Growth dynamics and pollutant removal efficiency of the cyanobacterium Komvophoron sp. in flowback and produced water

This study explores the use of a native hypersaline microalgae strain from Oklahoma, Komvophoron sp., for dual purposes: treating Flowback (FW) and Produced Water (PW), and generating algal biomass. The wastewaters were analyzed before and after treatment, and the resulting biomass was characterized for moisture, volatile matter, fixed carbon, and ash content. Komvophoron sp. thrived in both FW and PW, achieving higher biomass concentrations when cultivated in PWs compared to FWs despite nutrient limitations. It also showed high specific growth rates in both water types. The biomass had an energy content of 16–17 MJ kg⁻¹, suitable for biofuel feedstock, although salinity slightly reduced this value. Algal cultivation fully removed ammonia and significantly reduced nitrate, phosphate, boron, and metals such as zinc, manganese, and iron. This approach shows strong potential for reducing the environmental impact of hydraulic fracturing while producing biomass for biofuels and other industrial uses.

1. IPAA, Indipendent Petroleum Association of America. Accessed 16.07.2025. Available from

https://www.ipaa.org/fracking/.

2. Zhang Y, Mao J, Mao J, et al. Towards sustainable oil/gas fracking by reusing its process water: A review on fundamentals, challenges, and opportunities. J Petrol Sci Eng 2022;213:110422. DOI: https://doi.org/10.1016/j.petrol.2022.110422

3. Fajfer J, Lipińska O, Konieczyńska M. Hydraulic fracturing flowback chemical composition diversity as a factor determining possibilities of its management. Environ Sci Pollut Res 2022;29:16152–75. DOI: https://doi.org/10.1007/s11356-021-16432-7

4. EIA, U.S Energy Information Administration. Number of Producing Gas Wells. Accessed 16. 06.2025a. Available from https://www.eia.gov/dnav/ng/ng_prod_wells_s1_a.htm

5. Research and Market. Accessed 12.06.2025. Available from https://www.globenewswire.com/news-release/2025/06/04/3093847/28124/en/North-America-Natural-Gas-Industry-Report-2025-Rising-LNG-Infrastructure-and-Shale-Activity-Propel-Market-Expansion-Competition-Forecast-and-Opportunities-to-2030.html

6. IER Institute for Energy Research. Global oil and gas proved reserves increase in 2021. Accessed 18.06.2025. Available from https://www.instituteforenergyresearch.org/fossil-fuels/gas-and-oil/global-oil-and-gas-proved-reserves-increase-in-2021/

7. LandGate Corp. The environmental impact of fracking on water resources. Accessed 17.06.2025. Available from https://www.landapp.com/post/the-environmental-impact-of-fracking-on-water-resources

8. EIA. U.S Environmental Protection Agency. Class II oil and gas related injection wells. Accessed 17.06.2025. Available from. https://www.epa.gov/uic/class-ii-oil-and-gas-related-injection-wells

9. U.S. Environmental Protection Agency. Hydraulic fracturing for oil and gas: impacts from the hydraulic fracturing water cycle on drinking water resources in the United States (Final Report). Washington, DC, EPA/600/R-16/236F. 2016. Accessed 15.06.2025. Available from www.epa.gov/hfstudy.

10. Emmons RV, Shyma Sunder GS, Liden T, et al. Unraveling the complex composition of produced water by specialized extraction methodologies. Environ Sci Technol 2022;56:2334–44. DOI: https://doi.org/10.1021/acs.est.1c05826

11. Miranda MA, Ghosh A, Mahmodi G, et al. Treatment and recovery of high-value elements from produced water. Water 2022;14:880. DOI: https://doi.org/10.3390/w14060880

12. Herawati N, Dahlan MD, Yusuf M, et al. Removal of total dissolved solids from oil-field-produced water using ceramic adsorbents integrated with reverse osmosis. Materials Today Proc 2023;87:360-5. DOI: https://doi.org/10.1016/j.matpr.2023.03.624

13. Veil J. U.S. produced water volumes and maagement practices in 2017. Ground Water Research and Education Foundation. pag 1-137. Accessed 18.06.2025. Available from https://www.veilenvironmental.com/publications/pw/pdf

14. Hwang B, Heo J, Lim C, Park J. Environmental implications of shale gas hydraulic fracturing: A comprehensive review on water contamination and seismic activity in the United States. Water 2023;15:3334. DOI: https://doi.org/10.3390/w15193334

15. Wertz J. Oklahoma oil regulators adding limits on fracking to earthquake-reduction plan. (December 9, 2016). NPR. Accessed 20.06.2025.

16. EIA. U.S Environmental Protection Agency. Oil and gas extraction effluents guidelines. Part 435. Accessed 18.11.2025c. Available from https://www.ecfr.gov/current/title-40/chapter-I/subchapter-N/part-435

17. Concas A, Lutzu GA, Dunford NT. Experiments and modeling of Komvophoron sp. growth in hydraulic fracturing wastewater. Chem Eng J 2021a;426:131299. DOI: https://doi.org/10.1016/j.cej.2021.131299

18. Lutzu GA, Concas A, Dunford NT. Microalgae growth in physically pre-treated wastewater generated during hydraulic fracturing. Chem Eng Trans 2022;92:661-6.

19. Lutzu GA, Concas A, Dunford NT. Characterization of hypersaline Oklahoma native microalgae cultivated in flowback and produced water: Growth profile and contaminant removal. Bioprocess Biosyst Eng 2024;47:665-81. DOI: https://doi.org/10.1007/s00449-024-02992-8

20. Lutzu GA, Marin MA, Concas A, Dunford NT. Nutrient enrichment of wastewater generated during hydraulic fracturing with animal wastewater to enhance microalgae growth. Chem Eng Trans 2021;86:115-20.

