Stock Model Based Bottom-up Accounting for Washing Machines: Worldwide Energy, Water and Greenhouse Gas Saving Potentials 2010–2030

Inter-provincial electricity transmissions’ co-benefit of national water savings in China

In the face of increasingly severe pressure on water resources, the theory of virtual water and virtual water trade provides feasible solutions for improving the efficiency of global water use for agricultural products and alleviating the pressure on water resources in water scarce countries or regions. Optimizing the domestic inter-regional trade of virtual water trade of agricultural products can provide information to help for the formulation of China’s water policy. In this study, we will establish scenarios from the two aspects of economy and water resources allocation and utilization, to study the impact of virtual water trade on water saving of agricultural products trade between regions in China. One scenario does not consider water conservation, only economic revenue - net social revenue maximization scenario. Another way to consider water saving is to maximize water saving. With the maximization of net social revenue, 9.6 billion m3 of virtual water had been exported to other regions in the severe drought regions, saving 18.6 billion m3 of water in China. The net social revenue is 9.1 billion RMB. In the scheme of water-saving maximization, virtual water is exported to water rich regions in severe, moderate and mild drought areas, and China had saved 21.5 billion m3 of water. China’s net social revenue is 4 billion RMB. The results show that the optimization of agriculture products domestic inter-regional trade can have a favorable impact on the allocation and utilization of water resources.

Water is essential for life. In Japan we use approximately 83.1 billion m3 of water per year, 87% of which is derived from rivers and lakes and 13% from groundwater. To satisfy our water demand, the Japanese government constructed about 3,000 reservoirs (with bank heights ≥15.0 m) during the latter half of the twentieth century, and these reservoirs produce another 23.8 billion m3 of available water (Ministry of Land, Infrastructure, Transport, and Tourism of Japan 2010; Japan Dam Foundation 2007). In addition, Japan imports large quantities of food estimated to be equivalent to 74.4 billion m3 of virtual water annually (Oki and Kanae 2004).

During laundering, synthetic textiles (polyester, polyamide, etc.) can release small fiber debris with a length of <5 mm. These are a type of microplastics (MPs), usually referred to as microfibers (MFs), which are considered high-concern pollutants due to their continuous and cumulative entrance into the environment. Currently, as far as we know, there are no feasible alternatives to remove them. In this work, four new and sustainable filtering systems are proposed to retain the MFs emitted from domestic washing machines. The filters contain a replaceable cartridge partially filled with recycled low-density polyethylene pellets. The four designed filtering systems of different sizes were tested in a household washing machine determining the retention efficiency of the MFs after several washing cycles. It was found that all four assessed filter arrangements have a good performance for retaining MFs from the washers' effluents. Filter F1 (diameter of 4 cm and a height of 30 cm) started retaining more than 50% of the MFs, at the 10th washing cycle, the retention climbed to 66%, while in the 20th washing cycle, its retention was greater than 80%. MFs retention was higher for filter F2 (diameter of 6.3 cm and a height of 41 cm), achieving a performance greater than 90% in the 20th washing cycle. Filter F3 was arranged by turning the F1 model flow upside down and the retention efficiency is higher compared with filter F1 values, reaching a retention efficiency of almost 100% in the 15th washing cycle. Finally, filter F4 arrangement was developed using the existing washing machine filter, obtaining better performance than the F1 and F2 filters, reaching efficiencies higher than 90% at the 20th washing cycle. In summary, depending on the arrangement, the microfiber retention efficiency was estimated between 52% and 86% in the 1st washing cycle and up to 83% to 99% in the 20th. Additionally, all arrangements demonstrated that the cartridges may last for more than 30 washing cycles before needing to be replaced.

It is becoming increasingly important to put freshwater issues in a global context. Local water depletion and pollution are often closely tied to the structure of the global economy. With increasing trade between nations and continents, water is more frequently used to produce exported goods. International trade in commodities implies long-distance transfers of water in virtual form, where virtual water is understood as the volume of water that has been used to produce a commodity and that is thus virtually embedded in it. Knowledge about the virtual-water flows entering and leaving a country can cast a completely new light on the actual water scarcity of a country. For example, Jordan imports about 5 to 7 billion m3 of virtual water per year, which is in sharp contrast with the 1 billion m3 of water withdrawn annually from domestic water sources. This means that people in Jordan apparently survive owing to the import of water-intensive commodities from elsewhere, for example the USA.

