ISEpreg Ion Exchange Technology in Thin Juice Softening Commercial Plant Experience

Gordon J Rossiter Rohan U Seneviratne Ronald M Scarborough

Advanced Separation Technologies (Subjdiary of Calgon Carbon Corporation) 5315 Great Oak Drive Lakeland FL 338 15

1 Introduction

Ion exchange oftening has been shown to effectively reduce lime salts in carbonated beet juices and to reduce evaporator boilouts due to calcium scale deposits Also thin juice softening avoids sedimentaion during storage and crystallization of thick juice and eliminates pre-coat fi ltration Thin juice is a good feed material for ion exchange However large volumes must be treated because of the Jow density and high flow rates and large columns lines and valves are necessary High cost of conventional ion exchange equipment has hindered the implementation of ion exchange technology for softening The economics of this process has be n improved by advantages of ISEpreg moving bed ion exchange technology lower capital cost two third reduction in resin charge and lower operating costs Advanced Separation Technologies commissioned its first ISEpreg moving beel contactor at the Appledom Sugar Factory of Pfeifer amp Langen Germany in 1997 and sllccesflllly operated during the 1997 beet campaignl Consistent product quality and it s flexibi lity to accomodate feed variation were major high points of the campaign

2 ISEpreg and CSEfgtreg Moving Bed Technology

The equipment designs that are cal led ISEpreg (Ion SEParator) and CSEpreg (Chromatographic SEParator) have evolved over the last 10 years Originally there were two distribution valves shyone upper and one lower valve which servic d an elevated carousel containing some 30 chambers of ion exchange resin The carousel and the two valves were all driven by means of a centre drive shaft keyed to both rotating val e sections and the carousel This arrangement has been discussed in previous pUblications2

As the need for more piping configurations arose we modifi ed the mechanical concept to include both valves in a single assembly where each of the old valves is now machined into a set of openings at different radii in the arne plane Schematic presentation of the ISEpreg continuous contactor installation at Pfeifer amp Langen is shown in Figure 1 This shows how the various pieces of the pr sent rSEpreg s work together The heart of the technology resides in the val ve assembly which is located above the carousel The process inputs and output as well a the interconnections are hard piped to the stationary head Typical piping connections from the columns to the rotating valve head are shown in the Figures 2 amp 3

191

Figure 1 - Pfeifer amp Langen ISEP Con tinuous Contactor Installaton

Cod -----shy -_____o_ __ -------- - --shy

TiILIII J1ce

Salpltarlc Acid

-------------shy - i I

r -----il I ~

RbullbullIaCol 1 StacuU

c bullbullbull tIc 80d euro-~-]ii~middotOH[-3========== Cod o Estncdo Tan TbleCaro

Figure 2 bull Counter Current 3middotStage Se ri es Co nfi guratio n

intmtage

CI

Contact Bed Length

Variable with passe

Co nfigu ration

Used in the

Rins e amp Scrub

Eigyu Para I~J 3-Colum 0 _CQlJ filluratLon

Feed Lin

Filed Head

Coluu bullbull

bullbullbull ~ Outlet line bullbull bull bull to nelt plS~

Ads orption

Configuration

Ma ni loldiny

Columns are mounted on a turntable or carousel and have been arranged in stacks of one two or three Stacking reduces the size of the plant s foot print Columns can range from small (0 1 shy015 m diameter) to large of 3 m diameter The number of columns is generally 20 or 30 on a carousel Other combinations have been designed The column design includes internal fluid distribution using standard industry techniques Provision is made to load and unload resin from the chambers Piping from the cells to the valve is also used for extracting samples for process analysis

192

A turntable (carousel) supports the columns and rotates around the central guide shaft The valve shaft is located on the same vertical axis Both devices turn and their positions are monitored by shaft encorders This encoder information is used by a drive control system to maintain the two rotating sections in synchronization Two other back-up sy tems are part of the overall valve carousel synchronization design

The ISEpreg and CSEpreg mechan ical assembly consists of the foll owing components

ISEpreg and CSEpreg Fluid Distributi on Valve ISEp and CSEpreg Valve Drive Columns of Adsorbent Chambers

Internal Di tribution Systems (Hub Radial or Header Lateral Distributor) Adsorbent Loading and Unloading design Accessories - sight glasses pressure gauges etc

Internal Piping Hoses fo r connecting to ISEpreg and CSEpreg Valve Piping and Fittings Sample Valves

Carousel and its support Carousel Drive Drive Control System PLC

Encoders on shafts and Signal conditioners Prox imity switches Safety shut-down swith

3 Process Description

Weak acid cation resin is used for this softening process The resin is converted pound0 the sodium fonn prior to conacting wi th the juice This is done to avoid sucrose inversion and also to keep the resin in the correct operating pH range of 5-14

The chemi try of the softeni ng process is summarized below

Softening Step

2R - Na + Ca2 +

Regeneration Step

R2 - Ca + 2H+ + SO 2R - H + Ca2 + + SO

Conversion Step

R - H + N a + + OHshy

193

The ISEpreg ion exchange system consist of distribution valve with 20 stationary20 rotating ports 20 vessels filled with weak acid cation resin and auxiliary equipment as required to control process fluids in amp out f the vessels The process flow diagram (PFD) is given in Figure 4 In ISEpreg terminology a bed volume (BY) is equal to the resin rate

Resin rate Total Resin VolumelRotation Time (rn3hr) lBV

FIGURE tf 4 - THIN middotJUICE SOFTENING (WAC PROCESS)

