scholarly journals The Impact of Changing Environmental Conditions on the Retention of Heavy Metals Adsorbed by Pine Bark

2017 ◽  
pp. 278-284
Author(s):  
Oleksandr Khokhotva

Landfills are widely used for the disposal of households' and industrial waste. Liquid landfill effluents contain heavy metals, are toxic to humans and ecosystems and have to be efficiently treated. One treatment option that is becoming popular is the reactive filter technology. The total efficiency of metal removal by a filter media greatly depends not only on adsorption itself, but also on the metal leaching from the adsorbent. The last parameter, in turn, may be dependant on changing environmental conditions since filters are usually located on open air and flow of contaminated water (landfill leachate, runoff water) has the intermittent nature. A filter material may dry, become frozen or stay wet, depending on a season. Previously adsorbed metals can leach from an adsorbent at the next flash of water, coming to water treatment facilities. Among others, pine bark has shown a high capacity to adsorb heavy metals from landfill leachates. In this study, pine bark has been pre-treated with urea-solution in order to increase its stability and adsorption properties. Within leaching experiments using either non-treated or pre-treated bark samples no significant influence of the changing environmental conditions on the extent of metal leaching was observed, though in most cases, metal leaching from wet bark samples exposed to freezing was somewhat higher. Zn leaching was the highest and Cu leaching the lowest for both NTB and UTB samples. The metal leaching from non-treated bark was several-fold higher compared to urea-treated bark. Possible mechanisms of barkurea interactions and reasons for enhanced metals adsorption by urea-modified bark are discussed.

2006 ◽  
Vol 54 (6-7) ◽  
pp. 307-314 ◽  
Author(s):  
B. Béchet ◽  
B. Durin ◽  
M. Legret ◽  
P. Le Cloirec

The thickness of non-saturated zone and physico-chemical conditions are important parameters to assess the impact of infiltration ponds on water resources with respect to heavy metals transfer. As changes in physico-chemical parameters of solutions have a strong impact on the mobility of colloidal phases in sediments and soils, the colloidal facilitated transfer of heavy metals has to be investigated. Therefore, this study focuses on the characterization of runoff, surface and interstitial waters in a retention/infiltration pond collecting runoff waters of a bridge near Nantes. Physico-chemical parameters and chemical analyses were performed on the waters during about one year. The separation of dissolved and colloidal fractions was carried out by filtration and ultrafiltration for one sample of surface and interstitial waters. Until now, the runoff waters were only filtered at 0.45 μm. The comparison of physico-chemical data shows that the minor variations of runoff water parameters are mitigated in basin and in soils but strong variations impact the composition of interstitial waters. High concentrations of zinc, copper and still of lead are measured in runoff. Lead and cadmium seem to be associated to colloidal and particulate fractions while zinc, copper, nickel and chromium are distributed in all fractions.


2021 ◽  
Author(s):  
Jiadong Zhang ◽  
Veljko Prodanovic ◽  
Anna Lintern ◽  
Kefeng Zhang

Abstract Constructed wetlands are a type of green infrastructure commonly used for urban stormwater treatment. Previous studies have shown that the various design characteristics have an influence on the outflow heavy metal concentrations. In this study, we develop a Bayesian linear mixed model (BLMM) and a Bayesian linear regression model (BLRM) to predict the outflow concentrations of heavy metals (Cd, Cu, Pb and Zn) using an inflow concentration (Cin) and five design variables, namely media type, constructed wetland type (CWT), hydraulic retention time, presence of a sedimentation pond (SedP) and wetland-to-catchment area ratio (Ratio). The results show that the BLMM had much better performance, with the mean Nash–Sutcliffe efficiency between 0.51 (Pb) and 0.75 (Cu) in calibration and between 0.28 (Pb) and 0.71 (Zn) in validation. The inflow concentration was found to have significant impacts on the outflow concentration of all heavy metals, while the impacts of other variables on the wetland performance varied across metals, e.g., CWT and SedP showed a positive correlation to Cd and Cu, whereas media and Ratio were negatively correlated with Pb and Zn. Results also show that the 100-fold calibration and validation was superior in identifying the key influential factors.


