Fabrication of aluminum beads derived from selectively recovered Al-rich precipitates and their application into defluoridation.

This work introduced a new way of fabricating a granular material with the supply of Al-rich precipitates selectively obtained from acid mine drainage (AMD), and its potential as a promising adsorbent for fluoride (F) was evaluated. Through the selective sequential precipitation (SP) process in the field, Al-rich precipitates with high purity (>81%) were collected at the high recovery rate (>99.8%) as a raw material for adsorbent fabrication.

Water defluorination using granular composite synthesized via hydrothermal treatment of polyaluminum chloride (PAC) sludge.

In this work, we newly synthesized granular composite (GASA) via hydrothermal treatment of polyaluminum chloride (PAC) and subsequently granulation pelleting with starch gel as an organic binder. The resulting composite was characterized with analytic instruments, and the feasibility of utilizing GASA as adsorbent for the removal of fluoride (F) was tested in the batch and column experiments. The characterization results revealed that GASA possessed a spherical/porous framework consisting of aluminosilicate (i.

Zirconia-Assisted Pyrolysis of Coffee Waste in CO Environment for the Simultaneous Production of Fuel Gas and Composite Adsorbent.

This work newly employed monoclinic zirconia (ZrO) as a promoter to improve CO pyrolysis of coffee waste (CW). The CO pyrolysis of CW presented the high level of CO production (14.3 mol%) during two stages of non-isothermal (280 to 700 °C) and isothermal pyrolysis (kept at 700 °C).

A numerical flow analysis using the concept of inflow age for oxidation pond design.

A numerical flow analysis for the design of an oxidation pond was conducted to investigate the optimal flow characteristics. This analysis includes the inflow rate and the shape and depth of the oxidation pond. The total area and maximum depth of the pond were 500 m(2) and 3 m, respectively.

Longevity of organic layers of vertical flow ponds for sulfate reduction in treating mine drainages in South Korea.

This study was carried out to evaluate longevity of available organic materials used for sulfate-reducing bacteria (SRB) activity in vertical flow ponds (VFPs) to treat mine drainage in South Korea. Spent mushroom compost samples (SMC) were tested as substrates in VFPs and analyzed for total organic carbon in VFPs, and were collected to analyze total organic carbon (TOC), T-N, T-P, K, metals and residual cellulose to check the longevity assessment. Chemical analysis revealed that the average contents of Fe, Al and Mn in SMC of VFPs were 19,907, 32,137 and 434 mg/kg, respectively.

Water quality changes of a closed underground coal mine in Korea.

The objective of this study was to assess the changes in mine water quality as an underground mine flooded from July 2005 to October 2008. The effect of air injection with a blower into the water was used to evaluate the potential to convert ferrous to ferric iron and to provide in situ treatment and precipitation. Mine flooding averaged 31 cm/day with a linear shape until November 2007, when it flattened out due to outflow.

Ameliorants to immobilize Cd in rice paddy soils contaminated by abandoned metal mines in Korea.

The cadmium (Cd) content of rice grain grown in metal-contaminated paddy soils near abandoned metal mines in South Korea was found to exceed safety guidelines (0.2 mg Cd kg⁻¹) set by the Korea Food and Drug Administration (KFDA). However, current remediation technologies for heavy metal-contaminated soils have limited application with respect to rice paddy soils.