住宅中水回收系统示意图

Create a clean technical system diagram of a residential {argument name="system type" default="greywater recycling system"} for toilet flushing. Show {argument name="sources" default="three water sources"} on the left: kitchen vegetable washing sink, bathroom wash basin, and washing machine. Each source connects through a diverter valve to either the original sewer drain or the greywater recycling line. The greywater line goes into a pre-filter module with coarse mesh filter, sediment trap, washable cartridge filter, and grease separator for kitchen water. Then show a low-level greywater collection tank with overflow pipe to sewer, high and low water level sensors, and inspection cover. From this tank, show a greywater transfer pump sending water upward into a large white plastic storage tank. The large tank has low, middle, and high water level sensors, overflow to sewer, drain outlet, optional UV disinfection module, and ventilation. From the storage tank, show a pump or gravity outlet feeding the toilet cistern. Include a backup clean water supply with air gap and backflow prevention to the toilet cistern. Show a {argument name="controller" default="Raspberry Pi 4 controller"} connected with signal lines to sensors, solenoid valves, pumps, leak sensor, and alarm. Use blue arrows for water flow, red arrows for overflow/emergency drain, dotted black lines for electronic control. Style: modern engineering schematic, white background, labeled components, clear arrows, minimal but detailed.