CO 2 based refrigeration systems for heating and cooling. Århus 14. maj 2009 Kim G. Christensen

Transkript

1 CO 2 based refrigeration systems for heating and cooling Århus 14. maj 2009 Kim G. Christensen

2 About ADVANSOR ADVANSOR is specialized in CO 2 -technologies within the fields of refrigeration and heat pumps ADVANSOR has 8 employees and a turnover of 3 mill. euro ADVANSOR develops, manufacturers and sell projects within Combined Heating and Power Process industry Food industry Supermarkets Our products are: Heat pumps kw Chillers / AC-systems kw Supermarket refrigeration 6/15 50/250 kw Light commercial kw Costumer specified products Engineering, design, production of series of 5-10 units We work closely together with partners and suppliers and have cooperation with Danish associations, private research institutes and universities, EPA and the Ministry of Transport and Energy as well as the Danish Industry

3 Markedsmæssige træk for CO2-køleanlæg HFC giftige - lovgivning: Max 10 tørkøleropstillinger eller brændbare kg HFC pr kreds med forhøjet i praksis energiforbrug begrænsning på kw luftkølede aggregater Andre naturlige kølemidler CO 2 påtænkt at lukke hullet optil større kaskadeanlæg området mellem kw CO2-konkurrenter (transkritisk) Knudsen/ PVN (Danmark) Green and Cool (Sverige) Linde/ Carrier (Tyskland) Fischer (Tyskland) Dresdner Kühlanlagenbau (Tyskland) Costan (Italien) Enex (Italien) Blue Wave (Italien) Primære markeder Supermarkeds køl (Nordeuropa) Industriel køl/ frys (dx) Varmepumper (høje temperaturer) combine anvendelser Aircondition (chillere og dx)

4 ADVANSOR s products compheat: CHP combined heat and power Advansor develops heat pump solutions dedicated to power plants operated by either gas motor or gas turbines. The heat pump produces hot water up to 90 C which enables direct pipe connection to the external pipe work with no interference with the motor and piping. compbine: Combined heating and cooling Combined heating and cooling - produce hot water up to 100 C and get ice water for free or counter wise. Advansor s product line is highly suitable in connection with pasteurisation, CIP systems and other application in food industry where coinciding demands for heating and cooling exist. Combined heating and cooling saves both capital investment and energy cost. compfort: Chiller applications and AC systems Advansor offers highly compact air cooled chillers and AC systemsin the range from 100 to 400 kw. With natural refrigerant, no toxic risk and no flammability this is a safe and economical feasible choice. compsuper: Refrigeration applications Advansor offers refrigeration systems (compressor rack s) for supermarkets and other commercial/ industrial applications. The units work with as the only refrigerant. Main focus are placed on reliability, ease of service and low energy consumption.

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6 Characteristics of CO 2 Benefits: Environmentally friendly refrigerant (ODP = 0, GWP = 1) Smaller pipe dimensions Better efficiency of compressors Better heat transfer Safety issues: Group L1 no flammability and no toxicity No restriction regarding installation and use easy to install Temperature/ pressure: -55 -> +31 C (5.5 -> 73 bar) Heavier than air Challenges : High pressures (120 bar) Standstill pressure Use of safety valves Separation of oil and liquid from CO 2 gas Energy efficiency / price CO 2

7 Ingen [T, Transcritical versus subcritical operation Tryk God faseskifte ved varmeafgivelse pinch p] afkøling for er point optimal indbyrdes skal vigtig COP undgås uafhængige for optimal i veksleren COP CarbonDioxide Transkritisk: Subkritisk: business as usual Fordele Transition: små dimensioner materiale valg Anlægget kører i de 2 driftsformer styring anlæggets udformning T [ C] Superkritisk fluid 70 bar 60 bar 35 bar 0,0017 Overhedet gas 0,2 0,4 18,7 bar 0,6 0,8-1,60-1,40-1,20-1,00-0,80 s [kj/kg-k] 0,01 0,019 0,034

8 Fundamental concerns High pressure components stand-still pressure Leak tight system Oil management Noise and vibration Water in the system System design and choice of components Availability of components Reliability of components All systems/ components tested before going into the market heavy tests for 1 year Controllers (Danfoss, industrial PLC Simens/ Beckhoff) Energy consumption PED and approval by Notified Body Education of installers and technicians Prices that can bring the technology to the market

