OBJECTIVE: Desalination of cheese whey by electrodialysis yields saline wastewater (SWW). The goal was to test this as the basis of a culture medium and to prove experimentally the concept that it was a suitable resource for heterotrophic cultivation of the freshwater green microalga Chlorella vulgaris. RESULTS: Optimization of glucose concentration, nitrogen source and medium salinity for microalgal growth was first carried out in defined medium (DM) and shake flasks. These results were then adopted in shake flask cultivation experiments using pre-treated SWW medium (PSWW). Subsequently, microalgal growth under optimized conditions was tested in bioreactors. Various media such as DM, PSWW and diluted PSWW (DPSWW) were compared. Volumetric biomass productivities decreased in the order DM (0.371 g L-1 h-1, urea) > DPSWW (0.315 g L-1 h-1, soy peptone) > PSWW (0.152 g L-1 h-1, soy peptone). Although biomass productivities in DPSWW and PSWW media were significantly lower than in DM, these media required the addition of only 66 and 33% of DM N sources, respectively. No other added DM component was necessary in (D)PSWW to achieve microalgal growth. CONCLUSIONS: Although the optimized cultivation of freshwater microalgae on alternative medium based on SWW resulted in biomass productivities lower than those on DM, the required addition of N sources was also lower. Potentially lower production costs of Chlorella biomass and the meaningful use of SWW are the main outcomes of this work.

• Klíčová slova
• Biomass, Bioreactor, Chlorella vulgaris, Cultivation, Saline waste water,
• MeSH
• Chlorella vulgaris růst a vývoj   MeSH
• heterotrofní procesy MeSH
• kultivační média chemie   MeSH
• odpadní voda chemie   MeSH
• salinita MeSH
• sýr MeSH
• syrovátka chemie   MeSH
• techniky vsádkové kultivace MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kultivační média MeSH
• odpadní voda MeSH

Saline waste water from demineralization of cheese whey was used as the main component of waste saline medium (WSM) for cultivation of thraustochytrids. The suitability of WSM for cultivation of Schizochytrium limacinum PA-968 and Japonochytrium marinum AN-4 was evaluated by comparison with cultivation on nutrient medium (NM) in shake flask and fermenter cultures. Biomass productivities achieved in WSM for the thraustochytrids were comparable with those in NM for both shake flask and fermenter cultures. The maximum total lipid content (56.71% dry cell weight) and docosahexaenoic acid productivity (0.86 g/L/day) were achieved by J. marinum AN-4 grown on WSM in shake flask and fermenter cultures, respectively. A cost estimate of WSM suggests that this medium could result in lower production costs for thraustochytrid biomass and lipids and contribute to the effective reduction in saline diary process waste water.

• Klíčová slova
• Bioreactor, Docosahexaenoic acid, Japonochytrium marinum, Saline waste water, Schizochytrium limacinum, Shake flask,
• MeSH
• biomasa MeSH
• bioreaktory MeSH
• dusík chemie   MeSH
• elektrody MeSH
• fermentace MeSH
• Heterokontophyta metabolismus   MeSH
• kyseliny dokosahexaenové chemie   MeSH
• lipidy chemie   MeSH
• mastné kyseliny chemie   MeSH
• mlékárenství MeSH
• odpadní voda * MeSH
• potravinářská mikrobiologie ekonomika   metody   MeSH
• průmyslová mikrobiologie ekonomika   metody   MeSH
• soli MeSH
• sýr MeSH
• syrovátka chemie   MeSH
• syrovátkové proteiny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dusík MeSH
• kyseliny dokosahexaenové MeSH
• lipidy MeSH
• mastné kyseliny MeSH
• odpadní voda * MeSH
• soli MeSH
• syrovátkové proteiny MeSH

