Prashant V. Thorat

Bio: Prashant V. Thorat is an academic researcher from Sant Gadge Baba Amravati University. The author has contributed to research in topics: Membrane distillation & Castor oil. The author has an hindex of 4, co-authored 8 publications receiving 54 citations. Previous affiliations of Prashant V. Thorat include Yahoo!.

Performance evaluation of vacuum membrane distillation for desalination by using a flat sheet membrane

Abstract: Vacuum membrane distillation (VMD) process received a great deal of attention by many investigators because of its promising applications in several separation areas. It is a rising technology for seawater or brine desalination process. The process simply consists of a flat sheet hydrophobic microporous PTFE membrane and diaphragm vacuum pump without a condenser for the water recovery or trap. In this work, VMD performance was investigated for aqueous NaCl solution. In order to enhance the performance of the VMD process in desalination, that is, to get more flux, it is necessary to study the effect of operating parameters on the yield of distillate water. The influence of operational parameters such as feed flow rate, feed temperature, feed salt concentration and permeate pressure on the membrane distillation (MD) permeation flux have been investigated. The VMD performance showed that this device could reach a desalting degree of 99.99% which was not affected by feed concentration. The membrane distillati...

Utilization of polymer waste for modification of bitumen in road construction

Abstract: Generation of polymer waste is increasing day by day and necessity to dispose this waste in proper way is arising. This waste is disposed by using different methods such as incineration, land-filling which affects the environment; but by adding polymer into roads is the eco-friendly process. The addition of polymer into dry bitumen improves the service properties of bitumen. If we use the polyolefins waste with or without crumb rubber upto certain percentage of bitumen then the properties of modified bitumen will be increased. The use of this innovative technology (polymer loading into bitumen) not only strengthen the road construction but also increases the road life as well as will help to improve the environment and also creating a source of income. By utilization of such polymer waste would be a boon for India’s hot and extremely humid climate, where temperature frequently crosses 50 0 C and torrential rains create havoc, leaving most of roads with big potholes. There are two types of techniques can be used for disposal of polymer waste in road construction. Dry process is suitable because by this process 15-20 % of plastic waste addition by weight % with respective to aggregate. But considering the limitations of this process that it is applicable to plastic waste only and hence our aim of disposing the total polymer waste for eco-friendly environment cannot be completely achieved. Wet process though it requires strong mechanical stirrer and continuous rotation, batch type production and separate chamber. If processing parameters such as heat losses, temperatures etc. are properly controlled there is reduction in the residence time which minimizes production time and thus improves productivity, hence this process is economically feasible and limitations of dry process can be overcome. As far as type of polymer waste is concerned, wet process is suitable for any type of polymeric waste (rubbery or plastic) or any size and form (either strand or powder). By the actual experimentation, we obtained optimum results for polymer waste at different composition. Hence, from the results, polyolefin waste can be loaded upto 6% HDPE, LDPE upto 6%, PP upto 4% crumb rubber upto 4% and mixture of crumb rubber and HDPE waste upto 8% (4% + 4%) in road construction. Under the similar conditions most of the bitumen roads are performing well at all.

Pesticide Wastewater Pollution and Treatment Methods: Review

Abstract: The persistent pesticides occur in the water cause potential adverse effects on the environment and public health. Due to high use of pesticides in the agricultural developed area/ country and public health sector, hence is posing a challenge to remove the pesticides from wastewater. In this paper a review of pesticides in wastewater in India is presented. The current scenario of pesticide wastewater and its various treatment methods are cited. Each method has its own advantages and limitations in terms of removing the pollutants, efficiency and economical effectiveness. Currently, membrane distillation is an effective technique can be used to treat pesticide wastewater.

A Review on Synthesis and Characterization of Castor Oil Based Polyurethane Adhesive

Abstract: This review paper gives the idea about use of raw materials from renewable sources to synthesis polyurethane adhesive which is important from social, environmental and economic view as compared to those produced form petrochemical sources. Polyurethanes based on castor oil were synthesized with polyols and toluene diisocyanate, and amine as a catalyst. The degree of swelling, mechanical properties, and polymerization kinetics was greatly affected by the diisocyanate nature. The aim of this review paper is to give a fundamental description of castor oil and various application of polyurethane adhesive like wood, metal, etc

Plastic Optical Fiber

Abstract: Polymer optical fibre is an optical fiber which is made out of plastic. Traditionally PMMA (acrylic) is the core material, and fluorinated polymers are the cladding material. Since the late 1990s however, much higher- performance POF based on perfluorinated polymers (mainly polyperfluorobutenylvinylether) has begun to appear in the marketplace.POF has been called the "consumer" optical fiber because the fiber and associated optical links, connectors, and installation are all inexpensive. polymer fibers are commonly used for much higher-speed applications such as data center wiring and building LAN wiring. In relation to the future request of high-speed home networking, there has been an increasing interest in POF as a possible option for next-generation Gigabit/s links inside the house. Although the actual cost of glass fibers are lower than plastic fiber, their installed cost is much higher due to the special handling and installation techniques required.

