Energy Efficient Jaggery Making Using Freeze Pre-Concentration of Sugarcane Juice

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Energy Procedia 90 ( 2016 ) 370 – 381

5th International Conference on Advances in Energy Research, ICAER 2015, 15-17 December 2015, Mumbai, India Energy Efficient Jaggery Making using Freeze Pre-Concentration of Sugarcane Juice

Milind V Ranea, *, Dinesh B Uphadea

aHeat Pump Laboratory, Mechanical Engineering Department, IIT Bombay, Powai, Mumbai 400 076 INDIA

Abstract

Conventional jaggery making with a pan furnace consumes all bagasse for evaporation of water. Hot spots during boiling of juice causes caramelization of sugar. It gives dark brown colour to jaggery, which has low market value. Chemicals like lime, phosphoric acid and hydros powder are used as clarificant to enhance colour of jaggery. Traces of these chemicals in jaggery are harmful to human health. Freeze pre-concentration of sugarcane juice from 20°Brix to 40°Brix using a reversible heat pump saves bagasse during initial 63% water removal. Water is removed in the form of ice. It requires 335 kJ/kg heat removal, which is equivalent to 15% of heat addition during evaporation. Recycling of saved bagasse in field improves the yield of sugarcane. Juice is exposed to -5°C during pre-concentration. It reduces inversion of sucrose and expected to improve the quality of jaggery by reduced exposure time to high temperature. Simple cycle analysis for FPCS of juice shows that COPc is 18 with R22 as refrigerant at -8°C evaporator and 3°C condenser temperature. Overall system COPc is expected, to be in the range of 9 to 12 after accounting for losses like cycling of thermal mass and heat gain from ambient. Power required for 1.5 TR FPCS is 0.5 to 0.6 kWe, which is about 0.1 INR/kg of jaggery produced. Payback period for FPCS is one year. Sugar inclusion in ice is estimated using empirical correlations for flow of solution over flat surface and it is 19.1°Brix. Energy consumption, sugar loss and cost of system are estimated. Ways of reducing sugar loss are investigated along with repercussion on energy consumption and system cost. Further experimental investigations on sugar inclusion in ice, which forms inside the tube needs to be experimentally tested. © 2016 TheThe Authors. Authors. Published Published by byElsevier Elsevier Ltd. Ltd.This is an open access article under the CC BY-NC-ND license Peer-review(http://creativecommons.org/licenses/by-nc-nd/4.0/ under responsibility of the organizing). committee of ICAER 2015. Peer-review under responsibility of the organizing committee of ICAER 2015 Keywords: Freeze pre-concentration system; Reversible heat pump; COP; Bagasse saving; Sugar inclusion

* Corresponding author. Tel: +91 22 2576 7514; Fax: +91 22 2576 6875. E-mail address: [email protected]

1876-6102 © 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the organizing committee of ICAER 2015 doi: 10.1016/j.egypro.2016.11.204 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381 371

Nomenclature Greek Symbols

3 ADC average distribution coefficient, unitless ρ density, kg/m o c concentration, Brix η efficiency, % cp specific heat at constant pressure, kJ/kg.K d diameter, m h enthalpy, kJ/kg IGR ice growth rate, micron/s Abbreviations mf mass flow rate, kg/s CJ_HE Concentrated Juice Heat Exchanger p pressure, bar COP Coefficient of Performance Q heat duty, kW EV Expansion Valve t temperature, oC FPCS Freeze Pre-concentration System thk thickness, m LHE Latent Heat Exchanger v velocity, m/s LL_HE Liquid-Liquid Heat Exchanger x quality, % R22 Refrigerant 22 W power, kW SP State Point

Subscripts av average i inlet c cooling ice ice crnt carnot ini initial cj concentrated juice ise isentropic cmp compressor lat latent cnd condenser/condensation o outlet cw cold water r refrigerant e electrical rj raw juice evp evaporator/evaporation ss sugar solution fpd freezing point depression vol volume/volumetric

