ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY

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1 Paper No. 572 ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY N Murthy 1, * and K Basavaraj 2 ABSTRACT The quality of iron ore fines in terms of high iron content and low levels of deleterious impurities such as Silica, Alumina, Sulphur and Phosphorous is a critical parameter, in sintering and subsequent iron and steel making processes. As the higher-grade ores become depleted, there will be a stronger focus on treating lower-grade haematite/goethite ores and developing suitable beneficiation techniques to reduce the levels of impurities. Innovative flow sheets, based on new and commercially available technologies, is required. These will be needed to include gravity concentration devices, which can handle coarse and fine feed sizes. In this paper, efforts made to reduce the silica and alumina content of a low grade iron ore fines (<1.0 mm size) sample from the Pilbara region in Western Australia are described. The feed sample, a goethite abundant lower grade iron ore fines, which was a plant reject assaying 48.66% Fe with 13.61% SiO 2 and 5.09% Al 2 O 3 was investigated. To this end, an experimental campaign was undertaken, and beneficiation studies were conducted on the sample using a Floatex Density Separator (FDS), a gravity device which can be operated for size classification and/or relative density separation. The objective was to produce high-quality iron ore material suitable as sinter feed. An iron concentrate with a grade around 57.0% Fe (Calcined Fe of about 63.0%) was achieved while recovering around 67.0% of the feed weight. In addition, a rejection of substantial content of Silica (>75%) and Alumina (>66%) was achieved while securing >77% iron recovery. On the other hand, sharp classification efficiency with low values of imperfection around 0.20 was obtained. Consequently, the response of the lower grade iron ore sample to FDS application, has vast potential to reject deleterious impurities as a single stage separating beneficiation equipment. Remarkably, it was demonstrated, that a great amount of goethite, abundant in lower grade iron ore fines/plant rejects, which are currently being either stockpiled and/or dumped as waste, can be treated using FDS application and potentially can add a significant value to the iron ore mining industry by recovering additional iron ore fines. Keywords: deleterious impurities, beneficiation techniques, classification, relative density INTRODUCTION separation Global demand for iron ore products in steelmaking is increasing, mainly because of ongoing developmental activities in Asian countries. In contrast, most reserves of direct shipping ore have now been depleted. Currently, the mining industry s emphasis is on the development and selection of appropriate beneficiation, combination 1. CSIRO Process Science and Engineering, Box 883, Kenmore, QLD 4069, Australia. Nunna.Murthy@csiro.au 2. CSIRO Process Science and Engineering, Box 883, Kenmore, QLD 4069, Australia. Basavaraj Karadkal@csiro.au XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

2 MURTHY AND BASAVARAJ methods to treat lower grade iron ores and to produce concentrates from such ores, which are acceptable as feedstock for the blast furnace. The lower grade iron ore deposits in Pilbara region of Australia contain hydro haematite and goethite varieties as the most abundant iron oxides, which are associated with a varying degree of complex Gangue minerals. A number of publications have shown, that most of the lower grade formation-hosted iron ore deposits from this region in Western Australia are soft and friable in nature and are typically complex (Morris, 1980,Taylor et al, 2001,Tompkins and Cowan, 2001,Clout 2006). Further, during mining, handling and processing, considerable quantity of fines are generated. These lower-grade iron ore fines are typically rich in Alumina and Silica. Furthermore, the mineralogical associations and liberation size characteristics of individual iron ore deposits are critical to the selection of appropriate process technologies and equipment for specific particle size ranges (Murthy and Karadkal, 2011). Therefore, the reduction of the levels of these Gangue minerals by physical separation techniques is a challenge, and alternate models and approaches based upon mineralogical associations are currently being examined. At present, some of the commercial beneficiation plants use hydrocyclones to deslime the lower grade iron ore material, and this usually achieves, substantial rejection of the alumina bearing clayey minerals. But, hydrocyclones are inherently inefficient in classifying relatively close range dense particles due to misplacement of the heavy iron ore minerals. Most processing plants never exceed the 60% separation efficiency level (Barrios, 2009). On other hand, gravity concentration using spirals is another processing option (Wills and Napier-Munn, 2006) of interest. Again, despite their advantages, spirals are limited by an inability to achieve the desired final product grade in a single stage. This is a result, of the loss of some of the valuable heavier minerals to the Gangue minerals as well as the entrainment of Gangue minerals to the concentrate. In addition, the complexity of the feeding system of the multiple-stage spiral circuits used, often requires extensive maintenance to arrest mineral losses due to slurry spillages. In contrast, substantial work has been done to describe the particle separation in up-current classification (UCC) techniques using various designed teeter bed separators (Asif, 2004,Galvin et al, 1999a, 1999b, Sarkar et al, 2006, 2008a, 2008b). It is well established, that in a teeter bed separator, both the density and size play significant roles while separating minerals. The Floatex Density Separator (FDS) is a teeter bed separator, using an UCC technique that has the potential to upgrade lower grade iron ore fines and is a useful technique for rejection of clayey and/or silicate minerals. The ease and efficacy of separation in the FDS has attracted considerable interest in the mineral industry and academia. The heavier particles settle against a rising current of water through a bed acting as an artificial heavy medium. Also, the teetering bed and the hindered settling zone offer more resistance to settling particles. The combined effect of teetering bed and simplified rising water current distribution system of the FDS, makes it possible, to increase the separation efficiency while minimising the possible misplacement of heavier minerals in the overflow stream. In this work, the applicability of a FDS to concentrate lower-grade iron ore fines from the Pilbara region in Western Australia was investigated. The main purpose of this study, was to develop a technically feasible beneficiation route using FDS, and to analyse its performance for treating difficult-to-treat iron ore types. The extent to which yield, the underflow was affected by the associated ore mineralogy and the process control variables are discussed. EXPERIMENTAL Feed material characterisation A representative subsample was submitted for chemical analysis, results are given in Table 1. The as received sample assayed 48.66% Fe with 13.61% SiO 2, 5.09% Al 2 O 3 and 9.96% LOI. Other components such as P, S, K 2 O, Na 2 O, Zn were within typical iron ore specifications. In addition, the particle size distribution and chemical analysis of each size fraction was determined. The size-by-size analysis is shown in Table 2. Figure 1, illustrates the trend in the Fe, SiO 2 and Al 2 O 3 distribution by size. It was found, that in the coarser size fractions, the levels of Iron, Alumina and Silica remain more or less uniform. But, the ultra fine fractions are quite lean in iron content and rich in Alumina and Silica. Also, data reveal that the sample contained about 60 percent of material below 212 µm with high alumina and silica content. XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

