Ice Condensation Vacuum Systems

Karl Tomas Eriksson • •

German Technology meets ASAGA World Congress on Oils and Fats and 31st Lecture series Rosario – Argentina - Oct. and Nov. 2015

Traditional Multistage Ejector System with Cooling Tower 1 Booster (stage 1) 2 Booster (stage 2) 3 Main direct contact condenser 4 Ejector (stage 3) 5 Inter condenser 6 Ejector (stage 4) 7 Seal tank 8 Cooling water pump I 9 Cooling tower 10 Cooling water pump II

Low cost system but polluted cooling water Maintenance free (no risk of pollution in the condensers) Cooling tower must be cleaned time to time Air pollution

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11 Motive steam 12 Fresh water (cooling tower) 13 Bleed (cooling tower) 14 Overflow of fatty water 15 Draining 16 Gas outlet 17 Stripping steam from deodorizer 2

Alkaline Vacuum System (Chilled Water) Low energy consumption Low amount of waste water No air pollution Save operation

1 2 3 4 5 6 7 8 9A 9B 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

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Booster (stage 1) Main direct contact condenser Ejector (stage 2) Inter condenser Liquid ring vacuum pump Fat separator (buffer tank) Circulation pump pH-control unit Plate heat exchanger (in operation) Plate heat exchanger (stand by) Brine pump Compensation vessel Coolant compressor (chiller) Cooling tower pump Cooling tower Motive steam Heating steam Stripping steam from deodorizer Condensate Circulation water Chilled water Total over flow Caustic soda (NaOH) Gas outlet Fresh water (cooling tower) Bleed (cooling tower)

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Ice Condensations Vacuum System Most efficient system for large capacities Lowest energy consumption Minimum amount of waste

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Ice condenser I Ice condenser II Melting vessel Condensate pump Ejector stage1 Ejector stage 2 Air evacuation condenser Liquid ring vacuum pump Gas separator (Liquid ring vacuum pump) Re-cooler (Liquid ring vacuum pump) Refrigerant compressor Expansion valve Priority vessel Refrigerant separator Evaporative condenser

16 17 18 19 20 21 22 23 24 25

Cooling water Motive steam Stripping steam from deodorizer Gas outlet (Liquid ring vacuum pump) Over flow (liquid ring vacuum pump) Overflow (melting vessel) Heating steam Condensate Fresh water (soft water) Bleed (evaporative condenser) 4

Operation Cycle and step sequence of the Ice Condensation System Ice Condenser I on melting Ice Condenser II on loading

SWITCH OVER Ice Condenser I on loading Ice Condenser II on loading

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Ice Condenser I on pre-cooling Ice Condenser II on loading

Ice Condenser I on loading Ice Condenser II on melting

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Example of Installation of an ICE Condensation Vacuum System Ammonia Separator

Air Evacuation Unit

ICE Condenser Block

Liquid ring Vacuum Unit

Melting Vessel

Refrigerant Compressor Footer

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Main Advantages of an Ice Condensation Vacuum System significant energy saving by high efficiency far less waste water will be produced nearly no air pollution will be produced minimum space requirement (skid mounted units) R e frgi e ran t S epa ra ot r

non barometric installation newest technology with computer controlled operation

Ice C onden se r

experience by various installation world wide since 1988 S et am Je tE ej c ot r V a cuum G roup qi u di R ni g V a cuum P um p

C onden sa et M e ltni g V e sse l P um p

R e frgi e ran t C om p re sso r

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P ro ce ss V e sse l

R e frgi e ran t C onden se r

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ICE Condenser Vertical vs. Horizontal installation

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Rising film

Rising film

Falling film

Rising film

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Typical design of a Körting ICE Condenser CROSS FLOW

Air evacuation

Melting steam

Melting steam

NH3 out

NH3 in

Process flow

Process flow

Condensate Footer

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Controlled and Uncontrolled Ice Building View into a Körting ICE Condenser during loading Controlled, constant and smooth ice building due to the right condition, cycle time and operation

View into an Condenser from our competitor during loading Uncontrolled and heavy ice building due to over loading-

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Ice Building – Loading Cycle Time Chilling capacity should be design for loading and peak conditions.

Chilling capacity

Ice Condenser

100 %

==> Avoid Vacuum fluctuation !

85 % Safety margin Insolalation losses

65 %

Loading

Koertig design for 60 minutes loading cycles (3.5 mm ice layer) 5

30

60

time (minutes)

Longer loading times (> 2 hours) is not an advantage! ==> Pressure drop and electrical power will dramatically increase !

