Hạn chế phát thải chất khí gây hiệu ứng nhà kính với công nghệ ứng dụng khí sinh học trên động cơ đốt trong

383

Tuyen tftp cdng trinh Hdi nghi Cff hoc toiin qudc
Ky niem 30 ndm Vien Cffhgc vd 30 ndm Tgp chi Cff hoc
Hd Ndi, ngdy 8-9/4/2009

Han che phat thai chat khi gay hieu iing nha kinh voi cong nghe ung
dung khi sinh hoc tren dong co" dot trong
Biii Van Ga, Le Minh Tien, Truong Le Bich Tram, Nguyen Van Dong
D(:n hge Dd Ndng
Ton tat: Viec nghien cieu icng dung cdc ngudn ndng liegng tdi sinh la rdt bice bdch nhdm dam bdo an
ninh ndng lugng vd bdo vi mdi trudng trong bdi cdnh ngudn nhien lieu hda thgch dang ngdy cdng cgn
kiet vd SIC dm ddn len ciia bdu khi quyin dang trd thdnh mdi hiem hoa ddi vpi nhdn logi
Viet Nam vdi 80% ddn sd sdng a ndng thdn, chdt thdi him ca trong qud trinh sdn xudt ndng nghiep vd
chdn nudi Id ngudn rdt tot de sdn xudt khi sinh hoc. Ngudi ddn Viet Nam da rdt quen thude vdi ngudn
ndng lugng ndy vd sdn lugng biogas dang gia tdng nhanh chdng. Tuy nhien khi biogas a nude ta hien nay
chii yen chi mdi diing Igi a viic sic dung cho dun ndii. Khi methane cd tdc dung gdy hieu ieng nhd kinh lan
han CO:, vi vay niu thai biogas thica vdo khi cpiyin thi vdn di d nhiim mdi trudng cdng trd nen trdm
trong han.
Trong nhirng cdng trinh trudc ddy chimg tdi dd die tgo ra cdc bd phu kien di chuyin ddi ddng ca xang
vd diesel sang thdnh ddng ca hcang nhiin lieu biogas-ddu md de sdn xudt dien ndng a ndng thdn. Vdi dd
phdt triin ndng lugng biogas nhu hiin nay ciing vdi viec sdn xudt biogas a cdc trgm xie ly nude, cdc bai
chdn lap rac, trong tuang lai gdn, sdn lugng biogas a medc ta se tdng ddng ke, vi vay viec nghien cim
hodn thiin cdng nghi sic dung biogas tren ddng ca tTnh tgi vd heu trie biogas di ldm nhien lieu cung cdp
cho phuang tiin giao thdng ca gidi Id rdt cdn thiit
Bdi bdo ndy gidi thiiu cdng nghi sie dung biogas tren ddng ca ludng nhien lieu vd khd ndng img dung
cdng nghe dd tren phicang tiin ca gidi a ndng thdn.
Viec nghien ciru irng dung cae ngudn nang lugng tai sinh la rat biic bach nham dam bao an
ninh nang lugng va bao ve moi trudng trong bdi canh nguon nhien lieu hda thach dang ngay
cang can kiet va sir am dan len eiia bau khi quyen dang trd thanh mdi hiem hoa doi vdi nhan
loai.

Viet Nam vdi 80% dan sd sdng d ndng thdn, chat thai hii'u ca trong qua trinh san xuit nong
nghiep va chan nudi la ngudn rat tdt de san xuat biogas. Tuy nhien viec sir dung rpng rai biogas
can cdng nghe de bien chimg thanh cac dang nang lugng khac. Bai bao nay gidi thieu cong nghe
chuyen ddi ddng co sir dung nhien lieu Idng sang chay bang biogas. Neu sir dung cong nghe
nay, mdi nam nude ta cd the san xuat 10%) dien nang bang nhien lieu tai tao va giam 6,5%) phat
thai Carbon vao bau khi quyen.
L

S u gia tang nong do CO2 trong khi quyen va tac hai doi voi moi truong

Trong vdng 4,5 ti nam tdn tai, qua dat da eo nhirng ehu ky nong len roi lanh di. Tir thdi
diim euli eiia thdi ky bang ha cuoi ciing, each day khoang 13000 nam, qua dit da ndng len
trung binh 4°C. Ngay nay qua dat nong len nhanh chong. Trong 1 the ky nhiet dp eiia qua dit da


