Cover Story • P1

S$2.00

Q2April - June2008

MICA (P) 038/01/2008

Superheated steam is hotter and contains more energy than saturated steam. That might sound like a good thing, but it can be a headache in many common applications. We explain why that is and how to get around the issue.

Where is superheated steam used?Superheated steam is at a temperature higher than the saturation temperature for the steam pressure. It is mainly used in power generation plants, where it is more thermodynamically efficient than saturated steam at providing the driving force for turbines. Superheated steam is also very dry, so there are no water droplets to cause friction or erode the turbine blades. Other advantages include higher acceptable pipeline velocities and no condensate in the pipework once the plant is up and running.

– The Hot StuffSuperheated Steam

fi

VISIT YOUR NEAREST SPIRAX SARCO TODAY!Whether it is for some advice or a discussion on optimising your steam plant, you are

most welcome to visit any of our Spirax Sarco offices and approved distributors.

With over 40 Spirax Sarco trained professionals in this region ready to volunteer their expertise and services, we are confident that you will find the consultation with us

greatly rewarding and beneficial to your company.

Website: www.spiraxsarco.com/sg Email: spiraxsin@sg.spiraxsarco.com

fi

Spirax Sarco Pte Ltd(Hong Kong Branch)

Unit 1507, 15/F, ProsperityCenter, Chong Yip Street,

Kwun Tong, Kowloon,Hong Kong

Tel: (852) 2754 9828Fax: (852) 2754 3660Contact: Alfred Wong

E-mail: sales@spirax.com.hk

HO

NG KONG

Spirax Sarco Pte Ltd (Philippines Branch)

Natividad Building2308 Chino Roces Ave Ext

Makati City, Philippines

Tel: (63) 2812 8654Fax: (63) 2812 8673Contact: Ian AplinE-mail: sales_ph@

sg.spiraxsarco.com

THE P

HILIPPINES

Spirax Sarco Vietnam Rep Offi ce

64 / 22 Pho Quang, Ward 2Tan Binh Dist, Ho Chi Minh City

Vietnam

Tel: (84) 08 9974324Fax: (84) 08 4086909

Contact: Nguyen Thanh HaiE-mail: spiraxsarco@

hcm.vnn.vn

VIET

NAM

Spirax Sarco Rep Offi ceJln Zeni No. 4

Mampang ParapatanJakarta 12790, Indonesia

Tel: (62) 021 797 3332Fax: (62) 021 798 2156

Contact: Cosner TambunanE-mail: spiraxsarco.jkt@

petrologmum.co.id

INDONESIA

PT Petrolog Multi Usaha MandiriJln Zeni No. 4

Mampang ParapatanJakarta 12790, Indonesia

Tel: (62) 021 790 1480Fax: (62) 021 798 2156Contact: Budi Setiawan

E-mail: bsetiawan@petrologmum.co.id

PT Centrindo PalmaxBlok.F No.2-3 Kompleks

Brayan, Prima JI. KL. YosSudaruso, Tanjung Mulia

Medan, Indonesia

Tel: (62-61) 6642784-6642785Fax: (62-61) 6642786

Contact: SugiantoE-mail: sales@centrindo.com

Spirax Sarco Pte Ltd(Regional Offi ce)

464 Tagore Industrial AvenueSingapore 787833

Tel: (65) 6 349 0480Fax: (65) 6 459 6854

Contact: Kwek Chin LeongE-mail: KwekChinLeong@

sg.spiraxsarco.com

SINGAPORE

⁄

Cover Story • P2 Spirax Happenings • P3

Spirax Sarco’s inaugural Regional Sales Conference held on 17 – 19 January 2008 at the Orchid Country Club has been a big success with active participation from the delegates.

The objective in organizing this conference is to allow sales personnel within our regions (Singapore, Philippines, Hong Kong, Indonesia and Vietnam) to come together to :

• Share and learn from each other’s experiences

• Broaden knowledge and insights• Build Spirax culture and bond relationship

The theme for this conference is: • Striving Towards Excellence – from Good to

Great !

The program has been planned to challenge the participants’ physical and mental well-being. This includes team building activities, presentations, role plays and workshops that lead us to achieving the theme and objective.

The two-day conference helped build our sales engineers to become more technically driven and customer-oriented. We have strengthened our capability in providing you, our valued customers, total customer satisfaction via our knowledge, products and services.

continue from page 1What disadvantages does it have?Outside power generation, most steam applications are about efficient heat transfer and this is a problem for superheated steam. By far the biggest heat transfer occurs at the moment when the steam condenses, but superheated steam needs to cool before it reaches the saturation point where condensation can take place. Saturated steam therefore offers higher heat transfer rates, so heat exchange equipment can be smaller and cheaper.

In addition, the higher temperature superheated steam may sometimes damage sensitive equipment and this means more expensive, higher specification equipment is needed. The high temperatures can also cause product quality problems.

Why might I have superheated steam on my site?Some sites raise superheated steam to generate their own power, using either primary fuel or waste. This is becoming more common with the increasing popularity of combined heat and power schemes. If superheated steam is available, it makes economic sense to desuperheat some of it and use it for process applications.

It’s usually sensible to distribute the superheated steam to remote points in the plant before cooling it down. This helps keep the steam dry, especially if the point of use is a long way off.

What can I do about it?Desuperheaters can cool superheated steam down to any temperature above the saturation point, although the most common target is 3ºC above saturation. Some desuperheaters are heat exchangers that use indirect contact between the cooling medium and the steam. The direct approach is far more common, however, since it typically provides a more compact, cost-effective solution.

