Discrete Event Simulation Approach for Energy

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Procedia CIRP 00 (2017) Procedia CIRP000–000 78 (2018) 2–7 www.elsevier.com/locate/procedia

6th CIRP Global Web Conference “Envisaging the future manufacturing, design,Web technologies and systems in innovation era” 6th CIRP Global Conference “Envisaging the future manufacturing, design, technologies and systems in innovation era” Discrete Event Simulation ApproachMay for2018, Energy Resource 28th CIRP Design Conference, Nantes,Efficient France

Discrete EventManagement Simulation Approach forPulp Energy Efficient Resource in Paper & Industry A new methodology to analyze in thePaper functional and physical architecture of Management & Pulp Industry b Keshari N. Sonsale , Brij K.product Sharmab, Sanjay Pohekarc existingAnupam products fora,a,*,anAnand assembly oriented familyD.identification b b c Anupam Keshari *, Anand N. Sonsale , Brij K. Sharma , Sanjay D. Pohekar Department of Mechanical Engineering, Motilal Nehru National Institute of Technology, Allahabad, 211004, India School of Engineering andMotilal Technology, University, Jaipur, 302025, India 211004, India Paul Stief *, Jean-Yves Dantan, Alain Etienne, Ali Siadat Department of Mechanical Engineering, Nehru Poornima National Institute of Technology, Allahabad, a

b

a

b Symbiosis Center for Researchand andTechnology, innovation, Poornima Symbiosis University, International (DU),302025, Pune, 412115, School of Engineering Jaipur, India India c École Nationale Supérieure et for Métiers, Artsand et Métiers ParisTech, LCFC EA 4495, 4(DU), Rue Augustin Fresnel, Metz 57078, France Symbiosisd’Arts Center Research innovation, Symbiosis International Pune, 412115, India * Corresponding author. Tel.: +91-889-058-9171. E-mail address: [email protected] c

* Corresponding author. Tel.: +91-889-058-9171. E-mail address: [email protected] * Corresponding author. Tel.: +33 3 87 37 54 30; E-mail address: [email protected]