Modern, mainly sustainability-driven trends, such as low-temperature washing or bleach-free liquid detergents, facilitate microbial survival of the laundry processes. Favourable growth conditions like humidity, warmth and sufficient nutrients also contribute to microbial colonization of washing machines. Such colonization might lead to negatively perceived staining, corrosion of washing machine parts and surfaces, as well as machine and laundry malodour. In this study, we characterized the bacterial community of 13 domestic washing machines at four different sampling sites (detergent drawer, door seal, sump and fibres collected from the washing solution) using 16S rRNA gene pyrosequencing and statistically analysed associations with environmental and user-dependent factors. Across 50 investigated samples, the bacterial community turned out to be significantly site-dependent with the highest alpha diversity found inside the detergent drawer, followed by sump, textile fibres isolated from the washing solution, and door seal. Surprisingly, out of all other investigated factors only the monthly number of wash cycles at temperatures ≥ 60 °C showed a significant influence on the community structure. A higher number of hot wash cycles per month increased microbial diversity, especially inside the detergent drawer. Potential reasons and the hygienic relevance of this finding need to be assessed in future studies.

Microfibers are thread-like structures shorter than 5 mm and have natural, semisynthetic, or synthetic origins. These micropollutants are ubiquitous and are emerging in the environment, living organisms, and food sources. Textile laundering is a prominent source of microfibers, but limited research has been conducted on microfiber pollution from domestic washing machines in emerging economies such as India, where consumption and production rates are exorbitantly high. This study aimed to assess the abundance and size distribution of microfibers from the effluent of a semiautomatic domestic washing machine using three categories of "not-new" textiles: cotton, blended, and synthetic under "with" and "without" detergent conditions. Although most Indians still rely on hand washing, this study focused on washing machines due to their increasing use in India driven by improving socioeconomic factors. This study also developed annual emission estimation and forecasting models for India to understand pollution trends. The results revealed that microfibers were highly abundant in washing machine effluent, with a mean abundance of cotton, blended, and synthetic in "with detergent" conditions of 6476.67, 3766.67, and 8645/L, respectively, whereas in "without detergent," it was lower. All identified microfibers were divided into five size classes. The study also found that powdered detergent increased the abundance and emission of tiny fibers. The overall annual emissions estimate was 1.23 × 1011 microfibers, with cotton, synthetic, and blended categories accounting for 2.11 × 1010, 1.40 × 1010, and 6.15 × 109 microfibers, respectively. Time-series-based future estimates (autoregressive integrated moving average [ARIMA] and error-trend-seasonality [ETS]) showed an alarming increase in microfiber emissions, with forecasted annual emission reaching 1.90 × 1011 by 2030. Synthetic and cotton textiles are the most significant contributors to microfiber pollution. This study emphasized the urgent need to address the issue of microfiber pollution caused by washing machine laundering in developing countries, such as India, where sociodemographic factors intensify the problem. Integr Environ Assess Manag 2024;20:2116-2127. © 2024 SETAC.

To investigate the prevalence of β-lactamase genes in domestic washing machines and dishwashers, and the decontamination efficacy of laundering. For the first investigation, swab samples from washing machines (n=29) and dishwashers (n=24) were analysed by real-time quantitative PCR to detect genes encoding β-lactamases. To test the impact of laundering on resistant bacteria, cotton test swatches were artificially contaminated with susceptible and resistant strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus within a second investigation. They were washed in a domestic washing machine with or without activated oxygen bleach (AOB)-containing detergent at 20-50°C. β-Lactamase genes (most commonly of the AmpC- and OXA-type) were detected in 79% of the washing machines and in 96% of the dishwashers and Pseudomonadaceae dominated the microbiota. The level of bacterial reduction after laundering was ≥80% for all Ps.aeruginosa and Kl.pneumoniae strains, while it was only 37-61% for the methicillin-resistant Staph.aureus outbreak strain. In general, the reduction was tendentially higher for susceptible bacteria than for the resistant outbreak strains, especially for Staph.aureus. β-Lactamase genes seem to be frequently present in domestic appliances and may pose a potential risk for cross-contamination and horizontal transfer of genes encoding resistance against clinically important β-lactams. In general, higher temperatures and the use of AOB can improve the reduction of antibiotic-resistant bacteria, including Staph.aureus which appears to be less susceptible to the decontamination effect of laundering. Data on the presence of antibiotic-resistant bacteria in the domestic environment are limited. This study suggests that β-lactamase genes in washing machines and dishwashers are frequent, and that antibiotic-resistant strains are generally more resistant to the used washing conditions.