ORIGINAL PROCESS FLOW DIAGRAM

USPUbullbull1_

TIl ICamp sst-r

bullbull 110 (UIfSDD

aACKlrtn 2I-r

The process design for thin juice softening incorporates the following steps

bull Adsorption or Service bull Wash or Sweeten-off bull Regeneraion or Acid Strip

bull Rinse bull Backwash bull Caustic Loading

194

Adsorption or Service

Since the j uice flow rate i higher than any of the other steps in the softening process majority of the ISEpreg ports are allocated to tbe adsorption lone H ot thi n ju ice 80C filtered to less than 10 microns is pumped to tbe lSEpreg unit under flow control The total fl ow is spli t in to 12 stationary ports 3-14 in parallel in the di tribution valve The jui ce then di stributed to the rotating ports and respective res in chambers located below Juice flows through the res in beds in upflow direction up to the maximum design flow rate of 50 BVhour As the juice flows through the resin di alent cations (Ca2+ M g2+ etc ) load on the resin in exchange for monovalent Na+ ions Concurrently all the cations in juice will compete to load on the resin in exchange for H+ ions if any H+ sites are availabe However as the resi n continues to exhaust the Na+ and K+ ions are displaced from the resin by Ca2+and Mg2+ ions While Na+K+ ion exchange doesn t reduce the pH of the j uice H+ ion exchange does reduce tbe pH Tb is is controlled by tbe caustic addition in tbe preceding step Upon leaving the res in chambers the softened juice flows out through the distribution val ve to the product tank

W ash or Sweeten-off

After the res in beds have been exhausted with Ca2+JMg2+ ions resin beds move through the adsorp tion wash or sweeten-off zone In this step tbe juice is displaced from the resin using clean water Water is pumped to the stationary port 1 under flo w c ntro Two ports in series are used to accomplish this job Nonnally 10- 15 bed volumes of wash water is required for thorough sweetening-off The effectiveness of swe tening off can be monitored by checking the brix at the f inal sweeten-off port and in the strip zone effluent stream

Regeneration or Acid Strip

After the resin beds are sweeten-off they are regenerated in lb acid strip zone W eak acid cation can be regenerated very efficiently with dilute acids at almost stoichiomeric regenerant capacity to give complete conversion to the H+ fonn Dilute H2S04 acid is pumped to the sationary ports 19 amp 20 in paJallel under fl ow control Since CaS04 formed during regeneration is onJy sparingly soluble care must be taken to insure that the solubi]jty of this product is not exceeded Up flow in adsorption results in concentration of Ca2+ at the bottom portion of the resin bed Down flow regeneration tog tber with very Jow acid concentration laquo03) avoid high concentration of CaS 0 4 in the resin beds Even at thi s low acid concentrations at the resin sites CaS04 formed xceeds the solubility but remains dissolved in supersaturated condition for a short time In the ISEp reg system this window of opportunity is used to flu h out the effluent with high liquid velocities th rough the resin beds before it is precipitated

195

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

Figure 1 - Pfeifer amp Langen ISEP Con tinuous Contactor Installaton

Cod -----shy -_____o_ __ -------- - --shy

TiILIII J1ce

Salpltarlc Acid

-------------shy - i I

r -----il I ~

RbullbullIaCol 1 StacuU

c bullbullbull tIc 80d euro-~-]ii~middotOH[-3========== Cod o Estncdo Tan TbleCaro

Figure 2 bull Counter Current 3middotStage Se ri es Co nfi guratio n

intmtage

CI

Contact Bed Length

Variable with passe

Co nfigu ration

Used in the

Rins e amp Scrub

Eigyu Para I~J 3-Colum 0 _CQlJ filluratLon

Feed Lin

Filed Head

Coluu bullbull

bullbullbull ~ Outlet line bullbull bull bull to nelt plS~

Ads orption

Configuration

Ma ni loldiny

Columns are mounted on a turntable or carousel and have been arranged in stacks of one two or three Stacking reduces the size of the plant s foot print Columns can range from small (0 1 shy015 m diameter) to large of 3 m diameter The number of columns is generally 20 or 30 on a carousel Other combinations have been designed The column design includes internal fluid distribution using standard industry techniques Provision is made to load and unload resin from the chambers Piping from the cells to the valve is also used for extracting samples for process analysis

192

A turntable (carousel) supports the columns and rotates around the central guide shaft The valve shaft is located on the same vertical axis Both devices turn and their positions are monitored by shaft encorders This encoder information is used by a drive control system to maintain the two rotating sections in synchronization Two other back-up sy tems are part of the overall valve carousel synchronization design

The ISEpreg and CSEpreg mechan ical assembly consists of the foll owing components

ISEpreg and CSEpreg Fluid Distributi on Valve ISEp and CSEpreg Valve Drive Columns of Adsorbent Chambers

Internal Di tribution Systems (Hub Radial or Header Lateral Distributor) Adsorbent Loading and Unloading design Accessories - sight glasses pressure gauges etc

Internal Piping Hoses fo r connecting to ISEpreg and CSEpreg Valve Piping and Fittings Sample Valves

Carousel and its support Carousel Drive Drive Control System PLC

Encoders on shafts and Signal conditioners Prox imity switches Safety shut-down swith

3 Process Description

Weak acid cation resin is used for this softening process The resin is converted pound0 the sodium fonn prior to conacting wi th the juice This is done to avoid sucrose inversion and also to keep the resin in the correct operating pH range of 5-14