21. AlgaeBase. Accessed 29.05.2025. Available from https://www.algaebase.org/search/genus/detail/?genus_id=44054.

22. U.S. Environmental Protection Agency. Standard method 5220 D, in Federal Register. p. 268111-26812. 1980.

23. Benko KL, Drewes JE. Produced water in the Western United States: Geographical distribution, occurrence, and composition. Environ Eng Sci 2008;25:239-46. DOI: https://doi.org/10.1089/ees.2007.0026

24. Parikh J, Channiwala SA, Ghosal GK. A correlation for calculating HHV from proximate analysis of solid fuels. Fuel 2005; 84:487-94. DOI: https://doi.org/10.1016/j.fuel.2004.10.010

25. American Public Health Association-APHA. Standard methods for the examination of water and wastewater 21th Edition. American Water Works Association, Water Pollution Control Federation. p. 2-48. 2005.

26. Lutzu GA, Dunford NT. Growing algae in produced water generated during oil and gas production using hydraulic fracturing technology. Chem Eng Trans 2019;74:1261-6.

27. Sukarni S. Thermogravimetric analysis of the combustion of marine microalgae Spirulina platensis and its blend with synthetic waste. Helyon 2020;6:e04902. DOI: https://doi.org/10.1016/j.heliyon.2020.e04902

28. Dębowski M, Zielinski M, Swica I, Kazimierowicz J. Algal biomass as a potential source of liquid fuels. Phycol 2021;1:105-18. DOI: https://doi.org/10.3390/phycology1020008

29. Frac focus chemical disclosure registry - FFCDR 2019. Accessed 26.01.2025. Available from https://fracfocus.org/

30. Cluff MA, Hartsock A, MacRae JD, et al. Temporal changes in microbial ecology and geochemistry in produced water from hydraulically fractured Marcellus shale gas wells. Environ Sci Technol 2014;48:6508-17. DOI: https://doi.org/10.1021/es501173p

31. NAABB. The national alliance for advanced biofuels and bioproducts Final Report. Department of Energy. USA. Accessed 02.02.2025. Available from https://www.energy.gov/sites/prod/files/2014/07/f18/naabb_synopsis_report_0.pdf

32. Lutzu GA, Dunford NT. Algal treatment of wastewater generated during oil and gas production using hydraulic fracturing technology. Environ Technol 2019a;40:1027-34. DOI: https://doi.org/10.1080/09593330.2017.1415983

33.Racharaks R, Ge X, Li Y. Cultivation of marine microalgae using shale gas flowback water and anaerobic digestion effluent as the cultivation medium. Bioresour Technol 2015;191:146-56. DOI: https://doi.org/10.1016/j.biortech.2015.04.065

34. Wang H, Lu L, Chen X, et al. Geochemical and microbial characterizations of flowback and produced water in three shale oil and gas plays in the central and western United States. Water Res 2019;164:114942. DOI: https://doi.org/10.1016/j.watres.2019.114942

35. Fecteau KM, Boyd ES, Lindsay MR, et al. Cyanobacteria and algae meet at the limits of their habitat ranges in moderately acidic hot springs. J Geophys Res Biogeosci 2022;127:e2021JG006446. DOI: https://doi.org/10.1029/2021JG006446

36. Zhu Y, Dunford NT. Growth and biomass characteristics of Picochlorum oklahomensis and Nannochloropsis oculata. J Am Oil Chem Soc 2013;90:841-9. DOI: https://doi.org/10.1007/s11746-013-2225-0

37. Zhou N, Dunford NT. Characterization of green microalgae and cyanobacteria isolated from Great Salt Plains. Trans ASABE 2017;60:283-90. DOI: https://doi.org/10.13031/trans.12136

38. Liu J, Vyverman W. Differences in nutrient uptake capacity of the benthic filamentous algae Cladophora sp., Klebsormidium sp. and Pseudanabaena sp. under varying N/P conditions. Bioresour Technol 2015;179:234-42. DOI: https://doi.org/10.1016/j.biortech.2014.12.028

39. Erratt K, Creed I, Chemali C, et al. Performance and competitiveness of red vs. green phenotypes of a cyanobacterium grown under artificial lake browing. Algae 2021;36:195-206. DOI: https://doi.org/10.4490/algae.2021.36.7.19

40. Miazek K, Kratky L, Sulc R, et al. Effect of organic solvents on microalgae growth, metabolism and industrial bioproduct extraction: A review. Int J Mol Sci 2017;18:1429-60. DOI: https://doi.org/10.3390/ijms18071429

41. Patel SN, Sonani RR, Roy D, et al. Exploring the structural aspects and therapeutic perspectives of cyanobacterial phycobiliproteins. 3 Biotech 2022;12:224. DOI: https://doi.org/10.1007/s13205-022-03284-2

42. Gad AH. Cataloguing the bacterial community of the Great Salt Plains, Oklahoma using 16s rRNA based metagenomics pyrosequencing. Genomics Data 2017;12:54-7. DOI: https://doi.org/10.1016/j.gdata.2017.03.002

43. Kochhar N, Kavya IK, Shrivastava S, et al. Perspectives on the microorganism of extreme environments and their applications. Curr Res Microb Sci 2022;3:100134. DOI: https://doi.org/10.1016/j.crmicr.2022.100134

44. Guo L, Xie Y, Sun W, et al. Research progress of high-salinity wastewater treatment technology. Water 2023;15:684. DOI: https://doi.org/10.3390/w15040684

45. Saavedra R, Muñoz R, Taboada ME, et al. Comparative uptake study of arsenic, boron, copper, manganese and zinc from water by different green microalgae. Bioresour Technol 2018;263:49-57. DOI: https://doi.org/10.1016/j.biortech.2018.04.101