In order to manage water resources in countries with water crisis, recycling of water in houses can be a practical strategy. The usage of advanced oxidation processes (AOPs) is an efficient way when ...a low volume of wastewater is considered. In this work, a real washing machine effluent (WME) was treated by four electrochemical advanced oxidation processes. Electro-Fenton (EF) and photoelectro-Fenton (PEF) processes are combined with peroxymonosulfate (PMS) to treat WME. Heterogeneous iron-based catalyst (Fe3O4, MNPs) was synthesized as catalyst for all processes. The characteristics of MNPs were determined by several techniques. All operating parameters were investigated for EF, PEF, EF/PMS and PEF/PMS. PEF/PMS process removed nearly complete organic compounds (99.5% of chemical oxygen demand and 97.1% of total organic carbon) under the conditions of pH=5.0, 30mA/cm2, MNPs=100mg/L, 2mM PMS and 180min reaction time. MNPs function was without change after three times usage. The results indicated that PEF/PMS can be a new system for treatment of effluents such as greywater, washing machine etc. for the application in household scale to reduce water consumption.
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•Photoelectro-Fenton with Fe3O4 is combined with peroxymonosulfate (PEF/PMS).•PEF/PMS is applied to treat washing machine effluent.•Complete treatment was achieved in terms of color and COD.•PEF/PMS can be used as decentralized system to treat wastewaters with low volume.
The washing of synthetic clothes is considered to be a substantial source of microplastic to the environment. Therefore, various devices have been designed to capture microfibres released from ...clothing during the washing cycle. In this study, we compared 6 different devices which varied from prototypes to commercially available products. These were designed to either be placed inside the drum during the washing cycle or fitted externally to filter the effluent wastewater discharge. The aim of this study was to examine the efficacy of these devices at mitigating microfibre release from clothing during washing or at capturing any microfibres released in the wastewater. When compared to the amount of microfibres entering the wastewater without any device (control), the XFiltra filter was the most successful device. This device captured microfibres reducing their release to wastewater by around 78%. The Guppyfriend bag was the second most successful device, reducing microfibre release to wastewater by around 54%; it appeared to mainly work by reducing microfibre shedding from the clothing during the washing cycle. Despite some potentially promising results it is important to recognise that fibres are also released when garments are worn in everyday use. Researchers and industry need to continue to collaborate to better understand the best intervention points to reduce microfibre shedding, by considering both product design and fibre capture.
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•This study tested the efficiency of six devices available in 2018.•XFiltra was 78% efficient at reducing microfibre loss to wastewater.•External filters were more successful at microfibre capture.•In-drum inventions helped reduce microfibre release from clothing itself.•Independent research is essential to establish optimum intervention points.
Real effluent of washing machine is one of the major sources of microplastics and fabrics in municipal and surface water. The effluents constitute large volume of wastewater with different ...surfactants since every household and industries nowadays use washing machine rather than traditional hand washing.
In this work, a real effluent of washing machine was treated by electrooxidation (EO) in a pre-pilot plant scale electrochemical flow reactor using active (Ti/Pt) or non-active (boron doped diamond (BDD)) anodes and Ti cathode. The effect of anode material (Ti/Pt or BDD) and the applied current density (16.6, 33.3 and 66.6 mA cm−2) on the decay of the organic matter, in terms of chemical oxygen demand (COD) during the electrochemical treatment was examined using the as-received effluent or by adding Na2SO4 as supporting electrolyte (as auxiliary in the conductivity). A decreased in organic matter (COD) was always observed when an increase on the applied current density was achieved at both anodes; however, BDD anode showed a well-defined trend as well as higher removal efficiency at all current densities studied when compared to Ti/Pt. Besides, faster and higher COD decay was attained by adding Na2SO4 to the real effluent compared to as-received effluent regardless of anode material used. Active chlorine species were also electrochemically produced at both anodes from the Cl− ions in the real effluent, contributing to the elimination of the pollutants. The mineralization of organic matter in the effluent was also determined, obtaining >90% of total organic carbon (TOC) reduction after 360 min with BDD anode at 33.3 and 66.6 mA cm−2. Based on the achieved results, EO is an efficient and effective treatment approach for the remediation of organic micropollutants in washing machine effluent especially with BDD anode.
