Available online at ScienceDirect. Energy Procedia 56 (2014 )

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1 Available online at ScienceDirect Energy Procedia 56 ( t Eco-Energy and Materials Science and Engineering (11t EMSES Perormance o steam production by biomass combustor or Agro-industry B. Prasit a and P, Maneecot a a Department o Scool o Renewable Energy Tecnology (SERT, Naresuan University, Pitsanulok 65000, Tailand. Abstract Tis researc paper aims to particularly raise te issue ow optimization o steam production produced by a biomass combustor is regarded to agricultural industry, or te produced steam will consequently be applied to sterilization or even drying process. Te most optimal level o steam production will be explored as to ow to optimally acieve low rate o air, rate o uel input, te rate o steam production, and steam production in compliance wit te given 100 kg/ capacity and te required temperature o between O C. Biomass steam production incorporates 3 major parts: 1 biomass combustor, eat excanger system (coiled tube, and 3 control system, administered te wole process, located at te Scool o Renewable Energy Tecnology, Naresuan University, Pitsanulok. A combustion system was tested troug te implementation o eucalyptus carcoal as te main source o energy. Te researc inding revealed tat te combustion system could generate steam at 100 kg/ wic consumed eucalyptus carcoal at te temperature value o Heating value o uel (HHV was 30.0 MJ/kg. Tis was conducted witin te biomass combustor, engaged wit a coil tube, at te low rate o 17.8 kg/, te value o eed rate o uel at 15 kg/, and a steam production rate at 100 kg/ respectively. Te eiciency o steam production was at 58.5 %. Wen te taken result was brougt to compare wit a matematical model wit experiment result o steam production, it was ound out tat te error value was wic could useully be used to predict steam production in te system. Wit reerence to te economical beneit, wen compared to steam production produced by LPG uel at 100 kg/ production rate, it was obvious tat steam production generated by biomass could redeem te spent investing cost wit less tan one year. Tis would greatly be interesting and applicable to industry particularly agriculture tat steam production by biomass combustor wit elical coiled boiler tecnique will be used to energy backup or drying system. However steam production will be supported drying system ater utilization in anoter termal process te temperature not more tan 100 O C witin industrial or industrial ouse old. Keywords: Steam Production, Biomass Combustor, Helical coiled boiler tecnique Publised by Elsevier Ltd. Tis is an open access article under te CC BY-NC-ND license (ttp://creativecommons.org/licenses/by-nc-nd/3.0/. Peer-review under responsibility o COE o Sustainalble Energy System, Rajamangala University o Tecnology Tanyaburi (RMUTT doi: /j.egypro

2 B. Prasit and P. Maneecot / Energy Procedia 56 ( Introduction Furter to te energy crisis in te world wic inevitably aects bot entrepreneurs and consumers, renewable energy as ten been raised to an issue as an clean energy alternation. In Tailand, renewable energy is increasingly playing its signiicant role to correspond wit a number o renewable energy policies, wic, at present, te energy is consumed at 8 %. Te current consumed rate is divided into electricity (1%, termal power (.5%, and uel power (.5%[1]. For termal power, tis is vital to te agricultural processing industry wic requires a massive amount o termal power or sterilization, drying, etc. Tis ranges rom small, medium, and large business, including agricultural group in Tailand. Steam production could yield tremendous termal power or applying wit processing process or sterilized process wic demands a temperature o iger tan 100 O C. However, present steam production as wasted a large number o non-renewable and ig-demanding energy suc as oil, LPG, and electricity wic are considered dear and environmental non-riendly. I letover material, in tis case is biomass, could be implemented as a source o energy in eiter orm o solid or carcoal, it will greatly reduce a number o waste material and environmental pollution at te actory level and te community level. Biomass sould, owever, be judiciously used, or it could create diiculties in delivering a proper management. Besides, a proportion o uel, a proper air low rate or combustion, and a smoot liquid low are required to be careully monitored ence a wellcontrolled steam production. Sould te said issues are not met appropriately, te uel consumption, te low rate o air, and te steam production rate will not be optimally acieved. Te well-controlled steam production results in a more predictable output o steam and tat agriculture groups and industries could earn a vast beneit and advantage rom tis application. Fig. 1. Steam production system by biomass combustor