Abstract Abstract Abstract To improve energy efficiency of a Paper & Pulp industry, full capacity utilization of the processing equipment and diverse energy source utilities are promoted, while same processing diversefull rawcapacity materials, meeting of strict processingequipment time requirements, seamless To improve energy efficiency of atime Paper & Pulp of industry, utilization the processing and diverse energymaterial source Inflow today’s business environment, the trend towards more product variety and customization is unbroken. Due to this development, the need of andare obtaining required quality are important concerns to be fulfilled. is similar to a resources management problem while utilities promoted, while product same time processing of diverse raw materials, meetingThis of strict processing time requirements, seamless material agile and reconfigurable production systems emerged to cope with various products and product families. To design and optimize production energy is considered as one ofproduct the measurable resources, wherein estimation of energy consumptions aspect. Discretized flow and obtaining required quality are important concerns to be fulfilled. This is similar toisa crucial/complicated resources management problem while systems as well asconsumption to choose the optimal product matches, product analysis methods are needed.products Indeed, at most of the intermediate known methods aim to form consumed byestimation unit amount of intermediate different processing energyofisenergy considered as one of (approximate the measurableenergy resources, wherein of energy consumptions is crucial/complicated aspect. Discretized analyze a productisorutilized one product family on the physical level. Different product energy families,estimation/analysis. however, may differThe largely in terms the number and stages) here(approximate with discrete event simulation for unit consumed research dealsofwith aprocessing real time form ofconcept energy consumption energy consumed by amount of intermediate products at different intermediate nature of components. This fact impedes an efficient comparison and choice of appropriate product family combinations for the production working Paper &isPulp industry management problem, wherein overallenergy energyestimation/analysis. consumption rate and production rate were for stages) concept utilized here resource with discrete event simulation for consumed The research deals withanalyzed a real time system. A new methodology is proposed to analyzereduction existing products in view ofstation(s). their functional physical architecture. The aim is tovarying cluster some commonly situation of efficiency of the processing Energyand efficient solutions are evaluated working Paper & occurring Pulp industry resource management problem, wherein overall energy consumption rate and production rate were with analyzed for these products in new assemblypercentage oriented product for theresources optimization of existing assembly lines on/off and thepaper creation of futureEnergy reconfigurable production flow (varying of raw families material) and management options (turning some commonly occurringthesituation of efficiency reduction of the processing station(s). Energy efficient solutionsmachines). are evaluated with efficient varying assembly systems. Based on Datum Flow Chain, the physical structure of the products is analyzed. Functional subassemblies are identified, and solution which minimum loss in production rate and material flow ison/off suggested implementation. production flowensures (varying the percentage of raw material) andminimizes resourcesdisturbances managementinoptions (turning paperformachines). Energy efficient a functional analysis is performed. Moreover, a hybrid functional and physical architecture graph (HyFPAG) is the output which depicts the solution which ensures minimum loss in production rate and minimizes disturbances in material flow is suggested for implementation. similarity between product families by providing design to both, production planners and product designers. An illustrative © 2018 The Authors. Published by Elsevier B.V. This is ansupport open access article under thesystem CC BY-NC-ND license © 2018 The Published Elsevierthe B.V. This is an open accessAn article under the BY-NC-ND license families of steering columns of example of a Authors. nail-clipper is used by to explain proposed methodology. industrial caseCC study on two product (https://creativecommons.org/licenses/by-nc-nd/4.0/). © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) thyssenkrupp Franceunder is then carried out toofgive a first industrial evaluation of the proposed Selection andPresta peer-review committee of the the 6th 6th CIRP Globalapproach. Web Conference Conference “Envisaging “Envisaging the the future future (https://creativecommons.org/licenses/by-nc-nd/4.0/). Selection peer-review underbyresponsibility responsibility of the the scientific scientific committee of CIRP Global Web ©manufacturing, 2017 Theand Authors. Published Elsevier B.V. design, technologies and systems in innovation era”. Selection and peer-review under responsibility of the scientific committee of the 6th CIRP Global Web Conference “Envisaging the future manufacturing, design, technologies and systemscommittee in innovation era”. Peer-review under responsibility of the scientific of the 28th CIRP Design Conference 2018. manufacturing, design, technologies and systems in innovation era”. Keywords: Energy Efficiency; Discrete Event Simulation; Resource Management; Paper & Pulp Industry. Keywords: Assembly; Design method; Family identification Keywords: Energy Efficiency; Discrete Event Simulation; Resource Management; Paper & Pulp Industry.

