EFFECTS OF FOSSIL DIESEL AND BIODIESEL BLENDS ON THE PERFORMANCES AND EMISSIONS OF AGRICULTURAL TRACTOR ENGINES

Transcription

1 EFFECTS OF FOSSIL DIESEL AND BIODIESEL BLENDS ON THE PERFORMANCES AND EMISSIONS OF AGRICULTURAL TRACTOR ENGINES y Miln D. TOMIĆ *, Lzr Đ. SAVIN*, Roslv D. MIĆIĆ**, Mirko Đ. SIMIKIĆ*, Timofej F. FURMAN* *Deprtment of Agriulturl Engineering, Fulty of Agriulture, University of Novi S, 21 Novi S, Seri **Petroleum inustry of Seri, 21 Novi S, Seri Rpi growth in the energy onsumption hs onitione the nee for isovering the lterntive energy resoures whih woul e pte to the existing engine onstrutions n whih woul stisfy the itionl riteri relte to the renewility, eology n reliility of use. Introution of ioiesel hs een the fous of ttention over the lst ten yers. The im of this reserh is to investigte the influene of ioiesel on the performnes n exhust gs emissions of meium power griulturl trtor engines (37-66 kw). The reson for the seletion of this tegory is tht those types of trtors re most frequently use in griulture. In this reserh ioiesel proue from sunflower oil ws lene with fossil iesel. Bioiesel, fossil iesel n fossil iesel lens with 15, 25, 5 n 75%v/v ioiesel were teste for their influene on the engine performnes n emissions. The testing ws performe on four-yliner iesel engine with 48 kw rte power. The experimentl reserh on the engine performnes ws onute in ompline with OECD test CODE 2, n the exhust gs emissions were teste oring to the ISO , C1. The use of ioiesel n fossil iesel lens reue the engine power with the inrese of ioiesel shre in the len. However, the exeption ws the len with 15%v/v ioiesel whih inue slight inrese in the engine power. Depening on the shre of ioiesel in the len ll lens fuels showe inrese speifi fuel onsumption ompre to the fossil iesel. Therml effiieny inrese s result of more omplete omustion of ioiesel n fossil iesel lens. The exhust gs emissions implie tht the ition of ioiesel reue the ontent of CO 2 n CO, s well s the temperture of exhust gses, ut it inrese the emission of NOx. Key wors: Bioiesel, iesel, trtor, performne, emissions 1. Introution Energy onsumption is onstntly inresing ll over the worl in spite of the rtionliztion mesures tht hve een unertken. Energy use in the trffi hs inrese y 16.42% over the lst ten yers rehing the level of kt of oil equivlent [1]. Liqui fossil fuels re the min n most frequently use fuels for moile mhinery. This refers not only to the si mens of trnsporttion, ut lso to wie rnge of mhinery use in the onstrution usiness, inustry, * Corresponing uthor: Fulty of Agriulture, Trg Dositej Orovi 8, 21 Novi S, Seri, e-mil: milnto@polj.uns..rs, 1

2 griulture... Consiering the ft tht the entire evelopment of moile mhinery is se on the use of liqui fossil fuel, it is ompletely unrelisti to expet shift from this tren to mss evelopment n use of new engine onstrutions tht woul e suitle for some other type of fuel. Therefore, the stuies hve een fouse on isovering the fuel tht woul e ptle to the existing engine onstrutions n tht woul meet the riteri regring renewility, eology n reliility of use. Fulfillment of the mentione riteri is the sis for suessful fossil fuel replement y some other types of fuel. During the lst ee ioiesel hs eome the most ommon renewle liqui fuel ue to its possiility to meet the set requirements of the previously mentione riteri. Nmely, the use of ioiesel oes not require ny type of engine moifitions or moifitions of the fuel injetion system. The exeptions re oler engine onstrutions whih nee replement of selnt n fuel injetion hose [2]. In its omposition ioiesel is ftty i methyl ester. It is proue from vegetle oils or niml fts [3] whih give ioiesel the renewility feture. The thir eologyrelte riterion gives ioiesel the gretest vntge over fossil iesel. It is well known tht fossil iesel onsists of hunres of ifferent rohyrte hins with sulfur resiue n remining rue oil. Also, even the low sulfur n low romti fossil iesel fuels ontin 2-24% of romtis (enzene, toluene, xylene, et.) whih re voltile, toxi n nerogeni [4]. On the other hn, ioiesel oes not ontin sulfur or romti ompouns. It reues the possiility of engine wer euse ioiesel is hrterize y goo luriting properties when ompre to fossil iesel n low sulfur iesel fuels [5]. This is how the fourth riterion is met (the reliility of use). Bse on the experiene from ioiesel use, the performnes of engine (power, torque n fuel onsumption) using ioiesel re similr to the engine performnes provie y fossil iesel omustion [6]. The emissions of HC, CO [7] n prtiulte mtter (PM) re reue with ioiesel use. The CO emission is lowere y 3-5%, epening on the shre of ioiesel in the len. This is minly ue to the higher ontent of oxygen n lower hyrogen n ron ontent [8]. Some uthors hve isovere tht the emission of CO 2 ours in the omustion proess of ioiesel within the limits from 2 to 25% of totl fossil iesel omustion [9]. As oppose to them, other uthors provie the results oring to whih there is no signifint ifferene in the CO 2 emission [1]. Nevertheless, esies the stte vntges, the use of ioiesel poses some prolems s well. Aoring to the previous stuies, the use of ioiesel inreses the ontent of NOx in the omustion prouts [7,11]. Higher NOx ontent in the omustion prouts n e expline y high oxygen ontent in ioiesel [12]. Sine the reue NOx ontent represents n importnt prmeter in the introution of EURO 3 n 4 norms on the exhust gs emissions, pplition of evies for further exhust gs tretment is neessry [11, 13]. Unfvorle low temperture hrteristis of ioiesel rise the prolems of engine strt n use of iesel engines in ol wether [14]. Another isvntge of ioiesel use lies in high hygrosopy euse ioiesel sors wter uring storge [15]. Oxition stility is one of the iggest prolems relte to the use of ioiesel. The Rnimt test (ISO 6886), opte within the stnr EN for oxition stility, regultes the miniml inution perio of 6 hours [16]. Still, meeting suh limit is iffiult in prtie unless ntioxints re e. Aoring to the onute reserhes the strong teneny towrs the oxition is onsequene of multiple oule ons present in one hin of ftty is [17] whih is why the use of oil with high ontent of linolei n linoleni i oul represent the prolem for ioiesel use. 2