In this work, we evaluated the valorisation of agricultural waste materials by transforming coconut husks and shells, corncobs and rice straw into biochar for water treatment in aquaculture. We compared the biochars' suitability for removal of organic micropollutants (acetaminophen, oxytetracycline, tetracycline, enrofloxacin, atrazine, diuron and diclofenac) from surface water needed for aquaculture. The biochars were prepared by three methods ranging from inexpensive drum kilns (200 °C) to pyrolysis with biogasfication (350-750 °C). Overall, antibiotics tetracycline and enrofloxacin were the most strongly sorbed micropollutants, and coconut husk biochar prepared at 750 °C was the best sorbent material. Molecular Dynamics simulations indicated that the major sorption mechanism is via π-π stacking interactions and there is a possibility of multilayer sorption for some of the micropollutants. We observed, a strong impact of ionic strength (salinity), which is an important consideration in coastal aquaculture applications. High salinity decreased the sorption for antibiotics oxytetracycline, tetracycline and enrofloxacin but increased diclofenac, atrazine and diuron sorption. We considered coconut husk biochar produced in drum kilns the most practical option for biochar applications in small-scale coastal aquacultures in South Asia. Pilot trials of canal water filtration at an aquaculture farm revealed that micropollutant sorption by coconut husk biochar under real-world conditions might be 10-500 times less than observed in the laboratory studies. Even so, biochar amendment of sand enhanced the micropollutant retention, which may facilitate subsequent biodegradation and improve the quality of brackish surface water used for food production in coastal aquaculture.

• Klíčová slova
• Agricultural waste, Aquaculture, Biochar, Micropollutants, Molecular dynamics simulations, Sorption,
• MeSH
• adsorpce MeSH
• dřevěné a živočišné uhlí MeSH
• simulace molekulární dynamiky * MeSH
• voda * MeSH
• vodní hospodářství MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biochar MeSH Prohlížeč
• dřevěné a živočišné uhlí MeSH
• voda * MeSH

UV-E-chlorination/hematite nanoparticles (UV/E-Cl/HNs) as a heterogeneous photocatalytic activation of electrogenerated chlorine was assessed for the degradation of bisphenol A (BPA) as a new approach based on the generation of reactive chlorine and oxygen species. The prepared sample was characterized using multiple techniques, such as XRD, FTIR, FESEM, EDS, and BET-BJH. An excellent decontamination efficiency of 99.4% was achieved within 40 min of electrolysis under optimum conditions (pH of 5, HNs dosage 100 mg/L, current density of 20 mA/cm2, and NaCl concentration of 50 mM). The HOCl content was reduced more swiftly in the presence of ultraviolet (UV) irradiation and hematite, resulting in the production of oxidative radicals (i.e., •OH, Cl•, and Cl2•-). The scavenging experiments also verified the vital role of these radicals in oxidative treatment. The UV/E-Cl/HNs process is readily supplied with hydroxyl radicals through several mechanisms. Bicarbonate ions showed a noticeable inhibitory impact, whereas nitrate and sulfate anions only slightly affected BPA degradation. The HNs were a recoverable and stable catalyst for six cycles. Furthermore, the ECOSAR program predicted that the UV/E-Cl/HNs can be labeled as an environmental-friendly process. Eventually, reasonable degradation pathways were proposed based on the identified by-products through experimental and theoretical approaches.

• Klíčová slova
• Bisphenol A, Electro-photocatalytic degradation, Reactive oxygen and chlorine species, Saline wastewater, Toxicity assessment,
• MeSH
• chemické látky znečišťující vodu * chemie   MeSH
• chlor chemie   MeSH
• chloridy MeSH
• čištění vody * metody   MeSH
• kinetika MeSH
• kyslík MeSH
• odpadní voda MeSH
• oxidace-redukce MeSH
• ultrafialové záření MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bisphenol A MeSH Prohlížeč
• chemické látky znečišťující vodu * MeSH
• chlor MeSH
• chloridy MeSH
• kyslík MeSH
• odpadní voda MeSH

The work presented here provides a complex environmental impact of sediments in vicinity to the area of the former Lazy coal mine site in the Upper Silesian Coal Basin (Czech Republic). The main aim of this work has been to determine the degree of contamination, to describe the organic matter, and to carry out sorption isotherms to see the size and distribution of pores in the monitored sediments that are the crucial parameters to assumption of removal mechanisms of elements carried in mine water. The results show that the greatest enrichment of Mn, Sr, Ba, and was in sediments of the first tens of meters from the mine water discharge sediments. Ba and Sr were precipitated as mineral barite and thus formed a dominant insoluble component in the river sediments, which were further carried by water flow towards the water reservoirs. Predominant amounts of fossil material and smaller quantities of carbonized and recent organic matter were altered by weathering and erosion processes. The coal materials have a relatively beneficial sorption capacity, which increases with the carbon content. The overburden waste should be considered for use in removing heavy metals in-situ.

