Softened water, flow

A further increase in softened water flow drove the deaerator pressure down. This happened because the deaerator temperature also dropped. 

As the deaerator water level fell, the 120°F softened-water flow increased. 

But, dear reader, do not forget that when the steam inlet pressure-control valve is 100 percent open, any further increase of cool softened-water flow will suppress the deaerator s pressure. When the pressure of a vapor goes down, its volume goes up ... 

Dechlorinated and softened water flows to the RO skid through a 5.0-nm (nominal pore size) cartridge filter. The cartridge filter removes resin fines, particles and complexed colloids necessary to protect the RO membranes from particulate fouling. The RO membranes are thin-film composite (TFC) polyamide RO membranes (20 cm diameter X 100 cm long spiral wound elements) with rejection 99%. 

The individual membrane filtration processes are defined chiefly by pore size although there is some overlap. The smallest membrane pore size is used in reverse osmosis (0.0005—0.002 microns), followed by nanofiltration (0.001—0.01 microns), ultrafHtration (0.002—0.1 microns), and microfiltration (0.1—1.0 microns). Electro dialysis uses electric current to transport ionic species across a membrane. Micro- and ultrafHtration rely on pore size for material separation, reverse osmosis on pore size and diffusion, and electro dialysis on diffusion. Separation efficiency does not reach 100% for any of these membrane processes. For example, when used to desalinate—soften water for industrial processes, the concentrated salt stream (reject) from reverse osmosis can be 20% of the total flow. These concentrated, yet stiH dilute streams, may require additional treatment or special disposal methods. 

With storage tanks or processing equipment exposed to fire or radiant heat, the cooling of any metal above tire liquid level inside the vessel is critical. Metal surfaces that have a constant film of water flowing over them will not reach a surface temperature above the boiling point of water. This temperature is well below that which would subject the metal to loss of integrity because of softening. 

Determine TR—the lb/h of softened or demineralized treated water flowing to the deaerators... 

Suddenly, the flow of softened water would increase exponentially. The level-control valve would rapidly open. Yet, the level in the deaerator would slowly continue to fall, until the pump lost suction and cavitated. 

When the flow of softened water exceeded 80,000 lb/h, the heating steam pressure-control valve, shown in Fig. 15.1, would open to 100 percent. 

The escalating flow of colder softened water cooled down the deaerator. 

To solve this problem, Jim recommended to his boss that the softened water be preheated by using it on one side of a heat exchanger to cool off a waste foul liquor stream which was flowing to the effluent treatment pond. This heated the softened water from 120 to 160°F. The 50-psig steam demand was reduced by 25 percent. This reduced steam flow prevented the trays from flooding. 

Sodium Cation Exchanger (Zeolite) Process. This is the most widely used water-softening process in industrial, commercial, institutional and household applications. Hard water is softened by flowing it, usually downward, through a bed (2 feet to over 8 feet in thickness) of a granular... 

There are two solutions to soften water that is too hard. First, the water could be filtered to remove all of the calcium and magnesium ions. But this can be very expensive, so most people use a water softener instead. A water softener is a piece of equipment that can be attached to the water pipes that run into a house. This way, all the household water goes through the water softener before going into the other pipes in the house. Inside a water softener are small plastic beads. These beads have sodium ions (Na+) stuck on them. As the water flows over the bed of beads, the magnesium and calcium ions get replaced with the sodium ions. Since sodium is easily dissolved in water, it does not precipitate out in pipes like calcium and magnesium ions do. As a result, no scales form inside the pipes. Sodium ions do not react with soap to form soap scum, either, and they allow the soap to lather properly. 

Prior to wet-milling, the com must be softened by a steeping process developed specifically to produce optimum milling and separation of com components. Steeping is more than simple water soaking of com. It involves maintaining the correct balance of water flow, temperature, sulfur dioxide concentration and pH. Com is normally steeped for 24-40 hours at a temperature of 48°C to 52°C. By the end of the steeping period, the kernels should have (a) absorbed water to about 45% (wet basis) ... 

Softened water is supplied through a rotameter into the front connecting device between the partition plate and the mercury pump. It flows over the mercury level (washes the mercury) and enters the denuder through a pipe which is dipped under the level of the caustic solution. By this arrangement the escaping of hydrogen from the denuder is prevented. In the denuder water flows countercurrently to mercury and is withdrawn from the end of the denuder in form of a caustic solution. 

Softened water i containing sodium / salts flows to / faucets. f... 

Connect the cold-water supply line to the water intake connection of the saturator. Upstream of this connection, the water line should have a small water meter (1/2 in.) for use in calculating the feed rate, and there should be a shut-off valve between the meter and the saturator. To lower the amount of dirt to the saturator, a sediment filter (20 mesh) should be installed upstream of the saturator between the softener and water flow meter. 

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