Application of Some Natural Porous Raw Materials for Removal of Lead and Zinc from Aqueous Solutions

This chapter discusses the adsorption of lead and zinc ions onto a natural zeolite (clinoptilolite) and zeolite bearing tuff (stilbite) from aqueous solution, whereby the main parameters were the effects of initial pH of solution, mass of adsorbent, and initial metal concentration in solution

Computer treatment of gravity concentration from chromite ore

The application of the computer program enables a quick quantitative calculation of the gravity concentration involving all available and acceptable equations which define the accomplishment of the technological operation

Corporate against corporate management

In contemporary economic performance, corporate governance is considered an essential prerequisite in building a successful system for creating an attractive investment climate, which is characterized by competing companies oriented and efficient financial markets. Good corporate governance is based on principles of transparency, bias, efficiency, timeliness, completeness and accuracy of information at all levels of management. Companies with good corporate governance and afford easier access to capital markets. The private sector and the movement of financial capital, affect the implementation of corporate governance and influence the development of a culture of corporate governance. Very important to distinguish between corporate governance and corporate management

КОНТРОЛА НА ФИЛТРАЦИОНИТЕ ПРОЦЕСИ НИЗ ТЕЛОТО НА БРАНАТА НА ЈАЛОВИШТЕ 3-2 НА РУДНИК САСА

Процесите на филтрирација низ телото на песочната брана кај конвенционалните хидројаловишта, кои се градат со низводен метод, се еден од најважните елементи кои директно влијаат на стабилноста на браната, а со тоа и на целокупната инсталација на хидројаловиштата. Со контролирање на нивото на провирните линии низ телото на браната, ние индиректно ја контролираме работата на дизајнираните дренажни ќилими, чија функција е да ја фатат филтрационата вода низ телото на песочната брана и да се исцедат низводно во форма на дренажна вода. Овој труд го покажува начинот на контрола на процесите на филтрација низ телото на песочната брана бр. 3-2 кај рудникот Саса преку систем на пиезометри и преку редовно испитување на основните геомеханички параметри на песокот од кој е изградена браната

Effect of Competing Cations (Cu, Zn, Mn, Pb) Adsorbed by Zeolite Bearing Tuff from Macedonia

Zeolite bearing tuff (stilbite 27%) from Vetunica deposit, Republic of Macedonia was investigated as an adsorbent for removal of copper, zinc, manganese and lead ions from synthetic aqueous solutions. The aim of this study was to investigate the influence of the presence of competing cations on the individual adsorption of Cu2+, Pb2+, Zn2+ and Mn2+ from a solution containing a mixture of all these metal ions, by zeolite bearing tuff. The obtained results show that the adsorption of studied ions in single and multi-component solution onto zeolite bearing tuff occurs efficiently. The amount adsorbed from multicomponent solutions was affected significantly, except for Pb2+ where the difference between single and multi-component solution is minimal, almost insignificant. The selectivity of zeolite bearing tuff was also determined for the respective heavy metal ions. The selectivity series obtained for single and multi-component solution was: Pb2+ > Cu2+ > Zn2+ > Mn2+

Removal of lead ions from acid aqueous solutions using zeolite bearing tuff

Water pollution come from a number of different sources, and pollutants are divided up into various classes, such as organic pollutants, inorganic fertilizers, metals and radioactive isotopes. Organic pollutants are susceptible to biological degradation, unlike heavy metals which are not degrade into harmless products. Heavy metals are a common pollutant found in various industrial effluents. They are often encountered in mining operations and acid mine drainage. Because heavy metals are highly toxic and are non-biodegradable, therefore they must be removed from the polluted streams in order to meet increasingly stringent environmental quality standards. For this reason, in this paper it is presented research of removal of lead ions from acid aqueous solution using zeolite bearing tuff. The physical and chemical properties of the used natural material (zeolite bearing tuff) are characterized by x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and AES - ICP. In order to determine the effectivity of zeolite bearing tuff a series of experiments were performed under batch conditions from single ion solutions. Experiments were carried out at different initial ions concentration, different initial pH values and different adsorbent mass. The adsorption kinetics is reasonably fast. It means that in the first 20 min approximately 90% of Pb2+ is adsorbed from single ion solutions

