NG DNG CNG NGH BIOGAS M HNH X L CHT THI TRONG CHN NUI TO NNG LNG
THAY TH THNH PH NNG
BI TIU LUN
I- T VN
Cng ngh kh sinh hc (biogas) c nghin cu v ng dng Vit Nam t nhng
nm 1960. n nay, cng ngh ny lun c ci tin v ng dng rng ri nhng quy m
khc nhau v mang li nhng hiu qu rt ng k trn c bn phng din: kinh t, x
hi, ti nguyn v mi trng. Cng ngh biogas da trn nguyn tc l ln men
trong iu kin ym kh i vi cc cht hu c m ch yu l cht thi sau chn nui v
cht thi ca cc cc l m. Trn nguyn tc , ton b cht thi trong chn nui s
c gom ton b va gii quyt v mt mi trng do hot ng chn nui, sinh khi sn
xut ra kh sinh hc y l ngun nhin liu sch thay th rt hu ch phc v un
nu. thp sngtit kim c khong kinh ph nht nh khi gi nhin liu ang ngy
cng gia tng, cc nhin liu ha thch ang c cnh bo v nguy c cn kit trong
thi gian sp ti. c bit nhng cht cn b sau quy trnh sn xut biogas c s
dng lm phn bn cho cy trng, mang li nng sut cao. Vi v tr thun li, cc
mc tiu pht trin kinh t - x hi v mi trng ca thnh ph Nng trong thi
gian ti, cng ngh biogas cn c ng dng rng ri hn, ci tin hn gii quyt
dt im cc vn nhim mi trng trong khu dn c, vng nng thn v to ra ngun
nng lng thay th phc v ngi dn. II- GII QUYT VN 2.1. Hin trng Thnh ph
Nng, dn s trung bnh n nm 2008 l 822 vn ngi, t l dn c lm nng nghip
thp hn cc tnh thnh khc, din tch t s dng cho nng nghip khong 13.056
ha, gim ng k so vi cc nm trc. Do xu th pht trin ca Nng trong giai
on 2010 - 2020 l pht trin cng nghip khng khi, phn u t mc tiu thnh
ph thn thin mi trng, nn quy hoch chn nui c thc hin t nm 2006, n nay
khu vc chn nui cn li ch yu l huyn Ha Vang. Theo thng k n thi im
thng 10/2008, tng s n gia sc, gia cm trn a bn thnh ph n thng
10/2008 l: 388.073.000 con tng 8,8% so vi cng k nm trc. Hnh thc chn
nui trang tri v ang c chiu hng pht trin. Ton thnh ph c 58 c s chn
nui heo, 22 c s chn nui b, d; 46 c s
chn nui g quy m 200 con tr ln, 03 c s nui ct, 01 c s nui vt .
Tuy nhin, h thng x l cht thi cha hon chnh. Chn nui heo theo phng
thc cng nghip ang tng bc sp xp li, hin trn a bn thnh ph c 5 c s git
m gia sc gia cm tp trung, gm 01 c s ln cng sut 1.000 con/ngy m v 4
c s c qui m nh (cng sut 80 - 100 con/ngy m), hin ang xc tin cc th
tc di di c s git m b tp trung vo ti Khu git m chung hn ch pht sinh
nhim trong khu dn c. Vi quy m nu trn nu khng c qun l v nh hng pht
trin tt th vic pht trin chn nui nh hng n mi trng l khng th trnh khi
trong thi gian ti. Thi gian qua, m hnh biogas ng dng ti Nng t nhng
nm 1980 ch yu l do Trung tm nghin cu ng dng nng lng mi thnh ph Nng
thc hin, vi nhiu vi nhiu quy m khc nhau, nhng a phn l quy m nh h
gia nh vi loi hm biogas c np c nh. y cng l loi hm biogas c B Khoa
hc - Cng ngh chn lm mt trong nhng m hnh chun v c xem l gii php hiu
qu cao trong vic gii quyt nhim mi trng do chn nui nhiu a phng, ng
thi em li ngun cht t cho ngi dn. Tuy nhin, vn nhim mi trng do chn
nui khu dn c th v nng thn thnh ph Nng vn cn din bin rt phc tp. Khi
nhn thc ngi dn c nng ln, sc khe con ngi ang b e da bi nhim mi trng,
th vn mi trng trong chn nui c xi ln. a s cc h chn nui ch yu gia sc,
gia cm c mc thu nhp thp, nhiu h mc ngho. y c xem l ngh chnh yu ca
h, v vy vn mi trng cha c quan tm. Trong khi cng ngh kh sinh hc c ng
dng c hiu qu trong thc tin, nhng mi c trin khai mt vi c s sn xut tp
trung quy m ln, cc d n, chng trnh lng ghp ang tng bc h tr ngi dn
ngho xy dng nhm gim thiu nhim mi trng. Thc t cho thy, quy hoch chn
nui Nng c ch trng t nm 2006 nhng cng ngh biogas cha c ng dng rng
ri, do nhiu nguyn nhn: kinh ph xy dng, nhn thc ca ngi dn, tip cn
thng tin v nhng chnh sch ca nh nc cn thiu. 2.2. S cn thit: Trong bi
cnh hin nay v xu th pht trin trong thi gian ti, cng ngh ny cng c
ngha i vi thc tin Nng l a phng cn phn ln ngi dn sng nng thn v sn
xut nng nghip. Mc d thu hp phm vi chn nui, song nhng nm qua, ngnh
chn nui Nng pht trin kh mnh c v s lng ln quy m, tp trung chn nui
cng ngh cao theo hng tng sn lng.
Cc cht thi chn nui gy nhim ngun nc mt, khng kh, t v nh hng xu n
mi trng sng ca con ngi. Theo tnh ton ca cc chuyn gia trong nc th
hng nm, tng n gia sc, gia cm Vit Nam s thi vo mi trng khong 73 triu
tn cht thi rn. c tnh mt tn phn chung ti vi cch qun l, s dng truyn
thng nh hin nay s pht thi vo khng kh khong 0,24 tn CO2 quy i th vi
khi lng cht thi chn nui nu trn s pht thi vo khng kh 17,52 triu tn
CO2 nu khng c x l. Vic x l cht thi chn nui l mt yu cu cp thit nhm
gim thiu nhim mi trng, nhim ngun nc v ngun dch bnh gy ra cho con
ngi v ng vt... Do vy, vic p dng cc bin php nhm x l cht thi chn nui
l mt trong nhng vn cp bch ca ngnh nng nghip nc ta hin nay ni chung
v Nng ni ring. Mt trong nhng gii php em li a li ch cho ngi chn nui
l cng ngh kh sinh hc. Theo Bo co kho st ngi s dng kh sinh hc nm
2006 do D n thc hin, li ch ca cng trnh kh sinh hc i vi cuc sng ngi
dn c th hin cc mt sau: V kinh t: Kh sinh hc cung cp nng lng sch cho
cc hot ng nh un nu v thp sng thay th loi nhin liu ph bin l in, ci,
rm r, tru, cnh cy kh, than v kh ha lng. Sau khi cc h gia nh ny xy
dng cng trnh kh sinh hc, vic thay th cc loi nhin liu thng dng thay
i kh r rt. C th, s h s dng ci gim 70%, s h s dng than gim 47%, s h
s dng rm, tru, cnh cy kh gim 49% v s h s dng kh ha lng gim 11,5%.
Cn c vo loi, s lng nhin liu c thay th v gi c mua bn th mc tit kim
nhin liu bnh qun i vi mi h gia nh c tnh t 85.000 - 90.000 ng/thng.
c bit, i vi nhng h gia nh s dng kh sinh hc thay th hon ton nhin liu
khc trong vic un nu th tit kim c khong 100.000 ng/thng. Ngoi ra,
vic s dng ph phm kh sinh hc gip gim chi ph mua phn bn cho cy trng.
Chi ph mua phn bn ha hc cho cy trng ca h gia nh sau khi c cng trnh
kh sinh hc gim i ng k (khong t 18 - 30%) so vi trc khi c cng trnh
kh sinh hc. Tuy nhin, khc vi cc loi cy lng thc, rau hoc cy n qu th
hu ht cc h gia nh khng s dng ph phm kh sinh hc bn cho cy cng nghip
v nhng cy cng nghip thng c trng xa nh m vic vn chuyn ph phm kh sinh
hc khng my thun tin. Nhn chung, vic s dng ph phm kh sinh hc khng
nhng tng nng sut cy trng, gp
phn ci thin cht lng sn phm m cn gp phn gim vic s dng cc loi thuc
tr su v phn bn ha hc. V x hi: i vi cc gia nh nng thn, trc khi c cng
trnh kh sinh hc, h dn thng dng ci, rm r, than hoc kh ha lng un nu.
c c nhng nhin liu ny, h dn thng phi i tm kim, nht nhnh hoc tm mua.
