Heating Equipment and System - Flocontrol...4 Gas Heater What is an indirect Heater An indirect heater is an oilfield terminology for a vessel complete with: a firetube (which is usually

A Long Experience in Energy Equipment and one Goal:

Heating Equipmentand System

The Customer ’s sa t i s fac t ion .

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VALVITALIA SpA, Valvitalia Systems Division is asuccessful Company that for a hundred years hasbeen dedicating its activity to the design and production of Natural Gas Treatment Equipment forindustrial, civil and power generation applications,offering a wide range of products to give a highdegree of customisation and an extremely high standard of quality and service. The company’s attainment of prestigious certifications underlines alevel of overall quality unmatched in the sector: notjust extremely high standards of quality and service,but research and innovation in terms of technologicaland management expertise.

A complete range of gas heater is part ofValvitalia Systems Division production:

• Water/ Steam Heat exchanger• Gas Heater• Electric Heater • Oil Diathermic Heater• Performance Heater

Valvitalia Systems Division activitiesincludes: developing, design, manufactu-ring and supplying of gas heater with vertical and horizontal configuration;design codes:

• ASME Sec. VIII;• BS• AD Mehrblatt • U Stamped• PED• Others upon request

VALVITALIA reserves the right to change design, specification and materials without notice

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Shell and tubesHeat ExchangerHeat exchangers are designed for heating naturalgas, air, propane and other non aggressive gases. Theyare designed to compensate the Joule-Thompsoneffect during a gas expansion, in order to avoid thehydrates formation potentially dangerous in gastreatment and reduction station. The working principle is based on heat exchange by conductionbetween the heating fluid (hot water or steam) andthe gas to be expanded. Heat exchangers guaranteea wide exchange surface in order to keep high thermal efficiency.

Design advantages

• Standard design units are available for a wide rangeof temperatures, pressures and flow rates

• Customised features upon customer request• Wide range of materials• Heating fluids: hot water and steam• Low Pressure Loss• Large surface for high thermal efficiency• Low Maintenance costs• No floating parts are inside the equipment, which

will avoid malfunctions and maintenance costs.

Features

• Maximum working temperature: up to 300°C• Gas nozzle connection: from ANSI 150

up to ANSI 900• Water/steam nozzle connection:

PN16, ANSI 150,ANSI 300• Power rating: from 7.000 kcal/h

up to 5.000.000 kcal/h• Low cost internal inspection: with the inspectable

model it is possible to check and verify the inter-nalsection of the vessel with a low service cost.


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Gas Heater

What is an indirect HeaterAn indirect heater is an oilfield terminology for avessel complete with: a firetube (which is usuallyfired by natural gas), a fluid around the firetube(which is usually water) and, immersed in the fluid, a coil containing the fluid to be heated. The waterbath around the firetube is heated directly by havingcontact with the firetube and the coil containing thefluid to be heated is immersed in this hot water bath.Because there is an intermediate step of heat transfer between firetube and coil, the heater derivesits oilfield terminology of “indirect heater”.

Use of the indirect HeaterNormally the natural gas is produced at high pressures ranging from 1,500 psi up to 3,000 psi and it’s usually transferred to sale gas lines that operate at 1,200 psi and below. The indirect heater is often employed to supply heat to a gas stream that is being expanded from some elevated pressure(well head) to some intermediate pressure (intermediate production equipment) or to theactual sale line pressure. Heat supplied is used tocompensate for the Joule-Thompson effect of the gasthrough expansion.

Why an indirect HeaterIt is to be found in an economic justification. The fluid carrying coils are operated at a maximum pressure of 3,000 psi. (depending on the customerrequirements), whereas the shell of the indirect heater containing the heat transfer medium (water)is operated usually at atmospheric pressure, or at avery little pressure above it, therefore it’s required athin wall vessel for the heater shell. In addition, alsothe firetube needs withstand only the atmosphericpressure plus a few pounds. It would be prohibitivefrom several standpoints to attempt to make firetube to withstand the pressure of 3,000 psi aswell as the heater shell itself; thus the creation of theindirect type heater with fluid carrying high pressurecoils immersed in an atmospheric pressure waterbath heated by a firetube operating close to theatmospheric pressure.


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Features AvailableRemovable Firetube

Removable Tube bundle

Large firetube combustion volume per square foot

of firetube area

Quality fabrication

X-ray and stress relieving facilities

Automatic control, regulation and safety systems

suitable to operate also without electric power.

High Performance and High Efficiency

The high pressure fluid is introduced to the heatingunit through a choke located at the heater inlet, andthe expansion takes place immediately inside theheater in the water bath. Then, as the fluid passesthrough the steel coils, it’s raised to the desired outlet temperature suitable to compensate theJoule-Thompson effect during the expansion. Thesteel coil, which is subject to the well head operatingpressure, is subject further to corrosion by the fluidcarried within the steel pipe as well as erosion caused by the high velocity of the fluid itself. In timethe combination of corrosion and erosion takes itstoll in wall thickness of steel pipe.

A most frequent application

API 12 KASME VIII

Designed and manufactured inaccordance to:


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Electric Heater

Performance HeaterGas Fuel Performance Heater consists of two stacked shell and tube heat exchangers in series. Theheat exchangers are single pass fixed tubesheettype, and include expansion bellows on the shell. A growing number of combined-cycle power plantsare incorporating performance heater as a means ofimproving overal efficency. The Heater improves gasturbine efficency by reducing the amount of fuel needed to achieve desired firing temperature (generally inthe range of 185°C). For fuel heating tobe a viable method of performance enhancement,feedwater has to be extracted from the heat recovery steam generator at an optimum location.Boiler feedwater leaving the intermediate pressureeconomizer is commonly used. Using gas fired, oil-fired, or electric heaters for performance gas fuelheating will not result in a power plant thermal efficency improvement.

In all the cases in which it's required a quick heatingand eletric power is available, an electric heater is amandatory choice.

Oil Diathermic HeaterThe diathermic oil systems use a diathermic fluid as carrier for heat transfer. The main characteristic of a diathermic oil (mineral or synthetic) is the high boiling temperature (more than 350° C) at standard atmospheric pressure: then it is possible to reach high temperatures without using high pressure values.


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Spare PartsTGT Quality is completed by the after sale assistance and a complete organisation which focus its own activityon care, technical support and spare part requests of the customer. For further information please contact theSERVICE DEPARTMENT:

Tel. +39 049 9199653 - Fax +39 049 9125455 - E-mail: [email protected]

3-way valve

Heat exchanger on skid Gas Heater ready for shipment

Water boilers


A Long Experience in Energy Equipment and one Goal:

The Cus tomer ’s sa t i s fac t ion .

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Padova Plant.

VALVITALIA S.p.A. - Systems DivisionVia Campolongo, 97 - 35020 Due Carrare (PD) - Italy

Phone: +39.049.9199611 - Fax: +39.049.9125455E-mail: [email protected]

Web site: www.valvitalia.com

Heating Equipment and System - Flocontrol...4 Gas Heater What is an indirect Heater An indirect heater is an oilfield terminology for a vessel complete with: a firetube (which is usually

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