3 ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY Table 1. Chemical analysis and specific gravity of the feed sample Component Assay (%) Component Assay (%) Fe P SiO S Al 2 O Zn 0.01 TiO K 2 O Mn 0.09 Na 2 O CaO 0.43 LOI* 9.96 MgO 0.53 SG (g/cm 3 ) = 3.85 Table 2. Size-by-size analysis of the feed sample Size (µm) Weight (%) Assay (%) Fe SiO 2 Al 2 O 3 LOI Head* Calculated split at 25 µm Microscopic and Electron probe micro analysis (EPMA) studies on the as received representative sample were carried out, to determine mineral identification and elemental distribution in the minerals. Representative photomicrograph of characteristic ore textures are shown in Figure 2. The ore sample is characterized by a range of minerals including, hard, dense and soft-medium, porous hydrohaematite, hard, dense vitreous goethite, porous, medium-hard earthy goethite, soft-medium, porous ochreous goethite, ochreous goethite with kaolinite infill, kaolinite, and fully liberated quartz. Figure 3 illustrates the elemental distribution in the minerals as determined from the EPMA studies. It is evident from the results, that minerals such as ochreous goethite with kaolinite infill, kaolinite and fully liberated quartz are distributed to various degrees from coarse to fine size fractions. The degree of liberation of iron bearing and Gangue minerals was found, to be increased with decreasing size and hence the ultra fines are rich in Alumina and Silica but also contain significant iron levels due to the presence of ochreous goethite with kaolinite infill material. XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

4 MURTHY AND BASAVARAJ Figure 1. Size-by-size distribution of Fe, SiO 2 and Al 2 O 3 in the feed sample Figure 2. Optical photomicrograph of the feed sample showing typical ore minerals occurrence. (h: hard, dense and soft-medium, porous hydro haematite, v: hard, dense vitreous goethite, e.g : porous, medium-hard earthy goethite, og: soft-medium, porous ochreous goethite, og-k: ochreous goethite with kaolinite infill, k: kaolinite, q: quartz). XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

5 ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY Figure 3. Elemental distributions by mineral as determined by EPMA for the feed sample. (h: hard, dense and soft-medium, porous hydro haematite, v: hard, dense vitreous goethite, e.g. : Porous, medium-hard earthy goethite, og: soft-medium, porous ochreous goethite, o Equipment description The experimental campaign was carried out, using a FDS laboratory model (Model No. LPF-0230, supplied by Outotec) which had a 230 mm X 230 mm square cross section, a 530 mm high tank with a 200 mm high inverted conical dewatering section at the lower end. The main feed distributor is at the top of the tank, which is centrally located, and this sets to distribute material inside the tank at about 230 mm from the top. The feed slurry is introduced through this well. The equipment can be divided in to six main zones viz. Overflow collection, upper intermediate, feed, lower intermediate, thickening, and under flow collection zones. A schematic of the FDS, a diagram showing the zones of importance, and a cut away view of the FDS are presented in Figure 4. Figure 4. Schematic diagram of FDS (a), zones of importance in the FDS (b), and a cut away view of the FDS (c) XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