Sau khi c cng trnh kh sinh hc, h dn gn nh s dng kh sinh hc thay th
hon ton cho cc nhin liu phc v cho hot ng un nu trc y v tnh trung
bnh, mi h dn c th tit kim 3 - 4 gi/tun cho vic tm kim hoc mua cc
nhin liu. Ngoi ra, vic s dng kh sinh hc trong un nu thun tin v sch
s cng gp phn gii phng ph n v tr em khi gnh nng vt v ca cng vic ni
tr v kim ci, tit kim thi gian cho vic hc tp v ngh ngi. Khi u t xy
dng cng trnh kh sinh hc, thng thng cc h gia nh thng kt hp nng cp
chung tri, khu cng trnh ph, nh v sinh Chnh v th xy dng cng trnh kh
sinh hc trc tip mang li cuc sng tin nghi cho ngi dn nh s dng cht t
c cht lng cao, khu cng trnh ph, chung tri v sinh, sch p v thun tin
nh cuc sng thnh th. V mi trng: Trc khi c cng trnh kh sinh hc th 54%
h gia nh c thi quen phn trc khi bn cho cy trng, 16% h dn bn phn
chung trc tip cho cy v 15% h gia nh trc tip cht thi chn nui ra cng
rnh hoc mng thot nc. Cch gii quyt cht thi vt nui nh trn tc ng xu n
mi trng sng, gy ra mi hi thi quanh khu vc sng v nh hng n nhng h dn
bn cnh. Sau khi c cng trnh kh sinh hc, 72% lng cht thi vt nui c np
vo cng trnh kh sinh hc, 20% h gia nh s dng sau khi phn, 4,8% lng
cht thi vt nui c cc h gia nh bn hoc cho hng xm v ch cn 2,1% lng cht
thi vt nui c thi trc tip vo cng rnh. Nh vy, vic s dng cc cng trnh
kh sinh hc gp phn quan trng gim thiu nhim mi trng do cht thi chn
nui (c tnh x l c 7,5 - 8 triu tn cht thi chn nui). Ph phm kh sinh
hc c s dng lm phn bn cho ng rung v hoa mu c tc dng ci to t, nng cao
ph chng bc mu v xi mn t, gp phn bo v v ci to ngun ti nguyn t canh
tc, gip cho cy trng tng sn lng t 20 - 30%. Thm vo , s dng kh sinh
hc lm cht t nhm gim tiu th g ci phc v cc mc ch khc nhau v cng gp
phn gim cc bnh v mt v phi do khi bi gy ra khi un nu. 2.3. Cng ngh
biogas
Biogas l cng ngh sn xut knh sinh hc, l qu trnh phn rc, phn hu c,
bn cng rnh to ngun kh sinh hc s dng trong h gia nh hay trong sn
xut. Biogas cha thnh phn chnh l CH4 v cc tp cht CO2, H2S v l nng
lng ti sinh nhn c t qu trnh phn hy cc cht hu c trong mi trng thiu
khng kh: rc thi sinh hot, cc cht thi ca qu trnh sn xut nng nghip,
chn nui, x l nc... Sn xut kh sinh hc da trn c s phn hy k kh cc cht
hu c t nhin hay qu trnh ln men metan. Phn ng vt v cc cht thi rn nh
rm r rt thch hp cho ln men k kh. Ngun nguyn liu s dng: cc loi cht
thi gia sc, gia cm hoc bn t ao t, m ly, ph liu, ph thi trong sn xut
nng lm nghip, v cc hot ng sng sn xut v ch bin nng lm sn. Vi sinh vt
thng s dng ngun hu c cacbon nhanh hn s dng nit l khong 30 ln. Do vy
nguyn liu c t l C/N l 30/1 s thch hp nht cho ln men k kh. Trong thc
t, ngi ta thng m bo t l trn. Trong thc t ngi ta thng c gng m bo t l
trn trong khong 20/40. Phn gia sc c t l C/N nm trong gii hn ny nn c
xem l nguyn liu ch yu sn xut biogas.Bng 1- Kh nng cho phn v thnh
phn ha hc ca phn gia sc gia cm:
Vt nui
Kh nng cho phn ca 500kg vt nui Th tch (m 3 ) Trng l n g t i (k
g) 38.5 41.7 28.8 6.78 31.3
Thnh phn ha hc (% khi lng phn ti) Cht tan d ti u Nit Pht pho T l
C / N
B sa B tht Ln Tru Gia cm
0.038 0.038 0.028 --0.028
7.98 9.33 7.02 10.2 16.8
0.38 0.70 0.83 0.31 1.20
0.10 0.02 0.47 ---1.20
20-25 20-25 20-25 ---7-15
Bng 2- nh hng ca loi phn n thnh phn v cht lng kh thu c
Nguyn liu
Sn lng kh m3/kg phn kh
Hm lng CH4
Thi gian ln men (ngy) 10 9 30 20 21
Phn B Phn gia cm Phn G Phn ln Phn ngi
1.11 0.56 0.31 1.02 0.38
57 69 60 68 ---
2.4. Quy trnh sn xut biogas Da vo cc vi khun ym kh, ln men phn
hy k kh, cc cht hu c sinh ra mt hn hp kh, c th chy c: H2, H2S, NH3,
CH4, C2H2trong CH4 l sn phm kh ch yu nn cn gi l qu trnh ln men to
metan. Qu trnh ny c 03 giai on Bin i cht hu c phc stp thnh cht hu c
n gin Hnh thnh acid Hnh thnh kh metan S 03 gian on qu trnh ln
men:Khi vi khun Cht hu c, carbonhydrates, cht bo, protin. H2, CO2,
Acid acetic Acid, propionic, aicd butyric, cc ru khc v cc thnh phn
khc Khi vi khun Khi vi khun
H2, CO2H2, CO2, Acid acetic
Giai on 1:Closdium bipiclobacterium, bacillus gram m khng bo t,
staphy, loccus
Cht hu c phc tp (Prtin, a.amin, lipid)
Cht hu c n gin (Albumoz, pepid, glycerin, a.bo
Giai on 2: Hnh thnh acid (pha acid) Nh vi khun acetogenic
bacteria (vi khun tng hp acetat) cc hydrates cacbon Acid c phn t
lng thp (C2H5COOH, C3H7COOH, CH3COOH pH mi trng di 5 nn gy thi. Cc
vi khun tham gia pha ny: Vi khun Bacillus cereus Bacillus knolkampi
Bacillus megaterium Bacterodies succigense Clostridium carnefectium
Clostridium cellobinharus Clostridium dissolves Thermocellaseum
Pseudomonas Ruminococcus sp Giai on 3: Hnh thnh kh mtan Vi khun
Methanobacterium omelianskii Methanopropionicum Methanoformicum
Methanosochngenii Methanosuboxydan Sn phm c cht CO2, H2, ru bc 1 v
ru bc II A.propionic CO2, H2, A.formic A. acetic Acid (buteric,
valeric, capropionic) CO2, H2, A. acetic, Methanol Sn phm to thnh
A. acetic, A.Lactic A. acetic, A.Lactic A. acetic, A.Lactic A.
acetic, A. sucinic A. acetic, A. formic A.Lactic, Ethanol, CO2 A.
acetic, A. formic A.Lactic, A. sucinic, Ethanol A. acetic,
A.Lactic, A. sucinic, Ethanol, A formic A. acetic, A. sucinic, A.
formic
Methanosarcina barkerli Methanococcusvanirielli Methanorumin
anticum Methanococcusmazei Methanosarcinamethanica Cc phn ng:
H2, A.formic H2, A.formic Acid (acetic, butyric) Acid (acetic,
butyric)
Cao phn t CO2 + H2 + CH3COO- + C2H5COOH + C3H8COOH CH3COO- + H2O
CH4 + HCO3- + Q 4H2 + HCO3- + H2O CH4 + H2O + Q Cc phn ng ch yu xy
ra trong qu trnh ln men ym kh: 4H2 + HCO3- + H+ CH4 + H2O 136
(kalo) T acid formic 4HCOOH CH4 + 3HCO3- + 3H+ HCOOH H2 + CO2 T
acid acetic CH3COO- + H2O CH4 + 3HCO3- (-30 ) T acid propionic
C2H5COO- + 2H2O CH3COO- + 3H2 + CO2 (+ 80) C2H5COO- + 2H2O
7/4CH3COO- + 5/4H2 + 3/2CO2 (- 53) T metanol: 4CH3OH + H2O CH3COO-
+ 3H+ + H2O (- 314) T Etanol: C2H5OH + 3H2O CHCOO- + 5H2 + CO2 + H+
(+ 2) C2H5OH + 3H2O 3/4CH4 + 1/2CO2 + H2O (- 96) T Propanol: C3H7OH
+ 3H2O CH3COO- + 5H2 + CO2 + H+ (+ 84) C3H7OH + 3H2O 9/4CH4 +
3/4CO2 + 5/2H2O (- 118) Cc yu t nh hng n qu trnh ln men:- 130
iu kin k kh: khng c O2 trong dch ln men Nhit : Quy m nh thc hin
30 - 35oC, quy m ln c c kh ha v t ng ha thc hin 50 - 550C. pH: 6,5
- 7,5 (nu nh hn 6,4: vi sinh vt gim sinh trng v pht trin T l
cacbon/nit: t l 30/1 l tt nht T l pha long: T l nc/phn giao ng t
1/1 n 7/1 (t l pha long i vi phn b: 1/1, phn ln: 2/1 ang c ph bin
nht. S c mt ca khng kh v c t: Tuyt i khng c oxy. Cc ion: NH4, Ca,
K, Zn, SO4 nng cao nh hng n sinh trng v pht trin ca vi khun sinh
mtan. Tc b sung nguyn liu: b sung cng nhiu th sn lng kh thu c cng
cao. Khy o mi trng ln men: Tng cng s tip xc c cht Thi gian ln men:
30 60 ngy. 2.5. Mt s ngh:
KT LUN
TI LIU THAM KHO
Bin cht thi thnh in (ANT) - Trong khi gi c bin ng, cng thm ngun
in cung cp khng n nh, nhiu h gia nh ngoi thnh H Ni t ch ra gas t
phn cc loi gia sc, cc loi du ph thi, rc... sau chuyn thnh in nng em
li hiu qu kinh t cao. Vi quy m chn nui khong 20-50 con ln, b tr ln,
vic xy dng cc hm biogas t 5-10m3 khng ch to ra nhng ngun kh gas tt,
m bo cung cp cho h thng bp gas gia nh, cho mt s l si cho gia sc
trong nhng ngy ng thng gi, gn y nhiu a phng, nng dn cn t ch cc my
Demo pht in dng kh gas to thnh in phc v sinh hot, sn xut. Theo
chuyn gia Nguyn Ln Hng: Biogas cha thnh phn chnh l CH4 v cc tp cht
CO2, H2S v l nng lng ti sinh nhn c t qu trnh phn hy cc cht hu c
trong mi trng thiu khng kh: rc thi sinh hot, cc cht thi ca qu trnh
sn xut nng nghip, chn nui, x l nc...
