Progressive Freeze Concentration of Coconut Water: Effect of Coolant Temperature on Process Efficiency and Heat Transfer

2014 ◽  
Vol 695 ◽  
pp. 447-450
Author(s):  
Safiei Nor Zanariah ◽  
Mohamed Nor Noor Naimah ◽  
Norzita Ngadi ◽  
Zaki Yamani Zakaria ◽  
Jusoh Mazura

In this research, coconut water was concentrated by applying progressive freeze concentration (PFC) using coil crystallizer. Overall heat transfer coefficient (U) was analyzed from the process by varying different coolant temperature values since both of them are closely related. In this case, heat transfer efficiency depends strongly on ice crystal formed on the inner cooled surface and is explained theoretically from that angle. At optimum flowrate, operation time and initial concentration best results were observed at-10oC of coolant temperature where the concentration efficiency and effective partition constant (K) obtained were 48% and 0.2 respectively. Meanwhile, U obtained at the first and second stages were 183.0046 W/m2oC but dropped at lower value at later stage at 154.9625 W/m2oC due to ice fouling.

2015 ◽  
Vol 74 (7) ◽  
Author(s):  
Norshafika Yahya ◽  
Zaki Yamani Zakaria ◽  
Noorhalieza Ali ◽  
Mazura Jusoh

In this paper, raw material of refined bleached and deodorised palm oil (RBDPO) was separated into olein and stearin by applying progressive freeze concentration (PFC) as an alternative method to replace the conventional fractionation process using coil crystallizer. Overall heat transfer coefficient (U) was analyzed from the process by varying different coolant temperature values since both of them are closely related each other. In this case, heat transfer efficiency depends strongly on crystal of stearin formed on the inner wall of cooled surface and is explained theoretically from that angle.  At optimum flowrate, operation time and initial iodine value (IV), the best results were observed at 28ºC of coolant temperature where high IV of olein and effective partition constant (K) obtained were 55.8 wijs and 0.27 respectively. Meanwhile, the highest U obtained at coolant temperature 28oC same as result for process efficiency at 392.9183 W/m².K and time at 55 min.


2015 ◽  
Vol 15 (3) ◽  
pp. 625-631 ◽  
Author(s):  
Farah Hanim Ab. Hamid ◽  
Norfatiha A. Rahim ◽  
Anwar Johari ◽  
Norzita Ngadi ◽  
Zaki Yamani Zakaria ◽  
...  

In this century, the shortage of clean water supply is an issue of concern and the problem is expected to become more serious in the future. Consequently, researchers are trying to find the best solution to address this problem by introducing new desalination technologies that are able to accommodate the increasing demand for clean water. One of the new technologies introduced is desalination of seawater through freeze concentration. In this study, progressive freeze concentration (PFC) was implemented to produce pure water in the form of an ice crystal block, leaving behind higher concentration seawater using a coil crystallizer. The effect of operating parameters such as initial concentration and coolant temperature were investigated. Meanwhile, the efficiency of the system was reviewed based on the value of the effective partition constant K which is defined by the ratio of solute in ice and liquid phase. A low value of K indicates when the system is most efficient. In addition, the results for the overall heat transfer coefficient are also presented to observe the heat transfer involved in the system.


2014 ◽  
Vol 695 ◽  
pp. 443-446 ◽  
Author(s):  
Ab. Hamid Farah Hanim ◽  
A.Rahim Norfatiha ◽  
Norzita Ngadi ◽  
Zaki Yamani Zakaria ◽  
Jusoh Mazura

The world is still suffering from a shortage of clean water supply and the problem is expected to become more serious in the future. Consequently, researchers have been trying to find the best solution to address this problem by introducing new desalination technologies that are able to accommodate the demand for clean water which is increasing from time to time. One of the new technologies introduced is the desalination of seawater through freeze concentration. In this study, progressive freeze concentration (PFC) is implemented to produce pure water in the form of ice crystal block and leave behind a higher concentration solution. The effect of coolant temperature was investigated and the efficiency of the system was reviewed based on the value of effective partition constant, K which is defined by the ratio of solute in ice and liquid phase. The low value of K leads to the best efficiency for the system. Apart from that, the efficiency, E% and salinity reduction were also calculated in order to determine the system performance.


