Integrated Eco-sustainable System for Alluvial Gold Leaching-Recovery

An Integrated system for alluvial gold leaching-recovery was design to leach gold from alluvial ore as alternative to mercury and cyanide leaching. NaClO is obtained by NaCl 1 % in-situ electrolysis at pH 2 and used as leachate solution. Gold leaching optimization is achieved using a rotary drum reactor fed with the leaching solution, the process takes 6 hours and 95 % of gold recovery is obtained, the remnant gold from the alluvial ore is treated in an stationary reactor with NaClO 200 ppm at pH 2; reaching 99.6 % recovery of the total alluvial gold. This leaching-recovery alluvial system has the potential to replaced mercury and cyanide leaching process.

Biochar, Bentonite and Potassium Humate Effects on Saline Soil Properties and Nitrogen Loss

Aim: In order to study the effect of biochar, bentonite and potassium humate on saline soil characteristics, barley growth and nitrogen loss, a column experiment was conducted. Addition of the above mention materials was hypothesized to improve the characteristics of saline soil and decrease nitrogen loss in the leachate solution. Place and Duration of Study: Farm of Soils and Water Department, Faculty of Agriculture, Al-Azhar University, Cairo, Egypt during the winter season of 2019. Methodology: Biochar and bentonite were added with rates 0, 5 and 10 g.kg-1; and the rates of potassium humate were 0, 5 and 10 mg.kg-1. Excess irrigations were implemented three times (on 12th, 24th, 36th days) during growing season. Leachate solution was collected after each excess irrigation from each column to determine nitrogen loss. Results: Main results show that total organic carbon and soil porosity were increased by increasing the addition rates of the studied materials, especially at the high rates of biochar and bentonite. Also, the availability of water significantly increased. Addition of biochar and bentonite gave the highest decreasing in leachate solution volume. Nitrogen loss was decreased significantly at the highest rates of the studied materials, where the decrement percentage in leachate solution reached at 36.07%, 35.82 and 23.81 at the highest rates of biochar, bentonite and potassium humate, respectively. That led to increasing the retention of available nitrogen in saline soil. Fresh and dry weights of barley plants were increased significantly by increasing the addition rates of all amended materials. Macronutrients (NPK) content and uptake were increased significantly by increasing the addition rates of the studied materials. Conclusion: Research results proved that changes in soil properties caused a significant increase in barley growth and nutrients uptake. Addition of biochar and bentonite were the best option for improving saline soil properties, barley growth and nutrients uptake and reduce nitrogen loss by improving nitrogen retention and decreasing the leachate volume.

Leaching pattern of phosphate glass fertilizers with different compositions under Soxhlet distillation conditions

Glass fertilizers in the phosphate systems were melted at 900-950 °C with a soaking period of 1 h. Leaching study of these glasses with a maximum time period of 300 h was conducted under Soxhlet distillation condition with distilled water. Weight loss and the leach rates of the glass fertilizer samples were calculated from BET surface area measurements. They were in the range of 6.3x10-3 to 2.3x10-3 g.m-2.h-1 at 90 °C. The effect of different modifier ions like Na+, Fe3+, Mg2+, Ca2+, and K+ in the basic phosphate networks on melting and time of melting has been found to be evident. The pH determination ranging from 4.80 up to 7.50 of the leachate solution at ambient temperature under varying time intervals showed interesting and regular variations. The leaching study of such glasses under Soxhlet condition showed Ca2+, Mg2+, and K+ to be good candidates as modifier towards faster leaching. The findings have been corroborated in terms of ionic size, ionic radius, and hence the ionic potential of the modifier ions incorporated into the glass structure. The application of glass fertilizers was made on kharif paddy.

Preparation and Study of Corrosion Behavior of Some Simulated Radioactive Waste Glasses

To safe environment from radioactive waste it is important to fix them as radioactive waste glasses. The corrosion behavior of radioactive waste glasses in water is significantly important. Radionuclides return to the biosphere by means of leaching from waste form into ground water. Finally the ground water containing the radionuclide are transported to the surface. In this study, the preparation, characterization and leaching behavior of some borosilicate (BS) and lead iron phosphate (LIP) of different chemical composition doped with simulated nuclear waste oxide were investigated. We measured the pH found to be in the range from 6.78 up to 7.79 of the leachate solution at normal temperature and at varying time intervals. Leaching study of these glasses were conducted with the help of Soxhlet distillation apparatus with distilled water upto 24 hours and for BS9 - BS12 upto 100 hours duration. Weight losses were are measured with respect to time of leaching. Leach rate of some borosilicate glass samples loaded with uranium are calculated from surface area measurements. The results are reported in the range 1.34x10-4 g.m-2.hr-1 and 6.26 x 10-4 g.m-2.hr-1 respectively at 90°C.