1. Introduction [4]. Paper industries are employing different type of pulp and 1. Introduction of the product range depending and characteristics manufactured and/or bleaching on type of raw materials 1. Introduction [4]. Paper processes industries are employing different type of pulp and assembled in this system. In this context, the main challenge in The paper and pulp industries manufacture pulp, paper, requirement of pulp finish for final paperofmaking [5]. Change bleaching processes depending on type raw materials and Due to the fast development in the domain of modelling and analysis is now not only to cope with single paperThe board, andand other based products by using the of paper qualities also lead to vary subpaper pulpcellulose industries manufacture pulp, paper, requirement of pulp finish for final paper resources making [5].and Change communication and an ongoing trend ofwastes digitization products, a limited product range or existing product families, wood, bagasse, wastes, paper as and raw resources and processing time.resources Moreover, paper board, andagriculture other cellulose based products byetc. using the of paper quantities qualities also lead to vary andenergy subdigitalization, manufacturing enterprises as areone facing important but alsoboth to be able to analyze and to compare products to define materials. Paper Industry is wastes, considered of etc. the top six being a resource and processing a saleable product in paper and pulp wood, bagasse, agriculture paper wastes as raw resources quantities and time. Moreover, energy challenges in today’s market environments: a continuing new product families. can be observed that classical existing energy intensive Aluminum, Cement, industry [6], effectiveIt utilization variable options materials. Paper industries Industry islike considered as one of theFertilizer, top six being both a resource and a saleableofproduct in energy paper and pulp tendency towards reduction of product development times and product families are regrouped in function of clients or features. Iron Steel industries and GlasslikeIndustries [1,Cement, 2]. Because of (steam intermediate products use energy steam energy, energyand intensive Aluminum, Fertilizer, industry energy, [6], effective utilization of variable options shortened product lifecycles. In addition,paper there is an increasing However, assembly oriented product families are hardly to find. environmental to economize is electrical energy and bio energy) and fulluse capacity Iron and Steelissues and orGlass Industries [1, productions, 2]. Becauseit of (steam energy, intermediate products steamutilization energy, demand of customization, being at the same time in a global On the product family level, products differ mainly in two necessary to achieve thetobest possiblepaper energy utilization it[3]. of the machineries always been important improve environmental issues or economize productions, is electrical energy andhave bio energy) and full capacitytoutilization competition with competitors all over the world. This trend, main characteristics: (i) the number of components and (ii) the There is a large energythe efficiency potential yet to be exploited energy efficiency. The total site must highly integrated and necessary to achieve best possible energy utilization [3]. of the machineries have always beenbeimportant to improve which is inducing the development from macro to micro type of components (e.g. mechanical, electrical, electronical). There is a large energy efficiency potential yet to be exploited energy efficiency. The total site must be highly integrated and markets, results in diminished lot sizes due to augmenting Classical methodologies considering mainly single products product varieties (high-volume to by low-volume production) [1]. access or article solitary, existing product families analyze the 2212-8271 © The Authors. Published Elsevier B.V.This is an open underalready the CC BY-NC-ND license(https://creativecommons.org/licenses/by-nc-nd/4.0/). Selection and peer-review under responsibility of the scientific committee of the 6th CIRP To cope with this augmenting variety as well as to be able to product structure on a physical level (components level) which 2212-8271 © The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND Global Webpossible Conferenceoptimization “Envisaging the future manufacturing, design, technologies and systems in innovation era”.of the scientific identify potentials in the existing causes difficulties regarding an efficient and license(https://creativecommons.org/licenses/by-nc-nd/4.0/). Selection and peer-review under responsibility committee definition of the 6th CIRP doi:10.1016/j.procir.2017.04.009 Global Web Conference the future manufacturing, technologiescomparison and systems inof innovation era”. product families. Addressing this production system, it“Envisaging is important to have a precise design, knowledge different doi:10.1016/j.procir.2017.04.009 2212-8271 © 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection and peer-review underPublished responsibility of theB.V. scientific committee of the 6th CIRP Global Web Conference “Envisaging the future manufacturing, 2212-8271 © 2017 The Authors. by Elsevier design, technologies and systems era”. Peer-review under responsibility of in theinnovation scientific committee of the 28th CIRP Design Conference 2018. 10.1016/j.procir.2018.08.324

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Anupam Keshari et al. / Procedia CIRP 78 (2018) 2–7 Keshari et al. / Procedia CIRP 00 (2018) 000–000

optimised [7]. Towards this, in the paper industry, a series of policies have also been introduced and implemented at Government levels [8]. Paper and pulp industry have been attempting to deploy sophisticated energy management techniques to optimise energy supply, improve energy efficiency or identify possibilities for cascading energy consumption within production processes [10, 11], thereby enhancing competitiveness [12]. Thus, resources management becomes one of the essential tasks which directly/indirectly affect the energy efficiency of the paper & pulp plant. To improve energy efficiency, maximum capacity utilization of the processing equipment and diverse energy source utilities are also promoted, while same time processing of diverse raw materials, meeting of strict processing time requirements, seamless material flow and quality measures are important concerns to be taken care of. To estimate overall energy consumption rate in such complex problem scenario with varying production flow rate and resource management options, discretized form of energy consumption (energy consumed by intermediate products in unit time) is utilized through discrete event simulation. Wherein, energy is considered as one of the measurable resources. Quantities of raw material, resources, intermediate pulp products and energy used by each single machineries/equipment are quantized on per minute basis. The utilized data are sourced from OEM (Operations and Equipment Management) data for a typical recycling Paper & Pulp industry plant under modernization. Uncertainty levels of 5 % have been imposed during the calculations. Quantized data sets are utilized to perform simulations of overall production flow and energy consumption. And, its usage is presented to search energy efficient resource management options in some commonly occurring situations of energy efficiency reduction.