384

Bill Vdn Ga, Le Minh Tiin, Truong Li Bich Trdm, Nguyin Vdn Ddng

tang len 0,5°C. Phan tich mau lay ra tir bang ha cho thay ky nguyen ciia chiing ta ndng nhat tii
hon 600 nam va 20 nam culi cimg cua thi ky XX, su gia tang nhiet do da vugt qua mpi ky luc
vdi dinh cao la nam 1998.
Nhiet dp gia tang nhanh chong nhu vay khien cho thien nhien khdng cd thai gian de thich
nghi. Neu sir gia tang nhiet dp trong qua khii' gay ra do qua trinh tir nhien thi sir gia tang nhiet
dp ngay nay chii yeu la do boat ddng cua eon ngudi.
Can bang nhiet ciia qua dat dugc dam bao khi he thdng khdng tfch Ifjy nang lupng thang du
tir m^t trdi. Ban ngay biic xa mat trdi dugc hap thu bdi khf quyen, dai duong va dai luc va ban
dem cac thanh phan nay truyen ngugc biie xa ra khdng gian trong viing hdng ngoai. Cac tia biic
xa hdng ngoai nay den lupt nd bj hap thu bdi may va mpt sd chat khf ed mat trong khf quyen.
Cac chat khi gay hieu ung nha kinh phan xa lai mpt phan biie xa nay ve mat dat va lam nong Idp

khi quyen dudi ciing: Dd la hieu ung nha kfnh. Klidng cd hieu irng nay, nhiet dp trung binh ciia
mat dat la -18°C thay vi +15°C nhu hien nay. Hieu ung nha kfnh la mpt hien tugng tu nhien
khdng the thieu tren hanh tinh xanh cua chung ta. Tuy nhien khi tac dpng cua nd vugt qua miic
cho phep thi nd gay ra nhung hau qua nghiem trgng ddi vdi mdi trudng.
Trong so nhQng chat khf gay hieu irng nha kfnh thi CO2 chiem den 50%) tae dung. Tir khi
bat dau thdi ky cong nghiep den nay (khoang 200 nam), sir phat thai CO2 vao bau khf quyen da
khdng ngirng gia tang. Ndng do CO2 hien nay da tang 35%) so vdi thdi ky tien cdng nghiep, vupt
xa ndng do cua ehiing 600 000 nam trudc. Ndng do CO2 da tang tii' 280ppin d thdi ky tien cong
nghiep den 379ppm vao nam 2005. Mue tang trung binh cua CO2 la +l,5ppm/nam trong
khoang 1970 den 2000 va +2,1 ppm/nam trong khoang 2000 den 2007. Cae hoat dpng eua con
ngudi nhu su dung nhien lieu hda thach, pha rirng... san sinh ra mdi nam 6 ty tan carbon. Tinh
toan dien bien nong dp CO2 trong khf quyen theo cac kieh ban khac nhau cho thay ndng dp nay
dat can bang on djnh khoang 500ppmV trong trudng hgp ngay tir bay gid chiing ta khdng lam
gia tang them CO2 va dat gia trj can bang cue doan khoang 1 lOOppm neu tiep tuc phat thai nhu
hien nay (hinh 1). Cac nghien ciiu ve dien bien khi hau cho thay mdi quan he true tiep giua
nong dp CO2 trong khf quyen va su dao dpng ehu ky cua nhiet do trong vdng 150000 gan day.
Neu ndng dp CO2 tang len gap doi se lam gia tang nhiet dp trung binh eua mat dat len 2,8°C.
Dieu nay se lam dao Ion khf hau tren hanh tinh.

1900

2000

2100

2200,,. 2300
i4ata

1900

20<K>

2100

2200,,-

2300

Hinh 1. Tinh toan du bao ndng dp CO2 trong khi quyin vdi cac kjch barilJhac nhau
ve sii dung nang lupng [9]


385

Hcin chi phdt thdi chdt khi gdy hiiu img nhd kinh vdi cdng nghi iing dung
khi sinh hge trin dgng ca dot trong