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Driving Forces for Koerting developing Ice Condensation vacuum systems Highest possible plant availability and reliability

Minimum Energy / Utilities Consumption

• 02 high quality valves at each suction steam condenser inlet; • 02 condenser inlets – Process and Heating Steam; • Horizontal condensers • Natural flow, without pumps – ammonia and heating steam cycles; • Surface Area – 2 x 100% • Condenser pipes; – Configuration; – Fixation (no welding on process side) • Position of Air Evacuation Outlet

• • – – – •

•

•

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Optimal Heat Transfer - Ice Layer and Cycle Time Lowest possible Pressure Drop; 02 Process and Heating Steam Inlets; Cross Flow Condensers Natural flow - ammonia and heating steam cycles; Optimal Melting - Fast and energy efficient without necessity for additional pumps Optimal Motive Steam Consumption Less Cooling Water  Less Waste Water Low electrical energy consumption  Low pressure drop / thinner ice layer / shorter cycles

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Comparison of the Various Systems ALKALINE CHILLED WATER

ICE CONDENSATION

Comparison of the Various Systems

∑ Motive Steam consumption

=

235 kg/h

∑ Cooling Water consumption

=

42 m³/h

∑ Motive Steam consumption

=

678 kg/h

∑ Cooling Water consumption

=

185 m³/h

(approximate daily production 600 t)

∑ Electrical Power consumption = 165 kW

∑ Electrical Power consumption =

∑ Motive Steam consumption

=

2597 kg/h

∑ Motive Steam consumption

=

3000 kg/h

∑ Cooling Water consumption

=

425 m³/h

∑ Cooling Water consumption

=

450 m³/h

210 kW

kg/ stripping steam + 10 kg/ air + 4 kg/ FFA, 80°C Design Data:= 0,489 250 ∑ Waste Water consumption m³/h ∑ Waste Water h h consumption h= 0,935 m³/h SURFACE 1,5 mbar at inlet to the vacuum system; ALKALINE motive steam pressure 10 bar abs / saturatedCONDENNORMAL WATER SATION cooling water inlet temperature 30 °C; wet bulb temperature 21 °C

∑ Electrical Power consumption = ∑ Waste Water consumption

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40 kW

= 2,854 m³/h

∑ Electrical Power consumption = ∑ Waste Water consumption

13 kW

= 3,257 m³/h

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Comparison of the Various Systems ALKALINE CHILLED WATER

ICE CONDENSATION

∑ Motive Steam consumption

=

235 kg/h

∑ Cooling Water consumption

=

42 m³/h

∑ Motive Steam consumption

=

678 kg/h

∑ Cooling Water consumption

=

185 m³/h

∑ Electrical Power consumption = 165 kW

∑ Electrical Power consumption =

∑ Waste Water consumption

∑ Waste Water consumption

= 0,489 m³/h

= 0,935 m³/h

SURFACE CONDENSATION

ALKALINE NORMAL WATER

∑ Motive Steam consumption

=

2597 kg/h

∑ Cooling Water consumption

=

425 m³/h

∑ Electrical Power consumption = ∑ Waste Water consumption

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210 kW

40 kW

= 2,854 m³/h

∑ Motive Steam consumption

=

3000 kg/h

∑ Cooling Water consumption

=

450 m³/h

∑ Electrical Power consumption = ∑ Waste Water consumption

13 kW

= 3,257 m³/h

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Comparison of the Various Systems Design Data :

250 kg/h stripping steam + 10 kg/h air + 4 kg/h FFA, 80 °C 1,5 mbar at inlet to the vacuum system motive steam pressure 10 bar abs / saturated cooling water inlet temperature 30 °C wet bulb temperature 21 °C

Cost Comparison for 8.250 operation hours / year

ICE

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ACL (cold)

ACL (warm)

Surface condensation

Steam costs (US $/t) / year

25

51.975

138.600

535.631

618.750

Re-cooling costs for the cooling water (Cent/m³) / year

10

33.000

174.900

350.625

378.675

Electrical power cost (Cent/kW) / year

10

134.475

181.500

33.000

8.250

Effluent costs (US $/m³) / year

4

16.698

30.657

94.182

107.481

Caustic soda costs 25% (Cent/kg) / year

8

0

1.980

1.980

1.980

Operation costs / year ( in US $ )

236.148

527.637

1.015.418

Difference / year ( in US $ )

878.988

587.499

99.718

Equipment price ( in US $ )

1.000.000

410.000

360.000

Difference / year ( in US $ )

675.000

85.000

35.000

Saving after 1 year

203.988

502.499

64.718

Saving after 2 years

1.082.976

1.089.998

164.436

Saving after 3 years

1.961.964

1.677.497

264.154

1.115.136

325.000

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Koerting do Brasil Ejetores e Equipamentos de Vácuo Ltda. Rua Adib Auada 35 Bloco B - Sala 110 06710-700 Cotia – SP Tel.: +55 11 4321-2745 [email protected]

www.koerting.de