Quarry Plant Research Articles

Efficacy of Antivibration Gloves When Used with Electric Hammers of about 10 kg for Chiseling Limestone Rocks

The ISO Standard 10819:2013 defines the method for evaluating the performances of antivibration (AV) gloves, but when used in real fields, the protection can be dissimilar to that labeled. This paper investigates the transmissibility, at the palm level, of three different types of AV gloves (air, gel, neoprene) and an ordinary leather glove, during the use of four similar electric hammers (average weight of 10 kg, and average impact energy of 18 J), in a limestone quarry plant. As the average triaxial transmissibility for all the hammers, results show very limited benefits in reducing the vibration (6%), with no significative differences among the different gloves. The working leather glove, instead, shows a transmissibility quite equal to the unit. Anyway, results can be different for the same glove when used among the different hammers, providing in some cases 19% of protection. Some differences can be found regarding the transmissibility through the three main axes for the same type of glove: the glove in gel seems to perform better in shear than in compression. The transmissibility in compression is around 20% higher than that provided by the manufacturers of the certified gloves. The usage of specific excitation curves during laboratory tests could help in providing a more accurate estimation of the transmissibility of the gloves when used with a specific tool.

Effect of quarry activities on selected biological resources around quarry site within Onigambari forest plantation, Oyo State, Nigeria.

Quarry activities are creating diverse stress on biological resources in the rural areas where most of them are located globally. In this study, the effect of quarry activities on elephant grass (Pennisetum purpureum) leaves and soils around Onigambari Forest Reserve, Oyo State, Nigeria, were investigated. Soil and samples of elephant grass (Pennisetum purpureum) leaves were collected from two different distances from the quarry plant. Samples used as control were collected within the boundary of Cocoa Research Institute of Nigeria (CRIN), Oyo State, Nigeria estate. Samples were analysed using proton-induced X-ray emission, to determine the elements. The physiochemical parameters were also analysed in both soil and leaves samples. The mean concentration of the elements in the soil sample from Site 1 was higher in Mg, Cl, Ca, Ti, Cr, Mn, Fe, Zn and Zr than Site 2 and the control site. While in leaves, similar trend was observed. Cd and Ag were highly enriched.

Ecological and geological determination of the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine)

In our time, a very urgent problem is the cessation of negative impacts on the environment and the return to the practical use of the territories of devastated lands. In this regard, it is important to find out the basic laws of primary soil formation in the area of these man-made neoplasms. The initial soil formation conditions were analyzed on 19 experimental sites which represent the main varieties of devastated land in the Kryvyi Rih Iron Mining and Metallurgical District (Central Ukraine): (i) waste rock dumps of old iron mines (old name “Forges”), (ii) tailing storage facility of underground iron mines, (iii) waste rock dumps of the Iron Ore Mining and Dressing Plant, (iv) waste rock dumps of the Granite Quarry Plant. It was established that on the devastated lands in Kryvyi Rih District, the initial soil formation occurs in very difficult conditions. Therefore, over 25- 100 years only very primitive soils were formed. The following features are inherent to them: (1) primitive soil profile (thickness 10-100 mm), (2) low levels of soil organic substance content (9.5-11.5 %), (3) alkaline indicators of the soil solution (pHH2O – 8.08-8.92, pHKCl – 7.42-8.23), (4) low levels of cation exchange capacity (6.34-8.47 mMol /100 g). By results of correlation calculations, among the factors of soil formation time (duration of soil formation) and input of plant ash elements’ fall are characterized by the maximum number of statistically significant correlation coefficients and their numerical values. In terms of chemical composition of the technosol, the values of organic matter content and exchangeable acidity (pHKCl) were the most predictable soil formation factors. Generally physical / chemical characteristics of geological rocks (as parent material) and time were the two most important factors in determining the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine).

Assessment of Concentrations of Heavy Metals in Soils around ESPRO Asphalt Production and Quarry Site, Wasinmi, Osun State Southwest Nigeria

This work examined the concentration of heavy metals in soil samples around ESPRO Asphalt Production and Quarry Site located in Wasinmi, Irewole Local Government Area, Osun State. A total of nine (9) soil samples were collected from three points with distances of 0, 1 and 2 km from the quarry site. Atomic Absorption Spectroscopy (AAS) was used to determine the concentrations of heavy metals in the soil samples. The results revealed that the mean values metal contents in the soil samples analyzed were in the order Fe>Zn>Cu>Cr>Mn>Pb>Cd. The concentration of the heavy metals in the soil samples were found to decrease as the soil depths increased from 0-25 cm and also as the spatial distances of the sampled locations increased from the quarry plant.
 The study also showed that low concentrations of Lead (Pb) had a mean concentration value of 0.87 ppm and Cadmium (Cd) with a mean concentration value of 0.29 ppm. It was also observed that Iron (Fe) had the highest mean concentration value of 148.8 ppm. The study concluded that quarrying activities raised the soil heavy metal contents up to the range of about 2 km away from the quarry site. This can be attributed to the number of years of mining and excavation activities in the study area and accumulation of the heavy metal concentrations over time and this could be dangerous to the site environments, especially for farming and groundwater exploration activities in the area.

