Boron Mine Research Articles

Evaluation of blast-induced ground vibrations in open-pit mines by using adaptive neuro-fuzzy inference systems

This study addresses the effects of rock characteristics and blasting design parameters on blast-induced vibrations in the Kangal open-pit coal mine, the Tulu open-pit boron mine, the Kirka open-pit boron mine, and the TKI Can coal mine fields. Distance (m, R) and maximum charge per delay (kg, W), stemming (m, SB), burden (m, B), and S-wave velocities (m/s, Vs) obtained from in situ field measurements have been chosen as input parameters for the adaptive neuro-fuzzy inference system (ANFIS)-based model in order to predict the peak particle velocity values. In the ANFIS model, 521 blasting data sets obtained from four fields have been used (r 2 = 0.57–0.81). The coefficient of ANFIS model is higher than those of the empirical equation (r 2 = 1). These results show that the ANFIS model to predict PPV values has a considerable advantage when compared with the other prediction models.

Bioremediation of arsenic (As) from mine effluent by a horizontal flow constructed wetland: A case study in largest borax reserve area in over the world, Kırka, Eskişehir

In this study, a horizontal flow constructed wetland (HFCW) planted with Typha angustifolia , was tested to bioremediation potential for arsenic from mine effluent under the natural climatic conditions in largest boron mine reserve area over the world, Kirka (Eskisehir). Briefly, the objective of the present experiment was to investigate arsenic bioremediation capability of wetland system and asses the phytoremediation efficiency of T. angustifolia , selected as a donor plant in this study, with different initial arsenic concentrations. Our results indicated that HFCW has capability to decreased arsenic in mine effluent from 49 µg L -1 to 21.8 µg L -1 in a period of 84 days, suggesting that HFCW could be a reasonable bio-filter option to control arsenic pollution directly from mining effluent in largest borax reserve over the world. Furthermore, we found that arsenic concentration in outflow samples was stably below 10 µg L -1 (drinking water safety limit) with an inflow range from 42.3 to 42.1 arsenic µg L -1 during the first 28 days. Our results also indicated that belowground parts of T.angustifolia accumulate more arsenic from mine effluent compared to aboveground parts during experiment period. Therefore, we suggested that belowground parts of the plants in HFCW play an important role for arsenic bioremediation from mine effluent which origin of Kirka Borax reserve area. In this respect, bioconcentration factor (BCF) for the plants which grown in HFCW was found higher than those of control group. Moreover, results of the present experiment also showed that relatively high level of arsenic retained in the filtration media of HFCW during the experiment period, indicating that filtration media which was used in HFCW has potential to filter arsenic from mine effluent. Consequently, the scientific insight of the present study is to present an innovative, cost effective, and easy operating method for arsenic remediation from mine effluent.

Evaluation of an innovative approach based on prototype engineered wetland to control and manage boron (B) mine effluent pollution.

A major environmental problem associated with boron (B) mining in many parts of the world is B pollution, which can become a point source of B mine effluent pollution to aquatic habitats. In this study, a cost-effective, environment-friendly, and sustainable prototype engineered wetland was evaluated and tested to prevent B mine effluent from spilling into adjoining waterways in the largest B reserve in the world. According to the results, average B concentrations in mine effluent significantly decreased from 17.5 to 5.7mgl(-1) after passing through the prototype with a hydraulic retention time of 14days. The results of the present experiment, in which different doses of B had been introduced into the prototype, also demonstrated that Typha latifolia (selected as donor species in the prototype) showed a good resistance to alterations against B mine effluent loading rates. Moreover, we found that soil enzymes activities gradually decreased with increasing B dosages during the experiment. Boron mass balance model further showed that 60% of total B was stored in the filtration media, and only 7% of B was removed by plant uptake. Consequently, we suggested that application of the prototype in the vicinity of mining site may potentially become an innovative model and integral part of the overall landscape plan of B mine reserve areas worldwide. Graphical Abstract ᅟ.

Phyto-management of boron mine effluent using native macrophytes in mono-culture and poly-culture constructed wetlands

Due to the high solubility of boron (B) compounds in mine effluent and its potential to cause teratogenic effects in the ecological components, the boron mine effluent pollution issues have aroused more and more global attentions, especially drinking waters source where flow through boron-enriched areas. In this study, mono-culture and poly-culture constructed wetlands (CWs) planted with native macrophytes, Typha angustifolia, Juncus gerardii, and Phragmites australis, were tested to phyto-management option of boron mine effluent under the natural climatic conditions in largest boron mine reserve area over the world. According to present results, higher bioconcentration factor (BCF) values were found as 2.095 and 2.828 for Typha angustifolia and J. gerardii growing in CWs during the experiment period. Therefore, T. angustifolia and J. gerardii seem to be the suitable species for phytoremediation of boron mine effluent. Among the native macrophytes, we found that J. gerardii in the mono-culture CW uptake higher than 1000mgkg−1 B from mine effluent during the study period. In this respect, J. gerardii could be a reasonable bio-filter option to control boron pollution directly from mining effluent outlets in boron mine reserve areas all over the world.