1. Introduction

Jaggery making is the oldest cottage industry in India. Jaggery and khandsari making crushed more than 20 to 30% of sugarcane [1]. It is reported that 7 million ton jaggery was produced in 2004. Per capita consumption of jaggery and sugar is 8.1 kg and 14.2 kg respectively [2]. It indicates that about 36% sweetener need is provided by jaggery. Conventionally jaggery is produced by evaporation of water in open pan/s. Furnace is fired using bagasse, which is residue of sugarcane, obtained during juice extraction. Furnace heat utilization efficiency is very low, which is ~15% for single [3], ~30% for two [4], and 50 to 60% for four pans [5]. It also depends on number of parameters like sizes of pan, furnace and chimney, flue gas flow patterns, orientation and air inlets, bagasse firing practices, etc. In addition to this, these units are mainly designed and developed through past experiences. Saving of bagasse gives additional revenues to the farmers. Chemicals like lime, phosphoric acid and hydros powder are used by jaggery makers to clarify juice [1,6,7]. Traces of these chemicals in the jaggery are harmful for human health. These key issues are addressed by Energy Efficient Freeze Pre-concentration Process. In this process, water is selectively freezed and separated from juice to form ice and concentrated juice. Freezing point of juice changes from -1.5 to -4.6oC [8] for 20 to 40oBrix. During this initial 63% water removal, bagasse is saved and that can be recycled in field for composting. Concentrated juice is obtained at low temperature. This juice is further concentrated using steam jacketed pan with vegetative clarificants. Altogether, it improves colour of jaggery from dark brown to golden yellow which has higher market value.

372 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381

2. Overview of Conventional Jaggery Making Process

In conventional jaggery making process, harvested sugarcane from field is stored near the crushing area. Juice is extracted by horizontal roller crusher operated using electric motor or diesel engine. Conventional jaggery making process with typical number of quantity is shown in Fig. 1.

Fig. 1: Conventional Jaggery Making

Typical extraction efficiency ranges from 60 to 70%. Residue of juice extraction, bagasse, contains about 45 to 55% moisture. It is sun dried upto 15 to 25% by spreading in open space. Juice is filtered to remove suspended fine bagasse particles and pumped to settling cum storage tank. As the earlier batch finishes, filtered juice is preheated to 70 to 85oC in pan and first scum is removed. Clarificants like milk of lime, phosphoric acid, hydros powder, mucilage of lady’s finger are added to improve clarification and quality of jaggery. Frothing and bubbling of juice is reduced by continuous stirring using manual scrapping at bottom of pan or rotating horizontal rod mechanism. Second scum is removed as concentration progresses. Total scum quantity ranges from 1.5 to 4% of juice [5]. Continuous stirring helps to prevent frothing, spillage of juice from pan and caramelization of sugar [9] by reducing hot spot formation as turbulence in juice instead of pool heating. Viscosity of syrup is tested by skilled person. Syrup from pan is poured in cooling and crystallizing pot. This cooled syrup is poured in moulds covers with wet cotton cloth or gunny bags. It facilitates easy removal of solid jaggery from moulds. This conventional jaggery making process may slightly vary from region to region. Quality of jaggery depends on variety of sugarcane, its cultivation, farming, practices applied in usage of water and fertiliser, boiling practices like use of clarificants, furnace firing practices, pan and furnace specifications etc. The number of open pan/s used for concentrating juice depends on severity of bagasse use. Some cane varieties are sugar rich while some are fibre rich. Single pan jaggery making with sugarcane having low fibre and high sugar content may require additional fuel other than bagasse. This issue was addressed by increasing number of pan for preheating and concentration. Two, three and four pan furnaces are reported in literature. It shows that furnace heat utilization efficiency increases with number of pans. Initial investment also increases with increase in number of operators. Quality of jaggery is still being questioned, as chemical clarificants are used to enhance colour of juice and hence colour of jaggery. Organic sugarcane cultivation and crushing same sugarcane for organic jaggery making using only vegetative clarificant showing huge potential in Indian market as well as for export. India has exported 1.4% of total jaggery and confectionary exported by all countries in 2012 [10]. This huge opportunity can be met by continuous and automated operation of small jaggery units. It will offer addition employment and help to improve status of debt ridden sugarcane farmers. These issues are addressed by Energy Efficient Freeze Pre-concentration of Sugarcane Juice using a Reversible Heat Pump. Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381 373

3. Freeze Concentration Systems

Water is removed in the form of ice from sugarcane juice by selective freezing. This process of water removal is shown by freezing curve in sucrose-water phase equilibrium diagram, Fig. 2.

