scholarly journals A Study On The Influence Of Sodium Salt Solution On The Atterberg Limits And Swelling Of Bentonite Clay

2021 ◽  
Vol 23 (10) ◽  
pp. 332-341
Author(s):  
Saurabh Kumar ◽  
◽  
Dr. Prashant Garg ◽  
Amandeep Singh ◽  
◽  
...  

Due to industrialization and subsequent rise in urbanisation, our groundwater system and geoenvironmental reserves are getting degraded due to detrimental effects of industrial wastes discarded off into the geo-environment. Basic components like water, air and soil all get degraded resulting unacceptable loss of their natural virtues like purity, renewability, stability, sustainability and tolerability. Major industrial effluents like salt solutions, chemicals, artificial dyes, heavy metals, pharmaceutical residues and sewages etc., are posing the major problems for the ecosystem and their subparts. Since, bentonite clay has peculiar characteristics of high swelling and high pollutant absorbing capacity along with low hydraulic conductivity, it is used as a geotechnical clay liner. However, the geotechnical parameters of bentonite get affected on interaction with cations present in salt solutions. This investigation was carried out in order to observe the influences of salt solutions on bentonite and the results obtained depicts that the varying salt concentrations have a definite influence on Atterberg limits, swelling of bentonite.

2007 ◽  
Vol 17 (03n04) ◽  
pp. 129-142 ◽  
Author(s):  
S. CHATTERJEE ◽  
B. CHATTOPADHYAY ◽  
S. K. MUKHOPADHYAY ◽  
B. MOHANTA ◽  
M. SUDARSHAN ◽  
...  

Industrial wastes are considered as critical factors for disturbing natural ecosystems. The East Calcutta Wetlands, a Ramsar site in West Bengal, India, receives composite industrial effluents, subsequently bringing various kinds of heavy metals throughout the year. This wastewater is being utilized by the local people for pisciculture. The present investigation was carried out to study 1) elemental distribution various components of the wetland and 2) potentiality of water hyacinth in metal amelioration. Water and sediments were collected from four different spots along a wastewater-carrying canal having a stretch of 40km from the source point to the final confluence with river and from the wastewater fed fishpond. Fish (three common carps viz. Labeo rohita, Cirrhinus mrigala and Oreochromis niloticus) and water hyacinth were collected from fishpond mentioned above. Samples were analyzed by PIXE with 3MeV tandem Pelletron. Cr , which is a known metal contaminant of tannery effluent, was detected along with S , K , Ca , Ti , V , Mn , Fe , Ni , Cu , Zn , As , Br , Rb , Sr , Zr . Variable concentrations of some elements like Ca , Fe , Zn in different fish organs was noted in the experiment. Accumulation of Cr , Cu from the water bodies by water hyacinth suggesting their crucial role in heavy metal amelioration.


Author(s):  
Ghada Heikal

Heavy metals are among the most lethal pollutants of surface water. The main sources of heavy metals are industrial wastes from processes such as mining operations and ore processing, smelter, textile, leather dyeing, coating, metal finishing, chemical manufacturing, refineries, power generation and nuclear fuel processing. The concentration of heavy metals should be reduced to the acceptable levels before discharged into the environment because these are non degradable into nontoxic metals end products and the well known damaging effects of heavy metals on human being and other habitants. Sets of experiments were carried out to examine the ability of (kaolinite and bentonite) to reduce the concentration of chromium and cadmium ions in raw synthetic wastewater using upflow filter respectively. The main parameters were solution pH 2-6, retention time 12-72 hrs, the initial concentration of pollutants 100–500 ppm and filter media height 10.5-42 cm. All data were analyzed by regression analysis model to correlate the different boundary conditions. The highest achieved % removal efficiency of Cr and Cd were 96% and 91% through kaolinite and bentonite clay filter media at pH 6.0 and 5.0 respectively, retention time 24 hr, initial concentration 100 ppm and filter media height 42 cm. The results of regression models indicate that the most influential independent variables in the % removal efficiency of Cr and Cd ions from aqueous solutions using kaolinite and bentonite clay upflow filter pH, retention time and height media filter, which affects positively. Results of the experimental data show that the best empirical correlation achieved the highest fitting of predicted % removal of Cr and Cd using kaolinite and bentonite clay separately that gives the highest value of (R2 = 0.995 and 0.988)respectively.


1992 ◽  
Vol 26 (9-11) ◽  
pp. 2149-2152 ◽  
Author(s):  
A. Grappelli ◽  
L. Campanella ◽  
E. Cardarelli ◽  
F. Mazzei ◽  
M. Cordatore ◽  
...  

