Washing out heavy metals from contaminated soils from an iron and steel smelting site

Washing is a promising method for separating contaminants bound to the particles of soil ex-situ by chemical mobilization. Laboratory batch washing experi- ments were conducted using deionized water and varying concentrations of oxalic acid, citric acid, tartaric acid, acetic acid, hydrochloric acid and ethylenediaminetetra acetic acid （EDTA） to assess the efficiency of using these chemicals as washing agents and to clean up heavy metals from two heavily polluted soils from an iron and streel smelting site. The toxicity reduction index and remediation costs were analyzed, and the results showed that the soils were polluted with Cd, Pb and Zn. Hydrochloric acid and EDTA were more efficient than the other washing agents in the remediation of the test soils. The maximum total toxicity reduction index showed that 0.5 mol·L^-1 hydro- chloric acid could achieve the remediation with the lowest costs.

Orientational Separation of Sulfur in Petroleum Coke by Alkali Calcining and Reflux Washing

The application of high-sulfur petroleum coke after desulfurization in aluminum electrolysis anodes is an important development trend. However, removing sulfur from high-sulfur petroleum coke is still a significant challenge.This study proposes alkali calcining and reflux washing to examine the impacts of temperature, particle size, the mass ratio of Na_(2)CO_(3) to NaOH, and total sodium addition on the desulfurization efficiency and mechanism. The results show that the desulfurization rate increases with increasing temperature, increasing total sodium content, and decreasing particle size. The addition of alkali can significantly reduce the opening-ring reaction temperature of thiophene and convert organic sulfur into inorganic sulfur(Na_(2)S). Three washing methods were compared, and reflux washing was selected to separate inorganic sulfur(Na_(2)S) from calcined petroleum coke. The sulfur content in petroleum coke decreased from 7.29% to 1.90%, with a desulfurization rate of 80.13% under optimal conditions. The petroleum coke was analyzed before and after desulfurization using X-Ray diffraction(XRD), Scanning Electron Microscopy(SEM), Infrared Spectroscopy(IR), Thermogravimetric Analysis and Differential Scanning Calorimetry(TG-DSC), Gaschromatography-mass Spectrometry(GC-MS). The results show that thiophene and benzothiophene in petroleum coke are decomposed and converted into octane and ethyl cyclohexane. These new observations are expected to provide further understanding and guidance for the utilization of highsulfur petroleum coke.

Discussion on the Treatment of Palmoplantar Keratosis by TCM Soaking and Washing

By combing the mechanism and advantages of traditional Chinese medicine(TCM)soaking and washing and combining TCM syndrome differentiation with western medicine differentiation of diseases,guided by the view that"the principle of external treatment is that of internal treatment",this article discusses the differentiation and treatment ideas of palmoplantar keratosis by TCM soaking and washing,which will provide a reference for clinical treatment.

Improved efficiency and stability of inverse perovskite solar cells via passivation cleaning

Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of research.Yet,their stability remains a barrier to industrial application.This study introduces innovative strategies to enhance the stability of inverted perovskite solar cells.By bulk and surface passivation,defect density is reduced,followed by a"passivation cleaning"using Apacl amino acid salt and isopropyl alcohol to refine film surface quality.Employing X-ray diffraction(XRD),scanning electron microscope(SEM),and atomic force microscopy(AFM),we confirmed that this process effectively neutralizes surface defects and curbs non-radiative recombination,achieving 22.6%efficiency for perovskite solar cells with the composition Cs_(0.15)FA_(0.85)PbI_(3).Crucially,the stability of treated cells in long-term tests has been markedly enhanced,laying groundwork for industrial viability.

Water, Sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es Salaam Region in Tanzania: Status towards Achieving the Sustainable Development Goals and Way Forward

Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections.

Efficient Extraction of Astaxanthin from Phaffia rhodozyma with Polar and Non-polar Solvents after Acid Washing

method of extracting astaxanthin from Phaffia rhodozyma with various solvents after acid washing was investigated. The extraction efficiency was distinctly increased after acid washing of P. rhodozyma cells. When the concentration of HCl was 0.4 mol.L^-1, the highest extraction efficiency of astaxanthin was achieved which was about three times higher than the control. Acetone or benzene as single polar or non-polar solvent was the most ef- fective solvent in our research. With a combination of isopropanol and n-hexane （volume ratio of 2 ： 1）, the maxi- mal extraction efficiency was achieved, approximately 60% higher than that obtained with a single solvent. The liquid-solid ratio and the extracting time were also optimized. Under the optimum extraction conditions, the extraction yield of astaxanthin exceeded 98%.

