Process Water Research Articles

Effective strategy for Cr(VI) removal from water in evolution process of ferroan brucite by redox and intercalation

Cr(VI)-contaminated wastewater treatment is of great significance to ecological environment and human health. In this work, ferroan brucite with different Fe2+ doping amounts (Mg1-XFeX(OH)2, x = 0.1–0.8) were synthesized for the removal of Cr(VI) from wastewater. The effect of Fe content, initial concentration of Cr(VI), reaction time, co-existing ions and pH for Cr(VI) removal performance were examined. As Fe2+ content increased, the removal efficiency initially increased and then decreased, Mg0.4Fe0.6(OH)2 exhibited the maximum removal amount of 494.63 mg/g. Kinetic studies showed Cr(VI) removal well fitted pseudo-second-order model and achieved equilibrium at approximately 40 min. Isotherm data was well described by Langmuir model. The coexisting ions except CO32− had negligible effect, while pH had a significant influence on Cr(VI) removal since different dominated form of Cr(VI) existed at different pH. The removal mechanism towards Cr(VI) under different pH values was explored. At acidic environment, most Cr(VI) in Cr2O72− was reduced to Cr(III) by Fe2+ resulting in the precipitation of (Fe,Mg)(Cr,Fe)2O4, the remaining part was immobilized by interlayer of reaction product LDHs, and the intercalation amounts of Cr2O72− were 114.05 mg/g and 106.78 mg/g at pH of 3 and 6. While under alkaline conditions, most CrO42− entered the interlayer of LDHs with amounts of 262.3 mg/g at pH = 11, and the rest was absorbed on the surface. Furthermore, the reaction product could be recovered as chromite with recovery rate of 83.94 %. The excellent removal performance suggested a promising strategy in sewage water remediation.

Formation and Texture Analysis of Extrusion-Based 3D Printed Foods Using Nixtamalized Corn and Chickpea Flours: Effect of Cooking Process

Extrusion-based three-dimensional (3D) food printing (3DFP) enhances the customization of 3D-printed foods by using multiple food pastes. Post-printing processes like baking are usually necessary and significantly impact the stability of the 3D-printed foods. This study aimed to produce multi-material 3D-printed foods using nixtamalized corn dough and chickpea paste (CP) in extrusion-based 3DFP and to study the effect of post-printing processes (water oven cooking and steam cooking) and the type of material used (single- or multi-material) on the final appearance, weight, size, and texture of the 3D-printed foods. Multi-material 3D-printed foods were successfully produced using extrusion-based 3DFP. Steam-cooked 3D-printed foods cooked uniformly and had a better appearance, as they did not develop surface cracks compared to water oven-cooked foods. Water-oven cooked foods experienced a greater weight loss of 35.6%, and higher height and length reduction of 1.5% and 8.4%, respectively. Steam-cooked multi-material 3D-printed foods were harder at 40% of strain, with force values of 66.9 and 46.3 N for water-oven cooked foods. Post-printing processes, as well as the presence of CP in the middle of the 3D-printed foods, influenced their final appearance, weight, size, and texture. This study offers interesting findings for the innovative design of chickpea- and corn-based multi-material 3D-printed foods.

Cu-doped Ni3S2 electrocatalyst for glycerol oxidation coupling to promote hydrogen evolution reaction

Hydrogen energy is becoming increasingly important as a clean and efficient form of energy. Glycerol oxidation synergistic electrocatalytic hydrogen evolution technology is an electrochemical process that integrates anodic glycerol oxidation reaction (GOR) and cathodic hydrogen production. Compared with the oxygen evolution reaction (OER) required in the electrolysis of water for hydrogen production process, this technology can not only reduce the energy consumption of the whole reaction, but also obtain valuable by-products while producing hydrogen. In this study, we successfully prepared a copper-doped Ni3S2 (Cu-Ni3S2@NF) electrode material loaded on a nickel foam carrier by a two-stage hydrothermal synthesis method, and applied it to the bifunctional electrocatalytic reaction of GOR and hydrogen evolution reaction (HER). After a series of in-depth electrochemical performance tests, it was confirmed that 0.1Cu-Ni3S2@NF showed lower overpotential requirements when performing GOR and HER, requiring only 1.41 V relative to the reversible hydrogen electrode (RHE) to drive a current density of 100 mA cm−2 for GOR, and only 0.56 V vs. RHE to achieve the same current density for HER. Moreover, the electrode material still maintains good stability under long-term operation. Among them, the Faraday efficiency (FE) of glycerol oxidation to formate is more than 85 %, while the FE of HER is not less than 93 %.

