pedaling, the valve to the vacuum pump can be shut off, and the zeolite Keywords: Pedal Powered Refrigerator, Zeolite, Vacuum Refrigerator, Methanol. Pedal Powered Refrigeration system based on Zeolite Adsorption Phenomena. Pedel Powered Zeolite (Vacuum) Refrigerator - Download as Powerpoint Presentation .ppt /.pptx), PDF File .pdf), Text File .txt) or view presentation slides online. PPT on pedal powered zeolite refrigerator which works on vaccum and zeolite.
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As it is powered by heat, the adsorption-based cooling process can utilise a range of different energy sources. Mobile freezer boxes are already being tested in. of vacuum pump and refrigerator will be able to satisfy the cooling needs, thereby Index Terms-- Zeolite, Vaccum gauge, Digital temperature sensor, Vaccum pump .. The pump could have been driven by pedaling a bicycle i.e it can be. The design and production of a solar powered Zeolite-water adsorption refrigerator using concentrating parabolic collector (CPC) was done. An array of two.
Together with water filtering and agriculture being more related to the lines of interest with the Energetic forum types. Coupled together with current Thermal Solar techniques, and related technologies this unrefined form of energy, heat and its storage could be big revolution. A friend of mine is having a DIY go at this, stay tuned.
Please add your insight, knowledge or experience with the mineral Zeolite. Scientists of the German Fraunhofer Institute have harnessed a natural phenomenon to store heat indefinitely and without energy loss. Zeolite is a mineral that can store up to four times more heat than water. Zeolite is extremely porous. So much so, that a gram of the stuff has a surface area of a 1000 square meters 10,764 sq ft.
When water comes into contact with zeolite it is bound to its surface by means of a chemical reaction which generates heat.
Reversely, when heat is applied the water is removed from the surface, generating large amounts of steam. The transference of heat to the material does not cause its temperature to rise. Instead, the energy is stored as a potential to adsorb water. Some of the designs are from the applied patents and some are from the recent literatures. The fin patterns include interrupted surfaces, enhanced wavy and the vortex generators.
Benefits and the associated constraints of these designs are discussed. F Tsai A three-dimensional numerical study was conducted to assess the heat transfer performance of extended fins in a two-row finned tube heat exchanger. Fins under investigation were plane and slit types. A finite volume discretization method and a SIMPLE-based solution algorithm were, respectively, applied to working differential equations and their discrete counterparts to compute the gas velocities and pressure.
Ding . A circuit data structure circuit connection network for a general description of different circuit configurations in computer programs is presented.
On basis of this data structure, a general tube-by-tube simulation model and the corresponding code for prediction of plate fin-and-tube heat exchanger performance are developed. Dimensional Parameters Threaded tube mm Straight Tube mm Aluminium Aluminium Length of the heat exchanger 1000 1000 Inner diameter of the inner tube, di 16 16 Outer diameter of the inner tube, do 26 25 Inner diameter of the outer tube, Di 36 36 Outer diameter of the outer tube, Do 42 42 Pitch distance between threads 2.
Manufacturing and fabrication of threaded tube. Insertion of simple instrumentation for thermal measurement. Study of variation of Reynolds number on the Nusselt number. Reduction of data to construct useful heat transfer correlations. A schematic diagram of the experimental apparatus is shown in Fig 1. The test loops consists of a test section, hot water loop, cold water loop and data measuring systems. Schematic Diagram 1. Suction Pipe 2. Heaters 3. Cold Water Pipe 4. Hot Water Sensor 5. Cold Water Sensor 6.
Cold Pipe Outlet 7. Threaded Heat Pipe. S Outer Pipes 9. Non Threaded Heat Pipe 10. Delivery Pipe 11. FCV 12. Cold Pipe Inlet The test section is the water-to-water single-phase horizontal double pipe heat exchanger with two different configurations of the inner tube threaded and non threaded. In result table, LMTD, overall heat transfer coefficient, Nusselt numbers across the inner tube are calculated. The collected data is processed, analyzed and presented Reynolds number 1500 — 31000 range and mass flow rates 0.
