Patent FR-2924952-A1 (FR)
Title: Autonomous system for potabilizing brackish and/or polluted water, comprises pipes for circulating water, a unit for capturing renewable energy, a unit for controlling electronic and/or informatic set, and an automatic control unit
Inventor: MARCHAND JEAN-JACQUES
IPC: B01D61/06
Filed: 2007-12-17
Abstract: The autonomous system for the potabilization of brackish and/or polluted water, comprises pipes (7) for the circulation of water from an upstream inlet (8a) to two downstream outlets (8b, 8c), a unit for capturing renewable energy such as solar or wind to generate a Ub voltage fluctuating throughout the day and supplying electricity to the pumping unit, a unit for controlling electronic and/or informatic set that are connected to a sensor for measuring the generated voltage at the upstream pumping unit, an automatic control unit, and a voltage stabilizer. The autonomous system for the potabilization of brackish and/or polluted water, comprises pipes (7) for the circulation of water from an upstream inlet (8a) to two downstream outlets (8b, 8c), a unit for capturing renewable energy such as solar or wind to generate a Ub voltage fluctuating throughout the day and supplying electricity to the pumping unit, a unit for controlling electronic and/or informatic set that are connected to a sensor for measuring the generated voltage at the upstream pumping unit, an automatic control unit, and a voltage stabilizer such as a unit for electrochemical or electrostatic energy storage. The upstream inlet is arranged for suction of crude water. One of the outlets is used for treating water and another is used for the discharge of water. The pipes are associated with an upstream pumping unit for the suction and delivery of crude water at the upstream inlet, and a downstream unit for water filtration membrane connected to the downstream outlet for water treatment through an expansion valve. The value for generating the voltage increases for a same level of capturing, when the speed of the pumping unit is decreased and increased. The voltage stabilizer is located between the energy capturing unit and the pumping unit, and is permanently retained at full load or nearly full load. The control unit corresponds to the full load voltage of the stabilizer, or a nominal voltage for functioning the system. The pumping unit consists of a set of two pumps including a downstream lift pump and a downstream booster pump. The control unit is connected to the two pumps. A unit is arranged for measuring the pressure of the supplied water Peb within the pipe extending between the two pumps. The control unit is connected: to the downstream expansion valve; to a water flow sensor Qeb located on a first pipe extending between the pump unit and a filtration unit (3); to downstream of an inlet of a recycling loop; to a water pressure sensor either located on the first pipe for measuring a supplied pressure Pa or a second pipe extending between the filtration unit and the expansion valve for measuring a pressure Pc; to the recirculation pump; and to a sensor of recycling water flow Qrec mounted on recycling loop. The control unit is capable of automatically controlling: the speed of the pumping unit according to a value that allows the generated voltage Ub to achieve and to maintain a voltage set point Ubo; the speed of the upstream lift pump to achieve and to maintain a generated voltage set point Ubo; the speed of the downstream of the booster pump to achieve and to maintain the supplied water pressure set point Pebo corresponding to the optimal functioning value of the downstream pump; the opening of the expansion valve so that the pressure of discharge water Pc or supplied water Pa is maintained at a pressure reference value Pco or Pao; and the speed of the recycling pump so that the recycling rate Qrec achieves and maintains a recycling flow reference value Qreco. The reference value of pressure Pco or Pao varies according to the measured value of feed rate Qeb for obtaining and maintaining a minimum specific energy Wt. The pipes are arranged to form a recycling loop of which the inlet is located between the filtration unit and expansion valve and the outlet is located between the filtration unit and pumping unit. The recycling loop comprises a recirculation pump enhancing the flow of water from the inlet to the outlet. The reference value of flow Qreco varies according to the measured value of the feed rate Qeb for obtaining and maintaining a minimum specific energy Wt. The filtration is carried out by reverse osmosis or by nanofiltration. An independent claim is included for a process for the management of function of an autonomous system for the potabilization of water.