Water Washing Research Articles

Optimization of Growth and Production of Brown Oyster Mushrooms (Pleurotus cystidiosus) through Additional Nutrients of Rice Washing Water and Rice Groats

This study aims to determine the optimization of growth and production of brown oyster mushroom (P. cystidionsus) plants with additional nutrients of rice washing water and to determine the optimization of growth and production of chocolate oyster mushroom (P. cystidionsus) plants through additional nutrients of rice groats. This study used a factorial Complete Randomized Design (RAL) method consisting of two factors, namely, the first factor is rice washing water / leri water (L) and the second factor is rice groats (G). Each treatment is repeated 3 times. Leri water factor consists of 4 levels, namely: A0=0 ml, A1= 30 ml, A2= 50 ml, A3=70 ml. Rice groats factor consists of 4 levels, namely: M0=0 g, M1=60 g, M2= 80 g, M3= 100 g. Data was analyzed using variance analysis (Anova) at 5%. The results showed no effect of rice washing water and rice groats on the growth rate of brown oyster mushroom mycelim, will be at a rice washing water concentration of 70ml / baglog + rice groats 100g / baglog affects the parameters of mushroom stalk height (cm), mushroom hood diameter (cm), mushroom hood thickness (cm), number of mushrooms (clump), and fresh weight of mushrooms / baglog (g).

Factors affecting hand hygiene practice during the COVID-19 pandemic in the Zimbabwean population: a qualitative study

BackgroundPracticing hand hygiene is recommended as one of the key preventive measures for reducing the transmission of COVID-19 and other infectious agents. However, it is often not practiced frequently enough or correctly by the public. We aimed to identify barriers to and facilitators of hand hygiene in the Zimbabwean population during the COVID-19 pandemic.MethodsA qualitative study was conducted with a purposive sample of health workers, village health workers, church leaders, traditional healers, teachers, youth leaders and the general population selected from ten districts across the country from September to October 2022. Semistructured interviews were conducted with 3 key informant interviews per site. In addition, one homogenous focus group discussion was also conducted per site using a focus group discussion guide. The data were recorded on audiotapes, transcribed verbatim, and translated into English. All the analyses were performed manually using thematic analysis.ResultsTwo themes were identified as facilitators of hand hygiene. These include individual factors (knowledge of hand hygiene practices and how they are performed) and access-related factors (access to hand washing infrastructure, soap, and sanitizers). Among the barriers to hand hygiene, four themes were identified: individual factors (knowledge gaps in proper hand washing, lack of conviction about hand hygiene, and habitual behaviour), access-related factors (lack of access to hand washing infrastructure, soap, and sanitizers), safety concerns (concern about the side effects of sanitizers), and sociocultural and religious factors (social customs, cultural beliefs, values, and religious practices).ConclusionDuring public health emergencies, there is a need for people to access uninterrupted, on-premises water supplies to promote compliance with hand hygiene. The provision of clean water and hand washing facilities is critical for vulnerable communities to afford them the opportunity to improve quality of life and facilitate resilience in the event of future pandemics. Community engagement is important for identifying vulnerability factors to provide appropriate mitigatory measures.

Multi enzyme production from mixed untreated agricultural residues applied in enzymatic saccharification of lignocellulosic biomass for biofuel

Lignocellulose recalcitrance essentially dictates high cost and low efficiency of its enzymatic saccharification. The complex lignocellulosic structure is a major obstacle to enzymatic saccharification and green ionic liquid pretreatment methods face difficulty of water washing prior enzymatic hydrolysis. Ionic liquid tolerant lignocellulolytic enzymes overcome the inhibition of enzymes during enzymatic saccharification and eliminated water washing step after pretreatment of lignocellulosic biomass. The cell wall composition cellulose, hemicellulose, and lignin, three main wall polymers of various agricultural residues and food waste lignocellulose substrates also affected the enzyme activities secreted by the B. subtilis strain. This study explores the potential of the halophilic, alkalophilic, and ionic liquid (IL)-tolerant strain Bacillus subtilis BC-001 for the simultaneous production of hydrolytic enzymes essential for lignocellulosic bio-refinery processes. BC-001 produced cellulase, amylase, xylanase, pectinase and protease are 70.41, 87.14, 65.50, 122.55 and 66.48U/mL, respectively under optimized fermentation conditions. Cellulase produced by BC-001 retained more than 80% activity after 72hours in 20% w/w of different ILs tested and enzymes retained more than 68% activities after 12h in 50% w/w ILs. Employing such IL-stable cellulase, enzymatic saccharification is conducted without water washing on rice straw (RS) that has been pretreated with various ILs, including 1-ethyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium chloride, and choline chloride. This research is novel as the study marks the first instance of multi-hydrolytic enzyme production from a novel alkalophilic, halophilic, thermophilic, and IL-tolerant bacterial strain using a mixture of untreated agricultural residues.