Fig. 2: Sucrose-Water Phase Equilibrium Diagram (Mathlouthi and Reiser, 1995)

Sugarcane juice at room temperature and 20oBrix [5] is subcooled from point ‘a’ to ‘b’. Solidification of water commences, at point ‘b’, at -1.5oC, simultaneously concentration of remaining juice increases, during process ‘b’ to ‘c’. Due to dissolved sucrose in water, water gets freeze out at -1.5oC instead of 0oC if the water is pure. This drop in freezing temperature of water in juice is called as freezing point depression. Concentration of outlet juice depends on quantity of water frozen out and it is limited by eutectic temperature, which is -13.9oC at 63oBrix. Beyond this point, the whole juice gets solidified and aim of concentration of juice cannot be achieved.

Process a to b: subcooling of solution, temperature reduces from 30oC to -1.5oC Process b to c: freezing of water, temperature reduces from -1.5oC to -4.6oC for 20 to 40oBrix of solution

Ice formed by concentrating 1 kg solution from 20 to 40oBrix is estimated by mass and concentration balance, mice = mss.i . (1 - css.i / css.o) …(1) = 1 kg (1 - 20oBrix / 40oBrix) = 1 kg (1 - 0.5) = 1 kg x 0.5 = 0.5 kg

This shows that from 1 kg solution at 20oBrix, out of 800 g of water, 500 g water is removed in the form of ice, which is 63% of total water in the initial solution. 374 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381

Freezing of water inside the tube is reported by Miyawaki et al., 2005 [11] for coffee extract, tomato juice and sucrose solution. Solution is recirculated in closed loop arrangement. Water freezes layer by layer inside the circular tubes, subcooled from outside and after sufficient ice deposition, the whole system is dismantled to remove ice from the tubes. Sugar solution is concentrated from 8.9oBrix to 20.7oBrix in 90 min with 5.49 mm/h ice growth rate, inclusion is 0.65oBrix. Second sample of solution is concentrated from 41.4oBrix to 54.8obrix in 130 min with 3.04 mm/h ice growth rate, inclusion is 18.7oBrix.

Auleda et al., 2011 [12] developed a calculation methodology to design a multi-plate freeze concentrator for fruit juice concentration. Juice flows over the vertical parallel plates under gravity. Rane and Jabade 2005 [13,14] proposed freeze concentration of sugarcane juice using a heat pump and have shown that concentration of juice from 20 to o 3 40 Brix saves about 77% bagasse with improvement in quality. Specific power requirement is 17.2 kWhe/m water removal. Rane and Padiya, 2010 [15,16] showed two stage heat pump with external condenser for freeze concentration 3 of seawater desalination requires 9 to 11 kWhe/m water at COPc 8 to 12. Improved freeze pre-concentration system is investigated and compared for sugar inclusion, energy consumption and system cost.

4. FPCS using Reversible Heat Pump

Schematic of Freeze Pre-concentration System for sugarcane juice pre-concentration from 20oBrix to 40oBrix is shown in Fig. 3. This system consists of heat exchangers namely Liquid-Liquid Heat Exchanger, LL_HE, two Latent Heat Exchangers, LHE and Concentrated Juice Heat Exchanger, CJ_HE. Process of cooling and heating in LHE is shown in Table 1.

Table 1: Process of Cooling or Heating in LHE during Each Half Cycle

LHE Work / In/Out First Half Cycle Process Second Half Cycle Process LHE1 Work as Evaporator Condenser Inlet Subcooling of raw juice, freezing Sensible and latent heating of ice of water, concentration of juice, Melting of ice subcooling of ice Outlet Concentrated juice Water

LHE2 Work as Condenser Evaporator Inlet Sensible and latent heating of ice Subcooling of raw juice, freezing of Melting of ice water, concentration of juice, subcooling of ice Outlet Water Concentrated juice

LL_HE precools the sugarcane juice using streams of concentrated juice coming from CJ_HE and cold water coming from LHE during each half cycle. One LHE is used freezing of water from juice flow and another for melting of ice. They are operated alternately as evaporator and condenser. CJ_HE recovers the superheat of refrigerant for heating of concentrated juice coming from evaporator. Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381 375