Trong d n nghin cu bin cc ngun cht thi thnh nng lng sch ca Vin
Khoa hc nng lng, mt trang tri chn nui khong 5-7 con b v 30-40 con
ln s lng biogas cung cp cho my pht in 3-5kW hot ng trong ngy.
Nu ngi nng dn mun tn dng ngun kh biogas trong gia nh, cn trang b
my pht in c nh, thm mt b chuyn i s dng nhin liu, t c 1m3 biogas
thnh 1kWh in, tit kim c 0,4 lt du diesel, sau mt nm s dng kh
biogas, ngi dn c th khu hao c tin u t ban u. ng Nguyn Vn Ton, mt k
s c kh qun Long Bin cng my m nghin cu my pht in chy bng biogas cho
bit: Nu khng cn b chuyn i, ch cn thay b ch ha kh ca my v mt s chi
tit cng khng lm nh hng n cu trc my m vn s dng c kh gas, gip ngi nng
dn ngoi thnh chy my bm, h thng ti tiu, h thng nh sng, l si... nu c
iu kin c th chuyn dng in np vo c quy... Vi chi ph 3-5 triu ng cho
cc loi my 1,5-5 kW, ngi nng dn s hon ton yn tm v ch ng ngun nng
lng, nht l nng dn cc vng su, vng xa, gim c 50% chi ph tin in so vi
gi xng du hin nay. ng Nguyn Hu Binh, xm 2 thn Thng, x ng D, Gia Lm
tm s: n S dng nng lng tit kim hiu qu ca Trung tm tit kim nng lng S
Cng thng ti tr cho ti v ng nh Hi Bi, ng Anh kinh ph xy hm, my pht
in chy bng biogas, gip tit kim hng trm nghn ng nhin liu phc v chn
nui cng nh sinh hot gia nh. Tuy nhin vi u t ln, khong 30 triu ng/h
trong khi my pht in li c cng sut thp, th m hnh th im cha hiu qu. V
th, nhn rng gii php s dng nng lng t cht thi trong cc h gia nh chn
nui H Ni, rt cn cc c quan, doanh nghip xc tin h tr b con k thut,
kinh ph xy hm biogas, phng php chuyn i s dng my pht in ng mc ch, ng
cng sut, gip b con gim ti nhim mi trng, tn dng thnh cng cc ngun cht
thi bin thnh gas phc v i sng.
Cng ty t Toyota Vit Nam (TMV) va phi hp cng i hc Nng t chc hi
tho nh gi kt qu trin khai d n th im chuyn i 25 cm my pht in chy bng
biogas c ci to t ng c diesel cho cc trang tri chn nui ti cc tnh min
Bc v min Trung.
D n th im ny nm trong khun kh chng trnh Go Green - Hnh trnh xanh
do TMV phi hp vi B Gio dc&o to v Tng cc Mi trng thc hin.
Ti hi tho, cc nh khoa hc u cho rng, vic ng dng biogas sn xut in
nng quy m nh l rt ph hp vi iu kin nng thn Vit Nam. Vic s dng du m,
kh t, than ... lm gia tng nng cc cht nhim trong bu kh quyn, c bit l
kh CO2, cht kh gy hiu ng nh knh, lm tri t m dn ln. Tm kim v s dng
cc ngun nng lng ti sinh s gp phn gii quyt hai vn ln l mi trng v nng
lng.
Hi tho cng a ra rng, nu cc h chn nui c quy m t 15 - 20 con heo
tr ln s dng biogas chy my pht in c nh s tit kim c khong 24 triu
ng/nm. ng c chy bng biogas c th bin 1m biogas thnh 1kWh in, tit kim
c 0,4 lt diesel v gp phn lm gim pht thi 1kg kh CO2 vo bu kh quyn.
Vic s dng cht thi chn nui to kh ga khng nhng ch ng c ngun in thp
sng duy tr hot ng sn xut, kinh doanh m cn gim nhim mi trng.
D kin, sau khi nh gi hiu qu mt nm thc hin d n th im, TMV s tip
tc trin khai lp t 500 cm my chuyn i ng c chy bng nhin liu diesel
sang chy bng biogas trn quy m ton quc. Dng kh bi--ga chy my pht
in:Li c cho mi trng ln an ninh nng lng27/08/2009 07:03
(HNM) - Tm kim v s dng cc ngun nng lng ti sinh s gp phn gii quyt
2 vn ln ca nhn loi: gim nng cc cht nhim bu kh quyn, c bit l kh CO2
v bo m an ninh nng lng khi ngun nhin liu ha thch trong lng t ngy
cng cn kit. C mt d n ca Trng i hc Nng, nm trong khun kh chng trnh
Go Green - Hnh trnh xanh, gp phn gii quyt bi ton ny: Chuyn i cm my
pht in t ng c diesel sang chy bng kh bi--ga cho 25 trang tri chn
nui. Qua 1 nm th im cho thy, d n khng ch mang li gi tr kinh t m cn
c ngha x hi to ln. Bi--ga khng phi ch un nu
Nhiu nghin cu khoa hc cho thy, tuy hin nay, mc pht thi CO2 bnh
qun u ngi nc ta hin xp x 1/3 mc bnh qun ca th gii song tc gia tng
li rt ln. Theo tnh ton ca nhm nghin cu ca H Nng th vi tc gia tng s
dng nhin liu ha thch trong sinh hot v sn xut nh nhng nm qua, mc pht
thi kh CO2 ca Vit Nam s vt ngng bnh qun chung ca th gii. Cng theo
kt qu nghin cu ny, trong s cc loi nng lng ti sinh nc ta, nng lng t
kh bi--ga c tim nng rt di do, khong 100 triu tn/nm v c th khai thc
a vo s dng c bng cc cng ngh truyn thng.
Gii thiu h thng chuyn i bi--ga ti Cng ty CP Trung Sn.
nhiu ni, phong tro xy hm kh bi--ga phn hy cc cht thi ca qu trnh
sn xut nng nghip, chn nui, rc thi sinh hot pht trin nhng ch yu dng
thay th cht t. C mt thc t l, nhiu trang tri chn nui, cc ch trang
tri u phi dng my pht in v thng b mt in trong khi kh bi--ga c sn
sinh t cht thi chn nui tha un nu. Bi th, h u mong mun c cch no dng
kh ny chy my pht in. Nm bt c mong mun ca nng dn, GSTSKH Bi Vn Ga,
Hiu trng trng H cng cc ng nghip nghin cu v ch to thnh cng b ph kin
vn nng chuyn i ng c tnh chy bng xng du sang chy bng bi--ga/xng hoc
bi--ga/diesel. ng mng hn, chng trnh Go Green - Hnh trnh xanh, mt
chng trnh v bo v mi trng do Cng ty t Toyota Vit Nam phi hp vi B
GD-T v Tng cc Mi trng thc hin ti tr ton b chi ph thc hin th im vic
chuyn i cm my pht in chy bng bi-ga c ci to t ng c diesel cho 25
trang tri trn c nc. Vi s h tr ny, con ng t nghin cu n trin khai ng
dng ngn i rt nhiu v em li li ch c v kinh t, mi trng ln x hi to ln.