3 Another prolem relte to the ioiesel use is its prie onitione primrily y the prie of the rw mteril [18]. Bioiesel is proue from ifferent plnts (soyen, sunflower, oil see rpe, plm, lge) n rw mteril otine from nimls (niml ft), ut it n lso e proue from wste oil n grese. The use of griulturl rops (sunflower, soyen, oil see rpe) is espeilly importnt for frmers euse these rops re in the sowing struture so the frmers re fmilir with the tehnology of their proution. Aprt from tht, y-prouts (oil ke) n e use s niml fee, whih reues the ioiesel prie y out 2-25 %. Also, vloriztion of glyerol n reue the ioiesel prie y 2.1%. Furthermore, with pproprite hoie of tlyztor (KOH) n is for neutrliztion, slts from ioiesel neutrliztion n e qulittively vlorize s prout for griulture. This primrily refers to the proution of high qulity potssium folir mnures (fertilizers) for rops. One ton of ioiesel gives out 15-2 kg potssium sulphte (K 2 SO 4 ) [19]. Another y-prout in the oilsee rpe proution is 4.4 t/h of plnt mss with lorifi vlue of 17.4 kj/kg [2]. From the eonomi spet, vloriztion of the ove mentione y-prouts n mke ioesel prie ompetitive with respet to fossil iesel fuel. Previous reserh inite tht ioiesel proution is multiisiplinry prolem n tht it is not only importnt for energetis n eology [21]. One of the more importnt spet of introution of ioiesel is the inrese in the employment rte. Nmely, oring to the Ntionl Bioiesel Bor report it is expete tht in 212 ioiesel proution will provie jos for 78. people in the USA, n tht 1 million of ioiesel litrs will inrese the GDP y out 386 illion [22]. The importne of ioiesel is lso evient in rurl evelopment. Creful plnning of proution pities woul tute rurl evelopment n erese the migrtion of people into ities. Over the pst few yers numerous stuies hve pulishe the results of omprtive engine tests for fossil iesel, ioiesel n their lens. Interestingly, lmost ll the tests hve een performe for either low power engines with the power of up to 5 kw, or the high power engines tht hve more thn 1 kw power. On the other hn, only few tests hve een performe for meium power engines (37-66 kw) whih re most ommonly use in griulture y trtors tht perform numerous grotehnil opertions. Out of totl numer of two-xle trtors use in the Repuli of Seri (35,) 56.12% flls into this tegory [23]. These trtors mke 67% in the totl fuel onsumption y griulturl mhinery. Thus, the im of this reserh is to give n ojetive evlution of the effets of use of ioiesel n fossil iesel lens on the performnes n exhust gs emissions of meium power trtors. In the Repuli of Seri ioiesel n e proue from sunflower whih is the most ommon oilsee rop. The ln re of h is overe with sunflower prouing the verge yiel of 2.9 t/h [24]. Fvorle limti onitions, long trition, mstere proution tehnology n lrge numer of omestilly proue hyris re ll vntges for the sunflower proution. Other vntges of sunflower re high energy vlue of sunflower ke n goo soures of protein with mino i vililities similr to those of soyen mel. Also, sunflower mel oes not hve nti-nutritionl ftors suh s those foun in soyen n rpesee mels [25]. 2. Mterils n methos 2.1. Fuels 3

4 Bioiesel lening ws rrie out in the following rtios uring the nlysis: 85:15%(v/v) fossil iesel : methyl ester (BD-15), 75:25%(v/v) (BD-25), 5:5%(v/v) (BD-5), 25:75%(v/v) (BD- 75) n :1% (BD-1). The results were ompre with the ommeril fossil iesel. Methyl ester (ioiesel) ws otine y the proess of trnsesterifition of sunflower oil in methyl lohol in the presene of NOH tht ws use s tlyst. Domesti sunflower hyri Somor ws use in the reserh. It is meium lte hyri whih mtures in the perio of ys. The geneti potentil for see yiel is 4.6 t/h. Oil ontent in the see is 48-51%. Prior to the tests, the nlysis of ioiesel ompline with the stnr EN ws performe. Results of the nlysis inite tht the use ioiesel is in line with EN stnr (Tle 1). Tle 1. Properties of use ioiesel (SRPS EN 14214:29) Property Units Limit Vlue Metho Ester ontent % (m/m) Min EN 1413 Density t 1 o C kg/m EN ISO 3675 Kinemti visosity t 4 o C mm 2 /s EN ISO 314 Flsh point (Penskiy-Mrtens) o C Min EN ISO 314 Col filter plugging point (CFPP) - Climte lsses C o C Mx SRPS EN 116 Sulfur ontent mg/kg Mx 1.81 EN ISO 2846 Cron resiue remnnt (t 1% istilltion remnnt) % (m/m) Mx.3.19 EN ISO 137 Sulfte sh ontent % (m/m) Mx.2. ISO 3987 Wter ontent mg/kg Mx EN ISO Cetn inex - > SRPS ISO 4264 Totl ontmintion mg/kg Mx 24.1 EN Copper n orrosion (3 hours t 5 C) Kls 1 1 EN ISO 216 Ai vlue mgkoh/g Mx..5.2 EN 1414 Linoleni Ai Methylester % (m/m) Mx EN 1413 Polyunsturte (>= 3 Doule ons) Methylester % (m/m) Mx. 1 <.2 SRPS EN Methnol ontent % (m/m) Mx..2.8 EN 1411 Monoglyerie ontent % (m/m) Mx EN 1415 Diglyerie ontent % (m/m) Mx EN 1415 Triglyerie ontent % (m/m) Mx EN 1415 Free Glyerine % (m/m) Mx..2.4 EN 1415 Totl Glyerine % (m/m) Mx EN 1415 Group I metls (N+K) Group II metls (C+Mg) mg/kg Mx EN 1418 EN Phosphorus ontent mg/kg Mx EN 1417 High heting vlue MJkg ASTM D Bioiesel ws lene with low sulfur fossil iesel proue in the Oil Refinery from Novi S (hereinfter LSDF) *. Results of the nlysis of the use LSDF inite tht this fuel is in line with SRPS EN 59 (Tle 2). Tle 2. Properties of use fossil iesel (SRPS EN 59:21) Property Units Vlue Metho Property Units Vlue Metho Density 15 o C kg/m SRPS ISO Distilltion t 25 o C V/V SRPS EN ISO 345 IBP o C Distilltion t 35 o C V/V % o C 22.9 Visosity mm 2 /s 3.1 SRPS ISO 314 2% C Flsh point C 65 SRPS EN ISO 2719 SRPS EN ISO 3% C Blur point C -5 SRPS ISO % C Col filter plugging point C -19 EN 116 5% o C Sulfur ontent mg/kg 8.2 ASTM D % o C Wter ontent mg/kg 6 SRPS ISO * LSDF-Low sulfur iesel fuel 4