The readings and observations are taken prior to calculation of above mentioned parameters In present work, experimentation is done for single-phase water to water tube in tube heat exchanger with threaded and non threaded inner pipe. This analytical work is further studied in detail and presented. Effect of Nusselt Number on inner tube side Reynolds Number for different configurations of the inner tube threaded and Straight Fig 5.
Fig 6. Fig 7. Variation of inner tube Nusselt Number with Reynolds number for threaded and Straight tube for cold 400 LPH Effect of Convection coefficient for different configurations of the inner tube threaded and Straight Fig. Fig 9. Variation of inner tube Convection coefficient with Threaded and Straight inner tube flow rate for cold 400 LPH Qavgfor different configurations of the inner tube threaded and Straight Fig 11. Fig 12. It is observed from the graph that the heat transfer rates of threaded pipe are more as compared to non- threaded pipe, keeping the cold flow rate LPH constant.
It is also observed from the graphs, that heat transfer rate for threaded pipe is more than non-threaded pipe for respective cold mass flow rate. It is clear that the Nusselt Number of inner tube increases with increasing flow rate of water through inner tube. A two to four times more heat transfer enhancement is observed experimentally for the aforesaid heat exchanger with increased pumping power requirement of twice or thrice.
Thus this work concludes that significant heat transfer enhancement is achieved for the threaded inner tube in TTHE. The work can be extended further for heavy heat duty industrial applications with wide operating conditions, different fluids and more precise instrumentation, provided that time and money are not constraints. Ding, J. Fan, Y. He, W. Tao, Y. Zheng, Y. Gao, J. Jafari Nasr and A. Gbekeloluwa B. Sunflower seed hull was milled and treated with 0. The sorption kinetic properties were studied using pseudo first and second order, and Elovich model.
The equilibrium data best fitted the Langmuir model while the sorption kinetic data were successfully described with pseudo- second order model for DSSH.
These synthetic dyes have complex molecular structures, which make them more stable and difficult to biodegrade. Several research reports reveal that very small quantities of dyes are highly toxic and can cause acute disorders in aquatic organisms. Uptake of effluents through food chain in aquatic organisms and human beings may cause various chromosomal fractures, respiratory, mutagenic and carcinogenic problems. Therefore, wastewater containing dyes must be appropriately treated before being discharged into the water bodies.
However the application of the above mentioned technologies is sometimes restricted due issues including; incomplete dye removal, requirement of expensive equipment and monitoring systems, high reagent or energy requirements or generation of toxic sludge and other waste products. Adsorption, the adhesion of molecules to a surface, has been found to be an efficient and economic process to remove dyes and other contaminants from aqueous solutions. Presently, activated carbon has been the most widely used as an effective adsorbent for the removal of dyes because of its high adsorption capacity, surface area and atmospheric properties.
However, there are certain disadvantages of using activated carbons namely its high usage or operating costs and regeneration issues [Akar et al. Consequently, a considerable amount of studies have been carried out on the development of effective, low cost and easily available alternative biosorbents.
Different agricultural biomass such as saw dust Shukla et al. The sunflower plant is a native of North America. It was grown by the Indians for food in North Carolina before 1600 and by New England colonists for hair oil as early as 1615.
Sunflower grains are botanically defined as fruits. Today, Sunflower is the fifth most important source of edible oil after soybean, rapeseed, cotton, and peanut. The total world production of 25. The rising prominence of sunflower oil in world edible oil markets has stimulated an expansion in U.
Sunflower seed hulls are discarded as waste during industrial process of oil extraction and thus a large amount of sunflower hulls is generated each year.
Sunflower hulls have little commercial value and become a disposal problem owing to their 21 The Potential Use of Acid Treated… low bulk density, hence the utilization of such agriculture solid waste for wastewater treatment is most desirable[NASS, 2012]. The purpose of this study is to investigate the potential of the use of an agricultural waste material, such sunflower seed hull, as an alternative, cost effective biosorbent for the removal of dye from aqueous solutions. The effects of several parameters such as pH, adsorbent dosage, temperature, and initial dye concentration were investigated.
