Fluid injector with vent/proportioner ports

A solution dispensing system for dispensing, at a metered rate, a solution into a flow of fluid in a flow line, the solution dispensing system comprising:

• a storage tank for containing the solution;
• a lid adapted to mate with the storage tank, the lid comprising:
• an inlet connection and an outlet connection for accepting fluid diverted from the flow line and for returning fluid to the flow line;
• a crossover connection connecting the inlet connection to the outlet connection providing a fluid flow path that allows fluid diverted from the flow line to move in path that is in parallel with a path of the flow line;
• an agitation tube in fluid communication with the crossover connection proximate to the inlet connection for placing the crossover connection in fluid communication with the storage tank;
• a pickup tube in fluid communication with the crossover connection proximate to the outlet connection for placing the crossover connection in fluid communication with the storage tank;
• and
• a mixing valve associated with the crossover connection intermediate the agitation tube and the pickup tube, the mixing valve being adjustable to control the flow of the fluid diverted from the flow line through the crossover connection and into and out of the storage tank via the agitation tube and the pickup tube.