Sustainability is a guiding principle for a responsible, future‐oriented 21st century lifestyle and this already begins in private households with the daily household tasks. Approximately 25% of an average household's electricity consumption is required to do the laundry and dishwashing – 5% alone is for washing clothes with a corresponding energy consumption of 6 billion kilowatt hours. In addition, 600 000 tonnes of detergent and 330 million cubic metres of water are used for textile care in Germany. These figures provide the rationale for the scientific study of current practices of using washing machines and for a resulting estimate of the latent energy‐saving potential in German households.In the context of the in‐home study presented here, 236 private households throughout Germany were studied with respect to their washing practices and existing knowledge about topics on the sustainable, energy‐saving use of their washing machines. Overall, across all households 2867 wash cycles were individually recorded and subsequently analysed over a 4‐week period.The results of this study show that washing machines tend to be underloaded, and therefore maximum loading of the machines could lead to a reduction of wash cycles per household. With respect to detergent dosage, it was determined that the consumer does not adjust the dosage to the textile type, load size, soil level and/or water hardness, and this can lead to under‐ or overdosing depending on prevailing conditions. Finally, the selection of the wash temperature showed a 90°C/95°C programme was only chosen in 2.3% of all recorded wash cycles, however, every fourth cycle was completed at 60°C. Therefore, adjusting the load size and detergent dosage as well as selecting the right wash temperature are key themes to be taken into account in future consumer communication about energy‐saving households.

The dependence of the domestic washing machine on electricity makes it a potential source of an electric shock that can therefore lead to a burn. The aim of this report is to present a typical case of a washing machine burn and analyse their frequency and circumstances. Using a database, patients who had sustained a burn from a washing machine in a 2.8 year period were identified and the case notes obtained for review. Washing machine burns accounted for 12% of all electrical burns and 22% of all electrical domestic burns. All patients were males who had been attempting to repair a faulty machine. Six of the ten patients required surgical treatment. Despite numerous safety features, washing machines are a common cause of electrical burn, and methods of prevention of such injury need to be addressed.

The article examines the assessment of the state and problems of irrigation water use in the republic in the past and in the near future. A comparative analysis of the state of water resources use for the period of the last 30 years from 1989 to 2019 was carried out. According to the estimates, own water withdrawal for 5 years (2014 / 15-2018/19) shows that an average of 53.2 billion m3 were used for irrigation, including 50.5 billion m3 from rivers. At present (2018-2019), an average of 57.06 billion m3 of water is taken for irrigation of 4.289 million hectares of land, against 63.02 billion m3 approved in 1989. At the same time, the actual water consumption amounted to 48.9 billion m3. Specific water consumption (in the years of average water content) in the Amudarya river basin is 12.5 thousand m3/ha, in the Syrdarya basin - 10.4 thousand m3/ha. Forecast calculations show that there is a tendency to reduce water from rivers to agriculture by an average of 0.104 billion m3/year, with an increase in other sectors from 11.53% (communal and household sector) to 100% (fisheries). The volume of discharges into CDS is decreasing due to the use of collector-drainage waters throughout the region, while specific water consumption has increased to 11.50 thousand m3/ha, i.e. by 450 m3/ha or 28.1%. The reasons for the lack of water for irrigating agricultural crops during the period of vegetative irrigation are stated. The issues of water saving and ways of transition to modern technologies for the use of surface and ground waters, redistribution of water and solutions for the interstate use of river resources are touched upon.

The influence of laundry washing parameters on the release of microfibers (MF) from polyester textiles was studied. These fibers are an important type of microplastic pollution. However, the factors which affect MF release during laundry are poorly understood and more rigorous methods for quantifying this release are needed. A novel method was therefore developed using a tergotometer with eight 1000 mL washing vessels and the CIELab color space measure of lightness (L*). L* was related to the mass of released MFs by creating a calibration curve to quantify the amounts of MFs released from textiles during washing. This method was used to investigate the effect of water-volume, agitation, temperature, and duration of the wash on MF release. Counterintuitively, increased water-volume, characteristic of European "delicate" cycles, resulted in the greatest release of MFs. Full-scale testing was then carried out using domestic washing machines with real consumer cycles to determine the effect of cycle type on MF release. In the first wash, delicate wash cycles released 800 000 more MFs (94 mg/kg) per wash than a lower water-volume standard wash and also increased MF release in subsequent washing cycles (P < 0.05). These results indicate that a high water-volume-to-fabric ratio is the most influential factor for MF release, rather than agitation as previously thought. Therefore, consumers can reduce MF release by avoiding high water-volume washes (delicate cycles), transitioning to appliances that use a lower water-volume (North American high-efficiency washing machines), and ensuring that full wash loads are used.

