Short description of atmosphere-type water deaeration system process
Thermal atmosphere deaerator consist of water-jet mixing heat-exchanger and atmosphere cyclone separator.
Deaerator has two-stage of deaeration: 1st stage – chemically cleaned water heating with temperature from 5÷10˚С to 102˚С at water-jet mixing heat-exchanger, 2nd stage – separation of gas-vapor mixture and water in cyclone separator.
Chemically cleaned water flow with temperature 5÷10˚С (or 45÷55 ºC, in case when water goes through the water-moderated heat-exchanger heating by deaerating water after deaerating tank) and with pressure 0,1÷0,3 atm supplies to water-jet mixing heat-exchanger to heat water up to temperature 102˚С and with steam pressure 0,1÷0,4 atm.
Intensive mixing of fast jet water with gas in heat-exchanger mixing chamber form from dissolves gases (О2, СО2) the gas-vapor bubbles. The formed two-phase flow goes to cyclone separator and separates to gas-vapor mix and water. Deaerating water flows to hot well (it volume is (m3) 50% of maximum deaerator water discharge), but evolved gas goes to atmosphere. From hot well deaerating water pumps and then according to layout. The height of hot well must be about 3 m, provided that installed water-moderated hear exchanger will cool the deaerating water to 80ºС temperature with chemically cleaned water. It’s recommended to avoid the deaerating water boiling during pumping.
Water-level control in the hot well realized by control valve, which installed on supply line of chemically cleaned water, which goes to heat-exchanger. Hot well has a pressure-difference transmitter from which current signal goes to PID transmitter regulating the control valve.
Temperature control of chemically cleaned water after heat-exchanger realize by control valve, which installed on gas supply line.
Piping with heated water after heat-exchanger has a temperature transmitter from which current signal goes to PID transmitter regulating the control valve.