Economic system carrying capacity

The chromium reduction process can be employed as batch treatment or continuous treatment. For small daily volumes of water or wastewater that are less than 150,000 L (40,000 gal), the most economical system is batch treatment in which two tanks are provided, each with a capacity of one day s flow. Reduction, precipitation, and sedimentation are carried out in one tank, while the other is used to collect the waste. In a typical batch system, the required dosage of acid and sodium metabisulfite is added to the tank and the contents are mixed for 15 min to ensure complete reduction of the chromium. 

Simply outbred the carrying capacities of our planet s social, economic and ecological Systems. 

For materials of moderate to low porosity, a good starting vacuum level is 0.6 to 0.7 bar (18 to 21 in Hg), as the capacity of most vacuum pumps starts to fall off rapidly at vacuum levels higher than 0.67 bar (20 in Hg). Unless there is a critical moisture content which requires the use of higher vacuums, or unless the deposited cake is so impervious that the air rate is extremely low, process economics will favor operation at vacuums below this level. When test work is carried out at an elevation above sea level different than that of the plant, the elevation at the plant should be taken into account when determining the vacuum system capacity for high vacuum levels (>0.5 bar). 

Back in Chapter 5 we discussed a method for quantitatively incorporating the economics of control into conventional steady-state design economics. For a given process and control system, the idea is to specify upper and lower limits on product quality and determine what fraction of the time the process is within these specification limits. The capacity of the plant is equal to this fraction times the product flow rate. Periods of off-specification production must be handled by reworking or disposing of the material, which carries some economic cost. The steady-state economic calculations are made using the on-specification capacity. 

An agreement of collaboration between Plastr and Tomas Bata University in Zlin (TBU) has been concluded. TBU carries on study programs and builds research capacities among others in the field of polymers, material engineering, environment protection, applied informatics, applied economics, design, advertisement - all could be subjects of collaboration. Plash will be active in influencing education system. 

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