Extraction Tower Research Articles

Experimental, numerical simulation and genetic algorithm as a hybrid method for the design of hydrogen peroxide separation via non-dispersive solvent extraction

This work employed a hybrid approach combining experiments, numerical simulation, and genetic algorithm (GA) to optimize the non-dispersive solvent extraction (NDSX) process of H2O2. A numerical simulation model with high accuracy was developed. The relative error between the simulation results and experimental data was controlled within 2.2 %. The results indicated the velocity of lumen side and temperature are the key factors affecting the extraction efficiency. The non-dominated sorting GA-II algorithm coupled with the numerical simulation was used to optimize the NDSX process. The Pareto optimal design of the NDSX process can be achieved within the water outlet concentration range of 13.44 to 550.2 kg m-3. Intensification factors of NDSX versus extraction towers are evaluated to be 17.9 and 13.2. In summary, this work provides a design framework for NDSX of H2O2, which is expected to simultaneously promote the mass transfer efficiency and safety of the H2O2 separation process.

Optimization of extraction tower structure and extraction conditions for lincomycin separation

Lincomycin is a widely used aminoglycoside antibiotic. For its separation from fermentation broth in production, solvent extraction is usually applied because of its low cost and high capacity compared to other bioseparation methods. The multistage mixer-settler is a common extraction equipment in commercial production, but it occupies a large area and causes pollution. In this study, a fully enclosed turbine tower was designed and applied in order to replace the mixer-settler. Its structure parameters (turbine diameter, tray porosity) were optimized on the basis of the extraction effect of lincomycin. The results showed that with 35% tray porosity and 28/26 mm turbine diameter of the tower, the extraction rate was kept above 99.0% steadily under 375 rpm/min rotating speed and 60 °C temperature. The extraction effect is much better than mixer-settler and such turbine tower is expected to be applied in the commercial production of lincomycin.

Experimental study of the flow structure in packed tray-type column extractors

Liquid extraction is a well-known separation process that has been widely used in the chemical industry for many years, for example, in the selective purification of oil fractions, in the purification of liquefied gases from hydrogen sulfide, in the production of petrochemicals, in the recovery of metals, in nuclear fusion, in food and pharmaceutical industry. On-going elaborations aimed at engineering solution search in order to improve mass-transfer processes are in progress on a permanent basis. Combination of trays and packing in the fractionator results in stream disequilibrium which leads to worse hydrodynamic conditions in the splitter (extraction, rectifier tower and etc.) and causes significant difficulties in stable operating process maintaining. The study objective is to review the structure of stream structures in the extraction tower via examples of trays and packing combinations since the mentioned contact devices are widely used in industry but they are conventionally applied as individual contact devices and not in combination. Combination of the above contact devices may earn a supplementary synergetic effect. In the course of the experiment it was found out and described in graphic format that stream disequilibrium could be eliminated and hydrodynamic conditions in the extraction tower could be improved via extra stream supply in the tower shell. Research will be useful for the development of new designs of column equipment, for example, extraction. In order to expand the experiment in various hydrodynamic modes, it is proposed to simulate the experiment using, for example, the Solid Works 2020 software package and, in particular, one of its add-ons - Flow Simulation.

Theoretic and experimental research on the possibilities for moderning and reabilitating the extraction installation of the Slănic Prahova salt mine

The paper deals with the subject of rehabilitation and mechanical modernization of the extraction plant within the mining operation of the salt mine from Slanic Prahova region. The extraction plant serves the 23 August mine shaft of the Unirea mine, and also this mine has been converted into a tourist mine. The rehabilitation of the extraction installation consists in the change of the cutting wheels from the extraction tower due to excessive degradation, requiring the redesign under strict conditions, and also the rehabilitation and extension of the saline water extraction system from the tourist mine. The modernization of the extraction plant consists in the change of the DC hoist engine with an asynchronous engine of the same energy power and research on the possibilities of increasing the cable transport capacity with technical changes made to the extraction tower, mine shaft and the sump. Modernization and rehabilitation carried out on the extraction installation at the Slanic Prahova salt mine, will provide a safety in operation and efficiency to using the necessary electricity for hoist engine operations.