The chemi try of the softeni ng process is summarized below

Softening Step

2R - Na + Ca2 +

Regeneration Step

R2 - Ca + 2H+ + SO 2R - H + Ca2 + + SO

Conversion Step

R - H + N a + + OHshy

193

The ISEpreg ion exchange system consist of distribution valve with 20 stationary20 rotating ports 20 vessels filled with weak acid cation resin and auxiliary equipment as required to control process fluids in amp out f the vessels The process flow diagram (PFD) is given in Figure 4 In ISEpreg terminology a bed volume (BY) is equal to the resin rate

Resin rate Total Resin VolumelRotation Time (rn3hr) lBV

FIGURE tf 4 - THIN middotJUICE SOFTENING (WAC PROCESS)

ORIGINAL PROCESS FLOW DIAGRAM

USPUbullbull1_

TIl ICamp sst-r

bullbull 110 (UIfSDD

aACKlrtn 2I-r

The process design for thin juice softening incorporates the following steps

bull Adsorption or Service bull Wash or Sweeten-off bull Regeneraion or Acid Strip

bull Rinse bull Backwash bull Caustic Loading

194

Adsorption or Service

Since the j uice flow rate i higher than any of the other steps in the softening process majority of the ISEpreg ports are allocated to tbe adsorption lone H ot thi n ju ice 80C filtered to less than 10 microns is pumped to tbe lSEpreg unit under flow control The total fl ow is spli t in to 12 stationary ports 3-14 in parallel in the di tribution valve The jui ce then di stributed to the rotating ports and respective res in chambers located below Juice flows through the res in beds in upflow direction up to the maximum design flow rate of 50 BVhour As the juice flows through the resin di alent cations (Ca2+ M g2+ etc ) load on the resin in exchange for monovalent Na+ ions Concurrently all the cations in juice will compete to load on the resin in exchange for H+ ions if any H+ sites are availabe However as the resi n continues to exhaust the Na+ and K+ ions are displaced from the resin by Ca2+and Mg2+ ions While Na+K+ ion exchange doesn t reduce the pH of the j uice H+ ion exchange does reduce tbe pH Tb is is controlled by tbe caustic addition in tbe preceding step Upon leaving the res in chambers the softened juice flows out through the distribution val ve to the product tank

W ash or Sweeten-off

After the res in beds have been exhausted with Ca2+JMg2+ ions resin beds move through the adsorp tion wash or sweeten-off zone In this step tbe juice is displaced from the resin using clean water Water is pumped to the stationary port 1 under flo w c ntro Two ports in series are used to accomplish this job Nonnally 10- 15 bed volumes of wash water is required for thorough sweetening-off The effectiveness of swe tening off can be monitored by checking the brix at the f inal sweeten-off port and in the strip zone effluent stream

Regeneration or Acid Strip

After the resin beds are sweeten-off they are regenerated in lb acid strip zone W eak acid cation can be regenerated very efficiently with dilute acids at almost stoichiomeric regenerant capacity to give complete conversion to the H+ fonn Dilute H2S04 acid is pumped to the sationary ports 19 amp 20 in paJallel under fl ow control Since CaS04 formed during regeneration is onJy sparingly soluble care must be taken to insure that the solubi]jty of this product is not exceeded Up flow in adsorption results in concentration of Ca2+ at the bottom portion of the resin bed Down flow regeneration tog tber with very Jow acid concentration laquo03) avoid high concentration of CaS 0 4 in the resin beds Even at thi s low acid concentrations at the resin sites CaS04 formed xceeds the solubility but remains dissolved in supersaturated condition for a short time In the ISEp reg system this window of opportunity is used to flu h out the effluent with high liquid velocities th rough the resin beds before it is precipitated

195

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

A turntable (carousel) supports the columns and rotates around the central guide shaft The valve shaft is located on the same vertical axis Both devices turn and their positions are monitored by shaft encorders This encoder information is used by a drive control system to maintain the two rotating sections in synchronization Two other back-up sy tems are part of the overall valve carousel synchronization design

The ISEpreg and CSEpreg mechan ical assembly consists of the foll owing components

ISEpreg and CSEpreg Fluid Distributi on Valve ISEp and CSEpreg Valve Drive Columns of Adsorbent Chambers

Internal Di tribution Systems (Hub Radial or Header Lateral Distributor) Adsorbent Loading and Unloading design Accessories - sight glasses pressure gauges etc

Internal Piping Hoses fo r connecting to ISEpreg and CSEpreg Valve Piping and Fittings Sample Valves

Carousel and its support Carousel Drive Drive Control System PLC

Encoders on shafts and Signal conditioners Prox imity switches Safety shut-down swith

3 Process Description

Weak acid cation resin is used for this softening process The resin is converted pound0 the sodium fonn prior to conacting wi th the juice This is done to avoid sucrose inversion and also to keep the resin in the correct operating pH range of 5-14

The chemi try of the softeni ng process is summarized below

Softening Step

2R - Na + Ca2 +

Regeneration Step

R2 - Ca + 2H+ + SO 2R - H + Ca2 + + SO

Conversion Step

R - H + N a + + OHshy

193

The ISEpreg ion exchange system consist of distribution valve with 20 stationary20 rotating ports 20 vessels filled with weak acid cation resin and auxiliary equipment as required to control process fluids in amp out f the vessels The process flow diagram (PFD) is given in Figure 4 In ISEpreg terminology a bed volume (BY) is equal to the resin rate

Resin rate Total Resin VolumelRotation Time (rn3hr) lBV

FIGURE tf 4 - THIN middotJUICE SOFTENING (WAC PROCESS)