9 Fundamental design and considerations High pressure side/ low pressure side 120 and 40/25 bar Standstill pressure for receiver 90 bar (refrigerant stays on the system) Tightness = hermetic solutions Welded carbon steel, semihermetic compressors Conical treads, metal seal, no elastomers Advanced oil management Oil cooling Oil separator with filter (99.98 % oil separation), Oil level control Noise and vibrations Flexible hoses, vibrations shoes, supports of piping Low velocities and no sharp edges and continuous optimization System design for high reliability Integrated oil cooling, liquid separator and suction gas heat exchanger Suction gas filters, filter driers to remove water from the system System design (for low energy consumption) Optimized compressor design and optimized o gas-cooler design Adiabatic humidification of the gas-cooler, heat recovery is integrated on request Safety issues - The system is CE-marked from the manufacturer All design specifications are satisfied Mechanical: MD(98/37/EC) / PED(97/23/EC) / EN378 / EN13480 / EN13445 Electrical: LVD(06/95/EC) / EMC(89/336/EC) / EN Pressostats and safety valves

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11 Systems for supermarkets trends of development

12 compsuper Advansor A/S, W total = 44,68 U = 400 [V] I = 70,86 [A] Design of systems t 1 = 0,5052 [ C] t 2 = 117,7 [ C] t gk,ud = 32 [ C] T gk,ud2 = 32 P gk,ud = 90 [Bar] Q dt unuse = 0 uk = 0 [kw] Q c = 119,7 Q HT,komp = 78,6 COP total = 1,68 [-] t e,ht = -10 [ C] Optimal COP Fixed pressure 2xTCS373=2x12,6=25,2 m 3 /h TCS362/4 + TCS362 = 16,1 m 3 /h V HT = 35,37 [m 3 /h] λht = 0,7459 [-] P m = 35 [Bar] Calculation of the cycle ηis,ht = 0,6614 [-] t 16 = 50,19 [ C] T W HT = 41,07 [kw] I HT = 65,15 16,2 = 50 Other Q ohf = 0,01225 [kw] SCC =10,6m 3 V LT = 9,379 [m 3 /h] t 15 = -24,97 [ C] λlt = 0,8 [-] ηis,lt = 0,5 [-] t e,lt = -35 [ C] Calculation of pressure drop SCC180=2,89 SCC250=3,86 SCC300=5,3 SCC350=6,75 SCC380=8,47 W LT = 3,601 [kw] I LT = 5,711 Other t 2 = 117,7 [ C] Design of piping Evap. temp. Super heat Medium temp. t e,ht = -10 [ C] t oh,ht = 10 [K] Low temp. t e,lt = -35 [ C] t oh,lt = 10 [K] Epsilon ihx ε HT = 0,01 [-] ε LT = 0,1 [-] Capacity Q HT = 60 [kw] Q LT = 15 [kw] Compressor calculation Design of condenser Design of valves (ICMT/ ETS) Receiver size Oil management PI + BOM SolidWorks for the construction

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14 Installation og operation Turn-key project from Advansor Compressor rack Condenser Evaporators, valves and controllers Installation Connection of pipes for condenser (steel) Connection of evaporators (cupper pipes) Programming of controllers and electrical wiring Start-up Leak test, pressure test and evacuation Installation of filters and driers + filling of oil Filling of CO2 gas and filling of CO2 liquid Start-up of MT and LT

15 Service and maintanance User manual Service description Oil Filers and driers CO2 level and oil level Service of semi hermetic compressors Service of heat exchangers General procedure Pump-down to receiver Relief of gas Fulfillment of maintenance Evacuation, pressurization with CO2 and restart

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17 Energy consumption for simple single stage By Transkritisk [MWh] Subkritisk [MWh] Besparelse, transkritisk [%] Stockholm 64,1 68,0 6 København 65,5 69,1 5 Amsterdam 70,6 72,0 2 Berlin 72,9 72,9 0 Paris 76,6 74,5-3 Lyon 80,8 77,0-5 Madrid 89,1 82,2-8 Marseille 91,9 83,1-11 Barcelona 93,1 83,1-12 Rom 95,0 85,0-12 Reference: DTU, Technical University of Denmark (IPU)

18 Energy consumption (booster vs. cascade) (-20%)

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20 compsuper S 2x2 (20x10 kw) - FAKTA Energiforbrug [kwh/h] Max CO2 - trans Mid CO2 - trans Min CO2 - trans Max CO2 - kaskade Mid CO2 - kaskade Min CO2 - kaskade Max R134a Mid R134a 4 Jan Feb Mar Apr Maj Juni Juli Aug Sept Okt Nov Dec Min R134a

21 compsuper S 2x2B Kapacitet: kw (frekvensomformer) Anlægget: LxHxW = 1600x2100x780 mm Vægt: 1000 kg

