KHOA HOC - C 6 N G NGHE
KHAO SAT THirC NGHIEM CHAT LI/CTNG KHI TONG HOP CUA LO KHl HOA LOI NGO XUOI CHIEU LIEN TUC QUY MO CONG NGHIEP
Nguyen Dinh Titng' TOM TAT
Bdi bdo ndy trinh bdy kit qud nghien ciru thirc nghiim ddnh gid chdt lugmg khi tdng hgp cd thi ddt chdy dirge ciia Id khi hda Wi ngd xudi chiiu quy md cdng nghiep. Kit qud cho thdy trong khi long hgp syngas cdc Ihdnh phdn khi dgt dugc nhu sau: CO ^ 15.01%, Hi =^=2.65%. CH., ^10,9%. Nhd kel qud ldi uu hda thuc nghi$m da tim dirge cdc thdng sd tdi inr di chdt lirgrng khi tdng hgp dgt dugc tdt nhdt. cy thi cdc thdng sd tdi im: do dm (15.12%);^ hru lirffng gid (5},52m^/h); ty 14 nhiin li^u lieu ihg (148,81 Kg/h).
Tir khod: Khi long hgp. Id khi hda Wi ngd, khi hda xudi chiiu lien luc Wi ngo.
EXPERIMENTAL INVESTIGATION OF SYNGAS QUALITY AN INDUSTRIAL IN CONTINUOUS-FLOW DOWNDRAFT CORN COB GASIFIER
Nguyen Dinh Tung' SUMMARY
The paper presents the results of an experimental study designed to evaluate the syngas quality which can be burnt in an industrial continuous-flow downdraft com cob gasifier. The results show that the syngas consists of CO =15.01%, H2 == 2.65%, CHj = 10.9%. By results of an experimental optimization, the optimal parameters required to achieve the best syngas quali^ are found. The specific optimal parameters are; the moisture content (15.12%); the air flow ratio (51.52 m/h); the fuel consumption ratio (148.81 kg/h).
Keywords: Syngas, com cob gasifier, continuous downdraft gasification of com cob.
I. DAT VAN DE
Theo so lieu ciia Tong cue Thong ke, hien cd nuoc CO khodng 800.000 ha ngo. Qud trinh chl biln nong sdn da thai ra moi truang khoang 800 nghin tan I6i ngo moi nam [1,2]. Lugng loi ngo nay moi dugc ngugi ddn sii dung mpt phdn lam chdt dot, mpt phdn rdt nho dugc diing de trong ndm, con Iai chii yeu thai bo ra ngoai v?
duong, dong suoi gay 6 nhiem moi truong.
Chinh vi the can tim ra gidi phap cong nghe de tai su dung lugng phu phdm du thira chuyen doi thdnh nang lugng nhiet so cap theo cong nghp khi hoa dua vao sir dung trong c h l biln nong san (sdy ngo), viec irng dung phuang phap khi hoa Ioi ngo gidi quylt dugc tinh cdp thilt vd la Iai giai t l i uu cho vdn d l neu tren. D I tao ra ndng lugng sach cho sdy nong sdn, mang Iai ' PGS. TS. Vien nghien ciJu ihiit kk chi tao may nong nghiep.
hieu qua kinh te, ndng cao chat lugng sdn pham xudt khdu, va gop phdn gidm thieu 6 nhilm moi truong. Hieu qua kinh te dem lai din ddu con phu thuoc vao chdt lugng khi tong hgp syngas sinh ra tir san pham ciia 16 khi hoa. Vi?c khdo sdt thuc nghiem chat Iugng khi ting hgp syngas de dua vao ling dung trong sdn xuat nhdm ndng cao hieu qua kinh te va moi truang la cdn thiet.
II. VAT Ll£U, PHU'ONG PHAP VA THIET BI NGHIEN Ciiru
- Vgt li^u nghien citu: Vat lieu nghien ciiu la I5i ngo 6 viing Scm La thai ra v? duang sau khi te ldy hat d l sdy. Cac ddc tinh ly, hoa, ddc biet Id cdc thdnh phan hoa hpc ciia nguyen lieu nhu: ham Iugng ciia cdc bon (C), oxy (O), ...vd nhiet tri thdp ciia nhien lieu Hu dugc thl hien
TAP CHf CONG NGHIEP NONG THON - SO 20 - 2015
KHOA HQC - CONG NGHf trong bang 1 co anh huong rat 16n den ty Ie sinh
khi va chat lugng khi tong hgp sinh ra.