5 7% o C Cetn inex SRPS ISO 4264 o 3 hours t SRPS ISO 216 C 31.8 Copper n orrosion 8% 5 o 1 C 9% o C Totl ontmintion mg/kg / SRPS EN % o C Apperne - Cler Visul FBP o C Color -.5 SRPS ISO 249 Rest % V/V.8 Oxition stility g/m 3 / SRPS ISO 1225 Loss % V/V.9 Polyyli romti FOX (MIDAC) %m/m 6.6 hyrorons High heting vlue MJkg ASTM D Tle 3 shows min properties of ioiesel n LSDF lens use in the reserh. Tle 3. Properties of use lens of ioiesel n LSDF Vlue Property Units BD-15 BD-25 BD-5 BD-75 Density 15 o C kg/m Visosity mm 2 /s Flsh point o C Sulfur ontent mg/kg Wter ontent mg/kg High heting vlue MJkg Engine n instruments Engine hrteristis n exhust gs emissions of the teste fuels were nlyze for the trtor type Mhinr 65 4WD. Trtor type Mhinr 65 is the ll purpose trtor ( four-wheelrive trtor with smller steering wheels t the front), intene for performing vrious opertions in griulture (si tillge, presowing preprtion, sowing, mehnil n hemil rop re, trnsport...) in smll frmstes whih re most ommon in the Repuli of Seri. The trtors were equippe with Mhinr NE 462R four-yliner, DI, four stroke with ore of 96 mm, stroke of 122 mm, isplement of 3532 m 3, ompression rtio of 19.5:1, rte power of 48.4 kw t 22 rpm, n mximum torque of Nm t 1398 rpm. This trtor engine is of Tier II genertion type. Fuel injetion pump is the MICO Bosh (VE Type). Fuel injetion pump is single plunger, rotry istriutor pipe pump inorporting entrifugl spill port governor. Fuel injetion pressure rs. The trtor engine ws onnete to the eletri Eggers Dynmometer Type 31/ME through the power tke-off shft (ury level <1%, Fig. 1). Fuel onsumption ws mesure y the volume metho pplying the flowmeter Pierurg 2911 (ury level ±.5%). Exhust gs emissions (NOx, CO, CO 2, ury level 2 ppm, 2 ppm, ±.2% vol. respetively) were mesure y Testo 355 portle nlyzer (Testo GMBH, Lenzkirh, Germny). The tempertures of ooling liqui n engine oil, temperture of ir t the entrne to the sution pipe, n the fuel temperture were mesure y thermoouple LM-35 (ury level ±.5%), HBM- Hottinger Blwin Messtehnik, Germny. The mient onitions (temperture, pressure n reltive ir humiity) were mesure y the evie GFTB-1, Greisinger eletroni GmH, Germny (ury level ±.1 o C,.1 mr,.1% r.f ). The numer of revolutions ws mesure y igitl thometer Testo type (ury level ±.2%). 5

6 Figure 1. The sheme of mesuring equipment 1-Teste trtor, 2-Dynmometr eggers 31/MEM, 3-Exhust gs nlyzer Testo 335, 4- Fuel flowmeter Pierurg 2911, 5-Amient onitions mesuring instrument, 6- Engine spee guge, 7- Aquisition (Spier 8), 8-PC t 1 -sution ir temperture, t 2 -ooling liqui temperture, t 3 -fuel temperture, t 4 -engine oil temperture, t 5 -outsie temperture, t 6 -exhust gses temperture The tests were onute in the registere OECD Lortory for Power Mhines n Trtors (LMT) from Novi S, Seri Experimentl proeure The performnes of the engine using ifferent fuel types (prt 2.1) were evlute in ompline with the OECD stnr (CODE 2) for the purpose of the offiil testing of griulturl trtors [26]. The testing first inlue 6 points of the governor ontrol of urve, with full lo (Fig. 2, points re mrke with tringles). Point P 1 represents the rte power. Point P 2 is the power t torque of 85% whih is hieve in the point P 1. Point P 3 is the power t torque of 75% hieve in the point P 2. Point P 4 is the power t torque of 5% hieve in the point P 2. Point P 5 is the power t torque of 25% hieve in the point P 2. Point P 6 represents the hrteristis of unloe engine [27]. In ition to the points on the governer ontrol urve, the mesuring lso inlue the prt of the urve from point P 1 to the mximum torque. During the testing, points in this prt of the urve were mesure t every 2 rpm (P7- vlue mesure t 2 rpm, P8-18 rpm, P9-16 rpm, P1-14 rpm, P11-vlue mesure t mximum torque, n P12-12 rpm). Figure 2. Opertion points of CODE 2 n ISO , C1 (8-point yle) 6