Promotion of chloride removal from MSWI fly ash by an accelerated wet-carbonation process to enhance ash recycling in cement manufacture

Chlorides, sulfates, and heavy metals are the three main factors preventing the recycling of municipal solid waste incineration (MSWI) fly ash as an alternative material for cement clinker production, of which chloride plays the main role due to its extremelly hign content in fly ash. This study evaluated three wet-based pretreatment methods (water-washing, CO2-aided washing, and flue gas-aided washing) to remove chlorides using MSWI fly ashes from 13 incineration plants in China. Water washing was suitable for removing Cl- from MSWI fly ash containing a limited amount of less-soluble Cl-containing salts (Ca(OH)Cl, Ca2Al(OH)6(H2O)2Cl, and Ca6(CO3)2(OH)7Cl). However, for fly ash with a significant proportion of these less-soluble Cl-containing salts, injection of CO2/flue gas during washing promoted their decomposition and increased the chloride removal rates by 2–12%. Compared with chloride, the removal rate of sulfate was lower under all treatment scenarios and ranged from 7% to 47%. Therefore, caution should be taken when exploring techniques for the deep removal of chloride from MSWI fly ash, as sulfates may be the limiting factor in fly ash samples with low chloride contents when utilizing the fly ash for cement clinker production. Heavy metals in fly ash were not a limiting factor for any ash samples (either raw ash or treated ash) when utilizing the fly ash for clinker production. However, the dissolution of heavy metals in the washing solution deserves more attention, as a large amount of wastewater will be generated during wet-based pretreatment methods. This study confirmed that CO2/flue gas injection during washing promoted the removal of the less-soluble harmful components of fly ash, expanding the applications of ash materials.

Impact of Washing and Fermentation on the Concentration of Pesticide Residues in Nigerian Staple Foods By IJISRT

The use of pesticides in agriculture is linked to accumulation of toxic compounds in the soil, in food, and its accumulation in animal and human tissues. Pesticide residues are deposits of pesticides that remain on or in agricultural produce after harvest or during storage. This work examined the effects various processing steps on the levels of methoxychlor, dieldrin, p,p’-DDE and α- chlordane residues in common staples; maize, rice, beans and cassava. The treatments administered included cold water washing, hot water washing, and fermentation for 3 and 5 days. The Quick, Effective, Cheap, Easy, Rugged and Safe (QuEChERS) technique was adopted for extraction of pesticide residues while gas chromatography tandem mass spectrometry was used for quantification of the residues in the samples. The processing steps applied had various effects on the level of residues ranging from - 149% to 100% reduction in level of pesticide; in rice processing, washing with hot water had the greatest impact in reducing methoxychlor (55.5-97.1%) and α- chlordane (95.5%). Fermentation for 5 days had the greatest impact in reducing methoxychlor residue from cassava (13.6-26.3%), while fermentation of maize for 3 or 5 days had similar impact in reduction of the level of methoxychlor (35.5-79.5% and 39.1-78.4% respectively) and α-chlordane (100% and 100% respectively). Hot water washing of beans was most effective in eliminating methoxychlor (98.4%), p,p’-DDE (100%), α-chlordane (100%) and dieldrin (100%). Reduction in hazard index was also observed with processing, as a result of reduction in amount of pesticide going into the diet.

