There is provided a process for controllably supplying a chemical agent to a flowing process fluid for effecting generation of treated flowing fluid comprising a chemical agent-derived fluid component material, wherein the chemical agent-derived fluid component material is derived from the chemical agent. The controllably supplying comprises: while discharging a chemical agent from a chemical agent supply system, modulating distribution of the chemical agent that is being discharged, between at least a flowing process fluid and a fluid bypass, with a chemical agent supply modulation system, in accordance with a system operating cycle, wherein the system operating cycle includes a single system supply mode and a single system bypass mode, and wherein the system bypass mode follows the system supply mode.