• Klíčová slova
• Adsorption capacity, Major and trace elements, Mine water, Organic matter, Sediments,
• MeSH
• chemické látky znečišťující vodu * analýza   MeSH
• geologické sedimenty MeSH
• minerály MeSH
• monitorování životního prostředí MeSH
• řeky MeSH
• těžké kovy * analýza   MeSH
• uhlí MeSH
• voda MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu * MeSH
• minerály MeSH
• těžké kovy * MeSH
• uhlí MeSH
• voda MeSH

Over the past few decades, reverse osmosis (RO) has been the dominant technology employed in zero liquid discharge (ZLD) systems for industrial wastewater treatment (WWT). However, RO is limited to a maximum operating salinity of about 75 g kg-1. Electrodialysis (ED) is a potentially attractive option as it can achieve much higher concentrations, thereby reducing the capacity and energy demand of the subsequent evaporation step. Feed-and-bleed experiments were undertaken on a laboratory-scale ED stack using a series of model solutions based on the most common inorganic salts with the aim of determining maximum achievable concentrations. The maximum salt concentration achievable via ED ranged between 104.2 and 267.6 g kg-1, with levels predominantly limited by water transport. In addition, a straightforward review of how ED incorporation can affect ZLD process economics is presented. The operational cost of an ED-based ZLD system for processing RO retentate was almost 20% lower than comparable processes employing high-efficiency RO and disc tubular RO. As the ED-based ZLD system appears economically preferable, and as maximum achievable concentrations greatly exceeded RO operating limits, it would appear to be a promising approach for bridging the gap between RO and evaporation, and may even eliminate the evaporation step altogether.

• MeSH
• chlorid sodný MeSH
• čištění vody MeSH
• filtrace MeSH
• membrány umělé MeSH
• odpad tekutý - odstraňování metody   MeSH
• odpadní voda MeSH
• osmóza MeSH
• salinita MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chlorid sodný MeSH
• membrány umělé MeSH
• odpadní voda MeSH

Ion-exchange tap water demineralization for process water preparation results in a saline regeneration wastewater (20-100 mS cm(-1)) that is increasingly problematic in view of discharge. A coupled nanofiltration-membrane distillation (NF-MD) process is evaluated for the recovery of water and sodium chloride from this wastewater. NF-MD treatment of mixed regeneration wastewater is compared to NF-MD treatment of separate anion- and cation-regenerate fractions. NF on mixed regeneration wastewater results in a higher flux (30 L m(-2) h(-1) at 7 bar) compared to NF on the separate fractions (6-9 L m(-2) h(-1) at 30 bar). NF permeate recovery is strongly limited by scaling (50% for separate and 60% for mixed, respectively). Physical signs of scaling were found during MD treatment of the NF permeates but did not result in flux decline for mixed regeneration wastewater. Final salt composition is expected to qualify as a road de-icing salt. NF-MD is an economically viable alternative compared to external disposal of wastewater for larger-scale installations (1.4 versus 2.5 euro m(-3) produced demineralized water for a 10 m3 regenerate per day plant). The cost benefits of water re-use and salt recuperation are small when compared to total treatment costs for mixed regenerate wastewater.

• MeSH
• chlorid sodný chemie   izolace a purifikace   MeSH
• čištění vody přístrojové vybavení   metody   MeSH
• destilace přístrojové vybavení   metody   MeSH
• filtrace přístrojové vybavení   metody   MeSH
• membrány umělé MeSH
• odpadní produkty analýza   MeSH
• odpadní voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chlorid sodný MeSH
• membrány umělé MeSH
• odpadní produkty MeSH
• odpadní voda MeSH

