GreenPrima ProLev800 Ultrasonic Sludge Interface Level Gauge

Overview

The GreenPrima ProLev800 is a high-reliability ultrasonic sludge interface level gauge engineered for continuous, non-contact measurement of the sludge-liquid interface in wastewater and industrial sedimentation basins. It operates on the time-of-flight principle: an ultrasonic pulse is transmitted downward from a submersible transducer mounted above the liquid surface; the time interval between emission and reception of the reflected echo from the sludge layer boundary is precisely measured and converted into distance using the speed of sound in the medium. This method enables accurate determination of both sludge blanket height and thickness—critical parameters for optimizing clarifier hydraulics, managing return activated sludge (RAS) flow, and detecting early-stage settling anomalies such as bulking or rising sludge. Designed specifically for demanding municipal and industrial applications—including primary and secondary clarifiers, gravity thickeners, pre-concentration tanks, and coal washery tailings ponds—the ProLev800 delivers stable performance under variable solids concentrations, temperature gradients, and surface turbulence.

Key Features

• Large backlit LCD display supporting simultaneous numeric depth readout, real-time echo waveform visualization, and dynamic trend plotting (5 minutes to 48 hours)
• Embedded microprocessor architecture enabling adaptive signal filtering, automatic gain control, and robust echo discrimination—even under low-reflectivity or multi-layer sludge conditions
• Interface tracking algorithm optimized for gradual and abrupt sludge level transitions, with no moving parts or mechanical wear components
• Configurable dual-transducer support: a single transmitter unit can drive and process data from two independently mounted ultrasonic sensors—reducing hardware footprint and system integration cost
• User-friendly local configuration via intuitive menu navigation; adjustable screen brightness for varying ambient lighting conditions
• Two programmable relay outputs for high/low level alarms, compatible with SCADA and PLC-based supervisory systems
• IP68-rated housing for full submersion capability and long-term operation in aggressive chemical environments (e.g., chlorinated or sulfide-rich wastewater)

Sample Compatibility & Compliance

The ProLev800 is validated for use across diverse sludge matrices including activated sludge, anaerobic digester supernatant, primary settleable solids, and fly ash slurries encountered in power generation facilities. Its ultrasonic sensing modality remains unaffected by conductivity, turbidity, color, or suspended solids concentration—making it suitable for applications where optical or capacitance-based methods fail. The instrument complies with IEC 61326-1 (EMC for industrial environments) and IEC 61000-6-2/6-4. While not intrinsically safe certified, optional ATEX-compliant variants are available upon request for Zone 2 hazardous locations. Data logging and alarm event records align with GLP/GMP documentation requirements when integrated with compliant SCADA platforms supporting audit trail functionality per FDA 21 CFR Part 11.

Software & Data Management

Local operation requires no external software; all configuration and diagnostics are performed directly via the front-panel interface. For remote monitoring and historical analysis, the RS232 serial port supports ASCII protocol communication with third-party HMI or historian systems (e.g., Ignition, Siemens Desigo, or OSIsoft PI). Raw echo amplitude profiles and timestamped level values can be exported for post-processing in MATLAB or Python-based settling velocity analysis tools. Firmware updates are delivered via secure USB stick—ensuring traceability and version control during plant-wide deployments.

Applications

• Municipal wastewater treatment plants: RAS optimization in secondary clarifiers, thickener feed control, and early detection of septicity-induced sludge rise
• Coal preparation plants: Monitoring of densimetric separation layers in spiral concentrators and tailings thickeners
• Thermal power stations: Interface level surveillance in ash slurry settling ponds and bottom ash handling systems
• Industrial effluent treatment: Control of lamella clarifier underflow density and flotation scum layer thickness
• Drinking water production: Detection of floc blanket collapse in upflow clarifiers and pulse-type settlers

FAQ

Can the ProLev800 distinguish between multiple sludge layers (e.g., light and heavy fractions)?
Yes—the instrument captures full echo amplitude vs. time profiles, allowing trained operators or custom post-processing algorithms to identify secondary reflection peaks corresponding to internal density gradients.
Is calibration required after installation?
No field calibration is needed; factory calibration is traceable to NPL (UK) standards. Zero offset verification can be performed using a known reference distance during commissioning.
What maintenance intervals are recommended?
Transducer face cleaning every 3–6 months depending on solids loading; no scheduled internal servicing is required due to solid-state design and absence of consumables.
Does it support Modbus RTU or other industrial protocols?
Standard RS232 ASCII output is provided; optional Modbus RTU or HART-enabled versions are available under OEM agreement.
How does it perform in foaming or scum-covered tanks?
Foam attenuates ultrasonic energy; for reliable interface detection in such conditions, GreenPrima recommends pairing the ProLev800 with a guided-wave radar (GWR) sensor for cross-verification—supported via dual-input firmware mode.