Papers by Anjireddy Bhavanam
Gasification has great potential to make use of the biomass and wastes as a source for energy amo... more Gasification has great potential to make use of the biomass and wastes as a source for energy among various thermochemical conversion processes. The aim of this work is to study the suitability of yard waste for energy conversion using gasification process by Thermo gravimetric analysis. Yard waste (consisting of leaves, twigs and grass clippings) is collected from the National Institute of Technology Warangal. It is then dried and ground to a particle size of less than 250μm for thermo gravimetric study. Before going to thermo gravimetric analysis; the sample is analyzed to measure the main properties that affect thermal conversion. Moisture content present in the sample is determined by the oven drying method. Proximate is done according to standard ASTM test methods and ultimate analysis is conducted using elemental analyzer. Finally thermo gravimetric analyses is performed at various heating rates of 10, 30, and 50°Cmin−1 in nitrogen (inert) and air (oxidizing) atmospheres. The weight losses of yard waste in inert atmosphere occur in three stages and in air it occurs in four stages.
Fuel, Feb 1, 2021
Abstract In this study, the bamboo saw dust (BSD) was wet-torrefied (WT) to selectively remove he... more Abstract In this study, the bamboo saw dust (BSD) was wet-torrefied (WT) to selectively remove hemicellulose in the form of pentoses (xylose + arabinose) with 85% yield and to produce hydrochar (with the high energy density of 24 MJ/kg, which is similar to that of lignite). Further, the pyrolysis and co-pyrolysis behavior of hydrochar, LLDPE, and their blends were analyzed by thermogravimetric analysis in the temperature range of 30–800°C and under argon atmosphere. The blend with one part hydrochar and three parts LLDPE (TBP1:3) showed the highest positive synergism during co-pyrolysis at a 40 °C min−1 heating rate. The average apparent activation energies (as calculated using isoconversional methods) of co-pyrolysis of blended samples (TBP3:1, TBP1:1, and TBP1:3) were found to be 232, 261, 247 kJ mol−1, respectively. The Criado's master plot showed the reaction mechanism of co-pyrolysis to be multistep. For example, the blend TBP1:3 followed the trend of two-dimensional Avrami-Erofeyev model (A2) at lower conversions, diffusion-reaction model (D2) at high conversions and end with a first-order reaction.
Renewable Energy, Apr 1, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Lignocellulosic biomass (LCB) is formed with structural components of cellulose, hemicellulose an... more Lignocellulosic biomass (LCB) is formed with structural components of cellulose, hemicellulose and lignin. This chapter will discuss about the structure and chemical composition of the above three structural components. Various pre-treatment processes for fragmentation of LCB into separate components are also discussed. For optimal conversion of these components into viable chemicals various processes (Hydrolysis, oxidation, pyrolysis, hydrothermal liquefaction, etc.) are developed. These processes use various types of catalysts (homogenous and heterogeneous) for increasing the yield and selectivity of products. Cellulose and hemicellulose fractions are mostly used for production of ethanol. Lignin is obtained as a by-product in these processes. Lignin, which represents up to 30% of the lignocellulose biomass, is an unexploited treasure that contains such a large number of aromatic compounds. The potential of lignin is therefore quite high: besides cellulose and chitin, lignin is the most abundant polymer in nature. Selective depolymerization of LCB using various catalysts and pre-treatment methods produce a wide spectrum of aromatics and chemicals which are difficult to make via existing petrochemical routes.
International Journal of Chemical Engineering and Applications, 2011
Biomass Gasification is a chemical process that converts biomass into useful convenient gaseous f... more Biomass Gasification is a chemical process that converts biomass into useful convenient gaseous fuels or chemical feedstock. It has emerged as a promising technology to fulfill the increasing energy demands of the world as well as to reduce significantly the volume of biomass waste generated in developing societies. In this paper, various aspects of the research and development in biomass gasification in downdraft fixed bed reactors like advances in downdraft gasification systems, and the effect various parameters like equivalence ratio, operating temperature, moisture content, superficial velocity, gasifying agents, residence time on the composition of producer gas, yield and conversion are reviewed Index Terms-Gasification, biomass, downdraft gasifier (DDG), equivalence ratio(ER), producer gas.
Environmental science and engineering, 2022
Bioresource Technology, Feb 1, 2015
The pyrolysis characteristics of municipal solid waste, agricultural residues such as ground nut ... more The pyrolysis characteristics of municipal solid waste, agricultural residues such as ground nut shell, cotton husk and their blends are investigated using non-isothermal thermogravimetric analysis (TGA) with in a temperature range of 30-900 °C at different heating rates of 10 °C, 30 °C and 50 °C/min in inert atmosphere. From the thermograms obtained from TGA, it is observed that the maximum rate of degradation occurred in the second stage of the pyrolysis process for all the solid wastes. The distributed activation energy model (DAEM) is used to study the pyrolysis kinetics of the solid wastes. The kinetic parameters E (activation energy), k0 (frequency factor) are calculated from this model. It is found that the range of activation energies for agricultural residues are lower than the municipal solid waste. The activation energies for the municipal solid waste pyrolysis process drastically decreased with addition of agricultural residues. The proposed DAEM is successfully validated with TGA experimental data.