Sensory and consumer aspects of sea lettuce (Ulva fenestrata) – impact of harvest time, cultivation conditions and protein level

The green seaweed Ulva fenestrata is a future food candidate, however, both compositional, e.g. protein content, and sensory qualities depend on cultivation and harvest conditions. The aim was to explore sensory qualities of, and consumer attitudes to, U. fenestrata derived from three different cultivation conditions and three harvest times. U. fenestrata was cultivated at sea and in two different land-based tank settings, one mimicking seawater and one with added process water from fishing industry to increase protein content. The seaweed was subjected to sensory analysis performed by an analytical sensory panel and a focus group consisting of consumers. The former assessed the seaweed as dried whole blades (9 samples) and as emulsions (9 samples). Consumers assessed whole blades and a vegan spread enriched with powdered U. fenstrata. All seaweed samples were intensely green; had tastes of umami, salt, bitter, and sour; odours and flavours of grass and fresh seaweed; and had a crispy texture. Cultivation in tanks resulted in a crispier texture than sea cultivation (p<0.001). Protein content increased from 14.4% to 21.6% in tank cultivation with process waters, which increased green colour intensity (p<0.007) and decreased intensity of bitterness (p<0.001). Overall, consumers were positive towards seaweeds as foods.

Determination of Sustainable Factory Locations for the Lemon Agroindustry using AHP, Mapping and Water Management

This research was conducted in Suntenjaya Village, Lembang, and West Bandung Regency, focusing on lemon agro-industrial development. Research was conducted using the Analytical Hierarchy Process (AHP) approach, area mapping, and water management to determine a sustainable factory location. The main objective is the selection of factory sites by integrating lemon production, considering sustainable agriculture aspects, product aspects, and water conservation programs. The results of this study provide a strong foundation for sustainable agro-industrial development that will support sustainable agriculture, local economy, and environmental protection. The research also combined qualitative and quantitative elements with a mixed approach that included Focus Group Discussion (FGD) and AHP, and the results showed that integrated drainage management was the top priority, followed by sanitation, clean water, reforestation, and sustainable agriculture. Mapping of areas based on geographical characteristics, such as rainfall, slope, and soil type, provided a map of water infiltration rates, which became a key guide in planning water conservation programs. The ultimate location for the lemon agroindustry is half of Desa Suntenjaya, mostly from the center to the northern area, which needs to consider proximity to markets in Bandung Regency and City, easy access to sources of raw materials for lemons, water availability, adequate transportation infrastructure, access to energy sources, suitable climate for lemon growth, and the availability of adequate labor in the region.

(Invited) Trials and Tribulations on Scaling Metal Recovery Technology from Lab to Market

PowerTech Water, Inc. d/b/a ElectraMet (ElectraMet) is a cleantech company founded in 2014 in Lexington, KY with the goal of applying carbon and electrochemistry to solve fundamental challenges in wastewater and process water applications. There exists a broad array of separation applications that could be tackled through electrochemical routes, and ElectraMet has worked on many of them.Early in ElectraMet’s history, focus was directed towards salt removal applications such as salt-free water softening, brackish water desalination, and ultra-pure water production. While some traction was found in these spaces, penetration of a new technology versus entrenched incumbents such as reverse osmosis and distillation made the sales process difficult. Limitations in what the technology could and could not do were also determined. Therefore, within the first few years of operation, focus shifted towards particular customer pain points, specifically metals separation applications. Problematic metals concentrations are present in drinking water, industrial effluents, and storm runoff, just to name a few. As a growing but still small business, it is important to choose a beachhead market where you can have the strongest value proposition, and electrochemical separations of metals offered a unique opportunity to solve challenges in the metals separation space. Therefore, considerable work has gone into developing these separation processes for specific metals and specific markets.In this talk, the early history of the company will be reviewed, including technology, funding, and market applications. The impact of strategic advisors and early successes will be discussed with regards to the direction of the company. Ultimately, product-market-fit and the strategies and struggles in building a small business will be presented. Efforts will be made to highlight possible pitfalls, roadblocks, and opportunities as seen through this particular journey.