Multi-frequency thermosonication washing treatments of fresh-cut lotus root: Effect on the accumulation of phenolics and storage quality characterization evaluation

The effects of thermosonication (TS) washing at varying multi-frequencies in comparison to ultrasonication (US) and water washing (as a control) on the fresh-cut lotus root phenolics accumulation and the storage quality characteristics were explored. The relationships between free phenols (FPs), bound phenols (BPs), total phenolic content (TPC), and total antioxidant capacity were also revealed. Thermosonication increased the free phenols and total phenolic content, with the thermosonication of 20 + 40 + 60 kHz showing the most significant effect, and TS predominantly improved the total antioxidant capacity. Thermosonication promoted phenylalanine ammonia-lyase (PAL) activity and inhibited polyphenol peroxidase (POD) activity. The color analysis showed the thermosonicated samples exhibited the lowest value of ΔE and the browning degree. Thermosonication substantially increased weight loss and firmness, while reducing the levels of malondialdehyde (MDA) and Vitamin C (VC) compared to control. Overall, TS washing can increase the phenolic content of fresh-cut lotus root while preserving its antioxidant capacity and qualitative characteristics.

Insights into the Roles of Surface Functional Groups and Micropores in the Sorption of Ofloxacin on Banana Pseudo-Stem Biochars

In the present study, banana pseudo-stem (BS) was pyrolyzed under anaerobic conditions without any physical or chemical modification. Their properties, as well as their sorption affinity to ofloxacin (OFL), were studied. As a result, oxalates and KCl formed at a relatively low temperature of 300 °C, while bicarbonates generally formed at a pyrolysis temperature above 400 °C. Surface functional groups of BS biochars facilitated OFL sorption mainly via specific interactions including electronic attraction (EA), π–π electron donor–acceptor (π–π EDA) interaction, the ordinary hydrogen bond (OHB), and the negative charge-assisted hydrogen bond ((−)CAHB). Except for (−)CAHB, these interactions all decreased with an elevated pH, resulting in overall decreased OFL sorption. Significant OFL sorption by BS biochars produced at 300 °C, observed even at an alkaline condition was attributed to (−)CAHB. Micropores formed in BS biochar prepared at 500 °C, with a specific surface area as high as 390 m2 g−1 after water washing treatment. However, most micropores could not be accessed by OFL molecules due to the size exclusion effect. Additionally, the inherent K-containing salts may hinder OFL sorption by covering the sorption sites or blocking the inner pores of biochars, as well as releasing OH− into the solution. Thus, BS biochar produced at 300 °C is an excellent sorbent for OFL removal due to its high sorption ability and low energy. Our findings indicate that biochar techniques have potential win–win effects in recycling banana waste with low energy and costs, and simultaneously converting them into promising sorbents for the removal of environmental contaminants.

Effect of Deashing Treatment on Ash Fusion Characteristics of Biochar from Bamboo Shoot Shells.

To investigate the influence of deashing on fusion characteristics, a combined method of water and acid washing with different sequences (water washing followed by acid washing, and acid washing followed by water washing) was used to treat the biochar of bamboo shoot shells (BBSSs). The results show that deashing decreased the K content of the biochar from 50.3% to 1.08% but increased the Si content from 33.48% to 89.15%. The formation of silicates and aluminosilicates from alkali metal oxides with silicon was an inevitable result of ash phase transformation at the high temperatures used to improve the fusion temperature (>1450 °C). The thermochemical behavior of ash mainly occurs at 1000 °C. The deashing treatment significantly reduced the reaction intensity during the high-temperature process. This significantly increased the thermal stability of the ash. The adjustment of the washing sequence had a slight impact on the chemical compositions, but the differences in ash micromorphology were obvious. Deashing treatments with different washing sequences can significantly improve ash fusion properties effectively and reduce the risk of scaling, slagging, and corrosion. This study provides a new and reasonable strategy for the deashing of biochar to commercially utilize bamboo shoot shell resources.

Interfacial Engineering of P2-Type Ni/Mn-Based Layered Oxides by a Facile Water-Washing Method for Superior Sodium-Ion Batteries.

