Kryogeniikan sovellusalueita 1
Puhtaan aineen tila Kemialliselta koostumukseltaan homogeeninen yhdestä alkuaineesta tai yhdisteestä koostuvat systeemit. Puhtaan aineen tila on täysin määrätty, kun ainen kaksi riippumatonta tilasuuretta tunnetaan z = f (x, y) p, v, T koordinaatisto Kryogenikassa tarkastellaan prosesseja ja systeemien käyttäytymistä tilapiirrosten avulla. 2
Puhtaan aineen PVT -käyttäytyminen p, T faasimuutokset h, s kiertoprosessit p, v kompressorit T, s kiertoprosessit ln p, h kylmäkoneistot h, T höyrykattilat 3
p, T -tilapiirros Trippelipiste a kaikki 3 faasia samanaikaisesti läsnä. Höyrynpainekäyrä a c (neste-höyry) Sulamispistekäyrä a b (kiinteä-neste) Sublimaatio a:n alapuolella (kiinteä-höyry) Kriittinen piste: neste- ja kaasumainen olomuoto yhtäaikaa voimassa T c, p c, v c 4
T, s -tilapiirros Käyttökelpoinen kiertoprosesseja laskettaessa. I II III IV V VI kiinteä neste kaasu sulaminen höyrystyminen sublimoituminen Carnot n koneen prosessi kuvautuu T, s piirroksessa suorakulmiona. Suorakulmion pinta-ala kuvaa koneesta saatavaa tehoa. 5
Properties of Cryogens Source: NIST, REFPROP CRYOGEN: Fluid with normal boiling point < 120 K Cryogen Triple point (K) Boiling point (K) Critical point (K) Krypton, Kr 115.77 119.73 209.48 Methane, CH 4 90.69 111.67 190.56 Oxygen, O 2 54.36 90.19 154.58 Argon, Ar 83.81 87.30 150.69 Fluorine, F 53.48 85.04 144.41 Carbon monoxide, CO 68.16 81.64 132.86 Air, 0.76N 2 +0.23O 2 +0.01Ar 59.75 78.9 81.7 132.4 Nitrogen, N 2 63.15 77.36 126.19 Neon, Ne 24.56 27.10 44.49 Hydrogen (normal), H 2 13.96 20.39 33.19 Hydrogen (para), H 2 13.80 20.28 32.94 Helium-4, He 4-4.230 5.195 Helium-3, He 3-3.191 3.324 6
Happi Molekyylipaino 31.99 g / mol Kaasun ominaistiheys (STP) 1.326 kg/m 3 Kaasun ominaistilavuus (STP) 0.754 m 3 /kg Kiehumispiste (1 atm) 90.2 K Jäätymispiste (1 atm) 54.4 K Kriittinen lämpötila 154.6 K Kriittinen paine 5043 kpa Kriittinen tiheys 436.1 kg/m 3 Trippelipiste 54.3 K (0.148 kpa) Höyrystymislämpö kiehumispisteessä 213 kj/kg Ominaislämpö C p (STP) 0.919 kj/kgk Ominaislämpö C v (STP) 0.658 kj/kgk Tiheys (neste) kiehumispisteessä 1141 kg/m 3 Tiheys (kaasu) kiehumispisteessä 4.483 kg/m 3 Kaasu (STP) / neste (kiehumispiste) suhde 860.5 7
Happi (Cont.) Lievästi magneettinen, O 2 pitoisuuksien testaaminen kaasuseoksista Hitsaus, metallien leikkaus, polttoprosessit, otsonin valmistus, selluntuotannossa valkaisuaineena, suojakaasupakkaus, teräksen valmistus, asetyleenin valmistus, sairaalat Upotetaan savuke 30 sekunniksi nestehappeen. Sytytetään, palaminen vie 3 sekuntia. Liekki hyvin kuuma ja kirkas. Lopputilanne. 8
Happi (Cont.) Case-sovellus: Happikaasun annostelua esimerkiksi keskosten happikaappeihin seurataan magneettisuutta mittaamalla. 9
Typpi Molekyylipaino 28.01 Kaasun ominaistiheys (STP) 1.153 kg/m 3 Kaasun ominaistilavuus (STP) 0.867 m 3 /kg Kiehumispiste (1 atm) 77.3 K Jäätymispiste (1 atm) 63.2 K Kriittinen lämpötila 126.3 K Kriittinen paine 2299 kpa Kriittinen tiheys 314.9 kg/m 3 Trippelipiste 63.1 K (12.5 kpa) Höyrystymislämpö kiehumispisteessä 199.1 kj/kg Ominaislämpö C p (STP) 1.04 kj/kgk Ominaislämpö C v (STP) 0.741 kj/kgk Tiheys (neste) kiehumispisteessä 808.5 kg/m 3 Kaasu (STP) / neste (kiehumispiste) suhde 696.5 10
Typpi (Cont.) Kemiallisesti ei-aktiivinen, räjähtämätön, myrkytön (LN 2 saattaa kondensoitua seokseksi, jossa 50% nestehappea räjähdysvaara) Ilmakehässä n. 78 % (Marsin ilmakehässä 2.6 %). Suojakaasuna (kuivaus- ja hehkutusprosessit), jäähdytysaineena (laserit, infrapunadetektorit), karkaisu (teräs), öljyteollisuus Elintarviketeollisuus! 11