Identification of the microbiota in sugar extraction juices by sequencing-based techniques

The importance of microorganisms in the beet sugar industry came up in 1930. Since then, several approaches have been made to describe these bacteria. For this purpose, mainly cultivation-based methods were applied. However, the majority of the microorganisms cannot be cultivated or are in the viable-but-non-culturable state. In addition, these methods are time-consuming and costly. Progress in molecular biology allows a cheaper, faster and more precise identification of the microbiota. This study evaluates the application of an 16S rDNA-based metagenomic sequencing approach based on Illumina MiSeq technology to identify the microbiota in raw juice and juice of mid-tower in a beet sugar production plant and compares the results with those obtained by cultivation-based techniques. All bacteria orders detected with cultivation-based methods could be also found with the applied metagenomic approach. In raw juice, mainly mesophilic bacteria such as Lactobacillus spp. and Leuconostoc spp. species were identified. Additionally, a partly large proportion of gram-negative bacteria belonging to the order Enterobacterales were detected by the metagenomic approach. The diversity in juice of mid-tower was much lower and predominated by mainly thermophilic genera such as Geobacillus, Caldanaerobius and Thermoanaerobacter. The last two mentioned genera belong to the class of Clostridia. Surprisingly, in the juice of mid-tower Lactobacillus species could be verified by cultivation-based methods as well as by the metagenomic approach. As a consequence, it can be presumed that lactobacilli can survive in this very specific environment at 70 °C occurring in the central part of the extraction tower.

Simulation of an Industrial-Scale Reactive Liquid–Liquid Extraction Tower Using Polar PC-SAFT Toward Understanding and Improving the Hydrolysis of Triglycerides

A comprehensive model for simulation and optimization of industrial-scale splitting towers that is able to predict the yield for the hydrolysis of bio-based triglyceride feedstocks is presented in this work. This model includes a variable glycerol equilibrium ratio, which is a function of the composition and temperature and is calculated using the polar version of the perturbed chain statistical association fluid theory (PC-SAFT), the autocatalytic effect of fatty acids in hydrolysis, and isomerization of poly-unsaturated fatty acids. Model validation is performed using process data from three real-life splitting towers covering four feedstock types, i.e., tallow, rapeseed oil, palm oil, and palm fatty acid distillate. Due to the composition gradients of the organic phase throughout the tower, it is crucial to properly account for the changes in the glycerol equilibrium ratio. The importance of feedstock flow rate, water/oil ratio, and temperature profile throughout the tower is analyzed and confirmed by sensitivity analysis. Our results show that modifying the temperature profile may shift the reaction equilibrium toward the fatty acid product. This knowledge is crucial for improving the energy and resource efficiency of fatty acid production, thereby improving its economic and environmental sustainability.

Automotive Waste Heat Recovery after Engine Shutoff in Parking Lots

<div class="section abstract"><span class="label">1</span><div class="htmlview paragraph">The efficiency of internal combustion engines remains a research challenge given the mechanical friction and thermodynamic losses. Although incremental engine design changes continue to emerge, the harvesting of waste heat represents an immediate opportunity to address improved energy utilization. An external mobile thermal recovery system for gasoline and diesel engines is proposed for use in parking lots based on phase change material cartridges. Heat is extracted via a retrofitted conduction plate beneath the engine block after engine shutoff. An autonomous robot attaches the cartridge to the plate and transfers the heat from the block to the Phase Change Material (PCM) and returns later to retrieve the packet. These reusable cartridges are then driven to a Heat Extraction and Recycling Tower (HEART) facility where a heat exchanger harvests the thermal energy stored in the cartridges. A series of mathematical models are created to estimate the recoverable heat from a standard parking lot configuration. A representative case study that considered 500 cars with periodic traffic flow over a period of 16 hours can heat approximately 25 kiloliters of potable water from 15°C to 50°C. Future development will involve the creation of strategies to extract heat during engine idling at traffic stops and drive through lanes.</div></div>

