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Show 2.0 Downtime (con't) 2.2 The Shell LFR system has the advantage of being installed at the 'tailend' of the furnace heat recovery system ... flue gas temperature around 4000 F and therefore can be erected complete with the ammonia injection system alongside the furnace prior to the shutdown period. In addition, prior to shutdown, an induced draft fan and grade mounted stack can also be installed. On shutdown, the ducting from the existing furnace stack to the SCA would be erected. Installation would be easily accomplished within the two week window. 2.3 Major burner retrofits and the installation of conventional SCAs retaining the same efficiency of the furnace prior to revamp will not be accomplished within the normal two week downtime period and accordingly the project TIC and schedule will be affected. 3.0 Field Labor Costs/Project Costs 3.1 The field labor costs in the Los Angeles basin are among the highest in the United States. The manhour rate including small tools and equipment is an average of $50/manhour. As such, the construction costs are a high proportion of the project TIC and therefore the choice of NOx reduction technology must be influenced by its installation costs. 3.2 A breakdown of the project costs to install a single conventional SCR as a common NOx reduction system for three furnaces is shown in paragraph 3.4. To achieve a flue gas temperature of around 6800 F, the steam generating coils were removed from the convection sections of the three furnaces. An air preheat system was installed to retain the furnace efficiency of around eighty-eight (88%). 3.3 As a comparison, the project costs to install a Shell LFA system are also shown in paragraph 3.4. The ability of the LFR to handle a flue gas temperature of around 4000 F precludes the need for forced draft burners, air p eheater, removal of steam coils and the extensive control and instrumentation systems that have been "forced" on the end user by the inclusion of the air preheat system. 9 |
