ZT-620 Automatic Tank Dewatering
Automated removal of free water from storage tanks and vessels
Eliminate Manual Tank Draining
Our automatic tank dewatering systems detect the oil-water interface inside storage tanks and automatically drain accumulated free water. This eliminates the need for manual gauging and valve operations, reduces the risk of oil carry-over, and ensures consistent product quality.
The system pairs two ZT-610 Interface Detectors with a PLC-based control unit and motorised valve to create a fully automated dewatering loop. When the interface probes detect water, the drain valve opens. When oil is detected at the outlet, the valve closes — preventing product loss.
How It Works
Monitor
The watercut sensor is installed on the tank drain line and continuously measures the water content of the fluid passing through.
Detect
When free water accumulates and reaches the drain nozzle level, the sensor detects the transition from oil to water.
Drain
The control unit opens the motorised drain valve, allowing free water to flow to the water treatment system.
Protect
When the sensor detects oil at the drain outlet, the valve closes immediately — preventing oil carry-over and product loss.
Key Features
Fully Automatic
No operator intervention required. The system runs continuously with programmable drain schedules and set points.
Oil Carry-Over Prevention
Real-time watercut sensing at the drain outlet ensures the valve closes before oil enters the water drain system.
Hazardous Area
ATEX and IECEx certified components for installation in Zone 1 and Zone 2 classified areas.
Configurable Set Points
Adjustable water cut thresholds for opening and closing the drain valve. Programmable time delays and drain intervals.
Data Logging
Record drain events, water volumes, and watercut trends for operational analysis and reporting.
Modular Design
System can be retrofitted to existing tanks. Compatible with various valve types and control architectures.
System Specifications
| Interface Sensors | 2x ZT-610 Interface Detector probes |
| Control Unit | PLC-based controller with local display |
| Drain Valve | Motorised ball valve (electric or pneumatic actuation) |
| Drain Line Size | 2" to 6" (custom sizes available) |
| Set Point Range | 0 – 100% water cut (adjustable open/close thresholds) |
| Communication | 4-20mA, Modbus RTU, relay outputs |
| Power Supply | 24V DC or 110/220V AC |
| Hazardous Area | ATEX / IECEx (sensor and valve) |
| Operating Temperature | -20°C to +80°C |
Applications
Crude Oil Storage
Automatic dewatering of crude oil storage tanks at production facilities and export terminals.
Product Terminals
Maintaining product quality in refined product and chemical storage by removing accumulated water.
FPSO & Offshore
Space-constrained offshore applications where manual tank operations are difficult and costly.
Fuel Storage
Aviation fuel and marine fuel storage tanks requiring strict water content limits.
Automate Your Tank Operations
Contact us to discuss your tank dewatering requirements. We can design a system to fit your existing infrastructure and operational needs.
