Suspended Solids Monitor in India: How to Choose the Right Online Sensor

Suspended Solids Monitor in India: How to Choose the Right Online Sensor

Selection of suspended solids monitor in India is not something which can be done only on paper using data sheets. It is always the load fluctuations during monsoon, the sticky nature of sludge, algae coating of optic lenses and non-stop plant operations which will determine whether an instrument will find its right place or become the regular cleaning job for the operator. The following article gives tips about how to select the right instrument for monitoring suspended solids.

Quick answer: The best suspended solids monitor for India will be the one which uses the right measurement method, has the right range and proper self-cleaning system. Most often this will mean optical suspended solids monitor with automatic wiper and Modbus RS-485 output.

What Is a Suspended Solids Monitor?

The suspended solids monitor is an on-line meter that quantifies total suspended solids (TSS) – particles that are suspended in water rather than dissolved in it. This measurement is given in mg/l immediately, without requiring a laboratory test. In most meters, there is a light beam shone into the sample and measuring its absorption/scattering capacity.

TSS must not be confused with turbidity. Turbidity is a qualitative measurement of the cloudiness of water whereas TSS is a quantitative measurement of suspended solids in it. Although there is some correlation between turbidity and TSS, they are not the same and thus Suspended Solids Monitor in India should be calibrated to your samples.

Why Industries Require a Suspended Solids Monitor in India

There are three main reasons:

• Compliance – TSS is a required effluent parameter. In India, the suspended solids monitor typically operates with COD and pH alongside in OCEMS style continuous monitoring. Refer to your own consent for the precise figures.
• Process control – Process variables such as sludge concentration, clarifier efficiency and backwash of filters rely on information about solids.
• Cost savings – Early detection of clarifier upset minutes after rather than hours or days after means reduced consumption of chemicals, energy and possible fines.

How to Choose a Suspended Solids Monitor in India: Six Checks

1. Measuring principle

The backscatter sensors usually apply for low to medium solids content, whereas the near-infrared absorption applies to high sludge concentration. The BH512-A uses the backscattering method at 135°. The BH518-A uses the near-infrared absorption method.

2. Range and accuracy

Select range according to the maximum reading, not the average value. The BH512-A range is from 0.5 to 4,000 mg/L, with an accuracy of 0.1 mg/L at ±5%, suitable for treated effluent and process water of moderate load. The BH518-A range is from 0 to 10,000 mg/L, at ±5% or ±20 mg/L (whichever is greater), appropriate for thick sludge.

3. Self-cleaning

Fouling is the number one source of drift. Biofilm, oil and air bubbles on the optical window are treated by the sensor as solids. For a suspended solids monitor in India that operates during humid and algal seasons, an automatic cleaning wiper is a must.

4. Installation and materials

Both products feature IP68 housing. BH512-A is certified to be submerged to the depth of 10 m and features POM body. BH518-A can be used up to 30 m depth with POM and SS316 (Ti) bodies. If you consider to use a bypass line, then a flow-through model such as BH7950D could be used.

5. Output and power

Both sensors are based on Modbus RS-485 protocol. Both the BH512-A sensor operates at DC 5-12V and the BH518-A sensor at DC 12-24V and consumes less than 50mA at normal operation and less than 200mA during cleaning. Check compatibility with your PLC or datalogger to ensure Modbus support prior to purchase.

6. Calibration and support

Find out how calibration takes place on-site, what a replacement wiper costs and whom you will contact when something goes wrong. Service usually plays a greater role than the last decimal of accuracy.

Which Sensor Fits Which Application?

Below is an application map of the suspended solids monitoring sensor in India:

 

Application	What you need	Option
Treated effluent discharge	Low–mid range, fine resolution	BH512-A
Aeration tank, thick sludge	Range up to 10,000 mg/L	BH518-A
Sampling or bypass line	Flow-through mounting	BH7950D
Sludge concentration	Digital sludge sensor	BH7850D

Common Mistakes to Avoid

• Range only buying – Excessive range defeats resolution when you have 30 mg/L of water.
• Cleaning not being done – The sensor will report its own fouling in that case.
• Site calibration neglected – Particle size and colour affect measurement.
• Wrong positioning – Suspended solids monitor in India positioned in a dead zone will accurately report a dead zone, not your process.

Conclusion

The perfect Suspended Solids Monitor in India is that which fits your specific water: its principle, range, cleaning and output. Begin with the maximum possible solids level, narrow it down to two sensors and check them using grab samples.

Need a second opinion? Check out the entire TSS/Turbidity sensor line up, or get in touch with Fluidings’ team at +91 8928335585 or info@fluidings.com for a quote/consultation.

FAQS

1. What is a suspended solids monitor used for?

A suspended solids monitor measures the amount of undissolved particles in water in mg/L. The industries use this instrument to measure effluent quality, control sludge in aeration tanks, and monitor clarifiers operation without laboratory tests results.

2. What is the difference between TSS and turbidity?

Turbidity measures water light scattering ability and is presented in NTU, whereas TSS measures the actual amount of solids per litre and is presented in mg/L. These two measurements are correlated with each other, however, this correlation depends on particle size and colour, thus site calibration is required.

3. How to select Suspended Solids Monitor in India for wastewater?

Choose the sensor that meets your peak solids load, its measuring principle and range. Also, check that the sensor has automatic cleaning system, IP68 protection level, Modbus RS-485 output and calibration function. The low-range effluent and thick sludge require different sensors.

4. Is it necessary to clean the suspended solids probe?

Yes, but much less frequent if it uses automatic wiper. Biofilm formation, grease, and bubbles of air on the optical window cause drift, so wiper removes them according to the schedule. Inspection from time to time and recalibration using grab samples is also good to do.

5. Can I use my TSS sensor with PLC or SCADA system?

Yes. Fluidings’ suspended solids sensors such as BH512-A and BH518-A can output Modbus RS-485 signals that can be read by most of PLCs, data loggers, and SCADA systems. Make sure you use correct power supply, 5–12 V or 12–24 V DC.