Analysis of Naphthenic Acid–Salt Interactions in Simulated Oil Sands Process Water

Analysis of Naphthenic Acid–Salt Interactions in Simulated Oil Sands Process Water

Water and Wastewater Management in Production Processes of PGE Energia Ciepła SA Branch 1 in Krakow in Light of Company Modernization

Electricity production requires a very high water consumption. One way to reduce water demand in power plants might be effective wastewater recycling within the power plant, which can lead to almost zero wastewater discharge. The study aims to characterize the functioning of the water and wastewater management system before and after the modernization of a wastewater treatment installation owned by an electricity and heat producer using biomass and other solid fuels. The scope of work covered one of the largest energy companies in Poland: PGE Energia Ciepła SA Branch 1 in Krakow. Water management and the effectiveness of wastewater treatment installation modernization were assessed in terms of the BAT (Best Available Techniques) conclusions. Particular attention was paid to the analysis of changes in the quality parameters of wastewater after the modernization of the wet flue gas desulfurization installation. The research results prove that the modernization of the company’s water and wastewater system significantly reduced the emission of harmful substances into the environment and water consumption. After modernization, an effective reduction in the content of heavy metals and other pollutants in the wastewater was observed. A decrease in the content of cadmium was observed by 99%, nickel—96%, mercury—95%, and copper—83%.

Efficacy of organic acids, lactic and formic acid, and peracetic acid in decontaminating process water and carcasses in chicken slaughter

AbstractFoodborne pathogens pose a persistent threat in broiler chicken production, particularly during the slaughter process, where contamination with zoonotic pathogens remains a concern. This study focuses on the potential of organic acids, such as formic and lactic acid, and the oxidizing agent peracetic acid, to decontaminate scalding water and enhance the hygiene of chicken carcasses. We conducted suspension tests introducing various organic loads to mirror the conditions of practical scalding water. Additionally, the surface tests were performed on chicken skin. Both methods were further tested in an experimental slaughtering facility. In suspension tests, the organic acids achieved impressive decontamination, with a 5‐log10 reduction of the test organisms Enterococcus hirae, Salmonella Typhimurium and Campylobacter jejuni at minimal concentrations (between 0.04% and 2% for formic acid; between 0.1% and 4.5% for lactic acid). Peracetic acid also effectively sanitized model water and chicken skin, even when used in low concentrations (between 0.001% and 0.1%), both in the laboratory‐based testing and in the experimental slaughtering facility. These results suggest that the tested disinfectants can effectively sanitize process water, even under conditions mimicking practical scalding water with organic matter. Peracetic acid, in particular, proved highly effective in improving chicken skin hygiene even at low concentrations.

Efficient reclamation of phosphorus from wetland biomass waste via liquid-recirculated hydrothermal carbonization and precipitation

Hydrothermal carbonization (HTC) for the recovery of phosphorus (P) from biomass wastes has attracted considerable attention, while migration of P to the liquid phase greatly weakened P recovery efficiency and elevated the environmental risk. Therefore, a systematic scheme was proposed in this work to accomplish the complete reclamation of P from wetland plant (Ceratophyllum demersum) through coupling liquid-recirculated HTC mediated by H2O or H2SO4 with precipitation, and the migration and speciation of P during this process was determined by P K-edge X-ray absorption near edge structure, 31P nuclear magnetic resonance, and the modified sequential extraction. The P concentration in the liquid phase increased with the recirculation of HTC process water, and reached up to 550.6 mg L-1. >98.1 % of P in the recirculated liquid products was recovered in the forms of hydroxyapatite and struvite with the HTC mediums of H2O and H2SO4, respectively, without the addition of exogenous metals. In addition to the production of P compounds, P-enriched hydrochar was simultaneously obtained during this process. The HTC medium and liquid recirculation had profound impact on the hydrochar characteristics and the transformation of P. Hydroxyapatite and magnesium phosphate were the dominant P species in the hydrochars derived from H2O-mediated HTC, while FePO4 and other Ca-P species [Ca3(PO4)2 and Ca(H2PO4)2] dominated the P compounds in the H2SO4-mediated hydrochar. These results suggest that coupling liquid-recirculated HTC and precipitation could be a promising strategy for P reclamation, which could provide new insights into the P recovery from biomass waste.

