Water recirculation

Pharmaceutical Industry. In the pharmaceutical industry, sterility of deionized water systems is maintained by using an ozone residual. The ozone residual concentration is maintained at >0.3 ppm ppm in the water recirculation loop. Prior to product compounding, the ozone residual is removed by contact with uvirradiaton for <1 s. Ozone also is used to oxidize pyrogens from distilled water destined for intravenous solutions. 

An ammonia-water recirculating solution of 62 wt % is to be stripped of the ammonia for recovery by condensa-... 

Drop the water level if necessary to allow for the acid and ensure that all hose lines are tied down. Begin full water recirculation. 

The system has limited usage and no hot water recirculating pump - in effect it presents an ideal environment for the growth of Legionella and the worst features of system design ... 

Water inlet and outlet. These are often connected to temperature-controlled water recirculating baths. The prisms and your samples in the prisms can all be kept at the temperature of the water. 

Once-through cooling water. Recirculating cooling system blowdown. Ash transport water ... 

Figure 2 shows the outline of fluidized bed process. Seeds are fluidized by the upflow of influent and recirculated water. Recirculation is necessary to maintain water quality of the influent average, lower phosphate concentration in the influent, and also to obtain flow rate for fluidization. 

The integration of the turbine pressure regulator and control system with the reactor water recirculation flow control system permits automated... 

Nuclear Boiler Assembly. This assembly consists of the equipment and instrumentation necessary to produce, contain, and control the steam required by the turbine-generator. The principal components of the nuclear boiler are (1) reactor vessel and internals—reactor pressure vessel, jet pumps for reactor water circulation, steam separators and dryers, and core support structure (2) reactor water recirculation system—pumps, valves, and piping used in providing and controlling core flow (3) main steam lines—main steam safety and relief valves, piping, and pipe supports from reactor pressure vessel up to and including the isolation valves outside of the primary containment barrier (4) control rod drive system—control rods, control rod drive mechanisms and hydraulic system for insertion and withdrawal of the control rods and (5) nuclear fuel and in-core instrumentation,... 

It may well be found that evaporation is much less than anticipated due to, for example, inadequate airflow through the tower, insufficient rate of water recirculation, poor distribution of hot water spray through the tower, a fouled or damaged tower fill, a low hot water temperature returning to the tower, or a very high relative humidity. Such a reduced evaporation may be evidenced by only a small difference in the hot water temperature to the tower and the cold water temperature from the tower (AT). 

In the context of discussing cooling water recirculating pH, consider the relative rates of decrease in HOC1 and HOBr availability with increase in pH, as shown in Table 6.1 (HOI also included for comparison). 

The daily and annual water consumption is related to a number of factors, including the hours and days of operation per year, cooling water recirculation rate, current atmospheric conditions, seasonal weather, operational differences, actual cooling tower incoming and outgoing... 

Almost never take a person s word for the water recirculation rate. Check the number of pumps available and the number operational, read the pump plate, use pump curves, read the pump manual, measure using pitot tubes (measures the total pressure and hence indirectly the velocity), orifice plates, V-notch weirs, and distribution deck levels, or calculate based on amperage draw and the discharge pressure, to confirm the volume of water actually circulating in the system. 

Continuous water recirculation system, whereby cooling water picks up heat by being pumped through a process heat source or heat exchanger and then over a cooling tower, open to the air, whereupon the sensible heat gained is lost by an evaporation process. 

A large source of water for reuse may be obtained by reclaiming polluted water. Sources of polluted water emanate from domestic wastewater, industrial waste solutions, agricultural effluent as runoff water, recirculated greenhouse water, and fish pond waste. All these must be treated to a tolerable quality to prevent deterioration of the soil and aquifers, and pollution of lakes, rivers, and the sea. Above all, this is a source of usable water. 

Water samples taken from various locations (denoted in the National Printing Bureau Domestic Water Systems Preliminary Investigation Report),1 indicated the high iron content in samples taken from locations where the cold and hot water are mixed, e.g., the heat exchange loop and hot water recirculation pump (Figure 7.22). 

Fortunately we can readily solve many of the problems associated with a direct supply of cooling water. For example, in Fig. 4.15 we have provided a water recirculation loop to maintain a large constant flow of water through the jacket. Fresh cooling water is added to the loop to maintain the desired reactor temperature. This arrangement keeps... 

A way to reduce motive steam consumption in a steam-ejector system with barometric condensers is to lower the temperature of the water recirculating in the... 

To recover the liquid product from the reactor product gas stream. Biocarbons Corporation uses a venturi scrubber with a closed water recirculating loop that (for commercial operation) is kept above the water dew point of the gas to avoid net water production (An electrostatic precipitator would be used downstream of the scrubber... 

Zellars-Williams, Inc., "Water Recirculation System Balance of Central Florida Phosphate Mining. Mine I Calculations. 1974-1975 Rainfall Calculations." BuMines Open File Report No. 120-77. Tuscaloosa. AL. 1977. p, IV. 

Zellars-Williams, "Water Recirculation System Balance of Central Florida Phos 4iate Mining, BuMines OFR 120-77, NTIS PB 270 359. U.S. Bureau of Mines. Tuscaloosa, AL. Jan. 1977, 83 pp. 

Membrane-based separation processes are also used in large-scale applications with closed water recirculation. Examples for such processes are electrophoretic coatings in the automotive industry, or the work-up of detergent solutions and caustic solutions from the beverage industry or water from dye baths. The use of membranes in such processes reduces on the one hand the demand on fresh-water. 

Quenching of the gaseous products leaving the reaction zone in a tower provided with precooled water recirculation, to which ammonia Is added for the absorption of chloral. The liquid fraction withdrawn is essentially recirculated and partly settled to recover the ethylene dichloride w hich is also entrained. 

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