Fig. 3: Heat Pump based Freeze Pre-concentration of Sugarcane Juice

This system consists of 1 three way valve, V1, for directing juice flow to LHE, working as evaporator and 3 four way valves, V2, V3 and V4. Valve, V2, for directing concentrated juice flow coming from evaporator to LL_HE and two valves, V3 and V4 for directing refrigerant flow in heat pump circuit. R22 compressor with 1.5 TR is selected for investigations on inclusion and its repercussions on system cost. SS circular tube OD 9.52, 1 mm thick, 6 m long tubes in series are used in Tube-Tube type Heat Exchanger.

4.1. Working Principle

Fresh sugarcane juice at room temperature about 27oC enters in the evaporator, LHE1, through LL_HE where it gets pre-cooled to -1.5oC before entering into the evaporator, LHE1. At freezing temperature of juice, which is -1.5oC, ice layer starts to build up inside the tube. It will start to build up pressure drop, as a result pressure drop across the evaporator will increase. This reduces the evaporator temperature, as ice thickness has low thermal conductance. Expected thickness of formed ice in the system is 1 to 3 mm. Simultaneously, in condenser, LHE2, ice gets heated in two steps, comprising sensible heating from -4.6oC to 0oC, followed by latent heating, at 0oC. At certain low evaporator pressure, all three way and four way valves are operated for the second a half cycle of the system. During second half cycle, LHE1 acts as condenser and LHE2 will acts as evaporator. Refrigerant circuit removes heat from the evaporator and rejects it into condenser. Sugarcane juice circuit gives heat in evaporator and ice receives back in condenser. Compressed refrigerant enters into the CJ_HE and dissipates superheat for heating concentrated juice coming out from evaporator, LHE1, and then used to precool incoming juice. Refrigerant vapour are further cooled by melting ice in condenser, LHE2. Liquid refrigerant from LHE2 is directed to four way valve, V3 and expanded into the evaporator, LHE1, through expansion valve. It receives heat from 376 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381

precooled juice. Saturated vapours of refrigerant are sucked by compressor and half cycle repeats after switching of valve for back to the first half cycle.

5. Calculations

Analysis of Freeze Pre-concentration System is presented here for mass flow rate, heat duty and inclusion estimation. Following are the assumptions to simplify calculations. • Negligible superheat in evaporator and subcooling in condenser, negligible pressure drop in heat exchanger • Minimum temperature approaches in LHE, 3oC • Compressor isentropic efficiency is 70% • Heat transfer across streams of fluids in valves is neglected • Ambient heat gain is neglected

Temperature of juice at inlet of evaporator is -1.5oC and it is to reduce to -4.6oC using evaporator. Refrigerant temperature in evaporator becomes -7.6oC. Melting temperature of ice in condenser is 0oC. Refrigerant condensation temperature becomes 3oC. Temperature lift of cycle is 10.6oC.

Mass balance of material across evaporator, Raw juice = concentrated juice + ice/water mfrj = mfcj + mfice

Rearranging for water/ice flow, mfice, mfice = mfrj - mfcj …(2)

Concentration balance of material across evaporator, mfrj . crj = mfcj . ccj + mfice . cice …(3)

Initially, it is assumed that negligible sugar inclusion in ice. Hence, Eqn 3 may reduce to, mfrj . crj = mfcj . ccj

Rearranging for concentrated juice flow, mfcj, mfcj = mfrj . crj / ccj …(4)

Mass flow rate of water, mfice, during pre-concentration, using Eqn 2 and 4, mfice = mfrj . (1- crj / ccj) …(5)

Heat balance across evaporator, Refrigerant cooling effect = subcooling of concentrated juice + ice formation Qc = Qcj + Qice …(6)

Cooling capacity of compressor at evaporator -8oC and condenser 3oC is estimated from manufacturers chart, Qc = Qcj + (Qlat.ice + Qice.sen)

Qc = mfcj . cpcj . (trj.evp.i - tcj.evp.o) + mfice . [hlat.ice + cpice . (trj.evp.i - tcj.evp.o)] …(7)