web determines the properties of the paper produced. Head box of paper machine continuously spreads pulp on wire section. On wet end wire part, paper dryness increases from 0.6 % to 15 % by means of gravity. Thereafter the web passes through Wet end press Part which applies pressure on paper web for water removal and contributes for uniformity and better sheet formation. Here 42-44 % of paper dryness is achieved. The web then passes through Paper Dryer Part which removes further water and achieves dryness up to 94 %. Here a controlled flow of saturated steam is used for drying the web. Then the Paper Calendar applies mechanical action for the improvement of smoothness of the paper by a series of pressured rollers. After this the Paper Pope Reel winds the continuous paper sheet onto a spool to produce jumbo rolls called "parent reels" or “master roll” that are ready for further processing. Table 1. The processes involved in sequence to transform the paper waste into new paper master roll. Sl. Process Name Process Mass of pulp Energy consumption Mass No. Type processed (MJ/minute) percentage (MT/minute) Electrical Steam of pulp (%) 1 2 3 4 5 6 7 8 9 10 11 12 13

2. Problem Definition 2.1

Waste paper recycling and processes description

Paper making essentially has two process domains, firstly creation of pulp from fibre and then a fine spreading of this pulp and drying in successive stages. Recycling industry uses waste paper as the source of secondary fibre [13]. However, the processes involved in paper recycling can be grouped in three stages (Table 1). At first stage, De-inking plant (DIP) removes ink from the waste paper to enhance brightness. The processes include De-baling, Sorting, Pulping, Cleaning & Screening, De-inking, Flotation and Bleaching etc. In the next stage of Refining, Chemical & Miscellaneous processing, mechanical action is applied on pulp fibres for improvement of paper properties like burst factor and tensile strength. Here the fibre surface will be exposed for the formation of hydrogen bonding whereby paper formation and sheet properties are enhanced. At third stage of processing, these refined fibres are subjected to a control process called Approach Flow which takes stock from feed chest and draws it at Head box for formation of paper sheet. Cleaned and deaired pulp flow then reaches the wire section. Wet end Wire Part is used for formation of paper web. The quality of this

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14 15

Drum Pulping HD cleaning Coarse screening Dump Tower stay LC cleaning First Stage Floatation LC fine screening Thickening 1 Dispersing Bleaching Tower stay Second Stage Floatation Thickening 2 Bleaching Reactor processing Storage Tower stay Refining, Chemical & Miscellaneous processing

16 Approach Flow 17 Wet end Wire Part 18 Wet end Press Part 19 Paper Drying 20 Paper Calendar 21 Paper Pope Reeling

Cont. Cont. Cont. Cont. Cont. 12 min

0.321 0.307 0.263 0.259 0.259 0.259

27 1 21 0 15 22

889 0 0 0 0 0

100 95.6 81.8 80.8 80.8 80.6

Cont. Cont. Cont. 60 min

0.240 0.238 0.232 0.220

19 5 93 1

0 0 633 0

74.8 74 72.1 68.4

8 min

0.220

19

0

68.4

Cont. 30 min

0.204 0.198

12 0

0 549

63.5 61.7

Cont.

0.198

10

0

61.7

Cont.

0.168

31

466

49.7

Cont. Cont.

PM1 PM2 PM1 PM2 PM1 PM2 PM1 PM2 0.129 0.074 17 0 5 0 40.2 23 0.126 0.072 20 0 7 0 39.2 22.4

Cont.

0.126 0.072 19

Cont. Cont. Cont.

