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Energy & Fuels 2003, 17, 1014-1021
Control of Agglomeration and Defluidization Burning High-Alkali, High-Sulfur Lignites in a Small Fluidized Bed CombustorsEffect of Additive Size and Type, and the Role of Calcium S. P. Bhattacharya* and M. Harttig Cooperative Research Centre for Clean Power from Lignite, 8/677 Springvale Road, Mulgrave, Victoria 3170, Australia Received September 17, 2002. Revised Manuscript Received February 19, 2003
This paper presents results of an experimental study to assess the effects of type and size of additives on control of agglomeration and defluidization during combustion of high-alkali, highsulfur lignites. It was established in a previous study that additives such as clay-based minerals could control agglomeration and defluidization during combustion of a high-sulfur coal. Analysis of the data suggested that the agglomerating compounds were condensing on the fine additives, which were elutriated from the bed. The current work has tested this hypothesis in a laboratoryscale fluidized bed. Two South Australian lignites with high alkali, chlorine, and sulfur contents were burnt at temperatures of 800 °C and 850 °C with and without additives in a silica sand bed. The additives included two grades of fine silica sand, calcined alumina, and fly ash. From physical observation during the tests and from chemical analysis and electron microscopy after the tests, it was found that particle size, as well as type of additives, is also important in controlling agglomeration and defluidization. Any additive which is of fine size and itself is not a low-meltingpoint compound can potentially control defluidization in a fluidized bed combustor. Fine additives provide large surface areas and capture the fine ash or agglomerate-forming constituents, which are elutriated from the bed, thereby controlling agglomeration and preventing defluidization.
Introduction South Australia has large reserves of high-moisture (>60% as-received) lignites. These have high levels of sodium, chlorine, sulfur, calcium, and magnesium. These are currently not used for power generation in conventional pulverized-fuel-fired furnaces as these are likely to result in unacceptable fouling. Circulating fluidized bed combustion (CFBC) systems offer a potential solution to these problems. CFBCs are known to burn a wide range of fuels, maintain combustion temperatures below ash fusion point (800-900 °C), control SO2 emission by using in-bed sorbents, and control NOx emission by using lower combustion temperatures and air staging. But CFBCs also have disadvantages. Depending on the operating conditions (temperature in particular), agglomerates may form in the combustor as a result of high content of low-meltingpoint inorganic matter in some lignites. In the worst case, the entire bed may defluidize as a result of the presence of large agglomerates. Bhattacharya et al.1 conducted combustion tests on three Victorian and one South Australian lignite, and one char (from a Victorian lignite) in an atmospheric CFBC pilot plant (430 mm diameter), capable of burning raw lignites (62% moisture) up to 100 kg/h. The three Victorian lignites and the char could be burnt without * Corresponding author. E-mail:
[email protected]. (1) Bhattacharya, S. P.; Kosminski, A.; Yan, H.; Vuthaluru, H. Proceedings of the FBC Conference, 2001, Nevada.
any problem in the CFBC for the designated duration of 120 h at 800 °C bed temperature. However, the South Australian lignite (Lochiel coal) could be burnt only for 30 h before significant bed agglomeration and solid recirculation problems forced the tests to be abandoned at 800 °C. It was established from chemical analysis and electron microscopy that the release of compounds (mainly sulfates) of calcium, sulfur, magnesium, and sodium from the coal and their physical interaction with the bed materials (silica sand, ∼200 µm) caused growth of particles, poor fluidization, and bed agglomeration. The presence of chlorine in