3 300 B. Prasit and P. Maneecot / Energy Procedia 56 ( Tis researc paper discusses te study o steam production tecnology by a biomass combustor engaged wit te elical coiled tube wic unctions as a eat excanger to eat up water until te steam is acquired at te 100 O C. Material used to incinerate in te biomass combustor is eucalyptus carcoal, and liquid matter lown in system is water. Te elical coiled tube located inside te combustor will excange eat and dissipate te eat to te water witin te coil tube until te 100 O C Celsius is reaced; tis metod is arguably better tan eating water in te straigt pipe at te same given space. It is important tat te proper collective eat and economical eiciency o te biomass combustor or agricultural purposes be ound out. Tis will, as a result, elp entrepreneurs reduce incurred expenses in terms o energy costs and supersede non-renewable energy wit biomass wic could eectively yield a great deal o termal power. It will also elp entrepreneurs considerably decide to coose te steam production tecnology using biomass wic apparently resolves te rate o breakeven point in business compared to te steam production produced by ossil uel.. Materials and review o related literature review.1 Biomass Biomass is a term or all organic materials tat stems rom plants (including algae, trees and crops. Biomass is produced by green plants converting sunligt into plant material troug potosyntesis and includes all land- and water-based vegetation, as well as organic waste. Te biomass resource can be considered as organic matter, in wic te energy o sunligt is stored in cemical bonds. Wen te bonds among adjacent carbon, ydrogen and oxygen molecules are broken by digestion, combustion, or decomposition, tese substance release teir stored, cemical energy. Biomass as always been a major source o energy or mankind and is presently estimated to contribute about 10-1% o te world energy supply []. Due to increase in uel costs and concerning environmental impact, te utilization o biomass or ossil uel substitution as drawn attention rom people concerned in many aspects, particularly in global warming issue. Crucial reduction o carbon dioxide emission approximately accounts or 75% o green ouse gases is one o te main reasons. However biomass will be used or steam production tat ave studied and take it or clean energy wic reduce environmental problem. Development o steam production Worldwide : C. Franco, F. Pinto, I. Gulyurtlu, I. Cabrita. [3] te study o reactions inluencing te biomass steam gasiication process. Steam gasiication studies were carried out in an atmosperic luidised bed. Te gasiier was operated over a temperature range o O C. Tree types o orestry biomass were studied: Pinus pinaster (sotwood, Eucalyptus globulus and olm-oak (ardwood. wic A.M. Abdalla, A.L. Ismail. [] to study saving energy lost rom steam boiler vessels. Tis study is concerned wit two important and inter-related issues: te issue o energy conservation and te issue o environment protection. And T.M.I. Malia, M.Z. Abdulmuin, T.M.I. Alamsya, D. Muklisien. [5] learning dynamic modeling and simulation o a palm wastes boiler. A state-space dynamic model or a palm wastes boiler is being developed and simulated. Te unique eature o tis boiler is tat it uses wastes in te orm o iber and sell rom te palm oil processing as its uels. However development o steam production in Tailand: Ratiya Tuvapanitcyanun, Somcart and Somkiat Pracayawarakorn. [6] to study te matematical model or luidized bed drying using supereated steam. Matematical model or luidized bed drying wit supereated steam was developed to predict drying rate in soybean. Ubonwan Campai. Somcart Soponronnarit and Somkiat Pracayawarakorn. [7] to study matematical modeling or a single soybean drying wit supereated steam and ot air. Development o steam production in Scool o Renewable Energy Tecnology (SERT : Naresuan University, Pitsanulok, Tailand. Anan Pongtonkulpanic, Sukruedee Natakaranakule, Bongkot Prasit and Saataya Ladpala. [8] ig pressure steam production by solar termal integrated wit biomass energy or power generation o community. Tis paper describes researc into renewable energy tecnology or electricity production to be used in te communities o Tailand. However, Sarayoot Vaivud. Nimit Sriprang. Nipon Ketjoy and Wattanapong Rakwician. [9] researc about system design o ig termal energy storage or solar termal power plant. Helical coiled pipe eat excanger discarging experimental results sowed te igest storage eiciency o Conclusion; biomass energy is produces eat energy rom agricultural residues. However, biomass will be used as uel because o ater agricultural processing will be a lot o biomass as waste and unutilization or termal energy processing wic is environment problem in te industry. I we can take it to produce termal energy or steam