ORIGINAL PROCESS FLOW DIAGRAM

USPUbullbull1_

TIl ICamp sst-r

bullbull 110 (UIfSDD

aACKlrtn 2I-r

The process design for thin juice softening incorporates the following steps

bull Adsorption or Service bull Wash or Sweeten-off bull Regeneraion or Acid Strip

bull Rinse bull Backwash bull Caustic Loading

194

Adsorption or Service

Since the j uice flow rate i higher than any of the other steps in the softening process majority of the ISEpreg ports are allocated to tbe adsorption lone H ot thi n ju ice 80C filtered to less than 10 microns is pumped to tbe lSEpreg unit under flow control The total fl ow is spli t in to 12 stationary ports 3-14 in parallel in the di tribution valve The jui ce then di stributed to the rotating ports and respective res in chambers located below Juice flows through the res in beds in upflow direction up to the maximum design flow rate of 50 BVhour As the juice flows through the resin di alent cations (Ca2+ M g2+ etc ) load on the resin in exchange for monovalent Na+ ions Concurrently all the cations in juice will compete to load on the resin in exchange for H+ ions if any H+ sites are availabe However as the resi n continues to exhaust the Na+ and K+ ions are displaced from the resin by Ca2+and Mg2+ ions While Na+K+ ion exchange doesn t reduce the pH of the j uice H+ ion exchange does reduce tbe pH Tb is is controlled by tbe caustic addition in tbe preceding step Upon leaving the res in chambers the softened juice flows out through the distribution val ve to the product tank

W ash or Sweeten-off

After the res in beds have been exhausted with Ca2+JMg2+ ions resin beds move through the adsorp tion wash or sweeten-off zone In this step tbe juice is displaced from the resin using clean water Water is pumped to the stationary port 1 under flo w c ntro Two ports in series are used to accomplish this job Nonnally 10- 15 bed volumes of wash water is required for thorough sweetening-off The effectiveness of swe tening off can be monitored by checking the brix at the f inal sweeten-off port and in the strip zone effluent stream

Regeneration or Acid Strip

After the resin beds are sweeten-off they are regenerated in lb acid strip zone W eak acid cation can be regenerated very efficiently with dilute acids at almost stoichiomeric regenerant capacity to give complete conversion to the H+ fonn Dilute H2S04 acid is pumped to the sationary ports 19 amp 20 in paJallel under fl ow control Since CaS04 formed during regeneration is onJy sparingly soluble care must be taken to insure that the solubi]jty of this product is not exceeded Up flow in adsorption results in concentration of Ca2+ at the bottom portion of the resin bed Down flow regeneration tog tber with very Jow acid concentration laquo03) avoid high concentration of CaS 0 4 in the resin beds Even at thi s low acid concentrations at the resin sites CaS04 formed xceeds the solubility but remains dissolved in supersaturated condition for a short time In the ISEp reg system this window of opportunity is used to flu h out the effluent with high liquid velocities th rough the resin beds before it is precipitated

195

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

The ISEpreg ion exchange system consist of distribution valve with 20 stationary20 rotating ports 20 vessels filled with weak acid cation resin and auxiliary equipment as required to control process fluids in amp out f the vessels The process flow diagram (PFD) is given in Figure 4 In ISEpreg terminology a bed volume (BY) is equal to the resin rate

Resin rate Total Resin VolumelRotation Time (rn3hr) lBV

FIGURE tf 4 - THIN middotJUICE SOFTENING (WAC PROCESS)

ORIGINAL PROCESS FLOW DIAGRAM

USPUbullbull1_

TIl ICamp sst-r

bullbull 110 (UIfSDD

aACKlrtn 2I-r

The process design for thin juice softening incorporates the following steps

bull Adsorption or Service bull Wash or Sweeten-off bull Regeneraion or Acid Strip

bull Rinse bull Backwash bull Caustic Loading

194

Adsorption or Service

Since the j uice flow rate i higher than any of the other steps in the softening process majority of the ISEpreg ports are allocated to tbe adsorption lone H ot thi n ju ice 80C filtered to less than 10 microns is pumped to tbe lSEpreg unit under flow control The total fl ow is spli t in to 12 stationary ports 3-14 in parallel in the di tribution valve The jui ce then di stributed to the rotating ports and respective res in chambers located below Juice flows through the res in beds in upflow direction up to the maximum design flow rate of 50 BVhour As the juice flows through the resin di alent cations (Ca2+ M g2+ etc ) load on the resin in exchange for monovalent Na+ ions Concurrently all the cations in juice will compete to load on the resin in exchange for H+ ions if any H+ sites are availabe However as the resi n continues to exhaust the Na+ and K+ ions are displaced from the resin by Ca2+and Mg2+ ions While Na+K+ ion exchange doesn t reduce the pH of the j uice H+ ion exchange does reduce tbe pH Tb is is controlled by tbe caustic addition in tbe preceding step Upon leaving the res in chambers the softened juice flows out through the distribution val ve to the product tank

W ash or Sweeten-off

After the res in beds have been exhausted with Ca2+JMg2+ ions resin beds move through the adsorp tion wash or sweeten-off zone In this step tbe juice is displaced from the resin using clean water Water is pumped to the stationary port 1 under flo w c ntro Two ports in series are used to accomplish this job Nonnally 10- 15 bed volumes of wash water is required for thorough sweetening-off The effectiveness of swe tening off can be monitored by checking the brix at the f inal sweeten-off port and in the strip zone effluent stream