the form of sodium chloride aggravated the problem by forming low-melting-point eutectics. This lignite has significant proportions of sodium, calcium, magnesium, sulfur, and chlorine, as shown in Table 1. Subsequently, two tests, each exceeding 120 h duration, could be performed using additives of fine size. Dolomite and a clay mineral were used separately as the additives in these tests for agglomeration control. Although these minerals have vastly differing compositions, both were found to be effective in agglomeration control. Both minerals, however, were finely divided and of similar particle size. Analysis of the data suggested that the agglomerating compounds were condensing on the surface of the fine additives, which were elutriated from the bed. Linjewile and Manzoori2 evaluated the role of four additives (dolomite, two kaolinite claysscode-named CW clay and DV clay, and hydrated alumina) in
10.1021/ef020205o CCC: $25.00 © 2003 American Chemical Society Published on Web 06/25/2003
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Table 1. Analysis of the Coals Used Lochiel Bowmans moisture, air-dried[%] ultimate analysis DB [wt %] carbon hydrogen nitrogen oxygen sulfur chlorine ash ash composition [wt %] SiO2 Al2O3 Fe2O3 MgO Na2O CaO SO3 K2O LOI
Ca-exchanged acid-washed Lochiel Lochiel
27.1
18.2
19.9
14.2
59.8 4.5 0.48 17.69 3.4 0.63 13.5
58.3 4.5 0.47 18.23 4.9 1.6 12.0
61.3 4.5 0.44 19.16 3.3 0.1 11.2
64.4 4.7 0.5 23.41 3.3 0.03 3.6
21.7 7.1 4.9 11.4 9.4 12.4 31.5 0.3 1.0
8.2 6.5 8.0 13.9 18.6 3.4 38.9 0.12 2.2
13.5 4.7 11.1 3.3 1.7 26.2 34.1 0.04 0
70.9 11.6 7.3 1.1 0.47 1.8 3.0 0.14 1.1
agglomeration control during combustion of Lochiel coal in the same combustor used in this study. Although they found all four to be effective in controlling agglomeration, aluminum hydrate was found to be the most effective. This was believed to be a result of its large internal surface area, which might have been able to absorb the molten ash (from coal combustion). When dolomite was used, it formed calcium sulfate and diluted the molten agglomerating species. DV clay also formed solid ash material, presumably due to the incorporation of clay particles in the ash, which reduced the concentration of the agglomerating species in the bed. CW clay reduced the deposition of ash on the bed materials by fixing the sodium (agglomerating) species of ash into solid phases. No information is available on the particle size of the four additives used in the study. It is unclear whether particle size of the additives played any role in controlling agglomeration. The present study was, therefore, undertaken to demonstrate the effect of the size of additive particles on agglomeration and defluidization. Clay-type minerals were deliberately excluded to ensure that the known influence of the material’s properties did not influence the test results. The role of calcium on agglomeration was also investigated. Experimental Section Experimental Setup. Tests were carried out in a laboratory-scale spouted fluidized bed combustion system, made from a cylindrical stainless steel column with a conical base. The column has an inner diameter of 76.2 mm, a height of 1030 mm, and an inlet at the bottom of the conical base, 25.4 mm in diameter. A removable 300 µm screen is mounted on the inlet and acts as a distributor. Five thermocouples are fitted on the wall and the conical section to measure the temperature profile. The three thermocouples at the bottom are used to calculate the average bed temperature. The system also has two pressure taps for measuring the pressure drop across the bed. The top of the column is covered with a piece of quartz glass through which the fluidization in the bed can be observed. Coal is fed using a screw feeder, the speed of which (2) Linjewile, T. M.; Manzoori, A. R. Role of additives in controlling agglomeration and defluidization during fluidized bed combustion of high-sodium, high-sulphur low-rank coal. Proceedings of the Engg. Found Conference, Hawaii, November 2-7, 1997.
