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What is it?

Condensate Recovery Systems are specically designedequipment to recover condensate rom steam

installations in order to maximise their overall energyeciency.

Condensate Recovery Systems equipment are

considered to include the ollowing:

Condensate Recovery Vessels

These are designed to handle hot condensate, which is

commonly returned or use as boiler eedwater.

Steam TrapsAre devices which allow the

discharge o condensatewithout the release o steam

rom steam lines in a steam andcondensate system.

Deaeration Tanks

Remove oxygen and otherdissolved gasses rom steam

boiler eedwater to reduce

corrosion and improveeciency in the steam system.

How does it work?

A Condensate Recovery Unit is avessel which receives condensate

rom all practical points in aprocess plant or heating system

where condensate is produced.The vessel stores the condensate

and mixes it with resh make upwater prior to it being used as

boiler eedwater.

Steam Traps are essentially valves which diferentiatebetween steam and condensate. They open to discharge

condensate, but do not allow steam to escape. A steamtrap has three important unctions:

To remove the condensate ormed either within the

steam pipework or within the process equipment. To prevent large amounts o steam escaping.

To enable any air and other gases in the system toescape.

In a Deaeration Tankboiler eedwater is trickled downover perorated plates, low pressure steam is passed

upwards to strip of oxygen and other dissolved gasses.The steam and gas rise to the top o the tank and are

then vented to atmosphere.

In another type o deaeration tank low pressure steam isinjected into the stored eedwater again the steam and

gas rise to the top o the tank and are then vented to

atmosphere. Depending on the size o the installationthe deaeration tank also acts as the eedwater storagetank.

Technical GuideCondensate Recovery

System

Figure 1. Condensate

Recovery Unit

Figure 2. Ball Float Steam Trap

(Image courtesy o Spirax Sarco)

Figure 3. Dearation Tank

(Image courtesy o Spirax Sarco)

Dearation Tank(Image courtesy o Amarinth)

Steam Trap

(Image courtesy o Spirax Sarco)

(mage courtesy o Spirax Sarco)

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What are the energy saving benefts?

Installing energy ecient technologies on an existing

standard steam and condensate installation is a meanso improving boiler perormance without having to

replace the entire steam boiler or system.

Typical Energy savings or each o the technologies arelisted below:

Condensate Recovery Vessels

68%reductioninfuelcosts Typicalpaybackperiods1-4years

Reducedcarbonemissions

Steam Traps

2-3%reductioninfuelcosts Typicalpaybackperiods2-4years

Shorterstart-uptimes Reducedcarbonemissions

Deaeration Tanks

1-2%reductioninfuelcosts

Typicalpaybackperiods4-6years Reducedriskofcorrosionfailures

Reducedwatertreatmentcosts Reducedcarbonemissions

Issues to consider when choosing a Condensate

Recovery System:

Condensate Recovery Vessels

a) Where very long pipe runs would be requiredto return condensate to the boiler house,

condensate recovery may not be viable inenergy terms.

b) Even where long pipe runs make energy recoveryuneconomic condensate recovery may still be

viable when the water treatment costs andwater replacement costs are taken into account.

c) I the condensate can be contaminated bycontact with process materials it can cause

ouling o the heat transer surace in the boiler.

In such circumstances the condensate should

be passed through a heat exchanger to recover

heat energy.

Steam Traps

a) It is essential to select the correct size and typeo trap or both starting and normal operating

loads. It is particularly important to size the trapto accommodate the increased condensate

capacity at start-up, an incorrectly sized trapmaynotoperatecorrectlyandstart-uptimesare

likely to increase.

b) Trap sizing is based upon - normaloperationalload

- (kg/hofcondensate) - start-upload

- (kg/hofcondensate) - Condensatetemperature(max/min)

- SteamPressure(max/min) - Backpressurethetrapmustoperateagainst

c) Consult a reputable manuacturer or specicdesign and installation inormation.

d) All types o steam trap ail i they are not properlymaintained or protected. The best method or

ensuring correct trap operation and eciency is aplanned preventative maintenance programme.

e) Failure monitoring o steam traps noties userwhen a steam trap has ailed.

Deaeration Tanks

a) Sucient space has to be available within or

near to the boiler house to accommodate thedeaeration tank.

b) Deaeration must be used in conjunction with

other water treatment measures.c) Monitoring o the water condition must be

carried out regularly, automatically or by

sampling.

Energy ecient Localised Steam Generator Systemsare eligible or the ACA (Accelerated Capital Allowance)

and included on the Triple E product register. Moreinormation can be ound at www.seai.ie/Your_Business/

Triple_E_Product_Register/

Wilton Park House, Wilton Place, Dublin 2

Teach Phirc Wilton, Pls Wilton, Baile tha Claith 2T. +353 1 808 2100

F. +353 1 808 2002

info@seai.ie

www.seai.ie

TheSutainableEnergy Authority of Ireland ispartlynanced by IrelandsEU StructuralFunds Programmeco-funded by theIris h Governmentand theEuropeanUnion.