📍 Project Location: Maharashtra, India — 2×660 MW Coal-Fired Power Plant
💨 Application Scenarios: Wet FGD absorber tower slurry monitoring, gypsum dewatering wastewater, blowdown treatment & final discharge compliance
📅 Implementation: 2024 – present  |  Equipment: GAIMC GWQ-MP200 Multi-parameter Water Quality Analyzer (supports pH/ORP/Conductivity/Turbidity/Residual Chlorine, digital sensors)

Wet Flue Gas Desulfurization (FGD) systems are critical for SO₂ removal in coal-fired power plants. However, maintaining optimal scrubber efficiency requires precise control of slurry pH (typically 5.0–6.0), density (gypsum precipitation), ORP (oxidation conditions), and blowdown water quality. Conventional offline sampling leads to delayed adjustments, scaling, fouling, and non-compliance risks. The GWQ-MP200 multi-parameter analyzer features a high-reliability RTOS and connects digital sensors for pH, ORP, conductivity (density correlation), turbidity, residual chlorine, etc. It enables 24/7 online monitoring of the absorber recirculation loop, gypsum dewatering stream, and blowdown discharge. Data is transmitted via RS485 (Modbus-RTU) and 4-20mA to the plant DCS for automatic lime/limestone feeding, gypsum underflow control, and wastewater treatment, ensuring SO₂ removal efficiency >98% and full compliance with India's environmental norms.

At the Maharashtra 2×660 MW power plant, two GWQ-MP200 analyzers were installed — one on the absorber recirculation loop (pH, ORP, conductivity) and another on the blowdown wastewater line (pH, turbidity, residual chlorine). With continuous online data fed into the DCS for automated lime feeding and underflow control, after 8 months of operation:

• SO₂ removal efficiency increased from 94% to 98.5% (well above India's CPCB standard of 90%);
• Lime/limestone consumption reduced by 22% thanks to precise pH control (±0.1 pH stability);
• Scaling-related downtime decreased by 65% due to density/conductivity-based blowdown optimization;
• Zero environmental non-compliance incidents on blowdown discharge (pH 6–9, turbidity < 30 NTU).

Plant operators reduced manual slurry sampling by 80%, while the integrated data logging provided full traceability for regulatory inspections.

Based on wet FGD process requirements, GWQ-MP200 recommended configuration:

• Absorber tower loop (4 channels): pH + ORP + Conductivity + Temperature — core parameters for SO₂ absorption efficiency and scaling prevention;
• Blowdown / wastewater discharge (3 channels): pH + Turbidity + Residual Chlorine — ensures compliance with local discharge standards (e.g., CPCB norms);
• Optional for gypsum dewatering: additional turbidity channel to monitor filtrate clarity.

When ordering, specify number of channels, parameter type per channel, measurement range, and cable length. Compatible only with digital sensors. Abrasion-resistant electrode options recommended for slurry with high solids content.

“The GWQ-MP200 has transformed our FGD operation. We now maintain slurry pH within a tight ±0.1 range without constant manual checks. The conductivity trend helps us time blowdown perfectly, eliminating unnecessary scaling. Plus, the data logs have made CPCB inspections smooth and credible. A solid investment for any power plant aiming for reliable desulfurization.” — Operations Director, Maharashtra Thermal Power Station