Modelling and PI Control of an Irrigation Canal

The main goal of this paper is to expose and validate a methodology to design efficient automatic controllers for irrigation canals, based on the Saint-Venant model. This model-based methodology enables to design controllers at the design stage (when the canal is not already built). The methodology is applied on an experimental canal located in Portugal. First the full nonlinear PDE model is calibrated, using a single steady-state experiment. The model is then linearized around a functioning point, in order to design linear PI controllers. Two classical control strategies are tested (local upstream control and distant downstream control) and compared on the canal. The experimental results show the effectiveness of the model.

Modeling, control and field tests on an experimental irrigation canal

Irrigation canals are complex hydraulic systems difficult to control. Many models and control strategies have already been developed using linear control theory. In the present study, a PI controller is developed and implemented in a brand new prototype canal and its features evaluated experimentally. The base model relies on the linearized Saint-Venant equations which is compared with a reservoir model to check its accuracy. This technique will prove its capability and versatility in tuning properly a controller for this kind of systems.

Adsorption of pesticides onto activated carbons from wood composites

A series of activated carbon was produced from particleboard and medium-density fibreboard monoliths, which are waste originated from the industry, and then characterized and evaluated for potential application for phenoxyacetic acids removals, such 2,4-dichlorophenoxyacetic acid (2,4-D), 2-methyl-4-chlorophenoxy acetic acid (MCPA) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), from the liquid phase. All AC retain the shape of the precursor, and displays a microporous structure well-developed, reaching 0.58 cm 3 g -1. The adsorption isotherms for three pesticides were obtained in the optimal conditions and the AC with high superficial area and micropore volume exhibited better performance, allowing to state that, this AC could be a great substitute of those habitually used for this purpose. The pesticides adsorption data were linearized using the Langmuir and Freundlich equation, being the first a very good fit to the experimental data.

Adsorption of pesticides onto activated carbons from wood composites

A series of activated carbon was produced from particleboard and medium-density fibreboard monoliths, which are waste originated from the industry, and then characterized and evaluated for potential application for phenoxyacetic acids removals, such 2,4-dichlorophenoxyacetic acid (2,4-D), 2-methyl-4-chlorophenoxy acetic acid (MCPA) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), from the liquid phase. All AC retain the shape of the precursor, and displays a microporous structure well-developed, reaching 0.58 cm 3 g -1. The adsorption isotherms for three pesticides were obtained in the optimal conditions and the AC with high superficial area and micropore volume exhibited better performance, allowing to state that, this AC could be a great substitute of those habitually used for this purpose. The pesticides adsorption data were linearized using the Langmuir and Freundlich equation, being the first a very good fit to the experimental data.