Reverse Osmosis and Membrane Distillation for Desalination of Groundwater: A Review

Abstract: In recent years, the increasing threat to groundwater quality due to human activities has become a matter of great concern. The groundwater quality problems present today are caused by contamination and by overexploitation, or by combination of both, which are faced by many Indian states. Today, reverse osmosis (RO) membranes are the leading technology for desalination of groundwater because of their strong separation capabilities and exhibiting a great potential for treatment of waters worldwide. However, the RO process had some problems due to the formation of polarization films because high pressure operation and by-products which may generate bacteria and fouling. Also, high energy consumption and brine disposal problem is faced in RO process due to the limited recovery of water. These problems may be overcome by other membrane thermal process such as a membrane distillation (MD). This paper addresses the outline of RO and MD process for desalination. RO has developed over the past 40 years and MD is an emerging technology for brackish water desalination and yet is not fully implemented in industry. The MD is the better alternative to RO for desalination theoretically found in the literature.

Preparation and properties of PTFE hollow fiber membranes for desalination through vacuum membrane distillation

Abstract: Polytetrafluoroethylene (PTFE) hydrophobic hollow fiber membranes were prepared through a cold pressing method including paste extrusion, stretching and sintering. The effect of stretching ratio on the characteristics of PTFE hollow fiber membranes was investigated. The morphological property of the PTFE hollow fiber membrane was studied in terms of field emission scanning electron microscopy (FESEM). It was observed that the PTFE hollow fiber membranes with four stretching ratios (120%, 160%, 180% and 220%) showed the microstructures of nodes interconnected by fibrils. Increasing stretching ratio was positive for pore size and porosity but negative for water entry pressure and mechanical property. The result of water contact angle measurement showed that the prepared PTFE hollow fiber membrane was a superior hydrophobic membrane material. Finally, the PTFE hollow fiber membranes were tested for their performances in the process of desalination through the vacuum membrane distillation (VMD). An increase in stretching ratio significantly improved the permeation flux. The salt rejections achieved 99.9% for all the PTFE hollow fiber membranes with four stretching ratios in this study, indicating the prepared PTFE hollow fiber membranes exhibited satisfying salt rejection performances.

Experimental and theoretical analyses of temperature polarization effect in vacuum membrane distillation

Abstract: This paper discusses the effect of temperature polarization in Vacuum Membrane Distillation (VMD). The main motivation for using VMD in this work is that this module configuration is much simpler and more suitable for this kind of investigation than the other MD configurations such as Direct Contact Membrane Distillation (DCMD). The coupling between heat and mass transfer mechanisms at the feed-membrane interface is presented from a theoretical point of view. In addition, a new simple graphical method and a mathematical model for determining VMD flux are presented. The two methods used in evaluating the extent of temperature polarization effect on water vapor flux (flux sensitivity factors and temperature polarization coefficient (TPC)) are also analyzed and compared. The effect of integrating a heat recovery system in a large scale module on the TPC coefficient has also been studied and presented in this paper.

Direct contact membrane distillation for seawater desalination

Abstract: Membrane distillation (MD) is a non-isothermal membrane separation process. It is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions, with vapor passing through a hydrophobic microporous membrane when a temperature difference is established across it. In this work, three commercially available hydrophobic microporous membranes were used for seawater desalination via direct contact MD. The effects of pertinent operating parameters on the permeation flux have been studied. A plate and frame module was used for seawater desalination. Long-term performance evaluation was carried out to evaluate the process as a stand-alone desalination alternative. The results indicated that polytetrafluoroethylene membrane had the best performance when a hot feed temperature of 80°C with 800 ml/min flow rate was used. At optimum condition a 99.99% salt rejection was achieved.

Challenges of plastic waste generation and management in sub-Saharan Africa: A review

Abstract: Recently, the issues of land-based plastics and their associated challenges in the marine world have been widely publicised in the media and scientific literature. Thus far, despite these communications, there have been few reports that have focused on the issues that acute plastic waste generation and its poor management pose to human health and the global environment. Also, articles on ways to mitigate these issues particularly in sub-Saharan Africa have not been documented. Indeed, there is significant scope for improvements in plastic waste management in developing countries, which offer a wide range of economic and environmental benefits. Plastic waste generation in sub-Saharan Africa is dependent on many factors like urbanization, etc. Currently, the population of sub-Saharan Africa is around 1 billion as of the year 2019, the amount of generated waste is 180 million tonnes at the rate of 0.5% per capita per day, the amount that is openly dumped is 70% and the plastic waste generated annually is 17 million tonnes. Therefore, this study aims to provide an overview of the plastic lifecycle and problems associated with plastic waste management in sub-Saharan Africa, including current practices, public participation and opinion, and government regulations. In addition, this highlight aims to outline the impact of plastic waste proliferation on man and the environment; and the economic and environmental benefits of proper plastic waste management. Critical discussion of current processes and the suitability of potential solutions provide the basis for proposition on mitigation measures to avert the negative impact of plastic waste.