TNG QUAN PHT TRIN NHIN LIU SINH HC TRN TH GII

Pham Van Hoi - i hc Nng nghip H NiPeter Oosteveer and Jan Japenga - i hc Wageningen, H Lan

Nhng kh khn khng phi l tng mi, m l vic thot ra khi cch ngh ccch ngh n su trong mi ng ngch ca no trng chng ta. (John Maynard Keynes, 1935)

1. Sn xut nhin liu sinh hc v d boNhin liu ha thch l nng lng c u th vt tri trong nn kinh t ton cu t cch mng cng nghip cui th k 18, c bit l trong na sau ca th k 20 khi th gii tri qua nhng tin b mnh m trong cng ngh v cng nghip ha. Khng hong nng lung nhng nm 1970s lm cho nn kinh t th gii v cng chng mt bi hc cay ng khi con ngi t khp ni trn th gii ngy cng ph thuc vo nhin liu ha thch cho cuc sng hng ngy. Tuy nhin, nhin liu ha thch khng phi v hn v s cn kit vo nhng nm 1950 v 1960 (FAO 2007). Trong iu kin cn kit nhin liu ho thch v cc vn kh thi lin quan gy nhim mi trng t vic s dng ngun nhin liu ny, vic tm kim v pht trin cc ngun nng lng sch, thay th l cn thit v cp bc. Trong s cc ngun nng lng ti to ny, sinh khi l ngun nng lng quan trng nht (Bng 1)

Bng 1: Cc ngun nng lung ti to v d boLoi nng lng ti to Nm / Lng (triu tn du qui i) % vo nm 2040

2001201020202040

Tng nng lng s cp 10,038.0011,258.015,347.017,690.0100.00

Sinh khi 1,080.001,291.02,221.02,843.016.07

Thu in 223.00255.0296.0308.01.75

Thu in nh 9.5016.062.091.00.51

Gi 4.7035.0395.0580.03.28

Pin mt tri 0.201.0110.0445.02.51

Nhit mt tri 4.1011.0127.0274.01.55

Nhit in mt tri 0.100.49.029.00.16

a nhit 43.0073.0194.0261.01.47

Thu triu 0.050.12.09.00.05

Tng nng lng ti to 1364.501682.53416.04844.0

% nng lng ti to 13.6014.322.027.427.40

Ngun: OECD (trch trong Carioca 2010).

Nhin liu sinh hc (ethanol sinh hc v diesel sinh hc) l cc ngun nng lng c to ra t sinh khi. Mc d ethanol uc bt u c sn xut (cho mc ch nhin liu) t nhng nm 1930s ti Brazil (Walter, Rosillo-Calle et al. 2007) hoc t Th chin II Trung Quc (Zhong, Cao et al. 2010), ngnh cng nghip sn xut cn cng nghip ch thc s pht trin mnh, tng cng qui m, v cc hot ng thng mi t u thp k 80, c bit cc quc gia nh Brazil v M.

Hin nay, khi nim nhin liu sinh hc thng uc s dng ch nhin liu sinh hc lng ch yu cho cc phng tin giao thng vn ti nhm b sung/thay th cho nhin liu ha thch. Sn lng ethanol sinh hc tng ln gp ba ln tnh t nm 2000 n nm 2007, trong M v Brazil ng gp phn ln cho s gia tng ny (xem Bng 1). Diessel sinh hc gia tng thm ch nhanh hn trong cng giai on, t 1 t lt ti gn 11 t lt (Hoogeveen, Faures et al., 2009). Nhu cu nhin liu sinh hc (v sn xut) tng lin quan vi mt s l do di y: 1) Mi trng--nhng quan tm n mi trng khng kh trong lnh l u tin x hi v chnh tr trn ton th gii. V d cc nghin cu u tha nhn rng trn thc t, ethanol t ma ng c th cho php gim pht thi kh nh knh trn 70% so vi xng du truyn thng. Diesel sinh hc cng c kh nng gim thiu lng pht thi tng t (Bng 2); 2) An ninh nng lng--tng ph thuc vo nng lng nhp khu, c bit l trong bi cnh gi xng du bin ng v theo xu hng tng l mt lo lng ph bin, c bit l EU v Hoa K; 3) p lc kinh t v x hi--nhng mong mun pht trin nng nghip, nng thn, to cng n vic lm (Rosillo-Calle & Walter 2006 uc trch dn ti Walter, Rosillo-Calle et al. 2007). Hp 1 trnh by tnh hnh kinh t ca nhin liu sinh hc trong 3 quc gia sn xut NLSH chnh trn th gii trong nhng nm gn y.