Analysis of intermediate cooling systems for CO2 compression trains of offshore oil wells

A multi-stage compression train with intermediate cooling used to inject carbon dioxide (CO2) in a well is modeled using two distinct configurations, direct and assisted cooling. The main difference between these configurations is that, in the latter, the process water responsible for the intermediate cooling is cooled down by a refrigeration cycle. These configurations are thermodynamically modeled while aiming to investigate the effect of key parameters on two main variables: (i) the overall global conductance and (ii) the overall power consumed by the compressors and auxiliary cooling systems. The results for direct cooling indicate that the power consumed by the compression train is inversely related to the global conductance, while an increase in the number of intermediate compression stages also reduces the global conductance. The assisted cooling, which considered 20 different working fluids for the refrigeration cycle, presented a minimal value for the global conductance for a given value of the overall power consumed by the compressors (train and refrigeration cycle). Finally, a comparison between both configurations reveals that while direct cooling offers a better compromise solution between global conductance and power consumption, assisted cooling can produce a significant reduction of global conductance.

Salt removal from coal flotation product filter cakes using counter-current and displacement washing

Water reuse is a common practice to alleviate water scarcity concerns and mitigate their environmental footprint in coal processing facilities. Nevertheless, water reuse leads to the accumulation of various organic and inorganic substances, including salt and residual reagents in the processing water, potentially leading to the retention of soluble impurities within the coal product. Residual impurities may result in a reduction in the quality of coal products. Salt and moisture retention has become a common issue on-site, but there lacks a proper solution currently. To resolve this industrial problem, investigations were carried out for the effects of washing on removing inorganic impurities from the cake during filtration. Filter cakes were prepared from flocculated metallurgical coal in process water. Two washing methods were trialled namely counter-current washing and displacement washing. Regarding washing efficiency, counter-current washing tended to produce cakes with higher specific resistance, which caused longer filtration time. Displacement washing, however, showed increased filtration time, though to a lesser extent. In addition, washing with different washing liquid ratios for multiple wash cycles showed that the filtration time, specific cake resistance, and medium resistance increased with the number of wash cycles. The analysis of the filtrate indicated that utilising a strategy of displacement washing with a washing ratio of 1:20 yielded the most effective removal of salt. The filter cakes were analysed using the μCT imaging technique to gain insights into the pore structure of the cake at a microscopic level. There was a significant change in the cake structure, where the pore profile was more evenly distributed and smaller when the cake was washed by displacement washing.

Aquaponic growth of basil (Ocimum basilicum) with African catfish (Clarias gariepinus) in standard substrate combined with a Humicacid Fiber-Substrate (HFS)

A major challenge in agriculture, horticulture and aquaponics practices is the reduction of mineral fertilisers and peat to reduce CO2 emissions and increase sustainability. This study used a three-phase-natural fertiliser, the Humicacid Fiber-Substrate (HFS), made from natural regenerative organic and mineral-fractions (Humus-Mineral-Complex), to reduce the peat content in plant pots for aquaponics farming. Basil (Ocimum basilicum) growth was compared with i) 100% standard media substrate ("Einheitserde", white peat 80%, clay 20%), and ii) 85% "Einheitserde" and 15% of HFS under irrigation with aquaculture process waters from an extensive and intensive production of African catfish (Clarias gariepinus) under coupled aquaponic conditions. The substitution with 15% HFS and use of intensive fish water resulted in comparable plant growth to a fertiliser solution as control, and in higher leaf width and leaf green weight and lower root dry weight compared with the standard media substrate "Einheitserde". Basil leaf chlorophyll content from the aquaponics was higher compared with local market plants. This suggests the possible substitution of the peat substrate "Einheitserde" with at least 15% HFS to reduce the natural peat fraction. Further studies on crop-specific substrates are needed to reduce peat in aquaponics farming plant cultivation.

Attenuation of phenylnaphthenic acids related to oil sands process water using solar activated calcium peroxide: Influence of experimental factors, mechanistic modeling, and toxicity evaluation