Figure 1. Schematic of the experimental setup. can be varied to achieve different feed rates. The bed temperature is maintained by adjusting the temperature of the fluidizing air. The fast fluidization velocity and the internal recirculation of the bed material provide conditions characteristic of CFBC systems. This rig has previously been used for combustion work2-4 involving South Australian lignites. The feeder is water-cooled to prevent any ignition of the coal within the feeder. The test-rig had no cooling tubes inside the combustor, but the hot flue gas is cooled along the horizontal path to the cyclone. A schematic diagram of the combustion system is shown in Figure 1. Coals. The proximate and ultimate analyses of the coals used in this study are given in Table 1. Lochiel and Bowmans, which are South Australian lignites with high levels of sodium, chlorine, sulfur, calcium, and magnesium, were selected because these are known to cause agglomeration problems in fluidized beds.1,2,4 In addition, acid-washed and calciumexchanged Lochiel coals were used in the study to demonstrate the effects of the inorganics present in the coal on agglomeration. In their as-received forms, the coals had about 62% moisture. Before testing, these coals were crushed, air-dried, and sieved to 0.85-4 mm particle size. Acid-washed coal was prepared by using air-dried Lochiel coal soaked in 3 M HCl solution for 72 h, then washed with demineralized water until little or no chlorides were measured. Calcium-exchanged coal was prepared by soaking the acid-washed coal in 0.5 M Ca acetate solution for 48 h. Bed Material and Additives. The bed material for all tests was silica sand in the size range of 0.5-0.85 mm. The inorganic components of the bed and additive materials used in the tests are given in Table 2. The particle-size range of these materials is shown in Table 3. The high loss on ignition (LOI) in the case of dolomite is mainly a result of the decomposition of calcium and magnesium carbonate at 600 °C. As already indicated, clay minerals (aluminosilicate) were deliberately excluded as additives in order to examine the influence of particle size free of any influence of the material properties, as was established by Linjeweile and Manzoori.2 Fine and coarse silica sand were chosen to examine the effect of particle size (of additives) on bed agglomeration. Both had similar chemical composition. The size of the coarse silica sand was chosen so as to ensure that these remained fluidizable at (3) Manzoori, A. R.; Agarwal, P. K. The role of inorganic matters in coal in the formation of agglomerates in circulating fluidized bed combustors. Fuel 1994, 72, 1069-1975. (4) Vuthaluru, H. B. Control methods for remediation of ash-related problems in fluidized-bed combustors. Fuel Proc. Technol. 1999, 60, 145-156.
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Table 2. Analysis of the Bed Material and Additives Used silica sand SiO2 Al2O3 Fe2O3 MgO CaO Na2O SO3 K2O TiO2 LOI
99.79 0.21
fly ash 32.85 22.35 4.1 9.2 9.45 7.75 9.75 0.49 1.08 2.98
calcined alumina
dolomite
0.03 98.5 0.02 0.6 0.85 0.85
2.0 0.6 0.7 20.4 30.7 0.2 1.1 0.09 0.04 44.17
aluminum hydrate 1.73 94.7 0.06 0.03 0.14 1.35 0.08 0.02 0.15 1.74
Table 3. Particle Size of Bed Materials and Additives material
used as
size [mm]
silica sand silica sand, coarse silica sand, fine alumina hydrate fly ash dolomite calcined alumina
bed material additive additive additive additive additive additive
0.5-0.85 0.85-1 0.15-0.25 0.075-0.15 0.06-0.1 0.08-0.2 0.075-0.15
the air flow-rates used. The other additives were chosen to determine any effect of additive type (composition) on bed agglomeration. The fly ash was from a Lochiel coal test at 800 °C in the CFBC test facility mentioned earlier1 in the Introduction. Test Procedure. A compressor supplied combustion air, which is also the fluidizing gas. The airflow rate in the fluidized bed was maintained around 100-120 L/min. The coal feeder was calibrated before each test, as feed rate is a function of the type of coal, coal additives, and their size. Additives were premixed with the coal. Approximately 200 g of bed material was added into the rig by pouring through the top. Fluidizing air was adjusted to obtain the desirable flow rate after turning on the electrical heater. Coal feed started once the bed temperature reached 600 °C. Feed rate of coal was maintained closely around 350 g/h. Bed temperature was maintained by controlling the temperature of the fluidizing air. Bed material and fly ash from the cyclone was collected after each test. Tests and Operating Conditions. A total of nine tests were conducted. The majority of the tests centered on Lochiel coal, as it was found to agglomerate unless an additive was used during trials in a large CFBC test facility. As these tests were intended to assess only the effect of the type and size of additives, their feed rate was arbitrarily chosen as 15% of the coal feed rate. No attempt was made to optimize the feed rate. While the nonadditive tests were performed at 800 °C, the additive-based tests using the Bowmans coal were conducted at 850 °C to examine the effects of the additives at higher temperature. Analysis Used. Samples of the coals used in the tests were analyzed for moisture content, ash yield, ultimate analysis, and ash composition. Original bed and additive materials were analyzed for their composition and size. Spent bed material and fly ash from the tests were subjected to the following tests: • Chemical analysis. • X-ray diffraction (XRD) on bed coatings to identify the crystalline phases formed from the interaction of the bed materials with the inorganic matter in coal. The coatings were carefully separated from the bed particles by hand-grinding using a mortar and pestle. The samples were then pressed into aluminum sample holders for X-ray diffraction analysis. XRD patterns were recorded with a Philips PW 1800 microprocessor-controlled diffractometer using Co KR radiation, a variable divergence slit, and a graphite monochromator. The diffraction patterns were recorded in steps of 0.05° 2θ with a 1.0 s counting time per step.
