Attrition scrubbing was used to remediate lead contaminated-site soil, and the main purpose was to remove fine particles and lead contaminants from the surface of sand. The optimal parameters of attrition scrubbing were determined by orthogonal experiment, and three soil samples with different lead concentration were subjected to attrition scrubbing experiments. The results showed that the optimal scrubbing parameters were: a solid ratio of 70% dry matter, a temperature of 25 degrees C, an attrition time of 30 min, and an attrition speed of 1200 r x min(-1). Before attrition scrubbing, the screening and analysis of soil showed that in all three soil samples, lead was mainly enriched on sand and fine particles, and the distribution of lead was highly correlated to the organic matter. After attrition scrubbing, the washing efficiency of the original state lead contaminated sand soil in triplicates was 67.61%, 31.71% and 41.01%, respectively, which indicates that attrition scrubbing can remove part of the fine soil and lead contaminants from the surface of sand, to accomplish the purpose of pollutants enrichment. Scanning electron microscopy (SEM) analysis showed that the sand surface became smooth after attrition scrubbing. The results above show that attrition scrubbing has a good washing effect for the remediation of lead contaminated sand soil.
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Pan Afr Med J
December 2020
Federal Ministry of Health, Addis Ababa, Ethiopia.
Introduction: preventable mortality from complications which arise during pregnancy and childbirth continue to claim more than a quarter of million women´s lives every year, almost all in low- and middle-income countries. However, lifesaving emergency obstetric services, including caesarean section (CS), significantly contribute to prevention of maternal and newborn mortality and morbidity. Between 2009 and 2013, a task shifting intervention to train caesarean section (CS) teams involving 41 CS surgeons, 35 anesthetic nurses and 36 scrub nurses was implemented in 13 hospitals in southern Ethiopia.
View Article and Find Full Text PDFChemosphere
March 2020
School of Minerals Processing and Bioengineering, Central South University, Changsha, Hunan, 410083, China; Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-Containing Mineral Resources, Central South University, Changsha, 410083, China.
The comprehensive recovery of iron and titanium resources from early tailings were systematically attempted from fundamental work to industrial application. Geochemical characterization of the tailings was first conducted, followed by the iron recovery and titanium recovery. Iron recovery was mainly achieved through a series of magnetic separation, and titanium recovery was on the combination of magnetic pre-concentration and flotation separation.
View Article and Find Full Text PDFWaste Manag
June 2019
Institut National de la Recherche Scientifique (Centre Eau Terre Environnement), Université du Québec, 490 rue de la Couronne, Québec, QC G1K 9A9, Canada. Electronic address:
Environmental legislation is forcing industrialized countries to rehabilitate contaminated lands. Expensive solutions are available to treat soils contaminated by metals (e.g.
View Article and Find Full Text PDFEnviron Technol
August 2016
a Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Université du Québec, Québec , Canada.
Three soils polluted by municipal solid waste (MSW) incineration residues and containing various concentrations of Cu, Pb, Sb, Sn and Zn were treated using magnetism, gravity separation (jig and shaking table) and flotation/leaching. The process removed between 18% and 39% of the contaminants present in soil 1, between 31% and 53% of the contaminants present in soil 2 and between 42% and 56% of the contaminants present in soil 3. Polycyclic aromatic hydrocarbons were present only in soil 3, and the process removed 64% of its PAHs total content.
View Article and Find Full Text PDFCochrane Database Syst Rev
September 2014
Department of Obstetrics and Gynaecology, Faculty of Medicine, Universitas Gadjah Mada, DR.Sardjito Hospital, Jl. Kesehatan No.1, Sekip, Yogyakarta, Daerah Istimewa Yogyakarta, Indonesia, 55281.
Background: The risk of maternal mortality and morbidity (particularly postoperative infection) is higher for caesarean section than for vaginal birth. With the increasing rate of caesarean section, it is important that the risks to the mother are minimised as far as possible. This review focuses on different forms and methods for preoperative skin preparation to prevent infection.
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