Experiments on the real possibility of employing microorganisms to capture inorganic polluting substances, mainly heavy metals from urban and industrial wastes, are running using bacteria biomass. Many strains of Arthrobacter spp., gram-negative bacteria, diffused in the soil also inacondition of environmental stresses, have been proved to be particulary effective in heavy metal capture (Cd, Cr, Pb, Cu, Zn). The active and passive processes in accumulation of metals by bacteria were studied. Our experiments have been done on fluid biomass and on a membrane both for practical use and for an easy recovery.


Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Obulisamy Parthiba Karthikeyan ◽  
Thomas J. Smith ◽  
Shamsudeen Umar Dandare ◽  
Kamaludeen Sara Parwin ◽  
Heetasmin Singh ◽  
...  

AbstractManufacturing and resource industries are the key drivers for economic growth with a huge environmental cost (e.g. discharge of industrial effluents and post-mining substrates). Pollutants from waste streams, either organic or inorganic (e.g. heavy metals), are prone to interact with their physical environment that not only affects the ecosystem health but also the livelihood of local communities. Unlike organic pollutants, heavy metals or trace metals (e.g. chromium, mercury) are non-biodegradable, bioaccumulate through food-web interactions and are likely to have a long-term impact on ecosystem health. Microorganisms provide varied ecosystem services including climate regulation, purification of groundwater, rehabilitation of contaminated sites by detoxifying pollutants. Recent studies have highlighted the potential of methanotrophs, a group of bacteria that can use methane as a sole carbon and energy source, to transform toxic metal (loids) such as chromium, mercury and selenium. In this review, we synthesise recent advances in the role of essential metals (e.g. copper) for methanotroph activity, uptake mechanisms alongside their potential to transform toxic heavy metal (loids). Case studies are presented on chromium, selenium and mercury pollution from the tanneries, coal burning and artisanal gold mining, respectively, which are particular problems in the developing economy that we propose may be suitable for remediation by methanotrophs.


2016 ◽  
Vol 8 (1) ◽  
pp. 174-194 ◽  
Author(s):  
Irina Catianis ◽  
Constantin Ungureanu ◽  
Luca Magagnini ◽  
Elisa Ulazzi ◽  
Tiziana Campisi ◽  
...  

AbstractThe aim of the study was to evaluate the impact of potential pollution sources, mainly from the upstream anthropogenic sources and port-related activities. The in-vestigated area covered a wide range of anthropogenic im-pacts (e.g., industrial wastes, storm water runoff, acciden-tal oil spills, intentional discharges and shipping activities). The quality of water and Sediments was assessed us-ing Standard methods, as physical-chemical parameters, chemistry and biology (microbiology, ecotoxicology) aim-ing to figure the level of pollution and the effect of port-related activities. Seawater quality results agreed generally with environmental Standards. Though, in some samples the concentrations of sulphates (mg/1) and heavy metals (μg/1), as B, As and Se exceeded the recommended lim-its, without posing a serious environmental concern. Most of the surface sediment samples contain critical levels of hydrocarbons (C>12), (mg/kg), polycyclic aromatic hydrocarbons (ng/g) and polychlorobiphenyls (ng/g). For some heavy metals (mg/kg), exchangeable concentrations were found to be very close or above the regulations. The signifi-cance of this study is incontestable taking into account the lack of previous relevant historical data of this area. In this sense, it was possible to indicate, in general, good environmental conditions, despite the industrial and concentrated local port-related activities in the investigated area.


Water Science ◽  
2017 ◽  
Vol 31 (2) ◽  
pp. 189-197 ◽  
Author(s):  
Abhishek Saxena ◽  
Manish Bhardwaj ◽  
Tanu Allen ◽  
Satish Kumar ◽  
Rachana Sahney

1994 ◽  
Vol 30 (10) ◽  
pp. 173-177 ◽  
Author(s):  
Lee Chan-Won ◽  
Kwon Young-Tack

Over the past two decades, the coastal waters of Jinhae Bay have been extensively used by coastal communities and industries for the disposal of domestic and various industrial wastes, therefore increasing the level of pollutants in coastal waters with a subsequent increase in sediments, especially of heavy metals. Specific objectives of this research are to investigate the distribution of heavy metal concentration in biota, to compare the concentrations with those in sediment and water and to relate the bioconcentration to the different heavy metals in biota obtained from several sites. Sixty one percent of heavy metals was found in particulate form during the high runoff season and 32% during the dry season. The behavior of the particulate metals after flowing in to the enclosed coastal sea is an important factor in heavy metal contamination. Copper, lead and chromium contamination of sediment was revealed at several sites. The bioconcentration factors (BCFs) of zinc, cadmium, copper, nickel, chromium and lead by the mussel (Mytilus edulis) were determined as 2,900, 2,814, 807, 423, 228 and 127 in the decreasing order, respectively. The areas located nearest to highly populated city and industries exhibited mussels with the largest accumulation of copper, lead and chromium.


