ISSN 2086-5953
2 MODEL, ANALYSIS, DESIGN,
AND IMPLEMENTATION
2.1 Laboratory Melting System
The melting system consists of a high- temperature furnace, a secondary combustion
chamber, and one set of APCDs including a cooling unit collects the condensed water of the volatile
gas, a filter collects particles, and three-stage glass PUF cartridge adsorption collects the
gaseous phase compound as illustrated in Figure 1. The specifications of the melting system are as
follows. The high-temperature furnace has a width of 210 mm, a length of 280 mm, and a height of
220 mm, with a maximum temperature of 1600 °C, and the heat loading is 6.6 kW. The furnace has an
inner graphite crucible, and on top of this crucible is a cone-shaped cap hood for collecting volatile
gases. The volatile gases collected by the cap hood will be delivered with an Al
2
O
3
tube to the secondary
combustion chamber
for further
combustion or introduced to the APCDs. The secondary combustion chamber has an inside
diameter of 50 mm and a length of 1000 mm, with a maximum temperature of 1300 °C, and the heat
loading is 6.6 kW. The flue gas cooling unit with indirect water cooling has an inside diameter of 25
mm and a length of 1700 mm. The diameter of the filter is 51 mm, and each stage of the three-stage
PUF cartridge adsorption has a length of 130 mm. Three separate tests were performed by measuring
PBDE in the third stage of the PUF cartridge to ensure the gaseous PBDE are insignificant, , and
less than 2 PBDE mass was found at the third stage of the PUF cartridge. The waste flexible
PBDE were first cut into small pieces ca. 5 x 5 x 0.5 mm, and metals on the surface were stripped
off by aqua regia extraction. The waste PBDE was pretreated to prevent the metals from corroding the
equipment. The concentrations of Al, Cu, Ni, and Au in the extraction solution were analyzed with
the same ICP-AES instrument. When the metals were stripped off the surface of the waste PBDE by
the aqua regia solution, the concentration of metals was reduced by 75-95 and the weight of the
PBDE reduced by approximately 25. The experimental sample placed inside a graphite
crucible was put in the furnace; the furnace temperature was than increased to 850 or 1450 °C
at 6 °C min
-1
held for 30 min, with the secondary combustion chamber at 900 °C. The pump rate for
withdrawing gaseous samples was 10 L min
-1
. The batch experiment was repeated twice. After the
pyrolysis process, the bottom ash, fly ash, and cartridge were collected and analyzed to determine
the concentrations of PBDE on the basis of the National Environment Analysis Method NIEA
M801.11B of Taiwan, similar to USEPAB modified method 23A [3].
Figure 1. High-temperature melting system: 1 bottom ash, 2 cooling unit, 3 filter, 4 glass PUF cartridge
2.2 PBDE Analysis
Analyses of PBDE samples were performed in a certified laboratory in Taiwan to analyze
PBDE. Each sample was spiked with a known standard and extracted for 24 h. Then the extract
was concentrated and treated with sulfuric acid; this was followed by a series of cleanup and fraction
procedures. The standard solution was added to the sample before PBDE analysis to ensure the
recovery during analysis. Because of a lack of other standards, seven individual PBDE including four
individual PBDE sand three individual PBDE were analyzed
by using
high-resolution gas
chromatographymass spectrometry HRGCMS. The HRGC instrument Hewlett-Packard 6970
series gas, California was equipped with an RTX- 5MS column L 30 m, i.d. 0.25 mm, film
thickness 0.25 ím and splitless injection JW Scientific, California. The oven temperature was
programmed according to the following: initial temperature at 150 °C held for 1 min, increased to
220 °C at 40 °C min-1, then increased to 240 °C at 2 °C min-1, and then increased to 310 °C at 10 °C
min-1 held for 1 min. Helium was used as the carrier gas. The HRMS instrument Micromass
Autospec Ultima, Manchester, U.K. was equipped with a positive electron impact EI+ source. The
analyzer mode was selected ion monitoring with a resolving power of 10000. The electron energy and
the source temperature were set at 35 eV and 250 °C, respectively. The method detection limits of the
seven individual PBDE for bottom ash samples, cooling unit samples, filter samples, and glass PUF
cartridge samples were found between 0.318 and 4.132 ngkg, 0.001 and 0.008 ng, 0.001 and 0.021
ISSN 2086-5953 ngNm
3
, and 0.004-0.071 ngNm
3
, respectively. The recovery
for the
seven individual
PBDE compounds ranged from 50 to 107 [3].
3 RESULT
The PBDEs content before washing from 50
o
C to 1450
o
C as list on Table 1. Highest value occur at temperature 1200
o
C and it is about 33137 pgg. From Figure 1, PBDEs content remain the
same from 50
o
C to 1000
o
C, but it drastically change after 1000
o
C.
