Glycerin Purification Research Articles

Production Capacity Prediction and Optimization in the Glycerin Purification Process: A Simulation-Assisted Few-Shot Learning Approach

Chemical process control relies on a tightly controlled, narrow range of margins for critical variables, ensuring process stability and safeguarding equipment from potential accidents. The availability of historical process data is limited to a specific setpoint of operation. This challenge raises issues for process monitoring in predicting and adjusting to deviations outside of the range of operational parameters. Therefore, this paper proposes simulation-assisted deep transfer learning for predicting and optimizing the final purity and production capacity of the glycerin purification process. The proposed network is trained by the simulation domain to generate a base feature extractor, which is then fine-tuned using few-shot learning techniques on the target learner to extend the working domain of the model beyond historical practice. The result shows that the proposed model improved prediction performance by 24.22% in predicting water content and 79.72% in glycerin prediction over the conventional deep learning model. Additionally, the implementation of the proposed model identified production and product quality improvements for enhancing the glycerin purification process.

Charcoal adsorbents for glycerin purification

The article is devoted to the research of the chemical composition of coals. The main goal of the research is to choose the method of its enrichment. The authors established that after the enrichment of coal, the ash content sharply decreased due to the washing off of its inorganic part. The process of coal enrichment, at a ratio of 1:2 (coal: water) has a positive effect on reducing the ash content by 1.3 times. Based on the data obtained, it was found out that the enrichment process in the coal production adsorbents is necessary to reduce their ash content. Based on the research a technological scheme for obtaining a carbon adsorbent and solutions for their regeneration were proposed.

In English

In this work, we investigated granular activated carbons Norit 1240 (AC) – initial and spent (SAC) with adsorbed impurities after purification of technical glycerin and subsequent washing with water. The aim of the work was to establish the optimal conditions for the thermal regeneration of AC at the pyrolysis unit and to quantify the adsorbed impurities in the SAC using thermogravimetric analysis (TGA). For all AC samples, the specific surface area (S), adsorption activity on iodine and mass fraction of moisture were measured. It was established by the TGA method that water is released in the temperature range of 20 – 180 °C, and glycerin – 180 – 400 °C. Spent AC contains up to 31.3 wt. % H2O and up to 37.3 wt. % C3H5(OH)3. The pyrolysis reactor was used for the regeneration of SAC samples. It was shown that after the reactivation of SACs, their specific surface area is restored to 45-94% of the initial one. There is a weak correlation between S and iodine number, R=0.64. Adsorption activity for iodine and S increase in the same row ACspent > ACregenerated > ACinitial. As a result of regeneration, activated carbons suitable for reuse were obtained.

APPLICATION OF VIBRATION EFFECTS IN BIOFUEL PRODUCTION

The considered effective way of processing by-products of biofuel production. The increase in the productivity of the technological line is achieved through the introduction of new vibration equipment for the primary purification of raw glycerin. This study proposes a new approach to determine the efficient operation of a new machine, which is useful for the purification of glycerol based on the combinatorial process of centrifugation and vibration separation. The mathematical mechanical-rheological evaluations are developed based on the experimental results. Has been proposed to evaluate the rheological characteristics of raw glycerin purification based on the experimental testing. A compression device has been used to determine the value of the unilateral deformation of this material, which allows simulating a condition of a material at various technological modes of processing. In this study, the changes of material properties under centrifugation and vibration separation processes in a vibrocentric machine have been investigated. At a choice of optimum technological parameters of processing of food masses by means of vibration methods of rheology are widely applied. In particular, the interaction of the working body of the machine with the treated environment. In order to find the optimal parameters of the technological regime, the process was considered comprehensively from the standpoint of mechanics and rheology. The methods of mechanics describe the interaction of the working body with the treated environment as a mechanical object; rheology, in turn, allows you to reveal the internal processes in the environment. The system under study can be attributed to the elastic-viscous medium, which is described by a phenomenological model consisting of interconnected elastic and viscous elements.