Bdng 1. Cdc dgc tinh ly ~ hoa cua loi ngd [1-2]
phln (%) LOl np6
(C) 43,6 Khoi Itj^g neng
(H) 5.2
(0) 41.6
(N) 0,15
(S) (a) 3,05
(w) 6,4
(k|/kB) 15,65 245 (kg/m')
- Phuffng phdp nghien ciiu: Phuong phap nghien ciiru trong bai bao ndy dugc ket hgp giira phucmg phap nghien cuu thuc nghiem va phuong phap quy hoach thuc nghiem toi uu.
- Thiet bi do trong nghien cuu: Dp chinh xac ciia ket qud thuc nghiem chiu anh huang bai nhieu yeu to, trong do mpt phdn Id do thiet bi do. Cac thiet bi do (hinh 1) dugc sir dung trong thuc nghiem, gom:
a- Can bdn de xac djnh khoi lugng (VN);
b- Thiet bi do nhiet do cam tay kieu siing bin (Ebro - CHLB Due);
c- May do ltm lugng va v^n toe gio (Testo - CHLB Dtic);
d- Cac bien tan dieu khien toe do dgng ca;
e- Ampe ldm dodiennangtieuthu (CHLB Due);
f- May do do dm vat lieu truoc khi khi hoa;
g- Thiet bi do quan trac moi truang; ngoai ra CO cac sensor/cdm bien nhiet do de theo doi nhiet do ben trong thdn 16 phdn img.
Hinh 1. Thiet bi do vdphdn tich khi quan trdc mdi truorng khi thuc nghiem - Thiet bi nghien cii-u: Hinh 2 Id thilt bi nghien cuu (16 khi hoa Ioi ngo xuoi chilu lien tuc quy mo cong nghiep). Nguyen lieu Ioi ngo dugc n^p vao 16 tir ben tren dinh 16 nho thilt bi gau tai. Khong khi (trong do co oxy) dugc cap
vao 16 nho qu^t gio cung theo chilu tir tren xulng, qua trinh khi hoa dien ra tai luc khi ting hgp syngas sinh ra va dugc ldy mau dl phan tich ty le cdc thanh phdn khi va do true tilp bdng thiet bi do quan trdc dien tu hien sl, Khi ting hgp syngas lien tuc dugc sinh ra va dugc dan dua ra ngoai 16 nh6 he thing Ing dan khi gas dl dua din buIng dlt. Tai buIng dlt khi ting hgp syngas dugc dlt chdy khi co Iugng oxy thiir cdp CO trong khong khi khi dugc cdp cuotig buc vao de dot chay thanh ngpn lira (hinh 2 ben phai).
Doi vai tro se dugc thai ra duoi day 16. Qua trinh nap Ii?u, xd Iro, vd sinh khi syngas dugc dien ra lien tuc tir khi bdt ddu hoat dgng cho din khi CO nhu cau dimg 16.
72 TAP
Tfinh 2. Thiet bi nghien ciru (Id khi hoa ldi ngd) de khdo sdt khd ndng, ty le sinh khi syngas HI. KET QUA VA THAO LUAN
3.1. Ket qud nghien ciru thuc nghifm Qud trinh khao nghiem 16 khi hoa Ioi ng6 nham danh gia chdt lugng khi tong hgp Syngas sinh ra. San pham khi syngas dugc ldy mau dua di phan tich tai ph6ng thi nghiem ciia "Cong ty CO phdn cong nghe than thien moi trucmg Bach khoa", voi muc tieu phdn tich xac djnh nong dp ciia cac thanh phdn khi (CO, H2, CH4...) co trong khi tong hgp Syngas. Ket qua dugc the hien nhu tren bang 2.
Chdt lugng khi ting hgp syngas sinh ra dugc ddnh gia tren ti 1? cdc thanh phdn khi (CO, CH4, H2) CO trong khi Syngas. Kit qua cho thay gia tri trung binh ve t^ le cua cac khi thanh phdn CO trong khi ting hop Syngas nhu sau: khi CO CHI CONG NGHliP NONG THON - SO 20 - 2015
KHOA HQC - CONG NGHE
(15,01%), khi H2 (2,65%), khi CH4 (10,9%). thuc nghiem nham toi uu hoa qua trinh khi hoa Ngoai ra de xdc djnh cac thanh phdn khi nay dat voi muc tieu lua chpn cac gid tri dau vao co dp dugc gia tri toi uu, tac gia dua vdo quy hoach tin cay cao.