Regeneration or Acid Strip

After the resin beds are sweeten-off they are regenerated in lb acid strip zone W eak acid cation can be regenerated very efficiently with dilute acids at almost stoichiomeric regenerant capacity to give complete conversion to the H+ fonn Dilute H2S04 acid is pumped to the sationary ports 19 amp 20 in paJallel under fl ow control Since CaS04 formed during regeneration is onJy sparingly soluble care must be taken to insure that the solubi]jty of this product is not exceeded Up flow in adsorption results in concentration of Ca2+ at the bottom portion of the resin bed Down flow regeneration tog tber with very Jow acid concentration laquo03) avoid high concentration of CaS 0 4 in the resin beds Even at thi s low acid concentrations at the resin sites CaS04 formed xceeds the solubility but remains dissolved in supersaturated condition for a short time In the ISEp reg system this window of opportunity is used to flu h out the effluent with high liquid velocities th rough the resin beds before it is precipitated

195

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

Adsorption or Service

Since the j uice flow rate i higher than any of the other steps in the softening process majority of the ISEpreg ports are allocated to tbe adsorption lone H ot thi n ju ice 80C filtered to less than 10 microns is pumped to tbe lSEpreg unit under flow control The total fl ow is spli t in to 12 stationary ports 3-14 in parallel in the di tribution valve The jui ce then di stributed to the rotating ports and respective res in chambers located below Juice flows through the res in beds in upflow direction up to the maximum design flow rate of 50 BVhour As the juice flows through the resin di alent cations (Ca2+ M g2+ etc ) load on the resin in exchange for monovalent Na+ ions Concurrently all the cations in juice will compete to load on the resin in exchange for H+ ions if any H+ sites are availabe However as the resi n continues to exhaust the Na+ and K+ ions are displaced from the resin by Ca2+and Mg2+ ions While Na+K+ ion exchange doesn t reduce the pH of the j uice H+ ion exchange does reduce tbe pH Tb is is controlled by tbe caustic addition in tbe preceding step Upon leaving the res in chambers the softened juice flows out through the distribution val ve to the product tank

W ash or Sweeten-off

After the res in beds have been exhausted with Ca2+JMg2+ ions resin beds move through the adsorp tion wash or sweeten-off zone In this step tbe juice is displaced from the resin using clean water Water is pumped to the stationary port 1 under flo w c ntro Two ports in series are used to accomplish this job Nonnally 10- 15 bed volumes of wash water is required for thorough sweetening-off The effectiveness of swe tening off can be monitored by checking the brix at the f inal sweeten-off port and in the strip zone effluent stream

Regeneration or Acid Strip

After the resin beds are sweeten-off they are regenerated in lb acid strip zone W eak acid cation can be regenerated very efficiently with dilute acids at almost stoichiomeric regenerant capacity to give complete conversion to the H+ fonn Dilute H2S04 acid is pumped to the sationary ports 19 amp 20 in paJallel under fl ow control Since CaS04 formed during regeneration is onJy sparingly soluble care must be taken to insure that the solubi]jty of this product is not exceeded Up flow in adsorption results in concentration of Ca2+ at the bottom portion of the resin bed Down flow regeneration tog tber with very Jow acid concentration laquo03) avoid high concentration of CaS 0 4 in the resin beds Even at thi s low acid concentrations at the resin sites CaS04 formed xceeds the solubility but remains dissolved in supersaturated condition for a short time In the ISEp reg system this window of opportunity is used to flu h out the effluent with high liquid velocities th rough the resin beds before it is precipitated

195

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

Following regeneration resin beds move to the rinse zone In this step regenerant i displaced from the resin beds using clean water Water is pumped to stationary port 17 under flow control Two ports in series are used to accomplish this job The rinse effluent exiting port 18 is mixed with the regenerant and reused in the strip ports Reusing the rinse effluent achieves maximum efficiency of the regenerant chemical The effectiveness of the ri nse can be checked by sampling the effluent from the cleanest rinse port

Backwash

Backwash is done after regeneration where the resin volume in the cell is at the lowest or the free board is at the higbest Clean water is pumped to port 16 under flow control to achieve 50-75 resin bed expansion

Caustic Loading

A dlute caustic solution is used to convert the resin to the Na+ form to avoid sucrose inversion in the adsorption step Dilute Caustic (-4) is pumped to stationary port 15 under flow control in up flow direction The amount of caustic usage is controlled by the product pH A characteri tic of weak acid resins is that in going from H+ form to Na+ form resin swells significantly Approximately 75 free board is allowed in the vessels to accomodate thi expansion Also low flow rate in th is zone together with up flow allows the resin bed to expand freely and avoid high pressure drops across the resin beds

4 Commercial Plant Specifications

The main process design and equipment specifications of the commercial plant at Pfeifer amp Langen are summarised below

Process Specifications

Thin juice fl ow 350 m3lhr Feed hardness 14 degdH Softened juice hardness lt1 degdH Operating temperature 80 C Design temperature 90 C Operating pressure 50 pSI Design pressure 75 pSI Resin type Weak acid cation macroporous Resin volume 12 m3

Regenerant 03 H2S04

196

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

EquiRment Specifications

ISEpreg model TC-1536-220-20 was used in this system

Overall Height 24 f t Tum Table Diameter 15 ft Distribution valve size 20 inch Y alve material pp tationary head

Hastelloy rotating head Re in chamber diameter 36 inch Resin chamber malerial Rubber lined carbon steel Stacking 2 stacks high Carou el rotation lime 18 hrsrotation

54 minstep Speed range 4-40 hrsrotation

5 Advantages of ISEpreg Ion Excbange Technology - Commercial Plant Experience

The main advantages of ISEpreg continous ion exchange technology over fixed bed are summarised be low

bull Reduced Sorbent (Resin) Requirement bull Lower Chemical and Water Consumption bull Process Flexibility for Optimization bull Reduced Investment in Control Sy tern bull Small Plant Footprint bull Continuous Proces amp Consistent Product Quallty bull Lower Operating and Maintenance Cost bull Lower Risk for Microbiological Growth

