STP automation
PLC control of pumps, blowers and dosing, SCADA screens, and the plant's compliance data in the same place
A sewage treatment plant runs on a few decisions made all day: when to run which pump, how hard to run the blowers, how much to dose. We automate those decisions with a PLC, show the plant on SCADA screens, and connect the whole to OCEMS, so the plant's operation and its compliance data are seen in one place.
We also retrofit existing plants that were built with manual starters, and operate and maintain what we automate. Our current work includes the automation of the 6 MLD STP at Model Town, Ambala City, for PHED Haryana, with PLC SCADA, flow meters, data loggers and a cloud dashboard.
- PLC
- SCADA
- DO-based blower control
- SYZE-DO 485
- OCEMS integration
- Retrofits
- O&M
What we automate
- Pumps
- Inlet, intermediate and sludge pumps on level and time, with duty rotation, dry-run protection and run-hour logging.
- Blowers on dissolved oxygen
- The PLC reads the SYZE-DO 485 in the aeration tank and modulates the blowers to hold a DO set point, so they run as hard as the biology needs and no harder.
- Dosing
- Chlorine, coagulant or polymer dosing on flow, with alarms when a tank runs low.
- Interlocks and alarms
- Trips, overloads, high and low levels and failed starts raised as alarms on the SCADA and by SMS or email.
- SCADA screens
- The plant drawn as it is built, with live values, trends, alarm lists and run-hour and energy reports, on a local screen and remotely.
- Operator control
- Auto, manual and remote modes for every drive, with user roles and a log of who changed what.
Joined to OCEMS
- One picture of the plant
- Flow, COD, BOD, TSS, pH and DO from the OCEMS instruments next to the state of every pump and blower, on the same dashboard.
- Compliance and operation together
- When an outlet reading rises, the operator sees what the plant was doing at the time; when a blower trips, the effect on the outlet is visible.
- The same data logger
- The SYZE data logger reads the PLC over Modbus as it reads the analysers, so the boards, PHED and the plant's own staff see data from one source.
- Reports for the department
- Daily and monthly reports of flow, treated quality, run hours and energy, in the formats PHED divisions ask for.
Retrofitting an existing plant
Survey
We record the drives, starters, instruments and panels on site, and what the operators do by hand today.
Design
A control philosophy agreed with the plant: what runs on what, set points, interlocks and alarms.
Panel and instruments
The PLC panel built and installed, with the DO meter, level and flow instruments the control needs.
SCADA and OCEMS
Screens built, the PLC connected to the SYZE data logger and the plant shown on the OCEMS dashboard.
Commissioning and training
Loops tuned on the running plant and the operators trained on the screens and the modes.
Operation and maintenance
Our team operates and maintains the automation and the monitoring under one contract where the plant wants it.
Questions about STP automation
Can an existing STP be automated without stopping it?
Usually yes. The new panel is built alongside the old starters and drives are moved over one at a time, with the plant running.
Why control the blowers on DO?
Blowers are the largest power load at most STPs. Holding a DO set point instead of running them continuously keeps the biology healthy and saves energy.
Does the automation report to the boards?
The outlet readings go to CPCB, HSPCB or PPCB through the same data logger, as in any of our OCEMS installations. The plant's operating data stays with the plant and PHED.
Do you operate the plant as well?
We operate and maintain the automation and the monitoring; the treatment process itself is operated with the plant's staff or its O&M contractor, as the contract sets out.
Related
- SYZE-DO 485 dissolved oxygen meterMade by SYZE: optical DO, 0.1–20.0 mg/L, RS-485 Modbus RTU
- Online water quality analyser (8 parameters)Our main product: eight parameters as standard, made in India
- OCEMS data loggerMade by SYZE (OEM) for CPCB, HSPCB and PPCB connectivity
- STP online monitoringOutlet effluent quality, inlet and outlet flow, and data to CPCB, HSPCB and PHED
- OCEMS in Haryana (HSPCB)Online continuous effluent monitoring for STPs, ETPs and industries, connected to HSPCB, CPCB and PHED
- O&M, AMC and calibrationKeeping a station accurate, connected and accepted by the boards, year after year
See it working
Send us the plant's drive list and a single-line diagram, and we will propose the automation.