Effect of vibration on the rheological properties of glycerin during its purification

In this paper, a new method using the experimental results is proposed to determine the rheological characteristics of glycerin purification by a vibrocentric machine. The experimental testings are reported based on the values of the unilateral deformation of the glycerin under different process modes. The Kelvin-Voight model is used for rheological modeling of the proposed vibrocentric purification of glycerin. A new compression device is presented for the experimental studies, which is useful to simulate different technological processing mods. The behavior of glycerin during the centrifugation and vibrationally separation could be simulated using the introduced compression device. Test results show that a 15 % increase in the deformation of the glycerin is achievable using the simultaneous vibration-based and centrifugation processes. The impacts of amplitude-frequency parameters of glycerin purification using the vibrocentric process on the stress, strain, and strain rate have been studies. The obtained test results illustrate that the specified rheological characteristics increase sharply due to the resonant mode of the vibrating machine’s operation.

Novel Approach of Biodiesel Production Waste Utilization to Support Circular Economy in Biodiesel Industry

Current development of industry nowadays is more towards sustainability and greener production that minimize the production of waste, for example the production of biodiesel energy from Refined, Bleached, and Deodorized Palm Oil (RBDPO). However, biodiesel production is still could not eliminate the hazardous waste that is glycerin pitch. Glycerin pitch is a waste found in the glycerin purification unit which is a unit used to produce the high-grade glycerin, a side product of biodiesel production. Up until now, the existing glycerin pitch is still not well managed and remains as a hazardous waste. Glycerin pitch contains a sodium salt that can be recovered to produce biodiesel transesterification catalyst, sodium methoxide. Applying a concept of circular economy, a catalyst recovery building block is attached to integrated biodiesel process with glycerol purification. The process consists of three units, solid-liquid extraction to separate inorganic salt contains in the pitch, Chlor-Alkali process to convert inorganic sodium salt to sodium hydroxide, and catalyst making reactor to produce a sodium methoxide. Using a simulation process, the amount of catalyst recovered in the process is 43.78%.

In Russian

In this work, we investigated granular and powder activated carbons (AC) – initial and waste with adsorbed impurities after purification of technical glycerin and subsequent washing with water. The aim of this work was to quantify the adsorbed impurities in the spent AC using thermal analysis (TA) and to work out the conditions for thermal regeneration of AC. TA of AC samples was carried out in an atmosphere of helium and air; the specific surface area of AC was measured by the method of low-temperature desorption of argon (SAr). It was established by the TA method that water is released in the temperature range of 20 – 170 °C, and glycerin – 170 – 400 °C. Spent AC contains up to 22.8 wt. % H2O and up to 44.6 wt. % C3H5(OH)3. Based on these data, it was proposed to regenerate spent coal by heating at 400 °C in air. In the case of a granular AC sample, the regeneration proceeds completely, while for a powder AC sample, the specific surface area with respect to argon is restored only by 22 %, from the initial 2170 m2/g. The adsorption isotherms of methylene blue (MB) of the initial samples are located higher than for the spent ones, since in the spent ones part of the surface is occupied by adsorbed glycerin. The SMB values calculated from the adsorption of methylene blue in the spent AC samples are strongly overestimated in comparison with SAr. Probably, MB displaces glycerin from the surface or interacts with it to form complexes.

Transient Response of Glycerin Heating Process

Controlling the temperature of the glycerin purification process system was not an easy task, as an increase in operating temperature would significantly reduce the quality of the purified glycerin. This is because an unlimited increase in temperature beyond the set point and an excessive prolongation of the heating process would result in the formation of an excessive secondary oxidation product in the final purified glycerin. This paper discusses the transient response characteristics of the glycerin heating process using a parallel PID controller. The glycerin heating process behavior was determined experimentally using step input test and modelled as the First Order plus Delay Time. The controller parameters wereadjusted using Ziegler-Nichols, Cohen-Coon and Wang tuning methods, each of which was analyzed on the basis of the corresponding integral error criterion value. The Integral Square Error, Integral Absolute Error and Integral Time-weighted Absolute Error criteria value were used to evaluate the efficiency of the glycerin heating process. The transient response performances in terms of overshoot, rise time and settling time were also evaluated. Simulation work has shown that the process has experienced high overshoots for Ziegler-Nichols and Cohen-Coon, and has taken longer time to settle. Wang method exhibits with no overshoot but slow response. The lower gain PID controller was found to improve the process response in terms of overshoot but increase in the rise time and settling time. The results indicate that the desired process performance were more or less influenced by the interaction between the tuning parameters. The Ziegler-Nichols PID controller is not recommended for controlling glycerin heating process due to process response oscillations that are difficult to eliminate without prolonging the heating cycle.

