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Subject: search.filters.subject.Dewatering

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Now showing 1 - 7 of 7
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    Enhancing the Dewatering Ability of Sludge by Locally Available Biomass
    (Springer Nature, 2023) Chopade, G.; Devatha, C.P.
    In this study, the effect of modified coconut shell biochar is analyzed for its efficacy achievable in sludge dewatering properties. Initially the coconut shell biochar is modified at different molar concentrations of FeCl3, i.e., 1, 2, and up to 5 mol/L, and it is analyzed with different dosages at 0.1, 0.2, and up to 0.4 (g/g of dry solids (DS)) for the improvement in capillary suction time (CST) (s), moisture content reduction (%), filterability (min), and settleability (SV30%) of the sludge. It is found that there is significant decrease in each of these parameters. The optimization study is carried out to optimize the process of sludge conditioning, considering independent regression parameters as dosage (g/g of DS), molarity (M), mixing time (min), and response taken as moisture content (%), the optimum values for the dosage, molarity, mixing time is found to be 0.4 (g/g of DS), 2.5 M and 24.72 min, respectively, with optimized moisture content value of 78% was achieved. Hence, the modified coconut shell biochar can be used as a potential candidate to increase the dewatering ability of the sludge. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.
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    An empirical model for the estimation of moisture ratio during microwave drying of plaster of Paris
    (2008) Ganesapillai, M.G.; Iyyaswami, I.; Murugesan, T.
    The drying characteristics of plaster of Paris (POP) under microwave irradiation were studied for different shapes of materials through various drying parameters like microwave power, initial moisture content, and drying time. An empirical model for the estimation of moisture ratio was developed using the drying kinetic data of POP. Further, the experimental data on moisture ratio of POP for different operating conditions were fitted with the nine basic drying model equations. Based on the observations, the constants and coefficients of the literature models were rewritten in the form of Arrhenius and logarithmic expressions considering microwave power as input variable. Fifty-eight new model expressions were derived by changing the constants and coefficients and tested using the present experimental data. From the analysis of RMSE, ?2, and EF parameters for the derived models, a suitable empirical model (Model No. 55, RMSE = 0.0874; ?2 = 0.0020; EF = 0.9999) was established to represent the present experimental data on microwave drying of POP.
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    Characterization and process optimization of microwave drying of plaster of Paris
    (2008) Ganesapillai, M.G.; Iyyaswami, I.; Murugesan, T.
    The changes in the characteristics of plaster of Paris (pop) during drying operation under microwave irradiation conditions, namely surface morphology, effective moisture diffusivity, and absorption of microwave, were studied. The drying characteristics and kinetics of the process during microwave drying of plaster were studied for rectangular-faced cuboids (80 × 70 × 15, L × B × H in mm) through various drying parameters like microwave power input, initial moisture content, and drying time. Further, the experimental data on moisture ratio of plaster for different operating conditions were obtained and the optimization of the microwave drying process parameters was performed with response surface methodology (RSM) by considering all the above-said independent variables. Based on the RSM analysis, the optimum values of the process variables were obtained as: initial moisture content (A) 60%; microwave power input (B) 180 W; and drying time (C) 480 S.
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    Moisture diffusivity and energy consumption during microwave drying of plaster of Paris
    (2010) Ganesapillai, M.G.; Iyyaswami, I.; Miranda, L.R.; Murugesan, T.
    The drying characteristics of plaster of paris (POP) under microwave conditions at different microwave power input, initial moisture content, sample thickness and drying time were studied. Further the experimental data on moisture ratio of POP for different operating conditions were obtained and calculations were made using nine basic drying model equations. The appropriate model with modified constants and coefficients to represent the drying kinetics of POP was found through the analysis of the statistical analysis. The effective moisture diffusivity of the drying process was also computed for different experimental conditions and a relationship between the drying rate constant and the effective moisture diffusivity was obtained. The energy consumption for microwave drying of plaster of paris at different experimental conditions were also computed. © 2010 The Berkeley Electronic Press. All rights reserved.
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    Growth and thermal studies on pure ADP, KDP and mixed K 1-x(NH4)xH2PO4 crystals
    (2010) Shenoy, P.; Bangera, K.V.; Shivakumar, G.K.