Typpi (Cont.) 12
Typpi (Cont.) 13
Neon Molekyylipaino 20.18 Kaasun ominaistiheys (STP) 0.835 kg/m 3 Kaasun ominaistilavuus (STP) 1.197 m 3 /kg Kiehumispiste (1 atm) 27.1 K Kriittinen lämpötila 44.65 K Kriittinen paine 2654 kpa Kriittinen tiheys 483 kg/m Trippelipiste 24.55 K (43.4 kpa) Höyrystymislämpö kiehumispisteessä 86.3 kj/kg Ominaislämpö C p (STP) 1.05 kj/kgk Ominaislämpö C v (STP) 0.636 kj/kgk Tiheys (neste) kiehumispisteessä 1207 kg/m 3 Kaasu (STP) / neste (kiehumispiste) suhde 1445 14
Neon (Cont.) William Ramsat, Morris Travers 1898 Väritön, inertti, harvinainen jalokaasu (ilmakehässä 1.5 promillea) Valmistus: Ilman nesteytys + tislaus Hyvä jäähdytyskapasiteetti (40 x He, 3 x N 2 ) Mainosvalot, korkeajänniteindikaattorit, tyhjöputket, laserit Suprajohtavuus? 15
Vety Molekyylipaino 2.016 Kaasun ominaistiheys (STP) 0.083 kg/m 3 Kaasun ominaistilavuus (STP) 11.99 m 3 /kg Kiehumispiste (1 atm) 20.4 K Jäätymispiste (1 atm) 16.2 K Kriittinen lämpötila 33.19 K Kriittinen paine 1315 kpa Kriittinen tiheys 30.12 kg/m 3 Trippelipiste 13.95K (0.148 kpa) Höyrystymislämpö kiehumispisteessä 446 kj/kg Ominaislämpö C p (STP) 14.34kJ/kgK Ominaislämpö C v (STP) 10.12kJ/kgK Tiheys (neste) kiehumispisteessä 70.96 kg/m 3 Tiheys (kaasu) kiehumispisteessä 1.331 kg/m 3 Kaasu (STP) / neste (kiehumispiste) suhde 850.3 16
Kevyin tunnettu alkuaine Vety (Cont.) 90 % maailmankaikkeuden atomeista arvioidaan olevan vetyä Maankuoren massasta 0.76 % (13.5 % maankuoren atomeista) Vety ei ole primäärienergian muoto - höyryrefermointi - termokemiallinen (aurinko!) - sähkökemiallinen - fotolyysi - biokonversio Energiasisältö 120 MJ/kg 17
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Vedyn nesteytys Vety (Cont.) Orto- ja paravety vastakkaiset spin-kvanttiluvut James Dewar, 1898 Avaruusohjelma, 1950 Vedyn varastointi wt% Kaasu 11.3 Neste 25.9 Metallihydridi 5.5 Aktiivihiili 5.2 Zeoliitti 0.8 Lasi 6.0 Nanoputki 7.0 Fulleriini 6.0 Kemiallinen 15.1 19
Vety - sovellusalueita Kemian ja petrokemian teollisuus (voiteluöljyjen ja kerosiinin valmistus) Ammoniakin ja synteettisen metanolin valmistus Elintarviketeollisuus (ruokaöljyjen ja margariinin valmistus) Metallurgia (rautaoksidin poistaminen rautamalmista) Sähkö- ja elektroniikkateollisuus (moottorien ja generaattorien jäähdytys, tyhjiöputket, kiteen kasvatusprosessit) Mistä vetyä löytää? Vesi, paperi, ammoniakki, muste, puuvilla, sokeri, parafiini, polkupyörän rengas, puu, ruostumaton teräs, lasi, muoviset lelut, 10 K kultakoru, matto, aurinkolasit, etikka 20
Futurologinen vetytalous 21
Helium Molekyylipaino 4.00 Kaasun ominaistiheys (STP) 0.165 kg/m 3 Kaasun ominaistilavuus (STP) 6.061 m 3 /kg Kiehumispiste (1 atm) 4.22K Jäätymispiste (1 atm) Ei ole Kriittinen lämpötila 5.25 Kriittinen paine 227 kpa Kriittinen tiheys 69.64 kg/m 3 Trippelipiste Ei ole Höyrystymislämpö kiehumispisteessä 20.28 kj/kg Ominaislämpö C p (STP) 5.19 kj/kgk Ominaislämpö C v (STP) 3.121 kj/kgk Tiheys (neste) kiehumispisteessä 124.98 kg/m 3 22
Nesteheliumin lämpötilaa voidaan alentaa pumppaamalla nestetilaa: Esimerkki: Kryostaatissa olevan nesteheliumin lämpötila halutaan pitää 1.4 K:ssä. Mikä on vaadittu pumppausnopeus, kun järjestelmän lämpövuoto on 0.1 W? 23
Helium (Cont.) Isotooppi 4 He: Muuttuu kiinteäksi, kun p > 25 MPa Muuttuu supranesteeksi kun T < 2.17 K (höyrynpaineessa) Isotooppi 3 He: Kaksi erilaista supratilaa Muutoslämpötila alle 0.0025 K Kiinteän heliumin rakenne on joko heksagonaalinen tiivis pakkaus (hcp) tai tilakeskeinen kuutio (bcc) 24