Glycerin Purification Process Plant System Design and Performance

Pure glycerin is normally adopted for the production of cosmetics, personal care and food industryin order to produce quality end-products. Most crude glycerin, however, contains a sticky substance and coloring materials that may affect the flavor and color of the end-product. This paper presents the design and development of the glycerin purification process plant system to purify the crude glycerin through heating process. The process system is designed and developed based on the information gathered from literature. The system architecture of the process plant is developed using industrial instrumentations and hardware system found in the laboratory. The choice of transducer and final control element used is based on the needs of the developed system. Glycerin purification is a process of removing the peroxides and the secondary products found in the crude in which the process is significantly depends on the operating temperature. In this work, the temperature control system for glycerin heating process is designed and the process controllability in terms of settling time and percent overshoot is experimented using PID controller. The results of the experiments show that the developed glycerin purification process plant system is workable and able to provide good temperature control system performance for glycerin heating process. PID controller with correct controller parameters adjustment can improve the glycerin heating process system performance. The main contribution of this paper is the development of the glycerin purification process plant system in which the system implemented is different from any of the related publications in the aspects of instrumentation and hardware system used.

Flux Decline and Blocking Mechanism in Ultrafiltration of Glycerin-Rich Solution

In the oleochemical industry, crude glycerin is a byproduct of biodiesel production. As a byproduct, crude glycerin has a low economic value and very limited applications. To improve these limitations, the purification of glycerin is required. One method for glycerin purification is a filtration process that uses ultrafiltration (UF) membranes based on polyethersulfone (PES). However, this process has several problems, particularly the flux decline that occurs during filtration. Thus, the aim of this study was to obtain a better understanding of the flux decline and blocking mechanism that occur in the UF of glycerin. In this work, the flux decline and blocking mechanism were observed by commercializing the UF of the PES membrane with a 1-kDa molecular weight cut-off. The investigated parameters were the pressure, temperature, and pH with ranges of 2–4 bar, 40–60oC, and 4–9, respectively. The results showed that the flux decline was significant due to the relatively small size of impurities, which clog the membrane’s pores. Furthermore, the blocking mechanism was analyzed using Hermia’s model, and it was found that the blocking mechanism was mostly dominated by cake formation, except at a pH of 7.

Purification and characterization of glycerin obtained from soybean biodiesel production

The crude glycerin is a raw material which can be applied in a wide range of products, even with all its impurities, without the need for purification. However, the purification processes allow a wider application, making it more salable. With increasing demand for biodiesel, a glycerin excess is being released to the market. Therefore, the search for alternative treatments for the glycerin derived from the biodiesel production process is of utmost importance, ensuring biofuel production flow. This paper presents glycerin purification experiments done in a crude glycerin (64.44% of glycerol) obtained from the soybean biodiesel production, which was subjected to pre-purification process, purification with activated carbon and by ion exchange process. After the purification process the glycerin sample was characterized and compared with commercially used glycerin. The highest content of glycerol achieved was 94.22% corresponding to the steps of: pre-purification process (washing, acidification, separation, neutralization, salting-outing and evaporation); purification with activated carbon and by ion exchange process with mixed resin.

