Measurement of Fluoride in Industrial Wastewater
Industries such as glass manufacturing, aluminum (metal) smelting, semiconductor production, and fertilizer processing generate wastewater with high fluoride concentrations, posing significant environmental and health risks.1
Accurate measurement2 and management of fluoride levels is crucial for regulatory compliance and environmental protection.
LAQUAtwin F-11 fluoride ion meter provides a reliable, on-site solution for fluoride monitoring, enabling industries to effectively manage and reduce fluoride discharge.
Introduction
Fluoride contamination in industrial wastewater is a significant environmental issue. Industries such as glass manufacturing, aluminium smelting, semiconductor production, and fertilizer processing generate wastewater with high fluoride concentrations. Fluoride, used in these industries can lead to effluents3 containing harmful levels of fluoride if not properly managed.
Excessive fluoride in the environment can cause severe health issues4, including dental and skeletal fluorosis which results in tooth discoloration, enamel damage, and bone deformities. High fluoride exposure may also affect the urinary, renal, endocrine, brain, and reproductive systems.
To meet regulatory standards and mitigate these risks, industries use treatment methods such as adsorption using activated alumina or bone char, membrane processes like reverse osmosis and nanofiltration, chemical precipitation with calcium salts, and electrocoagulation.
Accurate measurement and management of fluoride levels are essential to ensure compliance with environmental regulations and for the protection of public health.
The LAQUAtwin F-11 fluoride ion meter offers a convenient and reliable solution for on-site fluoride measurement, enabling industries to monitor and manage fluoride levels effectively. The meter analyses as little as 0.3ml sample and delivers accurate result in seconds. This rapid test enables industries to adjust their wastewater treatment systems promptly, ensuring compliance with local regulatory discharge limits.
Many countries have stringent environmental regulations that require the industries to ensure that the fluoride concentration in their discharge does not exceed specific limits. Exceeding these limits can result in significant fines and environmental repercussions.
Refer to Table 3 for Fluoride Effluent Limit of Some Countries.
Table 1: Industries with High Fluoride Wastewater
| Industry | Description |
|---|---|
| Glass Manufacturing | Industry uses fluorinated compound (AlF3) to help improve properties of glass, introducing fluoride into wastewater during production processes.5 |
| Aluminium Production | Fluoride is used in the form of cryolite (NaFAlF3) in the electrolytic reduction of alumina to aluminium6, leading to significant fluoride emissions in wastewater. |
| Fertilizer Plants | Phosphate fertilizers contain fluoride7, which can leach into wastewater during production and application. |
| Semiconductor Etching | Etching process use fluoride-containing chemicals8 (HF) to create intricate patterns on silicon wafers. Process generates wastewater with high fluoride concentrations. |
Table 29: Methods for Fluoride Removal
| Method | Description |
|---|---|
| Adsorption |
Activated Alumina is used to adsorb fluoride ions in water. Bone Charcoal: Charred animal bones are used as catalyst to adsorb fluoride. |
| Membrane Processes |
Reverse Osmosis (RO): The membranes effectively remove ions from wastewater by forcing water through a semi-permeable membrane, leaving fluoride ions behind. Nanofiltration: Similar to RO, nanofiltration membranes can selectively remove fluoride ions from water. |
| Chemical Precipitation | Calcium Salts: Adding calcium salts (calcium chloride) to wastewater can precipitate fluoride as calcium fluoride (CaF2), which can then be removed by sedimentation or filtration. |
| Electrocoagulation | Electrical current is used to coagulate and remove fluoride from wastewater. |
Method
Sample Preparation
Collect a minimum sample (1 ml) of the effluent in the 5ml plastic beaker. Refer to the table below.
| Type of Sample | Does the sample contain Fe3+, Al3+, Si4+ or highly concentrated ions? | |
|---|---|---|
| Yes | No | |
| Two-Point Calibration |
|
Calibrate with 1ppm and 10ppm standard solutions. |
| Measurement | Add 1mL of TISAB & 1mL of sample and measure. | Measure sample directly. |
Calibration
Calibrate the meter with the 1ppm and 10ppm standard solutions provided to ensure accuracy.
Measurement
Place a few drops of the sample on the sensor and wait for a stabilized reading, which will be indicated by ☺.
Recording Results
Record the measurement for compliance and reporting purposes.
Results and Benefits
Using the LAQUAtwin F-11 fluoride ion meter provides several benefits:
- Immediate Results: Obtain fluoride concentration readings onsite without delays, enabling prompt decision-making.
- Compliance Assurance: Ensure that effluent discharge meets regulatory standards, avoiding fines and environmental penalties.
- Portability: The compact and portable design of the meter allows easy on-site testing, making it convenient for use in various locations within the facility.