Mt m hnh cn c nhn rng Ti hi tho nh gi kt qu 1 nm trin khai d n va c
t chc cui thng 7 ti Nng, c nh khoa hc, nng dn v doanh nghip u nh gi
rng vic ng dng bi--ga sn xut in nng quy m nh l rt ph hp vi iu kin
nng thn nc ta. Ph hp l bi nc ta vn l nc nng nghip, ngun cht thi t
chn nui a dng v phn tn; chi ph xy dng hm bi--ga khng qu cao i vi cc
h chn nui; ch trang tri no mun chuyn hn ng c chy bng diesel sang
chy bng bi--ga c th dng b ph kin GATEC 19, ai mun va dng xng va dng
bi-ga c th s dng b ph kin GATEC 21. Dng kh bi--ga chy my pht in
mang li li ch kinh t c th ong m c. Theo tnh ton ca GS-TSKH Bi Vn
Ga, nu cc h chn nui c quy m t 50 con ln tr ln s dng bi--ga chy my
pht in c nh s tit kim khong 24 triu ng/nm. ng c chy bng bi--ga c th
bin 1m3 bi--ga thnh 1 kWh in, tit kim c 0,4 lt du diesel. Trong khi
, bi--ga c thu hi t cht thi gn nh min ph, c th gip nng dn ch ng c
ngun in s dng cho trang tri, khng ch gim chi ph nhin liu dn n tng
li nhun cho chn nui m cn c th dng ko my cy, chy my gt, vn hnh h
thng ti, thit b bo qun nng sn Nhng khng ch c th, d n ny cn mang li
nhng li ch kh m ong
m. l gim nhim mi trng, gim thiu gy mm bnh cho ngi, gia sc do
ngun cht thi c tn dng ti a v vic s dng ngun nhin liu ti sinh khng
lm tng nng CO2 trong bu kh quyn. Thy r d n ny mang li nhiu li ch
cho x hi, ph hp vi mc tiu "Tr thnh cng dn tt" c t ra t nhng ngy u
thnh lp, TMV h tr ton b chi ph chuyn i cho 25 trang tri. ng Tatsuya
Kijimoto, Ph Gim c Marketing ca Cng ty t Toyota Vit Nam pht biu ti
hi tho: "Chng ti thc s hy vng rng vi vic trin khai thnh cng d n th
im ny, chng ta s gp phn vo vic tn dng ngun nng lng bi--ga mt cch
mnh m nhm tit kim nhin liu ha thch v bo v mi trng. Nhng g chng ta v
ang thc hin phc v cho mc ch chung tay xy dng mt mi trng xanh - sch
- p nhm gn gi bo v cuc sng ca chnh chng ta". Vn V
ng dng cng ngh biogas x l cht thi ti cc khu chn nui tp trungTh
t, 12 Thng 8 2009 07:21 * Ngy 11-8, Hi ng khoa hc xt duyt cng ti ng
dng cng ngh biogas x l cht thi ti cc khu chn nui tp trung ca tnh
Qung Nam do TS. H Tn Quyn lm ch nhim. Mc tiu ca ti nhm xut m hnh ng
dng cng ngh biogas x l cht thi v chy my pht in, vi tng kinh ph l
2,8 t ng. Ngoi ra, m hnh ny i vo ng dng s gp phn gim thiu nhim mi
trng nc v khng kh. a s cc kin phn bin ti hi ng nht tr v ti mang tnh
cp thit, khi p dng vo thc t s gii quyt thu o vn cht thi trong chn
nui tp trung hin nay trn a bn tnh. * ng Phm Thnh Chung, Trng trm
Khuyn nng Khuyn lm in Bn cho bit: Trm va phi hp vi Cng ty TNHH Sn
xut thng mi Quang Huy (vn phng ti H ng - H Ni) trin khai xy dng 5 b
biogas composite. y l m hnh b biogas c lp t bng cng ngh nha
composite v c nhiu u im hn so vi b biogas xy bng gch. Chi ph lp t
mi b biogas t 11-12 triu ng v c nh cung cp thit b ny h tr 1 bp ga,
ng h p lc, 20 mt dy dn ga, n thp sng. Thc ra cng ngh Biogas c t lu
ri, v nguyn tc l ln men trong iu kin ym kh cc cht hu c m y l cht
thi sau chn nui v cht thi ca cc cc l m. Trong cng ngh biogas iu
quan trng l phi ph c vng v b thi phi c thot ra ngoi th hiu qu sinh
kh v x l mi ti u. V d nh 1 trang trai chn nui ln d nh xy 1 b biogas
c th tch l 20M3 v nu nh b ny khng ph c vng, b sau khi phn hy
xong khng thot ra ngoi c th sau khong 2 nm b s y b, vng s dy ln
trn b mt v khi th tch s dng ca b khng cn l 20M3 na nh vy kh nng x l
l rt km v lng kh sinh ra cng khng nhiu do u ra ca b vn cn mi hi thi
ca phn ti. Mt khc b xy sau 1 thi gian s dung vic lin kt gia cc vt
liu s khng bn (gch v va xi mng) do b ngm trong mi trng c tinh axit
v do s gy hi tng rn nt v b s khng kn tuyt i. B xy 1 khi b hng l
khng th s cha c ch cn cch l p b k c ngay khi va xy xong. B xy l
khng th di chuyn c t v tr ny sang v tr khc khi phi chuyn v tr chung
tri chn nui. Khng bit ti nghin cu ca tin s Quyn liu c gii quyt c ht
cc nhc im trn hay khng hay cng ch l b xy nh lu nay dn vn lm? Nu vic
b ra ti 2,8 t ng nghin cu ci lu nay ngi ta lm m khng gii quyt c cc
nhc trm trn th tht l lng ph v ngha qu. Tnh c ti cng c bit b biogas
composite do 1 ngi bn ngoi bc ang dng v gii thiu ti thy n cc k u
vit khng c bt k mt khim khuyt no n hon thin tt c nhng nhc im ca b
xy, ng thi rt ph hp vi cc iu kin chn nui hin nay ca ngi dn k c
trang tri ln, gia tri hoc trong ch nui phm vi h gia nh. Nn chng c s
so snh v la chn ngi dn ca chng c hng li ch nhiu hn vi cng mt s tin
b ra?
ng dng sn xut Biogas t cht thi trong chn nui ti th x Lo Cai ng
dng thnh cng 02 loi m hnh b sinh kh m bo li ch v hiu qu trn 02 mt:
X l cht thi trong chn nui, chng c nhim mi trng. Thu c kh gas lm cht
t phc v sinh hot. Cng ngh xy dng h thng sinh kh thuc 02 loi m hnh c
gi thnh ph hp vi iu kin thu nhp ca s ng h gia nh thuc a bn th x Lo
Cai ni ring v tnh Lo Cai ni chung, c bit l khu vc nng thn. xut nhng
gi php ph bin nhn rng m hnh Biogas.
Th nghim thnh cng, bc u ng dng h thng sinh kh Biogas ti 10 h gia
nh rt ra kt lun. H thng sinh kh Biogas gii quyt c tnh trng nhim mi
trng do chn nui gia sc, gia cm... ng thi to ra c ngun kh t phc v
sinh hot, to ngun phn bn cho nn nng nghip sch. C 2 phng php b xy v
ti nilon to kh sinh hc cn nhn rng ph hp vi iu kin tng h dn c. h
thng Biogas hot ng tt trong tt c cc khu ca qu trnh xy dng - qun l
khai thc s dng, bo dng phi tun th ng tiu chun k thut.
Thu li nhun t cht thi, ti sao khng?Ngy cp nht: 21/05/2009
09:58
nhim mi trng t ngun nc thi lun l vn au u ca cc trang tri chn
nui. Tuy nhin, vi nhng cng ngh ci tin, hin nay, ngi chn nui c th
thu li nhun t ngun nc thi.
Lng gas c sinh ra trong hm biogas (nh chp ti Cng ty TNHH Gia
Nam) Trn tr ca ngi chn nui Hin nay, u t vo lnh vc chn nui gia cm,
gia sc, ngoi ni lo v gi c th trng v k thut chm sc th vn mi trng lun
c ngi chn nui t ln hng u. y cng l vn m chnh quyn a phng rt ch trng
khi quy hoch pht trin chn nui. n c nh huyn Ph Gio c n 7 d n u t chn
nui ln trnh h s xin php n chnh quyn nhng do cha c gii php hu hiu v
vn mi trng nn vn khng c trin khai thc hin. T thc t , nhiu ngi my m
i tm gii php. V gii php tt nht hin nay khng g khc hn l u t hm
biogas ly nhin liu phc v sn xut v x l mi trng. M hnh hm biogas c ng
dng ti cc h chn nui trn a bn tnh Bnh Dng t nm 1992 nhm gii quyt vn
v x l nhim mi trng do cht thi chn nui trn a bn dn c, ng thi to ngun
nng lng in, gas s dng trong sinh hot v sn xut. Tuy nhin, hu ht ch
mang tnh nh l v cn nhiu bt cp v quy trnh, thit k, cht liu s dng v
hiu qu cha p ng c nhu cu ca ngi chn nui. Ph bin trong thi gian qua
l vic ng dng loi hm biogas b tng hoc PE. Tuy nhin, nhc im ca loi hm
ny l dung tch nh, thi gian lu tr ngn nn kh x l cht thi, d h hng, b
lo ha nhanh, kh bo tr sa cha khi c s c v chim nhiu din tch t. Mt kh
khn khc ca ngi chn nui l do khng nm y nhng thng tin v n v t vn,
thit k uy tn nn gp phi nhng trng hp khi b vn u t nhng kt qu mang li
khng nh mong i dn n tm l ngi u t. T m hnh hiu qu T thng 5-2007,
Trung tm ng dng tin b khoa hc v cng ngh tnh trin khai thc hin d n
Xy dng m hnh hm biogas ci tin ly nhin liu chy my pht in cho tri chn
nui gia sc ti Cng ty TNHH Gia Nam, p 9, Long Nguyn, Bn Ct vi quy m
trang tri trn 10.000 con heo, tng vn u t hn 642 triu ng (trong ,
doanh nghip (DN) c h tr 30% ph u t t ngn sch s nghip khoa hc). Sau
18 thng thc hin, kt qu thu hi c vn u t v t sut sinh li cho DN t vic
tit kim nhin liu t n 90%. So snh nhu cu in phc v sn xut ca DN t
ngun in li quc gia l 29,500 Kw/thng. Tnh theo n gi in thi im thc
hin d n l 1,155 th chi ph hng thng DN phi tn km l hn 34 triu ng (nu
tnh theo n gi in hin nay th chi ph ny cn cao hn nhiu). Trong khi ,
t ngun in biogas, DN ch ng c 100% in s dng sn xut, vi 48.000
Kw/thng, tit kim hn 55 triu ng. V ch trong vng 5 nm thc hin d n, li
nhun DN thu c t ngun nc thi chn nui l gn 2,4 t ng. Nh vy, vic ng
dng m hnh ny khng nhng gii quyt c bi ton v mi trng m cn thu c li
nhun t ngun nc thi. Theo ng Trn Vn Khi - Gim c Cng ty C phn Nng lng
v Cng ngh i Hong Kim, s 81, ng D1, KDC Ph Ha I, phng Ph Ha, TX.TDM,
Ch nhim d n nh gi: Ngoi nhng hiu qu v kinh t - x hi, hiu qu v mi
trng cng mang li kt qu phn khi. Theo cc nh khoa hc th nu x l nc thi
qua hm biogas t loi A c th ti s dng trong sn xut. M hnh ny s l c s
ph bin, nhn rng, chuyn giao cng ngh n cc DN chn nui, sn xut, ch
bin. Cng ngh ny cng ng dng hiu qu trong cc lnh vc khc nh ch bin bt
m, ch bin m cao su.... Mi y, trng i hc Tokyo n tham quan m hnh hm
biogas ci tin c ng dng thnh
Biogas - Gii php tit kim nng lng15:0 | 6/11/2006
Trong khi gi xng du lin tc tng v ngun in cung cp lun thiu so vi
nhu cu x hi, vic t ch ra gas t phn cc loi gia sc biogas khng ch c
li v kinh t cho ngi nng dn m cn l mt gii php tit kim nng lng rt hiu
qu cho x hi. Nng dn ch ra in
Gn y, nng dn cc huyn C Chi, Hc Mn, Bnh Chnh, qun 12, G Vp ca
TPHCM r ln phong tro lm biogas t phn chung. Bt k l gia nh chn nui
vi quy m ln (khong 50 con heo, b tr ln) hay gia nh ch chn nui t 5 -
120 con heo cng xy dng hm, ti biogas. L gii hin tng ny, ng Tr Vn
Hu, x Thi M huyn C Chi hn hu ni, trc y, nhng h chn nui lun b t dn
ph gi ln nhc nh v cht thi vt nui gy hi thi khp c vng. Chng ti th
nhiu cch nh xy hm cha phn, thng xuyn lm cng tc v sinh chung tri sch
s... nhng vn khng khc phc c. Trc thc t , nhiu b con nng dn c dp
sang thm, hc tp k thut chn nui nc ngoi v thy h lm hm biogas va x l
c mi hi li mang li hiu qu kinh t ln nn hc tp v em v ng dng ti h chn
nui ca mnh.
