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The operation and exploitation of the Pilares breccia-pipe copper ore deposit and its subsequent cessation of activities in 1945 generated approximately 20 million tons in mine tailings and waste, currently covering a 19 hectares surface located within the urbanized area of Nacozari de Garcia, Sonora. The studied mine tailings are unconfined, with unstable slopes of 50°, lack of vegetation and seasonal efflorescent salts haved formed on the surface. Such characteristics generate high eolian and water erosion and the possible collapse of material. In this work, calculated erosion is classified as severe to very severe. Granulometric characteristics of the tailings mark significant differences in the intensity of water erosion. The physical characterization of the tailings shows two areas of different granulometry that influence in the oxidation of sulfides and metal release: an area of large particle size, and another of fine particle size produced by the flotation process. Climate indexes were estimated for a time period from 1960 to 2011. The aridity index of Martonne shows a rank from 47 to 66, varying from humid in the '60s and '70s to perhumid in the '80s, and humid at present. The Lang index shows values from 15.2 to 22.8, which classifies as a steppe. Copper contents in residential soils and airborne dust collected at two meters height exceed the geochemical background. [ABSTRACT FROM AUTHOR]

The development of a software package for evaluating the environmental pollution due to gaseous effluents and powders from pirometallurgical processes furnaces is presented. The system consists of hoods to draw gaseous effluents and powders, decantation equipments for coarse particles, gas cooling and powder cleaning, aspiration and unloading ducts, fan and stack. The temperatures are estimated throughout the system, the heights speed and the load losses are corrected. The software performs the energy balances of the process, calculates the area of the cooler, the load losses and the centrifugal fan power. It also allows checking the calculations, simulates extreme situations and obtaining results that save calculation time for a successful decision making both for the proper function of the system and to establish the correct actions for reducing pollution produced by pirometallurgical processes. [ABSTRACT FROM AUTHOR]

The formulation of cow milk-soymilk powder was defined using the technology of physical blended of powders. In the formulation of the product, soymilk powder, powdered whole milk, sugar, fine salt, milky flavor and a premix of salts of the minerals and vitamins was employed. Three experimental runs were carried out to determinate the formulation. In each run 100 kg of the product were used to define by means sensory evaluation the formulation using a scale of points for attributes. The physical-chemical and microbiological properties of the powdered product were determined. The obtained food product presented good microbiological and nutritional quality and sensory acceptance. [ABSTRACT FROM AUTHOR]

The formulation of the powdered modified lactosan using spray-drying technology was defined. The product formulation included milk solids, vegetable fat lacto-350, lactose, Vitamin-A and Vitamin-D. Three experimental runs were carried out. In each run 500 kg of the product were employed to define by means sensory evaluation tests the formulation using a scale of points for attributes. The physical-chemical and microbiological properties of the powdered and diluted product were determined. The obtained food product presented good microbiological and nutritional quality and sensory acceptance. [ABSTRACT FROM AUTHOR]

The formulation of soymilk was defined with added vegetable fat using a spray-drying technology. The product formulation included solids of soybean, vegetable fat lacto-350, sugar and fine salt. Three experimental runs were carried out to determinate the formulation. In each run 500 kg of the product were employed to define the formulation by sensory evaluation tests using a scale of points for attributes. The physical-chemical and microbiological properties of the powdered product were determined. The obtained product was used as substitute of powdered milk in milk for consumption and in powdered mixtures for ice creams. The obtained food product presented good microbiological and nutritional quality and sensory acceptance. [ABSTRACT FROM AUTHOR]