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INSTRUMENTATION

Automation is playing an ever increasing role inthe global economy. It is the core infrastructure ofevery process industry and sugar industry is not anexception. The developments in instrumentation andautomation are constantly touching to meet theincreasing demand of the sugar industry for costeffective and competent solutions withoutcompromising on quality. The instrumentation andcontrol system in sugar industry invites overallchanges in sensors, transmitters, control systemcomponents and control systems.

HIGHLIGHTS OF PERFORMANCEImprovements in working performance ofpressure reducing stations

The mill at Sahyadri SSK has two pressurereducing stations (32 to 7 Kg/cm2 and 7 to 1 Kg/cm2). The mill has installed pressure reduction andstabilization systems for these stations in the crushingseason 2010-11. The mill faced critical problems inpressure regulation of the system corresponding to7 to 1 Kg/cm2. The steam pressure at outlet was 10PSI and could not be increased upto 15 PSI. Thiswas affecting the boiling house operations adversely.On inspection of both pressure reducing stations, itwas noticed that set point of pressure reducing station(32 to 7 Kg/cm2) was 4.5 Kg/cm2 due to the impropersetting of safety valve. Secondly, the problems inelectronic cards were noticed. Changes in the controlcards were done and the appropriate resetting ofsafety valve corresponding to pressure reducingstation (32 to 7 Kg/cm2) was carried out. Then, boththe pressure reducing control systems were retunedand set to maintain steam pressure at outlet ofpressure reducing station (7 to 1Kg/cm2) at 15 PSIwith considerable constant pressure at boilers andthe consistency in boiling house operation wasachieved.

Effective modification in imbibtion water flowcontrol system

The imbibition water flow control system installedin Purna SSK was based on the measurement ofchest pressure of penultimate mill turbine andaccordingly the imbibition water flow is controlled

through dynodrive. During 2012-13, mill had replacedthe steam turbine with variable frequency drivecommon for penultimate and the last mill. The mill hasrequested the Institute to interface this VFD toimbibition water flow control system. The necessarymodifications in the electronic cards of the system weredone. The modified imbibition water flow controlsystem was commissioned as per the standardinstrumentation practices. The system is tuned toachieve effective imbibition. The working performanceof the control system was found satisfactory throughoutthe season. This has helped the mill to maintain theconsistency in bagasse moisture and pol, leading toimprovements in boiler efficiency.

Accurate flow meaurements in co-generationDuring 2011-12, Datta Shetkari SSK had

completed the modernization of sugar mill and co-generation project. The co-generation project is onBOT basis. As per the agreement between sugar milland M/s. Urjankur, the steam at 2.7 ata and electricityrequired for the plant is to be given by M/s Urjankur.In addition steam and power consumed than the millhas to pay extra for the same. Two flowmeters wereinstalled in 32" extraction line - one near to the millside and one at co-generation plant for themeasurement of process steam to the mill. During2011-12, the mill has approached the Institute forverification of flowmeters readings. The engineersverified the calibration of flowmeters with standardcalibrators and were observed to be on higher side.This was done as the flowmeter readings were goingout of range. Further investigations revealed that co-generation flowmeter was partially jammed near flowsensor and installation of other flow sensor was not asper standard instrumentation practices. The correctionwas not possible during the season as it requiredclosure of plant. Hence, the removal of jamming dueto burrs and proper installation of flow sensor wascarried out in 2011-12 off-season. Flowmeters wereshowing erratic readings even in 2012-13 season. Thiswas due to the error in differential pressure calculationsrelated to flow sensors. This issue was discussedthoroughly with flow sensor manufacturer and revisedcalculations were obtained from the manufacturer.Both the flowmeters were recalibrated with revised

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data. Presently, the flowmeters are showing accurateresults, which helped the mill to pay the appropriatecost for steam.

Use of thermal imaging for predictivemaintenance

Thermal imaging is a growing technology that hasmany advantages. Its use has revolutionized predictivemaintenance inspection programs virtually for alltypes of industries. A thermal imaging camera is areliable non contact instrument which is able to scanand visualize the temperature distribution of entiresurfaces of machinery and electrical equipmentquickly and accurately.

During 2012-13 season, trials of thermal imagingcamera were taken in Malegaon SSK.Thermography of major electrical equipments in co-generation plant was taken. Study of these graphsindicated priority areas for preventive maintenanceof the electrical equipments. In one of air circuitbreaker for FD fan, many hot spots were observedwhich indicated overloading situation of fan and calledfor an immediate action. This problem detection couldnot possible even in experienced skilled electriciansor by any direct contact type temperaturemeasurement system. Detail thermography reportsfor all major equipments and proposed actions wereprepared. Similarly, this knowledge will bedisseminated to other sugar mills in future.