Table 1. Temperature vs PBDEs content, before washing
Temperature Celcius
PBDEs content pgg, before washing
50 706
100 896
150 900
200 1100
250 532
300 583
400 1120
500 534
600 585
650 556
750 742
850 515
900 514
1000 1172
1100 23100
1200 33137
1300 30974
1350 24514
1450 1797
The PBDEs content after washing from 50
o
C to 1450
o
C as list on Table 2. Highest value occur at temperature 1300
o
C and it is about 492 pgg. PBDEs content from 1100
o
C to 1350
o
C have unstable concentration and it is due to the de Novo
synthesis Figure 2.
Table 2. Temperature vs PBDEs content, after washing
Temperature Celcius
PBDEs content pgg, after washing
50 392
100 287
150 245
200 248
250 178
300 378
400 330
500 187
600 182
650 390
750 423
850 403
900 373
1000 258
1100 328
1200 321
1300 492
1350 375
1450 394
Figure 2. Temperature vs PBDEs content, before washing
ISSN 2086-5953 The PBDEs content before washing have
similar pattern, but after washing, the reformation are not shown, was shown on Figure 3. It means
that before washing, bromine on PBDEs content does not wash.
Figure 3. Temperature vs PBDEs content, before and after washing
4 CONCLUSION AND DISCUSSION
Total PBDEs concentration before washing is 23100, 33137, 30974, 24514 pgg, respectively,
occur at temperature from 1100
o
C to 1350
o
C. It has unstable concentration, causing by de Novo
synthesis. Total PBDEs concentration after washing has concentration from 392 to 394, with various
concentration. Its because chlorine had already wash out. Fly ash before washing has reduction
reformation through de Novo synthesis, compare with fly ash after washing. In order to develop
dioxin inventory, the activity data for the entire country as well as a local area need to be
established and updated by the environment protection department. In addition to air, PBDEs
are released to other media or compartments, e.g., water, land, product, and residue, which were
neglected in Taiwan. These issues need to be considered in the future.
REFERENCES
[1] Chen, C.K., Lin, C., Lin, C.W., Guo-Ping, C.C 2006a The size distribution of
polychlorinated dibenzo-p-dioxins
and dibenzofurans in the bottom ash of municipal
solid waste incinerators, Chemosphere, Vol. 65, pp. 514
–520. [2] Darnerud, P-A., Eriksen, G-S., Johannesson,
T., Larsen, P-B., Viluksela, M 2001 Polybrominated Diphenyl Ethers: Occurrence,
Dietary Exposure, and Toxicology, Environ Health Perspect, Vol. 109, pp. 49-68.
[3] Lai, Y.C., Lee, W.J., Li, H.W., Lin, C.W., Guo-Ping,
C.C. 2007
Inhibition of
Polybrominated Dibenzo-p-dioxin
and Dibenzofuran Formation from the Pyrolysis
of Printed Circuit Boards, Environ. Sci. Technol, Vol. 41, pp. 957
–962. [4] Weber, R., Kuch, B. 2003 Relevance of
BFRs and thermal conditions on the formation pathways of brominated and brominated
– chlorinated
dibenzodioxins and
dibenzofurans, Environ. Int, Vol. 29, pp. 699 –
710. [5] World
Health Organization.
1998 Polybrominated
Dibenzo-p-dioxins and
Dibenzofurans. In: Environmental Health Criteria 205. World Health Organization,
Geneva, Switzerland.
87 ISSN 2086-5953
SMOOTHED PARTICLE HYDRODYNAMIC MODEL FOR DAM BREAK PROBLEM WITH OBSTACLE AND
OBSTACLE-CLEARANCE
Syamsuri
1
, Tungga Bhimadi
2
, Junaidillah Fadlil
3 1
Department of Mechanical Engineering National Taiwan University of Science and Technology
2
Department of Naval Engineering Sepuluh Nopember Institute of Technology
3
Department of Computer Science and Information Engineering National Taiwan University of Science and Technology
Email: syam_sby2003yahoo.com
1
ABSTRACT
Dam break flow has been the subject of intensive research for a long time. Dam break flow
includes several features of existing problems in the area of fluid mechanics, environment protection,
marine hydrodynamics, and coastal engineering. Dam break flow is widely used as a classical test
case for numerical simulation of free surface and moving boundary. Solutions are accomplished with
Smoothed
Particle Hydrodynamics
SPH technique using a pc cluster. For dam break flow
impact against the obstacle, the flow impacts on the vertical wall at t = 0.8 sec, at time t = 1.2 sec an
upward water jet is suddenly formed and over- turning wave with an adverse momentum is
observed at t = 1.3 sec. Impact pressure flow on a wall of the obstacle is 2.39 Nm2 and velocity in y
direction is 4.32 msec. Regarding dam break flow impact against obstacle-clearance, high velocity
and shallow water depth flow are happened in x- direction at t = 0.35 sec. The two flow face each
other and this two flow impact the vertical flow then simulate a splash. This happened at t = 1.1 sec.
The established SPH model is able to capture over- turning wave phenomena and splash phenomena.
Keywords: Dam Break, Smoothed Particle Hydrodynamics, Obstacle, Obstacle-clearance.
1 INTRODUCTION
1.1 Motivation
Kategori