Sir gia tang nhiet dp khi quyin gin mat dit gay ra nhung hau qua nang ne ddi vdi mdi
trudng. d cac vimg Chau Phi nhiet ddi, Trung My, Nam My, Dong Nam A va Uc cay cdi Idn
nhanh ban va chet sdm hon. Cd chii'ng 20 giong ddng thuc vat bien mat mdi ngay do bien doi
khi hau. Neu mdi trudng tiep tuc bj tae ddng bdi sir khd ban, bao kit thi sir can bang he thdng
sinh thai ciia hanh tinh se bj anh hudng nang ne.
Khi nhiet do hanh tinh tang len, cac vi khuan, vi triing va cac yeu td truyen benh se phat
trien nhanh chdng. Tren thuc te, nguy co benh tat do bien ddi khi hau da dien ra nhting nam
1993-1995 d Trung My sau mgt giai doan nong bat thudng va do am tang. Nam 1993 benh dich
ta phat trien manh d An Dp sau giai doan mua keo dai. Nam 1996 benh viem mang nao da giet
che hang nghin ngudi d Ddng Phi sau thdi ky khd ban kbimg khiep.
Cae nghien ciru cdng bd nam 2005 eho thay cudng dp nhfrng con bao trong 30 nam qua
tang manh nhung sd lugng cac eon bao ed giam di so vdi trirde day. Cac nghien cii'u tren eiing
cho thay sir gia tang cudng do ciia cac tran bao la do nhiet do khi quyen gia tang.

Ngudi ta udc tinh dai duong hap thu tren 80%) nang lugng cap them vao he thdng khf ban.
Su gia tang nhiet dp dai duong khien nude gian nd va lam tang eao mirc nude bien. Cac sd lieu
nghien ciru do ve tinh cung cap cho thay trong the ky 20, muc nude bien da dang cao khoang
vai chuc cm (0,l-0,2m). Rieng trong giai doan 1961 den 2003, mire nude bien da tang
l,8min/nain. Sir gia tang muc nude bien chii yeu la do gian nd nhiet. Anh hudng eiia sir tan
bang d cac cue the hien trong quang thdi gian dai nhieu the ky. Muc nude bien se dang cao tii'
18 den 59cm vao nam 2100 (hinh 2). Nd cd
the dang cao 2m vao nam 2300 [3]. Sir
80
dang cao mire nude bien vai cm khong gay
7 0 .-.
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CGCM1
anh hudng dang ke ddi vdi bd bien da
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nhung nd gay anh hudng nghiem trpng ddi
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vdi ddng hpc biin cat cua cac bai bien
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phang. Trong nhung vimg nay, dang d trang
?n P
thai can bang dpng bgc, su dang cao mirc
on
10 .d
nude bien tao ra kha nang xam thuc manh
va lam djeh chuyen su can bang toan bp ve
u n
Nam
-10
phfa bai bien bj xam thuc va liii dan vao dat 1950 1975 2000 2025 2050
2100
lien. Vi vay sir dang cao mire nude bien gay
anh hudng quan trpng hon nhieu so vdi viec Hinh 2. Du bao dang cao muc nude bien trong the
dich chuyen bd bien ddi vdi chieu eao muc ky 21 theo cac md hinh toan hpa khac nhau [1]
nude tuong ii'ng.
•

-<(3J

..Q

•

Tl

Cac ngudn gay gia tang chieu cao mire nude bien gdm [1]:

- Gian nd nhiet:

0,2-0,4m/C

- Bang tuyet tren niii cao:

0,15-0,37m

- Bang d Greenland:
- Bang d phfa Tay cac cue:
Bang d phfa Ddng cac cue:

7,3in
5m
52in


386

Bin Vdn Ga, Li Minh Tien, Truang Li Bich Trdm, Nguyin Vdn Ddim

Khi bang tuyet tren qua dat tan hoan toan thi mirc nude bien ed the dang len den 65m. Tuy
nhien su tan bang d cac cue keo dai den hang nghin nam ngay ea khi nhiet dp khf quyin da In
djnh. Dua tren ket qua tfnh toan dien bien nhiet dp khf quyen, ngudi ta du bao cac nguy ca gia
tang muc nude bien trong thien nien ky tdi. Nguy eo' muc nude bien dang len 6in la rit cao
trong 1000 nam nua (bang 1). Toan bd dong bang Bac Bd, Nam Bg va duyen hai Mien Truno
ciia nude ta khi do se bj chim ngap trong nude bien (hinh 3).
Bang 1. Nguy co dang eao mue nude bien
Gia tang muc nude
bien so vdi nam 2000