Refractory naphthenic acids (NAs) are among the primary toxic compounds in oil sands process water (OSPW), a matrix with a complex chemical composition that poses challenges to its remediation. This study evaluated the effectiveness of calcium peroxide (CaO2) combined with solar radiation (solar/CaO2) as an advanced water treatment process for degrading model NAs (1,2,3,4-tetrahydronaphthalene-2-carboxylic acid, pentanoic acid, and diphenylacetic acid) in synthetic water (STW) and provide preliminary insights in treating real OSPW. Solar light and CaO2 acted synergistically to degrade target NAs in STW (>67 of synergistic factor) following a pseudo-first-order kinetic (R2 ≥ 0.95), with an optimal CaO2 dosage of 0.1 g L–1. Inorganic ions and dissolved organic matter were found to hinder the degradation of NAs by solar/CaO2 treatment; however, the complete degradation of NAs was reached in 6.7 h of treatment. The main degradation mechanism involved the generation of hydroxyl radicals (•OH), which contributed ∼90% to the apparent degradation rate constant (K), followed by H2O2 (4–5%) and 1O2 (0–5%). The tentative transformation pathways of three NAs were proposed, confirming an open-ring reaction and resulting in short-chain fatty acid ions as final products. Furthermore, a reduction in acute microbial toxicity and genotoxic effect was observed in the treated samples, suggesting that solar/CaO2 treatment exhibits high environmental compatibility. Furthermore, the solar/CaO2 system was successfully applied as a preliminary step for real-world applications to remove natural NAs, fluorophore organic compounds, and inorganic components from OSPW, demonstrating the potential use of this technology in the advanced treatment of oil-tailing-derived NAs.

An evaluation of pyrite as a component of respirable coal dust

Over the past two decades, the rise in coal worker’s pneumoconiosis has prompted research into the effects of respirable coal dust components. This study explores how coal-pyrites produce hydroxyl radicals (•OH), a reactive oxygen species closely associated with particle toxicity, and assesses the ability of safe chemical additives to reduce •OH production at various pH levels. Promising candidates were evaluated in various solutions, including tap and process waters and simulated lung fluid. We employed electrokinetic measurements, infrared and X-ray photoelectron spectroscopies, and ab initio atomistic simulations to analyze particle surfaces. The study also looked at how surface aging affects •OH production. Our results show that •OH generation of the pyrite varies and is catalyzed by elements like silicon, aluminum, and iron in pyrite. Carboxymethyl cellulose was effective in reducing •OH production by targeting surface sulfide and silicon sites and affecting surface hydration and charge. Atmospheric aging was found to increase •OH production, especially in the pyrite with high iron and silicon and low calcium contents, relative to other samples. This highlights the role of the pyrite surface properties and chemical composition, and the solution pH and composition in •OH generation by coal-pyrites.

Analytical characterization of damage in reverse osmosis membranes caused by components of a chlorine dioxide matrix

Reverse osmosis (RO), an important membrane technology for producing process and tap water, faces challenges due to biofilms formed by viable microorganisms, which significantly impair membrane performance. Disinfection is commonly employed to suppress biofilm formation but can also damage the crucial selective upper layer of the membrane. The present study aims to improve and compare analytical methods for detecting membrane damage to aid the design of targeted disinfection approaches that do not compromise RO efficiency. To achieve this, the accompanying byproducts of in-situ formed chlorine dioxide are analyzed individually with regards to their harmfulness for RO membranes. Combined insights from ATR-FTIR investigations, the methylene blue (MB) dye test, and XPS measurements enable a systematic assessment of the chemical constituents in the chlorine dioxide, ranking their harmfulness as: chlorite < persulfate < purified chlorine dioxide < free chlorine. Further investigations reveal that mechanical stress in the form during disinfection significantly accelerates membrane damage during disinfection. The results of this study pave the way for improved RO processes that account for the effects of chemical byproducts and mechanical stresses to balance disinfection efficacy and membrane integrity for environmentally sustainable water purification solutions.

A Critical Review of Systems for Bioremediation of Tannery Effluent with a Focus on Nitrogenous and Sulfurous Species Removal and Resource Recovery

Tanneries generate copious amounts of potentially toxic sludge and effluent from the processing of skins and hides to leather. The effluent requires remediation before discharge to protect the receiving environment. A range of physicochemical methods are used for pre- and post-treatment, but biological secondary remediation remains the most popular choice for the reduction of the organic and macronutrient fraction of tannery effluent. This review provides an update and critical discussion of biological systems used to remediate tannery effluent. While the conventional activated sludge process and similar technologies are widely used by tanneries, they have inherent problems related to poor sludge settling, low removal efficiencies, and high energy requirements. Treatment wetlands are recommended for the passive polishing step of beamhouse effluent. Hybrid systems that incorporate anoxic and/or anaerobic zones with sludge and/or effluent recycling have been shown to be effective for the removal of organics and nitrogenous species at laboratory scale, and some have been piloted. Novel systems have also been proposed for the removal and recovery of elemental sulfur and/or energy and/or process water in support of a circular economy. Full-scale studies showing successful long-term operation of such systems are now required to convince tanneries to modernize and invest in new infrastructure.