Improving particle flow in liquid-solid countercurrent extraction tower by insert structure optimization: A combined study on experiments and DEM simulations

The particle velocity distributions in the liquid-solid countercurrent nylon 6 extraction tower equipped with different types of inserts were investigated by both cold-model experiments and 2D-DEM simulations. The cold-model experiment results near the insert were well interpreted by the distribution of the particle contact force acquired from the DEM simulation. Compared with the disordered particle flow caused by a conventional single-funnel insert, the uniform particle flow could be realized by a special combination of single-funnel inserts with 53° and 35° dip angles of the upper and lower parts, respectively. In addition, a new type of insert, the multi-funnel insert, was found to be more beneficial in improving the uniformity of the particle velocity distribution because it made the particle contact force near the insert uniform. Furthermore, the mass flow state could be maintained in a wider range of discharge rate, which implied an enhancement of the operating flexibility of the tower equipped with the multi-funnel insert. These developed inserts have the potential to be applied in large-scale liquid-solid countercurrent extraction processes.

Experimental and simulation study of nylon 6 solid–liquid extraction process

Abstract The solid–liquid extraction process of nylon 6 to eliminate small molecules, i.e., caprolactam (CL), cyclic dimers (CD) and cyclic trimers (CT), is investigated in detail by both batch extraction experiments and numerical simulations. In the batch extraction experiments, due to the small molecules attaching to the polymeric surface, the basic physical mechanism shifts from surface diffusion to internal diffusion as the extraction proceeded. The experimental data are well reproduced by a diffusion model consisting of two distinct steps, characterized as surface diffusion and internal diffusion. Furthermore, based on the established mass transfer mechanism and diffusion model of the two distinct steps, the equilibrium constants and internal diffusion coefficients of CL, CD and CT are acquired. An industrial countercurrent extraction tower is further simulated. It is found that the extraction efficiency of CL can be significantly improved by increasing the temperature at the bottom portion of the tower. The elimination of CD, which can be greatly promoted by a high-concentration CL-water solution, is controlled by mass transfer resistance, whereas the removal of CL is mainly affected by the equilibrium.

Variations in toxicity of semi-coking wastewater treatment processes and their toxicity prediction

Chemical analyses and bioassays using Vibrio fischeri and Daphnia magna were conducted to evaluate comprehensively the variation of biotoxicity caused by contaminants in wastewater from a semi-coking wastewater treatment plant (WWTP). Pretreatment units (including an oil-water separator, a phenols extraction tower, an ammonia stripping tower, and a regulation tank) followed by treatment units (including anaerobic–oxic treatment units, coagulation-sedimentation treatment units, and an active carbon adsorption column) were employed in the semi-coking WWTP. Five benzenes, 11 phenols, and five polycyclic aromatic hydrocarbons (PAHs) were investigated as the dominant contaminants in semi-coking wastewater. Because of residual extractant, the phenols extraction process increased acute toxicity to V. fischeri and immobilization and lethal toxicity to D. magna. The acute toxicity of pretreated wastewater to V. fischeri was still higher than that of raw semi-coking wastewater, even though 90.0% of benzenes, 94.8% of phenols, and 81.0% of PAHs were removed. After wastewater pretreatment, phenols and PAHs were mainly removed by anaerobic-oxic and coagulation-sedimentation treatment processes respectively, and a subsequent active carbon adsorption process further reduced the concentrations of all target chemicals to below detection limits. An effective biotoxicity reduction was found during the coagulation-sedimentation and active carbon adsorption treatment processes. The concentration addition model can be applied for toxicity prediction of wastewater from the semi-coking WWTP. The deviation between the measured and predicted toxicity results may result from the effects of compounds not detectable by instrumental analyses, the synergistic effect of detected contaminants, or possible transformation products.

