Roth Low Silhouette

TRAY DEAERATORSBoiler Feedwater HeaterCapacities to 50,000 lb/hr

Roth Low Silhouette

TRAY DEAERATORSBoiler Feedwater HeaterCapacities to 50,000 lb/hr

The Roth Solution:Preheated, deaeratedconditioned waterreduces operating cost.Roth deaerators areassembled with Roth pumpsrequiring only one- or two-footNPSH operating at 1750 rpm

Roth Pump Company1 . 888 . 444 . ROTHRoth Pump Company1 . 888 . 444 . ROTH

Model RDTV-150-5-1-2vertical tray typedeaerator

Why deaerate boiler feedwater?There are many advantages to deaeratingwater prior to boiler input, but they all boildown to reduced cost operation.• Water is heated during deaeration to near

the temperature of the boiler water, thusminimizing the risk of thermal shockdamage to a high-value boiler system.

• The deaerating process removes non-condensable gases (oxygen and carbondioxide) which tend to act as insulatorsinhibiting the transfer of heat within theboiler.

• Removal of oxygen and carbon dioxidereduces corrosion within the boiler andpiping, extending the life expectancy of thesystem and reducing maintenance cost.

• Higher temperature feedwater reduces thechance of pressure drop within the boilerwhich can occur when cold water is added.

• Recycling of steam from vents and flashsteam from traps that would otherwise bevented to the atmosphere can result inappreciable energy savings.

• Mechanical deaeration by a feedwaterdeaerator can cut the amount of chemicalconsumables used for water conditioningfor a continuing operating cost saving.

Choosing the right deaeratorRoth tray type deaerators are generally con-sidered the superior choice for most applica-tions. These units use stainless steel for allinternal surfaces which come in contact withundeaerated water.

Residence time for undeaerated waterinside a tray type deaerator is longer, provid-ing more efficient deaeration, particularlywhere wide load swings occur. A large diam-eter hinged door affords easy access to inter-nal trays and spray tubes for maintenance andreplacement.

Although tray type deaerators require alarger initial investment, the benefits in effi-ciency and reduced cost of maintenance tendto pay for themselves quickly.Pump selectionRoth deaerators use low NPSH pumps. Mostpumps selected require only one foot NPSHoperating at 1750 rpm. By using these pumps,the overall height of the unit can be lowered.This can save on construction cost.

Roth tray type deaerators condition feedwater to 0% CO2 and only .005 cc/l of oxygen

Reduce costs and improve system efficiency bypreheating and deaerating boiler feedwater

Model * = # of RDTV- RDTV- RDTV- RDTV- RDTV- RDTV- RDTV- RDTV- RDTV- RDTV-pumps 150-5-1-* 150-10-2-* 150-15-3-* 150-20-4-* 150-25-5-* 150-30-6-* 150-35-7-* 150-40-8-* 150-45-9-* 150-50-10-*

Capacity Lb/h 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000 50,000(kg/h) (2,268) (4,536) (6,804) (9,072) (11,340) (13,608) (15,876) (18,144) (20,412) (22,680)

Boiler hp 145 290 435 580 725 870 1,015 1,160 1,305 1,450(kW) (1,422) (2,844) (4,267) (5,686) (7,107) (8,529) (9,950) (11,372) (12,793) (14,214)

Storage 100 200 300 400 500 600 700 800 900 1,000gallons (l) (378) (757) (1,135) (1,514) (1,893) (2,271) (2,650) (3,028) (3,407) (3,785)

Dimensions A. Overall 66 66 66 84 84 84 96 96 96 96in (cm) length (168) (168) (168) (213) (213) (213) (244) (244) (244) (244)except as B. Overall 54 54 54 72 72 72 84 84 84 84noted width (137) (137) (137) (183) (183) (183) (213) (213) (213) (213)

C. Overall 83 99 113 108 116 124 125 131 141 147 height (211) (251) (287) (274) (295) (315) (318) (333) (358) (373)D. Tank 42 42 42 60 60 60 72 72 72 72

diameter (107) (107) (107) (152) (152) (152) (183) (183) (183) (183)E. Overflow 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb

trap 2 NPT 2 NPT 2 NPT flange flange flange flange flange flange flangeF. Tray access 20 20 20 24 24 24 24 24 24 24

door dia. (51) (51) (51) (61) (61) (61) (61) (61) (61) (61)G. Pump 3”, 150 lb 3”, 150 lb 3”, 150 lb 4”, 150 lb 4”, 150 lb 4”, 150 lb 6”, 150 lb 6”, 150 lb 6”, 150 lb 6”, 150 lb

suction flange flange flange flange flange flange flange flange flange flangeH. Pump bypass 2 NPT 2 NPT 2 NPT 2 NPT 2 NPT 2 NPT 3 NPT 3 NPT 3 NPT 3 NPTI. Hi-temp