Effect of Water Washing Pre-treatment on the Properties of Glass-ceramics from Incinerator Fly Ash Using Electronic Arc Furnace

Production of glass-ceramics by sintering the molten slag obtained from electric arc furnace treatment of fly ash was investigated. The effect of washing pretreatment prior to melting the fly ash on the microstructure and properties of the glass-ceramics was examined. The results show that washing pretreatment of fly ash can decrease alkali metal chloride and increase network former in fly ash, which results in the increase of peak crystallization temperature of parent glass and strengthening of properties of bending strength and chemical stability of the glass-ceramics. The optimal heat treatment temperature for parent glass of washed fly ash is 1 173 K, at which the crystalline phase of glass-ceramics is composed of gelignite （Ca2A12SiO7） and akermanite （Ca2MgSi207）. Glass-ceramics produced at optimal heat treatment temperature are excellent in term of the physical and chemical properties and leaching characteristics, indicating attractive potential as substitute of nature materials.

Coal washing scenario in India and future prospects

Coal Washing Exploration in India dates back to 1900s; though, first coking coal washeries in India were installed after independence. At present, most of the coking coal washeries are owned by Public Sector Companies; whereas, most of the non-coking coal washeries are owned by Private Sector. Even after six decades of coal washing practices, there has not been significant development in the coal washing intelligentsia. Indian Coal Washing industry is still dependent on imported equipment, which has been designed to treat coal that is significantly different from Indian coal of drift origin. In this paper, authors have ventured into evolution of Indian Coal Washing Industry （with a focus on coking coal washing sector）, its present condition and future prospect for growth. The paper emphasizes need for developing indigenous solutions to industrial challenges and highlights importance of increased coordination among academia-research institutions and coal industry.

CO_2 Removal from Biogas by Water Washing System

CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/ gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%- 94.2% as liquid/gas ratio increased from 0.14 to 0.50. Increasing pressure （from 0.8 to 1.2 MPa） could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temper- ature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2 MPa with 400 L·h-1 gas flow and 200 L·h-1 water flow, which meets the requirement of CO2 content in natural Ras for vehicle fuel.

Washing effect on properties of Li Ni_(0.8)Co_(0.15)Al_(0.05)O_2 cathode material by ethanol solvent

Different LiNi0.8Co0.15Al0.05O2 cathode materials were washed by ethanol solvent. Inductively coupled plasma atomic emission spectroscopy（ICP-AES）, Fourier transformed infrared（FTIR） spectrum, X-ray diffraction（XRD）, scanning electron microscopy（SEM）, charge-discharge test and electrochemical impedance spectroscopy（EIS） were used to evaluate the elemental contents, structures, morphologies and electrochemical properties of samples. The results show that ethanol washing can remove effectively the synthetic residues LiOH/Li2 O on the freshly-prepared LiNi0.8Co0.15Al0.05O2 and make the sample much more resistant to H2O and CO2, without destroying its bulk structure, surface morphology and electrochemical performances. Moreover, the discharge specific capacity and cycle performance of LiNi0.8Co0.15Al0.05O2 after storage in air with a relative humidity of 80% for three months are improved by immediate ethanol washing.

Application of Electrocoagulation and Electrolysis on the Precipitation of Heavy Metals and Particulate Solids in Washwater from the Soil Washing

Soil washing, ex situ mechanical technique, is one of the few permanent treatment alternatives to remove metal contaminants from soils by employing physical separation based on mineral processing technologies to remove discrete particles or metal-bearing particles and/or chemical extraction based on leaching or dissolving process to extract the metals from the soils into an aqueous solution. However, washwater remained from soil washing process contains discrete particulate particles along with heavy metals as solution phase to be treated separately, as well as this process can produce large amount of sludge that requires further treatment, slow metal precipitation, poor settling, the aggregation of metal precipitates. Electrical treatments including electrocoagulation and electrolysis can be effective in removing these substances from washwater. This paper reviews the theoretical models in applying electrocoagulation and electrolysis to remove heavy metals and discrete particulate particles in washwater by examining and comparing the status of washwater treatment technologies which have been undertaken, mostly in the US and EU for the period 1990-2012.