Microfiber (MFs), are classified as secondary microplastic pollutants with diameter less than 10 µm, mainly released from the laundering of synthetic fabric. Investigations confirmed the universal presence of these fragments throughout the atmosphere including air water and soil. Tiny plastic fibers are the major source of this type of pollutant. Microfiber released by domestic laundering processes of synthetic fabric has recently been detected as the prime source of microfiber pollution in the aquatic environment. However, it is vital to understand the contribution of the synthetic clothes laundering to this environmental problem. Current study mainly focuses on the quantification of data about the release of microplastics, and to identify possible influences of textile characteristics on the release. Washing trials were performed using daily use synthetic garments in the household washing machine in order to record the influence of the washing parameters on the quantity of micro fleeces released. These tiny particles are discharged into the marine environment each year from a variety of sources, of which approximately 700,000 micro fragments are released and 1900 particles from one piece of garment. It can be predicted that, till date, 1.5 million trillion of MF pollutants are currently gathered in the ocean discharged by principal microfiber contributing countries. Domestic washing machines, unable to filter tiny fibers; hence, they can be easily escaped through the outlet to the river and oceans via domestic drainage. Synthetic microfibers are harmful as they are polluting the whole food chain when these pollutants are ingested by smaller aquatic organisms inadvertently. Advancement in the microscopic and spectroscopic techniques is employed for the quick detection of microfleece pollutant in various aquatic systems. Although few and technology with advanced density separation and centrifugation were developed to combat this pollution. However it was scientifically investigated that none of this method and product can filter MFs so competently. Meticulous research in this field is necessary and pre requisite for developing a technique for recycling of these pollutants and sustainable management, which may diminish the pollution level of the water bodies. Future research should primarily aim at developing novel techniques as a solution to this problem. In this present work, primarily the washing machine effluents samples were collected from 5 different house hold regions of Bhubaneswar city, from Odisha state of India. Physiochemical parameters such as pH, Total dissolved solid, Total suspended solid of the collected grey water samples were measured to observe the variation. Morphological feature of the collected microfiber particles such as texture, colour, number and weight were measured. Around 500–520 numbers of visible fiber fleeces were present in 1 L of effluent sample, having biomass 3 mg/L approximately. Dominant presence of deep-red, black and blue coloured microfibers having fiber length 1–2.5 cm was observed. Abundant presence of polyester fiber groups is confirmed through hit description image and peaks 1240.03–2917.38 obtained from FTIR (Fourier transform infrared spectroscopy) analysis.KeywordsWashing machineWaste waterSynthetic microfiberPollutionTreatment

5501792 Energy and water saving laundry system

This article focuses on developing a methodology which can be used to estimate the concentration of dyestuff released from textiles during domestic laundering, so that further studies involving decolorization of the wastewater from domestic washing machine can be conducted in an attempt to develop eco-friendly domestic washing processes. Due to the complexity of the problem, an approach was adopted so that, as an initial step, synthetic red and blue reactive dye solutions were prepared as representative wastewater solutions using Reactive Red 195 and Reactive Blue 19 dyestuffs for the estimation of dye concentration. This was followed by an experimental work consisting of washing tests involving the calculation of dye concentration in the wastewater obtained from domestic washing machine as well as tergotometer as a machine simulator. For this part of the work, dyed cotton plain jersey fabric samples were used to obtain wastewater solutions. All the dye solutions and the wastewater samples were measured with VIS spectrophotometer, and the maximum absorbance values were obtained at relevant wavelengths. Although the characteristics of absorbance spectra of synthetic and wastewater solutions were very different, the maximum absorbance values of both solutions overlapped at relevant wavelengths. The concentration of the dyestuff was calculated from the absorbance values measured at 540 and 592 nm for the red and blue, respectively. The statistical analysis of the data suggested that tergotometer can be used as a domestic washing machine simulator. Moreover, the regression analysis done for the dyestuff concentration under discussion revealed that the most significant factor was the washing step (main wash or rinsing) (89.5%) followed by color (red or blue) (3.4%) and washing device (washing machine or tergotometer) (1.5%).