6 MURTHY AND BASAVARAJ The lower intermediate zone between the feed inlet and teeter water addition plays a key role in separating minerals. In this zone, heavier particles settle against a rising current of water, thus fluidizing the material and forming a teeter bed which offers more resistance to the settling particles. Teeter/fluidisingwater is introduced to the lower intermediate zone chamber, through evenly spaced water distribution pipes, thus forming several small reaction chambers in the lower intermediate zone. Furthermore, this FDS is equipped with a pressure sensor mounted in the lower intermediate zone above the teeter water port distribution pipes integrated with a process controller looped with the discharge control valve. This instrumentation helps to maintain a constant height for the teeter bed and a steady discharge from the underflow. Methods Prediction and several mathematical descriptions of FDS performance have been given by a few researchers (Galvin et al, 1999a, 1999b, Sarkar et al, 2006, 2008a, 2008b). However, most of these have limited applicability. Also, detailed experimental results have not been compared with the predictions in many cases. In this case study, difficult-to-treat ore material is investigated by continuous testing with FDS which involved careful selection of process operating conditions to achieve the maximum possible iron grade and recovery. The key focus was to maximize rejection of alumina and silica content with minimal loss of iron content. Selection of experimental conditions The key operating variables, selected in this study, use feed pulp density, teeter water flow rate, feed rate and the bed pressure, since the FDS equipment enables to both classify and concentrate. Based on a brief survey of operating plants requirements, a feed pulp density of 35% solids by weight was selected. A number of dummy trials were undertaken to adjust the feed rate, bed pressure and teeter water flow rates to keep fluidization in the bed whilst periodically verifying the iron losses in the over flow. It was observed, that the interface between feed zone and lower intermediate zone (at bed levels ~50 to 100 mm below the feed well distributor), plays a key controlling role for this type of ore treatment by keeping materials, being separated at reduced turbulence to avoid ore mineral misplacement in the upstream. Hence, maintaining a bed level sufficiently below the feed well distributor and not crowding with feed rate proved to be critical for effective separation. Additionally, maintaining fluidization with the teeter water additions was also important in achieving steady operation. On the whole, the experimental conditions range, for treatment on this type of lower grade iron ore fines were found to be as follows: Bed pressure range of to bar. Teeter water flow rate of 6.0 LPM to keep bed in teetered/fluidised state for the above range of bed pressures. Feed rate range of 600 to 750 kg/h to realize reduced turbulence at the interface of the feed and lower intermediate zones. Accordingly, two different sets of operating conditions were selected to assess the performance of the FDS with this type and these are given in Table 3. Table 3. FDS test experimental conditions Operating Variable Case-1 Case-2 Teeter Water Flow Rate (LPM) Feed Rate (Kg/h) Feed Pulp density (%solids by Wt.) Bed Pressure (Bar) Bed level below feed well (mm) ~650 ~700 ~35 ~ ~60 ~100 XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