7 Speifi Fuel Consumption (g/kwh) nnom=22 rpm Therml effiieny nnom=22 rpm Terque (Nm) nnom=22 rpm Power (kw) nnom=22 rpm Exhust gs emissions were mesure in ompline with the stnr ISO , C1 (8-point yle) [28]. Point I (Fig. 2, points re mrke with irles) ws otine in the regime of mximum power t the rte spee. Point II is the point t torque of 75% hieve in the point I n t rte spee. Point III is t torque of 5% hieve in point I n t rte spee. Point IV is the point with loe engine t torque of 1% hieve in point I n t rte spee. Point V represents the operting regime t pek torque. Point VI is the operting regime t pek torque of 75% n t the numer of revolutions whih orrespons to the pek torque. Point VII is the operting regime t pek torque of 5% n numer of revolutions whih orrespons to the pek torque. Point VIII is the operting regime of the unloe engine t ile spee. Sttistil nlyses were rrie out s one-wy ANOVA with one fixe ftor (fuel len). The vlues represent verge vlues of 6 mesurings performe in one hour. Differenes etween men vlues for ifferent engine performne vriles onsiere were teste y the Dunn s intervl test (P <.1) [26]. All sttistil nlyses were performe using the Sttisti 1 softwre pkge. 3. RESULTS AND DISCUSSION 3.1. Engine performne Engine performne, torque (Nm), power (kw), speifi fuel onsumption (g/kwh) n therml effiieny re given in Figure 3 for ll teste fuels with respet to the numer of revolutions of the rnkshft Engine spee (rpm) Engine spee (rpm), ,4,35, ,25,2,15,1, Engine spee (rpm), Engine spee (rpm) BD 1 BD 75 BD 5 BD 25 BD 15 LSDF Figure 3. Power hrteristis of the engine with ifferent test fuels 7

8 The use of LSDF proue rte power of 44.1 kw t 22 rpm. The test fuels BD-15, BD- 25, BD-5, BD-75 n BD-1 proue the rte power of 44.25, 42.85, 42.26, n kw, respetively. In omprison to the LSDF the test fuels BD-15, BD-25, BD-5, BD-75 n BD-1 h lower power y -1.51, 1.21, 2.86, 5.36 n 5.74%, respetively, for the entire mesuring rnge. Although the use ioiesel h lower heting vlue thn the LSDF (y 12.84%), test fuel BD-15 showe n inrese of.54% t rte power with respet to the LSDF, n for the entire mesuring rnge tht inrese ws 1.51%. This power inrese omplies with the results of other uthors [29] whih oul e expline in ifferent wys. Nmely, high ontent of oxygen in ioiesel fuel (out 11%) [12] enles more omplete omustion. Also, fuel ensity is inrese y lening ioiesel with fossil iesel. Consiering the ft tht the fuel injetion pump is voluminous more fuel mss n flow in the sme volume whih further results in more engine power. The thir reson for power inrese is kinemti visosity (kinemti visosity of fuel BD-15 ws 3.9% higher thn tht of the LSDF). Aprt from the negtive effet of inrese kinemti visosity on the tomiztion proess n ir-fuel mixing, slight inrese n ffet positively the engine performnes sine it enles less internl fuel lekge (etween the pump n syringe elements) [3]. Tle 4 (enlose within the pper) shows verge power vlues (the verge of 6 mesurements) for 12 points n ll teste fuels. Letters in the tle represent the rnking of the otine vlues for the mesuring points. The sme letters in one olumn inite tht the vlues re of the sme rnking, tht is, tht there is no sttistilly signifint ifferene etween the otine vlues for the signifine threshol of.1. The ANOVA nlysis inite tht ll teste fuels h high sttistilly signifint power _ ifferenes (p =.) for the entire mesuring rnge ( P i, i 1, ). The Dunn s test showe high sttistilly signifint power ifferenes in ll fuel types exept for the LSDF n BD-15, n BD-75 n BD-1 whih showe no sttistilly signifint ifferenes. The lowest speifi fuel onsumption ws reore with the LSDF while the BD-1 fuel h the highest fuel onsumption. With respet to the LSDF, the test fuels BD-15, BD-25, BD-5, BD-75 n BD-1 h higher speifi fuel onsumption y 1.32, 1.76, 3.49, 8.56 n 13.35%, respetively, for the entire mesuring rnge. Low heting vlue n high fuel ensity re the resons for suh inrese in the speifi fuel onsumption. Given tht the heting vlue of fuel BD-15 BD-25 BD-5 BD-75 n BD-1 less thn the LSDF for 1.96, 3.16, 6:49, 9.92, 12.84%, respetively, it n e onlue tht the omustion of mixture ioiesel n fossil iesel fuel is more ompletely. Aoring to the ANOVA it ws onlue tht ll teste fuels h high sttistilly signifint ifferenes in the speifi fuel onsumption (p =.) for the entire mesuring rnge _ ( P i, i 1, ). The Dunn s test showe high sttistilly signifint ifferenes in speifi fuel onsumption etween ll fuel types exept for BD-15 n BD-25 whih showe no sttistilly signifint ifferenes (T. 5). Averge vlue of therml effiieny ws.256 for the LSDF for the entire mesuring rnge _ P i, (( i 1, ). With respet to the LSDF, the test fuels BD-15, BD-25, BD-5, BD-75 n BD-1 h higher therml effiieny y, 1.95, 3.52, 4.29 n 3.13%, respetively, for the entire mesuring rnge. The highest vlues of this prmeter were hieve y using the fuel type BD-75. All fuel types showe higher therml effiieny vlue with the inrese of engine lo. Bse on the ANOVA it ws onlue tht ll teste fuels h high sttistilly signifint _ ifferenes in therml effiieny (p =.) for the entire mesuring rnge (, i 1, ). The P i 8