Fermentation, Dec 3, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Polymer Composites, Feb 15, 2017
The solid particle erosion behavior of Arhar particulate epoxy composites with 5, 10, and 15 wt% ... more The solid particle erosion behavior of Arhar particulate epoxy composites with 5, 10, and 15 wt% particulate content has been characterized. The Arhar particulate epoxy composites have been fabricated using hand lay-up technique, and samples have been exposed to different environmental conditions, such as dry, saline, mineral water, kerosene, and subzero, before erosion test. The effect of different environments on erosion wear rate is investigated for all the composites. The rate of erosion at which Arhar particulate epoxy composites undergo when subjected to various impingement angles (30, 45, 60, and 908) and at particle speeds (v 5 86, 101, and 119 m/s) using air jet erosion test rig has been evaluated. Erosion behavior of Arhar particulate composites is found to be less when compared with neat epoxy material. Normal samples showed semibrittle erosive behavior. Erosive wear rate is more in samples with 15 wt% particulate content. Erosion wear is higher in samples immersed in saline water. Erosive wear behavior samples immersed in saline water, mineral water, and kerosene, which is found to be semibrittle.
This study presents a mathematical model to predict synthesis gas (CO+H 2) composition from selec... more This study presents a mathematical model to predict synthesis gas (CO+H 2) composition from selected solid wastes (municipal waste, animal waste and agricultural waste) in a downdraft fixed bed reactor. This model assumes chemical and thermodynamic equilibrium with products inside the reactor. Effect of temperature in gasification zone, equivalence ratio and moisture content of biomass on gas composition was investigated. Model helps to know the behaviour of different biomass types and is a useful tool for predicting operating parameters of downdraft gasifiers with this biomass.
Journal of Material Cycles and Waste Management, Dec 27, 2017
The continuous increase in generation of solid wastes and gradual declining of fossil fuels neces... more The continuous increase in generation of solid wastes and gradual declining of fossil fuels necessities the development of sustainable conversion technologies. Recent studies have shown that the addition of biomass with hydrogen-rich co-reactants (plastics) altogether enhances the quality of bio-fuels using pyrolysis process. It was observed that red mud (which is produced as by-product in Bayer process) was used as a catalyst in few conversion process. In this study, pyrolysis of biomass (Pterospermum acerifolium) and waste plastic mixture with activated red-mud catalyst was investigated using thermogravimetric analysis. The kinetic parameters (activation energy and pre-exponential factor) of this process were determined using distributed activation energy model (DAEM). The DAEM was effectively applied to decide the activation energy (E) and pre-exponential factor (A) for each sample at various conversions during the catalytic co-pyrolysis. The biomass, plastic, biomass-plastic, and biomass-plastic-catalyst exhibited activation energies in the ranges of 78-268, 172-218, 67-307, and 202-292 kJ/mol, respectively.
Biomass Conversion and Biorefinery
Kraft pulping process is the foremost common pretreatment method utilized in pulp and paper busin... more Kraft pulping process is the foremost common pretreatment method utilized in pulp and paper businesses to break down the lignocellulosic linkages to urge cellulose and lignin separated. Due to higher degree of recuperation of the reagents utilized within the process of pulp production having higher cellulosic virtue, this technique rules over others since many decades. A factorial experiment may have star points and centre points added, offering three or five levels for each component. This is known as a central composite design, and it is utilised in response surface modelling. There are a few components to be considered in kraft pulping method which are temperature, retention time, % alkalinity, % sulfidity, and liquor to biomass stacking. The use of Na2S stands for a source of HS−, but too for an extra source of NaOH agreeing to the response included in this prepare. In spite of the fact that we have not taken those two components into thought, they can moreover be utilized in future inquire about. Thus, here, we utilized central composite plan to optimize our components. By taking temperature extend of 140–175 °C, time 20–80 min, and % alkalinity 10–20%, we have gotten diverse reactions of greatest bright absorbance wavelength and concentration information of black liquors.
Journal of Energy Chemistry
Fermentation
Corncobs of four different corn varieties were physically segregated into two different anatomica... more Corncobs of four different corn varieties were physically segregated into two different anatomical portions, namely the corncob outer (CO) and corncob pith (CP). The biomass composition analysis of both the CO and CP was performed by four different methods. The CP showed a higher carbohydrate and lower lignin content (83.32% and 13.58%, respectively) compared with the CO (79.93% and 17.12%, respectively) in all of the methods. The syringyl/guaiacyl (S/G) ratio was observed to be higher in the CP (1.34) than in the CO (1.28). The comprehensive physical characterization of both samples substantiated the lower crystallinity and lower thermal stability that was observed in the CP compared to the CO. These properties make the CP more susceptible to glycanases, as evident from the enzymatic saccharification of CP carried out with a commercial cellulase and xylanase in this work. The yields obtained were 70.57% and 88.70% of the respective theoretical yields and were found to be equal to t...
Environmental Science and Engineering
The use of general descriptive names, registered names, trademarks, service marks, etc. in this p... more The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.
Bioresource Technology Reports
Handbook of Biomass Valorization for Industrial Applications, 2022
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Papers by Anjireddy Bhavanam