form porous pellets which were added into a sequencing batch biofilm reactor (SBBR) in two different filling ratios (20 and 40%) as a cell immobilizing carrier for nitrogen removal. Hydroxylamine (NH2OH) production was used for identifying and modelling the simultaneous nitrification and denitrification (SND) process in SBBR. The results showed that the more NH2OH was released, the more ammonium was converted into nitrite, and the SND nitrogen removal efficiency (ESND) also increased due to higher nitrification rate constant in the system. In the first part of the SND process, the specific NH2OH and NO2 release rates of 9.5 × 10 mg NH2OH g -1 MLSS min and 6.1 × 10 mg NO2 g MLSS min were measured. When the COD/N ratio was 8.1, the removal efficiencies of COD and ammonium were 95 and 98%, respectively. The hydroxylamine and nitrite production rates during the nitrification reaction were 5.8 × 10 mg NH2OH g ...
N 2 O, like CO 2 , H 2 O, and CH 6 , will causes green house effect. This study utilized syntheti... more N 2 O, like CO 2 , H 2 O, and CH 6 , will causes green house effect. This study utilized synthetic wastewater to closed sequencing batch reactor (SBR) to examine the detail N 2 O released mechanisms in each stage of the overall reaction. Manual operated SBR reactor connected with on-line p11, DO and ORP sensors to collect operation parameters. FIM was controlled between 0.11 to 0.44 /Kg-MLSS*d. Since the overall reaction included aerobic and anaerobic stages, ORP was used as one of the monitor and control parameters throughout this study. The higher F/M loading, the higher COD, ammonia removal, nitrification rate (K N ), denitrification rate(K D N ) and N 2 O turnover rate can be obtained. Denitrification reaction released five times the amount of N 2 O than that from nitrification reaction.
Introduction Mathematics is one of the important subjects in our school curriculum. "In the ... more Introduction Mathematics is one of the important subjects in our school curriculum. "In the present quantitatively complex society, a person needs a functional knowledge of mathematical content to make informed decisions as a citizen and as a worker" (Wilkins & Ma, 2003, p. 1). However, Manjul Bhargava, an ace number theorist, who has recently won the Fields Medal, has mentioned that mathematics is taught as a robotic subject (Rajghatta, 2014). This leads the students to struggle in understanding mathematics courses in high school (Offer & Bos, 2009). In fact, mathematics educators are facing one of the major challenges to improve the performance of the students in mathematics (Tan & Tan, 2015). With the rapid advancement in educational technology, many researchers have recommended the use of technology across the mathematics curriculum as it produces positive results in learning and understanding the concepts (Lazakidou & Retalis, 2010; National Council of Teachers of Mat...
Waste activated sludge was collected from the final clarifier of a local municipal wastewater tre... more Waste activated sludge was collected from the final clarifier of a local municipal wastewater treatment plant. NaOH was used in comparison made of the controlled pH batch experiments with those having no pH control. The sludge without pH control would rapidly increase soluble materials. pH control experiments indicate a stable soluble reaction but reaction styles vary with different pH control values. This finding confirms the importance of selecting a suitable pH. The results of solute analysis are satisfactory at pH value of 10.
Journal of Water Supply: Research and Technology-Aqua, 2000
... by Cheng-Nan Chang, Ying-Shih Ma, Guor-Cheng Fang, Fang-Fong Zing. ... Molecular and isotopic... more ... by Cheng-Nan Chang, Ying-Shih Ma, Guor-Cheng Fang, Fang-Fong Zing. ... Molecular and isotopic characterization of the particulate organic matter from an eutrophic coastal bay in SE Brazil. Francine A Kalas, Renato S Carreira, Stephen A Macko, Angela LR Wagener in ...
The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removi... more The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-t...
On-line monitoring of ORP has been proved to be a practical and useful technique for process cont... more On-line monitoring of ORP has been proved to be a practical and useful technique for process control of wastewater treatment systems. This paper presents the feasibility of using on-line ORP monitoring system on a laboratory scale single tank continuous-flow activated sludge batch reactor, which is capable of removing carbon, nitrogen and phosphorus pollutants. Two control strategies, fixed-time and real-time, are applied for process control. Results obtained from fixed-time control study indicate that the variations and the ORP profile can accurately represent dynamic characteristics of system; the pH profile can also indicate some of those characteristics. Also, the breakpoints, setpoints and settime on the ORP and pH profiles are used to establish the real-time control strategy to determine the transfer of operation stages. The real-time experiments show a better performance than fixed-time, thus, on-line ORP and pH monitoring and control is practical for continuous-flow batch activated sludge process control.
