How to tackle the stringent sulfate removal requirements in mine water treatment-A review of potential methods.

Sulfate (SO) is a ubiquitous anion in natural waters. It is not considered toxic, but it may be detrimental to freshwater species at elevated concentrations. Mining activities are one significant source of anthropogenic sulfate into natural waters, mainly due to the exposure of sulfide mineral ores to weathering.

Removal of ammonium from municipal wastewater with powdered and granulated metakaolin geopolymer.

Ammonium [Formula: see text] removal from municipal wastewater poses challenges with the commonly used biological processes. Especially at low wastewater temperatures, the process is frequently ineffective and difficult to control. One alternative is to use ion-exchange.

The removal of sulphate from mine water by precipitation as ettringite and the utilisation of the precipitate as a sorbent for arsenate removal.

The aim of this research was to investigate sulphate removal from mine water by precipitation as ettringite (Ca6Al2(SO4)3(OH)12·26H2O) and the utilisation of the precipitate as a sorbent for arsenate removal. The mine water sulphate concentration was reduced by 85-90% from the initial 1400 mg/L during ettringite precipitation depending on the treatment method. The precipitation conditions were also simulated with MINEQL + software, and the computational results were compared with the experimental results.

Sulphate removal over barium-modified blast-furnace-slag geopolymer.

Blast-furnace slag and metakaolin were geopolymerised, modified with barium or treated with a combination of these methods in order to obtain an efficient SO4(2-) sorbent for mine water treatment. Of prepared materials, barium-modified blast-furnace slag geopolymer (Ba-BFS-GP) exhibited the highest SO4(2-) maximum sorption capacity (up to 119mgg(-1)) and it compared also favourably to materials reported in the literature. Therefore, Ba-BFS-GP was selected for further studies and the factors affecting to the sorption efficiency were assessed.

Simultaneous removal of Ni(II), As(III), and Sb(III) from spiked mine effluent with metakaolin and blast-furnace-slag geopolymers.

The mining industry is a major contributor of various toxic metals and metalloids to the aquatic environment. Efficient and economical water treatment methods are therefore of paramount importance. The application of natural or low-cost sorbents has attracted a great deal of interest due to the simplicity of its process and its potential effectiveness.

The effect of magnesium on partial sulphate removal from mine water as gypsum.

The aim of this research was to investigate the effect of magnesium on the removal efficiency of sulphate as gypsum from mine water. The precipitation conditions were simulated with MINEQL + software and the simulation results were compared with the results from laboratory jar test experiments. Both the simulation and the laboratory results showed that magnesium in the mine water was maintaining sulphate in a soluble form as magnesium sulphate (MgSO4) at pH 9.

Acid mine drainage treatment using by-products from quicklime manufacturing as neutralization chemicals.

The aim of this research was to investigate whether by-products from quicklime manufacturing could be used instead of commercial quicklime (CaO) or hydrated lime (Ca(OH)2), which are traditionally used as neutralization chemicals in acid mine drainage treatment. Four by-products were studied and the results were compared with quicklime and hydrated lime. The studied by-products were partly burnt lime stored outdoors, partly burnt lime stored in a silo, kiln dust and a mixture of partly burnt lime stored outdoors and dolomite.

The relationship of pre- and postoperative median and ulnar nerve conduction measures to a self-administered questionnaire in carpal tunnel syndrome.

Study Aims: Following carpal tunnel release (CTR), only very modest correlations have been found between subjective symptoms and function indexes compared to neurophysiological measures. The objective of this study was to evaluate this relationship by comparing the self-administered Boston symptom severity score and function severity score questionnaire against nerve conduction studies (NCS) before and after CTR using two different electrophysiological techniques.

Patients And Methods: Carpal tunnel release was performed in 51 patients (62 hands).

Allosteric transition and binding of small molecule effectors causes curvature change in central β-sheets of selected enzymes.

A quantitative description of allosteric transition remains a significant science challenge. Many allosteric enzymes contain a central β-sheet in their catalytic domain. When an allosteric protein undergoes the transition between T (tense) and R (relaxed) allosteric states, this central β-sheet undergoes a conformational change.

Brainstem size and function at term age in relation to later neurosensory disability in high-risk, preterm infants.

Unlabelled: The aim of this study was to measure brainstem size on magnetic resonance imaging (MRI) scans of high-risk. preterm infants, to assess brainstem function by brainstem auditory-evoked potentials (BAEP) and to determine the predictive value of these measures for the neurosensory outcome. A total of 51 preterm infants (gestational age <34 wk, birthweight <1,500 g) underwent examinations at term age; neuromotor outcome and hearing were followed up until a corrected age of 18 mo.

Prediction of permanent hearing loss in high-risk preterm infants at term age.

Unlabelled: The aim of this series was to assess hearing screenings; auditory brainstem responses (ABR), transient evoked otoacoustic emissions (TEOAE) and free field auditory responses (FF) for the prediction of permanent bilateral hearing loss in high-risk preterm infants at term post-conceptional age. A total of 51 preterm infants (gestational age < 34 weeks, birth weight < 1500 g) underwent examinations at term and hearing, speech and neurological development were followed up until a corrected age of 18 months. Significant hearing defects were verified by broader ABR examinations under sedation and by clinical ward observation including responsiveness to sounds and enhancement of hearing using an amplification device.

Nerve lesions after therapy for childhood acute lymphoblastic leukemia.

Background: The objective of the current study was to use somatosensory evoked potentials (SEP) to detect signs of nerve lesions in the peripheral nerve and in the central nervous system (CNS) after 3 years of treatment for childhood acute lymphoblastic leukemia (ALL).

Methods: The somatosensory potentials evoked by stimulation of the median nerve and posterior tibial nerve were recorded in 31 children with ALL after 3 years of therapy. All patients were examined clinically.