0.126 0.072 23 358 0.126 0.072 6 0 0.121 0.069 3 0

0

3 8 5 1

0

39.2 22.4

204 39.2 22.4 0 39.2 22.4 0 37.6 21.4

Process (1 to 14): De-inking Processes (1st stage) Process (15): Refining, chemical and miscellaneous processes (2nd stage) Process (16 to 21): Processes at Paper Machine (PM1 and PM2) (3rd stage)

2.2. Discretization of energy consumption, raw material and intermediate pulp products, and implementation of Discrete Event Simulation Firstly, waste papers are manually screened before being allowed to enter Drum Pulper. All the involved process to


transform paper waste into new paper roll are tabulated in sequence (Table 1) along with its process type, pulp weight at each processing station (per minute) and energy consumption rate (per minute). Recycling process starts at drum pulper processing and finishes at paper pope reeling station (last processing station at Paper Machine) which releases the paper master rolls. Some of the processes are performed as continuous running process. And some processes have definite processing time for a pulp batch size. These running machineries/equipment remain working continuously for 24 hours. To implement discrete event simulation for continuous cum discrete process scenario, raw material consumption, intermediate products and energy consumptions are quantized on per minute basis. So that, continuous and processing timebased processes can be simulated in same framework. Overall Energy Consumption in time ‘t’ = Electrical energy consumption + Steam energy consumption = (electrical energy used in processing + electrical energy used in stand-by power consumption + steam energy used in processing + steam energy used in stand-by power consumption) 𝑡𝑡

27

0

𝑖𝑖=1

𝑡𝑡

27

0

𝑖𝑖=1

= ∑ ∑(𝑛𝑛𝑖𝑖,𝑡𝑡 ∙ 𝐸𝐸𝐸𝐸𝐸𝐸𝑖𝑖 ) + ∑ ∑(𝑡𝑡 ∙ 𝑆𝑆𝑆𝑆𝑆𝑆𝑖𝑖 ) 𝑡𝑡

27

𝑡𝑡

27

0

𝑖𝑖=1

+ ∑ ∑(𝑛𝑛𝑖𝑖,𝑡𝑡 ∙ 𝑆𝑆𝑆𝑆𝑆𝑆𝑖𝑖 ) + ∑ ∑(𝑡𝑡 ∙ 𝑆𝑆𝑆𝑆𝑆𝑆𝑖𝑖 ) 0 𝑖𝑖=1

Production rate per minute =

(𝑛𝑛21,𝑡𝑡 ∙𝑚𝑚21 +𝑛𝑛27,𝑡𝑡 ∙𝑚𝑚27 ) 𝑡𝑡

3.1 Case study-1: Reference case (Ideal case of production flow) This case represents a production situation when plant is audited for seamless material flow (no buffering before any process and almost 100 percent time machines are engaged). This is an ideal situation of production flow. Some associated energy consumption issues are as follows. The De-inking processing stations (station1-station14) are utilizing 95% of its capacity. The processing station for Refining, Chemical & Miscellaneous processes is utilizing its 95% capacity as well. Paper Machine stations (station16station27) are utilizing 85% of their capacities only. Table 2. Electrical and steam energy contributions in machine stand-by and process execution consumptions for each individual processing station.

(1)

(2)

Total number of processing stations = zde-inking+ zrefining, chemical & miscellaneous + zPM1+ zPM2= 27 (3)

where, 1st to 14th stations are considered as zde-inking; 15th station is zrefining, chemical & miscellaneous; 16th to 21st stations are considered as zPM1; and 22nd to 27th stations are considered as zPM2. ni,t = number of discretized unit processed by ith processing station in time t SPEi= Stand-by energy consumption per minute by ith processing station through electrical energy source SPSi= Stand-by energy consumption per minute by ith processing station through steam energy source EEUi= Electrical energy consumption rate per discretized unit at ith processing station SEUi= Steam energy consumption rate per discretized unit at ith processing station mi=mass of discretized unit pulp produced at ith processing station, where i=1,2,3…..27. 3. Case studies Discrete event simulation experiments are carried out in Delmia Quest Software [9]. Simulations are carried out for two different case studies i.e., (1) Reference case (Ideal situation of production flow); (2) Working efficiency of two processing stations (First Stage Floatation station and

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Refining, Chemical & Miscellaneous processing station) reduce. Fig.1 is a snapshot of the discrete event simulation model developed using Delmia Quest Software. Here, each processing station is symbolized as a tank structure. It shows the material flow from entering location to the finished product collection point. Whereas, Fig.2 represents the process flow diagram and the quantity of pulp fiber transferred from station to station per day. It presents the projected mass flow and capacity estimates of each processing station, given by plant establishment team/engineers.