Nguy CO gia tang mire nude bien
Den nam 2100

Din nam 3000

Sau nam 3000

0-lm

Cao

Chae chan

Chae chan

l-2m

Thap den Trung binh

Chae chan

Chae chan

2-6m

Rit thip

Cao

Cao

6-12m

Khdng xay ra

Thap den Trung binh

Trung binh

12-20m

Klidng xay ra

Thap

Thap den Trung binh

20-65m

Khdng xay ra

Rit thap

Thap

Hau qua ciia hien tugng qua dat am dan len den loai ngudi trong the ky 21 duge torn tat
nhu sau:
Giam siit nang suat san xuat
ndng nghiep d viing nhiet ddi

va gan nhiet ddi;
Giam nguon nude trong hau
het eae viing nhiet ddi va gan
nhiet ddi;
Giam lugng nude do tan bang
tuyet;
Gia tang cac hien tugng thdi
tiet circ doan nhu mua Idn,
bao, kho ban anh hudng den
canh tae nong nghiep;
Gia tang kha nang chay rirng
miia khd;
Md rpng eae vimg bi nhiem
benh ta, benh sdt ret;
Lu lilt Idn gia tang do muc
nude bien dang eao va do bien
doi khi hau;
Gia tang tieu thu nang lugng
cho dieu hda khong khi;

1 2 3 5 8 12
20
35
60 80
Do cao so vdi muc nude bien hien nay
Hinh 3. Nguy co chim ngap d khu vuc Ddng Nam A do
su dang eao mue nude bien [10]


Hgn chi phdt thdi chdt khi gdy hiiu img nhd kinh vdi cdng nghi img dung

khi sinh hge trin dgng co ddt trong
2.

387

Cac giai phap han che phat thai CO2

Loai ngudi da thai vao khf quyen 6 Gt (Gt: ti tan) carbon tuong duong moi nam, tuo'ng
duang 1 tan/ngudi/nam. Udc chirng 3 Gt carbon do dai duong bap thu, vi vay can giam di 50%
mue do phat thai chat khf gay hieu irng nha kfnh de khong lam gia tang ndng dp eiia chiing
trong khi quyen, nghTa la mirc thai tren dau ngudi la 500 kg carbon tuong duong moi nam. Tiet
kiem nang lugng, dac biet la nang lugng hda thach la giai phap hiru hieu. Giai phap nay ddi hoi
thay ddi thoi quen vdn ed ciia con ngudi nhu:
Han che di may bay. May bay tam xa phat thai 60 g carbon tiro'ng duo'ng/km/hanh khach.
Mpt hanh khach lien luc dja bang may bay thai vao khdng khi gan 500 kg carbon tirong duong.
Doi vdi may bay tam ngan, mire dp phat thai trung binh 100 g carbon tuong duo'ng/kin/hanh
khach;
Han che toi da sir dung d td. O td phat thai trung binh 100-250 g CO2 tren moi km, nghTa la
30-70 g carbon tuong duong. Sir dung d to 20 000 km mdi nam se thai vao khi quyen 600-1400
kg carbon tuong duo'ng;
Tdi uu hda each nhiet nha d bang kien triic sinh khf bau, sii' dung vat lieu mdi de giam sir
dung nhiet eho he thdng sudi va dieu hda khdng khf.
Mat khac, sir dung cac loai nang lugng tai sinh duge xem la giai phap ben vung. Giai phap
nay mpt mat lam giam phat thai cac chat khf gay hieu irng nha kfnh va mat khac dam bao ngudn
nang lupng thay the ebo nhien lieu boa thach dang ngay cang can kiet dan.
Doi vdi van de phat thai CO2, Viet nam ed muc dp phat thai CO2 tren dau ngudi dan eon
rat thap so vdi mire dp phat thai binh quan ciia the gidi. Nhung thap nien 80, 90 ciia the ky
trude, mirc thai CO2 binh quan dau ngudi ciia nude ta chi bang 1/10 binh quan ciia the gidi.
Hien nay mirc phat thai CO2 binh quan dau ngudi d nude ta xap xi 1/3 mire phat thai binh quan
ciia the gidi [2]. Tuy nhieu dieu quan trpng la toe dp gia tang mirc dp phat thai CO2 eiia nude ta

hien nay rat Idn, trong khi mire dp phat thai binh quan tren the gidi gan nhu dn dinh (binh 4 va
hinh 5).