The sunflower seed hulls were then sieved through the ASTM 20 standard sieves. The effect of acid treatment was studied. Another 20g of sunflower seed Hulls was soaked in 1000ml of 0. Both solutions were then left overnight. The treated material was washed several times with distilled water until the pH of the supernantant was at a pH of above 6. The washed Sunflower seed hull was then dried at about 100 oC for about 3 hours and stored in labeled zip-lock bags until further use.
Preparation of dye effluent solution Concentrated dye effluent was obtained from Cotton Incorporated Cary, North Carolina. The total solid concentration of the dye solution was 73. Batch Adsorption Experiments The maximum absorbance was observed at 620 nm and was used in all experiment. The concentration of dye effluent was determined from a calibration plot of absorbance at 620nm versus concentration.
Batch adsorption of dye onto the adsorbent was conducted in aqueous solutions under different operating conditions viz. Batch adsorption equilibrium studies were carried out in 50 mL plastic tubes containing known concentration of dye at 25 oC. Dye solutions 20 ml each were regularly vortex with an optimum adsorbent dosage and at optimum pH.
The batch adsorption kinetic studies were carried out on a solution of different initial dye concentrations with an optimum dosage at the optimum pH and at 25 oC.
The adsorption kinetic data was applied to the pseudo-first-order, pseudo- second- order and Elovich model Tsezos, M. The pH of the solution is one of the most important operating parameters that affect the adsorption of dye [Donghee Park 2010. The pH influences surface properties of the biosorbent by way of functional group association and surface charges. The results shown in figure 2 revealed that the removal of dye increased with an increase in DSSH dosage. This may have been as a result of the increase in number of active sites on the adsorbent surface with increasing dosage amount, resulting in an increase in dye removal.
This may be due to a reduction in the concentration gradient of the dye molecules. Effect of Temperature on adsorption The effect of temperature on adsorption is shown in figure 3. The results indicate that there was an increase in biosorption with an increase in solution temperature. Furthermore, increasing the temperature may produce a swelling effect within the internal structure of the Sunflower seed hull which enables dyes to penetrate further.
As can be seen from the figure the removal of dye decreases with an increase in dye concentration. This may be due to the saturation of the available active sites on the sunflower seed hull, beyond a certain concentration of dye. For a fixed amount of sunflower seed hull at a low dye concentration, adsorption of the dye proceeds faster due to less number of dye ions in the solution. As initial concentration increased, the number of dye ions in the solution increases against a fixed amount of available active sites, thus leading to a decrease in dye removal with an increase in initial dye concentration Khataee et al.
Figure 4. These provide more important parameters for designing and optimizing of the biosorption systems. Different isotherm models can be used to determine the biosorption characteristics of a biosorbent. In the present study the textile wastewater dye biosorption was analyzed by three different models Langmuir, Freundlich and Dubinin—Radushkevich D—R. The data were fitted and the calculated isotherm constants are presented in Table 1. Once a biosorbate occupies a binding site, no further biosorption occurs at this site.
In other words Langmuir model assumes that biosorbed layer is one molecule thickness monolayer biosorption Langmuir , 1918. RL is calculated by using Equation 3. The value of RL calculated using the above equation is incorporated in Table 1. If the RL values lie between 0 and 1, the biosorption process is considered to be favorable Hall et al. Values of KL and qmax are obtained from the intercept and slope of the linear plots at various dye concentration in Figure 5 and are represented in Table 1.
The RL values in this study were in the range 0. The Freundlich isotherm is an empirical equation assuming that the adsorption process becomes on heterogeneous surfaces and adsorption capacity is related to the concentration of Azure dye at equilibrium. Values of KF and n are obtained from the intercept and slope of the linear plots at various dye concentration in Figure 6 and are shown in Table 1.