9 CO2 emission (%) Dunn s test showe high sttistilly signifint ifferenes etween the following pirs: LSDF n BD-25, LSDF n BD-5, LSDF n BD-75, LSDF n BD-1, BD-5 n BD-15, BD-5 n BD- 25, n etween BD-25 n ll other fuels (T. 6) In spite of the reue heting vlue n inrese speifi fuel onsumption, therml effiieny ws inrese in ll fuels with high ioiesel ontent whih enle more omplete omustion. Similr results were reore in the stuy with low power engines of 7.5 kw when therml effiieny ws improve with lens BD-2 n BD-3 [31]. Cnki n Vn Gerpen [32] oserve tht ioiesel ws injete erlier in omprison to the fossil iesel fuel. When injete erlier ioiesel is lso omuste erlier whih improves therml effiieny. Also, higher ioiesel etne numer uses shorter ely time of fuel omustion n provies more time for omplete omustion [31, 33] Exhust gs emissions Anlysis of exhust gs emission inlue the emissions of CO 2, CO, NOx n the temperture of exhust gses The CO 2 emissions The igrm (Fig. 4) shows the CO 2 emissions se on the hnge of engine lo for ll test fuels. The CO 2 emission from ll test fuels inrese with the engine lo inrese. In omprison to fossil iesel, the fuel types BD-15, BD-25, BD-5, BD-75 n BD-1 use the reution of CO 2 emission y, on verge, 2.5, 5.1, 5.91, 7.7 n 8.99%, respetively Engine lo (%) LSDF BD-15 BD 25 BD 5 BD 75 BD 1 LSDF BD 15 BD 25 BD 5 BD 75 BD 1 Figure 4. Vrition of CO 2 with engine lo for ifferent fuels ( - rte spee, 22 rpm, engine spee t mx. torque) Figure 5 shows the reltive hnge in the CO 2 emission with respet to LSDF. The emission vritions ourre with ifferent test fuels n for ifferent ISO stnr n C1 engine test points. The igrm lso shows tht the inrese ioiesel shre in fossil iesel uses the reution of CO 2 emission t lower engine lo. This further les to erese in the omustion effiieny. The min reson for this is high kinemti visosity with high ioiesel ontent. Nmely, minor inrese of kinemti visosity hs positive effet on the engine performnes ue to the low internl fuel lekge. However, it hs negtive effet on the tomiztion proess, ir-fuel mixing n the qulity of omustion of the forme len [34]. Also, some uthors [35-39] explin the reue CO 2 9

10 NOx emission (ppm) Speifi NOx emission (g/kwh) Differene in CO2 emission (%) (reltive to LSDF) emission with lower ontent of elementry ron n hyrogen in ioiesel with respet to fossil iesel fuel BD-15 BD-25 BD-5 BD-75 BD-1-18 I II III IV V VI VII VIII -2 Mesure point Figure 5. Perentge hnge of the CO 2 emission (reltive to LSDF) Aoring to the ANOVA it ws onlue tht ll teste fuels gve high sttistilly _ signifint ifferenes (p =.) in the CO 2 emissions for the entire mesuring rnge ( P i, i 1, ). Dunn s test showe sttistilly signifint ifferenes in the CO 2 emission for ll teste fuels exept for BD-25 n BD-5 whih showe no sttistilly signifint ifferene (T. 7) The NOx emissions The onute reserhes showe tht higher engine lo use liner inrese of NOx emission in ll test fuels t rte spee (Fig. 6). The highest NOx emission ws mesure in the Point P-VI. On the other hn, speifi NOx emission (g/kwh) ws reue in ll test fuels s the engine lo inrese. The lo inrese of 5% t rte spee i not use ny hnges in the speifi NOx emission (Fig. 6) Engine lo (%) Engine lo (%) LSDF BD-15 BD 25 BD 5 BD 75 BD 1 LSDF BD 15 BD 25 BD 5 BD 75 BD 1 LSDF BD-15 BD 25 BD 5 BD 75 BD 1 LSDF BD 15 BD 25 BD 5 BD 75 BD 1 ) ) Figure 6. Vrition of NOx with engine lo for ifferent fuels ) in ppm, ) in g/kwh ( - rte spee, 22 rpm, engine spee t mx. torque) The inrese shre of ioiesel in the len uses high NOx emission (Fig. 7). In omprison to LSDF, the fuel types BD-15, BD-25, BD-5, BD-75 n BD-1 h higher NOx emission y, on verge, 1.51, 3.1, 4.89, 9,5 n 11.38%, respetively. The results otine from this stuy re similr to those stte y EPA (Environmentl protetion geny) [4]. Aoring to the EPA the use of BD-2 les to n inrese in the NOx emission y 2 % in omprison to fossil iesel. 1

11 Exhust temperture (oc) Differene in NOx emission (%) (reltive to LSDF) 2 BD-15 BD-25 BD-5 BD-75 BD I II III IV V VI VII VIII Mesure point Figure 7. Perentge hnge of the NOx emission (reltive to LSDF) Aoring to the ANOVA it ws onlue tht ll teste fuels h high sttistilly signifint ifferenes (p =.) in the NOx emissions for the entire mesuring rnge ( P i, i 1, ). Dunn s test showe high sttistilly signifint ifferenes in the NOx emission for ll teste fuels exept for the LSDF, BD-15 n BD-25 n etween BD-75 n BD-1 (T. 8). The NOx emission is onitione y the omustion temperture, oxygen onentrtion, pek pressure n time [41]. Figure 8 shows the exhust gses tempertures se on the hnges of the shre of ioiesel in the len. Figure 9 shows the hnge of NOx emission se on the hnge of the oxygen onentrtion in the omustion prouts. It is lrey known tht the NOx emission inreses s the temperture of omustion prouts inreses. Sine the inrese ontent of ioiesel in LSDF reues the exhust gs tempertures, then the inrese emission of NOx is most proly the onsequene of hrteristis of rw mterils use for ioiesel proution. Nmely, Lpuerto [42] sttes tht NOx emission is ffete y ioine numer. Aoring to the results from these reserh, NOx emission will e the sme s from fossil iesel fuel y using ioiesel with ioine numer elow 5 whih n e hieve with ioiesel proue from pig ft (ioine numer of pig ft is 46-66). On the other hn, sunflower oil hs ioine numer of (the ioine numer of teste ioiesel ws 132). _ Bioiesel ontent (%v/v) Point I Point II Point III Point IV Point V Point VI Point VII Point VIII Figure 8. Chnge of the exhust gses temperture epening on the ioiesel ontent The reson for high NOx emission lies in the high ontent of olei i in ioiesel proue from sunflower oil (over 64 %). Knothe et l. [43] investigte the NOx emission from fossil iesel fuel n ioiesel with ifferent ontent of ftty is. The uthors onlue tht ioiesel with high ontent of plmiti methyl ester (C 16:) n luri methyl ester (C 12:) h lower ontent of NOx in 11