Owing to the strong basicity and reactivity, residual sodium compounds (RSCs) on the surface of Na-based layered oxides for sodium-ion batteries (SIBs) cause the deterioration of the electrochemical performance and processability of the oxide cathode materials. Herein, considering P2-type Na0.66Ni0.26Zn0.07Mn0.67O2 as the model material, the water-washing treatment is proven to be a facile, economic, and highly efficient method to improve the electrochemical performance of P2-type Ni/Mn-based layered oxides. Experimental results show that RSCs on material surfaces can be effectively removed by water washing without causing severe damage to the bulk structure. Notably, water washing triggers the formation of an ultrathin (2-3 nm thick) Na-poor disordered interfacial layer on the surface of Na0.66Ni0.26Zn0.07Mn0.67O2. This layer plays a passivating role in further enhancing the material's resistance to water and reduces the reactivity of the material surface with the electrolyte. These compositional and structural optimizations for P2-type Na0.66Ni0.26Zn0.07Mn0.67O2 effectively suppress the release of gaseous CO2, formation of thick cathode-electrolyte interphase films, and consumption of active Na+, enabling good Na+ transport kinetics during cycling. The water-washed Na0.66Ni0.26Zn0.07Mn0.67O2 exhibits significantly improved cycling stability with a capacity retention of 89.1% at 100 mA g-1 after 100 cycles and rate capability with a discharge capacity of 76.3 mA g-1 at 2000 mA g-1; these values are higher than those of the unwashed Na0.66Ni0.26Zn0.07Mn0.67O2 (83.3%, 71.4 mA h g-1). This work provides fundamental insights into the detrimental effect of RSCs on the electrochemical performance of layered oxides and highlights the importance of regulating interfacial compositions for developing high-performance layered-oxide cathode materials for SIBs.

Investigation of the cyclic separation of dioxins from municipal solid waste incineration fly ash by using fat

It is necessary to detoxify municipal solid waste incineration fly ash (MSWIFA) to facilitate resource utilization. The current research focused on the treatment of heavy metals in MSWIFA which is relatively well-developed, while dioxins (PCDD/Fs) need to be treated with more referable programs. Based on the excellent lipophilicities of dioxins, readily available, nontoxic, harmless, and easily treatable animal fats have been used to separate the dioxins from MSWIFA samples, thereby reducing the toxic equivalence of the MSWIFA. The experimental results indicated that animal fats significantly reduced the toxic equivalence of untreated, water-washed, and acid-washed MSWIFA samples, with reductions in the dioxin toxicity equivalence of up to 70%. Furthermore, in studies of heavy metal leaching, water washing followed by pig fat (FP) separation was identified as the optimal approach for the separation of dioxins from MSWIFA. Under the optimal conditions, the toxicity due to dioxins was reduced by over 70% after separation from MSWIFA with recycled animal fats. The environmental and economic benefits of this treatment option were analyzed on this basis.

Effect of vine leaves processing on Azoxystrobin, Fenazaquin and Indoxacarb residues dissipation: processing factors and consumer safety assessment

The effect of vine leaves processing techniques on Azoxystrobin, Fenazaquin, and Indoxacarb residues was investigated. Residue extraction following field application of pesticides and leaf processing was carried out using the QuEChERS method, with analysis conducted by LC-MS/MS. In dry conservation, Azoxystrobin's half-life was estimated to exceed a year, Fenazaquin's was 18 days, and Indoxacarb's was 142 days. Azoxystrobin had a half-life of 261 days, Fenazaquin had a half-life of 9 days, and Indoxacarb's half-life exceeded a year in brine conservation. It is recommended to use dry conservation because it results in an average 60 % reduction in residue levels for the three pesticides. Boiling water significantly reduced pesticide residues (Azoxystrobin −40.3 %, Indoxacarb –22.4 %, and Fenazaquin −28.8 %). It is recommended to use boiling water for washing, as it shows an average removal rate of approximately 30 %. The health risk assessment indicated that consuming vine leaves posed no health risk for consumers, but overall exposure to residues must be considered.

