Pumps steam condensate

Condensa.te Recovery Pumps. The condensate recovery pump is a unique design that utilizes a motive steam or an air supply to move condensate. It can be appHed to capacities up to 23,000 kg/h (50,000 lb /h), providing valuable recovery of condensate or other Hquids, which otherwise would be wasted. 

The prevacuum technique, as its name implies, eliminates air by creating a vacuum. This procedure faciUtates steam penetration and permits more rapid steam penetration. Consequendy this results in shorter cycle times. Prevacuum cycles employ either a vacuum pump/steam (or air) ejector combination to reduce air residuals in the chamber or rely on the pulse-vacuum technique of alternating steam injection and evacuation until the air residuals have been removed. Pulse-vacuum techniques are generally more economical vacuum pumps or vacuum-pump—condenser combinations may be employed. The vacuum pumps used in these systems are water-seal or water-ring types, because of the problems created by mixing oil and steam. Prevacuum cycles are used for fabric loads and wrapped or unwrapped instmments (see Vacuum technology). 

Condensate Polishing. Ion exchange can be used to purify or poHsh returned condensate, removing corrosion products that could cause harmful deposits in boilers. Typically, the contaminants in the condensate system are particulate iron and copper. Low levels of other contaminants may enter the system through condenser and pump seal leaks or carryover of boiler water into the steam. Condensate poHshers filter out the particulates and remove soluble contaminants by ion exchange. 

Our example system has a flow-controlled feed, and the reboiler heat is controlled by cascade from a stripping section tray temperature. Steam is the heating medium, with the condensate pumped to condensate recovery. Bottom product is pumped to storage on column level control overhead pressure is controlled by varying level in the overhead condenser the balancing line assures sufficient receiver pressure at all times overhead product is pumped to storage on receiver level control and reflux is on flow control. 

C 0.35 Recovery of low level waste heat f space heating, district heating syste Absorption cooling. Recovery of steam condensate and flash steam. Heat pump for evaporation, drying, etc. 3r m. 

Vacuum Distillation - Heavier fractions from the atmospheric distillation unit that cannot be distilled without cracking under its pressure and temperature conditions are vacuum distilled. Vacuum distillation is simply the distillation of petroleum fractions at a very low pressure (0.2 to 0.7 psia) to increase volatilization and separation. In most systems, the vacuum inside the fractionator is maintained with steam ejectors and vacuum pumps, barometric condensers, or surface condensers. 

This cooling water is usually arranged in a closed loop with the water being pumped through secondary coolers or over cooling towers and then returned to the jackets for reuse. Water quality must be good, with steam condensate being preferred, properly treated to prevent corrosion, etc. 

Condensate system requirements are to check the condensate pumps, steam traps, and overall condensate return system. A loss of condensate return necessitates an increase in MU water to compensate for the shortfall in the FW system. 

All the water from the steam condensate lines and the water baths (D-501) will be pumped into the hot-water storage tanks, unless they are full. In that case, a control valve will divert the water from the water baths into the wash-water tanks. An overflow pipe will send any excess water from these tanks to the waste treatment facilities. 

Steam condensate at 1 atm and 95°C (Pv = 526 mmHg) is returned to a boiler from the condenser by a centrifugal boiler feed pump. The flow rate is 100 gpm through a 2.5 in. sch 40 pipe. If the equivalent length of the pipe between the condenser and the pump is 50 ft, and the pump has an NPSH of 6 ft, what is the maximum height above the condenser that the pump can be located ... 

Water vapor is frequently removed by pumps that operate with water or steam as a pump fluid, for example, water ring pumps or steam ejector pumps. This depends considerably on circumstances, however, because the economy of steam ejector pumps at tow pressures is generally far inferior to that of rotary pumps. For pumping a vapor - gas mixture in which the vapor portion is large but the air portion is small, the vapor can be pumped by condensers and the permanent gases, by relatively small gas ballast pumps (see Section 2.1.5). 

The stripped 230°F BFW drains into the large deaerator drum. This drum simply provides residence time for the high-pressure BFW pumps, which supply water directly to the boilers. Recovered steam condensate, which should be air-free, is fed to this drum through a separate nozzle. 