... GUOR-CHENG FANGa,*, CHENG-NAN CHANGb, SHIN-CHUNG LIT, YUH-SHEN WUa,SHUN-CHIN CHENb and CHII-D... more ... GUOR-CHENG FANGa,*, CHENG-NAN CHANGb, SHIN-CHUNG LIT, YUH-SHEN WUa,SHUN-CHIN CHENb and CHII-DONG CHENGb ... Environ., 28(6), 1175-1179 (1994). [2] KS Chen and GF Lin, The characteristics and sources of PM2.5 in the ambient air in Kau-Shung. ...
Ratio of total Kjeldahl Nitrogen to COD for ABS (acrylnitrile, butadiene and styrene) wastewater ... more Ratio of total Kjeldahl Nitrogen to COD for ABS (acrylnitrile, butadiene and styrene) wastewater is in a range of 0.12–0.17, which is significantly higher than that needed for optimal growth of an activated sludge. In this work, an automated Sequencing Batch Biofilm Reactor (SBBR) system at lab-scale is applied to reduce the amount of ABS; this system is controlled by an on-line monitoring of oxidation-reduction potential (ORP). A comparison of the operation efficiency for the lab-scale SBBR operated with the control of fix-time method and ORP-based real-time automatic method is presented. The results show that the system ORP can be used as an available parameter for achieving a real-time operation and control of the lab-scale SBBR. It is found that the reaction time is reduced of 11.1–55.2% if an ORP-based real-time control is used, instead of the fixed-time control. Also, the SBBR system is made more efficient and cost-effective.
ABSTRACTThis experiment was conducted during November in 2000 and February in 2001 in Taichung, c... more ABSTRACTThis experiment was conducted during November in 2000 and February in 2001 in Taichung, central Taiwan. The study used a TE-PUF sampler, Universal air sampler and MOUDI (Micro-Orifice Uniform Deposit Impactor) sampler to collect the ambient air suspended particles and analyzed their water-soluble ions (Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+ and Ca2+). Analytical results indicate that the mean mass concentration for PM2.5, PM2.5-10 and TSP measured at the CCRT (traffic) sampling site are 54.5, 27.8 and 158 μm/m3, respectively. Additionally, the mean mass concentration for PM2.5, PM2.5-10 and TSP measured at the THUC sampling site are 23.6, 16.3 and 85.6 μm/m3, respectively. Furthermore, the major water-soluble ion of PM2.5 measured in this sampling region are SO42- and NH4+, while those of PM2.5-10 are Cl-, NO3- and SO42-, respectively. At the CCRT (traffic) sampling site, the mean size distributions of mass, SO42- and NH4+ exhibit a bimodal distribution whereas those of Cl-, NO3-, Na+, K+, Mg2+ and Ca2+ have a bimodal distribution. At the THUC (campus) sampling site, the mean size distributions of mass, Cl-, NO3-, SO42- and Ca2+ are bimodal whereas those of Na+, NH4+, K+ and Mg2+ have display a unimodal distribution.
Water science and technology : a journal of the International Association on Water Pollution Research, 2001
The purpose of this study is to develop a reliable and effective real-time control strategy by in... more The purpose of this study is to develop a reliable and effective real-time control strategy by integrating artificial neural network (ANN) process models to perform automatic operation of a dynamic continuous-flow SBR system. The ANN process models, including ORP/pH simulation models and water quality ([NH4(+)-N] and [NOx(-)-N]) prediction models, can assist in real-time searching the ORP and pH control points and evaluating the operation performances of aerobic nitrification and anoxic denitrification operation phases. Since the major biological nitrogen removal mechanisms were controlled at nitrification (NH4(+)-N-->NO2(-)-N) and denitritification (NO2(-)-N-->N2) stages, as well as the phosphorus uptake and release could be completely controlled during aerobic and anoxic operation phases, the system operation performances under this ANN real-time control system revealed that both the aeration time and overall hydraulic retention time could be shortened to about 1.9-2.5 and 4...