•Real washing machine effluent was efficiently treated by BDD-electrolysis•No efficient depollution was achieved when Ti/Pt (active) anode was used•Cl− ions in the real effluent promoted the production of active chlorine•˙OH produced by BDD-electrolysis reacts with SO4–2 to form S2O82−
Microplastics are widely spread in the environment, which along with still increasing production have aroused concern of their impacts on environmental health. The objective of this study is to ...quantify the number and mass of two most common textile fibers discharged from sequential machine washings to sewers. The number and mass of microfibers released from polyester and cotton textiles in the first wash varied in the range 2.1 × 10
5
to 1.3 × 10
7
and 0.12 to 0.33%
w
/
w
, respectively. Amounts of released microfibers showed a decreasing trend in sequential washes. The annual emission of polyester and cotton microfibers from household washing machines was estimated to be 154,000 (1.0 × 10
14
) and 411,000 kg (4.9 × 10
14
) in Finland (population 5.5 × 10
6
). Due to the high emission values and sorption capacities, the polyester and cotton microfibers may play an important role in the transport and fate of chemical pollutants in the aquatic environment.
During the period from April 2012 to May 2013, 13 newborns (1 to 4 weeks of age) and 1 child in a pediatric hospital ward in Germany were colonized with
producing an extended-spectrum beta-lactamase ...(ESBL) (CTX-M-15). A microbiological source-tracking analysis with human and environmental samples was carried out to identify the source and transmission pathways of the
clone. In addition, different hygienic intervention methods were evaluated.
isolates were detected in the detergent drawer and on the rubber door seal of a domestic washer-extractor machine that was used in the same ward to wash laundry for the newborns, as well as in two sinks. These strains were typed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. The environmental findings were compared with those for the human strains and the isolates detected on clothing. The results from both techniques showed that the strains were identical (sequence type 201 and PFGE type 00531, a clone specific to this hospital and not previously isolated in Germany), emphasizing the washing machine as a reservoir and fomite for the transmission of these multidrug-resistant bacteria. After the washing machine was taken out of use, no further colonizations were detected during the subsequent 4-year period.
Washing machines should be further investigated as possible sites for horizontal gene transfer (ESBL genes) and cross-contamination with clinically important Gram-negative strains. Particularly in the health care sector, the knowledge of possible (re-)contamination of laundry (patients' clothes and staff uniforms) with multidrug-resistant Gram-negative bacteria could help to prevent and to control nosocomial infections. This report describes an outbreak with a single strain of a multidrug-resistant bacterium (
sequence type 201) in a neonatal intensive care unit that was terminated only when the washing machine was removed. In addition, the study implies that changes in washing machine design and processing are required to prevent accumulation of residual water where microbial growth can occur and contaminate clothes.