Helium (Cont.) Supraneste: ei kitkaa, ei viskositettia Kvantisoidut vorteksit Supratila on kvanttimekaaninen ilmiö, virtausnopeus vorteksiviivan ympäri määrytyy vakiosta h/m Supranesteiden pyöriminen on epähomogeenista Supranesteen virtaus kiertää kvantisoituja vorteksiviivoja Suprajuoksevuus Suprajohtavuus 25
Superconductivity No resistivity! = 0 T < T c No magnetic B = 0 in sc. induction! material Meissner effect 26
Configuration of Superconducting Wires and Tapes NbTi; developed to very high level Nb 3 Sn, still potential to enhance J c Suitability for Energy Applications? Bi-2212 Bi-2223 MgB 2 27
Status of 2 G Wire Development 33 organizations developing 2 G Wire Examples of typical I c values (A/cm-width) Lengths up to about 100 m 10 m 223 A 35 m 186 A 100 m 159 A short sample 1 400 A 28
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Why Superconductivity in Power Systems Common Statements Electric utility has been operating without sc for 100 years. Why now? Is sc reliable and maintainable? Sc needs cryogenic cooling. Is it feasible in power systems? Sc is for DC. Does it perform on AC? SC is expensive. Is it economically feasible? 30
Superconductivity & Energy Applications Enabling Technology Replacing Technology Pre - commercial stage SMES Fusion LTS technology & HTS technology Current limiter Flywheel Power transmission Transformer Mainly HTS technology Electric machinery SMES LTS technology 31
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Kryogeeniset nesteet - sovellutuksia 33
Cryogenic Applications Medical Chemical Electronics $10Bs Energy Cryogenics Defense Food Entertainment Environmental Manufacturing Transportation 34
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 35
Food Freezing Year 1950 1960 1970 1980 1990 2000 2010 Food freezing with LN2 begun (1960) 36
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 37
Modern Air Separation (O 2 and N 2 ) USA oxygen and nitrogen production Air separation uses more than 0.3% of US electric power Modern air separation plant USA oxygen production.tif 100 t/d typical 400 t/d typical 400-600 t/d typical 3000 t/d largest Courtesy: Praxair Air Sep Plant @ H2 storage-mcintosh.jpg 38
Steelmaking - Basic Oxygen Process Basic Oxygen Furnace Charging of Furnace Oxygen used in most steelmaking About 60% of steel produced with BOP Introduced in 1949 in Austria Increased oxidation rate of carbon 39 Decreased nitrogen content
Oxygen and Hydrogen Rockets Year 1950 1960 1970 1980 1990 2000 2010 Sputnik I Space Shuttle Apollo 11 moon landing Saturn-V Properties: H 2 and O 2 <5% of US O 2 1.8x10 6 kg LOX 5.0x10 4 kg LH 2 RL10 66.7 kn 40
LNG Import Terminal Elba Island, Savannah, GA 41
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 42
Magnetic Resonance Imaging (MRI) 1.5 T Superconducting magnets 1 W at 4 K Non-magnetic regenerators >7000 4 K cryocoolers since 1995 Cumulative number of MRI superconducting magnets sold Tumor 43
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Magnetic Levitated Train (Maglev) Superconducting magnets Japan Railway 500 km/hr 10 cm lift LTS magnets 4 magnets/cryostat 2 cryostats/coupling 7 W at 4 K 18 km test track 45 Maglev-JR.jpg
April 18, 2003, 500 km/hr Test Run 46
CERN Large Hadron Collider (LHC) 27 km ring circumference 1232 NbTi dipole magnets Each magnet 14.2 m long 8.36 T field (1.9 K cooling) 2007 expected completion Dipole magnet 7 TEV beam paths 1 TEV = 1 flying mosquito Volume = mosquito/10 12 Photo and drawing courtesy: CERN CERN LHC ridpp-ac-uk-lhc-cern.jpg 47
