The trace elements, cobalt (Co) and manganese (Mn) were determined in the drinking water of Multan city and areas in its vicinity. For this purpose, ten water samples were collected from various points within a circle of one kilometer radius, each time around seven disposal units. Water samples were stored in sealed glass flasks at room temperature. The quality of these water samples was compared with reference samples collected from various far off places which were not affected by any disposal unit. Analysis for Co and Mn was carried out using Flame-Atomic Absorption Spectrophotometer. The highest concentration of Co (0.31 ppm) was found in New Multan disposal area, while highest concentration of Mn (0.45 ppm) was noted in Suraj Miani disposal area. The contents of Co and Mn metals in most of the points are found to be greater than permissible limits of WHO guide lines for drinking water.

This paper describes the results of a beneficiation study conducted on low-grade fluorite ore. The study was aimed at the development of a suitable beneficiation process to produce chemical grade fluorite concentrate. The representative sample of the ore was up-graded by leaching and flotation process. The important parameters of froth flotation process were optimized to obtain highest grade and recovery of fluorite concentrate. A single-factor variation method was applied to get the optimum conditions of the process. The rougher concentrate was reground to liberate fine locked fluorite particles and two cleaning flotation were employed in close circuit to achieve higher grade concentrate. A process flowsheet was designed in the light of these tests. After optimization of process parameters, the fluorite ore containing 62.24% CaF2 could be upgraded to a concentrate assaying 97.55% CaF2 with an overall recovery of 92.73%. The prepared fluorite concentrate meets the specifications of chemical grade and is suitable for production of fluoride based chemicals. Bangladesh J. Sci. Ind. Res. 58(2), 107-118, 2023

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A low-gradeantimony deposit originating from district Qilla Abdullah, Balochistan Province of Pakistan, containing stibnite as an economical mineral was beneficiated by froth flotation technique. Flotation parameters such as particle size of the feed, pulp density, pH of the pulp, agitation speed, type and dose of reagents (i.e. collector, frother, activator, regulator and modifier) and the conditioning time were studied on the basis of single-factor variation experiment in order to get the optimum grade and recovery. Regrinding of the rougher concentrate followed by cleaning andrecleaning of rougher concentrateensured a final concentrate grade of 65.12% Sb@ 85.79% recovery. This concentrate is suitable for the extraction of metal and production of chemicals. Materials and methodsA representative sample of the ore, consisted of lumps of various sizes, was obtained from Qilla Viala area of Qilla Abdullah district of Balochistan. It was jaw crushed to a size of 20-25 mm followed by roll crusher to product of 5-6 mm. A head sample for chemical analysis was obtained by coning-quartering and riffling of the crushed ore while the remaining ore was used for processing studies.The representative sample of ore was ground to pass 200 mesh sieve with the help of disc pulverizer (Denver, USA) and its chemical analysis was performed by gravimetric, volumetric and instrumental methods. Silica, alumina, lead, barium and sulphur were determined gravimetrically, while antimony by iodometric titration, iron by oxidation reduction titration, calcium and magnesium by complexometric titration. Sodium and potassium were estimated by flame photometer (PFP7, Jenway Limited, England). The chemical analysis of head sample and final concentrate is given in Table I & IV respectively. Flotation experiments were conducted in a flotation machine (Model: D-12, Denver, USA), using stainless steel cells of 1& 2 litres capacity. The ore was ground from 70-99% passing 200 mesh (74µm) to study the effect of particle size. Flotation feeds were prepared by wet grinding of roll crusher product in rod mill (Denver, USA) with solid to liquid ratio of 1:1. The effect of pulp density during conditioning was studied by varying the percentage of solids from 20-35%. Similarly the effect of pH was studied by varying it from 8.0 to 9.5 with soda ash. Impeller speed was varied from 900-1200 rpm to study the effect of agitation. Lead acetate was employed to activate stibnite mineral and its amount was varied from 500-1500g/t. Sodium silicate was added to depress the silicate gangue minerals and its quantity was increased from 200-1000 g/t. Sodium cyanide was applied to depress associated pyrite gangue in cleaning stage and its amount was varied between 100 and 500 g/t. Potassium amyl Table III. The flow-sheet developed from locked cycle tests for preparing high-grade antimony concentrate is given in Fig.10. Results and discussionIt is evident from the chemical analysis presented in Table-1 that 20.04% head grade of antimony is sufficient to exploit the...

A low-grade graphite ore originating from Kael area, Shounter Valley, Azad Kashmir, assaying 8.90% graphite content was upgraded by froth flotation technique to produce a commercial grade graphite concentrate. Mineral phases present in the ore were identified by using X-ray diffraction (XRD) technique. The variables of flotation process such as particle size of the feed, pH of the pulp, % solids of the pulp, speed of impeller, type and quantity of collecting and frothing agents, conditioning time and froth collecting time were optimized to get maximum grade and recovery of graphite mineral. The pH of the pulp was adjusted with sodium carbonate. Kerosene oil was used as collector while pine oil as frother respectively. Sodium silicate was employed as depressant. The grade of the final graphite concentrate produced was 85.80% C with overall recovery of 86.00%. Its surface morphology was studied using SEM-EDX technique while grain size by laser particle size analyzer.