The present invention relates to a method of preparing an alkylated salicylamide from a protected and activated salicylamide via a dicarboxylated salicylamide intermediate. The cleaner incorporates a valve with a hollow domed perforated closure member operating in a body with the valve mounted on a stem carrying a rolling diaphragm or a piston subjected intermittently and automatically to the pressure induced by the filter plant pump. An apparatus and a system are also provided herein.