Bng 2. Sn xut nhin liu sinh hc v d bo mt s quc giaQuc giaLng cn sn xut(triu lt)% so vi tng lng cn th gii% so vi tng lng xng s dngLng du sinh hc sn xut(triu lt)% so vi tng lng diesel th gii% so vi tng lng diesel s dng

200820172008201720082017200820172008201720082017

M 38,40052,40050414.66.02,0201,7301670.50.5

Brazil 22,10040,500293240.456.67602,5206101.23.6

Trung Quc 6,69010,200982.04.0nananananana

EU 4,40011,900692.24.96,58013,30054543.05.0

n 1,9103,570232.75.6317385320.90.9

Ca-na-a 1,3802,730222.34.1207660231.12.8

Colombia 497796115.25.0218388224.05.3

Thi Lan 4081,790112.111.74875000.00.0

Nam Phi 369683010.01.900000.00.0

In--n-xia 212227000.00.07532,9906120.77.9

Vit Nam 164532000.00.005000.00.0

c1561,000010.53.3911994748.28.2

Philippine105126000.70.5085000.10.8

Th Nh K7781000.91.200000.00.0

Ma-lay-xia7084000.00.04431,140450.40.8

Ethiopia3874000.30.7636000.20.8

Tanzania2943001.02.51053000.82.6

Mozambique2428000.31.9334000.42.2

Peru2240000.20.200000.00.0

Tng77,100127,0005.57.612,30024,4001.52.6

Ngun: OECD/FAO (trch trong Hoogeveen, Faures et al. 2009)

Sn lng ethanol sinh hc trn ton th gii c t 125 t lt vo nm 2017, gp i sn lng nm 2007. Hu ht c sn xut Brazil v xut sang th trng EU v M. Diesel sinh hc s gia tng vi t l cao hn so vi ethanol sinh hc v t gn 24 t lt vo nm 2017. i vi ethanol sinh hc, nhng qui nh bt buc i vi vic pha trn v s dng xng sinh hc lm nhu cu tng v loi nhin liu ny, t thc y cc hot ng thng mi quc t. i vi diesel sinh hc, hu ht cc hot ng thng mi tp trung vo vic xut nguyn liu th, t cc nh my du c ti Malaysia v Indonesia sang th trng EU (OECD/FAO 2008 trch trong Hoogeveen, Faures et al. 2009) (xem Bng 2 trn). Bng 3: Lng pht thi trung bnh ca NLSH so vi nhin liu truyn thng(VT: %)

Ngun: Balat M et al., 2008 (trch trong Demirbas 2009)

Brazil v M sn xut ti lng nhin liu sinh hc ton cu. Mi y, M vt Brazil, tr thnh quc gia sn xut NLSH ln nht trn th gii. Sn xut ethanol ca M ch yu t ng, tng mnh trong nhng nm gn y do c nhng u i v thu, cc qui nh bt buc, v nhu cu s dng ethanol thay th MTBE[footnoteRef:1] trong pha ch xng. S gim gi thnh sn xut, tng gi du v cc loi phng tin mi ra i cho php cho s chuyn i gia ethanol v xng du truyn thng, to ra nhng kch thch cho cc sn phm mi. Nhin liu sinh hc chim 20% ti Brazil v 3% ti M trong tan b lng nhin liu phc v cho hot ng giao thng vo nm 2007 (Hnh 1). [1: Methyl-tertiary-butyl-ether (MTBE) l mt ph gia ho hc nhm tng hm lng oxy trong xng mogas, gip tng hiu sut t xng trong ng c, t gim lng pht thi c hi. Tuy nhin, MTBE sau ny c chng minh l cht gy nhim ngun nc, bi vy b cm s dng M.]

