Sludge Blanket Level Detectors use ultrasonic technology, so they are also known as ultrasonic mud level meters.

Ultrasonic Sludge Blanket Level Detector uses ultrasonic emission with echo analysis of solids suspended in water. The height and thickness of the sludge layer can be accurately measured. Effective grasp of sludge settling characteristics. The control of sludge return flow rate.

Ultrasonic sludge interface meter/mud level meter supports various variable outputs. Such as 4-20mA variable output, relay high and low alarm control output, and RS485 communication output.

Automatic monitoring and control of sludge level can be achieved by setting the Ultrasonic Sludge level sensor.

Automatic Sludge Blanket Level Detector

What is sludge blanket level?

Sludge (sludge) is a solid settling material produced by water and wastewater treatment processes. The sludge blanket level is the interface between the settled sludge and the turbid or clear water phase above. The sludge level can be the distance from the water surface (sludge level depth) or the distance from the bottom of the tank (sludge level height).

Due to the highly variable nature of all types of sludge, classification is essential, and its treatment and disposal are different. According to its origin, it can be classified as

  • Municipal sludge (civil sludge, also called drainage cement sewage sludge,). It mainly refers to sludge from sewage plants, which is the largest category of sludge in terms of quantity. In addition, sludge from waterworks can also be included in this category.
  • Pipe network sludge, sludge from drainage collection systems.
  • River and lake sludge, sludge from rivers and lakes.
  • Industrial sludge, from a mixture of solids and water, oil, chemical pollution, and organic matter produced by various industrial production.

In (waste) water treatment and process control, sludge water level is an important parameter. Especially in the process of phase separation, accurate sludge level information is crucial. Automatic Sludge Blanket Level Detector can be installed in clear, turbid or even heavily contaminated media with high concentration of suspended matter.

The treatment of many wastewater effluents requires the separation of solids and liquids by sedimentation. The sedimentation process is usually done in a settling tank or a special thickening tank. A sludge interface meter is used to monitor the sludge level in the tank and control the discharge cycle of the settling tank or thickening tank. When the sludge interface meter detects that the sludge has reached the design level, it can control the sludge discharge pump for sludge discharge.

Technical Parameter

CategoryBasic parameters
FunctionSplit type ultrasonic mud level meter
Range5m, 10m, 15m, 20m, 30m, 40m, 50m, 60m, 70m
Measurement Accuracy1%-2%
Resolution5mm or 0.5%
DisplayLCD display
Analog Output4~20mA/7500 load
Relay OutputSingle channel for 2 groups of AC250V/8A or DC30V/5A status programmable
Power supplyStandard 220VAC+15%50Hz optional 24VDC120mA custom 12VDC or battery power
Ambient TemperatureDisplay meter (transmitter) -20~+60℃, probe (sensor) -20~+80℃
CommunicationOptional 485,232 communication (factory protocol)
Protection levelDisplay meter IP65,Probe IP68
Probe CableUp to 100m, 10m standard
Probe installationAccording to the range and probe selection
Product power consumptionWith 24V power supply, the power consumption without relay is 100mA, with a relay is to 120mA,
2 way relay 145mA, 3 way relay to 170mA, 4 way relay to 190mA.
Specific power as follows.
No relay is 24 × 100mA = 2.4W;
1 way relay is 24×120mA=2.9W;
2-way relay is 24×145mA=3.5W;
3-way relay is 24×170mA=4.1W;
2-way relay is 24×190mA=4.6W;

portable sludge blanket level detector, is specially designed for sedimentation tank sludge interface measurement and instrumentation. The meter adopts the innovative multi-beam mutual compensation technology to measure the concentration of suspended matter. A high precision pressure sensor is also used to measure the water depth. It can simultaneously measure and display the suspended matter concentration and water depth at the sensor location.

portable sludge blanket level detector

The operator can easily determine the distribution of the sludge interface in the settling tank based on the sludge concentration value and the water depth. It is especially suitable for the inspection and measurement of sludge concentration and interface of sedimentation tanks in wastewater treatment plants and feedwater treatment plants.

The instrument is ergonomically designed, easy to carry and easy to operate. The rechargeable battery power supply can automatically record the measurement data, which is very convenient for the operator.

Technical Parameter

Measurement range.Concentration 0~50000mg/l, water depth 0~10m
Resolution.Concentration 1mg/l, water depth 0.01m
Accuracy.Concentration ±1%FS, water depth ±0.5%FS
Calibration.Factory calibration, field calibration available
Display.LCD display of date and time, measured value, historical trend line, etc.
Digital interface.USB
Data storage. 64M Flash
Operation settings: Completed via transmitter keypad
Power supply method.Battery powered with charger
Battery life.Each charge can measure about 1000 minutes, with power indication
Size.228×117×86, Φ45×130
Material.Controller PC, sensor stainless steel
Transmitter weight.0.5Kg
Sensor weight.0.5Kg
Sensor Cable.Shielded cable 10m, (other lengths can be specified in the order)
Operating Temperature. Controller -10~55℃, sensor 0~60℃
Relative Humidity.0~100%
Operating pressure.7.5Bar

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Sludge Blanket Level Detector Appliactions

  • Waste treatment clarifiers.
  • Primary sedimentation tanks, secondary sedimentation tanks, gravity sedimentation tanks.
  • Petroleum/asphalt separation tanks.
  • Paper pulp tanks.
  • Beverage water clarifiers.
  • Mining clarifiers.
  • Brine tanks.
  • Slurry tanks.
  • Any vessel in which a liquid/solid two-phase interface exists.