22 compsuper S 2x2B til Gate Gourmet - inddækket

23 compsuper XL 4x3 (70x25 kw) Indendørsopstilling: Anlægget: LxHxW = 3350x1895x780 mm Rammer kan adskilles: Køl: LxHxW = 2450x1895x780 mm Frost: LxHxW = 2450x1895x780 mm Receiver: LxHxW = 900x1895x780 mm Vægt: 1650 kg

24 compsuper XL 4x3B - SuperBrugsen Benefits from compsuper XL Reliability Optimized oil management system Protection against excessive pressure Pressure management during electrical cut-out Documented components Energy consumption Software tools of optimization Optimized controls Selection of components Documented lowest energy consumption Optimized layout 3D design of all racks Optimized for lo production cost and low service cost

25 compsuper XL 4x3B LT capacity: 45 kw at C 3 x Bitzer HC compressors MT capacity: 80 kw at C 4 x Bitzer TC compressors MP-Receiver: 130 liter, featuring system pump down 90 bar design pressure Design pressures: 25/40/120 bar Individual compressor Oil management system saftety pressure switch Air cooled gas cooler 35 dba 10 m Optimised high pressure and sub cooling control

26 compsuper S 1x0/ 2x0 Small medium temperature applications T_e = -15->+10 C Capacities: kw Kapacitet: 40 kw (frekvensomformer) Anlægget: LxHxW = 1200x1500x780 mm Vægt: 300 kg Kapacitet: 80 kw (frekvensomformer) Anlægget: LxHxW = 2000x1500x780 mm Vægt: 450 kg

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28 Partial heat recovery from CO 2 refrigeration systems % Trykgas [C] Trykgastemperatur Andel VGV af Q_c 40% 35% 30% 25% 20% 15% 10% 5% Andel af Q_c der genvindes 0 0% COP_NH3 COP_propan COP_CO2 T_e = -10C eta_is = 0,65 T_c = 20C T_VGV = 22C

29 Partiel varmegenvinding - systemudformning 80 t vand[i] Heat recovery unit F1 Control valve and pump on water side Air cooled condenser 70 t vand;ind =25 [ C] t vand;ud =50 [ C] m dot;ref=0,3 [kg/s] P gk=65 [bar] +50C Valve for gasby-pass +25C T1 Min. temp. = 25 C Valve closes at 25 C T3 Fans High pressure valve P2 T2 Temperature - water, air, refrigerant [ C] m dot;vand=0,3 [kg/s] t gk;ind=90 [ C] t luft;ind=14 [ C] t ref;intermidiate =29,57 [ ] t luft;ud=22 [ C] m dot;luft=6 [kg/s] Heat recovery unit Intermidiate pressure receiver 20 Aircooled condenser Q luft =48,5 [kw] 50% 50% Enthaly steps [0=ref entrance/ 100 ref exit] A VGV=12,99 [m^2] UA VGV=2,598 [kw * m^2] Q vand=31,5 [kw] Høj effektivitet under VGV Kold udeluft udnyttes i kondensator til underkøling Styring/ design væsentlig for at undgå kondensering, kogning, Design væsentlig for at undgå pinch problemer

30 Køleanlæg med fuld varmegenvinding: Transkritisk varmepumpedrift 90 Temperature - water, air, refrigerant [ C] t vand[i] t vand;ind =10 [ C] m dot;ref =0,5 [kg/s] t vand;ud =60 [ C] P gk =75 [bar] m dot;vand =0,55 [kg/s]t gk;ind =110 [ C] t luft;ind =10 [ C] t ref;intermidiate =29,57 [ ] t luft;ud =15 [ C] t vgv;ud =32,15 [ ] m dot;luft =2,6 [kg/s] Aircooled condenser Q luft =14,3 [kw] Heat recovery unit Enthaly steps [0=ref entrance/ 100 ref exit] A VGV =16,68 [m^2] UA VGV =10,01 [kw * m^2] Q vand =115,5 [kw] 6 4 2

31 Driftskonditioner med partiel/fuld varmegenvinding (VGV) eksempel 100 kw køl Køleanlæg Min. kondenseringstrykstyring COP 5,9 ved Pc= 52 bar, UK3 30 kw VGV kapacitet Effektoptag 20,3 kw VGV mode 60 COP 3,8 80 bar/15oc ud af gaskøler 128 kw VGV 20C ud Effektoptag 35 kw Ekstra el-effekt: T [ C] kw til ca 100 kw varme 0,2 6,7 effektfaktor til VGV -1,8-1,6-1,4-1,2-1 -0,8-0,6 70 b ar 60 b ar 35 bar 0,0017 0,4 18,7 bar 0,6 0,8 C arbond ioxide s [kj/kg-k] 0,01 0,019 0,034 0,063 m3/kg