Cn sinh hc (Ethanol sinh hc)Ehtanol c th sn xut t bt k cht hu c c ngun gc sinh hc c hm lng ng nht nh v cc vt cht c th chuyn i sang dng ng nh tinh bt hoc cenllulose. Ma ng, c ci ng, la min ngt .. l nhng v d v sn phm cha ng. La m, la mch v ngl cc sn phm cha tinh bt. Mt phn ng k cc cy ly g v cy thn tho c thnh phn ch yu l cellulose c th c chuyn i sang ng.[footnoteRef:2] Tt c cc loi cy ny/vt liu ny u c th s dng cho sn xut ethanol (Escobar v cng s 2009). [2: V d, Nh my Cng ngh Sinh hc Zesheng Co. Ltd (Sn ng, Trung Quc) sn xut cn t cellulose. 1 tn cn c th sn xut t 7 tn rm r (Zhong 2010). Tuy nhin rm r Vit Nam thng c t ly tro trc khi nng dn chuyn sang v mi.]

Cng ngh sn xut ethanol sinh hc truyn thng da trn c s ln men ng trc tip t ng ma, c ci ng hoc dn tip chuyn i t tinh bt trong ng cc. Ethanol sau c chng ct v tch nc sn xut nhin liu lng (cn). Ti cc quc gia OECD, hu ht cc loi ethanol c sn xut t sn phm cha tinh bt nh ng, la m v la mch. Ngc li, cc quc gia vng nhit i nh Brazil, ethanol c sn xut t ma ng hay mt r ng (mt loi ph phm t sn xut ng) cc quc gia khc (OECD 2008).

Hp 1: Sn xut NLSH ti Brazil, M, v Trung QucBra-xin, Ngnh cn sinh hc gip tit kim $121,3 t trong giai on t 1976-2004. Chi ph to cng n vic lm (VD: o to k nng) ngnh nhin liu rt r, khong $10/vic lm, so vi $80/vic lm ngnh hng tiu dng, v $200/vic lm ngnh cng nghip ho cht / ho du.M, Nm 2010, sn xut 13 t gallons cn, thay th cho 445 triu thng du th -- nhiu hn s du th nhp khu t Saudi Arabia l 55 triu thng. Cn sinh hc gip tit kim cho nc M khong $34 t.Trung Quc, nm 2008 sn xut c 1,5 triu tn, trong 55% t ng v ng cc, 33% t cu c c, v 12% t r mt. Tuy nhin, t nm 2008, Trung Quc cm s dng ng cc sn xut cn. y l l do Trung Quc tng cng nhp khu sn t Vit Nam. Ngnh NLSH ca Trung Quc c tnh s to khong 9 triu vic lm. u tin, tinh bt c chuyn ha thnh ng trong qu trnh ln men nhit cao. ng c sn xut trong qu trnh ny sau s c ln men thnh ethanol bng nm men v cc vi sinh vt khc. Qu trnh chuyn ha t ng cc sang ethanol s to ra mt s sn phm ph giu m dng lm thc n gia sc. Cc sn phm phm ph ny gp phn gim gi thnh sn xut cn sinh hc. Ngoi ra, tn d cy trng v cc sn phm ph c th s dng cung cp nhit v nng lng cho qu trnh sn xut cn sinh hc (OECD 2008).

Trong 2 thp k gn y, sn xut ethanol gia tng mt cch nhanh chng nhiu quc gia mt phn nhm thch ng vi gi du tng. S khuyn khch ca chnh ph v cc qui nh v tiu chun k thut gp phn cho s pht trin ca nhin liu sinh hc. Ethanol c sn xut trn ton cu gia tng gp 3 ln trong giai on 2000-2007 v t ngng 52 t lt vo nm 2007. Hoa K l nc ng u v sn xut NLSH (Biu 1). hu ht cc quc gia, ethanol c sn xut ch yu phc v nhu cu ni a, mc d cc hot ng xut nhp khu NLSH cng ang tng ln nhanh chng. D bo trong thi gian ti, nhu cu NLSH tng s ko theo s m rng v a l trong sn xut ngnh hng ny trn th gii (Biu 2).

Biu 1. Sn xut ethanol sinh hc trn th gii, 2000-2007

Ngun: F.O.Licht 2007 (trch trong OECD 2008).

Biu 2. Cc khu vc sn xut ethanol sinh hc v d bo

Ngun: Berg (2004).

Diesel sinh hcV c bn, diesel sinh hc c th sn xut t du v cc cht bo: 1) Cc cy cha du: nh hi ly, du c Chu Phi, u tng, ht ci du, hng dng, du m curcas, cy l gai, , 2) Du thc vt qua s dng, thu t cc nh hng, khch sn v h gia nh, 3) Cht bo ng vt t cc l m gia sc, nh my ch bin (Escobar, Lora et al. 2009).

