Heavy metal elimination from industrial wastewater using natural substrate on pitcher irrigation

Abstract

Combination of pitcher irrigation with drip irrigation system could be resulted in prolonging the secondary treatment period, as it could be an efficient system in which municipal and industrial wastewater can be treated and heavy metals can be reduced. For this purpose, an experiment was conducted with three treatments [clay pitcher included natural zeolite Clinoptilolite (NZ), perlite (P) and vermiculite (V)] which filled half of the volume of a clay pitcher with five replications for each treatments. Beside each tree, one pitcher was placed at 50 cm depth. The soil of each hole was initially sampled, sealed, and transported to the laboratory. The pitchers were irrigated with treated industrial wastewater (from steel factory) 60 times (1500 cc per each irrigation event) over a period of six months. At the end of experiment period, the pitchers were removed and samples were taken from the substrate inside each pitcher and from the soil near the walls and bottoms of the holes. The sealed samples were transported to the laboratory for analyzing heavy metals (Fe, Cd, Cr, Cu, Pb, Mn, and Zn) using an atomic absorption spectrophotometer. The results showed that the used substrates in this experiment have high ability to absorb some heavy metals, especially Pb and Zn which concentration were increased in final value 75 and 80 times compared with initial values, respectively. However, an increase of these two elements in the soil (Zn = 26 and Pb = 71 ppm) nearby the pitcher indicate that the used substrates have limitations in absorption capacity for the heavy metals in high concentration of them in the wastewater. As this is related to their surface area, application of a nano form of the substrates such as nano zeolite might remarkably increase their cation exchange capacity and surface area.

Effect of Arbuscular Mycorrhizal Colonization on Cadmium-Mediated Oxidative Stress in Glycine max (L.) Merr.

“…Thus, Cd appears to be trapped in the interface between soil and roots, suggesting that the hyphal web of R. intraradices in soil could function as a soil-root intermediary, holding Cd inside extraradical hyphae or surrounding Cd by glomalin binding; thus, Cd could never reach the soybean roots despite their high colonization. Furthermore, the vermiculite used in the growth pot culture of soybean has been reported as a substrate that improves the sorption capacity of Al and Fe [34] and HMs such as Cu, Ni, and Cd in water solutions and irrigation systems [35,36]. However, vermiculite has low [35] or middle [34] Cd adsorption capacity compared to other HMs, depending on the pH in the media.…”

Comparison of traditional and modern deficit irrigation techniques in corn cultivation using treated municipal wastewater

“…So, it is more necessary to select the best and new irrigation techniques with the management to improve efficiency of irrigation system (Najafi et al 2016).…”

Study of Zeolite and Vermiculite to Reduce Lead and Cadmium in Wastewater of Alcohol Factory

“…Wen et al (2016) show Zeolite is the best absorbent for Pb, Cu, Zn and Cd removal from wastewater (23). Akkajit P. et al (2013) in research of fractionation of Cd and Zn in Cd-contaminated soils amended by Vinasse, he shows the observed reduction in exchangeable Cd (BCR1) in the amended soils at the 3 % (w/w) application rate, the low total metal concentrations, and the significant amount of essential plant nutrients (N, P, and K) within these waste products highlight the benefits of amending metal-rich soils with them (27) (22). Yilmaz (2016) was used zeolite for remove lead and nickel in synthetically solution.…”

“…Pb, Cd, and Hg, which are typical toxic heavy metals, could be tacked by zeolite. The application in agriculture is suitable due to their ion exchange capability without major changes in structure (22).…”