12 Differene in CO emission (%) (reltive to LSDF) CO emission (ppm) Speifi CO emission (g/kwh) omprison to the fossil iesel fuel. However, they onlue tht high ontent of olei methyl ester (C 18:1) in ioiesel inrese the NOx emission The CO emissions The inrese in lo les to the inrese of the CO emission whih is the onsequene of ir exess rtio reution in the engine yliner (Fig. 9). The onute reserh showe tht the highest CO onentrtions were emitte y using the LSDF, n the lowest emissions ourre with the use of BD-1. In omprison to the LSDF, the test fuels BD-15, BD-25, BD-5, BD-75 n BD-1 use the reution in CO emission y, on verge, 1.84, 3.79, 9.3, n 13.15%, respetively (Fig. 1). With n inrese in the engine lo the speifi emission of CO (g/kwh) is onsierly reue y using the fuels with higher ontent of ioiesel. Conversely, this ifferene is proportionlly smll with the low engine lo. The reson for this lies in the ft tht the fuel with high ioiesel ontent hs higher kinemti visosity in omprison to the LSDF. Therefore, low lo n low temperture in the engine yliner use poor tomiztion n ir-fuel mixing. On the other hn, inrese lo les to the higher temperture of the engine yliner whih results in etter fuel tomiztion. All the previously mentione further results in etter ir-fuel mixing, etter omustion, n reution of the CO emission [26, 44]. Besies the poor tomiztion, the use of ioiesel t low lo reues the CO emission in omprison to LSDF. This is use y higher ontent of oxygen in ioiesel whih filittes the omustion proess [35] Engine lo (%) LSDF BD-15 BD 25 BD 5 BD 75 BD 1 LSDF BD 15 BD 25 BD 5 BD 75 BD Engine lo (%) LSDF BD-15 BD 25 BD 5 BD 75 BD 1 LSDF BD 15 BD 25 BD 5 BD 75 BD 1 ) ) Figure 9. Vrition of CO with engine lo for ifferent fuels ) in ppm, ) in g/kwh ( - rte spee, 22 rpm, engine spee t mx. torque) BD-15 BD-25 BD-5 BD-75 BD-1 I II III IV V VI VII VIII -6 Mesure point Figure 1. Perentge hnge of the CO emission (reltive to LSDF) 12

13 Bse on the ANOVA it ws onlue tht there were high sttistilly signifint ifferenes in the CO emissions (p =.) from ifferent fuel types for the entire mesuring rnge _ ( P i, i 1, ). Dunn s test showe sttistilly signifint ifferenes in the CO emissions from ll fuel types. 4. CONCLUSIONS The experimentl reserh hs een onute with the im of etermining the ojetive possiilities of using ioiesel from sunflower in the engines of meium power griulturl trtors. Therefore, engine performnes n exhust gs emissions were ompre y using pure ioiesel, fossil iesel n lens of fossil iesel with 15, 25, 5 n 75%v/v ioiesel. Bse on the results, the following onlusions n e rwn: In omprison to fossil iesel, ioiesel inrese in the len les to the power reution whih results in the low heting vlue of ioiesel n high kinemti visosity. The BD-15 fuel represents n exeption sine it showe slight inrese of power in omprison to other fuels, inluing the fossil iesel fuel. As ioiesel inreses in the lens, the speifi fuel onsumption for ll teste fuels lso inreses in omprison to fossil iesel. However, the inrese in speifi fuel onsumption, whih ourrs s result of lening ioiesel with fossil iesel, is lower thn the erese in heting vlue. This is the result of higher ensity n lower ioiesel heting vlue in omprison to fossil iesel fuel. Therml effiieny slightly inreses with the inrese of ioiesel shre in the len, whih is the result of fster n more omplete fuel omustion. The inrese of ioiesel in the len les to the reution of CO 2 n CO emissions. With higher los CO 2 emission is reue less thn the CO emission. This is the result of more omplete fuel omustion t higher engine lo. The inrese of ioiesel shre in the lens les to the reution of exhust gs tempertures in ll opertion regimes. At lower exhust gs tempertures NOx emission still inreses with n inrese of ioiesel. This is the result of inrese oxygen ontent in the omustion prouts 5. ACKNOWLEDGMENTS This work ws supporte y the Ministry of Eution n Siene, the Repuli of Seri (projet: Improvement of the qulity of trtors n moile systems with the im of inresing ompetitiveness n preserving soil n environment, No TR-3146). 6. REFERENCES 1. ** Tring Eonomis, 2. Tiegng Fng. Bioiesel omustion in n optil HSDI iesel engine uner low lo premixe omustion onitions. Fuel 29, 88: Krishnkumr J. Tehnil spets of ioiesel proution from vegetle oils, Therml Siene 28, 12(2):