Mass flow rate of raw juice, mfrj is calculated using eqn 4. Qc mfrj= crj crj …(8) . cp . trj.evp.i - tcj.evp.o + 1- . hlat.ice+ cp . trj.evp.i - tcj.evp.o ccj cj ccj ice Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381 377

Ratio of sensible enthalpy of concentrated juice to the latent heat of ice is 2.0%, hence ice growth rate is not affected much by subcooling of concentrated juice. Similarly, sensible enthalpy of ice to latent heat of ice is 2.4%. Hence, both sensible heat can be neglected to get a rough estimate of mass flow rate of raw juice, mfrj.

Mass flow rate of refrigerant, mfr, mfr = Qc / (hd - hc) …(9)

Compressor work, Wcmp, heat duty of concentrated juice, Qcj_he, and condenser duty, Qcnd, are calculated from known mass flow rate of refrigerant. Cooling coefficient of performance, COPc, COPc = Qc / Wcmp …(10)

Carnot efficiency, hcrnt, hcrnt = COPc / COPcrnt …(11)

Heat duty of sugarcane juice in LL_HE, Qrj.llhe, is calculated as follows, Qrj.llhe = mfrj . cprj . (trj.llhe.i - trj.llhe.o) …(12)

Heat duties of concentrated juice, Qcj.llhe, and cold water, Qcw.llhe, are estimated assuming 50% contribution to heat transfer by each flow stream.

Power loss in cycling of thermal mass, Qth.lhe = [(mflhe.ss . cpss + mflhe.cu . cpcu) . (trj.lhe.i - tcj.lhe.o)]/timehlf.cyc …(13)

It is deducted from cooling effect, Qc, to obtain actual cooling available for freezing of water. Heat pump cycle on t-s and p-h diagrams for R22 refrigerant are shown below,

Fig. 4: t-s and p-h diagrams for FPCS with RHP

Based on ASHRAE, 2013 [17] data, performance of cycle is estimated. Carnot COP for lift of 10.6oC is 25.1.

Sugar Inclusion of Ice Average Distribution Coefficient, ADC, is defined as the ratio of concentration of sugar in ice to the concentration of solution. ADC = cice / css …(14)

378 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381

Average Distribution Coefficient, ADC, is estimated using empirical correlation provided by Chen et al., 2014 [18]. It applies for flow of solution over vertical flat surface.

2 vice … (15) ADC = -0.1 + 0.32 . tfpd - 0.04 . tfpd + 0.12 0.5 vss

Average distribution is calculated for different juice velocity and ice growth rates. It is shown in Fig. 5.

Fig. 5: ADC vs Sugarcane Juice Velocity at different IGR

Low ice growth rate, IGR, at any velocity of juice favours low inclusion. Mass transfer of sugar gets sufficient time to travel from ice-juice interface to the juice. Faster the ice formation, less will be the sugar transport time and sugar get included in the ice. This is not favourable situation, as sugar get lost in water. Higher velocity than 2 m/s has not more effect on inclusion for 1 micron/s IGR. Case 1, 2 and 3 are discussed in next section.

6. Results and Discussions

Water removal rate for different outlet concentrations is analyzed. Ways of reducing the sugar inclusion in ice are investigated and analyzed for their effect on sugar loss and system cost. Benefits of freeze pre-concentration are discussed.

6.1. Limiting Concentration for Freeze Concentration System

Freeze concentration from 20obrix to 33obrix removes about 50% of total water available in juice. Fig. 6 shows the variation in water quantity removed during change in concentration starting with 20oBrix. Dotted line indicates the water quantity remaining in juice. Shaded portion shows the area of freeze pre-concentration from 20oBrix to 40oBrix. During this concentration change, 62.5% water is removed in the form of ice and remaining 37.5% water is to be removed by steam jacketed boiling. Increase in outlet concentration from 40oBrix to 50oBrix, 13% more water get removed. This rate of water removal may not be justified by increase in sugar loss. Three cases are presented in the next section. Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381 379

FPCS Zone Open Pan Boiling

Fig. 6: Water Removed/Remained from/in Juice vs Outlet Concentration

Limiting factors for outlet concentration are inclusion in ice and eutectic point, 63oBrix. Inclusion increases as the inlet juice concentration increases. It also depends upon velocity of juice and ice growth rate. Hence, freezing close to the eutectic point is not considered due to high sugar loss in water.