Processing station No.

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Processing Station Name

Drum pulper HD Cleaning station Coarse screening station Dump Tower LC Cleaning station 1st Stage floatation cell Thickening 1cell Dispersing station Bleaching Tower 2nd Stage floatation cell Thickening 2 station Bleaching Reactor processing station Storage Tower LC fine screening cell Refining, Chemical & and Miscellaneous processing station Approach Flow System –PM1 Wet end wire part -PM1 Wet end press part -PM1 Paper drying cell -PM1 Calendar cell-PM1 Pope reeling cell -PM1 Approach Flow System -PM2 Wet end wire part -PM2 Wet end press part -PM2 Paper drying cell -PM2 Calendar cell-PM2 Pope reeling cell -PM2

Energy consumption (MT/Minute) Stand- Stand- Electric Steam by by al in in electrica steam processi processi l ng ng 2.816 0.120 2.228 0.009 1.531 2.30 0.504 9.789 0.139 1.991 1.238

185.22 0 0 0 0 0 0 131.918 0 0 0

24.080 703.836 1.030 0 19.054 0 0.075 0 13.089 0 19.661 0 4.309 0 83.698 501.287 1.186 0 17.025 0 10.588 0

0

114.333

0

434.467

1.049 2.010

0 0

8.972 17.186

0 0

0.567

0

4.845

0

2.875 4.313 3.006 3.529 1.046 0.523 0.915 1.438 0.523 1.307 0.784 0.131

0 1.785 1.53 105.57 0 0 0 0 0 63.24 0 0

19.125 28.687 19.994 23.471 6.954 3.477 6.085 9.562 3.477 8.693 5.216 0.87

0 5.215 4.47 308.43 0 0 0 0 0 184.76 0 0

In electrical equipment/machineries, 10 percent electrical energy is used as stand-by power consumption. In steam

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energy equipment/machineries, 20 percent energy is used as stand-by power consumption (Table 2). Material transfer time between the processing stations is already considered during discretized pulp weight calculation (Table 1). In this case study, simulation results demonstrate that all the processing stations are showing almost 100 percent time machine engagement. In addition to that, results obtained in case study-1 simulation experiments are matching with the projected performance (production rate and energy consumption rate) of the plant in ideal running condition. As

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well as, material flow details obtained through simulation match with the practically flowing materials in real plant. Thus, it validates the proper functioning of the simulation model. The recorded results are as follows i.e., Paper production rate= 0.154217 Metric Ton/minute; Energy consumption per MT paper production = 18117.93 MJ/MT; Energy consumption rate= 2794.087 MJ/min. The reference case results are utilized as reference to compare further case study results.

Fig. 1. Snapshot of the simulation model showing the material flow direction(s) and 27 processing stations.

Legend: (Metric ton per day (mass of pulp fiber)/Pulp solution consistency (%)/Meter cube per day (pulp solution flow rate)) Fig. 2. Paper recycling process flow diagram showing De-inking, Refining, Paper machining and Finishing processes.

Keshari et al. / Procedia CIRP 00 (2018) 000–000 Anupam Keshari et al. / Procedia CIRP 78 (2018) 2–7

Scenario-1: 1st Stage Floatation station efficiency reduced by 20 percent Scenario-2: Refining, Chemical & Miscellaneous processing station efficiency reduced by 30 percent Scenario-3: scenario 1 and 2 happening together Scenario-4: along with low production situation of scenario 3, the Paper Machine 2 is kept off. Scenario-5: along with scenario 4, waste paper entering rate is reduced by 20 percent, and Paper Machine 1 capacity utilization is increased to 93 percent Scenario-6: along with scenario 4, waste paper entering rate is reduced by 28 percent, and Paper Machine 1 capacity utilization is increased to 93 percent. For all aforementioned scenarios, paper & pulp plant performances are evaluated by observing the overall energy consumption rate and paper production rate. Energy consumption rate in MJ/min and in MJ/MT are shown in Fig. 3 and Fig. 4 respectively. Whereas, paper production rate is summarized as split curve plot, shown in Fig. 5. These scenarios are nothing but the systematically changed facility/resource involvement that facilitates to analyze/compare effect of the changes in more comprehensive way. Moreover, performance comparison with the reference case brings out a useful justification of the presented results. The prime goal of these experiments is to search reasonable resource management options (reduction of input rate, keeping off some portion paper machine) to achieve optimum combination of energy efficiency and good production rate along with disturbance free production flow. Results obtained for the scenario-6 represent that high energy efficiency can be achieved along with very low flow disturbance by appropriate resource allocation.