2”, 150 lb 2”, 150 lb 2”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lbcondensateflange flange flange flange flange flange flange flange flange flangereturn

J. Steam 4”, 150 lb 4”, 150 lb 4”, 150 lb 6”, 150 lb 6”, 150 lb 6”, 150 lb 8”, 150 lb 8”, 150 lb 8”, 150 lb 8”, 150 lbconnection flange flange flange flange flange flange flange flange flange flange

K. Water 2”, 150 lb 2”, 150 lb 2”, 150 lb 3”, 150 lb 3”, 150 lb 3”, 150 lb 4”, 150 lb 4”, 150 lb 4”, 150 lb 4”, 150 lbconnection flange flange flange flange flange flange flange flange flange flange

L. Base 4 4 4 4 4 4 4 4 4 4height (10) (10) (10) (10) (10) (10) (10) (10) (10) (10)

Control and piping configurations will varydepending upon job specifications and condi-tions. Dimensions are subject to change withoutnotice. Consult factory for certified dimensions.

Legend for drawings

1. Make-up water control2. High level control3. Low level control4. Vacuum breaker5. Temperature gauge6. Pressure gauge7. 1½” NPT vent8. 1” NPT chemical port9. 1” NPT drain10. 1” NPT sample port11. 1” NPT additional port12. Gauge glass

Roth Deaerator Specifications

Sample Specification—Roth DeaeratorDEAERATOR:A. The deaerator shall be a Roth style “RDTV” deaerator which guarantees oxygen removal to 0.005 cc/l (7 ppb) or less and

carbon dioxide removal to a zero measurable level in the effluent throughout all load conditions between 0% and 100% ofrated capacity. The deaeration process will take place in a 5-15 psig steam environment that will heat the water to 228-250°F requiring a pressurized vessel. The deaerator shall be manufactured in strict accordance with the ASME Section VIII,Div. 1 code and bear the ASME stamp for a maximum working pressure of 50 psig at 300ºF. An atmospheric deaerator is notacceptable. A minimum of 1/16” corrosion allowance shall be added to the ASME calculated material thickness forheads and shell and will be noted on the ASME data report (form U-1). The deaerator is to be of the vertical design with avessel of _____” diameter x _____” high setting less than 18” from the floor.

B. The deaerator is to be of the tray type design. Spray type deaerators are not acceptable. Flow of steam shall be such thatthe steam entering the heater first comes in contact with the hottest water which is leaving the last row of trays and thenproceeds upward through the tray stack in a counter-flow fashion. The water to be deaerated will enter the vessel through astainless steel spray tube. The spray tube will disperse water into a 304L stainless steel box that is sealed so that escapinggasses can not come in contact with the vessel walls. The gases escape through a 304L vent condenser pipe on top of thetray box that extends out the top of the vessel. The spray tube directs the water into sections of a 304L stainless steel ventwelded on top of the tray box. The water falls downward from the vent condenser and spreads over the stainless steel traysand, after deaeration, falls into the storage area. The stainless steel (304L) trays will be removable through a minimum 20”dia. hinged tray access door. Each tray shall weigh no more than 30 lbs. for easy handling and inspection and shall be ofwelded construction. Rivets are not acceptable. The deaerator will be designed so that undeaerated water will only comeinto contact with stainless steel components.

C. The tray type deaerator is to be fully trimmed by the manufacturer including the following items:1. Low Level Control: An external float type control is to be supplied to monitor a low level condition. A low level shall

ring an alarm bell and light a red light on the control panel notifying the operator. The control shall also shut off thedeaerator pumps protecting them from harm.

2. High Level Control: An external float type control is to be supplied to monitor a high level condition. A high level shallring an alarm bell and light a red light on the control panel notifying the operator. The high level control shall beactivated before the water reaches the overflow level.

3. Overflow Trap: A mechanical self-contained external float type overflow trap shall be supplied to overflow the water inthe storage area before flooding the deaerator. The overflow trap body is to be constructed of cast iron. Inside the body,a stainless steel ball float automatically operates a double-seated brass valve. The cast iron body is to be boltedtogether in order to take apart for inspection/maintenance of the valve assembly. A butterfly valve is to be suppliedbetween the deaerator and the trap for inspection without having to shut down the deaerator.