Undesired films with brilliant whiteness produced from a transparent amorphous polymer solution during room temperature evaporation or water washing

AbstractDuring the use, storage, or cleaning of polyetherimide (PEI) solutions, undesired white films often appear. In this study, equivalent experiments of PEI solutions involving room temperature evaporation and solvent exchange with water are conducted to simulate their air exposure and water washing processes, respectively. Specifically, we focus on investigating the phenomenon and mechanism of white appearance in their films from room temperature evaporation with a cellular‐like porous structure and solvent exchange films that exhibit a finger‐like porous structure. Results obtained from FE‐SEM, UV–Vis spectroscopy, and Datacolor reflectance spectrophotometer indicate that both types of porous structures exhibit long‐range disorderliness, leading to multiple scattering of incident light and high reflectance across the visible light spectrum resulting in a white appearance. Furthermore, due to different structures caused by phase separation, mechanical properties of solvent exchange films are significantly inferior compared with those of films from room temperature evaporation. Finally, we verify the universality of these mechanisms for white film formation in PEI through experiments using PS and PMMA. This study provides insights into efficient utilization of polymer solutions and offers new strategies for biomimetic preparation of white films.Highlights White cellular‐like porous films were prepared by solvent evaporation method. White finger‐like porous films were produced through solvent exchange by water. Multiple scattering caused by above porous structures led to white appearance. Finger‐like porous films with nanosphere as the basic scatter unit had a luster. Universality of both white formation mechanisms was verified by PMMA and PS.

Understanding the Effects of Hydrophobic Particle Densities on Bubble-Liquid Motion and Gangue Entrainment in the RFC’s Reverse Fluidized Bed Through CFD Simulation

ABSTRACT The Reflux Flotation Cell (RFC) developed recently provides great potential in solving the emerging challenges, in terms of low plant capacity and low metal production, faced by the resources industry. However, the bubble-liquid motion and the mechanisms responsible for gangue entrainment in the RFC have not been well studied. In this study, chalcopyrite and coal were chosen as value materials and quartz was chosen as a gangue material, and the flotation of chalcopyrite or coal against quartz was conducted in the RFC. It was found that chalcopyrite flotation produced a much higher quartz recovery than coal flotation despite the same operating conditions employed, which indicated a great effect of hydrophobic particle density on gangue entrainment in the RFC. CFD simulations indicated that a higher density of hydrophobic particles increased the gas holdup in the RFC’s reverse fluidized bed and the boundary of the air phase, which promoted gangue entrainment. Meanwhile, the higher density of hydrophobic particles also inhibited the formation of a liquid recirculation loop in the reverse fluidized bed, weakening the displacement of gangue particles with wash water and resulting in higher gangue entrainment. The findings from this study will provide guidance on how to minimize gangue entrainment in chalcopyrite flotation in the RFC.

Magnesium recovery from ferronickel slag by reaction with sodium hydroxide

Ferronickel (FeNi) slag, as the main solid byproduct of the FeNi industry, has the potential to be utilized other than as roadbed material. To broaden the applications of FeNi slag (such as CO2-capturing materials), there is a need for a treatment that breaks the magnesium silicate bonds and transforms the magnesium into MgO. As an initial study, this research treated FeNi slag by using sodium hydroxide followed by water-washing. The present authors evaluated several alkali treatment variables; such as temperature (523 K and 773 K), time (1–8 h), and mass ratio between FeNi slag and NaOH (1:0.75–1:4). The magnesium in FeNi slag was recovered as MgO. By using a FeNi slag:NaOH mass ratio of 1:2, a temperature of 773 K, and a time of 4 h, 97.34% of the magnesium was recovered, and 83.35% of the silicon was removed. During alkali treatment, the Mg-based compound in FeNi slag undergoes a transformation from MgSiO3 to Mg2SiO4 to MgNa2SiO4 and, finally, to MgO. On the other hand, the Fe-based compound transforms olivine to Fe2O3 to spinel (Fe2MgO4 and Fe3O4) and, finally, to FeNaO2. The alkali treatment process of FeNi slag using NaOH followed by water washing is also known to make the product morphology porous and has a large surface area (11.62 m2/g). In terms of economics, this process will be economical when considering the by-product (Na4SiO4) generated.