S dng ti biogas em li hiu qu cho gia nh ng Trn Vn Thng x Xun Thi
Thng huyn Hc Mn, TPHCM.
Kt qu cho thy, khng nhng mi hi khng cn m cn s dng tr lng gas ln
lm cht t hoc pht in. Ngoi ra, phn hoai (sau khi c ly kh gas) s dng
bn cy trng khng gy mi hi, trnh c rui nhng v c bit bi t th an ton,
khng gy chy l nh phn ti. Gia nh ti c mt hm khng mi 12 khi v mt ti
10m sn xut biogas, vi chi ph u t khong 12 triu ng dng cho vic nu n,
nu ru Trung bnh mi thng tit kim c t 300.000 400.000 tin gas, ng
Hunh Vn Bt, x B im, huyn Hc Mn h hi ni. ng Nguyn Vn Bnh, Ph Ch tch
x Thi M, huyn C Chi cho bit, huyn C Chi c truyn thng chn nui vi quy
m ln, tng n gia sc lun c duy tr trn 4.000 con heo v gn 3.000 con b
nn vic x l cht thi vt nui lun l vn gy au u cho cc cp lnh o huyn. Hu
ht knh rch, ng rung ca huyn hi thi khng chu ni. y th nhng 5 nm tr
li y, nh ph bin v khuyn khch p dng rng ri m hnh lm biogas m v sinh
mi trng trn a bn huyn m bo an ton. Thy c s tin ch trong vic lm
biogas, nhiu ngi dn x Tn Tc, Bnh Chnh, Thi M, Tn Thnh ng, Tn Thnh
Ty, Ph Ha ng r tai nhau cng tm n nhng h gia nh ang s dng biogas tm
hiu v p dng cho gia nh mnh. Ch tnh ring x Thi M, huyn C Chi c gn
200 h dn s dng kh biogas... Khng dng li , kh biogas cn c nhiu ngi
nng dn chuyn qua my Demo to thnh in phc v sinh hot, sn xut. Gia nh
ng Hunh Cng Bng, x B im, huyn Hc Mn l mt in hnh. ng Bng cho bit, tn
dng cht thi hn 100 con heo, gia nh ti lm 2 hm kin c v 1 ti sn xut
biogas. Ngoi ra, gia nh ti mua mt ci my chuyn biogas thnh in thp
sng, phc v cho sinh hot v tri heo c trm con. Nh vy m mi thng gia nh
ti tit kim c 2 triu ng tin in.
B Phm Th Lan - Ph Ch tch Hi Nng dn huyn Hc Mn nhn xt, cch lm ny
va gip ngi dn bo v mi trng, va tit kim in, c bit l nhng phng, x cha
c mng li in quc gia. Pht trin mnh m hnh biomass
ng Hunh Vn Bt, Ch nhim Cu lc b khuyn nng x B im (Hc Mn) nhn mnh,
s d phong tro lm biogas pht trin mnh nhng nm gn y v cc cng on sn
xut biogas n gin, ch cn a phn xung hm (hoc ti), nn phn theo t l 2/3
phn v 1/3 kh, kh theo ng ng dn ln ti tr, t y s a n ni cn s dng. Ngi
dn cng c th t lp t h thng sn xut biogas cho mnh. Tuy nhin, khng t
trng hp cc hm biogas khng cho ra gas v khng m bo ng cc yu cu k thut
nh hm phi tuyt i kn, cn i u vo v u ra cho lng gas nhiu, t t l 2
phn1 kh Trc thc t , b Phan Thu Nga, Trng phng Qun l khoa hc thuc S
Khoa hc v Cng ngh TPHCM cho bit, t nhng nm 90 ca th k trc, s lp
nhiu d n th im trin khai m hnh sn xut kh biogas thay cho gas v in
khu vc ngoi thnh. in hnh nht l ti x Thi M, huyn C Chi. S h tr hn
400 triu ng xy dng nhiu m hnh sn xut biogas th im v tuyn truyn vn
ng ngi dn cng tham gia. Hin cc m hnh trn khng nhng pht trin nhanh
chng trong hot ng sn xut chn nui ca ngi dn trong x, huyn m cn lan
rng ti nhiu tnh, thnh khu vc pha Nam. Cho n nay, gn nh nh no cng t
trang b cho mnh h thng sn xut kh biogas t cht thi vt nui. Trn th
trng hin cng hnh thnh rt nhiu trung tm, cng ty chuyn cung cp dch v
ny. Ch tch Hi Nng dn huyn Hc Mn, ng Nguyn Vn Hu cho bit thm, t nm
2000 n nay, huyn h tr kinh ph l 1,2 triu/h lm ti biogas, k thut cho
ngi dn x Xun Thi Thng. Ring Trung tm V sinh mi trng nng thn u t xy
dng gn 500 h biogas th im cho 8 x thuc 2 huyn Hc Mn v C Chi. Tuy
nhin, theo ng Phan Minh Tn, Gim c S Khoa hc v Cng ngh TPHCM, trong
thi gian ti, ngoi vic khuyn khch b con nng dn duy tr, m rng quy m
sn xut biogas, s s pht trin thm m hnh sn xut biomass. Tc l tn thu
cc loi ph phm nng sn nh tru, rm r... sn xut in. D n ny c Trng i hc
Tokyo Nht Bn ti tr v d kin s sn xut th nghim vo cui nm nay. iu ny
thc s ngha khi trong thi im ny, gi gas ang tng v nguy c thiu in vn
l vn nng trong nhng nm tip theo. (Theo SGGP Online)Cc tin khc Trc
nguy c thiu in : Nhiu gii php tit kim kh thi Tit kim nng lng cho
doanh nghip :: Gii php n gin nht Thay i nh, tit kim ln Biogas - Gii
php tit kim nng lng Lm th no tit kim in cho my ht bi Tit kim in cho
ng c v my bm
1.Gii thiu: Hin nay tnh hnh nhim mi trng din bit ht sc phc tp:
nhim ngun nc, nhim khng kh, Mt trong nhng nguyn nhn dn n nhim l do:
rc thi, nc thi t cc khu cng nghip hay cht thi v nc thi t cc khu chn
nui, v nc v cht thi sinh hat gia nh thi ra. gii quyt mt phn nhim mi
trng trn th vn s dng cng ngh Biogas l ht sc cn thit trong tnh hnh
hin nay. Mt mt n gii quyt vn nc thi v cht thi t cc khu cng nghip v
cc khu chn nui; hay cc cht thi v nc thi sinh hat gia nh gy nhim, mt
khc cc hp cht ny trong iu kin nng m s b phn ha nhanh sinh ra nng
lng v cc cht hu c phn t nh hn hoc cc cht v c, y l ngun nng lng ti
sinh hu ch m con ngi s dng n mang li hiu qu kinh t t Gas thu c lm
cht t hay chy my pht in thay th ngun in cn thiu ht hin nay, ng thi
n cn to cc cht dinh dng d hp thu hn cho cy trng v vt nui. 2. To
Biogas: c nhiu cch to Biogas nhm gii quyt vn mi trng v to gas s
dng. S lng v cht lng cht thi chn nui ph thuc vo n gia sc, theo TS
Nguyn Dng Khang th tru, b: mt ngy lng phn thi ra l 14kg/con; heo
2,5kg/con. Lng kh sinh ra tru b 260-280 m3/tn phn; heo 561m3/tn
phn, nh vy nu bit tn dng ngun nng lng ny s gim c mt lng chi ph ng k
trong vic nhp khu xng du ca c nc, gim p lc cho nn kinh t ng thi c
th ch ng c ngun nng lng.