Direct desuperheater systems usually comprise a water control valve, a steam atomising valve and a desuperheater nozzle that mixes a fine spray of cooling water into the superheated steam. The water cools the steam as it vaporises.

Superheated Steam – The Hot Stuff ⁄

The higher temperature superheated steam

may sometimes damage sensitive

equipment and this means more expensive,

higher specification equipment is needed.

Spirax Sarco Singapore - Inaugural Regional Sales Conference

Product Highlights • P4 Product Highlights • P5

The APT Packaged Units comes in 3 different models namely

• APT10-PPU An APT10-4.5 automatic pump trap with

SG iron body and cover and stainless steel internals, mounted on an adjustable base, complete with ancillaries for use with pressure up to 4.5 barg. Designed for closed loop systems.

• APT14-PPU An APT14 automatic pump trap

with SG iron body and cover and stainless steel internals, mounted on an adjustable base, complete with ancillaries for use with pressure up to 13.8 barg. Designed for closed loop systems.

Product Features Customer’s Benefi ts

ß Low profi le

ß Suitable for heat exchangers with condensate discharge close to ground level. This allows the condensate to gravitate into the pump.

ß Adjustable Feetß For stability on uneven

surfaces

ß Inbuilt Receiver ß Ease of installation

ß Reducer spool pieces availableß Easy connection to the

system pipe-work

ß Flanged and welded construction

ß Reduces possible leaks

ß Modular design ß Easy to maintain

ß Range of sizesß Can be tailored to suit wide

range of applications

€APT14-PPU

⁄APT10-PPU

Spirax Sarco Automatic Pump Trap (APT) range has been designed to remove condensate from steam heat exchangers and process plant under all operating conditions, and forms an integral part of the condensate removal process.

Since its launch, this compact condensate drainage system has been well received by the market. As part of our continuous effort to provide customers with total solutions and services, we are pleased to introduce the new Spirax Sarco Automatic Pump Trap (APT) Packaged Units.

• APT14HC-PPU An APT14HC (Higher Capacity) automatic pump trap with SG iron body

and cover and stainless steel internals, mounted on an adjustable base, complete with ancillaries for use with pressure up to 13.8 barg. Designed for closed loop systems.

The APT Packaged Units have been designed to offer the following features and benefits.

Cool Tips For Hot Issues • P6 Dear TC • P7

Cut your carbon footprint and energy bills

‹Steam Mains ‹Boiler Pan ‹Vacuum Breakers

Studies have shown that CO2 emission is the main contributor to global warming. People around the world are anxious to ‘do their bit’ to minimize this carbon footprint to save the planet.

Experts from Spirax Sarco have identified some key areas for carbon emissions reduction which can be easily implemented and are cost-effective at the same time.

Are you ready to contribute ‘your bit’ too?

1. Switch to heating on demand Hot water storage results in significant heat losses. Consider replacing storage

systems with plate heat exchangers that use steam to provide hot water on demand. They are extremely responsive and their compact size leads to heat losses from their surface that are significantly lower than those of hot water storage vessels performing the same duty.

2. Recover all condensateCondensate contains up to 20% of the energy in the steam from which it came. Returning hot condensate to the boiler feedtank typically recovers about half this energy, while the rest can be recovered by installing a flash steam vessel or pressurized condensate return system. Condensate return schemes also save money on water, treatment chemicals and effluent charges.

3. Install automatic boiler blowdownAll steam boilers need to be purged by blowdown. The key is to remove only enough water to maintain the Total Dissolved Solids (TDS) content at an acceptable level. Dumping any more is a waste of energy, treated water and chemicals. An automatic TDS blowdown controller monitors TDS build-up in the boiler and opens the blowdown valve only as required.

4. Focus on feedback conditionsLess fuel is needed to produce steam from hot feed water. Using returned condensate to raise the feed temperature by 6ºC gives a fuel saving of 1%. Ideally, feed water should be maintained at 90ºC.

Q I am an Engineer, by profession, in a textile mill in Indonesia. I am a regular reader of the Steam Express magazine and user of Spirax products. I have the following question for Dear TC.

1. What is a Vacuum Breaker? 2. Where is a Vacuum Breaker used at and what are the advantages in

using it? 3. Is Vacuum Breaker a preferred choice as compared to an Air

Vent?

S.V Ramanathan, PT Bitratex Industries - Semarang, Indonesia

A Vacuum Breaker admits air from the surrounding into a system or equipment when its pressure is less than atmospheric pressure.

In temperature controlled applications, the steam space can be at partial vacuum when operating at low loads. By admitting air in, it ‘breaks’ the vacuum hence the name Vacuum Breaker.

This aids in the removal of condensate by steam traps discharging by gravity at atmospheric receiver or drain. The steam trap must be fitted below the equipment or system with sufficient static head.

The function of the air vent is very different from a Vacuum Breaker. An Air Vent removes air in the steam system.

Vacuum Breaker is commonly found in applications like the Boiler Pan and Steam Mains (see illustration below).

In this column, we feature customers’ questions and answers provided by our Technical and Training Manager, Mr Chng Poh Beng.

Simply send your questions marked “Dear TC” to StephanieCheong@sg.spiraxsarco.com or to fax number 65-6459 6854. Kindly indicate if you do not wish to have your name and/or your company’s name published. We reserve the right to edit the questions and not to publish them. If your question is published in Steam Express, you will receive a corporate gift.

In this column, we feature customers’ questions and answers provided by our

Simply send your questions marked “Dear TC” to StephanieCheong@sg.spiraxsarco.com or to fax number 65-6459 6854. Kindly indicate if you do not wish to have your name and/or your company’s name published. We reserve the right to edit the questions and not to publish them. If your question is published in Steam Express,