36 Cong nghf chuyen h6a khi thien nhien thanh nhien lifu long: kha nSng ^p dung d ViftjNam,<br />
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CONG NGHE CHUYEN HOA KHI THIEN NHIEN THANH NHIEN<br />
LIEU LONG: KHA NANG AP DUNG 6 VIET NAM<br />
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Pham Van Khang<br />
Trung tdm Nghien ciru vd Phdt trien Che bien Ddu khi<br />
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TOM T A T<br />
Vai trd ciia khi thien nhien trong nin kinh ti ciia cdc mrac khdc nhau khong giong<br />
nhau. nhung nhin chung ngdy cdng co vai tro to lan trong moi linh vuc cua nen kinh te.<br />
Khi thien nhien duac sir dung rong rdi trong cdc linh vice sdn xudt ndng luang. cong<br />
nghiep, trong cong nghiep hod hoc vd trong ddn dung, tuy thuoc vao cdc muc dich ciia<br />
cdc ho sic dung. Cung cdp khi den cdc ho sic dung doi hoi phdi co he thong ong ddn. Tuy<br />
nhien. khong phdi bdt cie ddu cdn Id ngicai ta co the cung cdp khi den do duac do cdn tra<br />
cda viec xdy dimg he thdng dng ddn khi phdi duac tinh todn phii hap vd hieu qud.<br />
Di CO the cung cdp khi din cdc ho sic dung thudn tien, ngodi viec ddn khi true tiep<br />
bdng duang dng, nguai ta nghien cicu phdt trien nhieu phuang phdp chuyen khi thdnh<br />
dgng long di van chuyin di ddng. Co the chuyen khi thdnh dang long bdng each bien doi<br />
vat ly: nen vd ldm lanh - qud trinh nen khi duai dp sudt cao vd ldm lanh de hod long khi.<br />
hodc biin ddi hod hoc: chuyen hod hod hgc trong do cdc phdn tic khi bi bien doi hod hgc<br />
vd kit hap tao thdnh dgng long ben vimg sir dung true tiep ldm nhien lieu van tdi hoae<br />
ldm nguon nguyen lieu cho cdng nghiep hod hgc.<br />
Khi khai thde a Viet Nam hien nay chu yeu de sdn xudt dien, sdn xudt dgm. Trong<br />
tuang lai neu cdc de dn sir dung khi duac dua vdo hogt dgng thi sdn phdm tic khi se da<br />
dgng han.<br />
N gi dung bdo cdo nay trinh bay su nghien cuu khd ndng chuyen hod khi thdnh long<br />
(chuyen hod hod hgc) bdng cdch tgo ra khi tong hap vd sic dung qud trinh Fischer<br />
Tropsch chuyen hod khi thien nhien thdnh dgng Idng. Muc dich Id nhdm gop phdn ndng<br />
cao khd ndng sic dung khi thien nhien ciia Viet Nam vd co the dp dung doi vai cdc mo khi<br />
CO dieu kien khong thuan lai trong viec cung cdp khi tai cdc hg tieu thu.<br />
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QUA TRINH CHUYEN HOA KHI THIEN NHIEN T H A N H LONG<br />
Cdng nghe mdi dugc phat triln va ap dung dl chuyen hoa khi thien nhien thanh long<br />
la cdng nghe chuyin hoa khi thanh Idng (Gas To Liquids - GTL). Chuyen hoa khi thanh<br />
long cd thi ap dung va thilt kl tdi uu ddi vdi cac md khi nhd. Anh hudng manh nhat din<br />
kha nang canh tranh ciia viec ap dung cdng nghe chinh la chi phi dau tu, chi phi hoat ddng<br />
cua nha may, chi phi nguyen lieu, quy md va kha nang dat dugc hieu qua sir dung cao<br />
trong san xuit. Tuy nhien, theo danh gia chung, chuyin hoa khi thanh long khdng thi<br />
Tuyen tap bao cao Hpi nghj KHCN "30 nam Dau khi Vift Nam: Co" hpi mdi, thach thiic mdi" 37^<br />
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canh tranh vdi san xuit diu, trir khi bugc phai tan dung khi cd gia trj thip va van chuyin<br />
khd khan.<br />
Mat uu viet eua chuyin hoa khi thanh long khdng chi eho san pham cd gia trj ma cac<br />