Reduced Sorbent (Res in) Requirement

The abi li ty to process 1arge flow volumes through relatively shallow and mUltiple resin beds coupled with the advantages of the continuou proce s where the resin is in use at al l the time makes it possible to reduce the resin requirement to almost a third of fixed beds At Pfeifer amp Langen only 12 m3 of resin is used to treat 350 m3lhr of thin juice feed

Lower Chemical and Water Con umption

Reverse flow regeneration upfl ow service and downflow regeneration coupled with reuse of rinse effluent achieves complete r generation with al most 100 of toichiometric acid requirement ISEpreg technology enjoys all benefits of counter current fluidresin contact to achieve high wash and rinse efficiencies Water usage is only 10 m3lhr (15 BY) for wash (sweeten-off) and 20 m3lh r (30 BY) fo r rinse

197

Process Flexibility for Optimization

Early plant experience showed that it was difficult to flow 350 m3hr design flow through 12 ports This was due to over pressure caused by resin swelling Pressure spikes (Figure 5) du ring valve indexing exceeded the maximum design pressure and led to plant shutdowns D uring thi time by-passing of feed flow was necessary and hard ness speci fication was not quite achie ed

This situaton was corrected by the following adjustments to the ISEPreg configurati on

bull First port in adsorption was changed from up flow to down flow This helped to loosen the packed resin bed which was caused by resin expansion in the preceding conver ion step with caustic

bull Two more ports were made available for adsorption to increase the Dumber of ports from 12 to 14 This was achieved by reducing sweeten-off from 2 to 1 port and eliminating acid rinse completely Backwash port was used for dual func toD of backwash and acid nnse

bull New rinse port was added for caustic rinse

The above changes reduced the pressure drop across the adsorption zone by - 08 barg and the plant was able to operate at design feed flow capacity of 350 m hr without any interruptions The pressure spikes during indexing still occured but at a much smaller amplitude (Figure 6) The modified process flow diagram given in Figure 7 was accomplished by pipe switch ing at the stationary head connections with minimum downtime This dem onstrated the flexibili ty of the ISEpreg system for optimization

Figure 5 - Pressure Spikes Early Operation Figure 6- PressuJU[Qf~Afla r Chal19Hshy

approx 54 minibarg 11--- lprox 54 min~

barg

Irace

ISEP

Inlet 3040 ISEP Pressure

Inlet

Pressure

20 H _ bullbull _ bullbullbull _30

Splk Corrllponded to VIv lndulng

Lower vlrg lS o pprol 0 bug lower

Splku Corrnpondld to Vllvolndexlno Vlry LlrOI Splk Ihut down the ISEP SplktS tlill occur but much lIIIlllllllllpllllldt

---~ Time---~ Time

198

FIGURE 7 - THIN JUICE SOFTENING (WAC PROCESS)

MODIIIIED PROCESS PLOW DIAGRAM

ACDII 1f00 DnllKln U- _ ~

ISEpreg systems capablity to accomodate feed variations borh hardness and flowrate was another high point of the campaign Feed ionic load variations due to hardness and volume flow can be compensated by simply changing the rotation time At high ionic load situations the resin is made to work harder by reducing the rotation time This increases the resin rate or in other words the resin is presented at a faster rate to the different zones Pfeifer amp Langen design rotation time and resin rate were 18 hours and 067 mJlbr respectively At the begining of the campaign the plant was operated at 300 m3lhr by simpJy changing the cycle time to 21 hours The overall Thin Ju ice softening performance of the ISEpreg continuous contactor system during 1997 be t campaign is shown in Figure 8

199

Figure 6 - Softening Performance - 1997 Cam paign

120 ----It -I

100

f) f) ~

CII CI 80 z 40

n ---a-------------~----------------------------middot---n

bull ~ bull IPeribd = = _i - - - ~~~~_~ -~--~~~i~~ ~~~ ~-~-~-~~~~_- (+-~~_=~~ ~=~_+~j~-~+-~~~~--17-~~

= - -1 ~ -

_ _ - _- - - _- i i - - bull - - _ bull 1

80 +_---A-I+-=~-4-~~IT---I---+---+_-+_---=+_-T+_--T~-- --j-~_-I---=i

l =V II B ~-Pa sinQ

ill Con iQur ticn Changed

I -

0 0 0 0 0 N - 10 ai cO I thin juice in - thin juice out

Reduced Investment in Control System

The softening process is controlled primari ly by the valvecarousel rotation speed This along with the continuous operation of the sy tern make the control sy tern impJe and cost effective Pfeifer amp Langen ci ted this as one of the major advan tagous over fixed beds

Small Plant Footprint

The ISEpregsystem size is primarily determined by the turntable diameter Abi]jty to stack resin chambers on the turntable and the non-requirement of interstage tanks provide ISEpregtechnology an added advantage over f ixed beds The Pfeifer amp Langen system foot print is 15 ft di ameter

Continuous Process amp Consisten t Products Quality

Continuous process make it possible to independently control different feed streams simultaneously to obtain stringent product requirements Consistent product quality was a major high point of the Pfeifer amp Langen beet campaign

200

Lower Operati ng and Maintenance Costs

The ISEpreg system typically require very low level of mechanical adjustments during operation and the maintenance costs are very low Operator time required is only for collecting samples and maintaining peripheral equipmen t Operating cost savings are given in Table 1 It shoul d be noted that labor and maintenance cost savings wh ich are considered significant are not included in the table due to unavai lability