Plasma-induced graft polymerization on the surface of aramid fabrics with improved omniphobicity and washing durability

Durable superomniphobic surfaces are desirable for their practical applications,including selfcleaning,non-fouling,protective clothing and the separation of liquids.The plasma-induced polymerization of environmentally friendly C6 from a perfluoralkyl methlacrylate copolymer emulsion,AG-E081,was performed and a durable omniphobic fabric was achieved.C6 is an ecological alternative to C8(eight CF2 groups)fluorinated compounds,and it was thereafter successfully incorporated into aramid fabric to achieve a durable superomniphobic surface.The fabric became water and oil repellent with an extremely high water contact angle of 180°.As tested by the water spray AATCC test and hydrocarbon resistance test,the as-prepared fabric gained 100°(ISO 5)and grade number 4 respectively.Furthermore,the fabrics also showed significantly improved washing durability after ten washing cycles.By scanning electron microscopy(SEM),Fourier-transform infrared spectroscopy(FTIR)and x-ray photoelectron spectroscopy(XPS)tests,it is indicated that the durable superomniphobicity can be attributed to the roughness and activation of the aramid surface by the plasma pre-treatment,which induces more adsorption and chemical graft of the C6 copolymer.

Research and Application of the Mathematic Model for the Washing Shrinkage of Woven Fabric

Having analyzed the relationships between washing shrinkage and weaving technique, parameters, material properties of woven fabrics and studied the shrinkage mechanism and its mathematical model of the plain fabric, researchers set up a shrinkage model of the twills and satins and proposed a method for calculating the washing shrinkage based on weaving technique and parameters of fabrics. Shrinkage experiments of silk habotai, silk twill and silk satin fabrics were performed. The results were compared with those of the theoretical computations, and theoretical method is reliable.

Bending and Washing Reliabilities of Screen-Printed UHF RFID Tags Based on Woven Water-Mark Fabric

Compared with bar code and quick response( QR) code in the storage and retailing management of textiles, the ultra-high frequency( UHF) radio frequency identification( RFID) tags have high information capacity as well as reliability in complex environmental conditions. In this study,the UHF RFID tags with perfect integration with textiles are assembled with screen-printed antenna on woven water-mark nylon fabric and Alien UHF integrated circuit( IC), and their reading performance under various washing and bending conditions is evaluated by an RFID reader. The results show that the tags after fifty bending( both arch and sink) cycles of screen-printed antenna still have reading distance more than 5.5 m,and an average reading distance is over 4.0 m after five washing cycles. The experimental results demonstrate that the tag antenna on the water-mark fabric can be manufactured by the screen-printing technology,and a coating process on this fabric facilitates the reading performance and the resistance against complex mechanical impact.

Bronchial Washing to Diagnose Smear-Negative Pulmonary Tuberculosis

Introduction: Bronchoscopy with bronchial washing is useful for the diagnosis of pulmonary tuberculosis (TB) when sputum smears are negative. However, its indication has not been standardized. Therefore, we conducted a retrospective study to assess the diagnostic value of bronchial washing in patients suspected with pulmonary TB. Methodology: A retrospective analysis was performed on patients diagnosed with pulmonary TB in Kosin university gospel hospital, a tertiary hospital with 969 beds in South Korea, from March 2017 to December 2018. We obtained three serial sputum samples for acid-fast bacilli (AFB) smear and culture, and all patients underwent bronchoscopy with bronchial washing for AFB smear and culture. Results: Fifty-six patients were enrolled in the study. Smear-negative pulmonary TB (SNPT) was diagnosed in 42/56 (75%) patients. Among the patients with smear-positive sputum, 14/14 (100%) showed culture-positive sputum, while smear- and culture-positive bronchial washing were seen in 7/14 (50%) and 12/14 (85.7%) patients, respectively. Among the patients with SNPT, 17/42 (40.47%) had culture-negative sputum and were diagnosed using the bronchoscopic washing. Conclusions: For patients with smear-negative sputum, it is necessary to perform bronchoscopic washing to increase the diagnostic rate of pulmonary TB. To control the transmission of pulmonary TB, it is necessary to use a fast and accurate examination method.

Investigation of Different Washing Effects on Physical and Mechanical Properties of Cotton Knitted Garments

This paper deals with three types of washing (enzyme, softener, Silicone) effects on 100% cotton Single Jersey T-shirt, Slub Single Jersey T-shirt, Double Lacoste (5% Lycra) Polo shirt, Single jersey CVC (T-shirt) and PC single Jersey (T-shirt). Typical industrial washing procedures and techniques were followed and then physico-mechanical properties were analyzed under standard condition. It is observed that after washing, weight of each garments has increased from 5% to 36%;stitch length of the constituted fabric has decreased from 1% to 10% approximately;CPI has increased 23% for CVC fabric only for enzyme treatment and for other process it has a little bit or no wash effects. Same effects found for WPI except 100% cotton and Double Lacoste. Shrinkage property both for lengthwise and widthwise remains the same except CVC and Double Lacoste knitted garments and spirality has almost unchanged except 100% cotton and slub fabric. Both the dry and wet rubbing properties have improved after any types of wash except 100% cotton on Silicone wash. Water absorbency property has increased;pH of all the samples is under controlled and lies between 4.5 and 5.0. But there is no significant change of colorfastness to wash and stain after these washing treatments.