Energy consumption rate (MJ/min)

This case study represents a usual situation of a working plant where working efficiency of some of the processing stations reduce occasionally by internal faults or by performance reduction of involved equipment and pumps. The case considers the efficiency reduction of First Stage Floatation station and Refining, Chemical & Miscellaneous processing station. Former is caused by physical deterioration of the involved pumps. Later one is often caused by internal faults resulting in sub optimal operation of involved components. To illustrate the effect of processing station’s working efficiency systematically, simulation experiments are carried out for six different production scenarios as below:

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energy consumption rate is to be scarified. Scenario 1

Scenario 2

Scenario 3

Scenario 4

Scenario 5

Scenario 6

3100 3000 2900 2800 2700 2600 2500 2400

0

100

200

300

400

500

600

700

Processing Time (min) Fig. 3. Energy consumption rate per minute obtained from all six scenarios.

Energy consumption rate (MJ/MT)

3.2 Case study-2: Working efficiency of two processing stations (First Stage Floatation station and Refining, Chemical & Miscellaneous processing station) reduce

Scenario 1 Scenario 4

23000



22000 21000 20000 19000 18000 17000 16000 15000

0

100

200

300

400

500

600

700

Processing Time (min) Fig. 4. Energy consumption rate per metric ton production obtained from all six scenarios. Scenario 1 Scenario 4



0.2 Production rate (MT/min)

6

0.18 0.16 0.14 0.12 0.1

0

100

200

300

400

500

600

700

Processing Time (min) Fig. 5. Production rate per minute obtained from all six scenarios.

4. Results and discussions As well as in scenario-3, production flow disturbance will The obtained results from all six scenarios are discussed having occur at two points. Wherein, high rate of buffering will be reference of the case study-1 results. In scenario-3 the found at First Stage Floatation station and at Refining, production rate is higher about 3.7% than scenario-6 (Fig.3), Chemical & Miscellaneous processing station. but to keep such increase in production rate, 12.5% more

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Anupam et CIRP al. / Procedia CIRP 78 (2018) 2–7 Keshari et al. Keshari / Procedia 00 (2018) 000–000

Minimum energy consumption per MT paper production is found in scenario-6, while smooth material flow is maintained throughout the flow except slight buffering at Refining, Chemical & Miscellaneous processing station. Thus, to cop up the loss of the energy and flow disturbance, the suggestion is made to reduce input rate by 28 percent and to turn off Paper Machine 2 along with the 8 percent increase of capacity utilization of Paper Machine 1. Moreover, it is suggested to imply strict process management over Refining, Chemical & Miscellaneous processing station to improve efficiency by 5 percent at least, in next coming days. So that, the occurred disturbance in material flow can also be avoided easily. If, the plant resource is managed according to the suggestion, 439016 MJ energy can be saved per day.

change of energy source option and change in input rate of multiple raw materials will frame energy efficient production strategy without significant loss of production rate and disturbance in material flow. Acknowledgements The authors would like to thanks Nepa Ltd., Nepanagar, Burhanpur, Madhya Pradesh, India for supporting this research by enabling basic understanding of paper and pulp industry resources, processes and concerned energy issues. References [1]