The isomorphous substitution of Si(4Al) with P in FAU zeolite and its stabilization effect

It's a dream to make zeolites more stable so as to keep the activity and stability of the catalyst. Phosphorus modification is an effective method, however, the known post-modification predominantly presents as non-framework P, and the P-loss is a big trouble in application. We have discovered that in the reaction of PCl3 or SiCl4 + PCl3 with NaY zeolite, a portion of P enters the framework of the zeolite, forming a PO4-AlO4 structure. Further investigations revealed that P cannot be incorporated into the framework through P for Al isomorphous substitution, but rather through isomorphous substitution with Si(4Al). PCl3 exhibits two effects in reaction: at lower quantities, it mainly undergoes isomorphous substitution with Si(4Al); at higher quantities, it leads to zeolite dealumination generating aluminum vacancies, which disrupt the zeolite framework or promotes Si for Al isomorphous substitution. After hydrothermal aging at 800 °C for 4 h, the stable presence of framework PO4-AlO4 implies that the weakest site Si(4Al) becomes the more stable site P(4Al) in the Y zeolite framework. Compared with the JPY (prepared by impregnating (NH4)2HPO4 solution to high silica Y zeolite) sample, after 10 cycles of hydrothermal and water washing treatment, the P2O5 loss rate of DPY (prepared by SiCl4 + PCl3 with NaY) zeolite ranged from 0.4 % to 3.5 %, significantly lower compared to the range of 18.7 % to 25.9 % observed in the JPY sample. This indicates that in DPY zeolite, the interaction between P and the zeolite is stronger and less prone to loss. Moreover, P is more uniformly distributed on the surface and bulk phase of DPY than JPY sample.

The influence of pH on the efficacy of oxidation-reduction potential (ORP) to predict chlorine disinfection of surrogate bacteria, Escherichia coli O157:H7 and Listeria monocytogenes in oxidant demand free conditions and fresh produce wash water

Oxidation-reduction potential (ORP) is commonly used as a rapid measurement of the antimicrobial potential of free chlorine during industrial fresh produce washing. The current study tested the hypothesis that ORP can act as a “single variable” measurement of bacterial (vegetative and endospores) inactivation effectiveness with free chlorine irrespective of the water pH value. This situation has on occasion been assumed but never confirmed nor disproven. Chlorine-dosed pH 6.5 and 8.5 phosphate buffer solutions were inoculated with Escherichia coli (E. coli), Listeria innocua (L. innocua), or Bacillus subtilis (B. subtilis) endospores. ORP, free chlorine (FC), and log reduction were monitored after 5 s (for E. coli and L. innocua) and up to 30 min (for B. subtilis spores) of disinfection. Logistic and exponential models were developed to describe how bacteria reduction varied as a function of ORP at different pH levels. Validation tests were performed in phosphate buffered pH 6.5 and 8.5 cabbage wash water periodically dosed with FC, cabbage extract and a cocktail of Escherichia coli O157:H7 (E. coli O157:H7) and Listeria monocytogenes (L. monocytogenes). The built logistic and exponential models confirmed that at equal ORP values, the inactivation of the surrogate strains was not consistent across pH 6.5 and pH 8.5, with higher reductions at higher pH. This is the opposite of the well-known free chlorine-controlled bacterial inactivation, where the antibacterial effect is higher at lower pH. The validation test results indicated that in the cabbage wash water, the relationship between disinfection efficiency and ORP was consistent with the oxidant demand free systems. The study suggests that ORP cannot serve as a reliable single variable measurement to predict bacterial disinfection in buffered systems. When using ORP to monitor and control the antibacterial effectiveness of the chlorinated wash water, it is crucial to take into account (and control) the pH.