Table 1 - Operating~--~--~O

Savingsyear

Soda 299 199 100 tonnes

Acid 280 234 46 tonnes

Power 235 190 45 Mwh

Resin 4 (4) rd Boil-out 15K OM

Filter-aid 16 16 tonnes

Anti-scale 75 75 tonnes

Based on estimated resin life of 3 years

Lower Risk fo r Microbiological Growth

Continuous process and fas t tum -over of process liquids in the ISEpreg system reduced the risk of microbiological growth normal1y assoc iated with fi xed beds treating low brix sugar solutions At Pfeifer amp Langen 1997 beet sugar campaign was completely free of microbiological growth problems

201

6 References

1 G Klohn amp M Bukhardt Pfeifer amp Langen Appledom Germany Thin Juice Softening According to the Tasco Process with a Continuous Ion Exchange Plant of the ISEpreg System Paper~presented to the German Beet Sugar Research Institute April 1998

2 G J Rossiter Advanced Separation Technologies Inc Lakeland Florida A Division of Calgon Carbon Corporation ISEpreg and CSEPreg A Novel Separation Technique for Process Engineers Paper presented to the Israeli Mining Institution December 1996

7 Acknowledgments

We would like to thank Herr Klohn amp Herr Bukhardt of Pfeifer amp Langen for permission to use their data on the ISEPreg continuous ion exchange plant

202

-------------~----- -

FIGURE 7 - THIN JUICE SOFTENING (WAC PROCESS)

MODIIIIED PROCESS PLOW DIAGRAM

ACDII 1f00 DnllKln U- _ ~

ISEpreg systems capablity to accomodate feed variations borh hardness and flowrate was another high point of the campaign Feed ionic load variations due to hardness and volume flow can be compensated by simply changing the rotation time At high ionic load situations the resin is made to work harder by reducing the rotation time This increases the resin rate or in other words the resin is presented at a faster rate to the different zones Pfeifer amp Langen design rotation time and resin rate were 18 hours and 067 mJlbr respectively At the begining of the campaign the plant was operated at 300 m3lhr by simpJy changing the cycle time to 21 hours The overall Thin Ju ice softening performance of the ISEpreg continuous contactor system during 1997 be t campaign is shown in Figure 8

199

Figure 6 - Softening Performance - 1997 Cam paign

120 ----It -I

100

f) f) ~

CII CI 80 z 40

n ---a-------------~----------------------------middot---n

bull ~ bull IPeribd = = _i - - - ~~~~_~ -~--~~~i~~ ~~~ ~-~-~-~~~~_- (+-~~_=~~ ~=~_+~j~-~+-~~~~--17-~~

= - -1 ~ -

_ _ - _- - - _- i i - - bull - - _ bull 1

80 +_---A-I+-=~-4-~~IT---I---+---+_-+_---=+_-T+_--T~-- --j-~_-I---=i

l =V II B ~-Pa sinQ

ill Con iQur ticn Changed

I -

0 0 0 0 0 N - 10 ai cO I thin juice in - thin juice out

Reduced Investment in Control System

The softening process is controlled primari ly by the valvecarousel rotation speed This along with the continuous operation of the sy tern make the control sy tern impJe and cost effective Pfeifer amp Langen ci ted this as one of the major advan tagous over fixed beds

Small Plant Footprint

The ISEpregsystem size is primarily determined by the turntable diameter Abi]jty to stack resin chambers on the turntable and the non-requirement of interstage tanks provide ISEpregtechnology an added advantage over f ixed beds The Pfeifer amp Langen system foot print is 15 ft di ameter

Continuous Process amp Consisten t Products Quality

Continuous process make it possible to independently control different feed streams simultaneously to obtain stringent product requirements Consistent product quality was a major high point of the Pfeifer amp Langen beet campaign

200

Lower Operati ng and Maintenance Costs

The ISEpreg system typically require very low level of mechanical adjustments during operation and the maintenance costs are very low Operator time required is only for collecting samples and maintaining peripheral equipmen t Operating cost savings are given in Table 1 It shoul d be noted that labor and maintenance cost savings wh ich are considered significant are not included in the table due to unavai lability

Table 1 - Operating~--~--~O

Savingsyear

Soda 299 199 100 tonnes

Acid 280 234 46 tonnes

Power 235 190 45 Mwh

Resin 4 (4) rd Boil-out 15K OM

Filter-aid 16 16 tonnes

Anti-scale 75 75 tonnes

Based on estimated resin life of 3 years

Lower Risk fo r Microbiological Growth

Continuous process and fas t tum -over of process liquids in the ISEpreg system reduced the risk of microbiological growth normal1y assoc iated with fi xed beds treating low brix sugar solutions At Pfeifer amp Langen 1997 beet sugar campaign was completely free of microbiological growth problems

201

6 References

1 G Klohn amp M Bukhardt Pfeifer amp Langen Appledom Germany Thin Juice Softening According to the Tasco Process with a Continuous Ion Exchange Plant of the ISEpreg System Paper~presented to the German Beet Sugar Research Institute April 1998

2 G J Rossiter Advanced Separation Technologies Inc Lakeland Florida A Division of Calgon Carbon Corporation ISEpreg and CSEPreg A Novel Separation Technique for Process Engineers Paper presented to the Israeli Mining Institution December 1996

7 Acknowledgments

We would like to thank Herr Klohn amp Herr Bukhardt of Pfeifer amp Langen for permission to use their data on the ISEPreg continuous ion exchange plant

