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Removal of Free Fatty Acids and Impurities from Palm Oil for Use in Bio-Transformer Oils
(2024-01-01)
Phoongen, Fariz
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Thongboonchoo, Narisara
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Lertweeranontharat, Chanaphat
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Kitchaiya, Prakob
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Mantree, Nattapong
This research aims to study the removal of free fatty acids (FFA) in palm oil to make it suitable for use as transformer oil using the adsorption method. The adsorbent used in this study is hydrogels of amorphous silica. The experiments were conducted by varying the following conditions: adsorbent modification, adsorbent type, adsorbent dosage, temperature, and adsorption time. The adsorption kinetics and equilibrium were studied. The equation for estimating the required amount of adsorbent at different temperatures was developed. It was found that 3 grams of adsorbent per 100 grams of oil were required to reduce the FFA content from 691.64 to 44.53 ppm at room temperature (30°C) and an adsorption time of 1 hour and 30 minutes. This achieved the desired target of reducing the FFA content to below 50 ppm. The analysis of the chemical composition of each fatty acid before and after adsorption using the HPLC technique showed that each type of FFA, including palmitic acid, stearic acid, oleic acid, linoleic acid, and eicosanoic acid, was significantly reduced. The adsorbent was equally effective in removing each type of FFA. The electrical properties of palm oil before and after adsorption were tested. It was found that the palm oil after adsorption had a breakdown voltage of 50 kV and 61.3 kV at a test gap of 2 mm, and 32.6 kV and 37.3 kV at a test gap of 1 mm, respectively. This shows that the reduction in FFA resulted in an increase in the breakdown voltage. This increase makes the use of palm oil as a liquid insulation in transformers more efficient and safer.
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Scrubbed Palm Fatty Acid Distillate as Vitamin E Concentrate
(2022-01-01)
Soontornchatchawate, Amnart
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Chintanalert, Supachai
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Kitchaiya, Prakob
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Namkanisorn, Apinan
Vitamin E (VitE) production from crude palm oil (CPO) has been extensively studied and industrially conducted. VitE in CPO is in the range of 600 to 1,000 ppm, and is usually produced from one of the main by-products of edible palm oil production, namely palm fatty acid distillate (PFAD). PFAD contains 4,000 to 5,500 ppm of VitE, and is produced from deodorization process of palm oil purification. This paper presents an innovative process of VitE concentrate production from CPO. A scrubber was designed and installed between the deodorizer and conventional PFAD scrubber. The main objective of this new scrubber was a recovery of glycerides from PFAD. This new scrubber is operated at 150 to 160℃. The scrubbed oil is named as Scrubbed Palm Fatty Acid Distillate (S-PFAD). This simple and efficient modified process can retrieve glycerides as S-PFAD at 0.3% recovery and it enhances VitE concentration in S-PFAD to the range of 28,000 to 32,000 ppm, which is the highest concentration of VitE that has ever been produced in the palm oil production. Fatty acids and glycerides in S-PFAD were esterified and transesterified to methyl esters. The methyl esters were evaporated from S-PFAD, and S-PFAD residue oil contained 24.7% VitE.
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Theoretical study on a novel temperature breakpoint cyclic operation to enhance desiccant packed bed performance
(2021-08-01)
Murathathunyaluk, Siripan
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Kitchaiya, Prakob
In a conventional desiccant packed bed dehumidification, the adsorption and desorption operations switched at a constant cycle. However, this Conventional Steady Cyclic (CSC) operation was not performed well under disturbances. Therefore, a Temperature Breakpoint Cyclic (TBC) operation is proposed. A numerical model of the desiccant packed bed dehumidification system has been constructed and validated. The model was then used to assess the desiccant packed bed dehumidification performances in term of moisture removal capacity (MRC) and dehumidification coefficient of performance (DCOP) under various cycle times and temperature factors. The calculation results showed that under CSC, larger amounts of energy were required in the desorption operation, while the TBC exhibited higher performances in term of both MRC and DCOP. Notably, at a high regeneration temperature, the MRC of the TBC was 10% higher than the CSC's; moreover, the DCOP of the TBC was twice higher than the CSC's. In other words, at high recovery temperature, both operations exhibited comparable capacities while the energy cost was halved under TBC operation.