Bdng 2. Kit qud thuc nghiem kiem tra thdnh phdn khi khoi Lan do
1 2 3 4 5 6 7 8 9 TB
V | tri lay mau
Tren ducmg ong dan khi ra cua he th6ng 16
Ket qua CO 17,02 17,32 16,44 11,93 8,22 16,24 16,44 16,39 15,12 15,01
do thanh H2 3,23 3,17 3,15 2,20 0,86 3,13 3,16 3,15 1,80 2,65
phan khi CH, 12,31 12,22 12,19 8,90 6,72 12,31 12,22 12,18 9,08 10,90
DoTi vi
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3.2. Ket qud nghien cuu toi uu theo phuangphdp quy hogch hda thgx nghiem
Cac ySu to cong nghe chinh anh huong den chat lugng cac thanh phan khi nhu CO, H2, CH4 CO trong khi tong hgp Syngas dugc sinh ra Id sdn phdm ciia 16 khi hoa trong qua trinh thuc nghiem, do la do dm cua vdt lieu thi nghiera, luu lugng gio cdp, ty 1^ nhien Heu tieu thu. Do co nhilu biln sl thay doi vai nhilu muc khac nhau, muln gidm sl lugng thi nghiem ma van dam bao chinh xac ket qud, can phdi su dung phuang phdp quy hoach thuc nghiem, tir do xac dinh dugc cac thong sl tli uu lam co so thiet lap quy trinh van hanh de tao ra san pham phii hgp voi nghien cuu thyc tien. Trong nghien cuu nay, tac gid lira chpn ma tran Box-Behnken voi 3 yeu to anh huong da dugc ma h6a sir dung cho nghien cim dli vai 16 khi hoa lien tuc.
Yeu t l anh huang dd dugc md hoa:
Xl - Dp dm vdt Iieu/I5i ng6(%) X2 - Luu lugng gio (m^/h) X3 - Ty Ie nhien lieu tieu thu (Kg/h)
Tien hanh thuc nghiem theo phuang an xdy dung cac ham todn dua tren cac phuang trinh hoi quy duoi dang cac da thiic bac 2. Ket qud thuc nghiem mot so yeu to anh huong tai qud trinh khi hoa, theo ma tran Box-Behnken dugc the hien trong bang 3.
Bang 3. Gid tri md hda cUa cdc yeu Id khi thuc nghiem khi hoa loi ngo Bien so
Do am vat lieu/loi ngo Luu lirong gio Ty le nhien lieu tieu thu
Ky hieu X, X, XJ
Don vi m'lh
%
Kg*
Mjc -1 10 50 100
0 13 55 125
1 16 60 150 Tren bang 3 cho thay do am vat lieu bien thien trong khoang 10 - 16% am, lim luong gio bi§n thien trong khoang 50 - 60m^/h va lugng nhien lieu tieu thu trong qua trinh khi hoa bien thien trong khoang 100 - 150Kg/h.
Mat khac chat lugng qua trinh khi hoa dugc danh gia qua 3 yeu to:
Yl - Ty le lugng khi CO (%) Y2 - Ty le lugng khi H2 (%) Y3 - Ty le lugng khi CH, (%) Tita hanh xay dung ham h6i quy bac 2 cho cac muc tieu:
Y, = a„ + ai*Xi + a3*X2 + aj'Xj + ai,»X,' + aji'X,' + ajj*Xj' + ai2*X, X; + au*X, Xj + a2j»X; Xj TAP CHI CONG NGHIEP NONG THON - SO 20 - 2015
(1) 73
KHOA HQC - C 6 N G N G H ( ;
Y , = b . + bi*X, + b2*X2 + b,*X3 + b | i * X i ' + b,2*X2^ + b j j ' X j ^ + b i i ' X , X j + b , j » X , X j + b j j ' X ; X j (2) Y J = C„ + C|*X, + C,*X2 + C j ' X ) + C,|»X,^ + C22*X2^ + Cj,»X,' + C|2*X| X ; + C|3*X| X j + C i j ' X ; X j ( 3 )
Bang 4. Ma trgn Ihuc nghiem ldi uu hoa qua Irinh khi hoa Id lien tuc Iheo quy hogch Box-Behnken doi vai loi ngo
N ' E x p 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
XI -1.0000
1.0000 -1.0000 1.0000 -1.0000 1.0000 -1.0000 1.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
X2 -1.0000 -1.0000 1.0000 1.0000 0.0000 0.0000 0.0000 0.0000 -1.0000 1.0000 -1.0000 1.0000 0.0000 0.0000 0.0000
X3 0.0000 0.0000 0.0000 0.0000 -1.0000 -1.0000 1.0000 1.0000 -1.0000 -1.0000 1.0000 1.0000 0.0000 0.0000 0.0000
Yl 13.61 16.12 12.97 17.32 12.37 17.38 14.64 17.25 14.38 15.05 16.64 17.01 15.53 15.64 15.53
Y2 1.67 3.23 2.60
^ 2 . 8 7 2.10 3.25 2.06 3.15 2.50 2.63 2.75 2.90 3.10 2.89 3.13
Y3 8.54 11.85 9.10 12.35 8.50 11.60 7.60 12.10 9.72 11.68 11.05 11.75 10.69 9.56 10.25
Xdy dung bang gid tri he so hoi quy ciia cac ham muc tieu nhu bang 5.