A fuzzy classification method based on rules learning for shaded and unshaded hotspot faults on photovoltaic modules

Hotspots (HS) reduce the output power (P) of photovoltaic modules (PVMs) and sometimes lead to fires. However, it is difficult to effectively classify and detect HS faults. In this paper, we focus on the classification and detection of Shaded HS and Unshaded HS. HS faults not only occur due to non-uniform illumination and parameter mismatch but due to internal defects as well, such as; low resistance defects of a cell. The Shaded HS can be repaired sometimes by water washing, such as PVMs in the desert, while the Unshaded HS can only be repaired by replacing them. Therefore, to classify and detect such HS faults, we propose a fuzzy classification method based on data-driven rules learning. Firstly, the characteristic performances of Shaded and Unshaded HS PVMs are compared with the performances of normal PVMs. Secondly, the percentage reduction algorithm is presented for extracting three fault indicators to identify such HS faults. Then, a classification method is proposed using a technique called the Mamdani-type Fuzzy logic system, in which the rules are obtained by a process called the “Data-Driven Rule Generation Method”. Finally, a low-resistance HS model is built using Matlab Simulink. The simulation and experiment results show that the proposed method has more classification accuracy for Shaded and Unshaded HS faults.

Sustainable Water Use in a Fruit Processing Plant: Evaluation of Microbiological and Physicochemical Properties of Wash Water after Application of a Modular Water Recovery System

The reuse of wash water in the agri-food industry is in line with sustainability goals through the reduction of the water footprint. Depending on the production process and raw material type, wash waters may exhibit severe biological and physicochemical contamination. The use of traditional methods of chlorine disinfection of water may be linked to the formation of hazardous by-products. The recycling of contaminated water should be supported by the evaluation of physicochemical and microbiological parameters before and after application of a treatment to validate the process. This study aimed to assess physicochemical and microbiological properties of rinse water from a post-harvest processing plant before and after applying an innovative modular water treatment system. The test material was washing water after apple rinsing obtained from a post-harvest processing plant (Northern Poland). The water recovery system included a wash water tank, a sand pre-filter, an ultrafiltration system, and an ozonation tank. No microorganisms were found in the treated water. The physicochemical properties of the water were also improved: pH, conductivity, turbidity, ammonium ion, bromide, and nitrate content. The results indicate that rinse water from the fruit industry may be effectively purified using the tested purification system and reused in production processes.

Industrialized fine physical regeneration process and economic benefit assessment for recycling waste HDPE containers

The production of waste HDPE containers is enormous, and its recycling and utilization is an inevitable trend to achieve sustainable social development. However, the engineering practice of recycling waste HDPE containers is still lacking. This study provides a detailed explanation of the principles of fine recycling for waste HDPE containers, and develops a set of physical regeneration processes. By combining visual recognition assisted sorting, alkali hot water washing, physical sorting, and regranulation processes, high-quality regenerated HDPE particles are prepared. Meanwhile, various real data (sample size 50–100) of the production line and products are tracked, statistically analyzed. The results show that regenerated HDPE particles have good physical properties, the ratio of HDPE particles containing aluminum foil and multicolored impurities are extremely low, and the ratio of HDPE particles containing black spots (d＞0.1 mm) is less than 1.61 × 10−2 wt% (mean). Economic benefit analysis shows that the gross profit of recycled HDPE particles is USD $312.05 per ton. The above conclusions prove the feasibility and progressiveness of this process for the regeneration of waste HDPE containers. Meanwhile, this study provides engineering technical guidance for the large-scale fine recycling and regeneration of waste HDPE containers.

Early warning systems, mobile technology, and cholera aversion: Evidence from rural Bangladesh

In Bangladesh, cholera poses a significant environmental health risk. Yet, information about the severity of cholera risk is limited as risk varies over time and changing weather patterns make historical cholera risk predictions less reliable. In this paper, we examine how households use geographically and temporally personalized cholera risk predictions to inform their beliefs and behaviors related to cholera and its aversion. We estimate how access to a smartphone application containing monthly cholera risk predictions unique to a user’s home location affects households’ beliefs about their cholera risk and their water use and hygiene behaviors. We find that households with access to this application feel more equipped to respond to environmental and health risks and reduce their reliance on surface water for bathing and washing – a common cholera transmission pathway. We do not find that households invest additional resources into drinking water treatment, nor do we find reductions in self-reported cholera incidence. Further, households with a static, non-personalized app containing public health information about cholera exhibit similar patterns of beliefs updating. Taken together, our results suggest that access to risk information can help households make safer water choices, yet improving design and credibility remain important dimensions for increasing application usability.