The author wishes to acknowledge all his lecturers at the Department of Construction and Engineering, KUET. In the context of the crisis, solar desalination seems to be the most suitable solution to the salinity problem of the coastal areas of Bangladesh.
INTRODUCTION
- Scope of the Study
- Organization of the Report
- Definition of Desalination Process
- Historical Background
In this study, the evaporation surface of the sun was still taken into account and a way was sought to increase it. Various parameters of the distillate were determined and the durability of the textiles was also investigated in different salinities.
At the same time, some research into solar distillation was carried out in the USSR (Tekutchev, 1938). In the second case (ion exchange), ions are trapped in the solid matrix of the resin.
15 some thematic discussions on other desalination technologies will also be presented in the
This temperature is controlled by controlling the pressure in the vapor space of the evaporator. Compressing the vapor increases both the pressure and the temperature of the vapor.
19 compression of the vapor increases both the pressure and temperature of the vapor, it is
These two points led to the separation of the two functions (cooling and production). Vapor developed from the feed solution passes through the pores of the membrane and is collected on the other side.
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Summary Discussion
ED is the most energy-efficient desalination method for brackish water with low nonionic solute content, while RO can be used for brackish or seawater if the water has a low membrane fouling potential. Batteries are often proposed and actually used to solve this, but batteries are very problematic in the field. 38 But water scarcity worldwide, particularly in the coastal areas of Bangladesh, points to an urgent need to develop low-cost, small-scale household desalination technology that uses renewable energy sources.
This solar desalination technology could make a quite appropriate contribution to providing safe drinking water in the coastal areas of the world. These conditions have pushed researchers to invest their significant efforts in the study of alternative, non-conventional means of obtaining water in preparation for droughts, such as wastewater treatment, desalination or exploitation of deep groundwater, as well as the development of tools and strategies. for conjunctive management and water saving that allow optimizing the management of water resources and avoiding periods of scarcity.
CHAPTER 3: Methodology
- General
- Experimental Setup
The average duration of bright sunshine (Figure 3.2.1 and Figure 3.2.2) in Bangladesh in the dry season is about 7.6 hours per day, and in the monsoon season it is about 4.7 hours. Aluminum wire of arbitrary length is taken to make the spring as well as the cylindrical shape using a hollow iron cylinder of about 10 cm diameter. A flexible spring-like frame and a complete cylindrical frame are shown in Figure 3.3.3 and Figure 3.3.4, respectively.
The textile cover is also a cover of cylindrical shape, which was used to make the surface from which the evaporation takes place. To make a textile cylinder, an aluminum frame was inserted into a cylindrically shaped textile cover and.
44 extended chords have been ejected through the centre of the top cover. After that the top
Assembling of Experimental Setup
A drill hole with a size smaller than the outer diameter of the PVC pipe was made in the bottom of the vessel to fit the distillation collection pot and was the outer periphery layer of the pipe and the drill hole. In each placement, two plastic pots were used with the lower one placed upside down to make a flat and stable surface for the upper bucket. The upper bucket is placed on the rooster sheet and a hole is made in the wall of the upper bucket from 2 cm below its top.
This hole was detected by considering the smooth discharge of overflow water from the upper bucket. The upper and lower parts of the container are set to its original shape and the joint is carefully waterproofed and airtight by the use of glue.
NOW-
Water Tightness Testing
Before carrying out, the watertightness of the setup was examined at the top pot hole, the hole in the lower part of the clear plastic container and also at the cutting joint of the setup. The manufacturing procedure has been described in the previous articles. Any of the above leakages can affect the quality of the distillate and its production rate and from this point of view, water tightness testing was very important in this study. This test was quite important for the overall research and was conducted in the environment.
The pot is then filled to the top with tap water and kept for several hours. The watertightness test for the assembly of transparent plastic container is done before driving.
Sampling Program
All setups are placed on the wooden deck and filled with tap water. The entire water setup had been monitoring for several hours whether it was leaking or not. The hourly production rate of distillate was • Initially, the surface of textiles taken once a week from morning to cylinder remained dry after wetting and.
The raw water was collected in time after the wetting was done as carefully as the wetting of the textile cylinder and the parameters of the entire surface of the textile cylinder were tested in the laboratory.
