Specifications: Spray-Type Deaerator [Source:

Kansas City Deaerator Company]

1. The deaerator shall be a horizontal, direct contact, spray-type unit with integral storage, and shall be designed for two-stage operation such that deaera-tion is guaranteed over the full load range without recirculadeaera-tion pumps. The deaer-ator shall have a stainless steel liner in the spary area to reduce oxygen pitting of the unit in the area of concentrated oxygen.

2. Design conditions are as follows:

a. Total outlet capacity (lb/hr) b. Makeup water (lb/hr, min)

Makeup water (lb/hr, max)

Makeup water temperature (°F, min) Makeup water temperature (°F, max) c. Condensate return (lb/hr, min)

Condensate return (lb/hr, max) Condensate return temp (°F, min) Condensate return temp (°F, max) d. High-temperature flashing drains

lb/hr min lb/hr max

Temperature (°F, min) Temperature (°F, max)

e. Deaerator design pressure (psig) 30

f. Deaerator operating pressure (psig.) 2–5 psig Steam will be supplied by user so as to maintain a

satu-ration temperature corresponding to positive design operating pressure.

g. Storage volume, gallons:

as measured below overflow level. Overflow level not to exceed 75% of the tank diameter.

h. Minutes of operation w/storage, approx. 10.0 (15.0 min optional) at rated capacity.

3. The first stage shall consist of a 304 stainless steel water box assembly containing spring-loaded, variable orifice spray valves mounted to spray into the vent condensing chamber and containing a stainless steel vent pipe positioned to permit efficient venting to the atmosphere. Spray valves shall be cast from type 316 stainless steel and shall produce a hollow cone, thin-filmed spray pattern over the range of 5–200% of rated valve capacity to assure rapid heating and stable venting. Valves shall operate with the use of Teflon guides to assure quiet operation. A heavy-gauge collection basin shall be provided to accumulate pre-heated water for entry into the scrubber.

4. The second stage shall consist of a deaerating steam scrubber, receiving preheated water from a collection basin downcomer, and receiving pure steam from a variable area steam distributor, such that a vigorous scrubbing action occurs to strip the water of its final traces of oxygen and carbon dioxide. Scrubber outlet shall be positioned to permit exiting steam to flow into the vent condensing chamber for stage 1 heating, deaerating, and venting.

5. The deaerator shall be constructed in accord with the ASME Code, Section VIII, Division 1, for unfired pressure vessels and designed for 30-psig–

design pressure (50 psig optional; full vacuum optional). All steel plate shall be ASTM grade SA-516-70. A corrosion allowance of at least 1/16 in. (1/8 in.

optional) shall be included over the ASME calculated thicknesses.

6. Access to deaerator internals and storage shall be provided through a 12″ ⫻ 16″ manhole.

7. The deaerator shall include heavy-duty saddles that provide continuous support over a contact arc of not less than 120 degrees of storage vessel circumfer-ence.

8. All connections necessary to accommodate piping and specified acces-sories shall be included such as to comprise a complete, working unit, NPT cou-plings shall be provided for connections 2 1/2 in. and smaller. Connections above 3 in. connections will be pad flange, flanged pipe, or NPT coupling. All intercon-necting piping and bridles will be furnished by purchaser. The deaerator shall be

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shipped as complete as possible. Final piping assembly shall be furnished by the contractor.

9. The vent condensing system shall provide for the efficient release of oxygen and carbon dioxide with minimum loss of steam, and shall be complete with stainless steel vent pipe.

10. The deaerator shall be guaranteed

a. To deliver specified capacity at the saturated steam temperature corresponding to the steam pressure within the heater.

b. To deliver specified capacity with an oxygen content not to ex-ceed 0.005 cc/L as determined by the Winkler test, or equal, and with a free carbon dioxide content of zero as determined by the APHA test, one time through without recirculating pumps.

c. To be free from defects in material and workmanship for a period of 1 year from date of initial operating or 18 months from date of shipment, whichever occurs first.

11. Optional: The deaerator shall be in accordance with the Heat Ex-change Institute 1992, 5th Ed. and shall include the following to assure a safe, reliable vessel.

• 1/8 in. corrosion allowance

• Full penetration welds

• Post weld heat treatment

• Wet fluorescent magnetic particle inspection

• Stainless steel inlet and water box

• Allowable nozzle velocity

12. Optional: The following accessories shall be provided;

One (1) high-capacity pressure relief valve (full relief by others). Set at vessel design pressure.

One (1) vacuum breaker valve.

One (1) water inlet regulating valve to pass lb/ hr at inlet pressure from psi to psi (optional by-pass).

One (1) internal level controller w/pneumatic actuator. (Optional: two [2]

mechanical float switches for low [and high] water level. SPDT Nema 4 rated.)

One (1) mechanical overflow tray pr valve with float control.

One (1) steam pressure reducing valve (PRV). To reduce available steam pressure from—psig to deaerator operating pressure (Optional by-pass).

One (1) dial pressure gauge complete with a siphon and cock.

One (1) stainless steel trim vent valve.

One (1) separable socket thermometer.

13. OPTIONAL: When a Package unit is requested, the following addi-tional components shall be included. The package assemble shall be factory pre-assembled and shall be broken down for shipment due to clearances.

a. Structural stand build per OSHA. Stand is prefit up to match up with deaerator. The stand will have proper anchor bolt holes for attachment to site foundation.

b. Boiler feed pump is sized to accommodate 100% of rated capac-ity with low NPSH required. The pump will be attached to the pump skid which is welded to the structural stand. A quantity of pump(s) is required for a capacity of GPM each (0.002099⫻ pph ⫽ GPM). Discharge pressure to boiler is p-sig. The pump is a centrifugal type and have seals and materials suitable for continuous operation up to 250°F (300°F optional).

Each pump is driven by a HP, 3600 RPM, volt, 3-phase open drip proof (ODP) motor (optional: TEFC). Pumps shall have low NPSH requirements that shall not be exceeded at any time during operation.

c. Boiler feed pump suction piping is included. The suction piping will consist of a gate valve, Y-strainer and expansion joint. The piping will be fit up between the deaerator and the boiler feed pump(s), if shipment clearances allow. Boiler feed pump recircu-lation piping is to be supplied with isorecircu-lation valves and orifice plates.

d. A control panel is to be furnished completely wired, tested, and mounted on the stand. The enclosure is Nema 4 (Nema 12 op-tional). Internals included flange mounted main breaker, fused control power transformer, motor fuse protection, motor starters with overload heaters, hand-off autoselection switch and ‘‘on’’

pilot lights. Panel is capable of housing up to four pump starters.

e. Optional: A bridle piping assembly is supplied prefit up to the deaerator tanks bridle connections. The bridle can be tapped for any customer usage.

14. Any deviations from, or exceptions to, the above specifications must be clearly stated in bid; otherwise, bidder will be expected to deliver equipment exactly as specified.

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