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Effect of antimony trioxide and carbon black on the mechanical properties and ablation properties of liner insulation in rocket motors
(2021-01-01)
Kitinirunkul, Thirapat
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Kitchaiya, Prakob
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Kiriratnikom, Chesda
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Boonyarat, Paisarn
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Nuanklai, Suchuchchai
This study focused on the mechanical properties and ablation properties of liner insulation in rocket motors for improving rocket performance by means of tensile strength, elongation, ablation rate and density. The following parameters were varied: amount of zinc oxide, antimony trioxide and carbon black (N550). It was found that the insulation of the rocket motors with antimony trioxide and carbon black provided higher the elongation and ablation rate. Thus, it was able to endure more heat from hot gas in combustion chamber. The result suggests that use of antimony trioxide and carbon black as filler in liner insulation can improve the thermal insulators and case-bonded in rocket motor between the solid propellant and the rocket motor tube.
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Bench scale production of vitamin e from crude palm oil
(2021-01-01)
Soontornchatchawate, Amnart
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Wattananusorn, Santi
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Kitchaiya, Prakob
Vitamin E (VitE) from palm oil is usually separated from palm fatty acid distillate. VitE separation from crude palm oil (CPO) has been rarely reported. This work presents a separation of VitE from CPO in a bench scale process to attain a high concentration of VitE oil by methanol extraction, followed by fatty acid esterification and glycerides transesterification in the extract, and finally concentrated by high vacuum evaporation of fatty acid methyl esters. The starting content of VitE in CPO was 887 ppm, which was first extracted with an equal mass of methanol and evaporated to gain 4,515 ppm of VitE in the evaporated extract. The extract was esterified and transesterified to convert free fatty acids and glycerides into fatty acid methyl esters. The bulk of methyl ester was evaporated under high vacuum using Kugelrohr apparatus and the oil residue contained 69,950 ppm VitE, which was 80 times the original amount in CPO. By this development, 80 wt.% of VitE remains in the extracted CPO as a natural antioxidant and the CPO can be normally purified as edible palm oil or used as feed stock for biodiesel production.
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The Polarization and Depolarization Current Characteristics of Mineral Oil, Natural Ester (FR3), Palm Oil, and Liquid Impregnated Pressboard
(2019-06-01)
Siriworachanyadee, Jompatara
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Maneerot, Sakda
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Nimsanong, Phethai
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Kitchaiya, Prakob
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Pattanadech, Norasage
Polarization and Depolarization Current (PDC) measurement is a non-destructive dielectric testing method used to determine the electrical properties of transformer insulation. Nowadays, natural ester has been used as alternative liquid insulation in transformers because it can be easily decomposed, highly flammable, resistant to moisture, and prolong of pressboard (solid insulation in a transformer) compared with mineral oil. Furthermore, palm oil is also an interestingly alternative insulating liquid. This paper presents the PDC characteristics of mineral oil, natural ester (FR3), and palm oil under various temperatures. All received liquid specimen were dry in the controlled temperature oven at 70°C under 200 mbar and then they were cooled down to ambient temperature around 25-30°C. The liquid samples were investigated for three cases as follows: 1) moisture content measurement according to ASTM D1533, 2) dielectric dissipation factor measurement as per ASTM D924, and 3) polarization current and depolarization current measurement at liquid temperature of 30°C, 50°C, and 70°C respectively. The PDC characteristics of mineral oil impregnated pressboards and natural ester impregnated pressboards were also investigated. The PDC test results were analyzed. It was found that the dielectric response of mineral oil was significantly different from natural ester (FR3) and palm oil. Besides, it was clearly that the conduction current of liquid insulation increased with increasing liquid temperature. Moreover, the pressboard impregnated with natural ester provided better insulation characteristics such as lower conduction current than that of the pressboard impregnated with mineral oil.
