the particle-size distribution psd of a powder, or granular material, or particles dispersed in fluid, is a list of values or a mathematical function that defines the relative amount, typically by mass, of particles present according to size. significant energy is usually required to disintegrate soil, etc. particles into the psd that is then called a grain size distribution.
a drywasher is a common desert mining tool for gold mining . a drywasher is like a highbanker, clarification needed since it uses a motor and a form of sluice, but it has no need for water. it drywasher operates by the use of air. by forcing air to flow up through the material as it moves down the sluice,.
geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. geotechnical engineering is important in civil engineering, but also has applications in military, mining, petroleum and other engineering disciplines that are concerned with construction occurring on the surface or within the .
as liquid enters the landfill cell, it moves down the filter, passes through the pipe network, and rests in the sump. as collection systems are planned, the number, location, and size of the sumps are vital to an efficient operation. when designing sumps, the amount of leachate and liquid expected is the foremost concern.
sonar sound navigation ranging is a technique that uses sound propagation usually underwater, as in submarine navigation to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. two types of technology share the name 'sonar': passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds .
slag is the collection of compounds that are removed. in many smelting processes, oxides are introduced to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractory lining from excessive wear. in this case, the slag is termed synthetic.
in 1902 the first electrolytic lead refining plant using the betts cell process began operation in trail. the consolidated mining and smelting company of canada ltd. was founded as a cpr subsidiary and began to develop the sullivan mine with its lead, zinc and silver ores, in kimberley in 1909.
metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means 'change in form'. the original rock is subjected to heat temperatures greater than 150 to 200 c and pressure 100 megapascals 1,000 bar or more , causing profound physical or chemical change.the protolith may be a sedimentary, igneous, or existing metamorphic rock.
slag is the glass-like by-product left over after a desired metal has been separated from its seven trust ore. slag is usually a mixture of metal oxides and silicon dioxide. however, slags can contain metal sulfides and elemental metals. while slags are generally used to remove waste in metal smelting, they can also serve other purposes, such as assisting in the temperature control of the smelting, and minimizing any re-oxidation of the final liquid metal product before the molten metal is removed from
the legal working age is the minimum age required by law for a person to work, in each country or jurisdiction.. some types of labor are commonly prohibited even for those above the working age, if they have not reached yet the age of majority.activities that are dangerous, harmful to the health or that may affect the morals of minors fall into this category.
a biofilter/bio-oxidation system is a fairly simple device to construct and operate and offers a cost-effective solution provided the pollutant is biodegradable within a moderate time frame increasing residence time = increased size and capital costs , at reasonable concentrations and lb/hr loading rates and that the airstream is at an organism-viable temperature.