san phim edn cd thi ban hoae pha trdn vdi san pham lge dau thanh cac san pham cao cap<br />
it gay d nhiem mdi trudng. Cdng nghe chuyen hoa khi thanh Idng san xuat ra nhien lieu<br />
diezen cd du kha nang nhu diezen truyen thdng, nhung lai cd chi sd cetan cao hon cho<br />
phep chiing ta thilt kl ddng eo manh hon. Hon nira, ham lugng luu huynh va ham lugng<br />
hydrocarbua tham trong diezen tir edng nghe GTL rat thap nen giam dang ke sy d nhiem<br />
va ddc hai mdi trudng. Sir dyng diezen ed ham lugng Iim huynh va hydrocarbua tham<br />
thap la yeu cau mang tinh chat toan cau hien nay.<br />
Cd hai cdng nghe GTL phd bien: chuyen hoa true tiep khi thanh san pham dau md<br />
tdng hgp (syncrude), va chuyen hoa gian tiep qua qua trinh khi tdng hgp (syngas). Cd mdt<br />
sd qua trinh chuyen hoa trye tiep dugc nghien ciiu, nhung khdng qua trinh nao dugc<br />
thuong mai hoa do khdng hap dan ve phuang dien kinh te. Chuyen hoa gian tiep cd the<br />
tien hanh bang qua trinh Fischer-Tropsch (F-T) hoae san xuat metanol.<br />
Trong so dd trinh bay su sir dyng khi, trong dd ed qua trinh chuyen hda khi thien<br />
nhien. Qua trinh chuyen hoa khi thien nhien thanh nhien lieu long sir dyng qua trinh<br />
Fischer-Tropsch duge chia lam cae bude:<br />
- San xuat khi tdng hgp<br />
- Chuyen hoa Fischer-Tropsch<br />
- Hoan thien san pham<br />
San xuat khi tdng hgp sir dyng cae phuang phap chuyen hoa khae nhau nhu<br />
refoming hoi nude, reforming dioxitcarbon, refoming ty cap nhiet, oxy hoa mdt phan hoae<br />
plasma.<br />
Qua trinh Fischer-Tropsch cho nhieu san pham khae nhau tir khi metan den butan,<br />
naphta, xang, dau hoa, diezen, dau nang, sap, cae chat oxy hoa, nhung chu yeu van la cac<br />
san pham trung binh (xang, dau hoa, diezen, dau nang). Hieu suat san pham tuy thudc rat<br />
nhieu vao cac cdng nghe ap dyng, dieu kien van hanh nhu ap suat, nhiet do, ty le H2/CO;<br />
thanh phan xiie tac; kieu thiet bj xiic tac: tang cd djnh, tang sdi hay tang huyen phii.<br />
Mdt nha may chuyen hoa khi thien nhien thanh long bao gdm 4 phan xudng co ban<br />
sau:<br />
Phan xudng san xuat khi tdng hgp: chuyin hoa khi thien nhien thanh hdn hgp khi<br />
CO va H2.<br />
Phan xudng tdng hgp Fischer-Tropsch: trong phan xudng nay CO va H2 trong<br />
khi tdng hgp dugc chuyen hoa thanh cac hydrocarbon thdng qua cae phan ung<br />
phiic hgp.<br />
38 C o n g n g h f chuyen hda k h i thien nhien t h a n h nhien l i f u idng: kha n a n g a p d u n g 6 V i f t j | ; ^ j j ] l<br />
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• Phan xudng tach va hoan thien san pham.<br />
• Phan xudng xir ly nude.<br />
Ngoai ra, tuy thudc vao cdng nghe ma cd hoae khdng cd phan xudng san xuat oxy.<br />
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Bien doi<br />
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C vat ly<br />
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I \ Dung moi<br />
San xuat<br />
Chii Ihich: Dimetyl ete<br />
SRM: refoming hoi nude (steam<br />
reforming)<br />
ATR: refoming t^^ cap nhi^t TdNG I MTBE Olefin<br />
POX: oxy hoa mpt phan<br />
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Acetyl<br />
Dung trong ^ San xuat<br />
NMLD Hydro<br />
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Chuyen<br />
Ure