Measurement traceability in sugar industryEstablishing and maintaining the measurement

traceability is the primary requirement of calibration

laboratory. The reasons for traceable measurementsextend well beyond the immediate needs of thecalibration laboratories. Measurement traceability isan unbroken chain of comparisons from themeasurements being made to a recognized nationallegal standard. It is a must for all parameters. Atraceable calibration is achieved when each instrumentand standard in a hierarchy stretching back to NationalStandard. In sugar industry, for ensuring accuratemeasurements of various process parameters, thetraceability of the same is required in ISO certification.The department is well equipped with standardcalibrators which are being calibrated through NABLaccredited laboratory. The measurement traceabilityof total 277 instruments through calibration work wasensured in Vaidyanath SSK, Manjara Shetkari SSK,Chhatrapati SSK, Bhaurao Chavan SSK Unit-I andUnit-II, Mula SSK, Sahyadri SSK, Vikas SSK,Ajinkyatara SSK, Baramati Agro SSK, LokmangalAgro Ind., Purna SSK and Rena SSK.

Instrumentation and automation in co-generation and distillery plants

In co-generation and distillery projects, the state-of-the-art instrumentation has been considered forthe safe and smooth operations. The department hadcarried out various activities in these projects for idealmeasurement and control systems detailed as under:

EXTENSION AND ADVISORY SERVICESTo improve the status of instrumentation, 823

instruments of 44 sugar mills were overhauled andcalibrated at the mill or at the Institute. The detailsare as given in table 52.

Table 52 : Details of activities for ideal measurement and control system

Name of the project ActivitiesCo-generation Co-ordination meetings regarding Instrumentation and Automation Bhimashankar SSK with manufacturers / suppliers Vaidyanath SSK Inspection of SWAS, transmitters, O2 analyzers etc. Manjara Shetkari SSK Conducted Pre-FAT & FAT of DCS system

Supervision and guidelines in pre-commissioning activities

Distillery SMSM Patil SSK Checking and approval of P&I diagrams, Instrument index sheets, Vikas SSK Panel drawings Vithalrao Shinde SSK Inspection of PRDS station, glass/metal tube rotameters, globe type control Datta Shetkari SSK valves, magnetic flowmeters, butterfly valves, float type level gauges etc. Kumbhi Kasari SSK Conducted Pre-FAT and FAT for PLC system

Supervision and guidelines in pre-commissioning activities

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Mill house instrumentationInstruments related to mill house instrumentation

systems were rectified, standardized andcommissioned in the following sugar mills: Bhaurao Chavan SSK Purna SSK RP Ghodganga SSK Manjara Shetkari SSK Anuraj Sugars Chhatrapati SSK Sahyadri SSK Shankar SSK, Sadashivnagar Vaidyanath SSK Gajanan SSKThis included ACFC system, IWFC system, flow

meters, pressure transmitter, pressure indicator,speed indicator, auto/manual stations, dynodrivecontrollers, load indicator, pressure gauges etc.

Boiler house instrumentationInstruments related to boiler house instrumenta-

tion systems were rectified, standardized and com-missioned in the following sugar mills Majalgaon SSK Bhaurao Chavan SSK Purna SSK RP Ghodganga SSK Chhatrapati SSK Manjara Shetkari SSK Malegaon SSK Mula SSK Vaidyanath SSK Anuraj Sugars Jarandeshwar SugarThis included flow meters, multi-point temperature

indicator, pressure gauges, drum level transmitter,microprocessors based controllers, draft gauges etc.

Power house instrumentationInstruments related to power house

instrumentation systems such as steam flow meters,temperature indicators, pressure gauges etc. wererectified, standardized and commissioned in followingsugar mills

Majalgaon SSK Bhaurao Chavan SSK RP Ghodganga SSK Chhatrapati SSK Manjara Shetkari SSK Malegaon SSK Mula SSK Datta Shetkari SSK Vaidyanath SSK

Boiling house instrumentationInstruments related to boiling house were

rectified, standardized and commissioned in followingsugar mills Majalgaon SSK Dr. B Ambedkar SSK Jarandeshwar Sugars Bhaurao Chavan SSK Purna SSK RP Ghodganga SSK Chhatrapati SSK Manjara Shetkari SSK Vaidyanath SSK Sahyadri SSK Malegaon SSK Mula SSK Datta Shetkari SSKThis included flow meters, vacuum/compound/

temperature gauges, temperature indicator, pressuretransmitter, pressure controller etc.

Laboratory instrumentation Instruments of 36 sugar mills were rectified andstandardized. These include brix hydrometers, poltubes, thermometers, pH meter, polarimeter,conductivity meter, spectrophotometer, microscopeetc.

Distillery instrumentationDistillery process instruments and calibrators of

Ajiyankatara SSK, Malegaon SSK and Mula SSKwere standardized and re-commissioned. Theseinclude steam flow transmitters, steam flow indicatorcum totalizers, temperature controller and pH meter.