Evaluation of Ceramic Coatings for Protection of Piping in High-Temperature, High-Pressure Black Liquor Gasifiers Jim Keiser, James Hemrick, Edgar Lara-Curzio, Cam Hubbard Metals and Ceramics Division Oak Ridge National Laboratory Bill Headrick University of Missouri - Rolla

G Euro Objective Of Evaluation Of Ceramic Coatings For Protection Of Piping In High-Temperature, High-Pressure Black Liquor Gasifiers Project Identify at least one ceramic/refractory material that has the appropriate thermal conductivity, smelt corrosion resistance and thermal shock resistance to serve as a thermal and chemical protective layer on a water-cooled metal tube in a high-temperature, high-pressure black liquor gasifier

G Euro This Project Has Seven Tasks Evaluate commercially available refractory coatings prior to and following exposure to molten smelt Use thermochemical modeling to identify other refractory or refractory/metal tube combinations Expose the most promising refractory coatings in a test system that simulates the actual conditions Conduct search of non-commercial and experimental materials Select the most promising materials based on exposures and modeling Expose refractory-coated 3 tube panel in gasifier or rotary test furnace Prepare final report identifying at least one suitable coating

G Euro The Arrangement Considered By Both Chemrec AB And B&W Utilizes A Helically Coiled Metal Tube

G Euro The Cooling Screen Will Employ A Refractory Coating To Protect The Tube And Limit Heat Transfer

G Euro Cooling Screen Details Screen will be constructed of helically coiled tubing that is connected by a membrane and has studs or antlers to hold the refractory in place Tubing - 45 mm OD, carbon steel or composite tube Membrane - 25 mm wide Water pressure - 32 bars (~465 psi) Water velocity - 2 to 2½ m/s

G Euro Smelt Level Ar gas Cooling air Heating elements Heating elements thermocouple graphite alumina mullite coating cylindrical steel tube resistively heated cylindrical furnace steel Details Of Preliminary Design Of Refractory Coating Test System

G Euro Summary Search for potential refractory coatings is in progress Design of finger test system is completed and components ordered Proprietary Information Agreements have been opened with Chemrec AB and Babcock Borsig Power Summary of Babcock Borsig Power studies of refractory coatings has been received at ORNL Successful completion of project would identify material to make cooling screen concept practical