4. Make-up Water Assembly: An electric water level controller and make-up water valve is to be supplied to monitor thelevel of water storage in the deaerator and add make-up water when necessary for continued operation. The level toactivate the water valve shall be field adjustable to match desirable operating conditions. The water valve shall besuitable for operation with a pressure differential of up to 150 psi. The valve shall default to a closed position when de-energized and be a modulating or slow closing valve in order to reduce or eliminate water hammer. The valve shall befactory piped with a 3-valve bypass assembly and strainer.

5. Pressure Reducing Valve: A self-contained pilot operated valve shall be supplied when necessary to reduce theavailable steam pressure to the operating pressure of the deaerator (5-15 psig). The valve is to be shipped loose forfield installation. Relief valve(s) acceptable for ASME service shall also be supplied. The relieving capacity of thevalves shall be greater than the maximum capacity of the pressure reducing valve and set to relieve at 50 psig.

6. Vacuum Breaker: A vacuum breaker is to be supplied to release any vacuum in the deaerator during operation.7. Vent Valve: A manual valve shall be supplied to vent the deaerator. The valve is to have the ability to be field adjust-

able with a 1/8” drilled orifice to avoid complete shut off capability.8. Drain Valve: A gate valve is to be supplied and sized the same diameter as the drain connection and be supplied by

the manufacturer.9. Misc. Gauges: A pressure and temperature gauge shall be supplied and installed by the manufacturer. The gauges

shall be sized suitable for the operation and design range of the deaerator and follow any ASME or local codes andrequirements. A gauge glass shall be supplied and installed to cover the water level range from low level to overflowlevel. The gauge glass shall be protected from getting hit by outside objects and be so mounted to protect from gettingbroken.

10. Pump Suction: The pump suction shall be sized based on a velocity 3 ft/sec of twice the deaerator capacity. Aseparate gate valve, strainer, and flexible connector shall be supplied for each pump.

Roth Tray Type Deaerators

Roth tray typedeaerators removeCO2 from feedwatercompletely and reduceoxygen to .005 cc/l.Available with capaci-ties up to 50,000pounds per hour, Rothtray type deaeratorscome completelypackaged with allstandard accessoriesand trim. Internalsurfaces which come incontact withundeaerated water arestainless steel.Undeaerated water

and corrosive gases never come in contact with thedeaerator shell.

A complete line of boiler feed pumps and controlpanel packages is available. Custom engineeredsystems and larger than standard units are alsoavailable. Consult the factory.

Roth Deaerator Pumps

Roth pioneering—The Roy E. Roth Company has been a pioneer inthe industry for over 45 years by developing NPSHdata on its products for use by engineers. In 1954,it was the first manufacturer of regenerative turbinepumps to publish NPSH data on individual models.At that time, the Roy E. Roth Company developedand published the first NPSH curves on regenera-tive turbine pumps in a format now used throughoutthe industry. It is the only manufacturer of regenera-tive turbine pumps today with numerous patentsdesigned to improve the NPSH characteristics of itspumps.Roth one-foot NPSH pumps—The Roth Pump Company, the manufacturingsuccessor, is the only pump manufacturer in theworld today that offers a line of pumps with fullperformance at one-foot NPSH at speeds of both1750 and 3500 rpm in a range of differential headsup to 600 feet TDH and capacities up to 190 GPM.

All Roth pumps in this bulletin are guaranteed todeliver the full-rated capacity of water to the boiler.

Roth one-foot NPSH pumps were originallydeveloped to pump 230° F deaerated water fromthe deaerator to the boiler. Now the original designhas been improved to include high-capacity modelsfully functional at one-foot NPSH.Standard equipment—• All deaerators are constructed to ASME Section VIII, Div. 1 for

50 psig, 300° F• Easily accessible manways and access doors for internal

inspection and servicing• Standard storage capacity: 10 minutes of operation. Optional

larger storage capacities available• Structural steel stand and pump platform• High and low level control alarms• External make-up water level control (field adjustable)• Make-up water valve with three-valve bypass• Pilot operated steam pressure reducing valve (when required)• Relief valve sized for full output of the pressure reducing valve

set at 50 psig• Manual vent valve(s) with properly sized orifice in gate• Vacuum breaker• Pressure gauge and thermometer• Overflow trap sized to relieve full capacity of deaerator• Full range sight glass• Drain valve

Non-condensable gases (O2, CO 2)Deaerated waterCondensate return & water make-upSteam

3070.40.2603 © 2000, Roth Pump Company Printed in USA

Roth Pump CompanyP.O. Box 4330, Rock Island, IL 61204 U.S.A.Toll-Free: 1.888.444.ROTH (1.888.444.7684)

309.787.1791 . Fax: 309.787.5142 www.rothpump.com

Contact your Authorized Roth Representative Today!