Tnh trng nng lng ngy cng khan him trn th gii, c bit l cc loi nng
lng ho thch (fossil fuels) nh du kh v than . Hin nay, gi du th bc
qua ngng ca 90 M kim v c nhiu ch du s tng ln 100 M kim trong mt tng
lai khng xa cng nh tr lng du c c tnh s cn kit vo nm 2050. Tng t, cc
m than cng ang c khai thc ti a tng theo nhu cu nng lng ca cc nc trn
th gii c bit l Trung Quc v n . Trung Quc hin ti l mt nc tiu th du
ho ng th hai trn th gii, ch sau Hoa K vi mc tiu th trn 16 triu thng
du mt ngy. Trc tnh trng trn, t hn 20 nm qua, nhiu nh khoa hc trn th
gii bt u truy tm loi nng lng khc nht l cc loi nng lng ti lp
(renewables). Bi vit ny tp trung vo mt loi nng lng gn gi vi chng ta
nht, l nng lng c c t rc hu c t gia nh v phn chung ca gia sc nh tru,
b nga vn vn Theo nh ngha biogas hay kh sinh hc l hn hp kh methane v
mt s kh khc pht sinh t s phn hu cc vt cht hu c. Methane cng l mt kh
to ra nh hng nh knh gp 21 ln hn kh carbonic. Theo c tnh ca B Nng
lng Hoa K, nu s dng tt c ngun nguyn liu c th to ra kh sinh hc dng
trong vn chuyn th lng nng lng ny c th lm gim 500 triu tn kh
carbonic hng nm, tng ng vi vi s lng 90 triu xe dng trong mt nm. Nng
lng Biogas Biogas c xem nh l mt loi nng lng sinh hc c c t s nn hoc
kh (digestion) hay ln men (fermentation) trong iu kin ym kh
(anaerobic) ca nhng vt cht c ngun gc hu c nh phn chung, bn (sludge)
trong h thng cng rnh), rc ph thi gia c, hoc cc loi rc hu c c th b
sinh phn hu (biodegradable waste). Cc biogas chnh yu trong nhng iu
kin k trn gm kh methane v kh carbonic (CO2) v mt s kh thi khc nh
nitrogen (N2), Hydrogen (H2), hydrogen sulphide (H2S) v oxygen
(O2). Tu theo ngun gc pht sinh ra kh , nhng loi nng lng sinh hc c
nhiu tn khc nhau nh: kh m t (swamp gas), kh m t cy c (marsh gas),
kh bi rc (landfill gas), v kh nn (digester gas).
Trong tt c kh pht thi qua phng php nn ym kh (anaerobic
digestion), methane l kh hu dng nht , l mt loi nng lng ti to cho
vic chy xe, hay chy my pht in. Methane cn dng trong vic nu n, t l
si, lm n , hay to ra sc nng v.v
Sau y l vi s liu v mc sn xut kh biogas. 22 quc gia trong Lin Hip
u Chu (EU) nm 2006 sn xut 62.000 GWh, trong 32.000 GWh n t kh bi rc
v 11.000 n t kh m t t bn trong h thng cng rnh. C 17.000 GWh c hon
chuyn thnh in nng. c l quc gia sn xut biogas nhiu nht vi 22.000
GWh.
Ti Hoa K, lng biogas sn xut chim 6% kh t thin nhin s dng cho ton
quc vo nm 2006, tng ng 10 t Gallons xng. Ngy 4/8/2007 va qua quc hi
Hoa K mi va mang d lut Khuyn khch sn xut kh sinh hc 2007 (Biogas
Production Incentive Act 2007) nhm mc ch: 1- dng qu d tr nng nghip
tr cho nh sn xut kh sinh hc trc nm 2013; 2- to iu kin thun li cho
vic vay n u t, tr cp cho nhng nh sn xut miT y, d lut mt khi thnh
lut s khuyn khch nng dn y mnh cc d n bin ph thi thnh kh sinh hc,
gim thim mt s lng khng nh trong vic s dng nng lng v hn ch s hm nng
ton cu qua vic gim thim kh carbonic thi hi vo khng kh.
Phng php nn k kh
Nh ni trn, y l mt phng php da theo nguyn tc phn hu sinh hc ca
nhng vt cht hu c trong iu kin khng c khng kh. Do h thng nn ym kh c
ch to kh tt c ph thi hu c, bn hu c, cng phn chung cho ra kh methane
v mt s kh khc. Tu theo nguyn liu s dng (ph thi) kh methane thu hoch
c chim khong t 50 n 75% tng lng kh hnh thnh, kh carbonic chim
25-50%, Nitrogen 0-10%, Hydrogen 01%, Hydrogen sulphide 0-3%, v
Oxygen 0-2%. Kh sinh hc t phn chung cho 65% kh methane, l cy kh cho
58%, v l cy ti c 70% methane.
Lng kh sinh hc sn xut tu theo nguyn u ca ph thi v phng php ln
men, iu kin nhit , cc chng loi l kh ym kh, v thi gian phn ng
(retention time). iu kin ti u cho mc sn xut kh l nhit 33oC v thi
gian phn ng l 100 ngy. Th d: 1 Kg phn chung (b, nga, tru) cho c 15
lt kh sinh hc trong thi gian phn ng 30 ngy di nhit 20oC. Nu thi
gian phn ng ko di ln 100 ngy di nhit 33oC, lng phn ny s cho 54 lt
kh sinh hc.
Li im trong vic sn xut kh sinh hc
Vic sn xut kh sinh hc to ra rt nhiu thun li cho ngi dn nht l nng
dn, gii quyt c mt s vn nng lng cho a phng v ngay c trn bnh din quc
gia, chnh quyn trung ng c th qun bnh c cn cn phn phi v qun bnh nng
lng v gim thiu c ngoi t do nhp cng xng du. Do , hai lnh vc mi trng
v kinh t gt hi c nhiu phc li nht.
Ti Hoa k tnh n nm 2006 c 380 bi rc ln c h thng thu hi kh methane
v chuyn ti thnh in nng. Trong vi nm ti c tnh c n 700 bi rc s lp t h
thng ny. Mt th d in hnh ti Irvine, CA kh methane t bi rc Bowerman s
c dng lm nguyn liu cho h thng chuyn ch cng cng cho thnh ph.
V li ch mi trng, kh methane sinh hoc (biomethane) l mt loi nng
lng sch nht tnh n ngy hm nay. Nu methane khng c thu hi t cc bi rc,
cc m (lagoons) ph thi v.v s l mt ngun nhim nh hng n hiu ng nh knh
nhiu nht. Nu dng methane thay th cc loi nng lng ho thch c c nhiu li
im v phng thch cc loi kh thi t hn khi s dng. V mt li ch khng nh cho
mi trng na l, h thng sinh kh s gii to c din tch ph thi v to thm
ngun thu nhp mi cho nng dn.
ng v phng din kinh t, kh sinh hc ngy cng tng trng s gip cho nhu
cu s dng nng lng trong nc n nh hn v ln ln thay th mt s lng khng nh
cc loi nng lng ho thch ang dng. K thut sn xut khng phc tp do c th
tri rng khp nng thn. c bit nng dn c th dng ngun kh sinh hc trong
phm vi gia nh c c c lp v kh t v ph phm ca vic chuyn i phn chung
thnh kh s l mt ngun phn bn hu c rt thch hp trong vic trng ta. Kt
lun Ngy nay, i vi cc quc gia ang pht trin trong c Vit Nam, kh t hin
vn ang l mt kh khn cho chnh quyn trong vic phn phi n nhng vng su v
xa. V vy pht trin k thut to ra kh sinh hc t phn chung qua h thng nn
ym kh s gip cho nng dn t tc c nhu cu nng lng ny. Vn c t ra l chnh
quyn cn hng dn k thut l lm th no che knh hm phn hay cc h phn
(lagoon) i vi phn lng v y l mt phn ng sinh phn hu trong iu kin khng
c khng kh.
Tin thm ln mt bc na, i vi nhng vng c chn nui k ngh, a phng hay
trung
ng cn gip ti chnh ban u thit lp h thng nn k kh c quy m nh mt nh
my. T sinh kh methane s c phn phi n tn nh nh thnh ph.