Cng ngh ph bin nht s dng trong sn xut diesel sinh hc l da trn qu trnh chuyn ha este ca du thc vt hoc m ng vt. Qu trnh ny tri qua cc bc bao gm tinh lc nguyn liu loi b nc v cc cht gy nhim, sau trn sn phm thu c vi ru (thng l methanol) v mt cht xc tc (thng l NaOH hoc KOH). Cc phn t du (triglycerides) b b gy v tng hp thnh este (diessel sinh hc) v glycelrol, cc sn phm c tch ra v tinh lc. Qu trnh ny cng to ra glycerine s dng cho cng ngh m phm, y dc v thc phm (OECD 2008).

Tng sn lng diesel sinh hc trn th gii cn mc rt thp so vi ethanol, c tnh ch khong 10,2 t lt vo nm 2007. Gn 60% diesel sinh hc c sn xut EU trong Php v c l quc gia sn xut ln nht. Diesel sinh hc ca Hoa K tng nhanh chng trong nhng nm gn y. Vo nm 2010, tng gi tr diesel sinh hc ton cu t ngng 18.4 t la M v k vng t 71 la vo nm 2020 (PikeResearch 2010). Nm 2007 Hoa K tr thnh quc gia ng th hai v sn xut diesel sinh hc trn th gii ch sau c. Cc quc gia khc nh Malaysia v Indonesia bt u sn xut diesel sinh hc v xut sang th trng EU (Biu 3).

Ngoi du thc vt, cc nguyn liu khc cng c th c s dng sn xut diesel sinh hc. Du thc vt qua s dng c thu li t cc nh hng v h gia nh cng c th l mt ngun nguyn liu u vo kh quan cho sn xut diesel sinh hc do cc sn phm ny t c tc dng s dng cho cc mc ch khc.

Biu 3. Sn xut diesel sinh hc trn th gii, 2000-2007

Ngun: EBB (2008), F.O.Licht (2007), IEA (2007), Agra-Informa 2008) (trch trong OECD 2008).

2. S dng nhin liu sinh hcMc d sn lng ethanol v diesel sinh hc gia tng ng k trong thi gian qua, t l cc nhin liu ny ch mc rt nh so vi nhin liu ha thch trong c cu nng lng s dng. T l nhin liu sinh hc trong tng s nhin liu dng trong giao thng vn ti vo khong 20% ti Brazil v 3% ti M trong nm 2007 (Biu 4). Nhin liu sinh hc dng trong lnh vc giao thng c cho l s tng tng mnh trong cc nm ti, c tnh cn sinh hc s chim 7.6% v diesel sinh hc chim 2,6% tng nhin liu dng trong giao thng vo nm 2017.

Nhu cu s dng ethanol tng ch s octan ngy cng ln nhiu quc gia, c bit l M sau khi MTBE b cm s dng v l do nhim mi trng nc. Hin nay, cc loi phng tin giao thng vi ng c c ci tin c th s dng c c ethanol tinh khit ang c nghin cu v pht trin. Tnh theo qung ng lu thng, phng tin s dng cn c th t khong cch tng ng xe cng loi chy xng mogas, mc d nng lng ca cn sinh hc thp hn so vi xng mogas. mt s quc gia, khch hng c th s dng cc phng tin c kh nng chuyn i s dng nhin liu pha ethanol nng cao hoc xng mogas mt cch d dng (Brazil cho lu hnh ph bin loi phng tin ny trong mt s nm qua). Vic ny gip ngi s dng phng tin th trnh c nhng tc ng khi gi xng du hoc gi nhin liu sinh hc t ngt tng ln, hoc hng li khi gi loi nguyn liu no gim. Cc loi phng tin ny to ra lin kt gia th trng xng du v th trng ethanol cht ch hn (OECD 2008).

Biu 4. T l nhin liu sinh hc trong tng s nhin liu s dng trong giao thng vn ti ( mt s quc gia)

Ngun: EBB (2008), F.O.Licht (2007) and IEA (2007) (trch trong OECD 2008).

