TEKNOLOGIST INSTITUT Århus Oktober Arne Sloth Jensen. Tørring af roepulp og andre produkter I overhedet damp. EnerDry ApS

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1 TEKNOLOGIST INSTITUT Århus Oktober 2008 Arne Sloth Jensen Tørring af roepulp og andre produkter I overhedet damp.

2 1. Udvikling af damptørringsteknikken. 2. Hvordan virker tørreren. 3. Kapaciteter 3. Næsten 100% energibesparelse 4. Pulp som brændstof 5. Miljø 6. Forøget produktion 7. Udviklingen i USA. 8. Damptørring i Europa. 9. Økonomi 10. Tørring af andre produkter. 11. Energibesparelse og reduktion af CO 2 emission. 12. Konklusion.

3 EnerDry EnerDry ApS ApS

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5 Wet pulp Heat 3,5 bar Steam Dry pulp

6 Udvikling af damptørringsteknologien 1979 De første ideer 1981 Oliekrise, Start af udviklingsarbejdet Pilotanlæg 1985 Prototype i Stege, 1990 Secheur installé en Nangis, France anlæg i drift + 1 under bygning.

7 Steam from top also possible. Window Box 6'' x 6'' for up to 5 bar Cell for drying small samples in steam. Superheated steam EnerDry EnerDry ApS ApS

8 Product in Pressure control Flow control Electric superheater Boiler 5 bar Product out EnerDry EnerDry ApS ApS

9 Installation pilot en construction 1983

10 l Installation pilot 1983

11 L Installation pilot de debut.

12 L Installation pilot modifiée

13 Prototype 1985

14 Prototype

15 Le sécheur. Sucrerie de Nangis

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30 Steam in and out Boiler steam (400 psig) lb/h Steam to evaporator Pure flash steam to evap. Returned total lb/h lb/h lb/h

31 Energy supplied Supplied heat Steam for heating (53119 kw -318 kw) Condensate out 34722kWh lb = kw kw kw 1076 Btu lb evap. = 2501 kj/(kg evap) Supplied power 1220 kw Which is roughly the double of a drum dryer with same capacity

32 Energy consumption Supplied and used energy 1400 Btu/lb evap Supplied energy 1076 Btu/lb evap Btu/lb evap Returned energy Drum Dryer Steam Dryer Used energy 19 Btu/lb evap

33 Indpasning i eksisterende sukkerfabrik. Aldrig ændringer I kedelhuset. El-produktionen bliver ofte ændret. Det første trin i fordampeapparatet må være delt i 2 parallelle trin.

34 1 Loss 20.4 Turbine Boiler 28 barg 300ºC Evaporators Total Energy flow in a factory with drum drying of pulp ton beets / day MW energy flow 45.2 Pulp 3.4 Drum Dryer Pulp 1 21 t/h 0.6 Loss 18.5

35 2 Loss 19.2 Turbine 6 8 Boiler barg 300ºF Evaporators Total 93.6 Loss Energy flow in a factory with steam drying of pulp ton beets / day MW energy flow Pulp 3.4 Steam Dryer Pulp 1 23 t/h

36 Hvordan kan brændstofforbruget i kedelhuset blive reduceret. El-produktionen er reduceret.. Strømforbruget til tørreren genvindes. Energien i den 50 o C varme pulp bliver løftet op til niveauet for damp til fordampeapparatet.

37 Beet pulp as fuel The power production is based on: t beets per day. All pulp is burned in the boiler. Boilers produce 85 bar steam at 525 C. Boiler efficiency 88% Isentropic efficiency of turbine 85% Efficiency of gear and generator 95% The condenser temp is as high as 60 C. Lower condenser temperature could increase the power production.

38 Evironmental improvements. Tørringen finder sted I et lukket system. Derfor er der ingen emmission til atmosfæren.. * Intet Støv * Ingen VOC (lugt) * Ingen CO 2

39 Intet støv til atmosfæren. Men dampen fra tørreren har 2ppm små partikler, som ender som suspended stof i kondensatet.

40 Ingen VOC (ingen Volatile Organic Components). Ingen lugt. Det er et lukket system, men der er nogle ikke kondenserbare gasser. Denne udluftning indeholder nogle organiske syrer og andre VOC. Varmen i denne skal udnyttes, hvorved disse stoffer går over i vandfasen. (kondensatet) Den resterende emission kan på denne måde bringes ned under 25 gc/h fra 50 t/h vandfordampning.