202

-------------~----- -

Figure 6 - Softening Performance - 1997 Cam paign

120 ----It -I

100

f) f) ~

CII CI 80 z 40

n ---a-------------~----------------------------middot---n

bull ~ bull IPeribd = = _i - - - ~~~~_~ -~--~~~i~~ ~~~ ~-~-~-~~~~_- (+-~~_=~~ ~=~_+~j~-~+-~~~~--17-~~

= - -1 ~ -

_ _ - _- - - _- i i - - bull - - _ bull 1

80 +_---A-I+-=~-4-~~IT---I---+---+_-+_---=+_-T+_--T~-- --j-~_-I---=i

l =V II B ~-Pa sinQ

ill Con iQur ticn Changed

I -

0 0 0 0 0 N - 10 ai cO I thin juice in - thin juice out

Reduced Investment in Control System

The softening process is controlled primari ly by the valvecarousel rotation speed This along with the continuous operation of the sy tern make the control sy tern impJe and cost effective Pfeifer amp Langen ci ted this as one of the major advan tagous over fixed beds

Small Plant Footprint

The ISEpregsystem size is primarily determined by the turntable diameter Abi]jty to stack resin chambers on the turntable and the non-requirement of interstage tanks provide ISEpregtechnology an added advantage over f ixed beds The Pfeifer amp Langen system foot print is 15 ft di ameter

Continuous Process amp Consisten t Products Quality

Continuous process make it possible to independently control different feed streams simultaneously to obtain stringent product requirements Consistent product quality was a major high point of the Pfeifer amp Langen beet campaign

200

Lower Operati ng and Maintenance Costs

The ISEpreg system typically require very low level of mechanical adjustments during operation and the maintenance costs are very low Operator time required is only for collecting samples and maintaining peripheral equipmen t Operating cost savings are given in Table 1 It shoul d be noted that labor and maintenance cost savings wh ich are considered significant are not included in the table due to unavai lability

Table 1 - Operating~--~--~O

Savingsyear

Soda 299 199 100 tonnes

Acid 280 234 46 tonnes

Power 235 190 45 Mwh

Resin 4 (4) rd Boil-out 15K OM

Filter-aid 16 16 tonnes

Anti-scale 75 75 tonnes

Based on estimated resin life of 3 years

Lower Risk fo r Microbiological Growth

Continuous process and fas t tum -over of process liquids in the ISEpreg system reduced the risk of microbiological growth normal1y assoc iated with fi xed beds treating low brix sugar solutions At Pfeifer amp Langen 1997 beet sugar campaign was completely free of microbiological growth problems

201

6 References

1 G Klohn amp M Bukhardt Pfeifer amp Langen Appledom Germany Thin Juice Softening According to the Tasco Process with a Continuous Ion Exchange Plant of the ISEpreg System Paper~presented to the German Beet Sugar Research Institute April 1998

2 G J Rossiter Advanced Separation Technologies Inc Lakeland Florida A Division of Calgon Carbon Corporation ISEpreg and CSEPreg A Novel Separation Technique for Process Engineers Paper presented to the Israeli Mining Institution December 1996

7 Acknowledgments

We would like to thank Herr Klohn amp Herr Bukhardt of Pfeifer amp Langen for permission to use their data on the ISEPreg continuous ion exchange plant

202

-------------~----- -

Lower Operati ng and Maintenance Costs

The ISEpreg system typically require very low level of mechanical adjustments during operation and the maintenance costs are very low Operator time required is only for collecting samples and maintaining peripheral equipmen t Operating cost savings are given in Table 1 It shoul d be noted that labor and maintenance cost savings wh ich are considered significant are not included in the table due to unavai lability

Table 1 - Operating~--~--~O

Savingsyear

Soda 299 199 100 tonnes

Acid 280 234 46 tonnes

Power 235 190 45 Mwh

Resin 4 (4) rd Boil-out 15K OM

Filter-aid 16 16 tonnes

Anti-scale 75 75 tonnes

Based on estimated resin life of 3 years

Lower Risk fo r Microbiological Growth

Continuous process and fas t tum -over of process liquids in the ISEpreg system reduced the risk of microbiological growth normal1y assoc iated with fi xed beds treating low brix sugar solutions At Pfeifer amp Langen 1997 beet sugar campaign was completely free of microbiological growth problems

201

6 References

1 G Klohn amp M Bukhardt Pfeifer amp Langen Appledom Germany Thin Juice Softening According to the Tasco Process with a Continuous Ion Exchange Plant of the ISEpreg System Paper~presented to the German Beet Sugar Research Institute April 1998

2 G J Rossiter Advanced Separation Technologies Inc Lakeland Florida A Division of Calgon Carbon Corporation ISEpreg and CSEPreg A Novel Separation Technique for Process Engineers Paper presented to the Israeli Mining Institution December 1996

7 Acknowledgments

We would like to thank Herr Klohn amp Herr Bukhardt of Pfeifer amp Langen for permission to use their data on the ISEPreg continuous ion exchange plant

202

-------------~----- -

6 References

1 G Klohn amp M Bukhardt Pfeifer amp Langen Appledom Germany Thin Juice Softening According to the Tasco Process with a Continuous Ion Exchange Plant of the ISEpreg System Paper~presented to the German Beet Sugar Research Institute April 1998

2 G J Rossiter Advanced Separation Technologies Inc Lakeland Florida A Division of Calgon Carbon Corporation ISEpreg and CSEPreg A Novel Separation Technique for Process Engineers Paper presented to the Israeli Mining Institution December 1996

7 Acknowledgments

We would like to thank Herr Klohn amp Herr Bukhardt of Pfeifer amp Langen for permission to use their data on the ISEPreg continuous ion exchange plant

202

-------------~----- -