2020 ◽  
Vol 4 (2) ◽  
pp. 33-25
Author(s):  
Queency P. Padida ◽  
Rolando V. Maningas ◽  
Christian Paul P. dela Cruz ◽  
Lustina P. Lapie ◽  
Nilda S. Alforja

Laguna de Bay is one of the country’s major lakes, providing a third of the fish consumed by Metro Manila’s 16 million residents. It also provides support for agriculture, industry, and hydropower generation, as well as providing a welcome respite for many Filipinos. However, because of the lake’s importance, it is threatened by a variety of issues, including pollution. Heavy metals such as mercury and lead are present in high concentrations in the lake. And these heavy metals may persist in fish, water, air and the human body. As a result, an adsorption technique for heavy metal removal in an aqueous solution was investigated. As an adsorbent, the produced chitosan from crustacean waste shells was employed. The study’s parameters were contact time, adsorbent quantity, and pH. Results showed that 0.5 g of chitosan has a higher absorption rate of 99% in 500 mg/L solutions compared to 1.0 g of chitosan with an adsorption rate of 98%. In terms of contact time, 60 minutes showed almost 100% adsorption rate while 120 minutes was 98%. With increasing pH, the amount of metal adsorption rises. This developed chitosan from crustacean waste shells indicates high capacity as adsorbent materials for heavy metals. As a result, it appears to be a viable material for water treatment.


2016 ◽  
Vol 48 (1) ◽  
pp. 91
Author(s):  
Andrzej Plak ◽  
Jacek Chodorowski ◽  
Irena A. Pidek ◽  
Radosław Dobrowolski

<p>The geochemical analysis of biogenic sediments was used to reconstruct environmental conditions and the impact of human activity from a small mire geo-system in the Sandomierz Basin (Poland SE). Changes in the nature of selected geochemical indicators show a significant impact on the transformation of the mire during the early stages of human activity. It is reflected in the geochemical record by means of a high proportion of heavy metals – cadmium, lead and copper. Evident variability of main geochemical components concentration is also visible in a vertical record of analysed cores. This is a consequence of the sedimentary basin asymmetric configuration and the ensuing variable biogenic sedimentary succession.</p><p> </p><p>Analizy geochemiczne stanową jedną z podstawowych metod badań osadów biogenicznych deponowanych w torfowiskach. W pracy wykorzystano analizę geochemiczną osadów biogenicznych z małego geosystemu torfowiskowego in the Sandomierz Basin (Poland SE) do odtworzenia warunków środowiskowych i wpływu działalności człowieka. Zmiany charakteru wybranych wskaźników geochemicznych zaznaczają znaczący wpływ na transformację torfowiska w najmłodszych fazach działalności człowieka. Rejestrowana jest ona w zapisie geochemicznym poprzez wysoki udział metali ciężkich – kadm, ołów i miedź. Zaznacza się także wyraźna zmienność koncentracji głównych składników geochemicznych w zapisie pionowym analizowanych rdzeni. Jest to konsekwencją asymetrycznej konfiguracji zbiornika sedymentacyjnego i wynikającej z niej zmiennej w czasie biogenicznej sukcesji osadowej.</p>


2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Hartati Oktarina ◽  
Teuku Mukhriza

The increasing and varied use of silver nanoparticles (AgNPs) as antimicrobial on consumer products increases the risk of the nanomaterial release into the environment and potentially harm beneficial microorganisms in soil. Any change in soil microbial composition will lead to soil quality degradation that eventually reduce crop productivity. The negative effect of AgNPs on soil microorganism has been reported by researchers. There are technologies employed to remove heavy metals from soil such as chemical, physical, and biological technique. However, chemical and physical techniques have some disadvantages e.g high cost and partial removal. Therefore, biological technique including the use of microorganisms (bioremediation) become more favourable. The technique is considered as cost effectiveness and environmentally sustainable method. The present paper summarizes the impact of AgNPs on soil microorganisms and the use of microorganisms (bacteria, fungi, algae, and yeast) to eliminate heavy metals pollution in soil.


Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 994 ◽  
Author(s):  
Shen-Yi Chen ◽  
Sheng-Ying Wang

The presence of heavy metals in sewage sludge not only affects the performance of sludge anaerobic digestion process but also restricts the land application of treated sewage sludge. Therefore, a fungi-mediated bioleaching process for simultaneous metal leaching and sludge digestion by Aspergillus niger was developed to treat the sewage sludge containing heavy metals in this study. The effects of two important parameters, sludge solid content and substrate (sucrose) concentration, on the performance of fungal bioleaching were investigated in this study. The results showed that the rate of pH reduction increased with increasing sludge solid contents and sucrose concentrations. In this study, the efficiency of metal removal decreases in the order of Mn > Zn > Ni > Pb. The efficiencies of metal leaching and solid degradation (SS and VSS) were found to be decreased with an increase of sludge solid content and a decrease of sucrose concentration. At 2 days of reaction time, the maximum efficiency of metal solubilization was 95, 56, 21 and 13% for Mn, Zn, Ni and Pb, respectively.


Author(s):  
David Choque-Quispe ◽  
Betsy Suri Ramos-Pacheco ◽  
Carlos Alberto Ligarda-Samanez ◽  
Gloria Inés Barboza-Palomino ◽  
Aydeé Kari-Ferro ◽  
...  

The contamination of water bodies by heavy metals is a critical problem for human health and ecosystems, and it can bioaccumulate in organisms to toxic levels and even lead to the living being’s death. This research aimed to synthesize and characterize a biopolymer with the capacity to remove heavy metals in wastewater, elaborated from potato starch, glycerin, and nopal mucilage. Native potato starch of the Allcca sipas variety was extracted by conventional methods; the mucilage was extracted with ethanol. Four formulations of biopolymers were synthesized at 60 and 70 °C. The solubility, structural characteristics, and adsorption capacity of heavy metals were evaluated. Starch, mucilage, and biopolymers presented predominant functional groups as -OH, -C-O-, -NH-, -C-H-, -C-OH determined by FTIR, allowing to remove up to 50.18% of Al, 56.81% of As, 35.95% of Cr, 37.43% of Hg and 73.22% of Pb determined through an ICPE-OES, for a contact time of 100 minutes at pH 5.0, heavy metal removal and solubility were significantly influenced (p-value < 0.05) by the addition of starch and mucilage. The synthesized biopolymers present a high capacity for heavy metal removal in wastewater.


2020 ◽  
Vol 4 (2) ◽  
pp. 33-35
Author(s):  
Queency P. Padida ◽  
Rolando V. Maningas ◽  
Christian Paul P. dela Cruz ◽  
Lustina P. Lapie ◽  
Nilda S. Alforja

Laguna de Bay is one of the country's major lakes, providing a third of the fish consumed by Metro Manila's 16 million residents. It also provides support for agriculture, industry, and hydropower generation, as well as providing a welcome respite for many Filipinos. However, because of the lake's importance, it is threatened by a variety of issues, including pollution. Heavy metals such as mercury and lead are present in high concentrations in the lake. And these heavy metals may persist in fish, water, air and the human body. As a result, an adsorption technique for heavy metal removal in an aqueous solution was investigated. As an adsorbent, the produced chitosan from crustacean waste shells was employed. The study's parameters were contact time, adsorbent quantity, and pH. Results showed that 0.5 g of chitosan has a higher absorption rate of 99% in 500 mg/L solutions compared to 1.0 g of chitosan with an adsorption rate of 98%. In terms of contact time, 60 minutes showed almost 100% adsorption rate while 120 minutes was 98%. With increasing pH, the amount of metal adsorption rises. This developed chitosan from crustacean waste shells indicates high capacity as adsorbent materials for heavy metals. As a result, it appears to be a viable material for water treatment.


2018 ◽  
Author(s):  
C. Coy ◽  
A.V. Shuravilin ◽  
O.A. Zakharova

Приведены результаты исследований по изучению влияния промышленной технологии возделывания картофеля на развитие, урожайность и качество продукции. Выявлена положительная реакция растений на подкормку K2SO4 в период посадки. Корреляционно-регрессионный анализ урожайности и качества клубней выявил высокую степень достоверности результатов опыта. Содержание нитратов и тяжелых металлов в клубнях было ниже допустимых величин.The results of studies on the impact of industrial technology of potato cultivation on growth, yield and quality of products. There was a positive response of plants to fertilizer K2SO4 in the period of planting. Correlation and regression analysis of yield and quality of tubers revealed a high degree of reliability of the results of experience. The contents of nitrates and heavy metals in tubers was below the permissible values.


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