41 Vandfasen forøger BOD belastningen på sukkerfabrikken spildevand med ca. 2%

42 Tabt produktion fra forbrænding.

43 Steam dried beet pulp vs. Drum dried beet pulp

44 Loss of product by burning in drumdriers.

45 Steamdryers in USA Compagny State Dryer Supplier Nominel capacity Used capacity MN 2 x size 10 Niro x 40 t/h 2 x 40 t/h SMBCS Rebuildt by EnerDry 2004 Minn-Dak ND Size H EnerDry t/h 40 t/h Farmers Amalgamated ID Size J EnerDry t/h 73 t/h Nampa Michigan MI Size H EnerDry t/h 38 t/h Bay City American Crystal Sugar MN Size H EnerDry t/h East Grand Forks

46 Piping around steam dryer Nampa

47 Steamsystem at Nampa sugar factory Steam System Nampa

48 Steam supply Pulp in Pulp out Evap Guarantee 14/28 bar 67t/h Guarantee 28/28 bar 71 t/h Avarage 24h 14 Febr Calculated max Capacity* 13,5/24,8 bar 14/28 bar 100 t/h 114 t/h 27 t/h 31 t/h 73 t/h 83 t/h *Calculated based on operation data. Not tested due to steam system and lack of pulp

49 Steam dryer reduces potential for power production. Split 200/400 super heater gives less power reduction 2006/07 Reduced power production 4 MW 2007/08 Future reduced power production 2.5 MW Saved fuel 62.0 MW The saved fuel could make 30 MW power in a modern power plant.

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57 Pulp Dryer Stacks Before Steam Drying Operation

58 Pulp Dryer Stacks After Steam Dryer Operation

59 Steamdryer at Bay City, Michigan

60 The steamdryer at Minn-Dak Farmers, North Dakota

61 Damptørring af roepulp i Europe. Der er 10 damptørrere I drift I Europa for tiden. Heraf 6 i i Østtyskland, hvor alt det pulp der tørres, bliver tørret i overhedet damp under tryk. De to ældste står i Frankrig. De blev sat i drift i 1990 og De fleste øvrige blev bygget i 90 erne

62 Ny interesse for damptørring i Europa 1) Stor stigning i energipriserne. 2) Krav om reduceret støvemmision. 3) Reduktion af CO 2 emission. 4) Kommende krav om reduceret lugt og reduceret VOC emission. 5) Efter at EU sukkerordningen er faldet på plads begynder investeringerne så småt igen.

63 Energibehov i dag. I Vesteuropa har der været en god udvikling i energibehovet over de sidste 30 år fra ca 250 kwh/tom roer til 170kWh/t roer i selve fabrikken. I dag 170 kwh/ton beet. Tromletørring af pulp 90 kwh/ton beet. Total 260 kwh/ton beet. Der findes en fabrik der damptørrer 75% af pulpen og laver al den strøm som fabrikken har behov for. Den bruger kun 157 kwh/t pr ton roer. (Målt gennemsnit for en uge).

64 Economy Minn-Dak Farmers. Max 50 t/h evaporation 2003; 9.3 mill $ = 6 mill. for the total project Amalgamated Sugar Co. Nampa Factory. 2006; Max 83 t/h evaporation. 16,5 mill $=10,6 mill for the total product.

65 Economy In Europe a 50 t/h (Size H) project could cost like this: Investment: Dryer ex works 4,3 mill Transport and erection 1.2 mill Evaporator 1,0 mill Building 1,2 mill Piping and conveyors 1,8 mill Varoious 1,0 mill Total 10,5 mill

66 Economy Yearly profit from steamdrying. Gain per year. Saving on gas: 45000x3000/3600/1000=37,5 MW 37,5x29x24x100= 2,61 mill No pulp burnt 1,5x100x24 180= 0,65 mill Saving on labor and Maintenance. 0,20 mill Total 3,46 mill Lost power production -0,25 mill Net gain per 3,21 mill 100 day campaign The numbers are based on: Assumed 45t/h evaporation out of max 50 t/h Gas: 29 /MWh Losses in the alternative drum 6% = 1,5 t/h pellets. 180 /ton pellets. Reduced power production 3 MW; 70 per MWh.

67 Why dry wet Solid Fuels? Burning wet fuel use primary energy to evaporate H 2 O The water vapor takes up volume in boiler and the exhaust gas cleaning system, reducing the capacity. Wet fuel give more pollution

68 Wood chips for district heating With steam drying and power production Power produced: 34,5 MWe District heat: 117,4 MW

69 Steamdrying of other products. 2 steamdryers for wood chips and bark in Sweden.

70 Våde brændsler, som bør damptørres. Træflis Bark Bagasse Brunkul

71 Tørret slam fra aerob vandrensningsanlæg

72 Damptørring og Ethanol Ethanol fremstilling i USA på basis af især majs er vokset voldsomt de sidste år. Det er et par hundrede fabrikker. Restproduktet tørres i tromler til DDGS. One dryer in USA has been tested for drying of DDGS from ethanol production. And a lot of lab tests has been made. By steamdrying the fuel consumption can be reduced 9200 to 5300 kj per liter ethanol. En anden slags ethanol er ølbrygning. Masken vil også være et velegnet produkt for damptørring.