Design of Landfill Liner for Boron Mine Waste Water

The purpose of this study is to form the impermeable layer as landfill liner to store boron mine waste water. Boron mine waste water was supplied from Emet (district of Kutahya city, Turkey) Boron Factory. In this study, five different mixtures were used. These mixtures were natural soil, natural soil mixed with Na-bentonite (10%, 20%, 30% and 40%). A miniature landfill tank (240 cm × 120 cm × 60 cm) with six sections was constructed and mixtures were compacted in the container according to the optimum water content. After curing period, 120 liter boron mine waste water was poured into each section and impermeability of mixtures was observed. As a result of observations, it was seen that natural soil was totally inefficient material. Natural soil started leaking on the fifth day and waste water was completely leaked within 27 days. Natural soil mixed Na-bentonite (40%) mixture gave the best result among them. The thickness of impermeable layer formed with natural soil mixed Na-bentonite (40%) can be offered between 40 and 60 cm for the in-situ application.

The Use of Wetlands in Boron (B) Remediation in Turkey

Boron (B) contamination of water sources from mining and other activities have aroused more and more global attention (Wolska and Bryjak, 2013). The known boron (B) mine reserves all over the world are mainly located in Turkey, the United States, China and South America. On the other hand, Turkey contains approximately 70% of total B reserves with 803 million tons, and has supplied the majority of the B used in the world, so that the potential for the contamination of freshwater resources there is high.

A new and effective approach to boron removal by using novel boron-specific fungi isolated from boron mining wastewater.

Boron-resistant fungi were isolated from the wastewater of a boron mine in Turkey. Boron removal efficiencies of Penicillium crustosum and Rhodotorula mucilaginosa were detected in different media compositions. Minimal Salt Medium (MSM) and two different waste media containing molasses (WM-1) or whey + molasses (WM-2) were tested to make this process cost effective when scaled up. Both isolates achieved high boron removal yields at the highest boron concentrations tested in MSM and WM-1. The maximum boron removal yield by P. crustosum was 45.68% at 33.95 mg l(-1) initial boron concentration in MSM, and was 38.97% at 42.76 mg l(-1) boron for R. mucilaginosa, which seemed to offer an economically feasible method of removing boron from the effluents.

Investigation of the effects of blasting design parameters and rock properties on blast-induced ground vibrations

This study addresses the effects of rock characteristics and blasting design parameters on blast-induced vibrations in the Kangal open-pit coal mine, the Tulu open-pit boron mine, and the Kirka open-pit boron mine. In this study, multiple vibration measurements have been conducted, and the related data have been analyzed and evaluated. Several artificial neural network (ANN) and regression models based on the same blasting design parameters, resistivity, and P-wave and S wave velocities of the surrounding rocks have been constructed to estimate the peak particle velocities and the frequencies of related blast-induced vibrations. The data derived from these models and the classical evaluations indicate that ANNs provide more reliable results than the other methods.

Constructed Wetlands as Green Tools for Management of Boron Mine Wastewater

Constructed wetlands are of increasing interest worldwide given that they represent an eco-technological solution to many environmental problems such as wastewater treatment. Turkey possesses approximately 70% of the world's total boron (B) reserves, and B contamination occurs in both natural and cultivated sites throughout Turkey, particularly in the north-west of the country. This study analyzes B removal and plant uptake of B in pilot plots of subsurface horizontal-flow constructed wetlands. Constructed wetlands were vegetated with Typha latifolia (referred to as CW1) and Phragmites australis (referred to as CW2) to treat wastewater from a borax reserve in Turkey-the largest of its type in the world and were assessed under field conditions. The B concentrations of water inflows to the systems were determined to be 10.2, 28.2, 84.6, 232.3, 716.4, and 2019.1 mg l−1. The T. latifolia in the CW1treatment group absorbed a total of 1300 mg kg−1 B, whereas P. australis absorbed 839 mg kg−1. As a result, CW1had an average removal efficiency of 40.7%, while that of CW2was 27.2%. Our results suggest that constructed wetlands are an effective, economic and eco-friendly solution to treating B mine wastewater and controlling the adverse environmental effects of B mining.