The wasted activated sludge (WAS) was sintered with laterite and iron oxide to form porous pellet... more The wasted activated sludge (WAS) was sintered with laterite and iron oxide to form porous pellets which were added into a sequencing batch biofilm reactor (SBBR) in two different filling ratios (20 and 40%) as a cell immobilizing carrier for nitrogen removal. Hydroxylamine (NH2OH) production was used for identifying and modelling the simultaneous nitrification and denitrification (SND) process in SBBR. The results showed that the more NH2OH was released, the more ammonium was converted into nitrite, and the SND nitrogen removal efficiency (ESND) also increased due to higher nitrification rate constant in the system. In the first part of the SND process, the specific NH2OH and NO2 release rates of 9.5 × 10 mg NH2OH g -1 MLSS min and 6.1 × 10 mg NO2 g MLSS min were measured. When the COD/N ratio was 8.1, the removal efficiencies of COD and ammonium were 95 and 98%, respectively. The hydroxylamine and nitrite production rates during the nitrification reaction were 5.8 × 10 mg NH2OH g ...
N 2 O, like CO 2 , H 2 O, and CH 6 , will causes green house effect. This study utilized syntheti... more N 2 O, like CO 2 , H 2 O, and CH 6 , will causes green house effect. This study utilized synthetic wastewater to closed sequencing batch reactor (SBR) to examine the detail N 2 O released mechanisms in each stage of the overall reaction. Manual operated SBR reactor connected with on-line p11, DO and ORP sensors to collect operation parameters. FIM was controlled between 0.11 to 0.44 /Kg-MLSS*d. Since the overall reaction included aerobic and anaerobic stages, ORP was used as one of the monitor and control parameters throughout this study. The higher F/M loading, the higher COD, ammonia removal, nitrification rate (K N ), denitrification rate(K D N ) and N 2 O turnover rate can be obtained. Denitrification reaction released five times the amount of N 2 O than that from nitrification reaction.
Introduction Mathematics is one of the important subjects in our school curriculum. "In the ... more Introduction Mathematics is one of the important subjects in our school curriculum. "In the present quantitatively complex society, a person needs a functional knowledge of mathematical content to make informed decisions as a citizen and as a worker" (Wilkins & Ma, 2003, p. 1). However, Manjul Bhargava, an ace number theorist, who has recently won the Fields Medal, has mentioned that mathematics is taught as a robotic subject (Rajghatta, 2014). This leads the students to struggle in understanding mathematics courses in high school (Offer & Bos, 2009). In fact, mathematics educators are facing one of the major challenges to improve the performance of the students in mathematics (Tan & Tan, 2015). With the rapid advancement in educational technology, many researchers have recommended the use of technology across the mathematics curriculum as it produces positive results in learning and understanding the concepts (Lazakidou & Retalis, 2010; National Council of Teachers of Mat...
Waste activated sludge was collected from the final clarifier of a local municipal wastewater tre... more Waste activated sludge was collected from the final clarifier of a local municipal wastewater treatment plant. NaOH was used in comparison made of the controlled pH batch experiments with those having no pH control. The sludge without pH control would rapidly increase soluble materials. pH control experiments indicate a stable soluble reaction but reaction styles vary with different pH control values. This finding confirms the importance of selecting a suitable pH. The results of solute analysis are satisfactory at pH value of 10.
Journal of Water Supply: Research and Technology-Aqua, 2000
... by Cheng-Nan Chang, Ying-Shih Ma, Guor-Cheng Fang, Fang-Fong Zing. ... Molecular and isotopic... more ... by Cheng-Nan Chang, Ying-Shih Ma, Guor-Cheng Fang, Fang-Fong Zing. ... Molecular and isotopic characterization of the particulate organic matter from an eutrophic coastal bay in SE Brazil. Francine A Kalas, Renato S Carreira, Stephen A Macko, Angela LR Wagener in ...
The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removi... more The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-t...
On-line monitoring of ORP has been proved to be a practical and useful technique for process cont... more On-line monitoring of ORP has been proved to be a practical and useful technique for process control of wastewater treatment systems. This paper presents the feasibility of using on-line ORP monitoring system on a laboratory scale single tank continuous-flow activated sludge batch reactor, which is capable of removing carbon, nitrogen and phosphorus pollutants. Two control strategies, fixed-time and real-time, are applied for process control. Results obtained from fixed-time control study indicate that the variations and the ORP profile can accurately represent dynamic characteristics of system; the pH profile can also indicate some of those characteristics. Also, the breakpoints, setpoints and settime on the ORP and pH profiles are used to establish the real-time control strategy to determine the transfer of operation stages. The real-time experiments show a better performance than fixed-time, thus, on-line ORP and pH monitoring and control is practical for continuous-flow batch activated sludge process control.