1950

Hinh 4. Mire thai Carbon binh quan dau ngudi
d Viet Nam [2]

2010

Hinh 5. Mirc thai Carbon binh quan diu ngudi
toan ciu


388

Biti Vdn Ga, Li Minh Tiin, Truong Li Bich Trdm, Nguyin Vdn Ddng

400^
300-

200

N g h i n thiing /ngay

Vdi toe dp gia tang su dung nhien lieu hda thach nhu hien nay trong sinh boat va san xuit
(hinh 6 va hinh 7), trong mpt thdi gian ngan, mirc dp phat thai CO2 tren dau ngudi dan ciia
chiing ta se tang vugt miic binh quan chung cua the gidi. De ban che muc do phat thai CO2 va
dam bao an ninh nang lugng tuong lai, chiing ta can nghien cii'u phat trien cac loai nang lugng
tai sinh. Trong sd cae dang nang lugng nay thi nang lugng tir biomass d nude ta cd tiem nang

rit ddi dao va cd thi khai thac duge bang cac cdng nghe truyen thdng (bang 2). San xuit biogas
til' biomass la giai phap kha thi va thiet thue nhat.

100

nim
1984

1988

1992

1996

2000
2004
Nam

1988

Hinh 6. San xuat dien nang d Viet Nam
(Ngudn EIA International Energy)

1

1

1

1

1

1992

1996

2000

2004

2008

Hinh 7. Tieu thu dau md d Viet Nam
(Ngudn EIA International Energy)

Bang 2. Cac ngudn biomass ciia Viet Nam
STT

Cac chat thai trong san xuat ndng nghiep

Khdi lugng
(trieu tan)

Nang lugng
(GJ)'

3,1

35.960

12,4

186.000

0,015

57

61,9

866.600

Trau

5,6

63.840

6

Than bap

4,8

60.000

7

Than san

0,6

7.500

8

Ba mi'a

1,5

18.750

9

Cac chat ba

5,0

36.050

10

Vo dau

0,1

1.250

11

Vo va la dira

5,8

104.400

12

Vo ea phe

0,3

4.670

101,1

1.385.077

1

Chat thai eua eae nha may eua gd

2

Ciii

3

Chat thai ran do thj (phan ed the chay dugc)

4

Rom ra

5

Tong


389

Hgn che phat thai chat khi gay hieii I'mg nha kinh vai cong nghe I'mg dung
khi sinh hoc tren dpng ca dot trong

Biogas la nang lirgng tai sinh nhan dirge tir qua trinh phan hiiy cac chat hu'u ca trong moi
trirong thieu khong khi. Rac thai sinh hoat, cac chat thai cua qua trinh san xuat nong nghiep,
chan nuoi, xir ly nuoc... la nguon nguyen lieu tot de san xuat biogas. Biogas chi'ra thanh phan
chinh la CHj va cac tap chat nhu' CO2, H2S [4]. De c6 the su dung biogas lam nhien lieu, viec
dau tien la phai loc cac tap chat c6 hai. Tiem nang biogas cua Viet Nam tir chat thai chan nuoi
khoang 2 ty m' (bang 3).
Bang 3. ILoai chat thai

Chat thai
chan nuoi

Chat thai san
xuat nong nghiep

Chat thai cong
nghe thivc pham

Chat thai
sinh hoat

San luong CH4
(mVtan)

25

170

100

80

Neu lay trung binh 200m biogas/tan nguyen lieu va 10% biomass tren day du'gc chuyen
thanh biogas thi moi nam chung ta c6 the san xuat duoc 2 ty m^ biogas. Cong voi 2 ty m^ biogas
san xuat tu chat thai chan nuoi, moi nam chung ta c6 the san xuat dugc 4 ty m^ biogas.
Klio khan trong khai thac biogas de phat dien cua chung ta la nguon nhien lieu khong tap
trung va qui mo khong deu. Nhirng noi c6 san hrgng biogas Ion nhu cac bai chon lap rac, cac
tram xir ly nuoc thai... c6 the su dung dong co ca Ion de keo may phat dien. Cac trai chan nuoi
trung binh va nho, neu sir dung dong ca ca Ion thi khong du biogas de chay lien tuc, neu dCmg
dong ca ca nho thi khong dam bao du'gc cong suat can thiet cho san xuat. Vi vay trong thirc te
hien nay, phan Ian cac ham biogas a nuac ta chi diing de phuc vu cho viec dun nau. O nhCrng
trai chan nuoi chung 50 con heo tra len, krgng biogas sinh ra tra nen du' thua cho nhu cau dun
nau va chung dugc thai ra ngoai khi quyen. CH4 c6 tac dung gay hieu irng nha kinh 23 Ian Ion
han CO2 vi vay viec thai chiing ra khong khi se lam cho moi truong bi 6 nhiem tram trong hon.
Vi vay viec tan dung biogas tir cac nguon khac nhau de san xuat dien nang la rat can thiet de