5. Conclusions The integrated pulp and paper (P&P) industry is one of the examples of the process industry wherein some processes are executed as continuous running process, and some have definite processing time. Herein, resource consumption variation comes through many ways i.e., raw material diversity, change in paper quality, variation in raw material input rate, plant and machinery break-downs, efficiency reduction of the processing units etc. In such industries, resource management is very complicated task to establish disturbance free seamless material flow throughout the plant and to search energy efficient resource options. The research presents an implementation of discrete-event simulation for such complex problem scenario, wherein discretized form of energy consumptions, weight of the pulp at the start, end and intermediate stages are used. All quantization is done on per minute basis. Case study of a real time working pulp and paper industry is presented. Discrete-event simulation experiments are carried out for two different case studies. Case study-1 represents an ideal situation of production flow and energy consumption rate similar to the projected situation (free from any faults, depreciation and flow disturbance) stated by energy audit experts. Case study-2 represents the situation wherein working efficiency of two processing stations (first stage floatation station and Refining, chemical and miscellaneous processing station) reduce. Case study-2 also searches the energy efficient resource management options by changing the experimental scenarios. By implementing the scenario-6, effect of deficiency of processing stations can be minimized, and best possible energy efficacy can be achieved. Thus, the presented approach of discretized definitions and implementation with discrete event simulation can be a reliable & viable technique to analyze energy consumption and flow of pulp throughout the plant, and to search energy efficient resource management options. The approach demonstrates good potential to be implemented over any integrated process industry problems. In future, the approach will be extended to multiple raw material input with multiple energy alternative problems of Paper & Pulp plant. The

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[2] [3]

[4]

[5] [6] [7] [8] [9]

[10]

[11] [12]

[13]

Schumacher K, and Sathaye J. India’s pulp and paper industry: Productivity and energy efficiency. LBNL-41843, Lawrence Berkeley National Laboratory; 1999. Comodi G, Cioccolanti L, Pelagalli L, Renzi M, Vagni S, & Caresana F. A survey of cogeneration in the Italian pulp and paper sector. Applied Thermal Engineering 2013; 54(1): 336-344. Schulze, M, Nehler, H, Ottosson, M, & Thollander, P. Energy management in industry-a systematic review of previous findings and an integrative conceptual framework. Journal of Cleaner Production 2016; 112: 3692-3708. Kramer KJ, Masanet E, Xu T, & Worrell E. Energy efficiency improvement and cost saving opportunities for the pulp and paper industry. An ENERGY STAR® guide for energy and plant managers. LBNL-2268E. Lawrence Berkeley National Laboratory; 2009. Laurijssen J, Faaij A, & Worrell E. Benchmarking energy use in the paper industry: a benchmarking study on process unit level. Energy efficiency 2013; 6(1):49-63. Sivill L, & Ahtila P. Paper Machine production efficiency as a key performance indicator of energy efficiency. Chemical Engineering Transactions 2009; 18: 905-910. Moshkelani M, Marinova M, Perrier M, & Paris J. The forest biorefinery and its implementation in the pulp and paper industry: Energy overview. Applied Thermal Engineering 2013; 50(2):1427-1436. Suk S, Liu X, & Sudo K. A survey study of energy saving activities of industrial companies in the Republic of Korea. Journal of Cleaner Production 2013; 41: 301-311. Caggiano A, Keshari A, Teti R. Analysis and Reconfiguration of a Manufacturing Cell through Discrete Event Simulation, 2nd IPROMS International Researchers Symposium, Ischia, July 22-24, 2009, ISBN 978-88-95028-38-5: 175-180. Posch, A, Brudermann, T, Braschel, N, & Gabriel, M. Strategic energy management in energy-intensive enterprises: a quantitative analysis of relevant factors in the Austrian paper and pulp industry. Journal of Cleaner Production 2015; 90: 291-299. Jovanović, B, Filipović, J, & Bakić, V. Energy management system implementation in Serbian manufacturing–Plan-Do-Check-Act cycle approach. Journal of Cleaner Production 2017; 162: 1144-1156. Trianni, A, Cagno, E, Marchesani, F, & Spallina, G. Classification of drivers for industrial energy efficiency and their effect on the barriers affecting the investment decision-making process. Energy Efficiency 2017; 10(1): 199-215. Sonsale AN, Keshari A, Pohekar SD. Scope and Methods for Establishing Energy Efficient Paper & Pulp Industry, DST sponsored National Conference on “Renewable Energy and Energy Conservation”, May 20-21, Poornima University, Jaipur, India; 2016.