... GUOR-CHENG FANGa,*, CHENG-NAN CHANGb, SHIN-CHUNG LIT, YUH-SHEN WUa,SHUN-CHIN CHENb and CHII-D... more ... GUOR-CHENG FANGa,*, CHENG-NAN CHANGb, SHIN-CHUNG LIT, YUH-SHEN WUa,SHUN-CHIN CHENb and CHII-DONG CHENGb ... Environ., 28(6), 1175-1179 (1994). [2] KS Chen and GF Lin, The characteristics and sources of PM2.5 in the ambient air in Kau-Shung. ...
Ratio of total Kjeldahl Nitrogen to COD for ABS (acrylnitrile, butadiene and styrene) wastewater ... more Ratio of total Kjeldahl Nitrogen to COD for ABS (acrylnitrile, butadiene and styrene) wastewater is in a range of 0.12–0.17, which is significantly higher than that needed for optimal growth of an activated sludge. In this work, an automated Sequencing Batch Biofilm Reactor (SBBR) system at lab-scale is applied to reduce the amount of ABS; this system is controlled by an on-line monitoring of oxidation-reduction potential (ORP). A comparison of the operation efficiency for the lab-scale SBBR operated with the control of fix-time method and ORP-based real-time automatic method is presented. The results show that the system ORP can be used as an available parameter for achieving a real-time operation and control of the lab-scale SBBR. It is found that the reaction time is reduced of 11.1–55.2% if an ORP-based real-time control is used, instead of the fixed-time control. Also, the SBBR system is made more efficient and cost-effective.
ABSTRACTThis experiment was conducted during November in 2000 and February in 2001 in Taichung, c... more ABSTRACTThis experiment was conducted during November in 2000 and February in 2001 in Taichung, central Taiwan. The study used a TE-PUF sampler, Universal air sampler and MOUDI (Micro-Orifice Uniform Deposit Impactor) sampler to collect the ambient air suspended particles and analyzed their water-soluble ions (Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+ and Ca2+). Analytical results indicate that the mean mass concentration for PM2.5, PM2.5-10 and TSP measured at the CCRT (traffic) sampling site are 54.5, 27.8 and 158 μm/m3, respectively. Additionally, the mean mass concentration for PM2.5, PM2.5-10 and TSP measured at the THUC sampling site are 23.6, 16.3 and 85.6 μm/m3, respectively. Furthermore, the major water-soluble ion of PM2.5 measured in this sampling region are SO42- and NH4+, while those of PM2.5-10 are Cl-, NO3- and SO42-, respectively. At the CCRT (traffic) sampling site, the mean size distributions of mass, SO42- and NH4+ exhibit a bimodal distribution whereas those of Cl-, NO3-, Na+, K+, Mg2+ and Ca2+ have a bimodal distribution. At the THUC (campus) sampling site, the mean size distributions of mass, Cl-, NO3-, SO42- and Ca2+ are bimodal whereas those of Na+, NH4+, K+ and Mg2+ have display a unimodal distribution.
Water science and technology : a journal of the International Association on Water Pollution Research, 2001
The purpose of this study is to develop a reliable and effective real-time control strategy by in... more The purpose of this study is to develop a reliable and effective real-time control strategy by integrating artificial neural network (ANN) process models to perform automatic operation of a dynamic continuous-flow SBR system. The ANN process models, including ORP/pH simulation models and water quality ([NH4(+)-N] and [NOx(-)-N]) prediction models, can assist in real-time searching the ORP and pH control points and evaluating the operation performances of aerobic nitrification and anoxic denitrification operation phases. Since the major biological nitrogen removal mechanisms were controlled at nitrification (NH4(+)-N-->NO2(-)-N) and denitritification (NO2(-)-N-->N2) stages, as well as the phosphorus uptake and release could be completely controlled during aerobic and anoxic operation phases, the system operation performances under this ANN real-time control system revealed that both the aeration time and overall hydraulic retention time could be shortened to about 1.9-2.5 and 4...
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