Bang 5. Gid tri he so hoi quy hdm muc tieu He so hoi quy ham Yi
He so ao ai a2 33 ail a22 a33 ai2 ai3 a23
Gia tri 15,567 1,810 0,200 0,795 -0,461 -0,101 0,304 0,460 -0,600 -0,075
He so hoi quy ham Y2 He so
bo bl b2 b3 bii b22 b33 bi2 bi3 b23
Gia tri 3,040 0,509 0,106 0,048 -0,251 -0,196 -0,149 -0,323 -0,015 0,005
He so hoi quy ham Y3 He so
Co Cl cz C3 Cll C22 C33 C12 C|3 C23
Gia tri 10,167 1,770 0,465 0,125 -0,403 0,697 0,187 -0,015 0,350 -0,315
Tu do ta xac dinh dugc cac phugng phuong trinh hoi quy (1), (2), (3) nhu sau:
Phuong trinh hoi quy ty le lugng khi CO sinh ra:
Y| = 15,567 -^ l,81*Xi + 0,2*X2 + 0,795*X3 - 0,461*Xi^ - 0,101'X2^ + 0,304*X3^ + 0,46'X, X2 - 0,6*Xi X3 - 0,075*X2 Xj
Phugng trinh hoi quy ty le lugng khi H2 sinh ra:
Y2 = 3,04 -I- 0,509*Xi + 0,106*X2 + 0,048»X3 - 0,25I*Xi^ - 0,196*X2^ - 0,149*X3^ - 0,323*Xi X2 - 0,015»Xi X3 + 0,005*X2 X3
74 TAP CH( CONG NGHIEP NONG TH6N - SO 20 - 2015
K H O A H Q C - CONG N G H E Phuang trinh h l i quy ty le lugng khi CH4 sinh ra:
Y3 = 10,167 + 1,77*X| + 0,465*X2 + 0,125*X3 - 0,403*Xi^ + 0,697*X2^ + 0,187*X3^
0,015*X, X2 + 0,35*Xi X3 - 0,315*X2 X3
Tren co so nay thilt lap cac mo hinh bieu dien cac gia tri tir cdc phuang trinh h l i quy tren.
Thiet lgp mo hinh ty le lur^xg khi CO:
Mo hinh ty Je lugng khi CO sinh ra cua qud trinh dugc bieu diln theo phuong trinh (1). Gia tri cac he so hoi quy dugc the hien trong bang 5.
Tir day ta co mo hinh danh gia ty le lugng khi CO nhu hinh 2.
Thiet lap mo hinh ty le tuffng khi CH4:
Mo hinh ty le lugng khi CH4 sinh ra cua qud trinh dugc bieu dien theo phuang trinh (3) cimg voi gia tri cac he so hoi quy dugc the hien trong bdng 5 ta co mo hinh danh gia ty le lugng khi CH4 nhu hinh 4.
^
Hinh 2. Md hlnh ddnh gid ly le luang khi CO
He s6 xac dinh R"= 0,982, he so diSu chinh R^A= 0,949 cho thjy mo hinh hoan toan tucmg thich vgi thuc nghiem.
Thiit lap mo hinh ty le lucmg khiHi:
Mo hinh ty le lugng khi H2 sinh ra cua qua trinh dugc bi6u diln theo phuong trinh (2). Gia tri cac he s6 h6i quy dugc thS hien trong bang 5. Tu day ta co mo hinh danh gia ty le lugng khi H2 nhu hinh 3.
' ' . • • • m-i
>
Hinh 3. Mo hinh ddnh gid ty le luang khi H2
He s l xac dinh R = 0,961, he so dieu chinh V}^= 0,892 cho thdy mo hinh hodn toan tuong thich voi thuc nghiem.
Hlnh 4. Mo hinh ddnh gid ty le lugrng khi CH4
He so xdc dinh R^= 0,953, he so dieu chinh R^A= 0,868 cho thdy mo hinh hodn toan tuong thich voi thuc nghiem.
