Harnessing waterfleas for water reclamation: A nature-based tertiary wastewater treatment technology
Data files
Mar 14, 2024 version files 72.90 KB
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Abdullahi_Arsenic_-_Daphnia_tissue.csv
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Abdullahi_Other_Inorganics.csv
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Abdullahi_recovery_individual.xlsx
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Abdullahi_Recovery_wastewater.xlsx
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Abdullahi_Removal_Efficiency_individual.xlsx
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Abdullahi_Removal_efficiency_prototype.xlsx
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Abdullahi_removal_efficiency_wastewater.xlsx
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README.md
Abstract
Urbanisation, population growth, and climate change have put unprecedented pressure on water resources, leading to a global water crisis and the need for water reuse. However, water reuse is unsafe unless persistent chemical pollutants are removed from reclaimed water.. State-of-the-art technologies for the reduction of persistent chemical pollutants in wastewater typically involves high operational and energy costs and potentially generates toxic by-products (e.g., bromate from ozonation). Nature-base solutions are preferred to these technologies for their lower environmental impact. However, so far, bio-based tertiary wastewater treatments have been inefficient for industrial-scale applications. Moreover, they often demand significant financial investment and large infrastructure, undermining sustainability objectives. Here, we present a scalable, low-cost, low-carbon, and retrofittable nature-inspired solution that could be retrofitted into current wastewater treatment systems to remove persistent chemical pollutants. The technology uses the water flea Daphnia to non-selectively uptake and retain persistent chemical pollutants (pharmaceutical, pesticides and industrial chemicals). We showed Daphnia’s removal efficiency at laboratory scale ranging between 50% for PFOS and 90% for diclofenac. We validate the removal efficiency of diclofenac at prototype scale showing sustained performance over four weeks in outdoor seminatural conditions. A techno-commercial analysis on the Daphnia-based technology suggests several technical, commercial and sustainability advantages over established and emerging treatments at comparable removal efficiency, benchmarked on available data on individual chemicals. Further testing of the technology is underway in open flow environments holding real wastewater. The technology has the potential to improve the quality of wastewater effluent meeting requirements to produce water appropriate for reuse in irrigation, industrial application, and household use. By preventing persistent chemicals from entering waterways, this technology has the potential to maximise the shift to clean growth, enabling water reuse, reducing resource depletion and preventing environmental pollution.
README: Harnessing waterfleas for water reclamation: a nature-based tertiary wastewater treatment technology
Description of the data and file structure
Abdullahi_Recovery_individual-Recovery of individual chemicals. Recovery of PFOS, diclofenac, atrazine and arsenic in the exposures of the four genotypes of Daphnia magna used in this study (Genotype ID) to individual chemicals. The two technical replicates (replicate) and the day of the experiment (Day; the experiments were conducted over 3 days) are shown. Control refers to the chemical control run alongside the exposures.
Abdullahi_Removal Efficiency- Removal efficiency of individual chemicals. Removal efficiency of four individual chemicals (PFOS, diclofenac, atrazine and arsenic) quantified in spiked borehole water in laboratory-controlled conditions. Genotype ID (DM1900; DM1960; DM1980; and DM2015); replicate (rep); day of exposure (day); concentration of the chemical without Daphnia (Initial Concentration; IC this is the chemical control in Table S2); concentration of the chemical after exposure to Daphnia after three days (Final Concentration; FC); and removal efficiency (RE) calculated as [initial concentration final concentration /starting concentration] 100 are shown.
Abdullahi_Recovery_wastewater-Recovery of chemicals from wastewater. Recovery of PFOS and diclofenac in the exposure of the four genotypes of Daphnia magna used in this study (Genotype ID) to wastewater. The two technical replicates (replicate) and the day of the experiment (Day; the experiments were conducted over 3 days) are shown. Control refers to the chemical control run alongside the exposures
Abdullahi_Removal_efficiecny-Removal efficiency from wastewater. Removal efficiency of two chemicals (PFOS and diclofenac) from wastewater by the four genotypes (genotype ID) used in the study. Replicate (rep); day of exposure (day); concentration of the chemical without Daphnia (Initial Concentration; IC this is the chemical control in Table S4); concentration of the chemical after exposure to Daphnia after three days (Final Concentration; FC); and removal efficiency (RE) calculated as [initial concentration final concentration /starting concentration] 100 are shown.