6.2. Analysis of Sugar Loss and System Cost

Mass flow of juice is estimated using Eqn 9 for known cooling capacity of compressor. Inclusion is estimated using correlation given by Chen et al., 2014. Weighted average of inclusion is calculated at inlet and outlet flow for half cycle. As the inclusion for initial condition is 19.1oBrix and 47.9% of actual available sugar in raw juice is lost. It is too high and reduces recovery of jaggery. This operation is not economical. Hence, velocity of juice is increased to 1.0 m/s by recirculation of same juice using small capacity pump. MathCAD program was run to calculate inclusion and system cost.

Table 2: Comparison of Inclusion and System Cost

Case Condition vjc.evp.i vice vcj.evp.o cice cice.av losssug.ice dcice.av Costini o o m/s μm/s m/s Brix Brix % %, wrt case 1 %, wrt case 1

Initial 0.60 3.65 0.60 17.0 1 19.1 47.9 -- -- Final 0.82 3.65 0.82 40.4

Initial 1.00 3.65 1.00 14.5 2 16.9 42.2 -11.5 4.5 Final 1.35 3.65 1.35 36.1

Initial 2.00 1.82 2.00 10.1 3 12.9 32.3 -32.5 58.0 Final 2.70 1.82 2.70 28.6

380 Milind V. Rane and Dinesh B. Uphade / Energy Procedia 90 ( 2016 ) 370 – 381

Inclusion is reduced to 16.9oBrix from 19.1oBrix, sugar loss in water is 42.2% of total available sugar in raw juice. Energy consumption increased by 19% due to an additional pump. Hence, next option is to decrease ice growth rate by increasing heat exchange area. It increases cost of heat exchanger with recirculation pump to overcome pressure drop. Program was run for this condition, it indicates that cost of latent heat exchangers get doubled with sugar loss of 32.3% of available sugar in raw juice. Further reduction in inclusion requires additional heat exchange area. Loss of sugar gets reduced from 47.9% to 42.2% and to 32.3% in above investigated cases. Theoretical system COPc is 18, accounting cycling of thermal mass and ambient heat gain expected COPc is 9 to 3 12. Specific energy consumption is 9 to 11 kWhe/m water. Carnot efficiency of heat pump cycle is 35 to 48%.

6.3. Advantages of FPCS are as follows,

3 • Low specific power consumption 9 to 11 kWhe/m water removal • Saving of bagasse upto 77% of produced bagasse. It gives additional revenue to farmers • Reduction in area required for jaggery making unit by 60% • Quality of jaggery gets improved. Colour of jaggery gets improved without using chemicals • Reduction in pan size, which is required for boiling of concentrated juice • Operation of system is also possible using solar photo-voltaic cells • Automated operation reduces number of workers required to handle boiling process

7. Conclusions

Conventional jaggery making process consumes large quantity of bagasse due to low furnace heat utilization. Boiling of juice at high temperature causes hot spots, it leads to caramelization of sugar. It gives dark brown colour to jaggery. Hence, jaggery makers uses chemicals to improve clarification of juice. These issues are addressed by improved Freeze Pre-concentration System. It shows better prospects for efficient way of jaggery making. Researchers reported use of heat pump for concentration of juice, but sugar lost in inclusion and system cost are high. 3 Energy consumption of improved FPCS system is 9 to 11 kWhe/m water removal at COPc 9 to 12. Partial heat removal of condenser heat helps to maintain condenser temperature at 3oC and it is used for heating concentrated juice. It improves cycle COP and overall energy efficiency of FPCS. Challenge of excess condenser heat to melt ice is overcome by this improved FPCS. Quality of jaggery is improved by reducing exposure of juice to low temperature during 63% water removal. Recycling of saved bagasse in field improves organic content of soil and productivity of sugarcane improves. Further study on effect of removal of juice composition like proteins and polyphenols in syrup, after pre-concentration, on quality of jaggery and experimental investigations for actual specific energy consumption and inclusion will be done in future.

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