To: Dave Z who wrote (73 ) 4/8/1999 10:08:00 AM From: Bradpalm1 Read Replies (2) | Respond to of 275
I found this post from Raging Bull very relevant to OILS and the technology behind syngas production and GTL: "Syngas 101...OILS, PGS, TCC..... On the phone yesterday, Mark said he's gotten several calls and e-mails about OILS' F-T process and he's sent out some e-mail replies. He summarized his responses to several people and that led me to do a little thinking. As a result, I'm going to try to put the subject of syngas-generating "front ends" for F-T reactors into some perspective because of the new OILS info. I don't think it's magic. Basic physics and chemistry apply. For this discussion, I'm just going to talk about natural gas F-T. Syngas generators (SGs) make the syngas that goes to an F-T reactor. Natural gas (NG) is first broken down into carbon (C) and hydrogen (H) and, simultaneously, oxygen (O) is added to make a mixture of H2 and CO......and that is syngas. This process takes heat energy, NG and O. The heat can be electrical arcing or partial burning of the incoming natural gas. The O can come from air, water (steam), O2 from an oxygen plant, or a combination of these. But the end product is always syngas "soup".......a mixture of H2 and CO. There are variants. SYNM's syngas contains all the nitrogen that came in with the air and their F-T reactor has to live with that. TCC, PGS and OILS SGs can have nitrogen that needs to be separated or carried along too. But that's a different topic. Anyway, back to the soup kitchen. OILS talks about using low temperature and pressure in its electric-arc-formed-plasma SG. TCC's SG uses an electric-arc-formed-plasma but at higher temperature and pressure. PGS uses an "underoxidized burner", a totally different approach. No electric arc for heating. I'm not sure, but it might be a small scale version of what Texaco calls "partial oxidation". What's REALLY important, IMHO, is the size, complexity and energy consumption of the SGs for a given amount of syngas product. Now for an analogy. The temperature at which water boils varies with pressure. In Colorado, it boils at a lower temperatures than in Florida and you have to boil things longer to get the proper "doneness". Pressure cookers are used everywhere to hasten the cooking process. The fact that the OILS SG appears to WORK at lower temperature and pressure does not automatically mean that it's BETTER. If I'm running a ketchup plant, I don't do it in Colorado without a pressure cooker. I could, but FOR THE SAME OUTPUT, I'd have to have more and/or bigger cookpots. Everybody uses energy to make their syngas soup. Nobody knows what the best "kitchen" setup is yet. I'm sure that TCC has expended considerable effort to find the "sweet spot" on the pressure/temperature/flowrate diagrams for their plasma arc SG. OILS talks about using a "cold" plasma SG. It's a relative term. You wouldn't want to stick your hand in their plasma arc. And it may be that to process 10M cu-ft of NG per day for a 1000 bpd plant, you might need a much larger OILS SG than a TCC or PGS SG because it "cooks" the syngas slower. I'm not saying I know this for a fact, it just makes sense from a physics and chemistry standpoint. The OILS SG may have an energy advantage because the syngas leaves the SG at a lower temperature so it carries less thermal energy out of the "cooker". I don't know how this affects the downstream F-T reactor or the overall process efficiency and cost. That discussion got longer than I'd hoped for....... Another point that should be mentioned is that RNTK can process natural gas containing up to 50% carbon dioxide. So OILS doesn't have the advantage they claim in that regard. Best wishes, DoopIII"