The vapor is drawn into a steam jet (discussed in Chap. 16). The steam condensate flows into the boot or hot well. The water in the boot is slightly subcooled. This is accomplished by a pair of baffles that create a small zone of condensate backup. The subcooled condensate, cooled to perhaps 10°F below its boiling or bubbling point, is easier to pump. As the pressure in the hot well is subatmospheric, the hot-well pump typically develops a AP of at least 30 to 50 psi. 

Finally, the steam turbine s buckets can foul with hardness deposits from the steam. This reduces the turbine efficiency, and may prevent a pump from running at its rated speed. Injecting steam condensate into the steam supply can remove such deposits. 

In the other design, PWRs have two closed loops of water circulating in the plant plus a third, external loop to remove the waste heat. Water is pumped through the reactor core in the primary coolant loop to moderate the neutrons and to remove the heat from the core as in the BWR. However, the reactor vessel is pressurized so that the water does not boil. Steam is necessary to run the turbines, so the primary loop transfers the heat to a secondary loop. The water in the secondary loop is allowed to boil, producing steam that is isolated from both the core and the outside. The water in the primary loop usually contains boron (as boric acid H3BO3 0.025 M) to control the reactivity of the reactor. The steam in the secondary loop is allowed to expand and cool through a set of turbines as in the BWR the cold steam condenses and is returned to the primary heat exchanger. A third loop of water is used to maintain the low-temperature end of the expansion near room temperature and remove the waste heat. 

The next table, Table 8.30, is similar to the previous, but without any condenser. A steam condensate accumulator with condensate pumps is required however, many installations simply return the exhaust steam in an existing LP header directly, without any supplemental equipment other than piping added to the noncondensing turbine driver. Piping is... 

Several local newspaper articles explained that during these startups, steam is provided to displace any air in the system prior to the introduction of any oil. At the beginning of the startup, temperatures in the unit are cool enough to condense some of the steam into water. Water (steam condensate) collects in the E-l Fractinator and then is pumped into another part of the unit, the F-7 Drum. Under normal startup procedures the operating crew drain all of the water from the F-7 Drum before the hot oil is admitted. 

The system s Second Law efficiency rises as the work/heat ratio increases (Figure 7). This is partially due to improved performance of the turbine, pump, and condenser and the higher temperature steam from the boiler. This considerably decreases the available-energy destruction due to heat transfer in the boiler. Thus, the turbine can take advantage of this for the production of shaft work. 

Electrolyte container. 2 — Cells, J — Catholyte container, 4 — Anolyte (persulphnrlo acid) container, 5 — Lead distillation coil, 6 — Heating steam inlet, 7 — Tank tor steam condensate, S — Separator of liquid from vapour, 9 — Auxiliary distillation equipment, 10 — Main column for fractional condensation, 11 — Second column, 12 — Barometric oondenser, 13 — Vacuum pump, 14 — Acid dilution vessel. 13 — Acid purifier. 

The pump used to transport the steam condensate in the power cycle from the condenser to the boiler has an efficiency of 80% (i.e., 80% of the work done by the pump is on the condensate). What size pump (kW and horsepower) is required for the estimated water flow rate What assumptions have you made in these calculations ... 

S l 12 Design a heat exchanger to pasteurize mill by steam in a dairy plant. Milk is lo flow through a bank of 1.2-cni internal diameter lubes while. steam condenses outside the tubes at I aim. Milk is to enter the tubes at 4 C, and it is to be heated to 72°C at a rate of 15 L/s, Making reasonable assumptions, you are lo specify the tube length and the number of tubes, and the pump for the heat exchanger. 

This train of thought is the foundation for a new process outlined in Figure 34 [41]. It is termed enforced ebullition process as in addition to steam as primary heating agent, a hot gas is used to bring the liquor from the steam condensation temperature to boiling. The process can be described as follows By means of pump 1, the sulfite liquor is fed through an in-line mixer 2, where it is heated to 240 C by steam injection. This raises the... 

---