The numerical values of Freundlich constant of n was 8. It is greater than unity indicating that textile effluent dye is favorably adsorbed by DSSH. The Dubinin—Radushkevich D—R isotherm is more general than the Langmuir isotherm since it does not assume a homogeneous surface or constant biosorption potential Dubinin and Radushkevich, 1947. The D—R isotherm model describes the biosorption nature of the sorbate on the biosorbent and it is used to calculate the mean free energy of biosorption.
The characteristic biosorption curve is related to the porous structure of the biosorbent according to this model.
The mean free energy of biosorption E was calculated to be 6. According to the correlation coefficient r2 values in Table 1 the Langmuir model was determined to be the best fit for this experiment and thus better describes the adsorption of dye onto DSSH.
Figure 5. Figure 6. The rate of adsorption characterizes whether the DSSH is a good economical operational treatment process for dye effluent. The actual rate of adsorption of dye ions can vary from a few seconds to several minutes to reach equilibrium, which is dependent on the several properties of this adsorbent. Kinetics of adsorption on the dried sunflower seed hull DSSH was analyzed using pseudo first-order, pseudo second-order, and Elovich Model. The first-order rate equation can be written as follow Kirani et al.
It was found that the correlation coefficients for the first-order model are lower than that of the pseudo-second-order model. This implies that the biosorption process does not follow first-order kinetics. The pseudo-second-order kinetic model Kirani et al. These parameters are summarized in Table 2.
The calculated q2 values agree with experimental q values and the correlation coefficients for the pseudo-second order kinetic 27 The Potential Use of Acid Treated… plots were very high.
These results suggested that the biosorption system studied follows to the pseudo-second order kinetic model. This suggests that the adsorption of dye onto the surface of DSSH is due to physicochemical interactions between the two phases Tsezos, M. The simplified Elovich equation is generally expressed as Akar et al. Figure 9. Table 2.
The optimum biosorption conditions were determined , such as pH, biosorbent dosage. Biosorption of textile effluent dye increased with a decrease in the pH of the solution. Biosorption also increased with increase in biosorbent dosage as well as increase in temperature, but decreased with increase in initial dye concentration.
Biosorption process followed the pseudo second-order kinetic model and Langmuir isotherm model under the studied concentration range. Akar, S. Gorgulu, A. Decolorization of reactive Blue 49 contaminated solution by Capsicum annuum seeds: Batch and continuous mode biosorption applications Chemical Engineering Journal 168: 125 -133.
Biosorption of a reactive textile dye from aqueous solutions utilizing an agro-waste. Desalination, 249: 757-761. Annadurai, G. Use of cellulose-based wastes for adsorption of dyes from aqueous solutions.
B92: 263—274. Bailey, S. A review of potentially low-cost sorbents for heavy metals. Water Res. Chern, J. Desorption of dye from activated carbon beds: effects of temperature, pH and alcohol. Chou, K.
The adsorption of Congo red and vacuum pump oil by rice hull ash. Crini, G. Application of chitosan a natural aminopolysaccharide for dye removal from aqueous solution by adsorption processes using batch studies: A review of recent literature. Progress in polymer Science, 33:399-447.
Donghee Park. Biotechnology and Bioprocess Engineering, 15: 86-102. Dubinin, M. Freundlich, H. Helfferich, F. Ho, Y.
Removal of basic dye from aqueous solutions using tree fern as a biosorbent. Process Biochem. Khataee, A. Biological decolorization of C. Basic Green 4 solution by Chlorella sp. Chinese J. Biological treatment of a dye solution by Macroalgae Char asp. Bioresource Technology, 101: 2252-2258. Khattri, S. Color removal from dye wastewater using sugar cane dust as an adsorbent. Kirani, I. Biosorption kinetics and isotherm studies of Acid Red 57 by dried Cephalosporium aphidicola cells from aqueous solutions.
Biochemical Engineering Journal 31:197—203 . Langmuir, I. Malik, P. Dye removal from wastewater using activated carbon developed from sawdust adsorption equilibrium and kinetics, J.