giam phat thai chat khi gay hieu ung nha kinh va tiet kiem nhien lieu hoa thach a nuoc ta.
Do sir da dang ve qui mo san xuat biogas, de c6 the tan dung dirge nguon biogas phat dien,
cong suat cua dong ca can phai chgn toi uu phii hop qui mo san xuat ciia trang trai va cong suat
cua ham biogas. De thoa man yeu cau do thi dong ca hai nhieu lieu biogas/nhien lieu long mang
tinh thirc te cao hon dong ca chi chay dugc bang biogas [5].
3.

Ky thuat cung cap biogas cho dong co" hai nhien lieu biogas/dau mo

De tao dieu kien thuan Igi cho ngu'o'i dan chuyen doi dong co' sir dung nhien lieu long eo
san sang chay bang biogas, trong cong trinh nay chiing toi che tao cac bg phu kien van nang de
CO the lap dirge tren nhieu kieu dong ca khac nhau. Bg phu kien dugc lap them vao dong ca de
cho phep no chay bSng biogas, khong lam anh huong den hoat dong cir he thdng nhien lieu long
nguyen thuy, vi vay dong ca van co thi chay dirge bang nhien lieu long nhu triroc khi cai tao.
Hinh 8 gioi thieu so do nguyen ly cua he thong cung cap nhien lieu cho dong ca hai nhien
lieu biogas/xang. He thong gom bg dieu toe 1 tac dong d6ng thai len biram ga 2 va van cung
d p biogas 3. Van khong tai 5 kieu mang, ma khi do chan khong sau buam ga du Ion, hut biogas
qua vit chinh khong tai 4. Ti le dp ma buam ga 2 va van con 3 dugc tinh toan sao cho thanh


390

Biti Van Ga, Le Minh Tien, TnangLe Bich Tram, Nguyen Van Dong

ph4n h6n hgp cua dong co dat gia trj toi iru a moi che do cong tac [6]. Bg dieu toe du-gc din
dong nha bull 15p tren banh da dong ca. KJii chay bang biogas, van cung cap xang dugc khoa
lai. Nguge lai, khi chay bSng xang, khoa biogas a vi tri dong.

Biogas

Doi voi dong co' biogas/diesel, he thong cung cap nhien lieu don gian hon vi khong c6
van khong tai 5 va buam ga 2. Dong co' dugc danh Ida bang each phun mot krgng diesel moi toi
thilu (khoang 2-3% lirgng diesel a che do djnh muc). Toe do dong ca dugc gifr on dinh nha bo
dieu toe tac dong len van con cung cap biogas.
Hinh 9 va hinh 10 gioi thieu van dieu toe dong co' biogas/xang va bg dieu toe dong ca
biogas/diesel. Cac van nay diro'c tinh toan cho cac ca cong suat dong ca khac nhau. Ngirai su'
dung CO the lap dat de dang len dong co' chay bang nhien lieu long co san de chay bang biogas
(hinh 11 vahinh 12).

Hinh 9. Van dieu toe dong ca biogas/xang

Hinh 10. Van dieu toe dong ca biogas/diesel


391

Hgn che phat thai chat khi gay hieu i'mg nha kinh vai cong nghe img dung
khi sinh hoc tren dong co dot trong

Hinh 12. Dong co hai nhien lieu biogas/xang

Hinh 11. Dong ca hai nhien lieu biogas/diesel

Dong CO' keo may phat dien bang biogas vai cong nghe nay co nhung tinh nang sau [7]:
- Dugc cai tao ti!r dong ca Diesel hay dong co' xang
- Sau khi cai tao, dong co' van co the chay bang diesel hay bang xang khi can thiet
Tieu thu dau diesel nho hon 3% so vai dinh mire
- Dao dong dien ap nho ho'n 5%o dien ap djnh mire, thai gian qua do nho ho'n 2s
Neu biogas dirge san xuat tir chat thai chan nuoi, thai gian (tinh theo gia) may phat dien
biogas CO the hoat dong lien tuc trong ngay cho a bang 4.