Critical Magnetic Fields 1 st generation HTS wire 2 nd generation HTS wire Figure courtesy: Scanlan et al. Proc. IEEE, vol. 92 (2004) 48
HTS Superconducting Motors 5 MW Ship motor (230 rpm) Motor-hts-AmSC-5mwmotor.jpg Motor-hts-siemens_neu.jpg Use high temperature superconductors 1 & 5 MW R&D motors built 35-65 K ¼ size of conventional motors Large market DEE-54030 for ship Kryogeniikka motors 49
HTS Superconducting Motors 5 MW Drawing courtesy: American Superconductor Corporation 50
Superconducting Generators Source: AmSC Use HTS on rotor (Cooling challenge) 1 st gen. 35-65 K (BSCCO); 2 nd gen. 60-75 K (YBCO) ¼ size of conventional generators Large market for electric ship drive 51
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 52
High Speed Communications Military requirements Universal receiver (Software radio) 1 Box does 5 things Low-T c superconductors High-speed A/D 0.1 W at 4 K 5 year lifetime 53
Cooled Infrared Sensors Year 1950 1960 1970 1980 1990 2000 2010 Military tactical applications Night vision About 140,000 coolers by 2000 since 1970s 0.3 to 1.75 W at 65 80 K 54
Atmospheric Infrared Imaging Airs_cut.tif Earth Observing System (EOS) Mean Surface Air Temperature AIRS data, January 2003 AIRS Pulse Tube Cryocoolers (2) 1.2 W @ 55 K 60 W input TRW May 2002 Launch airs_surface_temp1_full Jan03.jpg 55
Infrared and X-Ray Space Telescope Missions Only 4% of universe mass seen as visible Why infrared? Cold universe Obscured regions Dust emissions Molecular spectral lines Highly redshifted universe Why X-Ray? Detect dark matter Test gravitational theory X-rays around black holes Elements in universe 56
X-Ray Space Telescopes Mission Detect dark matter Test gravitational theory X-rays around black holes Elements in universe Constellation-X Cryocooler technology TES Detectors 0.1 K ADR precooled to 6 K 57
Images courtesy E. Grossman, NIST Terahertz Imaging Calibrated passive 0.1 1.0 THz image Nb airbridge microbolometer at 4 K Calibration target Image from Qinetiq (UK) 94 GHz Passive Imager (2003) Ceramic Knife Thick collar Silhouette 58 of arm Silhouette of sleeve
Required THz Noise Temperature Images courtesy E. Grossman, NIST Add white noise to 200 mk image, to simulate higher NETD 0.5 K 1 K 2 K 5 K 59
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 60
Cryopumps (15 K) 60 K 15 K Used to produce clean vacuum Required for semiconductor processing About 20,000/yr at peak DEE-54030 of semiconductor Kryogeniikka business Cryopump01.cdr 61
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 62
Cryogenic Treatment Courtesy: W. Bryson, Cryogenics Wear rate of D2 tool steel with different austenitising temperatures From D. N. Collins and J. Dormer, Deep Cryogenic Treatment of a D2 Cold-work Tool Steel, Heat Treatment of Metals, 1997, pp71-74 63
Cryogrinding 290 million scrap tires per year are generated in the U. S. Cryogenic grinding significantly reduces energy required to produce crumb (powdered) rubber (recycling) Cryogenic grinding used DEE-54030 for Kryogeniikka powdered seasonings 64
Cryogenic Applications Preservation of biological material and food Densification (liquefaction & separation) Quantum effects (fluids and superconductivity) Low dissipation (superconductivity) High-precision metrology (atomic parameters) Action over a distance (fast response) Low thermal noise Electromagnetic Electronic Low vapor pressures (cryopumping) Property changes (permanent and temporary) Tissue ablation (cryosurgery) 65
