Recycling of waste water observation
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Answer:
Inria
Team MERE
Members
Overall Objectives
Microbial ecology for environmental preservation
Highlights
Scientific Foundations
Bioprocess engineering and mathematical ecology
Markovian modeling, simulation-based inference and decision
Application Domains
Process engineering tools for the understanding of complex biosystems
Observation and control of waste-water treatment plants
Interpretation of molecular techniques in microbial ecology
Modeling and inference of ecological and environmental dynamics
Software
VITELBIO
New Results
Theoretical results
Applications
Contracts and Grants with Industry
BioInh
CAFE
DIMIMOS
DISCO
MODECOL
RNSC – appel à idées
VITELBIO
International Initiatives
Dissemination
Animation of the scientific community
Teaching
Bibliography
Major publications
Publications of the year
References in notes
Inria / Raweb 2010
Presentation of the Project MERE
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Section: Application Domains
Observation and control of waste-water treatment plants
Control problems frequently arise in the context of the study of biological systems such as wastewater treatment plants. In general, in order to cope with disturbances, modeling errors or parameter uncertainty, one has to take advantage of robust nonlinear control design techniques. These methods are based on central theories of modern nonlinear control analysis, such as disturbance attenuation of Lyapunov functions.
Wastewater treatment plants are often unstable as soon as bacteria growths exhibit some inhibition. Typically, under a constant feed rate, the washout of the reactor (i.e., when biomass is no longer present) becomes an attracting but undesirable equilibrium point. Choosing the dilution rate as the manipulated input is usually a mean for the stabilization about a desired set point, but the most efficient control laws often require a perfect knowledge of the state variables of the system, namely the online measurement of all variable concentrations, which are generally not accessible (for technical or economical reasons). Most often, only few sensors are available.
A popular way to achieve stabilization of a control dynamical system under partial knowledge of the state consists (i) first in designing an "observer" or "software sensor" for the reconstruction of the unobserved variables, and (ii) in a second step, in coupling this estimate with a stabilizing feedback control law, if some "separat delivered by the sensors. During the startup of the process, the system can be far away from the nominal state, where few empirical data are available. Generally, probabilistic hypotheses cannot be justified regarding the nature of the uncertainty for stochastic models to be considered. On the opposite, reasonable bounds on the unknown parts of the models are available, so that uncertainties can be considered as unknown deterministic inputs. Consequently, robust observers and control laws need to be developed to cope with the particularities of the uncertainty on the models. The search for new configurations of processes as well as for innovative control actions is also an
Answer:
Water reuse (also commonly known as water recycling or water reclamation) reclaims water from a variety of sources then treats and reuses it for beneficial purposes such as agriculture and irrigation, potable water supplies, groundwater replenishment, industrial processes, and environmental restoration.