2014 ◽  
Vol 695 ◽  
pp. 451-454 ◽  
Author(s):  
Amran Nurul Aini ◽  
Samsuri Shafirah ◽  
Norzita Ngadi ◽  
Zaki Yamani Zakaria ◽  
Jusoh Mazura

Behaviours of ice crystal growth at two different operating parameters namely coolant temperature and circulation time were investigated for progressive freeze concentration (PFC) of glucose solution through a vertical finned crystallizer (VFC). Two determinant parameters which are ice production rate (mu), and water recovery (WR) were used to illustrate the behaviours of ice crystal growth in this study. From the result, higher ice production rate (mu) and water recovery (WR) were achieved at lower coolant temperature. On the other hand, longer circulation time resulted in lower ice production rate (mu), but at the same time increased the water recovery (WR). The maximum ice production rate (mu) and water recovery (WR) attained through this study were 1.522 gm-2s-1 and 51.131 %, respectively.


2014 ◽  
Vol 67 (2) ◽  
Author(s):  
Mazura Jusoh ◽  
Noor Naimah Mohamed Nor ◽  
Zaki Yamani Zakaria

In order to provide convenience for consumers around the world, it is highly beneficial if the nutritious coconut water (CW) could be concentrated and just easily be added with water for later consumption. A new concentration technique is required to eliminate some parts of the water from the CW while retaining its nutritious and unique aroma. As Progressive Freeze Concentration (PFC) could retain the nutritional compounds, it was applied to concentrate CW and reduce its volume. In PFC system, only a single block of ice is formed as a layer on the cooled surface. A coil stainless steel crystallizer was used as FC unit to investigate the enhancement of sugar content in CW. The effect of initial concentration of CW was then investigated on the performance of the PFC system through the Effective Partition Constant (K) value and increment of sugar content. It was found that low initial concentration and intermediate coolant temperature yielded lower K value and high increment of sugar content. The best K achieved was 0.3101 and the highest increment of sugar content was 53% at initial concentration of 3 %Brix and coolant temperature of 12°C.


2014 ◽  
Vol 67 (3) ◽  
Author(s):  
Mazura Jusoh ◽  
Noor Naimah Mohamed Nor

Progressive freeze concentration integrated with a coil crystallizer was applied to concentrate coconut water in order to increase its sugar content. In progressive freeze concentration system, only a single ice is formed as a layer on cooled surface. It is introduced as an alternative in compensating the disadvantages of conventional method of freeze concentration, called suspension freeze concentration. In this research, the efficiency of the progressive freeze concentration system was determined through effective partition constant (K) value and percent increment of sugar content. Hence, the effect of circulation flowrate ranging from 2000 to 2800 ml/min and circulation time from 10 to 18 minutes on those two variables was then investigated through experiments designated using one factor at a time. From the experimental work, it was found that higher efficiency results at higher circulation flowrate of 2800 ml/min based on lower K and high percentage of sugar increment achieved. It was also found that the percentage of the sugar increment is high when the period given for circulating the solution is increased and the most suitable circulation time is 14 minutes.


2019 ◽  
Vol 797 ◽  
pp. 55-64 ◽  
Author(s):  
Farah Hanim Ab Hamid ◽  
Siti Nurajjar Jami

Crystallization technique is one of the potential techniques to deal with wastewater treatment. In this work, progressive freeze concentration (PFC) technique was studied for its effectiveness in wastewater treatment from food industry. In PFC, pure water is produced in the form of ice crystal block and leave behind a higher concentration solution. The effect of coolant temperature and stirring speed on the effective partition constant (K) and solute recovery (Y) were investigated. Glucose solution was used as simulated wastewater sample. The best conditions were found at the moderate coolant temperature of -10°C and maximum stirring speed of 500 rpm, resulted in the lowest K value and highest Y, lead to the highest efficiency on the wastewater treatment.


Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1621
Author(s):  
Guangyi Pu ◽  
Xiaoyin Li ◽  
Fangyang Yuan

The heat transfer efficiency of a regenerative thermal oxidizer with three canisters used for volatile organic compounds treatment was studied using numerical simulation methods. A one-dimensional model that took into account the variation of physical parameters with temperature was built. The results show that the preheating temperature and outlet temperature tend to be stable as the operation time is increased. The heat transfer efficiency of equipment was mainly evaluated by heat recovery efficiency and energy recovery ratio under steady state conditions, which was affected by the inlet gas flow and temperature, valve switch time, combustion temperature, materials and porosity of the regenerative medium, and packing height. With the increase in packing cross-sectional area and packing height, the increase in heat transfer efficiency leads to an increase in equipment cost. Simultaneously, the shorter the valve switch time and the higher the density of the regenerative medium battery also help to improve the heat transfer efficiency without blocking equipment. Unless the removal efficiency of volatile organic compound treatment is reduced, it is recommended to reduce the inlet and combustion temperatures.


2021 ◽  
Vol 23 (1) ◽  
pp. 97-110
Author(s):  
Terang UHSG Manik ◽  
Tulus Burhanuddin Sitorus ◽  
Mangontang Situmorang

In heat exchanger analysis using the Earth Air Heat Exchanger method, the overall heat transfer coefficient is known. This tool uses tubes in its design. The weakness of tube and plate type heat exchangers is the relatively low heat transfer coefficient, which can only reach a maximum of 60%. Therefore, a method to improve the heat transfer efficiency is using a fin. The purpose of this study is to calculate and compare the effectiveness (ε) value of experimental and theoretical of the Earth Air Heat Exchanger, as well as to find out the value of the coefficient of performance. The result showed that the average COP value of the experimental result is 0.63 at a speed of 1 m / s, 0.54 at the speed of 2 m / s, and 0.75 at the speed of 3 m / s, while theoretically is 0 , 73 at 1 m / s, 0.57 at 2 m / s, and 0.80 at 3m / s. For the value of the average effectiveness of the experimental results obtained 0.85 at the speed of 1 m / s, 0.93 at the speed of 2 m / s, and 0.89 at the speed of 3 m / s, while the theoretical result is 0.995 at the speed of 1 m / s, 0.997 at 2 m / s, and 0.998 at 3 m / s.


Author(s):  
Yu. P. Morozov

Based on the solution of the problem of non-stationary heat transfer during fluid motion in underground permeable layers, dependence was obtained to determine the operating time of the geothermal circulation system in the regime of constant and falling temperatures. It has been established that for a thickness of the layer H <4 m, the influence of heat influxes at = 0.99 and = 0.5 is practically the same, but for a thickness of the layer H> 5 m, the influence of heat inflows depends significantly on temperature. At a thickness of the permeable formation H> 20 m, the heat transfer at = 0.99 has virtually no effect on the thermal processes in the permeable formation, but at = 0.5 the heat influx, depending on the speed of movement, can be from 50 to 90%. Only at H> 50 m, the effect of heat influx significantly decreases and amounts, depending on the filtration rate, from 50 to 10%. The thermal effect of the rock mass with its thickness of more than 10 m, the distance between the discharge circuit and operation, as well as the speed of the coolant have almost no effect on the determination of the operating time of the GCS in constant temperature mode. During operation of the GCS at a dimensionless coolant temperature = 0.5, the velocity of the coolant is significant. With an increase in the speed of the coolant in two times, the error changes by 1.5 times.


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