Euan Evenson Praxair, Research and Development

Transcription

1 Euan Evenson Praxair, Research and Development

2 Praxair at a Glance A Fortune 300 company with 2015 sales of $11 billion A leading industrial gas company in North and South America and one of the largest worldwide Doing business in more than 50 countries ~26,000 employees One million customers worldwide 2 12/13/2016

3 2015 Sales Breakdown END MARKETS GEOGRAPHIES DISTRIBUTION METHOD Electronics 8% Food/Beverage 9% Healthcare 8% Chemicals 10% Other 8% Manufacturing 24% Energy 13% Metals 17% Surface Technologies 6% Asia 14% Europe 12% South America 13% North America 55% Onsite 29% Other 9% Packaged Gases 28% Merchant 34% Aerospace 3% 3 12/13/2016

4 Praxair - Hot Oxygen Technology CONOx reduces NO x and CO O 2 preheated with small amount of fuel and accelerated through nozzle Fast, hot, gas jet quickly mixes and reacts w/ surroundings Syngas production Syngas from NG or COG Tar/CH 4 reforming in syngas to increase yield HOB producing syngas Highly Reactive Fly ash carbon burnout for reuse/metals recovery 4 12/13/2016

5 Hot Oxygen Principles Oxygen U.S. Patent 5,266,024 Fuel Oxygen Jet Flue gas entrainment Oxygen jet issues from thermal nozzle with unique characteristics: High velocity (typ. > 750 m/s) induces recirculation and mixing High concentration of radicals (important for reaction kinetics) Drives lower temperature oxidation reactions vs. higher temperature combustion reactions in gases containing hydrocarbons Demonstrated reactivity and kinetics due to injection of highly reactive gas 5 12/13/2016

6 What is CONOx? CONOx is an application of the Hot Oxygen technology in which an oxygen lance injector is placed in the hot flue gas duct leaving the FCC regenerator of a refinery The CONOx lance produces preheated oxygen to destroy CO and NOx precursors (NH 3 and HCN) with little or no generation of NO x CONOx is a low capital, variable operating cost solution for reducing FCC NOx by up to 60% In partial combustion units, CONOx reduces NO x precursors and may enable FCCU operation at higher CO while maintaining low NO x emissions In full combustion units, CONOx enables FCCU operation at low excess O 2 to achieve low NO x while maintaining low CO emissions CONOx is developed and ready for commercial implementation 6 12/13/2016

7 CONOX in Action 7 12/13/2016

8 CONOx Technology: Reactive Oxygen in Regenerator Flue Gas Duct Regenerator Off Gas Composition Flue Gas Combustion Air CONOx Oxygen Injection Boiler/HRU Regenerator Reactor Vessel Unit Type CO Excess O 2 NO x Precursors Full Burn 50 to 500 ppm 0.5 % to 3% negligible Partial Burn 1% to 8% negligible 100s ppm Riser Steam Crude Oil Gas (C 4 + lighter) Gasoline Light Gas Oil Heavy Gas Oil Fractionator Slurry Settler Clarified Slurry Conventional Oxygen Enrichment Raw Oil Charge 8 12/13/2016

9 CONOx Technology: Reactive Oxygen in Regenerator Flue Gas Duct Designed for continuous operation with minimal maintenance Hexmesh refractory coated lance (same as duct lining) 6 OD lance inserts through an 8 gate valve at optimum location for mixing as determined by CFD analysis Lance designed to be inserted through packing while unit is online Lance position and orientation optimized by CFD 9 12/13/2016

10 CFD Oxygen Mixing CONOx lance Oxygen Concentration Contours Above average, below average, and unmixed Unmixed flue gas approaches zero in about 5 duct diameters Lance mixes with entire flue gas within 5 duct diameters (7.5 m) Optimized design ensures duct is not exposed to excessively high temperatures, oxygen concentrations or velocies 10 12/13/2016

11 CO Concentration after CONOx (ppmvd) CONOx Full Burn Pilot Results Allows operation at lower excess O 2 with lower NO x leaving the regenerator Widens operational window During normal operation Regenerator startup Upset conditions Indifferent to inlet CO concentration or variations in CO concentration Outlet CO concentrations of less than 100 ppm within duct temperature limits possible Inlet Conditions Temperature = 650 to 677 C CO Concentration = ppmvd 4000 ppmvd CO 550 ppmvd CO 100 ppmvd CO Downstream Temperature ( C) Hot Oxygen offers increased flexibility to meet NO x and CO limits 11 12/13/2016

12 Case Study: Full Burn Unit Limited by Both CO and NO x Without CONOx If unit is operated with lower excess oxygen NO x decreases to below yearly permit level CO increases above yearly permit level Unit has to reduce charge rate to stay below CO permit levels Regenerator limits overall productivity With CONOx CONOx Destroys CO Flue Gas Boiler/HRU Regenerator Low excess O 2 Low NO x High CO Combustion Air 12 12/13/2016

13 NH 3 (ppmvd) DNOx (ppmvd) CONOx Partial Burn Pilot Results CONOx reduces NO x precursors NO x precursor reduction is a function of CO reduction Relatively low temperature enables conversion of precursors largely to N 2, with modest conversion to NO x With less NO x precursors in the flue gas the CO boiler will produce less NO x Stack NO x depends on total from CO boiler and CONOx Increased gas temperature going to the CO boiler CO Boiler requires less fuel gas to complete combustion Fuel gas savings will offset oxygen use to some extent CO out (%vol-dry) NH3 Model - NH3 NOx Model - NOx CONOx can address stack NO x after the CO boiler 13 12/13/2016

14 Hot Oxygen for HCN destruction HCN abatement is a concern for many industries Significant HCN destruction can be achieved with Hot Oxygen Small Hot Oxygen rate required to achieve significant reductions Lab results prove concept Model predictions : ~60-90% HCN Hot Oxygen /Flue Gas Ratio Application performance should be assessed on a case-by-case basis HCN: 5-50 ppm 1300 F Furnace Btu/hr 14 12/13/2016

15 Hot Oxygen for Pollutant Control - Summary Hot Oxygen technology has been demonstrated to significantly reduce CO, HCN and Ammonia without large increases in NO x Hot Oxygen technology can be used in combination with other pollution control technologies to offer: Improved abatement Increased throughput Operational flexibility Hot Oxygen technology can be installed on a retrofit basis with relatively low CAPEX Ideal for adapting to changing regulatory requirements Can potentially eliminate the need for costly end-of-pipe solutions (ie: SCR) Praxair has developed process modeling tools to assess anticipated performance and installation requirements for a variety of applications 15 12/13/2016

16 Other Potential Hot Oxygen Applications Debottlenecking volume limited Thermal Oxidizers Ammonia and HCN destruction from Carbon Fiber Processing Process staging for NO x control (efficient CO burnout) Other? 16 12/13/2016

17 Euan Evenson Praxair, Research and Development