By implementing the LAQUAtwin F-11 fluoride ion meter, companies can efficiently manage their fluoride discharge, ensuring compliance with environmental standards and avoiding potential fines.
Table 3: Fluoride Effluent Limit of Some Countries
| Country | Fluoride Effluent Limit (ppm / mg/L) |
|---|---|
| Singapore | 15.010 |
| Malaysia |
2.0 (Standard A*), 5.0 (Standard B**)11 *Any inland waters within catchment areas. **Any other inland waters or Malaysian waters. |
| India | Fluoride in effluent is 2.0 mg/L for inland surface water and 15 mg/L for marine coastal areas12 |
Standard A: This standard applies to the discharge of effluents into any inland waters within catchment areas. The limits are stricter to protect sensitive water bodies and ecosystems.
Standard B: This standard applies to the discharge of effluents into any other inland waters or Malaysian waters. The limits are less stringent compared to Standard A.
References and Suggested Readings
- Ahmad, S., Singh, R., Arfin, T., & Neeti, K. (2022, September 28). Fluoride contamination, consequences and removal techniques in water: A Review. Environmental Science: Advances. Retrieved from https://pubs.rsc.org/en/content/articlelanding/2022/va/d1va00039j
- Khatkar, R., & Nagpal, S. (2023, January 24). Conventional and advanced detection approaches of fluoride in water: A review - environmental monitoring and assessment. SpringerLink. Retrieved from https://link.springer.com/article/10.1007/s10661-022-10888-x#Fig1
- Sinharoy, A., & Chung, C. M. Fluoride removal from wastewater and potential for resource recovery: Comparative studies between different treatment technologies. Environmental Engineering Research. Retrieved from https://www.eeer.org/journal/view.php?number=1574
- Tao, W., Huo, Q., Li, Y., Gu, J., Nie, Y., Li, J., Liu, H., Sawangjang, B., Abdul-Wahab, S., Dong, L., Wang, C., … Xiangyang, M. (2024, August 12). Evaluation of fluoride emissions and pollution from an electrolytic aluminum plant located in Yunnan Province. Journal of Hazardous Materials. Retrieved from https://www.sciencedirect.com/science/article/abs/pii/S030438942402079X
- Diwani, G. E., Amin, Sh. K., Attia, N. K., & Hawash, S.I. (2022a, May 18). Fluoride pollutants removal from industrial wastewater - bulletin of the National Research Centre. SpringerOpen. Retrieved from https://bnrc.springeropen.com/articles/10.1186/s42269-022-00833-w
- Sinharoy, A., & Chung, C. M. Fluoride removal from wastewater and potential for resource recovery: Comparative studies between different treatment technologies. Environmental Engineering Research. Retrieved from https://www.eeer.org/journal/view.php?number=1574
- Ahmad, S., Singh, R., Arfin, T., & Neeti, K. (2022, September 28). Fluoride contamination, consequences and removal techniques in water: A Review. Environmental Science: Advances. Retrieved from https://pubs.rsc.org/en/content/articlelanding/2022/va/d1va00039j
- Yadav, M., Singh, G., & Jadeja, R. N. (2021). Fluoride contamination in groundwater, impacts, and their potential remediation techniques. Groundwater Geochemistry, 22–41. Retrieved from https://doi.org/10.1002/9781119709732.ch2
- Ahmad, S., Singh, R., Arfin, T., & Neeti, K. (2022, September 28). Fluoride contamination, consequences and removal techniques in water: A Review. Environmental Science: Advances. Retrieved from https://pubs.rsc.org/en/content/articlelanding/2022/va/d1va00039j
- Attorney-General's Chambers. (2024). Sewerage and Drainage (Trade Effluent) Regulations. Singapore Statutes Online. Retrieved from https://sso.agc.gov.sg/SL/SDA1999-RG5?DocDate=20240328&ProvIds=Sc2-&ViewType=Advance&Phrase=Fluoride&WiAl=1
- Retrieved from https://compliance.com.my/wp-content/uploads/2017/08/EQA-Industrial-Effluent-2009-5th-Schedule.pdf
- Retrieved from https://www.mpcb.gov.in/sites/default/files/common-effluent-treatment-plant/guidelines/CETP%20Standards.pdf
LAQUAtwin: the only meters with flat sensor technology.
HORIBA’s highly-sensitive, flat sensor technology opens up new possibilities for sampling and sample types. Only a small amount of sample is required, so you can easily sample in situ without the need for beakers or other labware. Sensors are easily replaced as required.
Calibrate and measure at the touch of a button — the smiley face will tell you when the result can be read.
LAQUAtwin is fully waterproof and dustproof.
The meter and sensor are fully waterproof* and dustproof, so you can take it anywhere.