Fiber release during domestic textile washing is a cause of marine microplastic pollution, but better understanding of the magnitude of the issue and role of fabric care products, appliances and ...washing cycles is needed. Soiled consumer wash loads from U.K. households were found to release a mean of 114 #177; 66.8 ppm (mg microfiber per kg fabric) (n = 79) fibers during typical washing conditions and these were mainly composed of natural fibers. Microfiber release decreased with increasing wash load size and hence decreasing water to fabric ratio, with mean microfiber release from wash loads in the mass range 1.0-3.5 kg (n = 57) found to be 132.4 #177; 68.6 ppm, significantly (p = 3.3 x 10.sup.-8) higher than the 66.3 #177; 27.0 ppm of those in the 3.5-6.0 kg range (n = 22). In further tests with similar soiled consumer wash loads, moving to colder and quicker washing cycles (i.e. 15#176;C for 30 mins, as opposed to 40#176;C for 85 mins) significantly reduced microfiber generation by 30% (p = 0.036) and reduced whiteness loss by 42% (p = 0.000) through reduced dye transfer and soil re-deposition, compared to conventional 40#176;C cycles. In multicycle technical testing, detergent pods were selected for investigation and found to have no impact on microfiber release compared to washing in water alone. Fabric softeners were also found to have no direct impact on microfiber release in testing under both European and North American washing conditions. Extended testing of polyester fleece garments up to a 48-wash cycle history under European conditions found that microfiber release significantly reduced to a consistent low level of 28.7 #177; 10.9 ppm from eight through 64 washes. Emerging North American High-Efficiency top-loading washing machines generated significantly lower microfiber release than traditional top-loading machines, likely due to their lower water fill volumes and hence lower water to fabric ratio, with a 69.7% reduction observed for polyester fleece (n = 32, p = 7.9 x 10.sup.-6) and 37.4% reduction for polyester T-shirt (n = 32, p = 0.0032). These results conclude that consumers can directly reduce the levels of microfibers generated per wash during domestic textile washing by using colder and quicker wash cycles, washing complete (but not overfilled) loads, and (in North America) converting to High-Efficiency washing machines. Moving to colder and quicker cycles will also indirectly reduce microfiber release by extending the lifetime of clothing, leading to fewer new garments being purchased and hence lower incidence of the high microfiber release occurring during the first few washes of a new item.
A new sensorless field-oriented control of direct-drive permanent-magnet synchronous motors based on ldquosliding moderdquo has been studied and applied to domestic washing machine drives. To achieve ...speed control requirements for the application, a novel sliding-mode observer has been developed by applying the technique of feedback of the ldquoequivalent control.rdquo Armed with the developed algorithms, this observer is able to minimize the estimation error of rotor position at low speeds and guarantee fast convergence of the observer at high speeds in the flux-weakening region. As such, this sensorless control is suitable for domestic washing machine drives demanding wide-speed-range operation. The proposed sensorless control algorithms are implemented in a cost-effective digital controller and tested in a selected prototype washing machine. Both computer simulation and experimental results are illustrated for verification.
Microplastic fibres released in synthetic cloth washing have been shown to be a source of microplastics into the environment. The annual emission of polyester fibres from household washing machines ...has earlier been estimated to be 150,000 kg in a country with a population of 5.5 × 10
6
(Finland). The objectives of this study were (1) to quantify the emissions of synthetic textile fibres discharged from five sequential machine washes (fibre number and length) and tumble dryings (fibre mass) and (2) to determine the collection efficiency of two commercial fibre traps. The synthetic fabrics were five types of polyester textiles, one polyamide and one polyacryl. The number of fibres released from the test fabrics in the first wash varied in the range from 1.0 × 10
5
to 6.3 × 10
6
kg
−1
. The fibre lengths showed that the fleece fabrics released, on average, longer fibres than the technical sports t-shirts. The mass of fibres ranged from 10 to 1700 mg/kg w/w in the first drying. Fibre emissions showed a decreasing trend both in sequential washes and dryings. The ratio of the fibre emissions in machine wash to tumble drying varied between the fabrics: the ratio was larger than one to polyester and polyamide technical t-shirts whereas it was much lower to the other tested textiles. GuppyFriend washing bag and Cora Ball trapped 39% and 10% of the polyester fibres discharged in washings, respectively.
Induction motors are an important consumer of electricity. Among induction motors, speed-regulated induction motors have the greatest energy-saving potential. However, motors operating in a very wide ...speed range require a completely different approach than motors operating on a single supply frequency. An example of such motors are the drives of industrial washing machines. The article aimed to present how using field-circuit methods, but above all, analytical methods increase the efficiency of such a motor by changing its design. Thanks to the change of the design and the core material, it was possible to obtain the efficiency of the motor for the frequency of 10 and 20 Hz, meeting the requirements of the IE1 efficiency class specified for the frequency of 50 Hz, while for the frequency of 10 Hz it is 17.9% higher than in the currently produced motor, and for 20 Hz-by 11.1%, while for the frequency of 350 Hz the level of efficiency was corresponding to class IE4. The presented considerations may be the basis for such a procedure for other drives with similar properties. Additionally, an important element of the article is the refinement of the analytical method of determining core losses.
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