Instrument selection, control philosophy development, loop diagrams, and automation integration for critical water treatment processes systems
CFD, P&ID, SCADA and commissioning for critical water treatment plants.
Plant layouts, piping isometrics and construction-ready engineering drawings.
Flow, mixing and thermal CFD across treatment and process equipment.
Full mechanical, physico-chemical, biological and sludge equipment range.
Proper instrumentation and control design is essential for safe, efficient, and reliable water treatment operation. Our instrumentation and control packages are engineered for each plant.
pH, COD, TSS, ammonia, and flow instruments provide continuous real-time data. 4-20 mA signals feed the PLC for closed-loop control and SCADA trending.
Intuitive operator screens with colour-coded status, trend charts, and alarm summaries. Remote access via secure VPN allows off-site monitoring and support.
Prioritised alarms with SMS and email escalation. Smart suppression prevents flooding. Maintenance reminders based on run-hours and calendar prevent breakdowns.
Daily, weekly, and monthly performance reports generated automatically. Effluent quality summaries, chemical consumption, and compliance status emailed to stakeholders.
Quarterly audits by our engineers verify instrument accuracy, control loop performance, and maintenance practices. Recommendations prevent gradual degradation.
Years of operational data stored securely in the cloud. Export to Excel for regulatory submissions. API access connects to ERP and environmental management systems.
Measurement & Monitoring Devices
System Control Strategy
| Control Type | Description | Example Application |
|---|---|---|
| On/Off Control | Simple two-state control | Pump start/stop, level switches |
| PID Control | Proportional-Integral-Derivative | Flow control, pH control, pressure |
| Cascade Control | Nested control loops | Flow control with level override |
| Ratio Control | Maintain fixed ratio between variables | Chemical dosing proportional to flow |
| Feedforward Control | Anticipatory control based on disturbance | pH adjustment based on influent pH |
How Instrumentation, Control Logic, and SCADA Come Together
Acidic wastewater
Inline probe
PID controller
Variable speed pump
Neutralised effluent
pH is highly non-linear; we use gain-scheduled PID or split-range control to avoid oscillation near the neutral point.
High-high pH trips caustic pump and opens diversion valve. Low-low pH triggers acid pump shutdown and alarm.
Dual pH probes with automatic switchover. Stand-by dosing pump starts on primary pump failure.
Operator sees pH trend, setpoint, pump speed, and totalized caustic consumption on a single loop faceplate.
Level master
Master PID
Slave PID
Discharge line
Constant feed
The level controller adjusts the setpoint of the flow controller. This prevents level swings from disturbing downstream treatment units.
Low-level switch (LSL-501) closes valve on empty-tank risk. High-level alarm (LAH-501) triggers inlet diversion.
Slave loop clamps discharge flow between minimum (to avoid pump dead-head) and maximum (downstream hydraulic capacity).
LT-501 → AI-01, LIC-501 → PID-01, FIC-502 → PID-02, FCV-502 → AO-01, FT-502 → AI-02 on the PLC rack.
| Tag | Description | Type | Signal | PLC Address | SCADA Tag |
|---|---|---|---|---|---|
| FT-101 | Influent flow transmitter | Analogue In | 4-20 mA | %IW64 | DAF_FT_101 |
| LT-201 | DAF tank level transmitter | Analogue In | 4-20 mA | %IW66 | DAF_LT_201 |
| pH-301 | pH analyser | Analogue In | 4-20 mA | %IW68 | DAF_pH_301 |
| P-401A | Recirculation pump A | Digital Out | 24 VDC | %QX0.0 | DAF_P401A_RUN |
| P-401B | Recirculation pump B | Digital Out | 24 VDC | %QX0.1 | DAF_P401B_RUN |
| CV-501 | Sludge discharge control valve | Analogue Out | 4-20 mA | %QW80 | DAF_CV_501 |
| HS-601 | E-stop pushbutton | Digital In | 24 VDC | %IX1.0 | DAF_ESTOP |
Analogue instruments use 4-20 mA. Digital I/O is 24 VDC. Every field tag maps to a unique PLC address and SCADA tag.
E-stop and critical level switches are wired to safety-rated or monitored inputs to ensure fail-safe operation.
Lead/lag alternation between P-401A and P-401B is handled in the PLC with runtime-hour balancing and fault auto-switchover.
Consistent naming conventions (e.g., DAF_ prefix) make it easy to build template displays and alarm sets across multiple units.
Electromagnetic, ultrasonic, vortex, and open-channel flowmeters selected for water and wastewater duty.
Hydrostatic, radar, and ultrasonic level sensors plus pressure transmitters for tanks and pipelines.
pH, ORP, conductivity, turbidity, dissolved oxygen, and chlorine analysers for real-time quality monitoring.
Control valves, variable-frequency drives, dampers, and chemical dosing pumps for precise actuation.
Proportional-integral-derivative loops for flow, pH, pressure, and level regulation.
Nested loops such as flow control with level override for tank discharge management.
Chemical dosing proportional to influent flow and anticipatory pH correction.
Pump start/stop logic, filter backwash sequences, and blower duty cycling.
Seamless connection to supervisory control platforms with standardised communication protocols.
Custom MCC and control panel specifications with clear wiring and termination diagrams.
Detailed input/output registers mapping every signal to PLC addresses and SCADA tags.
Systematic loop testing and calibration to ensure every control element performs as designed.
tagging compliant
loops designed
integration ready
commissioning issues
P&ID development for advanced biological treatment systems: activated sludge, SBR sequencing, MBBR media retention, anaerobic.
View PageP&ID development for DAF and flotation systems: saturator pressure control, air dissolution loops, recycle pumps, flotation cell.
View PageIndustry-standard flow diagrams for critical water treatment processes engineering.
View PageHAZOP and process hazard analysis for critical water treatment processes plants.
View PageProcess flow diagram development for critical water treatment processes systems.
View PageOur engineers can develop comprehensive control philosophies and instrumentation specifications for your water treatment system.
Our expertise spans multiple industries with sector-specific water treatment solutions.