Abdullahi_Removal_efficiecy_prototype-Removal efficiency of diclofenac in the outdoor prototype. Removal efficiency of diclofenac in the outdoor prototype quantified in spiked borehole water with 2mg/L of diclofenac. Sample ID, the week and day of sampling; concentration of the chemical on the day of spiking (Initial Concentration; IC); concentration of the chemical after daily exposure to Daphnia (Final Concentration; FC); and removal efficiency (RE) calculated as [initial concentration final concentration /starting concentration] 100 are shown. Missing FC and RE are on the days in which the prototype was spiked with 2mg/L of diclofenac.
Abdullahi_other_Inorganics: removal of organics and inorganics by Daphnia from aeration tanks and secondary clarifiers. Every 3 days and up to 4 weeks the following parameters were measured: Suspended Solids (SS), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), ammonia and pH.
Abdullahi_Arsenic - Daphnia tissue: Arsenic quantified in the four genotypes of Daphnia across three days. Genotype ID (DM1900; DM1960; DM1980; and DM2015); replicate; day of exposure; treatment (Arsenic versus control) and concentration of Arsenic retrieved in the Daphnia tissue (ng/L) are shown.
Replicate ("1, 2, 3")- Technical replicates for both chemical controls run along side the exposures across
Methods
A total of 216 exposures were completed to quantify the removal efficiency of four classes of chemicals-an industrial chemical (PFOS: 70ng/L; CAS:2795-39-3), a biocide (atrazine:0.2 mg/L; CAS:1912-24-9), a pharmaceutical (diclofenac: 2 mg/L; (CAS:15307-79-6) and a heavy metal (arsenic 1 mg/L; CAS: 7784-46-5), by four genotypes of Daphnia manga: DM1900; DM1960; DM1980; and DM2015. Following an acclimation phase, the removal efficiency of the four genotypes was quantified following exposure to individual chemicals and chemical mixtures from wastewater. the removal efficiency was quantified for PFOS, diclofenac and atrazine over three days with ultraperformance liquid chromatography (UPLC) coupled with high-resolution mass spectrometry. Arsenic samples were quantified using a Nexion 300X inductively coupled plasma mass spectrometer (ICP-MS) (PerkinElmer, Seer Green, U.K) fitted with a cyclonic spray chamber. The removal efficiency of the chemicals was calculated as [starting concentration - final concentration / starting concentration] x 100. Removal efficiency variation by genotype and day was assessed through an ANOVA analysis using the Satterthwaite's method (lmerTest package in R).
We assessed removal efficiency of other inorganics from secondary treated wastewater by Daphnia in laboratory conditions over a period of 3 weeks. Using the HACH colorimeter, we tested removal efficiency of ammonia, total phosphorus and nitrogen, chemical oxygen demand (COD), suspended solids and pH. This quantitation was done on wastewater sourced from the Finham treatment plant from both aeration tanks and the secondary clarifiers. After collection, the wastewater was equally split in triplicate 20L aquaria and inoculated with Daphnia at a density of 100 individuals/L. The inorganics were quantitated twice a week over 3 weeks.
Having identified the strains with the highest removal efficiency in the laboratory exposures, we tested removal efficiency of a population of these strains in a prototype of the technology in outdoor conditions for four weeks to test whether the removal efficiency at scale was comparable to the one measured in the laboratory experiments and to measure performance over time. The prototype was filled with borehole water spiked with diclofenac, a common anti-inflammatory present in wastewater. Removal efficiency was tested daily over a period of 4 weeks using the same approach described for laboratory-based experiments.
Usage notes
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