73 Lucernetørring. Tidligere var tromletørring af lucerne meget udbredt, da olieprisen var lav. Damptørring af lucerne er også muligt med stor energibesparelse til følge. Der kræves en vis præparation af lucernen, hvis den er meget våd. Her et par eksempler på systemer.

74 50,4 t/h, 3,0 bar, 145 C, 2750 kj/kg, kw 67,5 t/h Boiler feed water 134 C kw AIR Boiler Size J 40 t/h evap. Alfalfa 20% DS 116 t/h Gas fired 43 bar Max 90 t/h 50 t/h evap. 30 C 126 kj/kg 1764 kw Predied Alfalfa 30,5 % DS, 76 t/h kw 1,11 MWh/ton evap. 959 kcal/kg evap kw Dryed Alfalfa 90 % DS 25,8 t/h Energy from boiler house kw 0,48 MWh/ton evaporated 415 kcal/kg evaporated.

75 71 t/h Heat from Vacuum pan vapour 71,1 t/h kw AIR Boilerhouse Gas fired 43 bar kg/h kw kg/h kw kg/h 28 bar, 250 C 2865 kj/kg kw kg/h 4625 kw 70,7 t/h evap. Size J Pulp feed 28% DS 102,6 t/h 19.3 t/h evap kw 1,5 MWh/ton evap kcal/kg evap. Pulp 28% DS 28 t/h Dried pulp 31,9 t/h 90%DS Dried pulp 8,7 t/h 90%DS Gas consumption in boiler house does not increase compared to the factory operation today. The vapour from the panboiling is free. Therefore is the heat consumption: 0 MWh/ton evaporated = 0 kcal/kg evaporated. Dried pulp 40,6 t/h 90%DS The power production will be reduced. A rough estimate of this reduction is: 9 MW if the steam compression is maintained. 3 MW if the evaporation is modified to 6 steps. Further more will the two driers consume more power than the old installation.

76 Boiler 1 Gas fired 43 bar Max 90 t/h Boiler 2 Gas fired 43 bar Max 90 t/h 91 t/h 74 t/h 73 t/h 9 t/h 100 t/h 4,6 MW 19 bar a 0 t/h 13 t/h 0 t/h 43 t/h 2 size H 3,7 bar a 80 t/h 36 t/h 5,4 MW 23 t/h 0 t/h 0 t/h 0 New 4000 m t/h 80 t/h 1 A+ B+ C size H driers. 2 x 40 t/h evap. Steamdrying and partly 5½ step evaporator. 10 MW powerprod. Low condenser loss t/h to condens er 91 t/h Boiler feed water 50 bar, 208 C Directly into boiler

77 Nampa Steam dryer 200 ton coal per day not fired. 600 t/day CO 2 emission avoided. In 120 days per year t CO 2 reduction per year No raw material used Investment: 10.6 mill 6792 t CO 2 reduction per year per invested mill

78 Nampa Steam dryer 200 ton coal per day not fired. 600 t/day CO 2 emission avoided. In 120 days per year An ethanol factory on wheat Production 8000 hl/day. Avoided CO 2 emission 1200 t/day CO 2 from cultivation: -250 t/day CO 2 from boilers: -600 t/day Net CO 2 reduction: 350 t/day In 340 days a year t CO 2 reduction per year No raw material used Investment: 10.6 mill 6792 t CO 2 reduction per year per invested mill t CO 2 reduction per year 2200 ton/day wheat is used. 700 ton/day DDGS produced Investment: 200 mill 595 t CO 2 reduction per year per invested mill

79 Nampa Steam dryer 200 ton coal per day not fired. 600 t/day CO 2 emission avoided. In 120 days per year t CO 2 reduction per year An ethanol factory on wheat Production 8000 hl/day. Avoided CO 2 emission 1200 t/day CO 2 from cultivation: -250 t/day CO 2 from boilers: -600 t/day Net CO 2 reduction: 350 t/day In 340 days a year t CO 2 reduction per year 4 x 2 MW windmills Average production: 23% = 1,8 MW. A coal fired power plant will need 3,8 MW as fuel corresponding to 500 kg coal per hour. Avoided CO 2 : 36 t/day. In 365 days a year t CO 2 reduction per year No raw material used Investment: 10.6 mill 2200 ton/day wheat is used. 700 ton/day DDGS produced Investment: 200 mill No raw material used Investment: 12 mill 6792 t CO 2 reduction per year per invested mill 595 t CO 2 reduction per year per invested mill 1083 t CO 2 reduction per year per invested mill

80 Conclusion Up to 83 ton/h water evaporation in one drier. 6 large steam dryers in operation in USA. 100% saving of fuel for drum drying is theoretical possible. Zero emission of dust, VOC or smell. More reduction of CO 2 emission then by other investments.