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J Suescun

Publications and source records attributed to J Suescun.

7 recordsLinked to original sources
PubMed2006

Supervisory control strategies for the new WWTP of Galindo-Bilbao: the long run from the conceptual design to the full-scale experimental validation.

This paper presents the theoretical basis and the main results obtained during the development and full-scale experimental validation of the new supervisory control strategy designed for the Galindo-Bilbao wastewater treatment plant (WWTP). The different phases of the project have been carried out over the last 8 years, combining model simulations, pilot-plant experimentation and full-scale validation. The final control strategy combines three complementary control loops to optimise the nitrogen removal in pre-denitrifying activated sludge plants. The first controller was designed to maintain the average concentration of the ammonia in the effluent via the automatic selection of the most appropriate DO set point in the aerobic reactors. The second control loop optimises the use of the denitrification potential and finally, the third control loop maintains the selected amount of biomass in the biological reactors by automatic manipulation of the wastage rate. Mobile-averaged windows have been implemented to incorporate commonly used averaged values in the control objectives. The performance of the controllers has been successfully assessed through the full-scale experimental validation in one of the lines of the WWTP.

Air Movements↗
PubMed2003

Optimizing nitrogen removal in the BioDenitro process.

The potential and limits of different configurations of the BioDenitro-alternating process to suit the various design cases that can arise depending on the wastewater characteristics, space necessary and effluent nitrogen requirements were analysed through simulations of the activated sludge model No. 2. The first analysis involved the combination in one cycle of the main phase in the alternating reactors with an aerated phase having the two reactors in aerobic conditions and/or a hydraulic phase using the flow only in the anoxic reactor. This option has been found to have a very high potential for cases with strict requirements concerning effluent total nitrogen, but limited when the requirements are low effluent NH4-N, relatively high effluent total nitrogen and minimum solids and hydraulic retention times. When the latter conditions have to be fulfilled the incorporation of a post-aeration reactor to the alternating reactor was found to be very effective. In addition the configuration is very flexible because multiple combinations of post-aeration reactor volumes and in the duration of the different phases in the alternating reactors can be selected to achieve effluent nitrogen requirements. This flexibility is limited to the use of moderate values in the post-aeration reactor volumes and in the duration of the aerated phase. An experimental trial of the latter configuration was carried out and demonstrated its operational simplicity by achieving the desired nitrogen requirements in the effluent simply by changing the duration of the aerated phase for a given post-aeration reactor volume. From the experimental results an enhanced simultaneous nitrification-denitrification at the start of aeration in the alternating reactors was found and the ASM2 model was shown to have a satisfactory predictive capacity.

Bioreactors↗
PubMed2002

Practical identification of the dissolved oxygen dynamic in activated sludge plants.

This paper presents the application to a full-scale waste water treatment plant (WWTP) of a practical methodology to identify the oxygen supply and consumption terms, which regulate the dynamic behaviour of the dissolved oxygen concentration (S(O)) in activated sludge reactors. This methodology is based on a periodic adjustment of the selected model for oxygen mass-transfer coefficient (K(L)a) and a continuous estimation of the oxygen uptake rate (r(O)), maintaining constant the adjusted K(L)a model, in order to uncouple the effects that the consumption and supply terms have on the S(O) concentration. The adjustment phase of the K(L)a model is based on typified excitations of the system through the aeration system of the plant, which allow the estimation of K(L)a for different values of the aeration intensity parameter, for instance, air flow rate in air diffusion systems, revolution speed in surface aerators, etc. Once the K(L)a model is adjusted, it is possible to evaluate the K(L)a value in process conditions at any time. The continuous estimation of r(O) is carried out starting from the oxygen mass balance in the activated sludge reactor. This practical methodology has been successfully verified in the Badiolegi WWTP in Azpeitia (Spain), which biological process consists of a double stage AB process, with two different aeration systems: fine pore air diffusers in the A-stage and surface aerators in the B-stage.

Bioreactors↗
PubMed2001

Real-time control strategies for predenitrification-nitrification activated sludge plants biodegradation control.

This paper presents the real-time control strategies developed to regulate both the ammonia and nitrate concentration in the effluent of the new Vitoria WWTP (Spain). Nitrate control aims at the optimal use of the denitrification potential at any moment. For this purpose, the proposed control algorithm continuously adapts the internal recycle flow in order to maintain a desired nitrate set-point in the anoxic zone. Ammonia control aims at maintaining the required average concentration of ammonia in the effluent by manipulating the Dissolved Oxygen (DO) set-point. The control strategies have been based on a hierarchical structure where a high-level or supervisory control selects the set-point of the low-level or conventional controllers. The design of the controllers was carried out using the Quantitative Feedback Theory QFT for the design of robust control systems. Moving average values of some variables have been introduced in order to eliminate the perturbations associated with the daily 24-hour profiles. The controllers have been verified using long-time dynamic simulations based on a mathematical model previously calibrated in pilot plant. Influent load and temperature used in the simulations correspond to the real values measured in the full-scale WWTP during 12 months. The results obtained in the simulations show the good performance and stability of the control strategies independently from external disturbances. A short-time experimental verification of the controllers in pilot plant with real wastewater is also presented.

Ammonia↗
PubMed2001

New simulators for the optimum management and operation of wastewater treatment plant.

This paper presents the basic description and the first full-scale implementation of a new kind of simulator specially designed to facilitate and improve the management and operation of modern wastewater treatment plants (WWTP). This new kind of simulator for plant operation is specifically adapted to every WWTP and the software is developed considering the common needs of the operators in plant exploitation. The internal structure of the plant operation simulator is based on a complete connection between the real data and the mathematical model of the plant. The software is then able to perform the processing, storage and management of the plant data and to predict the evolution of the process reading the required inputs from its stored files. The results obtained with the first application recommend the implementation of this new kind of simulators for plant operation in other treatment plants. However, it is important to note that the application of this technology implies a systematic and rigorous methodology in the acquisition and processing of the most significant plant data.

Data Collection↗
PubMed1979

Nutritional supplementation and the outcome of pregnancy. I. Birth weight.

Colombian women at risk of malnutrition were enrolled in a health care program and randomly assigned to supplementation and control groups at the beginning of the third trimester of pregnancy. The net dietary intake increments resulting from supplementation amounted to 155 cal and 20 g of protein per day. Supplementation had a significant effect on the mean birth weight of male infants, but not that of female infants; the mechanisms responsible for the sex differences remain to be elucidated. The randomized trial design of the experiment and the documented similarity between the experimental and control groups at the onset permit the conclusion that the observed differences were caused by the food supplementation program. The effect of supplementation on maternal weight gain and the association of the latter with birth weight strongly suggest that improved maternal nutrition mediated the effect on birth weight.

Birth Weight↗