• Toi UTI hoa
Tien hanh toi uu h6a cdc yeu to anh huang toi ty le lugng khi sinh ra ciia qua trinh khi hoa theo thuat toan ham mong dgi voi 3 hdm muc tieu nhu sau:
Ty le lugng khi CO mong dgi can dat dugc lan nhdt,
- Ty le lugng khi H2 mong dgi can dat dugc Ion nhat,
Ty le lugng khi CH4 mong dgi cdn dat dugc lan nhdt,
Kit qua tli uu hoa dugc the hien qua bang 6.
Bdng 6. Chi do cdng nghe toi uu cua qud trinh khi hoa loi ngo
Bien so Dp am vat lieu/loi ngo, % Luu lugng gio, ra"'/h Ty le nhien lieu tieu thu, kg/h
Gia tri 15,12 51,52 148,81
TAP CHf CONG NGHIEP NONG THON - SO 20 - 2015
K H O A H Q C - CONG N G H E Bdng 7. Thdng ke kel qud tdi uu cua qud Irinh khi hoa loi r Ket qua
Ty le luong khi CO Ty le lugng khi H2 Ty le lugng khi CH4 Ham mong dgi chung (D)
Gia tri tinh toan
16,88 3,16 11,97
Do lech chuan
1,599 0,472 1,512
Gia tri nhd nhat
12,370 1,670 7,600
Gia tri 16nnh4t
17,380 3,250 12,350
Gia tri trung binh
14,875 2,460 9,975
di%
99,98 96,75 99,96 98,90
Tir bang 6 cho thdy dp dm vat li§u dugc lua chgn la 15,12% a do am nay thi ty le nhien lieu tieu thu la 148,81 Kg/h va luu lugng gio cdn cung cdp cho qua trinh khi hoa la 51,52 m /h.
Voi cac ty le nay qua trinh khi hoa da dat dugc hieu qua mong dgi, dieu kien toi uu nay ciing tuong doi phil hgp vol ket qud thuc nghiem. Ket qua 6 bang 7 ciing cho thdy kha nang dat dugc ham tli uu ciia ty le lugng khi CO la 99,98%, ciia ty le lugng khi CH4 la 99,96%, ham muc tieu cua ty le Iugng khi H2 la 96,75%. Xet chung cac muc tieu thi ham mong dgi dgt dugc 98,90%.
IV. KET LUAN
Tir kit qua khao sat do dac thuc nghiem va ket qua quy hoach thuc nghiem toi uu doi vai ty le cac thanh phdn khi CO, H2, CH4 co trong khi t i n g hop Syngas tuong ung nhu sau: khi CO (15,01% va 14,9%), khi H2 (2,65% va 2,5%), khi CH4 (10,9% va 10%), qua do cho thdy dp chenh lech ket qua khong nhieu. Dieu nay chimg to mo hinh thong ke thuc nghiem dat dugc ket qua toi uu vai cac thong so nhu: dp dm (15,12%); luu lugng gio (51,52m^/h); ty le nhien lieu tieu thu (148,81 Kg/h) da dat du dp tin cay dam bao ty le lugng khi tong hgp sinh ra trong qua trinh khi hoa lon nhdt va luon on dinh.
Tai lieu tham khao
[1]. Nguyen, Dinh Tung (2009). Theoretische und experimentele Untersuchungen zur energietische Nutzung von landwirtschaftlichen Abfallen aus Vietnam. Dissertation Universitat Rostock, Deutschland.
[2]. Nguyin Dinh Tung v^ cs. (2014): Nghien cihi thiet ke, che t?o 16 khi hoa lien tuc phu phkm nong nghi?p (vo trau, I5i ngo) quy mo cong nghiep, De tai nghien cuu cap Nha Nuoc 2014, Bo Cong ThucFng.
[3]. Martin Kaltschmitt, Hans Hartmann, Hermann Hofbauer. 2011. Energie aus Biomasse, 3 Aufl^e, Springer Berlin Vedag Springer Verlag.
[4]. UNDP. 2005. Biomas Energy for Heating and Hot Water Supply in Belarus. Best Practice Guidelines, Part A: Biomass Combustion.
[5]. Tung D. Nguyen. 2009. Present State, Potential and the Future of electrical Power Generation from Biomass Residues in Vietnam. Agricultural Engineering International: the CIGR Ejoumal.
Ngay nhan bai: 15/11/2015 Ngay phan bi^n: 05/12/2015 Ngiroi phan bi?n: PGS.TS. Biii Hai Trieu, Hoc vi?n NSng nghiep Viet Nam.
76 TAP CHl CONG NGHIEP NONG THON - SO 20 - 2015