Water Reuse Ratio<\/strong><\/p>\nThe fraction of total water used on site that is recovered and put back into the process. A well-run ZLD plant can push this above 95%. A plant that relies on once-through cooling is likely below 30%. Measurement requires accurate flow on both freshwater intake and recovered loops.<\/p>\n
Net Freshwater Intake<\/strong><\/p>\nTotal freshwater drawn from external sources per unit of production. This is the metric that regulators most often set targets against. In the EU and California, water-stressed industries face progressively lower allowed intake as 2026 regulations tighten.<\/p>\n
Freshwater Intensity per Unit of Production<\/strong><\/p>\nA normalized metric that lets investors compare sites with different output. For petrochemical refining, typical targets are 1\u20133 m\u00b3 of freshwater per ton of product. For data centers, the metric is liters per kilowatt-hour of computing output.<\/p>\n
Discharge Quality Index<\/strong><\/p>\nA composite metric of key effluent parameters (TDS, COD, SS, pH) versus regulatory limits. It captures how close the plant runs to its limits, not just whether it is compliant. A lower discharge quality index reflects better control and lower regulatory risk.<\/p>\n
Internal Water Cost<\/strong><\/p>\nTotal cost of water management per unit of production, including freshwater purchase, chemical dosing, energy for treatment, membrane replacement, and disposal fees. This is the cost metric that finance teams increasingly want to see alongside ESG metrics.<\/p>\n
<\/span>Measurement Stacks That Back Each KPI<\/span><\/h2>\nEach KPI needs a specific sensor stack:<\/p>\n
\n\n\n| KPI<\/th>\n | Required Sensor Stack<\/th>\n<\/tr>\n<\/thead>\n |
\n\n| Water reuse ratio<\/td>\n | Flow meters on intake and every recycle loop<\/td>\n<\/tr>\n |
\n| Net freshwater intake<\/td>\n | Flow on intake plus conductivity on reused streams<\/td>\n<\/tr>\n |
\n| Freshwater intensity per unit<\/td>\n | Flow on intake plus production meter<\/td>\n<\/tr>\n |
\n| Discharge quality index<\/td>\n | Conductivity, COD, SS, pH on final discharge<\/td>\n<\/tr>\n |
\n| Internal water cost<\/td>\n | Energy meter on treatment, chemical dosing, all of the above<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Shanghai ChiMay’s sensor portfolio covers each of these stacks, and the company’s application engineers help teams map specific sites to specific KPIs.<\/p>\n <\/span>Why Sensor Grade Matters for Reporting<\/span><\/h2>\nA reported water circularity number is only as credible as the measurements behind it. Grab samples once a week are fine for compliance in 2010. In 2026, auditors expect hourly trending, documented calibration, digital diagnostics, and an audit trail from sensor to report.<\/p>\n Key requirements:<\/p>\n |