Application of dispersion analysis for determining classifying separation size

The paper presents the procedure of mathematical modelling the cut point of copper ore classifying by laboratory hydrocyclone. The application of dispersion analysis and planning with Latin square makes possible significant reduction the number of tests. Tests were carried out by D-100 mm hydrocyclone. Variable parameters are as follows: content of solid in pulp, underflow diameter, overflow diameter and inlet pressure. The cut point is determined by partition curve. The obtained mathematical model and the values of the coefficients make it possible to find the classifying cut point for variable factors

Removal of Heavy Metals from Aqueous Solution using Clinoptilolite and Stilbite

Heavy metals are highly toxic and they must be removed from the polluted streams. Аdsorption by zeolites is currently considered to be very suitable for wastewater treatment because of its simplicity and cost effectiveness. The aim of this investigation was to compare adsorption efficiency of heavy metals (Cu, Zn, Mn and Pb) from aqueous solution using two different types of natural zeolite: clinoptilolite from Bulgaria and stilbite from Macedonia. The obtained information will be basis for further research for acid mine drainage treatment with zeolite. The adsorption of Cu, Zn, Mn and Pb from aqueous solution using clinoptilolite and stilbite is effective. Copper and zinc ions are better adsorbed using stilbite, manganese ion is better adsorbed using clinoptilolite as adsorbent and for lead ion a both of used adsorbent gave a similar results. According to the maximum adsorption capacity (qe) was determine the selectivity of clinoptilolite and stilbite, for the respective heavy metal ions. The selectivity series obtained about clinoptilolite was: Pb2+ > Cu2+ > Zn2+ > Mn2+, and about stilbite was Pb2+ > Cu2+ > Zn2+ > Mn2+. From the kinetic modelling, the pseudo-second order kinetic model gave a better fits than pseudo-first order kinetic model for adsorption of Cu, Zn, Mn and Pb onto clinoptilolite and stilbite

Vehicle routing and scheduling – The traveling salesman problem

The classification of routing and scheduling problems depends on certain characteristics of the service delivery system, such as size of the delivery fleet, where the fleet is housed, capacities of the vehicles, and routing and scheduling objectives. In the simplest case, we begin with a set of nodes to be visited by a single vehicle. The nodes may be visited in any order, there are no precedence relationships, the travel costs between two nodes are the same regardless of the direction traveled, and there are no delivery-time restrictions. In addition, vehicle capacity is not considered. The output for the single-vehicle problem is a route or a tour where each node is visited only once and the route begins and ends at the depot node. The tour is formed with the goal of minimizing the total tour cost. This simplest case is referred to as a traveling salesman problem (TSP). An extension of the traveling salesman problem, referred to as the multiple traveling salesman problems (MTSP), occurs when a fleet of vehicles must be routed from a single depot. The goal is to generate a set of routes, one for each vehicle in the fleet. The characteristics of this problem are that a node may be assigned to only one vehicle, but a vehicle will have more than one node assigned to it. There are no restrictions on the size of the load or number of passengers a vehicle may carry. The solution to this problem will give the order in which each vehicle is to visit its assigned nodes. As in the single-vehicle case, the objective is to develop the set of minimum-cost routes, where “cost” may be represented by a dollar amount, distance, or travel time. If we now restrict the capacity of the multiple vehicles and couple with it the possibility of having varying demands at each node, the problem is classified as a vehicle routing problem (VRP). In this paper will be presenteds the TSP procedure for delivery and routing of new product L-carnitine from Koding – Skopje which life development is in the introduction or development phase

Идејно решение за изградба на јаловиште бр. 2 Тораница – технолошки аспекти

Целта на овој труд е да се анализираат и разработат технолошките аспекти кои се битни при изработката на идејно решение за формирање на ново јаловиште во рударската индустрија. Како конкретен пример ќе биде анализирана потребата за изградба на ново јаловиште на рудникот Тораница – Крива Паланка. Во трудот ќе биде направен осврт на концепциското решение за формирање на јаловиштето, проценка на технолошките податоци, прелиминарна пресметка на волуменот и векот на експлоатација, концепциско решение за хидротранспортот на флотациската јаловина, одлагањето на јаловината, диспозицијата на објектите и др