Automatic control system for cooling towers

Claim 3

In a fluid-cooling system of the recirculation type, a pump for pumping cooling fluid through said system, programmable control means for cleaning and treating said system on a periodic basis, a filtering medium operatively connected in said system, said control means further comprising a program-controlled multiposition valve operatively connected to said filtering medium to normally filter the fluid passing therethrough, said control valve being further operative to periOdically backwash said filter by reversing the direction of flow of the fluid passing through said filtering medium and discharge from the system the fluid used for backwashing purposes, means to add makeup fluids to the system, said last named means including said multiposition valve being further operative upon the completion of each such backwash operation to initiate the addition of chemical additives to the system for a predetermined time, and means including said program-controlled multiposition valve operative upon the completion of said chemical additive cycle to initiate a rinse cycle during which contaminated fluids in addition to those discharged from the system during the backwash operation are blead off from the system whereby the chemical composition of said cooling fluid may be maintained at essentially a constant value.

Claim 4

In a fluid-cooling system of the recirculation type, a pump for pumping cooling fluid through said system, programmable control means for cleaning and treating said system on a periodic basis, a filtering medium operatively connected in said system, said control means further comprising a program-controlled multiposition valve operatively connected to said filtering medium to normally filter the fluid passing therethrough, said control valve being further operative to periOdically backwash said filter by reversing the direction of flow of the fluid passing through said filtering medium and discharge from the system the fluid used for backwashing purposes, means to add makeup fluids to the system, said last named means including said multiposition valve being further operative upon the completion of each such backwash operation to initiate the addition of chemical additives to the system for a predetermined time, and means including said program-controlled multiposition valve operative upon the completion of said chemical additive cycle to initiate a rinse cycle during which contaminated fluids in addition to those discharged from the system during the backwash operation are blead off from the system whereby the chemical composition of said cooling fluid may be maintained at essentially a constant value.

Claim 5

In a fluid-cooling system of the recirculation type, a primary flow path including a cooling tower and a load, a pump positioned in said primary flow path for forcibly circulating cooling fluid through said cooling tower and said load, a secondary flow path connected to said primary flow path and continuously diverting a portion of the cooling fluid therefrom, a programmable control valve positioned in said secondary flow path, said control valve having a plurality of orifices and means for independently gating fluid therethrough, means for conducting fluids diverted into said secondary flow path through a first one of said orifices and into said control valve, a filter having an inlet and outlet, means connecting a second orifice of said control valve to the inlet of said filter and a third orifice of said control valve to the outlet of said filter, a line connected to a fourth orifice of said control valve for returning fluids directed therethrough to the primary flow path, a fifth orifice of said control valve being connected to a drain; said control valve being normally operative to conduct fluids entering said control valve via said first orifice therethrough to said second orifice and from thence into the inlet side of said filter and for returning filtered fluids to said control valve via the outlet side of said filter and said third orifice, and from thence to the primary flow path by way of said fourth orifice and the associated return line of said secondary flow path; said control valve being periodically reset to cause fluids which enter the control valve via said first orifice to pass into said filter via the third orifice and to reenter the control valve via the second orifice and to be thereafter discharged from the system via said fifth orifice which is in turn connected to the drain; said control valve being further provided with a sixth orifice, and means connected to said sixth orifice to initiate the transfer of chemicals from a suitable supply to the secondary flow path and from thence to the primary flow path of said fluid-cooling system.

Claim 6

In a fluid-cooling system of the recirculation type, a primary flow path including a cooling tower and a load, a pump positioned in said primary flow path for forcibly circulating cooling fluid through said cooling tower and said load, a secondary flow path connected to said primary flow path and continuously diverting a portion of the cooling fluid therefrom, a programmable control valve positioned in said secondary flow path, said control valve having a plurality of orifices and means for independently gating fluid therethrough, means for conducting fluids diverted into said secondary flow path through a first one of said orifices and into said control valve, a filter having an inlet and outlet, means connecting a second orifice of said control valve to the inlet of said filter and a third orifice of said control valve to the outlet of said filter, a line connected to a fourth orifice of said control valve for returning fluids directed therethrough to the primary flow path, a fifth orifice of said control valve being connected to a drain; said control valve being normally operative to conduct fluids entering said control valve via said first orifice therethrough to said second orifice and from thence into the inlet side of said filter and for returning filtered fluids to said control valve via the outlet side of said filter and said third orifice, and from thence to the primary flow path by way of said fourth orifice and the associated return line of said secondary flow path; said control valve being periodically reset to cause fluids which enter the control valve via said first orifice to pass into said filter via the third orifice and to reenter the control valve via the second orifice and to be thereafter discharged from the system via said fifth orifice which is in turn connected to the drain; said control valve being further provided with a sixth orifice, and means connected to said sixth orifice to initiate the transfer of chemicals from a suitable supply to the secondary flow path and from thence to the primary flow path of said fluid-cooling system.