Desulfurisasi Batubara Menggunakan Larutan Ekstrak Belimbing Wuluh (Everrhoa Bilimbi L)

Desulphurization process can improve the quality of coal and reduce the environmental pollution. In this study, the method used for desulphurization process was a leaching method using wuluh starfruit extract as a leaching agent. Starfruit extract obtained by grinded, filtered and extracted the starfruit solution. Coal was crushed by using a grinding ball mill, sifted to obtain samples of 80 mesh, 120 mesh, and 150 mesh. Coal was added with starfruit extract, heated on a hotplate stirrer at a temperature of 110oC, 300 rpm of stirring speed and 3, 4 , 5 hours of leaching time. Leachate solution were analyzed using XRF test. The results of the study showed that 80, 120 and 150 mesh could produce 1.777%, 1.556% and 1.053% of sulfur, respectively. Maximum decrease of sulfur occurred in 150 mesh with 5 hours of leaching time which could reach 0.261% of concentration. Ash content also could decreased from 11.43% to 6.18% and fixed carbon content from 42.15% rose to 51.33%. The desulphurization process using starfruit extract was influenced by the grain size of the coal and the contact time of leaching. The finer the grain size of the coal and the longer the leach contact time, the smaller the sulfur content obtained in the coal after the desulfurization process was carried out

Transport of Atrazine Via Leaching in Agricultural Soil with Mineral Oil Addition

ABSTRACT: Adjuvants, such as mineral oils, are widely used in the application of herbicides by reducing the drift and evaporation of the droplets and by increasing herbicide uptake by the plant. However, little is known about how mineral oil behaves when in contact with the soil. Thus, the objective of this research was to evaluate the transport of atrazine via leaching with the addition of mineral oil in a soil agricultural under laboratory conditions. To quantify the concentration of the herbicide along the profile of the very clay soil column (30 cm), 14C-atrazine (ring-U-14C) was used with 16,667 Bq of radioactivity per column in volume of 200 mL solution and 0 (control), 1, and 2% mineral oil (v/v) was added in the application volume. Atrazine was applied at the highest commercial dose recommended for sugarcane (4 kg ha-1). After simulation of a precipitation of 200 mm for 48 h, each column was sectioned into six parts of 5 cm and the analytes of each soil sample and the leachate were quantified by liquid scintillation spectrometry. The atrazine remained in the superficial layer of the soil, between 0 and 10 cm of depth, independent of the addition of mineral oil. No atrazine residues were detected in the leachate solution (> 30 cm) in any evaluated treatment. The addition of mineral oil at the time of application of pre-emergence atrazine did not interfere with the transport of this herbicide in the soil profile agricultural via leaching; therefore, the adjuvant may have positive effect only in the herbicide-plant relationship.

The Effect of Botanical Pesticide Extract Addition on the Nutrient Release of Fertilizer from Poultry Manure

Slow release fertilizer with pesticide (SRFP) has been formulated to provide nutrientenriched with pesticide using all natural compound. Matrix formulation is used with poultry manure(PM) as the nutrient source as well as the solid matrix for incorporating neem leave (Azadirachtaindica a.juss) and gendarussa leave (Justicia gendarussa burm) extract as the active compounds. Inthis study, the release of nutrient i.e. nitrogen by the addition of the two leave extracts during SRFPpreparation has been investigated using sand bed column leaching test. The leachate solution wasanalysed by Kjedahl method to measure total nitrogen amount released. Different volume of the leaveextract was investigated to study the effect of the extract addition on the release of the nitrogen. It isshown that the higher the volume of the leaves extract added during the granulation process, the fasterthe release of the nutrient.

КОНТРОЛЬ ЛІПОФІЛЬНИХ ТОКСИКАНТІВ У МОЛОЦІ З ВИКОРИСТАННЯМ МІКРОБІОЛОГІЧНОГО ЕКСПРЕС–МЕТОДУ

In recent years, Ukraine is constantly increasing livestock production. But at the same time, in many modern industries, veterinary and sanitary control of food is on insufficient or non–existent. In this connection the trading network can get dangerous foods for consumers.Today in the world there are numerous number of methods of analysis of food safety (spectrometry, photometry, chromatography, etc.). But in our country, a network of specialized laboratories which would be able to provide high–quality and objective analysis of the food is still very limited.It is also important to remember that the current chemical–analytical methods unfortunately unable to answer the general reaction of the organism to influence the recipient of the object, which is associated with several factors: the test object may contain toxicants with content during the study not predicted poorly understood substances, and importantly, is not considered character combined action of toxicants. That despite these shortcomings and remains an important method of determining the toxicity bioassay.The aim of our research was to establish the feasibility and effectiveness of the rapid microbiological method using ciliates Colpoda steinii to determine the toxicity of skimmed milk.Toxicity studies were carried out in parallel by three methods: bioassay in laboratory animals (white mice) and microbiological using as a test organism ciliates Tetrachimena piriformis and Colpoda steinii.The proposed method of using as a test organism ciliates Colpoda steinii, including the preparation of test culture ciliates Colpoda steinii, sampling investigational product, extracting samples of chemically pure acetone, filtering selected extract dilution leachate solution rod–Lozinski, introducing the filtrate into a test culture ciliates, temperature control resulting mixture at a temperature of +26 ... + 28 °C and determine the toxicity of the investigational product, observing the vital functions of ciliates during incubation.The research found that data on the toxicity of skimmed milk a certain prescribed manner identical data obtained using classical methods.Established that the strong toxicity of skimmed milk in the application of research results ciliates C. steinii get already at 3min. And weak toxicity or netoksychnosti – 1 hour.