Abstract: A system for chlorination of a fluid to be treated, which includes a container containing trichlorocyanuric acid in a solid and compact form, a first pipe for supplying the container with dissolving fluid, an evacuation pipe in which the chlorinated fluid circulates, connecting the container to a pipe which contains the fluid to be treated, a chlorine analyzer connected to the pipe and which includes a mechanism for continuously measuring the amount of active chlorine in the treated fluid and released constantly by direct contact of the fluid to be treated with a surface of the trichlorocyanuric acid; and a flow rate regulation mechanism connected to a supply and including a mechanism to for constantly varying a continuous flow rate of the dissolving fluid passing into the container as a function of the amount of active chlorine present in the treated fluid and measured by the chlorine analyzer.