Development of a spiral finned crystallizer for progressive freeze concentration process

Progressive freeze concentration (PFC) has emerged as a viable technology for concentration of liquid solution. For this present research, a new spiral finned crystallizer was designed and fabricated as the main component in the PFC system. The spiral finned crystallizer was designed with the aim of increasing productivity and quality of product. Further analysis on its performance, a process optimization and modelling study were carried out after the completion of the design. For the performance analysis, glucose solution was used as a liquid food model solution. The performance of the crystallizer was analysed through the system efficiency assessed in parallel with the effect of operating conditions. It was found that the effective partition constant (K) was satisfactorily low at intermediate coolant temperature, high circulation flowrate, intermediate circulation time and intermediate shaking speed. A low K value and a high solute recovery (Y) value represent the best performance of the PFC system. In terms of Y, the highest achieved was approximately 0.98 g of glucose obtained per 1 g of initial glucose. A mass validation was successfully obtained from the experimental results. The evaluation of the crystallizer in terms of ice production, fluid mechanic and heat transfer characteristics was also carried out. 0.64 g/m2s1 of maximal ice production was attained, reflecting a good function of the spiral fin. A process optimization employing Response Surface Methodology (RSM) in Statistica software was applied to study the relationships of coolant temperature, circulation flowrate, circulation time and shaking speed on K and Y. The optimum conditions to produce the best K and Y were found to be 10.30 °C of coolant temperature, 3097.50 mL/min of circulation flowrate, 64 minutes of circulation time and 29.53 ohm of shaking speed. The best K predicted was 0.25 and 0.99 for Y. A heat transfer model was also successfully developed in order to study ice crystal mass formation

Nucleation

Nucleation is one of the processes that involves at the beginning of the certain process like freezing, melting, boiling, condensation and crystallization. This process normally occurs in the industry, where it is involving the thermodynamic phase that involves work, energy and temperature. The nuclei growth happens when the initial phase changes to the other phase. Unfortunately, the detail for the theory of nucleation is not well-known around the people who are working in the industry, even though there are many reports or writings available. Thus, few types of nucleation like homogeneous and heterogeneous nucleation and the other theory of nucleation have been summarized in this chapter

Methods for Enhancing Recovery of Heavy Crude Oil

The methods of enhancing recovery of heavy crude oil explore the importance of enhanced oil recovery and how it has grown in recent years due to the increased needs to locate unconventional resources such as heavy oil, shale, and bitumen. Unfortunately, petroleum engineers and managers are not always well-versed in the enhancement methods available when needed or the most economically viable solution to maximize their reservoir’s productivity. Various recovery methods have been explored to extract heavy oil from deep reservoirs or oil spills. This chapter summarizes the details of methods, namely nanoparticle technology, carbon dioxide injection, thermal recovery and chemical injection, which include the methodology as well as the findings

Solvent-Aided crystallization for biodiesel purification

The application of solvent-aided crystallization (SAC) is based on the addition ofa solvent, here 1-butanol, to crude biodiesel to catalyze the purification process byseparating biodiesel from contaminants via crystallization process. Response sur-face methodology was applied to optimize the process parameters of SAC, repre-sented by biodiesel purity.Peer ReviewedPostprint (updated version

Microwave-assisted Hydrothermal Carbonization for Solid Biofuel Application : A Brief Review

Acknowledgment The authors would like to acknowledge Institute of Sustainable En- ergy of University Tenaga Nasional for supporting and funding the work through the AAIBE Chair of Renewable Energy research fund-Grant no: 201901KETTHA.Peer reviewedPublisher PD

Vacuum-assisted block freeze concentration studies in cheese whey and its potential in lactose recovery

Block freeze concentration (BFC) is considered an emerging technology which allows the acquiring of high quality organoleptic products, due to the low temperatures employed. In this study we have outlined how the vacuum-assisted BFC of whey was investigated. The effects of vacuum time, vacuum pressure, and the initial solids concentration in whey were studied. The results obtained show that the three variables significantly affect each of the following parameters analysed: solute yield (Y) and concentration index (CI). The best Y results were obtained at a pressure of 10 kPa, 7.5°Bx, and 60 min. For CI parameter, the highest values were given at 10 kPa, 7.5°Bx, and 20 min, respectively. In a second phase, by applying the conditions that provide higher solute yield to three different types of dairy whey, Y values of 70% or higher are reached in a single step, while that the CI of lactose are higher than those of soluble solids. Therefore, it is possible to recover, in a single step, at least 70% of the lactose contained in the initial whey samples. This suggests that vacuum-assisted BFC technology may be an interesting alternative for the recovery of lactose contained in whey.This research received no external funding. The APC was financed by AGRUPS-2022 at Universitat Politècnica de Catalunya (UPC) and SGR-Cat 2021 of Departament de Recerca i Univer- sitats (Generalitat de Catalunya)Objectius de Desenvolupament Sostenible::12 - Producció i Consum ResponsablesPostprint (published version