Experimental Investigation and Thermodynamic Modeling of Glycerin/Methanol/Organic Solvent Systems

AbstractGlycerin is an important by‐product in biodiesel production. To increase its quality to be suitable for use it in other operations, e.g., the pharmaceutical industry, it needs to be purified. Therefore, the purification of glycerin by liquid‐liquid extraction of methanol using different solvents was investigated. It was shown that, in terms of separation, petroleum ether was more effective than toluene and toluene was more effective than n‐butanol. In addition to the experimental investigations, the NRTL and UNIQUAC thermodynamic models were used to predict the compositions of ternary mixtures of glycerin + methanol + organic solvent in glycerin‐rich and organic solvent‐rich phases. The results showed the high accuracy of the presented models and their consistency with the measured data.

A new approach for salts removal from crude glycerin coming from industrial biodiesel production unit

The aim of the present work is to propose purification and cleaning of the residual salt from the crude glycerin purification step from distillation, using relatively simple physicochemical processes and easy industrial implementation. For this purpose, Total Organic Carbon (TOC), chloride content, metal analysis (Na, K, Ca and Mg), glycerol content, moisture content, total solids and ash content were employed to characterize the crude sample. The crude sample was extracted using different solvents (methanol, ethanol, chloroform, and dichloromethane), where methanol proved to be the most efficient solvent for extracting the organic phase of the sample under study. It was evaluated the ratio of residual salt:solvent (1:3, 1:5 and 1:10) which afforded the highest extraction efficiency as well as the required reaction time for the same (1, 5, 10 and 15 min). After obtaining the treated sample, it was subjected to the same characterization analyzes of the crude sample, for comparison. Results indicate that both the yield and quality of the recovered salt are governed not by the time of contact, but by the residual salt:solvent ratio. A significant reduction in total organic carbon (TOC) was observed between crude and treated samples, which was accompanied by an expressive increase in salt content, mainly for chloride and sodium ions. From a social and economic point of view, the purification of sodium chloride salts allows the use of a residue with potential application as a mineral salt.

Glycerin purification using asymmetric nano-structured ceramic membranes from production of waste fish oil biodiesel

Biodiesel is an environmental friendly alternative liquid transportation fuel that can be used in diesel engines without major modifications. The scope of this research work is to produce biodiesel from waste fish oil and its purification from the byproducts using a ceramic membrane. Transesterification of waste fish oil was applied for the biodiesel production using methanol in the presence of KOH as a catalyst. Effect of catalyst weight percent, temperature and methanol to oil molar ratio (MR) on the biodiesel yield have been studied and the results show that highest methyl ester yield of 79.2% has been obtained at 60 °C, MR: 6 and 1% KOH. The produced biodiesel purified by a ceramic membrane. Membrane flux and glycerin removal at different operating conditions such as temperature, trans-membrane pressures and cross flow velocities have been measured. Glycerin purity by membrane method is 99.97% by weight at the optimum condition. The highest membrane flux occurred at 50 °C temperature, 1 bar pressure and 3 m/s velocity.

Recent trends in biodiesel production

This article fully discusses the recent trends in the production of one the most attractive types of biofuels, i.e., biodiesel.with a focus on the existing obstacles for its large scale production. Moreover, recent innovations/improvements under three categories of upstream, mainstream, and downstream processes are also presented. Upstream strategies are mainly focused on seeking more sustainable oil feedstocks and/or enhancing the quality of waste-oriented ones. The mainstream strategies section highlights the numerous attempts made to enhance agitation efficiency including chemical and/or mechanical strategies. Finally, the innovative downstream strategies basically dealing with 1) separation of biodiesel and glycerin, 2) purification of biodiesel and glycerin, and 3) improving the characteristics of the produced fuel, are comprehensively reviewed.

Purification of glycerol from biodiesel production by sequential extraction monitored by 1H NMR

The purification of raw glycerin in biodiesel production can provide economic benefits and help to avoid residue accumulation, thus reducing environmental impacts. In this work, the glycerin obtained from biodiesel production by catalytic transesterification of waste cooking oil was purified by sequential extraction with organic solvents, followed by discoloration with activated coal and monitoring by 1H NMR spectroscopy. Through sequential extraction with petroleum ether and toluene, in that order, followed by discoloration with activated carbon, 99.2% pure glycerin was obtained. This technique is shown to allow for glycerin purification using less drastic or hazardous conditions than those commonly applied in vacuum distillation.

