Automatic addition of a corrosion inhibitor to a coolant system by osmotic pressure

A device for the automatic addition of a corrosion inhibitor into a coolant system having an overflow reservoir to protect a heat exchanger subject to corrosion, comprising a container for a concentrated corrosion inhibitor solution having an upper portion with an overflow tube in the upper end thereof and a lower portion having an opening in the lower end thereof to allow entry of the coolant therein, a semi-permeable osmotic membrane located in the container with its periphery clamped between the container portions to separate the corrosion inhibitor solution from the inhibited coolant, means to clamp the container portions together, and means encompassing said clamping means to cause the container to float in said coolant, the osmotic pressure of the corrosion inhibitor solution being equal to that of the inhibited coolant but less than the osmotic pressure of inhibitor depleted coolant to cause water to pass through the membrane into the corrosion inhibitor solution to force solution from the overflow tube into the body of coolant in the reservoir when there is a difference in osmotic pressures.

A device for the automatic addition of a corrosion inhibitor into a coolant system having an overflow reservoir to protect a heat exchanger subject to corrosion, comprising a container for a concentrated corrosion inhibitor solution having an upper portion with an overflow tube in the upper end thereof and a lower portion having an opening in the lower end thereof to allow entry of the coolant therein, a semi-permeable osmotic membrane located in the container with its periphery clamped between the container portions to separate the corrosion inhibitor solution from the inhibited coolant, said upper container portion having a generally conical wall terminating at the upper end in said overflow tube, and a generally cylindrical wall encompassing the conical wall and abutting the conical wall at its largest diameter, said cylindrical wall providing an upper open end to receive solid corrosion inhibitor therein, the osmotic pressure of the corrosion inhibitor solution being equal to that of the inhibited coolant but less than the osmotic pressure of inhibitor depleted coolant to cause water to pass through the membrane into the corrosion inhibitor solution to force solution from the overflow tube into the body of coolant in the reservoir when there is a difference in osmotic pressures.

A device for the automatic addition of a treating chemical into a solution to be treated, comprising a container for the treating chemical having an upper portion with an overflow tube in the upper end thereof and a lower portion having an opening in the lower end thereof to allow entry of the solution to be treated thereinto, a semi-permeable osmotic membrane located in the container with its periphery clamped between the container portions to separate the treating chemical from the solution to be treated, means encompassing said container to cause the container to float in the solution to be treated with the overflow tube above the level of the solution, the osmotic pressure of the treating chemical being equal to that of the treated solution but less than the osmotic pressure of untreated solution such that the solvent of the solution will pass through the membrane into the treating chemical to force concentrated chemical solution from the overflow tube into the solution to be treated when there is a difference in osmotic pressures.