4 B. Prasit and P. Maneecot / Energy Procedia 56 ( production tat will be acieved and spring up to utilize in agro-industry or community, it can save cost o uel, investment and reduce environmental problem. Tis researc would like to conduct te optimization and payback period analysis o steam production by biomass combustor or agro-industrial application. Working operates o te system tat biomass completed combustion can be produce steam production system. Tis system is continuously produces steam at all time wic saves cost and saves energy consumption tat replaces te conventional energy or ossil uel... Researc instrument and metods Researc instrument Steam production system by biomass combustor Te diagram o steam production system by biomass combustor is sown in te ollowing igure. Te system was developed or steam production consists o 3 main parts: 1. Biomass combustor. Helical coil tube 3. System control Furnace. System control 3. Water tank. Water pump 5. Blower 6. Cyclone 7. Transmitting belt 8. Pressure and temperature instrument 9. Helical coil tube Fig.. Steam production system by biomass combustor

5 30 B. Prasit and P. Maneecot / Energy Procedia 56 ( Metodology Metodology Heat transer rate o elical coiled tube in biomass combustor [10] Scale on te water side o elical coiled tubes Tis is anoter problem tat can be considered using conduction teory. I te tube are initially clean and ree rom scale te eat transer rate is : = (k w /da(t g - t w (1 Ater operation over a period o time, scale may develop and build up as sown scematically. Te eat transer ten is : = (k w /d A (t g - t i ( = (k s /d s A (t i t w Were k w = termal conductivity o clean tube, W/mK k s = termal conductivity o scale, W/mK d = tickness o tube, m d s = tickness o scale, m A = area o eat transer, m t g = combustion gas temperature, O C t w = water temperature, O C t i = te scale/tube interace temperature, O C Boiler eiciency Boiler eiciency is expressed as a percentage and is calculated by dividing te output o te boiler by in put to te boiler. [11] boiler ms ( m HHV (3 Were m s = Steam Flow, kg/ m = Fuel low, kg/ HHV = Heating value o uel, MJ/kg = Heat content o steam, kj/kg = Heat content o eed water, kj/kg Te required eat transer rate may be obtained rom te overall energy balance or te cold luid [1] q Cc ( Tc, o Tc, i ( mc p c ( Tc, o Tc, i ( Combustion Stoiciometry is about te mass balance in te reaction o combustion tat will be elped to calculate te volume o oxidation or air wic Necessary to ave complete combustion; CHONS-uel air equation can be sowed on below. C U H V O W N S v uco H O yso X Y v w u y ( O 3.76N v w x 3.76u y N (5

6 B. Prasit and P. Maneecot / Energy Procedia 56 ( In term o w to sow oxygen in uel or combustion and u, v, w, x and y is mole o element C, H, O, N and S respectively wic is ingredient in 1 kg o mass uel. [13] Start Stoiciometry o Biomass, input u,v,w,x,y v w CU H V OW N X SY u y( O 3.76N v uco H O yso v w x 3.76u y N Mass low rate o air m ( A/ F STOICH kg / kgxm kg / s Input m, m, HHV,, 676.1kJ / kg; TSATVAPOR 100 C S Calculated ; boiler m ( ( m HHV S y mx boiler Input m, HHV, m ( ( m HHV S boiler boiler Cal ms(- Cal ms(- Mat Testing Compared R > 0.99 R < 0.99 No Yes X m m g t vav v v g End Fig. 3. Metodology or steam production by biomass combustor optimization