7 ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY RESULTS AND DISCUSSION Feed characterisation was carried out in terms of chemical analysis, and side-by-side chemical, microscopic and electron probe micro analysis for identifying distribution of mineral values by size and for understanding elemental distribution in the minerals. The as received -1.00mm feed material contained silica and alumina at high levels (13.61% SiO 2 and 5.09% Al 2 O 3 ). In addition, from the size-by-size analysis shown at Table 2, it is evident, that more than 60 percent material is less than 212 µm in size and had a P 80 of 442 µm. Moreover, calculated results from the size-by-size analysis reveal that classification by size at 25 µm will likely produce high silica and alumina containing products. Therefore, size-by-size analysis clearly indicates, that ultrafine sizes less than 212µm in size are lean in iron content while rich in silica and alumina content. On the other hand, Microscopic and Electron probe micro analysis confirmed that the feed sample is composed of hydrohaematite-goethite minerals associated with vitreous, earthy and ochreous goethite types of iron ore minerals while the Gangue minerals are ochreous goethite with kaolinite infill, kaolinite, and quartz and these are more predominant at and below 212 µm. In fact, minerals specific gravity in the feed, is the primary basis of separation and concentration, additionally size also plays a critical role. Since, both the specific gravity and size of the material together are the factors for effective suspension density in an UCC technique, and for the separation of the near gravity materials, without misplacement of ore mineral values in to the tailings and rejecting deleterious impurities, requires an investigation and assessment. Again, separating tank design and controls of liquid velocity will have a substantial influence on separation of valuable minerals from such difficult-to-treat iron ore fines. To this end, assessing the performance of a FDS for the recovery of iron from low-grade Australian iron ore fines was undertaken. Accordingly, based on several trial runs with FDS, two different sets operating conditions were selected as shown in Table 3 for assessing its performance. The results of continuous treatment of this sample using the FDS are presented below in terms of the effect of FDS separation on cut size and grade-recovery response. Effect of FDS separation on cut size After rejecting any starting unclassified material in each test and on achieving study, state conditions at set parameters, product samples were collected and analysed individually. The results are summarized in Table 4,and feed and product size distributions shown in Figure 5. The results indicate that there was little variation in the density cut point, d 50 (~60µm size) for both cases. Table 4. Results of FDS test products physical characteristics analysis Solids (Weight %) Case-1 Case-2 Under Flow Over Flow Under Flow Over Flow Calculated % solids Calculated Feed ( % solids by mass) Calculated Feed rate (Kg/h) Cut Size d 75 c (µm) Cut Size d 50 c (µm) Cut Size d 25 c (µm) Imperfection (I)* XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

8 MURTHY AND BASAVARAJ Figure 5. Size analysis of feed and products from tests with FDS This can be seen from ascertaining the partition curves. For that reason, the Tromp curve is an effective tool to evaluate the separator performance which is a chart showing the probability of a given size of particle in the separation feed that will go to the rejects. Sharpness in classification efficiency, is generally evaluated by looking at the central section of a partition or tromp curve, the closure to vertical the slope, the higher is the efficiency (Wills and Napier Munn, 2006). Figure 6 illustrates the classification partition curve for the corrected values of the two case conditions that were tested. It is evident from the partition curves, that at the present, operating parameters, the FDS shows highly efficient in treating this complex low grade iron ore fines. Figure 6. FDS partition curves (corrected) for the two cases tested Alternatively, the performance of separating equipment can be evaluated using imperfection (I) values, which are calculated by using the formula, I = (d 75 -d 25 ) / 2d 50, where d x is the cut size and x is the % of mass recovered to the under flow for the values 75 and 25. For the value of 50, it is the mass recovery either to the under flow or to XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

9 ASSESSING THE PERFORMANCE OF A FLOATEX DENSITY SEPARATOR FOR THE RECOVERY OF IRON FROM LOW-GRADE AUSTRALIAN IRON ORE FINES A CASE STUDY the overflow. Besides, the performance of a separator is given by imperfection values, wherein, if I<0.2 -excellent separator, 0.2<I<0.3- Good Separator, 0.3<I<0.4- Medium Separator, 0.4<I<0.6- Poor Separator and if I>0.6- bad separator. Therefore, the lower is the I-value better is the classification efficiency. It is evident that, from the low experimental values of imperfection obtained (018 to 0.20), the FDS performance with respect to classification is efficient for the two cases tested. In addition, while preserving teetering/fluidisation condition in the bed, and operating with variations in the feed rates and bed levels, there was a little effect of these operating variables on separation efficiency. As a result, it was clearly seen, that FDS was ideal beneficiation equipment which absorbs fluctuations in feed rates and operating conditions while separating efficiently. Effect of FDS separation on product grade and recovery From the experimental results presented at Table 5, it is seen that, it is possible with the FDS to obtain a constant product grade of around 57.0% Fe (CaFe of about 63.0%) by rejecting deleterious Gangue minerals while recovering around 67.0% of the feed weight. Furthermore, this grade is achieved at >77% iron recovery and rejection of >75% of silica, and >66% of the alumina. Product Weight % Under Flow (Case-1) Under Flow (Case-2) Table 5. Grade and recovery for FDS under flow products Assay Percent Distribution Percent Fe SiO 2 Al 2 O 3 LOI* Ca Fe+ Fe SiO 2 Al 2 O Feed Chemistry of FDS under flow products are furtherly confirming that the variations in the feed rates, adjusting bed levels while keeping teetering/fluidisation conditions in the FDS separation system have shown less significant effect on the product chemistry. Thus, this type of feature may be attributed as an encouraging important factor, for plant operations with fluctuating feed size and/or grade characteristics from variations with run-of-mine ore. Moreover, as described above, this is achieved without affecting the product specifications while allowing sharp particle classifications by size and mass recovery On other hand, in both the cases tested, the calculated underflow pulp density was found to be at around 60% solids by weight (refer Table 4). Thus, indicating fluctuations in feed rates, bed levels and bed pressure had little effect on the underflow pulp density. As a result, it is apparent, that with its easy process controls, the FDS can absorb fluctuations in feed rates while delivering consistent dewatered thickened pulp to the under flow. Overall, assessment of FDS performance for treating complex lower grade iron ores has shown promising results in achieving good iron recovery and rejecting substantial quantities of deleterious minerals in a single stage operation. CONCLUSIONS In the present study, assessment of FDS in the treatment of low grade iron ore fines, was made with particular reference to rejection of silica and alumina bearing Gangue. Two sets of operating conditions were tested, and the following conclusions were drawn. The FDS was found to be effective in classifying near dense material and upgrading the complex leangrade iron ore type fines used as feed material. A recovery greater than 77% of iron having a grade around 63% calcined iron is possible with 48% iron content. For both test cases, the FDS was found to be easy to operate and control and the feed fluctuations in respect of variations in feed rates and bed pressures were absorbed by the FDS while delivering a consistent product in terms of size, grade and pulp density. XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER

10 MURTHY AND BASAVARAJ In this work, sharp partition curves were observed with low imperfection values ( ). The results indicate that the FDS can potentially be operated efficiently as a single stage separating system. ACKNOWLEDGEMENTS This work was carried out as a part of internally funded beneficiation studies at CSIRO. The financial support and encouragement of the CSIRO Process Science and Engineering Division in setting up the beneficiation capability is gratefully acknowledged. The authors also wish to thank the staff of High Temperature Processing Group at QCAT for their support during testing. The authors also acknowledge the input of CSIRO colleague Dr. SarathHappuguda for mineralogical and probe analysis. REFERENCES Asif, M, The complete segregation model for liquid fluidized bed: formulation and related issues, Powder Technol. 140, pp Barrios, G F, Increasing the capacity of the grinding circuits without installing more mills, in The Fourth Southern African Conference on Base Metals, ppp (The South African Institute of Mining and Metallurgy: South Africa). Clout, J M F, Iron formation-hosted iron ores in the Hamersley Province of Western Australia, Applied Earth Science (Trans. Inst.Min. Metall.B), Vol 115, No 4, pp Galvin, K.P, Pratten, S.J, Nguyen Tran Lam, G,1999a. A generalized empirical description for particle slip velocities in liquid fluidized beds, in Chem. Eng. Sci. 54, pp Galvin, K.P, Pratten, S.J, Nicol, S.K, 1999b. Dense medium separation using a teetered bed separator, Miner. Eng. 12 (9), pp Morris, R C, A Textural and Mineralogical Study of the Relationship of Iron Ore to Banded Iron-Formation in the Hamersley Iron Province of Western Australia, Economic Geology, Vol. 75, pp Murthy, N and Karadkal, B, Alumina Reduction Challenges in the Beneficiation of Low-Grade Haematite Iron Ores, Iron Ore Conference 2011, July 11-13, Perth Western, Australia, AusIMM publication series No 6/2011,pp Sarkar, B, Das, A, Rai, S.K, Chattoraj, U.S, Bhattacharya, N.K, Bhattacharya, K.K, Optimization of teetered bed separator for alumina removal form iron ore fines Proc.,Workshop on Iron Ore Beneficiation, June 16 17, Jamshedpur, India, pp Sarkar, B, Das, A, Mehrotra, S.P, 2008a. Study of separation features in floatex density separator for cleaning fine coal, Int. J. Mineral.Proc, 86 (1 4), pp Sarkar, B, Das, A, Roy, S, Rai, S.K, 2008b. Characterization of and alumina removal from an iron ore fines of Indian origin using teetered bed separator. Miner.Proc. Ext. Met. (Trans IMMC) 117 (1), ppc48 c55. Taylor, D, Dalstra, H J, Harding, A E, Broadbent, G C and Barley, M E, Genesis of High-Grade Haematite Ore bodies of the Hamersley Province, Western Australia, Economic Geology, Vol. 96, pp Tompkins, L A and Cowan, D R, Opaque mineralogy and magnetic properties of selected banded ironformations, Hamersley Basin, Western Australia,Australian Journal of Earth Sciences, 48, pp Wills, B A and Napier-Munn, T, Wills Mineral Processing Technology: An Introduction to the Practical Aspects of Ore Treatment and Mineral Recovery, 7th Edition (Elsevier: Australia). XXVI INTERNATIONAL MINERAL PROCESSING CONGRESS(IMPC) 2012 PROCEEDINGS / NEW DELHI, INDIA / SEPTEMBER