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New boilers or conversion of existing boilers? The boiler and combustion system onboard a turbine tanker is designed for firing heavy fuel oil with diesel as backup. But onboard an FPSO or FSO, the boilers are required to run on gas or crude with diesel as backup. When an existing boiler needs to be modified to become optimised for other fuels than it was originally built for, a boiler survey should be made to determine its fitness for the new operation. Before deciding whether the existing boiler should be converted, the boiler must be inspected. Aalborg Industries’ experienced boiler engineers can make a survey of the boiler to check its condition. Depending on the boiler’s level of maintenance, the conversion of the boiler can vary from replacing a few tubes to an extensive retubing of the boiler and installation of a new superheater. When changing from HFO and diesel firing to gas, crude and diesel firing, a new burner has to be installed. The control system must be changed and new fuel supply lines for the gas and crude must be installed. Double pipe-work, gas detection systems and extraction air systems must also be installed to ensure safe containment of these hazardous fuels below deck in the engine spaces. The answer to the question in the headline is a combination of the total investment for converting the existing boiler or installing a new boiler, keeping the time schedule for the project and ensuring the FPSO’s life length of 20 to 25 years. Quite often the clients choose to install new boilers on deck, keeping the existing boilers in the engine room for back-up. for some of the latest large FPSO projects. A few years ago, a large FPSO pumped up to 100,000 bpd. Today it pumps twice as much, or more. As a result of the trend towards larger FPSOs and the increasing need of steam onboard these vessels, Aalborg Industries have developed an even more powerful version of the MISSION™ D-type boiler. Today, the boiler can be delivered with an internal superheater for steam production up to 120 t/h at 40 barg. The boiler is a result of decades of experience from industrial boilers combined with marine main propulsion boilers and auxiliary boilers. Boiler installation on deck or in the engine room? Some of the boilers we have installed on FPSOs during the years have been placed in the engine room, but most of them have been on the open deck and in hazardous areas. It might sound easier and much less expensive to install the boiler in a safe area engine room, but it is actually quite the opposite. In order to keep the area safe, the gas fuel valves and the burner have to be enclosed and gas detection and extraction systems have to be installed. If the boilers are installed in a hazardous area on deck, the boiler, feedwater tank, combustion system and all other equipment have to be designed for exposure to the weather with carefully selected materials, special painting, insulation with stainless cladding, etc. Instruments and electric motors must have the correct Ex-rating and protection to a minimum of IP 56. A boiler system on deck is quite straight forward. Ex-rated equipment is today generally available at reasonable prices. The price of Exrated equipment is still higher, but the difference is shrinking as the availability of the equipment increases. The total cost for a steam system on deck in a hazardous area is normally lower and the system is less complicated compared to the same system in a safe area engine room. Wide product range In order to meet market expectation, Aalborg Industries have combined the best technologies from our industrial and marine boilers in a new generation of marine boilers. Steam boiler capacities up to 120 t/h MISSION™ D-type up to 120 t/h, 40 bar superheated steam New, more powerful boiler Aalborg Industries’ standard MISSION™ D-type boiler, designed for capacities up to 120 t/h and 18 barg saturated steam has been selected Hot-water boiler capacities up to 30 MW MISSION™ thermal fluid heater capacities up to 20 MW Heat recovery boilers after gas turbines Offshore News is published by Aalborg Industries’ business & product centre for equipment supply to FPSOs and FSOs. Ideas and suggestions for topics are most welcome. Aalborg Industries AB · Riddarplatsen 36, Jakobsberg · P.O. Box 907 · 175 29 Järfälla · Sweden Phone: +46 8 580 243 00 · Telefax: +46 8 580 278 01 · E-mail: stom@aalborg-industries.se For world-wide Aalborg Industries addresses, please check http://www.aalborg-industries.com Contact us Your Preferred Partner

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