7 30 B. Prasit and P. Maneecot / Energy Procedia 56 ( Results and discussion Tis researc can produce steam or Agro- industrial suc as sterilization or drying tat temperature about O C, It is steam production or supporting termal energy system or Agro-industrial. Te steam production by biomass combustor system consists o tree parts: 1 biomass combustor steam tube 3 control system. Tis system is installed at te Scool o Renewable Energy Tecnology (SERT, Naresuan University, Pitsanulok, eucalyptus carcoal will be used as biomass uel in biomass combustor. Table 1. Te properties o eucalyptus carcoal Proximate Analysis Ultimate Analysis Description Weigt % Description Weigt % Moisture 8.96 Carbon 98.9 Volatile Matter 16.1 Hydrogen 0.80 Fixed Carbon Oxygen 0.0 As 3.3 Nitrogen 0.87 Caloriic 9.57 Sulpur 0.0 Value,MJ/kg Calculation o Combustion Stoiciometry Combustion Stoiciometry is about te mass balance in te reaction o combustion tat will be elped to calculate te volume o oxidation or air wic Necessary to ave complete combustion; CHONS-uel air equation can be sowed on equation (5. In term o w to sow oxygen in uel or combustion and u, v, w, x and y is mole o element C, H, O, N and S respectively wic is ingredient in 1 kg o mass uel. Combustion Stoiciometry o mass uel 1 kg by Equation (5. Tat used Eucalyptus carcoal or combustion. Combustion Stoiciometry calculation (A/F stoic was 11.5 by mass uel tat can be ined velocity o air wic velocity o air was. m/s tat will be supported te steam production system used biomass uel 10 kg/day wic te system operating was 10 our/day. In te eat transer analysis o eat excangers, various termal resistances in te pat o eat low rom te ot to te cold luid are combined into an overall eat transer coeicient U. By neglecting te tube wall resistance to eat low and te curvature eect (i.e., assume D o D i tat te overall eat transer coeicient becomes 50.8 W/m. O C and Te eat loss per meter lengt o tube is W/m wen it Calculation in orm elical coil tube wic te eat loss per meter lengt o tube is W/m. Te optimum point o steam production at eiciency equal 58.5% and R = rom testing linear regression can predict te mass low rate o steam production wen we were input mass low rate o uel (m, ig eating value (HHV, entalpy o water, entalpy o steam. Te process can prediction anoter material tat is biomass. Heat transer rate equal.93 MW/m and te quality o steam about 0.58.

8 B. Prasit and P. Maneecot / Energy Procedia 56 ( Fig.. Linear regressions te eiciency o steam production Fig. 5. Comparison matematical model wit experiment result Te result o testing te water temperature inlet (T c,i was 30 O C, te water temperature outlet (T c,o was 100 O C and te weigt o water about 1.0 kg can be sowed q = kj. Te Matematical model can be calculated te optimum point rom testing and can predict te result rom testing and matematical model at R = tat is accuracy and used or steam production. Economic analysis in tis researc as compared te steam production system by biomass combustor wit LPG boiler. Te economic analysis o te system and ind out pay back period in case ; replace te operating LPG boiler system to steam production by biomass combustor tat eucalyptus carcoal will be used as biomass uel in biomass combustor.

9 306 B. Prasit and P. Maneecot / Energy Procedia 56 ( Assumption and parameters or evaluation economic analysis consist o ; Capital cost o building te system - Biomass steam production system 150,000 Bat - LPG Boiler 300,000 Bat Te cost o uel or steam production - Biomass uel 0. Bat/kg - LPG 0 Bat/kg Discount rate 7.5% Total our o operating system 1080 our/year Maintenance cost 6% o te system Te cost o electricity.5 Bat/kW Ruins value o te system 10% o capital cost o building te system In team o payback period analysis te reward net per year will be compared te cost o uel, maintenance cost electricity cost and as revenue Te capacity o steam production 100 kg/ Payback period, PB o biomass steam production system was 0.9 year wen compared wit LPG boiler. Considering annual costs per steam production rate, (Bat, C TS and operating cost per steam production rate, (Bat, C MS te result o tis researc sowed : Biomass steam production was Bat/ton and Bat/ton tat LPG boiler system was 363. Bat/ton and 17.7 Bat/ton respectively. Te economic analysis o biomass steam production system as sot time payback period because o te parameters suc as uel cost, electricity cost, capital cost and as revenue were lower tan tose or LPG boiler system. For tis reason te biomass steam production system will be used or agro-industrial application more tan LPG boiler at te present. To study te eat transer o steam witin copper tube tat eat transer to solar tunnel dryer wic study to easibility o termal conductivities rom gasiier combined wit solar tunnel dryer Fig. 6. Heat excanger (Copper tube witin solar tunnel dryer Fig. 7. Solar tunnel dryer tecnology