    The investigations on the formation of mixed crystals of ammonium dihydrogen orthophosphate (ADP) and potassium dihydrogen orthophosphate (KDP) i.e. potassium ammonium dihydrogen phosphate, K1-x(NH 4)xH2PO4 have been presented in this paper. Pure and mixed crystals of ADP and KDP have been grown by slow evaporation technique from the supersaturated solution at an ambient temperature 26±1 °C for ammonium concentration x in the range 0.0 ? × ? 1.0 in the case of mixed crystals. Crystal compositions were determined by flame atomic absorption spectroscopy and chemical analysis. The results of the X-ray analysis of the grown crystals are also reported. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study the kinetic process of dehydration and the high temperature phase behaviour. DTA showed the distinct thermal events attributed to dehydration of ADP, KDP and K1-x(NH4)xH2PO4. The results of thermal analysis and chemical analysis are consistent with each other. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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    Dewatering performance of sludge using coconut shell biochar modified with ferric chloride (Sludge dewatering using bio-waste)
    (Springer Science and Business Media Deutschland GmbH, 2022) Rashmi, H.R.; Devatha, C.P.
    Coconut shell is a bio-waste, and its availability is high to waste in the coastal region of Karnataka, India. The present study focused on using coconut shell biochar modified with ferric chloride to enhance the sludge dewaterability, and it is evaluated experimentally (Capillary suction time, moisture content, settleability, zeta potential, heavy metals, and phosphate). Further, scanning electron microscopy, Fourier transformation infrared spectroscopy, and X-ray diffraction characterization were carried out to identify the structure's change. A significant reduction in capillary suction time (56 s) and the moisture content (96.5%) of the dewatered sludge cake was obtained. Sludge dewatering using coconut shell biochar modified with ferric chloride was optimized by a Box Behnken method with three main factors including dosage, rapid mixing time, and slow mixing time. Optimum capillary suction time (55.6 s) was achieved at coconut shell biochar modified with ferric chloride dosage (41% dry solids), rapid mixing time (10 min), and slow mixing time (19 min). The significant structural change in sludge particles was confirmed through characterization studies. During the dewatering process, the removal of heavy metal (cadmium, chromium, lead, and nickel) and phosphate (50.6%) was evident. Hence attempt of coconut shell biochar modified with ferric chloride as a skeleton material is an economical and promising option for sludge dewatering. © 2021, Islamic Azad University (IAU).
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    Experimental investigation on sludge conditioning and dewatering using an agricultural biomass coupled with resource recovery
    (Academic Press, 2024) Chopade, G.; Devatha, C.P.
    In this study, the effect of modified areca husk fibre biochar (MAFB-AlCl3) on dairy sludge conditioning and dewatering along with raw and modified coconut shell biochar (MCSB-FeCl3) was investigated. Further, MgO impregnated biochars of areca husk fibre and coconut shells was carried out to evaluate the performance on phosphate recovery from the diary sludge. The enhancement in sludge dewatering with MAFB-AlCl3 were evaluated experimentally and significant reduction of capillary suction time (CST) (51.6 %), moisture content (18%), zeta potential (1.3 mV) and increased settleability (32.7%) were observed. The sludge conditioning parameters namely dosage (% of dry solids (DS)), rapid mixing time (RMT), slow mixing time (SMT) were optimized by response surface methodology for the modified biochars. Optimum CST (31.51 s) was obtained at dosage (50 % of DS), RMT (9.89 min) and SMT (17.23 min). Results of batch study for phosphate recovery by MgO impregnated biochars (MgB) was found to be 96.6 % and 100 % by MgB of areca husk fibre (MgAFB) and coconut shells (MgCSB) respectively. The morphological characteristics and elemental distribution using field emission scanning electron microscopy (FE-SEM) & energy dispersive X-ray spectroscopy (EDS) reveals the structural change in the sludge particles for the modified biochars as well as for sludge. Hence MAFB-AlCl3, MgAFB and MgCSB is proved to be suitable and an effective candidate for sludge conditioning and dewatering coupled with phosphate recovery in handling the diary sludge. © 2024 Elsevier Ltd