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The burden material in a blast furnace is essentially a collection of particles having wide range of size and shape. It is discharged from the hopper and distributed on the stock level. The mass distribution of the falling stream determines the shape of the stock profile. The stock profile dictates the radial variation of ore/coke ratio, size segregation, gas distribution and burden descent, which in turn influence the formation and shape of the cohesive zone. Knowledge of the stock profile is therefore essential for understanding these phenomena. The complex nature of the flow has made a first-principle prediction of the mass distribution in the falling stream extremely difficult. Kondoh et al. 1) have reported mass fraction distribution in the falling stream at different elevation but the complete description as a function of chute angle is not reported. The present work attempts to predict the mass fraction distribution in the falling stream for three burden materials, viz. iron ore, coke and sinter. ExperimentationThe experiments were conducted using actual bell less top charging equipment of the furnace in a trial rig. Figure 1 shows a schematic diagram of the experimental setup. The rig was comprised of the complete material charging system including receiving hopper, common hopper, upper seal valve, lower seal valve, flow control gate and rotation chute. A brick-walled cylindrical tank of 5 m diameter and 1.5 m height was built for simulating the furnace throat. A small section of the cylindrical wall was kept open for removal of the charged materials. Proper electrical and mechanical arrangements were made for the rotational motion of the distributing chute. Tilting angle of the chute was changed manually and the chute was set to rotate at a constant speed. To feed the material in the receiving hopper, a special charging hopper of volume 1.43 m 3 was fabricated with a discharge gate at the bottom.For the purpose of collecting the materials from the falling particle stream, a semi-cylindrical pipe was inserted along the throat diameter at 1.6 m below the chute tip (design stock level). The pipe was divided into 25 compartments of 20 cm width each. In the experiment, rotating chute distributed the material along the peripheral direction and completed full rings. When the falling stream crossed the inserted pipe, material was collected in the different compartments, as shown in Fig. 2. For each full ring rotation of the chute, material was collected in two different locations, one on either side of the throat centre-line. Materials from individual compartments were weighed and mass fraction distribution was calculated. Results and DiscussionThe striking position of the falling stream of sinter for different chute inclination angle is shown in Fig. 3. The stream moves toward furnace wall with the increase in chute angle. In the figure, the filled points are the striking positions of the outer stream and the void points are the striking points of the inner stream. The stream width, defined as the distance...

Concentrations of total dissolved cadmium (Cd) and activity of its free ions in soil solution are suggested to be influenced by soil pH, organic matter (OM) content, cation exchange capacity (CEC), and clay mineralogy. We investigated the sorption of Cd by taking 25-, 50-, and 100-µM Cd solutions in five noncontaminated soils of West Bengal, India, having differing chemical properties with batch sorption experiments. The charge characteristics and point of zero salt effect (PZSE) of all experimental soils were calculated by the potentiometric titration method measuring the adsorption of H+ and OH– on amphoteric surfaces in solutions of varying ionic strength (I). Sorption of Cd was more pronounced at pH levels greater than PZSE for all experimental soils. The CEC, OM content, clay mineralogy, and specific surface area (SSA) also had a great influence on the sorption of Cd from soil solution to soils. The relationships of Cd with those parameters were found to be consistent and the results concluded that Cd sorption in soils is strongly affected by the soil characteristics.

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Aim:A pilot study was carried out to find out the seroprevalence of Porcine circovirus 2 (PCV2), classical swine fever virus (CSFV), and Porcine respiratory and reproductive syndrome virus (PRRS) in pig population of Meghalaya.Materials and Methods:Serum samples were collected from piglets of 40–45 days age group, growers, and sows reared under organized and unorganized management in 11 districts of Meghalaya situated in the Khasi, Jaintia, and Garo hills divisions in the time period of 2014-2016 from apparently healthy and suspected pigs. Seroprevalence of PCV2, CSFV, and PRRS specific antibodies was detected by enzyme-linked immunosorbent assay (ELISA).Results:A total of 1899 serum samples were collected and screened using antibody ELISA kits specific for PCV2, CSFV, and PRRS. The highest antibody prevalence during the selected time periods was detected for PCV2 (80.8% in 2014, 79.1% in 2015, and 96.2% in 2016) followed by CSFV (76.4% in 2014, 66.09% in 2015, and 25.5% in 2016) and PRRS (2.8% in 2014, 2.7% in 2015, and 3.62% in 2016). The result indicates high seroprevalence for PCV2, which can be considered as an inducement factor due to the immunosuppressive nature of the virus, for animals being susceptible to other pathogens in farms where airborne transmission of PCV2 and postweaning multisystemic wasting syndrome among animals reared in close pens can be a major possibility.Conclusions:The data from this study indicates ubiquitous prevalence of PCV2 antibodies in the farm animals along with the endemic presence of swine fever and emergence of PRRS in an organized farm. There are few reports regarding PCV2 infections/outbreaks in pigs associated with reproductive failure from northern and southern part of India, but till date, there are no reports regarding concomitant infection of CSFV and PCV2 from India. Considerable high seropositivity of PCV2 indicates the need for high impact hygiene practice in farms, routine seromonitoring and implementation the vaccination program. To the author’s best knowledge, this is the first documented report on the seroprevalence of PCV2, CSFV, and PRRS from pig population of Meghalaya.