2013 ◽  
Vol 5 (1) ◽  
pp. 132-136 ◽  
Author(s):  
Pawan K. Bharti ◽  
Pawan Kumar ◽  
Vijender Singh

The present paper is aimed towards the assessment of heavy metal contamination of agricultural soil due to irrigation with contaminated ground water affected by textile industrial effluents at Panipat city in India. Samples of ground water and irrigated soils from textile industrial area were analyzed for various heavy metals, viz. Mn, Ni, Fe, Cu, Cd, Pb and Zn, using Atomic Absorption Spectrophotometry. Metal transfer factors from ground water to irrigated agricultural soil and from soil to ground water were calculated for heavy metals. The findings deal with the distribution of heavy metals in ground water of industrial area and irrigated agricultural soil. Transfer factors for heavy metals from effluent to ground water were observed to be 0.436, 1.180, 6.461, 2.401, 2.790, 3.178 and 0.634 for Cd, Cu, Fe, Mn, Ni, Pb and Zn respectively. These were found to be very high from ground water to agriculture soil due to the natural shale value of heavy metals in soil system. Thus, untreated industrial effluents can cause an environmental threat to ground water resources and affects soil quality and agricultural plant productivity.


2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Norasikin Othman ◽  
Chan Kit Hie ◽  
Chiong Tung ◽  
Hanapi Mat ◽  
Masahiro Goto

The recovery of precious metals such as silver from photographic wastes is required in order to save raw materials and to protect the environment from dispersed compound, especially heavy metals. For that matter, several technologies have been used such as precipitation, electrolytic, and ion exchange processes which offer some advantages as well as drawbacks over others. Recently, emulsion liquid membrane extraction has been recognized to be a potential process for industrial wastes treatment and recovery of heavy metals. This process has the ability to selectively separate and rapidly concentrate metals through its very thin layer liquid membrane which has a large interfacial area. An attempt was made to recover silver from liquid photographic wastes using tetramethylthiuram disulfide as a mobile carrier. The important variables affecting the emulsion liquid membrane (ELM) process including residence time, surfactant concentration, carrier concentration, level of agitation and phase ratio between emulsion and feed phase were investigated. The results showed that tetramethylthiuram disulfide is selective towards silver (>80%) compared to other metals in the photographic waste. The highest silver extraction is obtained using 0.05 M tetramethylthiuram disulfide, 3% (w/v) Span 80, 300 rpm stirring speed, 1.0 M thiourea in 0.1 M HCl stripping agent, 1:3 of treat ratio, and toluene as the diluent.


2021 ◽  
Vol 262 ◽  
pp. 02010
Author(s):  
Boris Dzagurov ◽  
Oleg Getokov ◽  
Vladimir Gukezhev ◽  
Taladin Kokov ◽  
Vitaly Vorokov

Based on the results of previous studies on pigs and poultry, in which encouraging results of a significant decrease in the concentration of heavy metals in the body were obtained, respectively, in pork, poultry and eggs, the study provided for the use of the bentonite clay of the Zamankul deposit (RNO-Alania) as an enterosorbent in relation to heavy metals and detoxification of the organism of dairy cows. In order to study the feasibility of using bentonite as an enterosorbent, studies were performed on dairy cows of the Simmental breed in the Kaloyev farm located in st. Zmeyskaya, Kirovsky district of North Ossetia-Alania. To conduct research on the principle of analog pairs, two experimental groups of cows (control and experimental, five cows in each group) of the 3rd and 4th lactation were formed. The experiment lasted for 305 days of lactation from March 2018 to January 2019. Herewith, the control group of cows was fed with a basic diet balanced in all nutritional elements, the experimental livestock, together with the main diet, daily in the composition of the concentrates was injected with crushed bentonite with a particle diameter of 4-6 mm based on the dry matter of the feed (137 g/animal). The study of the concentration of heavy metals (cadmium, lead and zinc) in soil, feed, blood and milk was performed in two periods of lactation (on the 250th and 300th days of lactation). Herewith, an increased content of heavy metals in the soil was established, relative to the MPL: cadmium - 10.1; lead - 7.4; zinc - 9.7 times more, in drinking water: cadmium - 2.5 times; lead - 9.0 times and zinc - 9.7 times more, in feed: cadmium - from 1.7 to 5.3 times; lead - from 1.1 to 1.7; zinc - from 1.0 to 2.5 times the MPL. The inclusion of bentonite to the ration of the animals of the experimental group, in comparison with the control group, in both study periods (250 and 300 days of lactation) contributed to a significant decrease in the concentration of the studied heavy metals in the blood from 17 to 20%, in milk - from 16 to 18 %. The transformation ration values of heavy metals from feed into the body, respectively, into milk, were also lower in the animals of the experimental group, relative to the control.


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