Ring ti Vit Nam, k ngh phn chung hay lp t h thng thu hi kh hu nh
cn trong tnh trng phi thai v cha c ph bin, do , y l mt tht thot ln
i vi ngun nng lng ny. Thm na, trong k ngh sn xut ru cn (alcohol)
qua quy trnh ln men ym kh cho ra mt s lng ln kh methane nhng cng
khng c thu hi. mt nh my sn xut cn ti Si Gn vi cng sut 20.000
lt/ngy, lng sinh kh pht thi c c tnh khong 10.600 m3 phng thch vo
khng kh, lm nhim mi trng v ph phm mt ngun nng lng khng nh. Mi mt
khi sinh kh sinh ra 5.300 Kcal, hay nh my c kh nng sn xut 56 triu
Kcal/ngy, tng ng vi vic s dng 7,4 tn du FO dng t l hi. Nu Vit Nam
bit tn dng v khai trin ngun nng lng sinh kh biogas, Vit Nam s khng
cn l thuc nhiu vo ngun nng lng ha thch nh du ho v than nh hin nay
trong khi nhu cu ngy cng tng theo pht trin quc gia. West Covina,
11/2007
Pht in t cht thi chn nuiTrong thi bui xng du ln gi, vic bin cht
thi trong chn nui thnh nguyn liu chy my pht in l mt sng kin ng trn
trng. ng qu hn, tc gi ca sng kin ny l mt ngi nng dn t hc.n thm
trang tri chn nui heo ca anh nng dn Nguyn Vn Dc x Giang in, huyn
Trng Bom, tnh ng Nai, vi quy m trn 1.000 con heo, chng ti hon ton
khng pht hin ra mi hi thi, v cnh quan mi trng chung quanh sch p. l
nh tng sng to ca anh, s dng cng ngh biogas ng b tng khi lm nhim mi
trng ng thi lm li nhiu ngun nh s dng kh sinh hc thp sng v chy my.
Mt gii php hu ch cho rung vn trang tri. T thc v nhim mi trng Mt vn
nn thng xuyn phi i mt vi cc tri chn nui heo c quy m ln l tnh trng
nhim khng kh. Mi hi thi ca phn, nc thi thng xuyn gy phin h, e do sc
kho cho nhng ngi sng chung quanh khu vc chn nui. Anh nng dn Dc c
thc chng li s nhim mi trng t nhng nm 2003. Anh t hc hi thit k h
thng ng b tng, ng nha composite nhm "khng ch" mi v khng cho kh bn
thot ra ngoi. H thng ng thot ny c chn su di t theo phng chm chung
tri thong m, chm sc v qun l k thut tt, mi trng sch s khng hi thi
rui nhng, lun ci thin n ging cho nng sut v cht lng cao, n nh nhm p
ng yu cu ca ngi tiu dng.
Nng dn Nguyn Vn Dc
T nm 2003, anh Dc x l thnh cng vic nhim mi trng, trang tri heo
sch s, thong mt... Anh t hc hi t sch v, thc t tham quan. Bng kinh
nghim, anh thit k v xy dng m hnh hm biogas ph bt c nhiu u im nh gi
thnh thp, cho kh CH4 nhiu, cht lng gas n nh, p sut iu ho nn chy my
rt tt c bit l khc phc c tnh trng nhim khng kh. T khi s dng kh
biogas cho thp sng ton trang tri, anh tit kim c chi ph v in v cht t
rt nhiu. i ln tht bi... Ti trang tri ca anh hin c 3 ng c dng ko my
pht in dng cho sinh hot v my nghin thc n gia sc. Hin ti trang tri
heo c xy dng mt hm biogas c sc cha khong 15m3 v thng qua h thng nc
thi ca tri heo, kh gas c lc tch hi nc qua h thng lu tr bng ti nylon
c dung tch khong 20m3. C h thng ny x l c cht thi cho khong 100 con
heo. H thng ng dn gas c ni vo mt ng c lm nhin liu vn hnh, ng c ny c
u ni trc tip vo mt my pht in vi cng sut 10kW in p 220V dng cho in
sinh hot gia nh, chn nui nh thp sng, chy my nghin thc n gia sc, bm
nc, nu n v.v... Vi lng kh biogas sinh ra trong h thng hm cha nh
trn, chy mt Heo ni, ngun cung cp biogas ng c c cng sut 10kW cung cp
c lng in tiu dng cho khong 4 ting ng h mi ngy. ng c chy bng kh
biogas ca anh c s dng t mt ng c xng ca xe hi, ch ci to li b ch ho
kh iu chnh lng nhin liu cho ph hp bng mt mch in t iu khin lng nhin
liu (tng, gim gas) t ng cho ph hp vi qu trnh tng ti hoc gim ti ca
ng c. Mt bnh c quy dng khi ng ng c, ng x hm thanh nhm gim ting n, b
truyn ti t ng c n my pht in 10kW v cc thit b iu khin khc. Anh Dc tm
s: "Ti tht bi trn nm ln khi s dng kh biogas chy my pht in. Ln u tin
ti tht bi l gp s c do b ch ho kh mua t cc ng c xe hi c loi v lp rp.
ng c ci th xng, ci th du v.v... v khng ng b nh vy nn chy mt thi
gian ngn my li ngng, phi np li nhiu ln my chy ri li ngt... Va hi bu
gi va hao gas". Mt my pht in 10kW do anh ch to bao gm thit b v cng
lp t bo hnh 6 thng c gi tr 14 triu ng. So vi gi thnh cng loi trn th
trng, y l mt gi hp dn, c sc cnh tranh v d chuyn giao cng ngh biogas
ng b tng cho cc trang tri chn nui. Ngoi ra, my pht in ca anh cn c
nhiu ci tin hn so vi cc my trn th trng nh c cn dch chuyn, c tnh c
ng, c th thay th cc chc nng khc, d bo tr, cng sut my a dng c th ko
my pht in t 2 2,5kW, 5kW, 10kW nhm p ng ph hp vi quy m ca tng hm
sinh kh biogas. Khi c hi v ln tht bi th nm, anh cho bit: "Cc my xe
hi 4 th chy bng xng, du rt a dng, nhiu kiu dng, nhiu hng khc
nhau... Do khi "my m" lp rp xong, ng c khng ng b nn khng chu "hp
tc" trong khi th trng li khng c ph kin ph hp. Tht bi nhiu ln, sau
ti ny ra t o, v v nh cc c s in t gia cng ring cc bng mch in t ca
mnh theo thit k k thut... sau lp rp ng b my mi chu chy".
M hnh hm biogas
Mt m c rt... i thng Anh Dc qu Qung Ngi, vo ng Nai t 1980 lp
nghip x Giang in, sn xut theo m hnh trang tri chn nui kt hp trng
trt nng sut cao. Anh c bnh chn l m hnh nng dn sn xut gii nm 2007.
Anh c 3 con, mt con gi tt nghip i hc Qun tr kinh doanh hin ang lm
vic ti TP. HCM, mt con trai ang du hc ti c, mt con trai ang hc ph
thng trung hc v mt m gi 83 tui ang sng chung vi anh. Hin nay, anh
Dc ang tham gia sinh hot ti Hi nng dn x Giang in, ng Nai. Anh tm s:
"Ti c mt c mun duy nht l lm sao c vn tip tc tm ti ch to ra h thng
lc kh biogas My pht in thnh kh sch khng gy hi cho mi trng v sc kho.
Theo ti bit trong biogas c cha nhiu kh nh CH4, H2S, CO, SO2, NO,
O2, SO, H2... c bit, kh SO2 khng mu v c mi trng thi, l loi kh rt c.
Ti rt mong mun cc nh khoa hc ng hnh cng tng gip ti". C mt thc t l
hin nay vn cha c c s no nh gi bn v tnh n nh ca nhng chic my pht in
t chy bng xng sang kh biogas ny nh an ton, qu trnh t nhin liu c chy
ht hay khng, cc tp cht trong kh c c lc sch hay khng... V vy, thit
ngh cn nn c s nh gi ca cc c quan chc nng, nu xt thy t yu cu k thut
th c th h tr nhn rng m hnh ny trong b con nng dn.
2.1.5. Cht thi rn (Solid waste): cc cht thi rn ni a l mt vn chnh
trong x hi tiu dng ca chng ta. Vic loi b chng c theo di thng xuyn
bi lin quan n nhim nc ngm v khng kh. Tuy nhin, chng bao gm mt phn
ln l cc cht hu c d phn hu sinh hc. V vy, ngun c phn bit l cht thi
sinh hc c th c chuyn thnh mt ngun ti nguyn c gi tr bi vic v phn gii
k kh. Trong nhng nm gn y, qu trnh ny c nhng bc pht trin ng ghi nhn
v c thit k v iu chnh qu trnh. C th l, s phn gii k kh cc cht thi rn
trong cc b phn gii k kh tc cao t c s chp nhn ngy cng tng ca cng
chng bi n cho php phc hi mt s lng ln kh sinh hc c gi tr cao cng vi
cc cn b hu c n nh c cht lng cao v iu ny khng lm tng s kh chu cho mi
trng. Hn th na, s phn gii k kh ca cc cht thi rn hn hp ang c tp
trung pht trin bi v trong tng lai gn, n c th l mt bc quan trng
trong vng tun hon ca cht thi rn v l mt gii php c chn la cho s phn
hu rc.
A LI CH CA CNG NGH KH SINH HCTHS. L THOA VN PHNG D N KH SINH HC
- B NN&PTNT Vit Nam l mt nc nng nghip vi khong 80% dn s sng vng
nng thn. Sn xut nng nghip ng vai tr rt quan trng trong nn kinh t nc
ta. Nhng nm qua, ngnh chn nui pht trin kh mnh c v s lng ln quy m.