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Sludge Blanket Level Measurement Cases

Sludge Blanket Level Measurement Cases 1

Project Background

  1. a combined double chamber (aeration/sedimentation tank) tank.
  2. diameter of the combined tank 10m.
  3. a depth of 3,200mm.
  4. There is no available communication line nearby.

Measurement requirements

  1. measurement and control of the sludge layer height in the secondary sedimentation tank.
  2. automatic control of the sludge level directly through the transmitter.
  3. Wireless transmission of the analog output signal to the control system.


  1. using a sludge interface meter.
  2. the transmitter activates the sludge discharge step when the sludge exceeds 160 cm or falls below 120 cm
  3. installation on the existing scraper beam.
  4. the measurement data is transmitted via a separate radio line because there are no redundant communication lines.


  1. Simple and fast installation without welding.
  2. analog signals can be transmitted to the process control system via a radio connection.

Sludge interface measurement in sludge pre-thickener

Application scenarios

1、DN 15,000mm sludge pre-thickening tank.
2、Depth 9,500mm.
3、Volume about 1,500 m.

Measurement tasks

Replacement of a faulty existing sludge interface meter, which cannot change the existing structure.
Suspension of the new sensor over the existing top opening and insertion of the sensor into the medium to be measured.
Conversion of the sludge interface height to a 4-20 mA signal via the existing wiring to the existing control system.


  1. use of a sludge interface meter.
  2. Install the transmitter in the pre-thickener and suspend the sensor in the medium via a chain from the existing top opening.


  1. easy and fast retrofit without structural changes.
  2. Explosion-proof and waterproof.

Measurement of sludge interface height in multiple secondary sedimentation tanks

Project Background

  1. multiple secondary sedimentation tanks in a wastewater treatment plant.
  2. Size of Ø18m.

Measurement tasks

  1. measurement of the sludge interface height in the secondary sedimentation tanks.
  2. feedback control of sludge discharge and water intake.
  3. Provide 4-20mA signal for SCADA system.


  1. selection of sludge interface meter for sludge interface measurement.
  2. sensor: VT sensor.
  3. Settled sludge below the threshold (yellow) will not be accepted, so that the sludge deposition at the bottom can be well evaluated. Advantages
  4. easy to install.
  5. simple maintenance.
  6. High measurement accuracy.

Sludge interface meter to measure slurry height of thickener

The thickener generally separates the solid from the liquid, and below is the settled slurry. The thickness of these well settled slurry is measured with a sludge interface meter.

These settled slurries are available for secondary use. So it is necessary to remind the operator to discharge the slurry after reaching a certain height. Such working conditions are very suitable for sludge interface meter application.

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More Featured Ultrasonic Level Meters


Ultrasonic sludge interface meter is using the reliable ultrasonic echo detection principle to calculate the ultrasonic wave return to the probe The height and thickness of the sludge layer can be calculated by calculating the time of the ultrasonic wave returning to the probe. Effectively grasp the sludge sedimentation characteristics and The ultrasonic mud-water interface meter uses the principle of reliable ultrasonic echo detection to calculate the height and thickness of the sludge layer.

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The Automatic Sludge Blanket Level Detector supports local display. It also supports variable outputs such as 4-20mA variable output, relay high and low alarm control output and RS485 communication output.

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Sino-Inst is Manufacturer of Automatic Sludge Blanket Level Detector. We supply more than 20 kinds of Ultrasonic Level Sensors. 40% ultrasonic level meters, 40% External Ultrasonic Liquid Level Meters and 20% Automatic Sludge Blanket Level Detectors.

Automatic Sludge Blanket Level Detector reference wholesale price USD 755.00/set

Automatic Sludge Blanket Level Detector is commonly used for sludge interface measurement in primary and secondary settling tanks, sludge thickening tanks in wastewater treatment. And sedimentation tank level measurement in water treatment plants.

It is also widely used in industries that require solid-liquid separation in production processes such as paper, mining, power, and petroleum. Monitoring the height of solids in the sedimentation process. For example, oil/asphalt separation tank, paper pulp tank, power mortar sedimentation tank, mining clarification tank, etc.

Automatic Sludge Blanket Level Detectors enable stable level measurement without tank modifications. This greatly meets the measurement needs of many applications. Can be used from small to large tanks.

Sino-Inst’s Automatic Sludge Blanket Level Detectors, made in China, Having good Quality, With better price. Our level measurement instruments are widely used in China, India, Pakistan, the US, and other countries.

The entire team at Sino-Inst’s has received excellent training, so we can ensure that every client’s needs are met. For assistance with your product requirements, whether it’s a Automatic Sludge Blanket Level Detector, flow sensor, or other device, give us a call.

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