Page 102 - EER-2-3

Explora: Environment
and Resource Comparative analysis of THMs and THAAs in water distribution media

A B

Figure 10. Comparison of detected chlorination disinfection byproducts in water samples and their removal efficiency by filtration setups
Abbreviations: GAC: Granular activated carbon; GI: Galvanized iron; HDPE: High-density polyethylene; THAA: Trihaloacetic acids; THM: Trihalomethane.

Moreover, it was observed that the second filtration on its own to achieve the desired DBP removal due
media setup was more efficient than the first filtration to its limited effect on DOM. In contrast, the GAC
media setup, particularly in the case of the GI pipe. In filter—due to its high adsorptive capacity—can be
the GI pipe water sample, the first filtration media setup considered a more effective and feasible option
removed approximately 36.8% of THAAs and 99% of for removing chlorine DBPs under controlled
THMs. In contrast, for the HDPE pipe, both filtration chlorination. This highlights the superior
setups were effective in removing approximately 99% of performance of adsorption-based over absorption-
chlorine DBPs, due to the lower formation rate of chlorine based filtration techniques
DBPs. This shows that both filtration setups are effective (iv) Optimizing chlorine dosage in the water supply can
in reducing DBPs, although their efficiency may vary help balance effective disinfection while minimizing
depending on pipe material. DBP formation.
However, due to its non-absorptive nature, the second
filtration media setup may not retain chemical contaminants Acknowledgments
through absorption, including DBPs. Instead, it is specifically The authors gratefully acknowledge the technical assistance
designed for the adsorption of organic compounds, featuring provided by the Water Quality Laboratory, Public Health
a GAC layer positioned beneath a sand layer and above a Engineering Department, Khyber Pakhtunkhwa, the
gravel pack, and operates through a multi-stage process. Central Resource Laboratory, University of Peshawar,
Initially, suspended particles, particularly organic matter, the Department of Civil Engineering, University of
are removed by the sand layer. The water then penetrates Engineering and Technology Taxila, and Standard Supply,
the fine GAC medium, where adsorption of DBPs occurs. Peshawar, Khyber Pakhtunkhwa, Pakistan.
Finally, the gravel layer provides additional filtration and
helps stabilize the water’s physical properties. This setup Funding
effectively removes THMs and THAAs under controlled None.
conditions, as shown in Figure 10.
Conflict of interest
4. Conclusion
The authors declare that they have no competing interests.
The following conclusions were drawn from the
investigation of the water samples: Author contributions
(i) The formation of chlorine DBPs—particularly THMs
and THAAs—increased with higher chlorine dosages Conceptualization: Musaab Habib Bangash
under controlled conditions for both pipe materials Investigation: Musaab Habib Bangash
(ii) The material properties of GI pipes—such as their Methodology: Musaab Habib Bangash
tendency to corrode, release metal ions, and trap Writing–original draft: Musaab Habib Bangash
organic matter—contribute more significantly to the Writing–review & editing: Naeem Ejaz, Sadia Nasreen
formation of chlorine DBPs compared to HDPE pipes
(iii) Sand filtration is a cost-effective method for Ethics approval and consent to participate
reducing chlorine DBPs; however, it is insufficient Not applicable.

Volume 2 Issue 3 (2025) 11 doi: 10.36922/EER025240047