Surfactant-Enhanced Washing of Soils Contaminated with Wasted-Automotive Oils and the Quality of the Produced Wastewater

An old automotive industrial site located at Mexico City with many years of operation and contaminated with heavy oil hydrocarbons, particularly spent oils, was assessed for restoration using the surfactant enhanced soil washing (SESW) process. The main goal of this study was to characterize the contaminated soil in terms of TPHs, BTEX, PAHs, and metals contents as well as microbiologically (total heterotrophs and specific degrading microorganisms). We also aimed to determine the surfactant type and concentration to be used in the SESW process for the automotive waste oil contaminated soil. At the end, sixteen kg of contaminated soil were washed and the produced wastewater (approximately 40 L) was characterized in terms of COD, BOD;solids, and other physico-chemical parameters. The soil contained about 14,000 mg of TPH/kg soil (heavy fraction), 0.13 mg/kg of benzo (k) fluoranthene and 0.07 mg/kg of benzo (a) pyrene as well as traces of some metals. Metals concentrations were always under the maximum concentration levels suggested by Mexican regulations. 15 different surfactants were used to identify the one with the capability to achieve the highest TPH removal. Surfactants included 5 anionics, 2 zwitterionic, 5 nonionics and 3 natural gums. Sulfopon 30 at a concentration of 0.5% offered the best surfactant performance. The TPH removals employing the different surfactants were in the range from 38% to 68%, in comparison to the soil washing with water (10% of TPH removal). Once the surfactant was selected, 70 kg of soil were washed and the resulting water contained approximately 1300 mg/L of COD, 385 mg/L of BOD (BOD/COD = 0.29), 122 mg/L of MBAS, and 212 mg/L of oil and greases, among other contaminants.

Washing and Dyeing Wastewater Treatment by Combined Nano Flocculation and Photocatalysis Processes

The research investigated the performance of combined process (flocculation pretreatment-pho- to catalysis). The characteristics of nano flocculation and photocataly were evaluated by simulated dye and surfactant wastewater. In the coagulation and settling period, decolorization rate of five dyes wastewater by nano flocculant was higher than 95%. In the photocatalytic period, degradation of twelve sodium dodecyl benzene sulfonate reached 33%. Washing and dyeing wastewater treated by combined process conformed to the “textile dyeing and finishing industry back to the water quality standard” (FZ/T 01107-2011). The results showed that the combined process was highly advanced treatment for washing and dying wastewater.

Washing Defects and Remedial Actions of Denim Garments and Statistical Review of Denim Sectors in Emerging Economy

This paper aimed to identify the washing defects of denim garments and the remedies for these washing defects of denim garments in Bangladesh.The other purpose of this paper is to explain how such errors are related to the waste,production,and production costs of denim clothing.It also provides a statistical review of the denim sector in Bangladesh as compared to other countries.This paper is conveyed based on theoretical and statistical.It appears washing defects of denim garment,and their remedial actions and reveals the effect of washing defects on wastage,production,and production cost of denim garments.This research paper shows more washing defects of denim garments in Bangladesh.The statistical review displays that Bangladesh is exporting denim products nearly 200 million pieces every year over the world and ranks as the second-largest denim garments exporter after China.By studying this paper,the manufacturer of denim garments in Bangladesh and other countries will be conscious of these defects and able to minimize these defects that will help improve the economy all over the world.

Isolation of Iron Bacteria from Washing Sludge Filters Kolda (Senegal) Water Treatment Station and Study of the Kinetics of Biological Degradation of the Iron (II)

In the present work, the treatment of synthetic waters doped with iron (II) has been studied. The treatment mechanism used in this study is the biological oxidation which consists, in test tubes, of bringing bacteria isolated on Petri dishes into contact with water containing divalent iron (II). These de-ironing bacteria (non-specific bacteria) are used to carry out laboratory biological oxidation experiments on iron (II) under different pH conditions (pH = 3.4 - 3.6, pH = 7.3 - 7.5 and pH = 9.8 - 10) and variable concentration of iron (II). Biological treatment trials included different concentrations of iron during time intervals of a day. Examination of the elimination kinetics of Iron (II) indicates a removal rate of 59.453% for an initial iron concentration in the synthetic solution of 1 mg·L−1 at basic pH (pH = 9.8 - 10). Therefore, the degradation of divalent iron by this method seems to be quite effective, but it should be noted that biological nitrification is impaired by the presence of high iron concentrations above 5 mg·L−1.