Produced water (PW) represents the largest volume waste stream in oil and gas production operations from most offshore platforms. PW is difficult to monitor as releases are rapidly diluted and concentrations can reach trace levels. The use of passive samplers can over come this. Here polyethylene (PE) was calibrated for a diverse range of PW pollutants. Zebrafish were exposed to dilutions of PW and passive sampler extracts in order to investigate the relationship between freely dissolved chemical concentrations and acute toxic effects. The raw PW had an LC50 of 13% (percentage of PW in the standardized zebrafish medium). Observed non-viable deformations to embryos (at 5 hpf) included heart and yolk edema, head, spine and tail deformations. The dose-response relationship of lethal effects showed that if 0.0041 g of PE is exposed to this PW, then extracted, 50% of exposed D. rerio will suffer lethal effects. The sum of tested freely dissolved concentrations that led to 50% lethal effects (mortality and non-viable deformations) was 2.32 × 10-4 mg/L for PW and 7.92 × 10-2 mg/L for PE. This implies that exposure to raw PW was more toxic than exposure to PE extracts. This toxicity was attributed both to the presence of contaminants as well as PW salinity. Passive samplers are able to detect very low freely dissolved pollutant concentrations which is important for assessing the spatial dilution of PW releases. Bioassays provide complimentary information as they account for all toxic compounds including those that are not taken up by passive samplers.

• Klíčová slova
• Deformations, Monitoring, Polyethylene, Produced water, Zebrafish,
• MeSH
• biotest MeSH
• chemické látky znečišťující vodu analýza   chemie   MeSH
• monitorování životního prostředí metody   MeSH
• odpadní voda chemie   MeSH
• průmysl ropy a zemního plynu normy   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• odpadní voda MeSH

Electrodialysis is an electric-field-mediated process separating ions exploiting selective properties of ion-exchange membranes. The ion-exchange membranes create an ion-depleted zone in an electrolyte solution adjacent to the membrane under DC polarization. We constructed a microfluidic system that uses the ion-depleted zone to separate ions from the processed water solution. We tested the separation performance by desalting a model KCl solution spiked with fluorescein for direct observation. We showed both visually and by measuring the conductivity of the output solutions that the system can work in three modes of operation referred to as continuous desalination, desalination by accumulation, and unsuccessful desalination. The mode of operation can easily be set by changing the control parameters. The desalination factors for the model KCl solution reached values from 80 to 100%, depending on the mode of operation. The concentration factor, given as a ratio of concentrate-to-feed concentrations, reached zero for desalination by accumulation when only diluate was produced. The water recovery, therefore, was infinite at these conditions. Independent control of the diluate and concentrate flow rates and the DC voltage turned our system into a versatile platform, enabling us to set proper conditions to process various samples.

• Klíčová slova
• cation-exchange membranes, desalination, ion concentration polarization, ion separation, microfluidics,
• MeSH
• chlorid sodný izolace a purifikace   MeSH
• čištění vody metody   MeSH
• elektrická vodivost MeSH
• elektrody MeSH
• iontová výměna MeSH
• odpadní voda chemie   MeSH
• salinita * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chlorid sodný MeSH
• odpadní voda MeSH

Amongst harvesting processes, alkaline flocculation stands out as a technically feasible and low cost method. The interference of model wastewater components with alkaline flocculation of Chlorella sorokiniana (pH 8-12), induced by calcium phosphate (CaP) precipitates, was evaluated. Between the compounds tested, inorganic nitrogen, sodium alginate, salinity and algal organic matter had no effect on flocculation efficiency (FE). The negative effect of humic acids, sodium dodecyl sulphate and alkalinity on FE was partial. Bovine serum albumin and bacterial organic matter (BOM) of Escherichia coli showed the strongest disruption of FE. The impact of BOM can be explained by the high protein content (65% of total organic carbon). Proteins, negatively charged at alkaline pH, interrupt microalgae flocculation by preferentially interacting with positively charged CaP precipitates. The simultaneous effects of multiple substances were tested to simulate real wastewater. The results confirm the need to investigate the composition of wastewater prior to alkaline flocculation.

• Klíčová slova
• Alkaline flocculation, Chlorella sorokiniana, Interfering compounds, Wastewater,
• MeSH
• biomasa MeSH
• Chlorella * MeSH
• flokulace MeSH
• fosforečnany vápenaté MeSH
• mikrořasy * MeSH
• odpadní voda MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosforečnany vápenaté MeSH
• odpadní voda MeSH