Name: CONSTANSA VALADARES TRIPOLI
Publication date: 16/12/2020
Advisor:
Name |
Role |
|---|---|
| RICARDO FRANCI GONÇALVES | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| EDUMAR RAMOS CABRAL COELHO | Internal Examiner * |
| RAQUEL MACHADO BORGES | External Examiner * |
| RICARDO FRANCI GONÇALVES | Advisor * |
Summary: Capacitive deionization (CDI) consists of an emerging technology for brackish
water desalination, in which the ions are removed from the water, by means of
an electrosorption process, and adsorbed on the electrode surfaces under the
presence of the electric field, generating a flow of purified water. When the
electrodes are saturated, the polarity of the applied electrical voltage is reversed and the ions contained in the double electrical layer are desorbed, producing a flow of concentrated water.
This technology has advantages, no branch of conventional desalination
technologies, particularly for brackish waters with intermediate salinities,
highlighting the operation at room temperature and low pressures, high water
recovery and no use of chemicals. However, its applicability as an advanced
treatment alternative for sanitary sewage still generates uncertainties, mainly due to the complex composition.
In this study, the evaluation of the performance of desalination under operating
conditions of variable flow during a purification step, with constant flow in the
rejection process, aims to increase the water recovery rates of the system, with electrical adjustments. as the rate of water recovery increased.
Experimentally, it is evident that the increase in the water recovery rate, from the application of greater hydraulic loads during a purification stage, is an addition with reduced performance in the removal of salt. The combination of lower hydraulic loads and water recovery rates shows a tendency for greater ion removal efficiency. Regarding energy consumption by volume of treated water, there is a positive relationship to the increase in hydraulic load and an inverse relationship to the increase in the rate of water recovery.
