Contaminant Control System in an Evaporative Water Treating System

A contaminant control system for an evaporative water purification process in a SAGD (Steam Assisted Gravity Drainage) system for a heavy oil recovery facility, the system comprising of an evaporator and a set of controllers;

• the evaporator having a bottom with a sump provided at the bottom thereof and including an oil skimming weir dividing the sump into a main sump and a blowdown sump, wherein water containing impurities flows over the weir from the main sump to the blowdown sump;
• in a normal operation mode, the evaporator receiving water from the process and discharging distilled water from a distillate tank and discharging waste brine from the blowdown sump;
• the set of controllers including:
• a distilled water flow meter provided at the discharge of evaporator,
• a blowdown flow meter measuring the flow from the main sump to the blowdown sump,
• a cycle calculator for calculating the ratio between the distilled water flow and blowdown flow and a total flow controller;
• wherein the cycle calculator provides a set point to the total flow controller, thus the flow of the water into the evaporator does not directly depend on the level of the liquid in the main sump;
• wherein the operation of the evaporator functions in a contained closed loop environment.