The phytoremediation ability of a polyculture constructed wetland to treat boron from mine effluent

This study focuses on describing the ability of a small-scale, subsurface-flow-polyculture-constructed wetland (PCW) to treat boron (B) mine effluent from the world's largest borax mine (Kırka, Turkey) under field conditions. This application is among the first effluent treatment methods of this type in both Turkey and the world. This study represents an important resource on how subsurface-flow-constructed wetlands could be used to treat B mine effluents in the field conditions. To this end, an experimental wetland was vegetated with common reed (Phragmites australis) and cattails (Typha latifolia), and mine effluent was moved through the wetland. The results of the present study show that B concentrations of the mine effluent decreased from 187 to 123mgl−1 (32% removal rate) on average. The T. latifolia individuals absorbed a total of 250mgkg−1 whereas P. australis in the PCW absorbed a total of 38mgkg−1 B during the research period.

Assessment of Lemna gibba L. (duckweed) as a potential ecological indicator for contaminated aquatic ecosystem by boron mine effluent

Duckweeds, as a group, are important early warning indicators for the assessment of contaminated ecosystems due to their propensity to accumulate pollutants. In the present study, we investigated the potential use of Lemna gibba L. (Lemnaceae) as an ecological indicator for boron (B) mine effluent containing B concentration above 10mgl−1. For this purpose, L. gibba fronds were grown for 7 days in simulated water contaminated with B mine effluent. The important note is that this study was carried out in Kırka (Eskişehir, Turkey) B reserve area, which is the largest borax reserve in all over the world, under natural climatic conditions in the field. The results demonstrated that accumulations of B by L. gibba gradually increased based on the initial B concentrations (10, 25, 50, 100, and 150mgl−1) of the mine effluent. B concentration in the dry weight of the plant reached 639mgkg−1 when the minimum initial dosage (10mgl−1) was applied and 2711mgkg−1 when the maximum initial dosage (150mgl−1) was applied during the study. However, significant reductions in their relative growth rates occurred in 50, 100 and 150mgl−1 initial B concentrations. Results suggest that 25mgl−1 B concentration in water seemed to be a sensitive endpoint for L. gibba that could be used as a critical bioindicator level of B contaminated water. Following our data, we also constructed a simple growth model under the climatic conditions in this region of Turkey, but in instructive as a worldwide model. L. gibba is, therefore, suggested to be able to use as both an indicator and a phytoremediation tool because of its high accumulation capacity for B contaminated water.

Isolation of an extremely boron-tolerant strain of Bacillus firmus

A strain of Bacillus firmus (designated strain KC) isolated from a boron (B) mine in California exhibited extreme tolerance to B, provided it was first acclimated at intermediate B supply concentrations. Strain KC tolerated up to 1000 mmol/L B (boric acid-B) and 1800 mmol/L B (sodium tetraborate-B), and attained the greatest growth (as measured by absorbance) at 300 mmol/L B. Despite its extreme tolerance to high B, there was no evidence that it was able to remove significant quantities of B from the growth media, suggesting that strain KC is not likely to be useful for the removal of B from wastewaters in an engineered bioreactor.

Oral colonization and boric acid susceptibility of yeast in boron mineral workers

In this study, we aimed to investigate the effects of boron on in vivo oral yeast colonization in study groups which are exposed to boron dust in different sections of the boron mine. The study was carried out in the boron mining areas of two districts (Eskisehir and Balikesir) of Turkey. We included 184 people working in open quarry and stone milling unit, 144 people working in the factory and 150 people as control group. Specimens were taken from four oral mucosal regions and cultured onto Sabouraud dextrose agar. After incubation for 3 - 7 days at 30°C, the total number of yeast colonies on the plates was considered the relative intensity of carriage, and the total number of yeast colonies on the plates was considered the relative intensity of oral carriage. The susceptibility of Candida spp. to boric acid was investigated. The frequency of Candida colonization in boron intensive area workers was found significantly higher than automatic factory workers and control groups (p = 0.012), there were no difference between automatic factory workers and control groups in point of Candida colonization (p = 0.749). We observed that oral yeast colonization had increased directly proportional with boron powder exposure in boron mine (p = 0.005). Mean minimum inhibitory concentrations (MICs) of boric acid for Boron intensive area, 0.87 - 2.0% for automatic factory and 0.83 - 2.0% for control subjects. We observed that intensive exposure to boron mineral powders was strictly related to oral yeast colonization. Exposure to industrial boron mineral powder may cause important health problems by increasing Candida colonization in oral cavity. It may be useful to do periodical health control in boron mineral workers and population under risk.