14 4. Mićić R.: Hiroesulfristion, Monogrphy, Fulty of Tehnology Novi S 211, (in Serin lnguge) 5. Lpuert M, Arms O, Fernnez JR. Effet of ioiesel fuels on iesel engine emissions. Progress in energy n omustion siene : LM Chen, Qi DH, Geng H, Bin YZ, Liu J, Ren XC. Comustion n performne evlution of iesel engine fuele with ioiesel proue from soyen rue oil. Renewle Energy 29, 34(12): Imt Tymz, Muhit Sengil: Performne n emission hrteristis of iesel engine using esters of plm olein/soyen oil lens, Int. J. Vehile Design 21, 54(2): Ozsezen AN, Cnki M. The emission nlysis of n IDI iesel engine fuele with methyl ester of wste frying plm oil n its lens. Biomss Bioenergy : Rmesh D, Smpthrjn A. Investigtions on Performne n Emission Chrteristis of Diesel Engine with Jtroph Bioiesel n Its Blens. Agriulturl Engineering Interntionl: the CIGR E jurnl, Mnusript EE 7 13, 28, Song J-T, Zhng C-H. An experimentl stuy on the performne n exhust emissions of iesel engine fuelle with soyen oil methyl ester. P I Meh Eng D-J Aut 28;222: Hzr H. Effets of ioiesel on low het loss iesel engine. Renew Energy : Mustpić Z, Kričk T, Stnić Z. Bioiesel s lterntive engine fuel. Energy. 26, 55(6): Rjn K, Senthil Kumr KR. The Effet of exhust gs reirultion (EGR) on the performne n emission Chrteristis of iesel Engine with Sunflower oil methil ester. Interntionl Journl of Chemil Engineering Reserh 29. 1(1): Fogli TA, Nelson LA, Dunn RO, Mrmer WN. Low-Temperture Properties of Alkyl Esters of Tllow n Grese. JAOCS : Prrill1 J, Muñoz M, Moreno F. Enurne n urility in ioiesel powere engines. Deprtment of Mehnil Engineering. University of Zrgoz. Spin 16. Hoshino, T., Iwt Y., Koseki H.: Oxition stility n risk evlution of ioiesel, Therml Siene 27, 11(2): Monyem A, Vn Gerpen JH. The effet of ioiesel oxition on engine performne n emissions. Biomss Bioenergy 21. 2: Dhnnjy, D.A., Suhir, C.V., Mohnn, P.: Comustion hrteristis of iesel engine operting of jtroph oil methyl ester, Therml Siene 21, 14(4): Tešić M., i sr.: The possiility of prouing n using ioiesel in AP Vojvoin, Vojvoins Aemy of Sienes n Arts, Novi S 29., (in Serin lnguge) 2. Brkić M., Jnić T.: New estimte of types n quntities of iomss for proution of energy in Vojvoin, Journl Cont. Agr. Engng. 21, 36(2), (in Serin lnguge) 21. Furmn T. Bioiesel, Liqui fuel. Monogrphy, Bioiesel lterntive n eology liqui fuel, Fulty of Agriulture Novi S, 25: (in Serin lnguge) Nikolić R, et l: The sitution n equipping with griulturl mehniztion in 211 yer. Trtors n Power Mhines (5): (in Serin lnguge) 24. Tomić M, Mtić-Kekić S, Svin L, Desni E, Deović N, Simikić M, Ponjičn O, Ašonj A. Optimiztion of the lotions of overhul pities for griulturl engineering in Seri y 14

15 pplying integer progrmming. Afrin Journl of Agriulturl Reserh 211, 6(15): Živkov-Blš M, Tomić M, Mihljev Ž, Stojnov I, Kpetnov M, Pronov-Rulović J, Potkonjk D. Sunflower ke- y-prout in ioiesel proution, 22 n Interntionl symposium Sfe foo proution, Proeeings 211: Miln I, Cmps M, Pone e Leon JL, Snhez-Giron V. Performne n emissions of n griulturl iesel engine fuelle with ifferent iesel n methyl estr lens. Spnish Journl of Agriulturl Reserh 21. 8(2): OECD, 29. Stnr oe for the offiil testing of griulturl n forestry trtor performne. Coe 2. Ferury **Exhust Emission Legisltion. Diesel n Gs engines. Engines n Systems. June Goignur S, Murthy CHS, Rey RP. 6BTA 5.9 G2-1 Cummins engine performne n emission tests using methyl ester mhu (Mhu ini) oil/iesel lens. Renewle Energy : Ust N. An experimentl stuy on performne n exhust emissions of iesel engine fuelle with too see oil methyl ester. Energy Convers. Mnge : Rhemn H, Phtre AG. Diesel engine emissions n performne from lens of krnj methyl ester n iesel. Biomss Bioenerg 24;27: Cnki M, Vn Gerpen JH. Comprison of engine performne n emissions for petroleum iesel fuel, yellow grese ioiesel, n soyen oil ioiesel. Trns ASAE 23;46: Lin C-Y, Lin H-A. Engine performne n emission hrteristis of threephse emulsion of ioiesel proue y peroxition. Fuel Proess Tehnol 27;88: Gumus M, Ksifoglu S. Performne n emission evlution of ompression ignition engine using ioiesel (priot see kernel oil methyl ester) n its lens with iesel fuel. Biomss Bioenergy : Ozsezen AN, Cnki M, Turkn A, Syin C. Performne n omustion hrteristis of DI iesel engine fuele with wste plm oil n nol oil methyl esters. Fuel 29;88: Utlu Z, Ko k MS. The effet of ioiesel fuel otine from wste frying oil on iret injetion iesel engine performne n exhust emissions. Renew Energ 28;33: Keskin A, Gürü M, Altıprmk D. Influene of tll oil ioiesel withmgnmo se fuel itives on iesel engine performne n emission. Bioresoure Tehnol 28;99: Lin C-Y, Lin H-A. Engine performne n emission hrteristis of threephse emulsion of ioiesel proue y peroxition. Fuel Proess Tehnol 27;88: Shoo PK, Ds LM, Bu MKG, Nik SN. Bioiesel evelopment from high i vlue polng see oil n performne evlution in CI engine. Fuel 27;86: EPA - Environmentl protetion geny. A Comprehensive Anlysis of Bioiesel Impts on Exhust Emissions. Drft tehnil report Gonzlez Gomez ME, Howr-Hilige R, Lehy JJ, O reilly T, Supple B, Mlone M. Emission n performne hrteristis of 2 liter Toyot iesel vn operting on esterifie wste ooking oil n minerl iesel fuel. Environ. Monit. n Assess 2. 65: Lpuert, M., Arms, O., Roríguez-Fernánez, J.: Effet of ioiesel fuels on iesel engine emissions, Progress in Energy n Comustion Siene (2):