Bang 4. Tirong quan giua cong suat dong ca phat dien va qui mo trang trai chan nuoi
Cong suat
dien (kW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

So lirgng Ign trong trang trai (con)
20

50

100

150

3
1.5

1

8
4
2.5
2

16
8
5
4
3

24
12
8
6
5
4
3.5
3

200

300

16
10
8
6

5
4.5
4
3.5
3

24
16
12
9.5
8
7
6
5.5
4.5
4.3
4
3.5

400

500

21
16
12
10
9
8
7

6.5
6
5.2
5
4.5
4

20
16
13
11
10
9
8
7
6.5
6
5.5
5


392

Biii Van Ga, Le Minh Tien, Truong Le Bich Tram, Nguyen Van Dong

Nha cac bg phu kien tren day, dong ca co the bien Im biogas thanh IkWh dien, tiet kiem
dugc 0,4 lit dau diesel va gop phan lam giam phat thai 1kg CO2 vao bau khi quyen [8].
Theo nhu ph&i tren da trinh bay, tiem nang biggas cua nuac ta co the dat dugc 4 ty
m^/nam. Neu ap dung cong nghe nay de phat dien, moi nam chung ta san xuat dugc 4 ty kWh
dien. NIU cac dong ea tren chay bing dau diesel thi de san xuat dugc krgng dien noi tren chiing

ta cSn din 1,6 ty lit dSu va phat thai vao bau khi quyen 4 ty kg CO2.
Nhu vay, neu sii' dung cong nghe chuyen doi dong ca sir dung nhien lieu long sang chay
bang biogas, mcfi nam chiing ta co the san xuat dugc 10%o nang krgng dien bang nhien lieu thay
the, tiet kiem dugc 15.000 ty dong tien nhien lieu (do cac dong ca chay bang dau), giam phat
thai 4 trieu tan CO2 (tuang duo'ng 1,5 trieu tan C) vao bau khi quyen. Neu so vai mii'e phat thai
C tirong duo'ng eiia nuac ta hien nay la 24 trieu tan/nam thi mire giam nay dat dugc 6,5%.

4. Kit luan
Han che muc do phat thai cac chat khi gay hieu u'ng nha kinh ngay tir bay gia se gop phan
dam bao sir can bang nong do CO2 trong khi quyen a muc thap, tranh dugc nguy ea biing no khi
hau gay hau qua khon luong doi vai su ton vong eiia nhan loai.
Su' dung biogas tir cac chat thai hu'u eo' de chay dong eo' dot trong phat dien thay cho nhien
lieu hoa thach bang cong nghe trong nuac se giiip nuac ta san xuat dugc 10%) dien nang bang
nang lugng tai tao, gop phan lam giam 6,5% phat thai Carbon vao khi quyen.
Tai lieu tham khao
[1] />[2] />[3] />[4] BUI VAN GA, NGO VAN LANH, NGO KIM PHUNG: Purification of biogas for fueling internal
combustion engine. Review Science and Technology, The University of Danang, No 4-2007
[5] BUI VAN GA, LE MINH TIEN, NGUYEN VAN DONG, NGUYEN VAN ANH: He llwng cung
cap biogas cho dong ca dualfuel biogas/diesel. Tap chi Khoa hoc-Cong nghe Dai lioc Da Nang, so
2(25)-2008, pp. 17-22
[6] BUI VAN GA, T R A N VAN QUANG, TRUONG LE BICH TRAM, NGUYEN PHI QUANG; T6i
mt hoa qua trinh cung cap biogas cho dong ca tTnh tai sir dung hai nhien lieu biogas-ddu mo. Tap
chi Khoa hoc-Cong nghe Dai hoc Da Nlng, s6 5(28)-2008, pp. 22-30
[7] BUI VAN GA, TRAN VAN NAM, TRUONG LE BICH TRAM: Engines fueled by biogas: A
contribution to energy saving and climate change mitigation. The 6th Seminar on Environment
Science and Technology Issues Related to Climate Change Mitigation. Japan-Vietnam Core
University Program, Osaka, Japan, 26-28 November 2008
[8] BUI VAN GA, TRAN VAN QUANG, TRUONG LE BICH TRAM: Dong ca link tai chay bhng hai
nhien lieu biogas-diesel. Tap chi Giao Thong Van Tai, pp 23-26, thang 12-2008
[9] http://www,globalwarmingart.com/wiki/Image:Carbon_Stabilization_Scenarios_png

[10] -n/wiki/Image:SE Asia Sea_Level_Risks_png