Engineer's World

[...] a unit of area. ATM = 14.7 psia at sea level. As elevation rises above sea level, the atmospheric pressure is less. Absolute pressure (psia) Absolute pressure is the pressure measured from a zero [...]

[...] distillations plants use a vapor compression cycle where the water is boiled off at atmospheric pressure, the steam is compressed, and the condenser condenses the steam above the boiling [...]

[...]  your pump with the following formula: NPSHr = ATM + Pgs + Hv - Hvp Where: ATM = the atmospheric pressure at the elevation of the installation expressed in feet of head. Pgs = the suction [...]

[...] Regulation (NPDWR or primary standard) is a legally-enforceable standard that applies to public water systems. Primary standards protect drinking water quality by limiting the levels of specific [...]

[...] . Both are indicators of contamination with animal waste or human sewage. The largest public water systems (serving millions of people) must take at least 480 samples per month. Smaller [...]

[...] for new rules. A 1987 USEPA survey indicated there were approximately 202,000 public water systems in the United States. About 29 percent of these were community water systems, which [...]

[...] in water. Coliform bacteria naturally exist in the intestines of humans and certain animals. Thus, the presence of [...]

[...] , and organic matter that could tie up chlorine added for purification. 60-98% of coliform bacteria, 65-99% of viruses, and 60-90% of giardia will be removed from the water, along [...]

[...] or local authorities. Under the SDWA, EPA requires public water systems to monitor for coliform bacteria. Systems analyze first for total coliform, because this test is faster to produce [...]

[...] We may organize water treatment technologies into three general areas: Physical Methods, Chemical Methods, and Energy [...]

[...] When the objective of water treatment is to provide drinking water, then we need to select technologies that are not only the [...]

[...] large-scale systems, as the residual chlorine will prevent recontamination. Usually bulk water treatment plants first dilute to HTH to make a 1 % working solution at the rate of 14g HTH per [...]

Water must have eye appeal and taste appeal before we will drink it with much relish. Instinctively we draw back from the idea of drinking dirty, [...]

[...] used to accelerate liquids through pipes. How do pumps work? The fluid arrives at the pump suction nozzle as it flows through the suction piping. The fluid must be available to the pump with [...]

[...] inside the pump Suction pressure Suction pressure is the pressure at the pump’s suction nozzle as measured on a gauge. The suction pressure is probably the most important [...]

[...] It is the energy in the liquid required to overcome the friction losses from the suction nozzle to the eye of the impeller without causing vaporization. It is a characteristic of the [...]

[...] Drinking water standards are not the only regulations we need to comply with in the U.S. Today's Clean Water Act [...]

[...] and ultimately equipment selection depends on the standards set by the regulations. Drinking water standards are regulations that EPA sets to control the level of contaminants in the nation's drinking [...]

[...] scale in meeting drinking water demands in the United States. Compliance with drinking water standards is not uniform. Small systems are the most frequent violators of federal regulations.& [...]

[...] is only a positive force and it is either present or absent. Pressures inside the pump Suction pressure Suction pressure is the pressure at the pump’s suction nozzle as measured on a [...]

[...] the level of contaminants in the nation's drinking water. These standards are part of the Safe Drinking Water Act's "multiple barrier" approach to drinking water protection, which includes [...]

[...] the case of drinking water is established based upon legal criteria (e.g., the Safe Drinking Water Act, SDWA), and if non-potable or process plant water, may be operational criteria [...]

[...] CHLORINE Chlorine is familiar to most people as it is used to treat virtually all municipal water systems [...]