10 B. Prasit and P. Maneecot / Energy Procedia 56 ( Steam production system or solar tunnel dryer in term uel cost o operating system between LPG boiler wit biomass combustor or steam production wic consideration in term uel cost per year o operating: Te uel cost o LPG boiler and biomass combustor or steam production tat are dierent. Te biomass combustor or steam production system can be save uel cost 50,000 Bat/year. Q Q Q A( T T A( T conv rad T s (6 Were Q L = ( DL( T T ( DL( T ( D( T T ( D( T T T = Convection eat transer coeicient L = Heat loss per meter lengt o tube, m = Temperature o surace area o copper tube, O C T =Air temperature witin tunnel dryer, O C T s = Temperature o tunnel dryer, O C =Emissivity = Stean-Boltzmann, 5.67 x 10-8 W/m K T s s Te energy production witin tunnel dryer was W/m. Te system will be tested te perormance o solar collector and temperature distribution witin tunnel dryer combined termal energy rom biomass. Te copper tube is eat excanger tat water temperature about O C passing to te tunnel dryer wic eat up te temperature O C witin te system. Te solar dryers can dry agricultural product in te several temperature level wic is suitable to disseminate or armers and general person wo would like to transorm agricultural product or reduce conventional energy like; natural gas oil and electricity.. Conclusion Te most optimal level o steam production will be explored as to ow to optimally acieve low rate o air, rate o uel input, te rate o steam production, and steam production in compliance wit te given 100 kg/ capacity and te required temperature o between O C. A combustion system was tested troug te implementation o eucalyptus carcoal as te main source o energy. Te researc inding revealed tat te combustion system could generate steam at 100 kg/ wic consumed eucalyptus carcoal at te temperature value o Heating value o uel (HHV was 30.0 MJ/kg. Tis was conducted witin te biomass combustor, engaged wit a coil tube, at te low rate o 17.8 kg/, te value o eed rate o uel at 15 kg/, and a steam production rate at 100 kg/ respectively. Te eiciency o steam production was at 58.5 %. Wen te taken result was brougt to compare wit a matematical model o steam production, it was ound out tat te error value was wic could useully be used to predict steam production in te system. Wit reerence to te economical beneit, wen compared to steam production produced by LPG uel at 100 kg/ production rate, it was obvious tat steam production generated by biomass could redeem te spent investing cost wit less tan one year. Te copper tube is eat excanger tat water temperature about O C passing to te tunnel dryer wic eat up te temperature O C witin te system. Tis would greatly be interesting and applicable to industry particularly agriculture. Acknowledgements Te autors are grateul to Scool o Renewable Energy Tecnology, Naresuan University, Pitsanulok Tailand. supported te laboratory experiments or testing. Reerences [1] EPPO. Strategic Plan ; 003. [] McKendry, Peter. 00. Energy production rom Biomass (part1: overview o biomass. Bioresource Tecnology, 83(1, 37-6.

11 308 B. Prasit and P. Maneecot / Energy Procedia 56 ( [3] C. Franco, F. Pinto, I. Gulyurtlu, & I. Cabrita. (003. Te study o reactions inluencing te biomass steam gasiication process. Sciencedirect o Fuel. 8, [] A.M. Abdalla, & A.L. Ismail. (001. Saving energy lost rom steam boiler vessels. Renewable Energy. 3, [5] T.M.I. Malia, M.Z. Abdulmuin, T.M.I. Alamsya, & D. Muklisien. (003. Dynamic modeling and simulation o a palm wastes boiler. Renewable Energy. 8, [6] Ratiya Tuvapanitcyanun, Somcart Soponronnarit and Somkiat Pracayawarakorn. (00. Matematical model or luidized bed drying using supereated steam. Bangkok: King Mongkut s University o Tecnology Tonburi. [7] Ubonwan Campai. Somcart Soponronnarit and Somkiat Pracayawarakorn. (005. Matematical modeling or a single soybean drying wit supereated steam and ot air. Bangkok: King Mongkut s University o Tecnology Tonburi. [8] Anan Pongtonkulpanic, Sukruedee Natakaranakule, Bongkot Prasit and Saataya Ladpala. (006. Hig pressure steam production by solar termal integrated wit biomass energy or power generation o community. Pitsanuloke: Naresuan University. [9] Sarayoot Vaivud. Nimit Sriprang. Nipon Ketjoy and Wattanapong Rakwician. (006. System design o ig termal energy storage or solar termal power plant. Pitsanuloke: Naresuan University. [10] J R Cornort, BSc, CEng, MIMecE, FlnstE. FlGasE Combustion Engineering and Gas Utilisation. Typeset and printed in Great Britain by Te College o Fuel Tecnology, London. [11] Everett B. Woodru, Herbert B. Lammers and Tomas F. Lammers Steam Plant Operation. McGraw-Hill book company. New York. [1] Rames K. Sa and Dusan P. Sekulic Fundamentals eat excanger design. Jon wiley & Sons, INC. New Jersey ; Cannada. [13] Sumruang Jakjai. Combustion. Typeset and printed in Culalongkorn University. Tailand.