32 Varmegenvinding fra transkritiske CO2-anlæg t vand;ind =30 [ C] t vand;ud =50 [ C] m dot;vand =0,8 [kg/s] m dot;ref =0,5 [kg/s] P gk =22 [bar] t gk;ind =70 [ C] Higher discharge gas temp Temperature - water, air, refrigerant [ C] t luft;ind =10 [ C] t ref;intermidiate =29,57 [ ] t luft;ud =15 [ C] t vgv;ud =32,15 [ ] m dot;luft =1,364 [kg/s] COP (R404A) = 1,8 COP (R744) = 2,4 (85 bar) Pinch point R744 50% Pinch point R404A Heat recovery unit t vand[i] 50% A VGV =13,62 [m^2] UA VGV =8,174 [kw * m^2] Q vand =67,2 [kw] Aircooled condenser 0 Q luft =7,5 [kw] Enthaly steps [0=ref entrance/ 100 ref exit] 6 4 2

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34 compfort 4x54 ( kw) - chiller Indendørsopstilling: Anlægget: LxHxW = 2500x1500x1100 mm Kompakt design Vægt: 1500 kg Kondensator er placeret udendørs Oversvømmet fordamper, intern VV, oliestyring, HT-styring, tørrefilter, sugefilter, smudsfilter

35 System lay-outs for AC

36 National arena in Copenhagen AC with DX CO2 Luftkonditionering: 3xcompFORT S 8x0 Anlægstype: Gas-by-pass, DX Kapacitet: 3 x 300 kw Fordampertemperatur: 7-8ºC Lufttemperatur: 15ºC Økonomi: 20% besparelse på installationen Energibesparelse: ca. 15% sammenlignet med de bedste HFC-chillere

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38 Industrielle applikationer - Måkestad Køl og frys af frugt og grønt: 2xcompSUPER XL 6x3 Anlægstype: Booster med gas-by-pass, DX Kapacitet: 2 x 150/50 kw Fordampertemperatur: -10ºC/ -35ºC Økonomi: 20% besparelse på installationen Energibesparelse: ca. 20% Sammenlignet med HFC kaskadeanlæg

39 Måkestad

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41 Why CO 2 in heat pumps COP [-] 4,0 3,8 3,6 3,4 3,2 3,0 2,8 2,6 2,4 2,2 2, COP_NH3 COP_propan COP_CO2 Vandtemperatur ud [C] Vand_ind = 30 C T_e = 0 C eta_komp = 0,65

42 Brugsvandsvarmepumper / industrivarmepumper Brugsvandvarmepumpe Fordampning -10 o C til 20 o C Varmt vand op til o C Afkøling af kølemiddel i gaskøleren er vigtigt Optimalt tryk i gaskøleren er vigtigt Intern varmeveklser er bl.a. redskab til høj udgangstemperatur på vandsiden COP 4, b a r b a r b a r -10 0,4 1 8,7 b a r 0,6 0,8 C arbond ioxide -20-1,7-1,6-1,5-1,4-1,3-1,2-1,1-1 -0,9-0,8 T [ C] 0,2 0,0017 s [kj/kg-k] Fordampning: 0 o C, Vand ind/ud= 10 o C/ 80 o C 0,01 0,019 0,034 0,063 m3/kg

43 LMTD[i] Temperature [ C] Optimal drift af gaskøleren bar, COP bar, COP 3.4 Refrigerant Water Step (Counter flow) Step[i] T_v_ind/ ud = 40/ 80 o C, Fordampning 10 o C αi[i] Temperature [ C] LMTD[i] Refrigerant Water Step (Counter flow) Step[i] αi[i]

44 Varmepumpe Lyckeby Stärkelse (SE) 280 kw varme, vand ind/ud: 30/70 o C

45 compheat 4-IKV, layout: kw heat production

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47 Advantages with Advansor systems Safety Reliability Low cost Low running cost Safety valves and pressostats CE marked in accordance with PED High level of documentation Education during first startup Tested and documented components Optimal control and surveillance open platform (Danfoss) Protection against liquid slug and optimal oil management Pack control ensures stable suction pressure Pressure management during electrical cut-out (standstill pressure) Only CO2 as refrigerant no brine or water circuits Simple design with DX configuration Easy installation with cobber pipes and AKV-valves With CO2 there no restriction regarding installation Lowest energy consumption Heat recover (100%) Cheap refrigerant Free cooling Easy and cheap installation Easy to service low service cost