Table 4. Operating Conditions
test
coal type
additive
1 2 3 4 5 6
Lochiel Lochiel Lochiel Lochiel Bowmans Ca-exchanged Lochiel acid-washed Lochiel Bowmans Bowmans
none fine silica coarse silica aluminum hydrate none none
7 8 9
feed rate [% of coal feed] 15 15 15
average bed temperature [°C] 800 800 800 800 800 850
dolomite
15
850
calcined alumina fly ash
15 15
850 850
• Spot analysis and X-ray mapping of coated bed particles mounted in an epoxy block, surface-polished, and coated with carbon. The electron microprobe JEOL 8900R Superprobe equipped with an energy-dispersive X-ray analysis system and chemical imaging software was used. The accelerating voltage was 15 kV, and the beam current was 0.0325 µA. Other analyses included scanning electron microscopy (SEM) of fly ash retrieved from the cyclone for morphology assessment, and thermogravimetric analysis (TGA) and differential thermal analysis (DTA) on bed coatings to determine their thermal behavior. Thermochemical calculations were also carried out to compare the theoretical predictions of formation of various phases with results from XRD analysis.
Results and Discussion Test Duration and Physical Observation. The intended duration of each test was a maximum of eight hours unless terminated as a result of bed agglomeration or mechanical problems. The duration achieved for each test is shown in Table 5. During Test 1, a ring of agglomerated bed material was observed to form on the combustor wall 30 min after commencing coal firing. Located 10 cm above the feeding point, it reduced the cross section by about 15%. After 190 min of coal firing, the bed defluidized. Bed materials collected after the test showed a light-beige-colored coating. During Test 2, no deposits were observed and there were minimum fluctuations in temperature, which was easier to control. The system was shut down after approximately 7 h, although there was no sign of defluidization at that stage. The bed particles at the end of the test had a thicker coating and the color was slightly darker than in Test 1. During Test 3, after 220 min a ring of agglomerated bed material formed on the wall near thermocouple 2, blocking up to 80% of the cross section. Eventually, the bed defluidized 235 min after commencement of coal firing. The agglomerated particles fell apart while emptying the cooled furnace. These bed particles were covered with a light-beige-colored thin coating (presumably due to the shorter duration of the test). It was ensured beforehand that the size range of the coarse silica sand used as an additive in test 3 remained fluidizable under test conditions. The most widely used correlation for the minimum spouting velocity (Ums) at ambient conditions for spherical particles is the MathurGishler equation.5 This correlation is known to be inadequate for hydrodynamic conditions in a spouted bed at high temperature, particularly for coarse and (5) Mathur, K. B.; Gishler, P. E. AIChE J. 1955, 157-264.
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Energy & Fuels, Vol. 17, No. 4, 2003 1017
Table 5. Duration Achieved of Each Test
test
coal type
additive
average bed temperature [°C]
1 2 3 4 5 6 7 8 9
Lochiel Lochiel Lochiel Lochiel Bowmans Ca-exchanged Lochiel acid-washed Lochiel Bowmans Bowmans
none fine silica coarse silica aluminum hydrate none none dolomite calcined alumina fly ash
800 800 800 800 800 850 850 850 850
duration achieved minutes 190 410 235 420 235 480 182 420 330
defluidized(?) yes no yes no yes no no no no
Table 6. Phases Identified in the Coatings and Fly Ash phase
formula
phase
formula
albite anhydrite augite forsterite goethite halite hematite lime magnetite, maghemite magnesite
NaAlSi3O8 CaSO4 Ca(Mg,Fe,Al)(SiAl)2O6 Mg2SiO4 FeOOH NaCl Fe2O3 CaO Fe3O4 MgCO3
merwinite monticellite nepheline nosean periclase portlandite pyrophyllite quartz sodium sulfate thenardite
Ca3Mg(SiO4)2 CaMgSiO4 NaAlSiO4 Na8(Si6Al6)O24(SO4)‚H2O MgO Ca(OH)2 AlSi2O5(OH) SiO2 Na2SO4 Na2SO4