Tuy nhin, vic chn nui thiu quy hoch, c bit cc vng dn c ng c gy ra s
nhim mi trng ngy cng trm trng. Cc cht thi chn nui gy nhim ngun nc
mt, khng kh, t v nh hng xu n mi trng sng ca con ngi. Theo tnh ton
ca cc chuyn gia trong nc th hng nm, tng n gia sc, gia cm Vit Nam s
thi vo mi trng khong 73 triu tn cht thi rn. c tnh mt tn phn chung
ti vi cch qun l, s dng truyn thng nh hin nay s pht thi vo khng kh
khong 0,24 tn CO2 quy i th vi khi lng cht thi chn nui nu trn s pht
thi vo khng kh 17,52 triu tn CO2 nu khng c x l. Vic x l cht thi chn
nui l mt yu cu cp thit nhm gim thiu nhim mi trng, nhim ngun nc v
ngun dch bnh gy ra cho con ngi v ng vt... Do vy, vic p dng cc bin
php nhm x l cht thi chn nui l mt trong nhng vn cp bch ca ngnh nng
nghip nc ta hin nay. Mt trong nhng gii php em li a li ch cho ngi
chn nui l cng ngh kh sinh hc. Cng ngh kh sinh hc c nghin cu v ng
dng Vit Nam t nhng nm 1960. K t , cng ngh ny lun c ci tin v ng dng
rng ri nhng quy m khc nhau. Cng ngh ny v ang em li nhng hiu qu ng
mng v kinh t - x hi v mi trng cho ngi dn. Vi nhng li ch m cng ngh
ny mang li, d n Chng trnh kh sinh hc cho ngnh chn nui Vit Nam, giai
on 2007 - 2011 c xy dng vi mc tiu pht trin ngnh kh sinh hc bn vng
theo hng th trng v gim s dng nhin liu ha thch. D n do Cc Chn nui (B
Nng nghip v Pht trin nng thn) v T chc Pht trin H Lan Vit Nam
(SNV-VN) thc hin. Theo Bo co kho st ngi s dng kh sinh hc nm 2006 do
D n thc hin, li ch ca cng trnh kh sinh hc i vi cuc sng ngi dn c th
hin cc mt sau: V kinh t: Kh sinh hc cung cp nng lng sch cho cc hot
ng nh un nu v thp sng. Trc khi c cng trnh kh sinh hc, hu ht cc h
gia nh u s dng loi nhin liu ph bin l in, ci, rm r, tru, cnh cy kh,
than v kh ha lng. Sau khi cc h gia nh ny xy dng cng trnh kh sinh
hc, vic thay th cc loi nhin liu thng dng thay i kh r rt. C th, s h
s dng ci gim 70%, s h s dng than gim 47%, s h s dng rm, tru, cnh cy
kh gim 49% v s h s dng kh ha lng gim 11,5%. Cn c vo loi, s lng nhin
liu c thay th v gi c mua bn th mc tit kim nhin liu bnh qun i vi mi
h gia nh c tnh t 85.000 - 90.000 ng/thng. c bit, i vi nhng h gia nh
s dng kh sinh hc thay th hon ton nhin liu khc trong vic un nu th
tit kim c khong 100.000 ng/thng. Bn cnh , vic s dng ph phm kh sinh
hc gip gim chi ph mua phn bn cho cy trng. Chi ph mua phn bn ha hc
cho cy trng ca h gia nh sau khi c cng trnh kh sinh hc gim i ng k
(khong t 18 - 30%) so vi trc khi c cng trnh kh sinh hc. Tuy
nhin,
khc vi cc loi cy lng thc, rau hoc cy n qu th hu ht cc h gia nh
khng s dng ph phm kh sinh hc bn cho cy cng nghip v nhng cy cng
nghip thng c trng xa nh m vic vn chuyn ph phm kh sinh hc khng my
thun tin. Nhn chung, vic s dng ph phm kh sinh hc khng nhng tng nng
sut cy trng, gp phn ci thin cht lng sn phm m cn gp phn gim vic s
dng cc loi thuc tr su v phn bn ha hc. V x hi: i vi cc gia nh nng
thn, trc khi c cng trnh kh sinh hc, h dn thng dng ci, rm r, than
hoc kh ha lng un nu. c c nhng nhin liu ny, h dn thng phi i tm kim,
nht nhnh hoc tm mua. Sau khi c cng trnh kh sinh hc, h dn gn nh s
dng kh sinh hc thay th hon ton cho cc nhin liu phc v cho hot ng un
nu trc y v tnh trung bnh, mi h dn c th tit kim 3 - 4 gi/tun cho vic
tm kim hoc mua cc nhin liu. Ngoi ra, vic s dng kh sinh hc trong un
nu thun tin v sch s cng gp phn gii phng ph n v tr em khi gnh nng vt
v ca cng vic ni tr v kim ci, tit kim thi gian cho vic hc tp v ngh
ngi. Bn cnh , khi u t xy dng cng trnh kh sinh hc, thng thng cc h
gia nh thng kt hp nng cp chung tri, khu cng trnh ph, nh v sinh Chnh
v th xy dng cng trnh kh sinh hc trc tip mang li cuc sng tin nghi
cho ngi dn nh s dng cht t c cht lng cao, khu cng trnh ph, chung tri
v sinh, sch p v thun tin nh cuc sng thnh th. V mi trng: Trc khi c
cng trnh kh sinh hc th 54% h gia nh c thi quen phn trc khi bn cho
cy trng, 16% h dn bn phn chung trc tip cho cy v 15% h gia nh trc
tip cht thi chn nui ra cng rnh hoc mng thot nc. Cch gii quyt cht
thi vt nui nh trn tc ng xu n mi trng sng, gy ra mi hi thi quanh khu
vc sng v nh hng n nhng h dn bn cnh. Sau khi c cng trnh kh sinh hc,
72% lng cht thi vt nui c np vo cng trnh kh sinh hc, 20% h gia nh s
dng sau khi phn, 4,8% lng cht thi vt nui c cc h gia nh bn hoc cho
hng xm v ch cn 2,1% lng cht thi vt nui c thi trc tip vo cng rnh. Tm
li, vic s dng cc cng trnh kh sinh hc gp phn quan trng gim thiu nhim
mi trng do cht thi chn nui (c tnh x l c 7,5 - 8 triu tn cht thi chn
nui). Ph phm kh sinh hc c s dng lm phn bn cho ng rung v hoa mu c tc
dng ci to t, nng cao ph chng bc mu v xi mn t, gp phn bo v v ci to
ngun ti nguyn t canh tc, gip cho cy trng tng sn lng t 20 - 30%. Thm
vo , s dng kh sinh hc lm cht t nhm gim tiu th g ci phc v cc mc ch
khc nhau v cng gp phn gim cc bnh v mt v phi do khi bi gy ra khi un
nu. Thc t trin khai D n t giai on I (2003 - 2005) chng minh rng,
cng ngh kh sinh hc l mt cng ngh thch hp cho gii php x l cht thi chn
nui nc ta hin nay v mang li a li ch cho ngi dn. iu kin cho cc h dn
tham gia d n kh n gin, th tc
thun li v d dng. Cc h gia nh nu nui t 6 u ln tr ln (hoc mt con
ln ni; hai con tru, b) u c th ng k vi cn b ca d n (thng l khuyn nng
vin ca x) c t vn v tin hnh k hp ng xy dng cng trnh. Vi gi vt liu xy
dng ti thi im ny, chi ph cho mi cng trnh kh sinh hc trung bnh 10 m3
khong 6 - 8 triu ng. Khi tham gia d n, ngi dn khng nhng c hng li t
nhng li ch m cng trnh kh sinh hc mang li m cn c th nhn c s h tr v
ti chnh v k thut ca d n nh: - Trc khi xy dng cng trnh kh sinh hc,
cn b d n s kho st thc t v t vn cho h dn la chn kiu loi cng trnh sao
cho ph hp vi iu kin, mc ch s dng v quy m chn nui ca gia nh. - Trong
qu trnh xy dng, h dn s c cung cp bn v k thut ca cng trnh. Trong bn
v ny, cc thng s ca cng trnh c tnh ton mt cch ti u da trn phn mm my
tnh gip cho cng trnh hot ng mt cch hiu qu. i ng th xy ca D n l nhng
ngi trc tip xy dng v lp t thit b kh sinh hc cho h dn. Cc i th xy ny
u l th xy lnh ngh v c tham gia o to v k thut xy dng cng trnh kh
sinh hc do D n t chc v cp chng ch. Hn na k thut vin huyn v tnh lun
sn sng h tr gim st k thut khi cn thit v l ngi kim tra cht lng,
nghim thu cng trnh m bo cng trnh c xy dng ng thit k. Do vy, ngi dn
hon ton c th yn tm v cht lng cng trnh kh sinh hc. - Ngoi ra, mi cng
trnh kh sinh hc u c t th xy bo hnh min ph trong mt nm u hot ng. -
Sau khi xy dng xong cng trnh, cc h dn s c tham gia tp hun v cng ngh
kh sinh hc, v cch thc vn hnh v bo dng cng trnh kh sinh hc. V nhng
ng gp to ln ca D n trong cc lnh vc nu trn, thng 4/2007, D n c trao
gii thng Nng lng ton cu nm 2006 ti Brussel, B. y l gii thng danh gi
trao cho cc D n c ghi nhn l c ng gp to ln trong vic gim thiu hin
tng nng ln ca Tri t.