A review on recent progress in membrane distillation crystallization

Membrane distillation crystallization (MDC) is a promising hybrid separation technology that can play an important role in desalination, mineral recovery from liquid solution as well as in carbon dioxide fixation. MDC combines membrane distillation and crystallizer into one integrated unit that allows excellent recovery of clean water and high purity salt from highly concentrated salts solution (i.e., brine), which is otherwise detrimental when discharged to the environment. The process intensification addresses the limitation of standalone membrane distillation and a standalone crystallizer (i.e., temperature and concentration polarization, membrane properties) when operated as individual technology. This review discusses the fundamental of MDC focused on how the process intensification addresses those standalone units' limitations. Later, MDC's potential applications in addressing some pressing issues such as water scarcity and climate change are also evaluated. Lastly, current trends in the MDC research are discussed to project the required future developments.Postprint (updated version

Energy efficient harvesting of Spirulina sp. from the growth medium using a tilted panel membrane filtration

Membrane fouling is one of the main drawbacks in membrane-based microalgae harvesting. This study assessed the tilted panel to enhance filtration performance of Spirulina sp. broth. The influences of the operating parameters including the tilting angle, aeration rate and membrane materials on filtration performance and energy consumption were evaluated. Results showed that the system was effective and energy-efficient for membrane fouling control. The permeability peaked at a tilting of 45◦ thanks to combination of aeration and panel tilting. The microfiltration performed better than the ultrafiltration membrane due to the effective impact of air bubbles for foulant scouring that maximized the membrane intrinsic property. Small aeration rate of 1.0 L/min offered a high plateau permeability of 540 L/(m2⋅hr⋅bar) in which reversible fouling almost fully absent. The high permeability could be achieved under a low energy input of 0.2 kWh/m3

Biodiesel Purification via Ultrasonic-Assisted Solvent-Aided Crystallization

Wet washing is a widely used method for biodiesel purification. However, this technique generates a large amount of wastewater that needs to be treated afterward, which is costly and time-consuming. Thus, solvent-aided crystallization (SAC) with ultrasonic irradiation as solution movement assistance was introduced. This technique is based on the addition of 1-butanol to biodiesel to enhance purification via crystallization. During crystallization, two phases are formed, where glycerol solidifies (solid phase) and pure biodiesel remains (liquid phase). Technically, the implementation of ultrasonic technology can optimize laboratory work by saving time, as no cleaning or washing of the propeller is needed. Biodiesel purity was analyzed using gas chromatography-mass spectroscopy (GC-MS), where a purity of 99% was achieved. The optimum parameters in achieving higher purity fatty acid methyl ester (FAME) were a 1-butanol concentration of 1 wt.%, a coolant temperature of 9 °C, and a crystallization time of 40 min

Saponin Stabilization via Progressive Freeze Concentration and Sterilization Treatment

Saponin is a biopesticide used to suppress the growth of the golden apple snail population. This study aims to determine the stabilized conditions for saponin storage. The maceration process was used for saponin extraction, and for saponin concentration, progressive freeze concentration (PFC) was used. Afterwards, stability analysis was performed by storing the sample for 21 days in two conditions: Room temperature (26 °C) and cold room (10 °C). The samples kept in a cold room were sterilized samples that undergo thermal treatment by placing the sample in the water bath. The non-sterilized samples were kept in room temperature condition for 21 days. The results showed that saponin stored in the cold room (sterilized sample) has low degradation with higher concentration than those stored at room temperature in stability analysis with the highest saponin concentration (0.730 mg/mL) at a concentration temperature of −6 °C and concentration time of 15 min. The lowest saponin concentration obtained by saponin stored at room temperature (non-sterilized sample) is 0.025 mg/mL at a concentration temperature of −6 °C and concentration time of 10 min. Thus, the finding concluded that saponin is sensitive to temperature. Hence, the best storage condition to store saponin after thermal treatment is to keep it in a cold room at 10 °C