Nhng c gng a ethanol ra th trng s dng cho cc ng c t trong ch yu l cc loi c t l pha trn thp nh E5, 10. Cc loi xng sinh hc ny c phn phi nhiu quc gia. Vi cc loi xng c t l cn thp ny, hu ht cc loi xe sn xut trong thi gian gn y s khng cn phi ci tin ng c. Cc loi xng sinh hc ny c th phn phi tng t t nh xng mogas trn c s thit b hin ti. Tuy nhin, khi t l pha trn cao hn 30% ethanol, sn phm h hn ch c th s dng cho cc loi xe ci tin ng c. Ethanol c tr s octane cao, bi vy tng gi tr s dng cho xng sinh hc. Xng sinh hc c nhng c tnh k thut tt, mc d hm lng nng lng ch bng 2/3 so vi xng mogas. Tuy nhin, tnh bt n nh cao (d bay hi) ca ethanol s cn nhng iu chnh pha trn , nht l trong iu kin ma h (OECD 2008).

Theo nh (Berg 2004), ethanol s dng cho mc ch nhin liu ngy cng tng trong tng s ethanol c s dng trn ton th gii (Biu 5).

Tng t nh ethanol, diesel sinh hc c pha trn vi diesel truyn thng thng ch t l 5% (B5) v s dng c cho cc loi phng tin chy bng du diesel truyn thng. Ti nhiu quc gia, diesel sinh hc c t l pha ln ti 30% (E30) hay thm ch l 100% (E100). Ti c, B100 c s dng trong mt s nm gn y, v c phn phi ti hn 700 cy xng. Nng lng ca diesel sinh hc ch bng khong 90% so vi diesel truyn thng nhng c tnh nng bi trn v ch s cetan cao hn (so snh nh tnh ton cht lng t ca diesel trong iu kin nn). iu ny c ngha l gi tr s dng ca diesel sinh hc l tng t nh diesel khong (OECD 2008).

Biu 5. S dng ethanol trn Th gii

Bia/ ruNhin liu Cng nghip

3. Th trng nhin liu sinh hc ton cu Th trng nhin liu sinh hc trn th gii hin cn qu nh, c tnh ch khong 5 t lt mi nm, tng t 1 t lt vo nm 2000 (F.O. Flicht 2007 trch trong OECD 2008). Hot ng xut nhp khu ethanol cn b cho phi bi ethanol dng cho mc ch phi nhin liu (VD: cng nghip ch bin nc gii kht v cng nghip ha cht). Tuy nhin t l phn trm ca ethanol phi nhin liu trn th trng ethanol th gii l gim t khong 75% t u th k cho ti gia 50 v 60% trong nhng nm gn y. Tuy nhin, cc t l ny cha phn bit c th gia ethanol nhin liu v phi nhin liu bi v chng c tnh ton trn cng mt m xut nhp khu (tariff lines) (y c th l l do dn n s khc bit vi bo co ca Berg (2004) nh trnh by trn.

Cho n nay, Brazil l quc gia xut khu ethanol ln nht th gii. Vo nm 2006, Brazil xut khu 3,5 t lt ethanol trong s 5 t lt ethanol c mua bn trn th trng th gii (ngoi tr cc giao dch ni b trong th trng EU). M nhp khu hn 50% lng ethanol xut khu trn th trng th gii. Trong s 2.7 t lt ethanol m Hoa K nhp khu nm 2006, c ti 1,7 lt nhp khu trc tip t Brazil, s cn li ch yu t cc quc gia thuc khu vc Caribe (c u i thng mi vi Hoa K). Nhng quc gia ny nhp khu ethanol ngm nc t Brazil ri tch nc v xut khu tr li Hoa K.

Trung Quc gn y cng tr thnh quc gia xut khu ethanol, tuy nhin nh hn nhiu so vi Brazil. Mc d Trung Quc cng xut khu ethanol sang Hoa K v cc quc gia thuc vng Caribe, tuy nhin Trung Quc xut ch yu sang cc nc khu vc chu c bit l Nam Triu Tin v Nht Bn. Chu u l khu vc nhp khu ng hng th hai, vi mt na lng ethanol nhp khu c ngun gc t Brazil. Th trng ethanol quc t chim khong 9% tng lng ethanol sn xut trn th gii (khong 5 t lt) (Biu 6).

Biu 6. Xut nhp khu ethanol trn th gii, 2006

Ngun: F.O.Licht, 2008 (trch trong OECD 2008).

Cc quc gia xut khu diesel sinh hc chnh hin nay l Indonesia v Malaysia v EU l khu vc nhp khu ch yu. Ti M, nh cc chnh sch nhin liu sinh hc m quc gia ny va l ni nhp khu cng nh xut khu diesel sinh hc quan trng. Diesel sinh hc nhp khu c pha vi lng nh du diesel truyn thng (