sticky particles (He6). He6 also measured the minimum spouting velocity at temperatures up to 700 °C for several size groups of silica sand particles (including the size group in this study) with ash coatings from the Bowmans and Lochiel coals using the same rig as for this study. The Ums for coated sand (0.85-1.4 mm coated size, 0.85-1.0 mm original size) at 700 °C was measured to be around 0.45 m/s. For the current tests, the gas velocity in the combustion zone at 800 °C was chosen to be 1.58 m/s or higher. In Test 4 with fine alumina hydrate as additive, there was no sign of agglomeration after 7 h. Also, there were minimal temperature fluctuations during the test. The bed particles at the end of the test appeared to have coating thickness and color similar to those from Test 2. In Test 5 with Bowmans coal, the bed defluidized after 235 min. The bed particles had a thin coating, which was colored red and dark brown. In Test 6 with calcium-exchanged Lochiel coal, there was no sign of defluidization during the 7 h of testing. The bed material after the run had a very thin coating, which was quite red in color. In Test 7 with Bowmans coal and calcined alumina as additive, there was no sign of defluidization during the 7 h of testing. The coating on the bed material at the end of the test was dark brown in color, and was similar in color and coating thickness to that of Test 5. In Test 8 with the Bowmans coal and fly ash as additive, there was no sign of defluidization when the test was stopped after 51/2 h because of mechanical problems. The coating on the bed material collected after the test had a light-brown color and thickness similar to that in Test 7. The acid-washed Lochiel coal used in Test 9 appeared to ignite quickly. The bed particles collected after the test showed almost no coating, and the color was only slightly different from that of the original bed material. (6) He, Y. Characterisation of spouting behaviour of coal ash with thermo-mechanical analysis. Fuel Proc. Technol. 1999, 60, 69-79.
There was no sign of defluidization when the test was terminated after 182 min because of a mechanical problem of the feeder. Salient observations from the tests are summarized below: • All of the additives used during the tests, irrespective of their chemical composition, were effective in controlling defluidization, as long as these were of fine size. This was observed during tests with both Lochiel and Bowmans coal. • In the tests where defluidization occurred, there was more evidence of agglomeration. • The Bowmans coal test without additive could not be continued beyond 235 min at 800 °C. However, use of fine additives of fly ash or calcined alumina allowed tests to be continued, even at a higher temperature of 850 °C, for longer times of 330 min and 420 min without defluidization. • There was no defluidization during the test involving acid-washed Lochiel coal and Ca-exchanged Lochiel coal. X-ray Diffraction (XRD) of the Bed Coatings and Fly Ash. The phases found in the coatings and fly ash samples are listed in Table 6. It should be noted that amorphous compounds and compounds forming a weak crystalline structure cannot be detected by XRD. The following classifications have been used in describing the concentration of phases detected: dominant >60%; Co-dominant-sum of phase >60%; sub-dominant, 20-60%; minor, 5-20%; trace, 60%) found in fly ash for all tests. • For all of the Bowmans coal tests, chlorine was detected in the bed material. For the Lochiel coal tests, chlorine could be found only in the fly ash, except for test 1 (Lochiel coal without additive) and test 3 (Lochiel coal-coarse silica); in both cases, the bed defluidized. • An increase in the aluminum content in the bed material had no apparent effect. In the case of test 3 (Lochiel coal-coarse silica), the aluminum content was higher than in test 2 (Lochiel coal-fine silica). However, in test 3, the bed defluidized, but in test 2, the bed remained fluidized. Mechanism of Agglomeration and Its Control. It appears that the release of compounds (mainly sulfates) of Ca, S, Mg, and Na from the coal and their physical interaction with the bed materials caused bed agglomeration during the tests. The presence of chlorine in the form of NaCl, which was found in almost all agglomerates, aggravates the problem by forming lowmelting-point eutectics).3,8 On the basis of observation and the discussion in the previous sections, agglomerate formation during the tests is believed to have proceeded in the following steps: (1) A low-melting-point eutectic comprised of sulfates of sodium, magnesium, and calcium (and sodium chloride in some cases) deposits on the surfaces of the bed particles. (2) Individual particles grow in size due to the eutectic coating. Particles adhere to each other to form small agglomerates which may generate larger agglomerates. Poor fluidization conditions occur when the fraction of enlarged particles becomes excessive. This mechanism is similar to that proposed by Manzoori and Agarwal,3 and Mann et al.7 One way to control agglomeration is to elutriate the agglomerating constituents away from the hot bed as soon as these are released during combustion. This
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Figure 3. Distribution of inorganic elements in bed material and fly ash.