Beneficiation of colemanite tailings by attrition and flotation

Boron minerals are generally concentrated using attrition methods followed by screening and classification to remove clay minerals in industrial scale. Physical concentration methods are used in Kestelek Boron Mine for the concentration of colemanite. Because of the inefficient process operation, the tailings containing about 20% B 2O 3 are discarded into the tailings pond. In this study, colemanite tailings sample taken from tailings pond was treated using scrubbing + screening followed by flotation to recover the lost boron. As a result of the experimental studies, a concentrate containing 44.5% B 2O 3 was produced with 68.4% B 2O 3 recovery.

Arsenic Concentrations in the Surface, Well, and Drinking Waters of the Hisarcik, Turkey, Area

ABSTRACT Arsenic is one of the most important water pollutants because of its carcinogenicity. The association between arsenical poisoning and the development of internal malignancies and skin cancer is well known. The U.S. Environmental Protection Agency (USEPA) sets maximum contaminant level goals at zero for carcinogens. In this study are presented groundwater arsenic concentrations in the area of naturally rich boron sources of Turkey. Water samples were collected from the Hisarcik, Turkey, area, which has a large boron mine. An inductively coupled plasma/mass spectrometry method was used to analyze arsenic concentrations in water samples. The arsenic levels in water ranged from no detectable amounts to 3.00 mg As/L (mean: 0.46 ± 0.07SD). This mean As level exceeds by a factor of 10 the USEPA's current Maximum Contaminant Level of 0.05 mgAs/L. Some possible health problems associated with consumption of arsenic-contaminated water are discussed and public health interventions proposed.

Plant distribution and its relationship to extractable boron in naturally-occurring high boron soils in Turkey

Naturally occurring borax reserves exist in dry climates in several parts of the world. Soils associated with these reserves are high in boron (B) and may host distinctive vegetation with high levels of B toxicity tolerance. In this study, three zones of vegetation with increasing distances from the edge of a boron mine were defined at the Kirka Borax Production Plant (Eskisehir, Turkey), one of the richest borax reserves in the world. The zone with the lowest B concentrations (0.1-2 mg/kg) had the highest species diversity (84 species). Species diversity was much lower (28 species) in the intermediate zone that had moderate B levels (10 mg/kg). Only Catapodium rigidum (L.) C. E. Hubbard ex Dony subsp. rigidum var. rigidum (Poaceae) and Gypsophylla perfoliata L. var. perfoliata (Caryophyllaceae) showed resistance to B levels in excess of the accepted toxic levels; these species had the ability to develop and spread in the zone that had the highest B concentration (35 mg/kg).

Environmental boron contamination in waters of Hisarcik area in the Kutahya Province of Turkey

Our aim was to determine boron levels in waters of rich boron mine areas in Turkey. There is a naturally occurring high level of boron in the ground waters of some parts of Turkey. Our study area is Hisarcik village in the Kutahya Province of Turkey which has a large number of boron mines. Boron occurs in combined form, usually borax (Na 2B 4O 7.10H 2O) and colemanite (Ca 2B 6O 11–5H 2O). Water samples were collected from many springs in order to determine boron concentrations and the amount of boron that is exposed to 88 samples from the drinking water (tap water), 37 from ground water and 257 from stream or pond water (surface water). Urine samples taken from 42 residents in this area were analyzed for boron and compared with its levels in drinking waters. The inductively coupled plasma/mass spectrometry (ICP/MS) method was used for the analysis of boron concentrations. Water boron contents at differing locations of this area ranged from 2.05 to 29.00 mg B/l. Mean value of boron was 10.20±4.08 mg B/l. Total urinary boron excretion was ranged from 0.04 to 50.70 mg B/l and mean value was 8.30±10.91 mg B/l. Current information on sources, occurrence, pollution potential and toxicity of environmental boron is discussed.

Adsorption Mechanism of Boric Acid on Chitosan Resin Modified by Saccharides.

This study aims to develop an environmentally-friendly resin for boron recovery. To this end, the adsorption characteristics of boron on chitosan resins chemically modified by saccharides are investigated for the purpose of the removal of boron from a boron mine and the desulfurizing equipment in coal-fired steam power stations, and compared with those of a commercial resin (Duolite ES371). First, chitosan derivatives incorporating saccharides were synthesized by reductive N-alkylation, and the products were crosslinked with ethylene glycol diglycidil ether. The resulting products (SMC resins) were found to exhibit dissolubility in acidic and basic solutions.From the adsorption experiment on the resins (SMC and Duolite resins), it is found that the adsorption mechanism is a complex formation between boron which exists as boric acid or borate in an aqueous solution and the vicinal diol groups of the branched saccharide. The apparent adsorption equilibrium constants of boric acid-diol complex and borate-diol salt complex are determined. The adsorption isotherms of boron correlate well with the Langmuir equation, and the order of the saturated adsorption capacity of boron on SMC resins corresponds to that of the degree of substitution on SMC resins.