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Concentrated lactic acid production from invert sugar in alkaline solution
(2019-01-01)
Sirisangsawang, Rinlada
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Kitchaiya, Prakob
High concentration of lactic acid production is not practical in industry, which is currently produced by fermentation. This work investigated lactic acid synthesis derived from invert sugar in an alkaline solution at low temperature under atmospheric pressure. 30 % invert sugar was continuously added into 3.5 - 8.5 M concentrated sodium hydroxide solutions in a semi-batch reactor at 30 – 80 °C. The central composited design (CCD) was used for design experiments and three variables such as reaction temperature, initial concentration of sodium hydroxide (NaOH) and feed time being investigated. The reaction temperature and initial concentration of NaOH were more pronounced on the yield. At 70 °C, 8.5 M NaOH, and feed time of 6 h. 76 % lactic acid yield was achieved. An independent study at 70 % invert sugar and 15 M NaOH solution caused runaway in a batch reactor, while the yield in a semi-batch reactor was 62 %.
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Effect of regeneration conditions on dehumidification desiccant packed bed
(2019-01-01)
Murathathunyaluk, Siripan
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Junjiewchai, Jarukit
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Kitchaiya, Prakob
In the present study, dynamic performance of a dehumidification desiccant regeneration system has been investigated theoretically. The simulation of the combined heat and mass transfer that occur in a solid desiccant packed bed is carried out with MATLAB. The presented model takes into account only forced convection along the bed without heat conduction and heat loss across the wall. The simulated results are validated with the previous published studies. Using the explicit finite differential numerical method, the performances of dehumidification systems are presented by moisture removal capacity (MRC). The dynamic systems have been studied at the regeneration temperatures between 60 to 120 °C and air flow ratio between 0.2 to 2. Increasing the regeneration temperature and the regeneration air flow ratio are shown to have positive effect to MRC. However, excessively increase these values leads to the constant of MRC. Therefore, optimum values for these manipulated parameters has been examined. The result of this study help reducing heat consumption for regenerating heated air; as well as, reducing electric consumption used by the fan.
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Modeling of Non-Isothermal Adsorption Process in a Silica Gel Desiccant Packed Bed
(2018-01-01)
Murathatunyaluk, Siripan
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Srichanvichit, Koranut
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Anantpinijwatna, Amata
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Kitchaiya, Prakob
This study investigated a numerical simulation of a column packed bed using silica gel. This bed is either stationary or steadily rotating, leading to different operation-regeneration schemes. Although models of these systems have already been developed and fitted with available data, they require large number of costly and time-consuming experiment to be applicable. Therefore, the development of a fundamental predictive mathematical model is necessary. The present model is a one-dimensional numerical solution of the conservation equations for heat, water vapor, and adsorbed water inside the silica gel desiccant under the constraint of local equilibrium between the two phases, which is characterized by fundamental sorption isotherms. The system of a non-isothermal adiabatic under constant pressure containing heat and mass transfer phenomena between vapor and solid phases are considered. The numerical results show good agreement with a maximum root of mean square of errors of 6.6% and 9.6% for exit air temperature and humidity, respectively
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Optimizing Decolorization Efficiency of Methylene Blue by Photo-Fenton Process over Fe-Diatomite using Central Composite Design
(2018-01-01)
Sriprom, Pongsert
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Champa, Varocha
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Kitchaiya, Prakob
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Assawasaengrat, Pornsawan
The methylene blue was degraded by photo-fenton over Fe-diatomite prepared by dry impregnation method. The characterizations of catalyst were studied by XRD, XRF and BET surface area. The photo-fenton reaction conditions were studied as parameters of the H<inf>2</inf>O<inf>2</inf> concentration, the amount of Fe-diatomite, the initial concentration of methylene blue and the initial pH of solution, which were designed by central composite design (CCD) based on response surface methodology (RSM) to accomplish the optimal condition. The results showed that the optimum condition was at the initial H<inf>2</inf>O<inf>2</inf> concentration of 116 mg/L, the Fe-diatomite of 1 g/L, the initial MB concentration of 200 mg/L and the pH of 5.8. It could predict the decolorization value of 100% and reduce the total organic carbon (TOC) to 72.3%. Finally, the validation was tested in 5 runs at the optimization about 99.2 ± 0.2% which implied that the regression model is in a good agreement.

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