* IP67 rated. Will withstand immersion for 30 minutes at 1 m. Not suitable for underwater use.
Carry case comes as standard for handy portability.
The compact carry case contains everything you need for your measurements, including the standard solution and sampling sheets.
Matching products
Horiba LAQUAtwin Fluoride Ion Tester for Mobile Water Analysis Mobile fluoride hand tester with ion-selective electrode for fast and reliable on-site measurements The Horiba LAQUAtwin Fluoride Ion Tester was specifically designed to measure fluoride concentrations in various samples. Using its ion-selective measurement principle, it can detect fluoride in very small sample volumes (from 0.3 ml or 0.1 ml with sampling sheet) and covers a wide measurement range from 0.1 to 990 ppm. This makes the device versatile, suitable for applications from drinking water analysis to industrial processes. Mobile Fluoride Ion Tester for Precise Water and Environmental Analysis Equipped with a fluoride-selective electrode, the tester provides high measurement accuracy of ±2% of the reading. Automatic two-point calibration (1 ppm and 10 ppm) ensures reliable results. Additional features like Auto-Hold and Auto-Stable support accurate reading of stable values in the field. The IP67 waterproof housing protects the device from moisture and dust. A replacement sensor is also available to ensure long-term use of your Horiba LAQUAtwin Fluoride Ion Tester. Why Fluoride Measurement Is Important – Horiba Hand Tester as an Ideal Solution Fluoride content is a critical parameter in drinking water monitoring, environmental analysis, and in medical and industrial applications. Both excessively high and low fluoride concentrations can have health, ecological, or regulatory impacts, making regular monitoring essential. A mobile fluoride hand tester allows rapid on-site analysis without time-consuming laboratory testing. The robust IP67-protected design, replaceable sensor, and easy operation make the Horiba LAQUAtwin Fluoride Tester an ideal solution for routine checks, field measurements, and quality control. Applications of the Horiba Fluoride Pocket Tester Health and Dentistry: Experts use the F-11 to monitor fluoride levels in drinking water, a crucial measure to prevent dental diseases and promote oral health. Water Quality Monitoring: Environmental technicians use the tester to check fluoride concentrations in drinking water, wastewater, and natural bodies of water, ensuring compliance with environmental standards and safety regulations. Industrial Applications: To meet occupational and environmental safety standards, the F-11 allows rapid testing of process and wastewater in industries where fluoride compounds are used or produced. Environmental Analysis: The pocket tester delivers precise data for studying the effects of fluoride on biological systems, particularly where water quality monitoring and regulatory compliance are required.
The HORIBA LAQUAtwin Pocket Testers provide a comprehensive solution for immediate and precise measurement of water quality parameters directly in the field. To ensure that these measurements remain reliable and accurate, it is essential to regularly check the sensors and replace them with spare sensors if necessary. The replacement sensors, developed specifically for the HORIBA LAQUAtwin series, cover a variety of types for different measurements: pH, conductivity, salinity, redox (ORP), as well as ion-selective sensors for sodium, potassium, nitrate, calcium, and fluoride. Each of these sensors is designed to maximize user-friendliness and precision, qualities for which HORIBA is globally recognized in water quality testing. HORIBA replacement sensors ensure that users’ devices consistently deliver optimal performance and accurate measurements. Advantages of HORIBA Replacement Sensors: Easy Replacement: Sensors can be replaced quickly, allowing measurements to continue without delay. High Precision: Replacement sensors ensure results are accurate and reliable. Comprehensive Measurement Range: Various sensor types are available to measure a wide range of water quality parameters. Durability: Sensors are designed for long service life even under challenging conditions. Sensor Replacement Instructions: To ensure the longevity and accuracy of your HORIBA LAQUAtwin Pocket Tester, follow these steps when replacing a sensor: Removing the Sensor: Turn off the tester. Slightly move the sensor away from the device and lift the sensor tip. Detach the sensor completely from the tester so there is no connection between the two parts. Installing the Sensor: Ensure the tester is turned off. Check that the waterproof gasket is clean and intact. Attach the sensor to the tester by inserting hook “A” on the back of the device into hole “a” on the sensor tip. Ensure that the waterproof gasket is not twisted. Important: After replacing the sensor, follow the instructions in the user manual of the respective tester to make the device ready for accurate measurement. (These manuals are available with the products. Calibration and, if necessary, conditioning are usually required.) How can I check if my sensor shows signs of wear? Check the sensor condition as follows: Perform a 2-point calibration. If an error occurs during calibration, this indicates that the sensor has deteriorated. In this case, it is recommended to replace the sensor. Regular checks and timely replacement of sensors are essential to ensure the high standards and reliability of water quality measurements performed with HORIBA LAQUAtwin Pocket Testers. Manufacturer Part Nr. 3200934450