Data Collection and Analysis
General
Variation of Distillate Production Rate (DPR)
To make the investigation clearer, a parallel monitoring replica was installed and these capabilities were presented in Figure 4.2.3 and 4.2.4 for the month of January 2011. Both Figure 4.2.5 and Figure 4.2. 6, the slope of all trend lines is positive, which means that DPR was increasing in the month of January 2011, but the slope was not the same for all settings. This setup ran from early February to November 2011 and the DPR version was presented for all setups in Figure 4.2.5 and 4.2.6- below.
From Figure 4.2.9 and Figure 4.2.10 it can be seen that for both settings the trend lines are almost flat, meaning that the DPR was equally varied during this month. For the month of June 2011, all settings yielded the comparable nature of the curve shown in Figure 4.2.19-22 below.
Effective
A summary of the sequence and physical changes to the setup were presented in Table 4.2.3 based on the distillate production rate.
Replication of the Setup
Modification of the selected
Selection of Textile for
- Temperature Variation
- Water Quality Monitoring
The salinity of the distillate was measured by the hydrometric and argentometric method according to the 191)1 edition of the Standard Method for the Examination of Water and Wastewater. The test continued from January 11 to June 11 and the level of distillation salinity for All, Bil and C I shown in Figure 4.4.1 below and the others are presented in Annex-Ill. The pH of the distillate was measured using the MACH brand pH Meter model-sensIONi and Multi-Meter model-senslON 156.
Most measurements were within the range of the drinking water standard limit (6.5-8.5), while some were below the range. Two figures 4.5.1 and 4.5.2 are shown, which show the physical condition of the plastic container at the time of the start and end of monitoring, respectively.
68 seemed to be dimmed but its serviceability was as good as new one. From this circumstance,
Variation of Different Parameters
The hourly DPR is monitored one day a week for several months and is shown in the following figures 4.6.1 and 4.6.2. The DPR is gradually increased and becomes maximum from 12:00 to 14:00, shown in both figures. It was monitored continuously, but is shown in Figure 4.6.3 during the hourly DPR monitoring period.
Similarly, another day data analysis has also been depicted in the following discussion. The temperature was measured at the surface of the textile cover and the air in the setup including ambient.
74 temperature and 13.680C for ambient and air temperature in the setup. It was the significance
Installation of Textile Cylinder Desalination Unit (TCDU)
Before installing the system, its size must be specified according to the demand for drinking water and that the quantities depend on the size of the family and the weather conditions. According to this estimate, the Ilimily nce of a living member (1 the maximum amount of drinking water is 15 L/day. But from the results and discussions, the maximum amount of distillation has been 0.25 lJcla in the summer season and the minimum 0.10 L/day in the winter season where the cross-sectional area was only 245 cni', the evaporation surface 990 cm2 and the condensation surface 1920 c1112.
Since there is no chloride concentration (Cl') present in the distillate, but the concentration limit for chloride (Cl') in drinking water is 1000 mg/l for coastal areas of Bangladesh where alternative sources are not available, this chloride (Cl') can therefore also consider increasing the size. The overall system is sufficiently secured to protect against wind gusts and other unexpected events.
Operation of the Textile ('under Desalination Unit (TCDU)
So the number or size of TCDU is specified by considering two-thirds concept. After fixing the shape and model, the TCD system is installed in a safe place where the sunlight keeps its shine all day long. The life of the device depends on the proper maintenance, which is discussed in the next article.
Maintenance of Textile (''linder Desalination Unit (TCDU)
Conclusions and Recommendations
- General
- Conclusions
- Recommendations
Most of the textiles became completely dry olI within the fifth clay from the beginning except B 11 where it became ninth day. After one year of continuous work, the physical form of the buckets was totally unchanged and it would be possible to use about 03 years continuously by doing proper maintenance. After one year of continuous processing of the textile fibers, its physical condition was not significantly depicted and its interior also looked like a new one.
From the hourly DPR and temperature analysis. the DPR was increased with the increase of temperature hut the peak of the temperature occurred first and then the peak for DPR. Relative humidity of the air can also be included in this study for a comprehensive investigation. Water Science and Technology Board, National Research Council (NRC) of the U.S. 2001), Utilization of new technique to further improve the efficiency of horizontal solar clesalniation, Desalination.
An Overview of Modern Technologies and Research on Desalination Linked to Reneuah/e Energies, Proceedings of the NATO Advanced Research Workshop on Solar Desalination for the 21st Century Hammamet, Tunisia 23--25 February 2006.
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