Faculty Publications

Now showing 1 - 4 of 4

Effect of media characteristics on performance of upflow aerobic biofilters
(2008) Srinikethan, G.; Shrihari, S.; Pradeepan, V.S.
Laboratory studies were conducted to assess the influence of media related factors such as porosity, pore size, particle size and specific surface area on the performance of upflow aerobic biofilters (ABFs). Three simple models of 8 litre capacity upflow submerged ABFs packed with support media of size 40 mm, 20 mm and 10 mm respectively were installed. The hydraulic retention time (HRT) was maintained as 12 hours. The study was carried out for a period of 90 days. The reactor performance indicated that the aerobic biofilter (ABF-3), associated with media of lowest porosity, pore size, particle size and highest specific surface area, demonstrating the highest BOD and COD removal efficiency of 93.32 % and 85.01 % respectively.
Optimum size of granite filter media for the maximum treatment of domestic sewage in upflow anaerobic biofilters
(2008) Srinikethan, G.; Shrihari, S.; Pradeepan, V.S.
Laboratory studies were conducted to assess the influence of media related factors such as particle size, porosity, pore size and specific surface area on performance of upflow anaerobic biofilters (AnBFs). Three simple models of 8 litres capacity upflow anaerobic biofilters (AnBFs) packed with support media granite of size 40 mm, 20 mm and 10 mm respectively were installed. The experimental anaerobic biofilters (AnBFs) were made of PVC tubes. The hydraulic retention time (HRT) was maintained as 12 hours. The study was carried out for a period of 90 days. The waste treatment performance indicates that the anaerobic biofilter (AnBF-2) packed with granite media of moderate particle size of 20mm demonstrated the highest BOD and COD removal 91.02 % and 82.01 % respectively. Copyright © Enviromedia.
Selection criteria for decorative dimension stones
(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Manjunatha, B.R.; Venkat Reddy, D.V.; Krishnakumar, K.N.; Balakrishna, K.; Manjunatha, H.V.; Gurumurthy, G.P.
Selection of decorative dimension stones suitable for exterior and interior decorations is one of the challenging tasks for geologists, architectural, structural and civil engineers. Therefore, understanding the knowledge of general properties of commercial grade rocks and their quality assessment are at most important before selecting stones for construction. In many instances, decorative dimension stones are usually preferred on the basis proximity. In such cases, the colour and textural characteristics may not only be suitable, but also weather out faster. In some instances, specific design may not suits the structure due to masking colour and other inherent defects. One of the secrets behind the success of commercial stone industry is the production of defect-free decorative dimension stone blocks. Generally, not all rocks available in the earth’s crust are suitable for architectural and civil engineering construction purposes. In this study, the main criteria for the selection of commercial grade decorative dimension rocks will be discussed along with their trade names. Sometimes, trade names of rocks confuse with generic names. Here, therefore, both names of rocks, particularly marketed in India are given to avoid confusion among geologists, engineers and business persons. In addition, non-destructive methods of testing the mechanical properties of rocks - such as ultrasonic pulse velocity and uniaxial compressive strength are discussed. These methods seem to substitute the conventional, hazardous and destructive method of testing of decorative dimension stones. ©2014 Cafet-Innova Technical Society. All rights reserved.
Experimental study on failure and fracturing attributes of granite after thermal treatments with different cooling conditions
(Elsevier B.V., 2022) Srinivasan, V.; Hasainar, H.; Singh, T.N.
Thermal damage is one of the fundamental mechanisms affecting the stability of rocks encountered in many deep geo-engineering ventures such as nuclear waste isolation, geothermal extraction etc. In the present study, the findings on influence of heating and subsequent cooling conditions on the fracturing and mechanical behaviour of an Indian granite are discussed. The granite samples from Jalore region of India were heated from room temperature to 600 °C followed by slow cooling and water quenching treatments. It was observed that rapid cooling through quenching had a greater impact on strength, elastic properties than slow cooling rate. Moreover, a drastic shift in terms of fracturing thresholds was witnessed, as a function of both temperature and sudden thermal shock experienced by rock at higher cooling rate. The simultaneous AE monitoring results suggested an early crack damage at higher thermal regimes. With help of microscopic observations, it was observed that inter-granular crack boundaries widened with increasing thermal damage experienced by minerals under both cooling conditions. However, the fracturing process was intense under rapid cooling treatment due to the invasion of water due to quenching which accelerated severe intra-crack growths, especially at higher thermal stress because of the rapid cooling rate than the slow cooling. The increased intensity of thermal cracks with temperatures and with variation in cooling rate was inferred as the primary reason for decay of rock characteristics. This was very well supplemented by decay in strength properties and changes in fracturing attributes of the tested granite as inferred from acoustic monitoring. © 2022

Faculty Publications

Browse

Filters

Settings

Sort By

Results per page

Search Results