occurs when finely divided additives are admitted into the fluidized bed. Any additive which is of fine size and which itself is not a low-melting-point compound can potentially control agglomeration and defluidization in a fluidized bed combustor. Fine additives provide large specific surface areas to capture the agglomerateforming constituents, which are then elutriated from the bed, thereby controlling bed agglomeration and preventing defluidization. This is why little agglomeration and no defluidization occurred when fine additives (all of differing composition, and none of which are clay, which is a known agglomeration preventer) were used. As previously indicated in Section 1, the same effect was observed during combustion trials on Lochiel coal in a CFBC pilot plant, where two additives of different compositionsdolomite and a clay mineral, but which were finely divided, were found to be effective in controlling agglomeration. On the other hand, coarse additives (such as coarse silica used in test 3, in which the bed defluidized) provide a smaller specific surface area, and present a smaller capacity to capture agglomerating constituents. This results in a gradual growth of the bed inventory of coarse particles, eventually leading to defluidization unless the bed is drained periodically. Role of Calcium. It is important to briefly discuss the effect of Ca in coal on agglomeration. There was no defluidization during the test involving acid-washed Lochiel coal (with dolomite) as most of the inorganics were lost during acid-washing. The use of dolomite, which is a calcium- and magnesium-rich mineral, resulted in the formation of anhydrite, i.e., calcium sulfate. Similarly, during combustion of Ca-exchanged Lochiel coal, defluidization did not occur. Calcium was
found to produce mainly anhydrite (calcium sulfate with a melting point ∼ 1400 °C), which is not a sticky compound at the temperatures of the fluidized bed. Results from these two tests indicate the role of calcium on agglomerationsits mere presence does not induce agglomeration, i.e., the presence of other inorganics is required to induce agglomeration. However, it can result in a growth of the bed particles and an increase in the inventory of large particles, which may lead to defluidization unless the bed is periodically drained. Implications for Large-Scale Rigs. This study is intended only to demonstrate that the particle size rather than the type of additive can be important in controlling agglomeration. The feed rate and particle size of the additives were not optimized during this study. The type of additive to be used in large-scale operation will depend largely on its availability and cost. Several additives, such as clay minerals, fly ash, or overburden materials, are potentially suitable for use in large-scale units. While fly ash is readily available (and cheap), its continuous use may not be sustainable because of its enrichment of the inorganic species during recycling. However, it can be used intermittently with other additives (such as fine clay particles), thereby reducing the usage of such additives and also enhancing the utilization of the additives/SO2-sorbents present in fly ash. Conclusions An experimental study was undertaken to assess the effects of type and size of additives on control of agglomeration and defluidization during combustion of two high-alkali, high-sulfur lignites. Deposition of ash
High-Alkali, High-Sulfur Lignites in a CFBC
coating on the bed materials is observed to be a physical phenomenon, with a clear boundary separating the coating from the bed material being evident. Defluidization of the bed is independent of the coating thickness on the bed particles. Some particles from the defluidized tests had less coating than particles from nondefluidized tests. Agglomerates form as a result of sticky, lowmelting-point eutectics of sulfates of sodium, magnesium, and calcium depositing on the particles. Other eutectics also form from silicates and sulfates of sodium. In some cases, a small amount of sodium chloride (halite) was also detected in the ash coatings. One way to control agglomeration is to elutriate the elements/compounds causing agglomeration from the bed. The combustion of both Lochiel and Bowmans coal without additives resulted in defluidization. The use of fine additives (silica sand, aluminum hydrate, calcined alumina, and fly ash) all prevented defluidization,
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irrespective of their composition. Defluidization occurred, however, when coarse silica sand was the additive. Fine additives provide large surface areas to capture the fine ash or agglomerating constituents. These are then elutriated away from the bed, thereby preventing defluidization. This indicates that, in principle, use of any additive, which is of fine size and which itself is not a low-melting-point compound, could control agglomeration in a fluidized bed combustor. Acknowledgment. Financial support for the work was received from the Cooperative Research Centre for Clean Power from Lignite which is established under the Cooperative Research Centre program of the Commonwealth of Australia. EF020205O