Dehydration of glycerin solution using pervaporation: HybSi and polydimethylsiloxane membranes

The dehydration of glycerin solution is an important step in glycerin purification process. In present work, pervaporative dehydration of glycerin solution was studied using HybSi and polydimethylsiloxane (PDMS) pervaporation membranes. The effects of physical property of membrane, operating parameters and glycerin concentrations on the membrane permeate flux and selectivity were examined. The present studies showed that hydrophilic HybSi membrane could provide higher permeate flux as compared to hydrophobic PDMS membrane under an identical operating condition. Remarkable difference in permeate flux was observed when the process was operating at room temperature. The influence of crossflow rate on the permeate flux was relatively low as compared to operating pressure and temperature. Operating temperature was found to possess the greatest influence on permeate flux and selectivity. The speculated molecule movement during pervaporation was discussed based on boundary layer theory and hydrogen bonding theory. The final permeate flux and permeance water content of 13.63kg/m2h and 98wt%, respectively, were achieved by HybSi membrane in the dehydration process of 90wt% glycerin solution into 99wt% glycerin solution over a period of ~90min.

Biodiesel production from non-degummed vegetable oils: Phosphorus balance throughout the process

In this work, the biodiesel production process using high-phosphorous content raw materials is studied. The objective is to determine the phosphorous mass balances, in order to determine the amount of this element in each stream of an integrated process including esterification, transesterification, and glycerin purification. It was found that up to 97% of the initial phosphorous content in the oil is accumulated in the glycerin phase. The small amount of phosphorous left in the biodiesel phase after decantation is eliminated during the acid extraction carried out to purify the biodiesel. The evaporation of methanol after the reaction plays a major role in the quantity of phosphorous and soaps left in the biodiesel phase. For example, with a crude soybean oil containing 226ppm of phosphorous, the methanol content at the end of the reaction in the biodiesel phase is 4.6wt.%, being the phosphorous content 7.1ppm, and the soap concentration 3.89g/kg. The methanol was evaporated in such a way that its concentration dropped to 0.35wt.%, and the phosphorous and soaps concentrations decreased to 4ppm and 0.7g/kg respectively. This has a direct impact in the quality of the final biodiesel. During the esterification, also an important amount of phosphorous is eliminated from the biodiesel phase.

Refinación de la Fase Glicerina del Biodiesel de Aceite de Palma empleando Ácidos Minerales

A method is proposed for the purification of glycerin from palm oil biodiesel production to achieve the required standards, for use in applications non-requiring USP grade (United States Pharmacopoeia), particularly those defined by Colombian standards. A factorial design 2 3 was used with the three variables: type of acid (phosphoric or sulfuric acid), quantity of methanol and pH. It was found that the treatment with sulfuric acid, 50% methanol and pH of 6 gave the best results, and requires an activated carbon bleaching to meet the required color. Refined and bleached glycerin obtained meets the requirements of glycerin type 2 grades 1 and 2 according to the Colombian standard NTC1274.

A perspective on incorporation of glycerin purification process in biodiesel plants using waste cooking oil as feedstock

Abstract In biodiesel production through transesterification, glycerin is produced as a valuable co-product. Some biodiesel plants have incorporated a glycerin purification process since the beginning of operations. The objective of this study is to evaluate the benefits of the incorporation of a glycerin purification process to a biodiesel plant where has already been constructed without the initial consideration of including an extra process for glycerin. A cost–benefit analysis is applied to evaluate the potential benefit from the incorporation of this process, in cases of a high plant cost and a low plant cost, with and without a glycerin facility installation. Our results show that the installation of a glycerin purification process could benefit a biodiesel plant through glycerin recovery and a decrease in wastewater treatment cost. The current downward trend in the market price of glycerin could be offset by encouraging the development of new applications for glycerin in order to expand the existing market and to stabilize the market price. However, biodiesel plants using waste cooking oil in Japan still need government subsidy to sustain their business activity.