16 Tle 4. Engine power (kw) for ifferent fuel lens n ifferent OECD engine testing points 43. Knothe G. Depenne of ioiesel fuel properties on the struture of ftty i lkyl esterrs. Fuel Proess. Tehnol : Goignur S.K., Murthy Ch.S., Rey, R.P.: The effet of krnj oil methyl ester on kirloskr HA394DI iesel engine performne n exhust emissions, Therml Siene 21, 14(4): P 1 1 P 2 P 3 P 4 P 5 P 6 P 7 P 8 P 9 P 1 P 11 P 12 Men LSDF 44,1 2 4,61 31,15 21,6 1,59 4,35 42,27 4,52 38,83 36,79 35,26 28,47 28,68 BD 15 44,25 41,68 31,41 21,44 1,89 4,39 43,85 41,17 38,8 35,69 34,51 28,15 28,69 BD 25 42,85 39,97 31,17 21, 1,64 4,3 42,2 39,77 38,43 36,31 34,31 28,27 28,36 BD 5 42,26 4,22 29,92 2,53 1,22 4,29 41,96 39,1 37,97 34,77 33,57 27,89 27,81 BD 75 41,41 38,96 29,56 19,47 9,94 4,29 41,37 38,5 37,61 35,73 33,99 26,74 27,51 BD 1 41,21 38,95 29,54 19,423 9,8 4,13 41,8 38,38 37,37 35,4 34,2 26,58 27,37 Men 42,66 4,7 3,46 2,49 1,35 4,29 42,12 39,57 38,5 35,78 34,31 27,68 1 P1 - rte power, P2 vlue t 85 % of torque hieve in the Point P1, P3 vlue t 75 % of torque hieve in the Point P2, P4 vlue t 5 % of torque hieve in the Point P2, P5 vlue t 25 % of torque hieve in the Point P2, P6 unloe engine, P7- vlue mesure t 2 rpm, P8-18 rpm, P9-16 rpm, P1-14 rpm, P11-vlue mesure t mximum torque, 2 Rnking of the vlue in the sme olumn. There is no sttistilly signifint ifferene t signifine threshol of.1 etween the vlues mrke with the sme letter in one olumn n. P 1 1 P 2 P 3 P 4 P 5 P 6 P 7 P 8 P 9 P 1 P 11 P 12 Men 266,7 267,5 275,7 285,1 279,8 31,7 256,2 264,7 25,9 27,5 267,9 271,1 246,3 256,8 237,5 248,2 238,9 252,2 247,4 264,5 256,5 251,9 255,1 26,6 219,1 219,1 227,5 211,4 238,3 256,1 e 363,4 e 368,2 369,8 376,1 394,5 411,9 Men 295,7 283,5 325,2 41,1 547,1 1153,2 279, 279,4 263,6 246,6 256, 228,6 P 1 1 P 2 P 3 P 4 P 5 P 6 P 7 P 8 P 9 P 1 P 11 P 12 Men,292,34,316,314,355,256,297,3,39,3,362,256,291,32,338,313,353,261,292,37,335,33,393,265,39,296,322,329,361,354,338,342,362,267,348,264 Men,28,292,254,22,152,72,296,296,314,335,323,362 P12-12 rpm. Tle 5. Speifi fuel onsumption (g/kwh) for ifferent fuel lens n ifferent OECD engine testing points LSDF 277, ,3 322,8 375,9 496,2 1114,9 267,1 BD ,2 272,1 327,5 38,1 497, 1121,7 268,2 BD ,3 276, 315,9 392,6 489,1 1159,3 271,7 BD 5 32,4 278,1 32,1 47,7 547,8 119,6 28,3 BD ,8 296,8 318,3 447,4 61,4 1175,4 289,7 BD 1 313,6 36,8 346,2 456,9 642,5 1237,8 296,9 1,2 See Tle 4 Tle 6. Therml effiieny for ifferent fuel lens n ifferent OECD engine testing points LSDF,28 2,287,241,27,157,7,291 BD 15,284,291,242,29,16,71,296 BD 25,281,291,254,25,164,69,295 BD 5,275,299,26,24,152,75,297 BD 75,273,291,271,193,141,73,298 BD 1,284,291,258,195,139,72,3 1,2 See Tle 4 16

17 Tle 7. CO 2 emissions (%) for ifferent fuel lens n ifferent ISO , C1 engine testing points P I 1 P II P III P IV P V P VI P VII P VIII Men LSDF BD BD BD BD BD e Men P I emission t mximum power n rte spee, P II emission t 75% of torque hieve in the point I n t rte spee, P III emission t 5% of torque hieve in the point I n t rte spee, P IV emission t 1% of torque hieve in the point I n t rte spee, P V emission t mx. torque, P VI emission t 75% of mx. torque t numer of revolutions orresponing to the mx. torque, P VII emission t 5% of mx. torque t numer of revolutions orresponing to the mx. torque, P VIII emission from the unloe engine t ile spee. 2 Rnking of the vlue in the sme olumn. There is no sttistilly signifint ifferene t signifine threshol of.1 etween the vlues mrke with the sme letter in one olumn Tle 8. NOx emissions (g/kwh) for ifferent fuel lens n ifferent ISO , C1 engine testing points P I 1 P II P III P IV P V P VI P VII P VIII Men LSDF e 16.5 e BD e BD BD BD BD Men ,2 See Tle 7 Tle 9. The CO emissions (g/kwh) for ifferent fuel lens n ifferent ISO , C1 engine testing points P I 1 P II P III P IV P V P VI P VII P VIII Men LSDF BD BD BD BD e e e BD f 1.68 e e.4 f f Men ,2 See Tle 7 17