Phytoremediation of metals in oil sands process affected water by native wetland species

Process affected water and other industrial wastewaters are a major environmental concern. During oil sands mining, large amounts of oil sands process affected water (OSPW) are generated and stored in ponds until reclaimed and ready for surface water discharge. While much research has focused on organics in process waters, trace metals at high concentrations may also pose environmental risks. Phytoremediation is a cost effective and sustainable approach that employs plants to extract and reduce contaminants in water. The research was undertaken in mesocosm scale constructed wetlands with plants exposed to OSPW for 60 days. The objective was to screen seven native emergent wetland species for their ability to tolerate high metal concentrations (arsenic, cadmium, copper, chromium, copper, nickel, selenium, zinc), and then to evaluate the best performing species for OSPW phytoremediation. All native plant species, except Glyceria grandis, tolerated and grew in OSPW. Carex aquatilis (water sedge), Juncus balticus (baltic rush), and Typha latifolia (cattail) had highest survival and growth, and had high metal removal efficiencies for arsenic (81–87 %), chromium (78–86 %), and cadmium (74–84 %), relative to other metals; and greater than 91 % of the dissolved portions were removed. The native plant species were efficient accumulators of all metals, as demonstrated by high root and shoot bioaccumulation factors; root accumulation was greater than shoot accumulation. Translocation factor values were greater than one for Juncus balticus (chromium, zinc) and Carex aquatilis (cadmium, chromium, cobalt, nickel). The results demonstrate the potential suitability of these species for phytoremediation of a number of metals of concern and could provide an effective and environmentally sound remediation approach for wastewaters.

Towards a Canadian National River Water Quality-Modelling System: State of Science and Future Prospects

Water quality is of significant concern and ultimately critical to every Canadian’s quality of life and security. Canada has diverse and vast landscapes and stressors that impact various waterbodies differentially, with influencing factors including contaminant and nutrient loads from human activity (mining effluent, wastewater, agricultural runoff, plastics), landscape change (wetland drainage, urbanization) and climate change (warming water temperatures, longer open water seasons, extreme hydrological events, intensifying wildfires). Canadian rivers are especially important to the overall biogeochemistry, hydrology, biodiversity, and ultimate health of aquatic and terrestrial ecosystems. While each of Canada’s provinces and territories has extensive river water quality (physical, chemical, biotic) data and monitoring programs, Environment and Climate Change Canada coordinates various national programs that contribute to the collection and consolidation of these data and conducts extensive research into the study and modelling of key river water quality processes. Despite program-specific efforts, there remains poor capacity to predict current and future conditions in monitored and unmonitored Canadian rivers, particularly remote or northern rivers, due to a myriad of factors including lack of coordination amongst groups and examination of areas in which modelling efforts might be integrated. Herein, we review and analyse the current state of data availability, process studies, and modelling systems for Canadian river water quality. Our synthesis reveals that specific physical processes (water temperature, ice formation, permafrost thaw, sediment dynamics), biogeochemical processes (dissolved oxygen, dissolved organic matter, nutrient cycling, metals/contaminants) and ecological/biological features (biota mass, functional indicators) are well understood, though complex, and are amenable to empirical or mechanistic modelling. Review of this information assists us in identifying opportunities and challenges for developing a national water quality modelling system (NWQMS), that would eventually include similar modelling activities for parallel processes in lakes and integrated watersheds. We identify needs for stronger coordination of monitoring programs in remote areas, recommend use of novel remote sensing technologies, and development of a flexible, iterative ‘process’ for integrated modelling to which stakeholders beyond government can contribute. Such a platform would support short and long-term predictive models of Canadian water quality and ecosystem health, inform effluent concentration limits, and be an early warning system for source waters.

Algorithm-based segmentation of temperature-depth profiles: Examples from a mine

Temperature can be a valuable indicator for the identification and quantification of water fluxes in surface and subsurface water bodies. Therefore, the measurement and analysis of vertical temperature profiles is an important part of the characterization of a water body. Besides its easy application and widespread use, the analysis of temperature profiles can be complex due to its nature as a non-stationary measurement in a dynamic system. This work presents a data-based algorithm to process and segment vertical water temperature profiles avoiding subjectivity in the quantitative analysis of these profiles. Special emphasis is given to studying the reproducibility and precision of the method from data acquisition to data processing and analysis. The presented method provides a blueprint for adjacent applications and showcases the explanatory power of vertical profiles of water temperature to study water fluxes.