Cryogenic Catheter and Ice Ball 66
Cryosurgery Applications and Markets Cancers Skin Cervix (precancerous) Prostate Liver Kidney Lung Brain Breast Research Abnormal Uterine Bleeding 120,000 women in U.S. each year get hysterectomies for this Recovery period is 6 weeks for hysterectomy Recovery period of 1 day for cryoablation 67 Cryoablation of uterine lining received FDA approval in 2001
Cryosurgery Applications and Markets p. 2 Cardiac Arrhythmias 2.5 million in U.S. suffer from atrial fibrillation 5 million in developed world Options include medication or rf catheter treament Cryogenic catheters have advantage of sticking to heart wall Cryogenic catheters can provide mapping prior to destruction Cryoablation does not produce blood clots like rf treatment Received FDA approval in 2004 for clinical trials 68
Cryogenic Cardiac Catheter Heart arrhythmia 2 million cases in US Currently treated with medication or rf catheter Advantages of cryogenic Sticks to tissue Thermal mapping possible Clinical trials underway For atrial fibrillation ablation, the target is the ostia of the pulmonary veins. Femoral vein access is obtained at the groin by venapuncture and the 11 Fr. transseptal balloonsheath with dilator is inserted and advanced to the right atrium. In the right atrium, the tip of the dilator is extended about 1 cm beyond the end of the balloon-sheath and pressed against the intra-atrial septum. 69 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure A Brockenbrough needle is then advanced inside the dilator/sheath and then is extended about 1 cm beyond the tip of the dilator, causing the septum to be punctured. The dilator and sheath are then advanced through the puncture site. 70 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure The needle and dilator are removed, leaving the tip of the balloon sheath in place across the septum inside the left atrium. The CryoCor Cardiac Cryoablation catheter is passed through the balloon sheath and into the left atrium. 71 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure Once inside the left atrium, the catheter tip is manipulated with its steering mechanism into one of the four pulmonary veins. The sheath is advanced over the catheter so that the deflated balloon rests just outside the ostium of the pulmonary vein. 72 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure The balloon on the sheath is then inflated and advanced until the outer rim of the ostium is engaged by the balloon and therefore automatically indexed. 73 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure The catheter is then withdrawn into the sheath such that the catheter tip extends about 0.5 cm outside the sheath. The tip of the catheter is then deflected, again using the catheter steering mechanism, so that it rests against the myocardium near the ostium of the pulmonary vein. Once the catheter tip has been positioned, the freeze duration is set and the CryoCor Cryoablation console DEE-54030 is activated, Kryogeniikka initiating refrigerant flow through 74 the catheter. Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt
CryoCor Procedure An ice ball of about 1 cm in diameter quickly forms at its tip and the tip temperature displayed on the CryoCor Cryoablation console shows a rapid fall to well below 0 C. 75 Slide courtesy of CryoCor MCALCIII-cryosurgery.ppt