Sequential Gaussian Simulation as a tool to improve PM10 sampling scheme in industrial sites

This paper is focused on the role of spatial and variographic analysis in the phase of sampling design. In particular, when dealing with environmental variables such as airborne dust concentration all over a selected domain, the best approach to catch the spatial structure of the variable itself, implies the full and more detailed coverage of the domain. In this study this goal is achieved by means of about fifty airborne dust concentration field surveys all over a square area 350 mt wide in a quarry plant in the center of Italy. These data, sampled according with a regular pattern, did not allow to catch the spatial structure of the variable itself thus avoiding a satisfactory variographic modelling. To improve the sampling scheme an infilling procedure was performed by adding an increased number of samples. The selection of these further samples, less than 10% of the total amount, was carried out using sequential Gaussian simulations in those zones of the domain in which the highest variability was recorded. The final outcome shown a good result determining a good upgrade in terms of variographic modelling and final estimation at the cost of few further samples.

Aspects on carbides transformations of Fe-based hardfacing deposits

Traditional arc welding was applied to create Fe-based hardfacing deposits onto carbon steel substrates used on the edges of excavation equipment in a quarry plant, in order to enhance their service lifetime. Three electrodes of different chemical composition were used to deposit 5–6 mm-thick protective overlayers. Prior to laboratory characterisation of the surface-hardened samples, the Thermocalc© software was used to predict microstructure features that could be possibly present in the weld metal areas after solidification, taking into account a 10% dissolution of the base metal in the molten pool. The calculation results were compared to the experimental findings from optical and scanning electron microscopy observations, X-ray diffraction and microhardness measurements. The thermodynamic calculations provided an accurate prediction of the phases obtained, whilst microhardness values and their distribution were found to be strongly depended on the nature of the carbides, their interaction with the liquid metallic matrix and their dispersion within the final solid.

Application of a Multi Stage Method to Assess the Landscape Alteration Induced by Quarrying Sites: A Comparative Analysis

The aim of this study is to provide a design tool to forecast the effects that extraction methods and reclamation plans will generate on the land surrounding quarry sites. The method is based on a graphical approach and it consists of three consecutive phases. The first phase focuses on the quarry plant and aims to quantify the extent of the quarry area exposed to a potential observer. Various possible exploitation methods are compared by plotting several layouts which are compatible with the characteristics of the mineral deposit. The extent of the resulting quarried area is then assessed for each layout. The second phase allows the selected solutions to be compared and analysed in relation to the topographic characteristics of the surroundings. Through the adoption of a parameter which quantifies the zone of visual influence of the quarry, the visual impact each exploitation method would have on the surrounding landscape throughout the lifetime of the quarry may be assessed quantitatively. The final phase combines the findings of the previous phases, thus taking into account both the extent of exposed quarried area and the features of the surrounding landscape so as to define input data in order to select and design the least intrusive layout. The procedure is tested on two case studies and, after comparing the two sets of results, some general principles are proposed and discussed which may be applied in relation to activities of both quarrying and reclamation.

Typology of Local Construction Materials from the Adamawa and North-West Regions of Cameroon

This article summarizes the different local construction materials observed in two regions of Cameroon (Adamawa and North-West). These raw materials were mapped and evaluated using various methods of investigation (spatial distribution, estimation of reserves, development of a database compatible with geo-referenced maps). The results obtained show three types of local construction materials (vegetal, pedological and geological) with quantitative estimation or distribution. Vegetal local materials include herbaceous savanna with strong dominance of straw in Adamawa region than the North West region. Pedological local construction materials include lateritic soils (ferruginous or clayey), harplan, sandy clay and sandy clay soil while geological local construction materials include volcanic, plutonic and metamorphic rocks. Many sites of these geological materials are suitable for the rock quarry plant. Adamawa region also contains sedimentary rocks constituted by metamorphic conglomerate and sandstones. Two main types of residential homes are constructed with these local construction materials in these regions of Cameroon. These include huts and houses.