A Feasible Strategy for Calculating the Required Mass Transfer Height of a New Bubbling Organic Liquid Membrane Extraction Tower Directly Based upon the Experimental Kinetic Data

Extraction and recovery of gold(I) with extremely low concentration in cyanide wastewater were conducted as an example aimed to develop a feasible method based upon the experimental kinetic data for calculating the required mass transfer height of a new bubbling organic liquid membrane extraction tower. The kinetic extraction equation based on curve fitting the experimental c(t) ∼ t data from single column extraction could be established to describe the quantitative relationship of the concentration change of gold(I) in flowing-out aqueous solution from the tower with the reaction time in the tower, so that the required tower height involved in the axial gas mixing effect could be calculated from the residence time of the aqueous solution passing through the tower to achieve a target equilibrating concentration. The influence of organic phase recycling on the calculation was discussed. Double column extraction experiments confirmed that the suggested calculation method obtained from single column extraction is reasonable. The present work is in favor of understanding the mass transferring kinetic behaviors of target components in that suggested bubbling extraction tower, and it highlights a feasible strategy directly from the experimental kinetic data to calculate the required mass transferring height of the tower for its structure design, optimization, and scale-up, and provides fundamental data for future industrial application of the tower to extract and recover other heavy metal ions from wastewater.

A new bubbling extraction tower: Toward liquid–liquid solvent extraction at large aqueous‐to‐oil phase ratios

Enrichment and recovery of valuable components in industrial waste waters by traditional liquid–liquid solvent extraction is not economic due to extremely low concentrations of those targets. Large‐phase‐ratio extraction exhibits potential advantages for recovery of small quantities of target components from large volume of aqueous solutions. A novel bubbling extraction tower is proposed toward performing solvent extraction at large aqueous‐to‐oil phase ratios in this work. Organic extractants were covered onto surface of gas bubbles to form a layer of organic liquid membrane and the dispersed organic phase in tower could be small enough. The target components are extracted from aqueous feed solution onto the surface of the bubbles, and the enrichment ratios could be extremely high. We develop a feasible methodology to calculate tower height and operation phase ratios of the bubbling extraction tower, which is essential for future industrial scale‐up. Experimental results in pilot test are highly consistent with calculations. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3889–3897, 2015

Simulation of Citronellal Extraction Tower Based on Aspen Plus Software

Aspen Plus is a simulation system of large-scale generalized flowsheet. It is to describe the chemical process by using a digital model, and to obtain the desired results on the computer by changing various effective conditions. The main component with higher value in citronella oil is high purity citronellal. Due to its boiling point, temperature-sensitive and other issues, the difficulty of distillation process increases. This paper conducts process design and simulation on citronella oil high vacuum distillation process by using Aspen Plus software, obtains the process parameters of citronellal extraction tower, explores the relationship between reflux ratio and the number of theoretical plates, and provides data support for the continuous production of citronellal in citronella oil system.

An energy-saving opportunity in producing lubricating oil using mixed-solventin simulated Rotary Disc Contacting (RDC) extraction tower

Industrial processes are the most energy consuming processes in the world. Modification of these processes helps us with controlling the consumption of energy and minimizing energy loss. Changing raw materials is one of the ways through which we can optimize industrial processes. In this paper, a new solvent mixture (furfural + a co-solvent) was used for the extraction of lubricating base oil from lube-oil cut. It was found that the energy consumption of the new solvent mixture for obtaining a product with the same quality was much lower than the original solvent. By using this new solvent mixture, the operating temperature of the top of tower was reduced by 30 K. This leads to a high reduction in energy consumption in extraction of aromatics from lube oil. At our new extraction process by means of using new solvent mixture, the maximum energy saving was 38% per cubic meter of produced raffinate.

Tritium recovery system for Li–Pb loop of inertial fusion reactor

The best material for a wet wall and blanket of an inertial fusion reactor is selected among Li, eutectic alloys of Li–Pb, Li–Sn and a 2LiF + BeF 2 molten salt mixture called Flibe, judging from their chemical, nuclear and heat-transfer properties. Li 0.17Pb 0.83 is found to be the most promising one because of low Li vapor pressure, moderate melting temperature, good heat-transfer properties under the condition of a KOYO-fast circulation loop operated between 300 and 500 °C. A counter-current extraction tower packed with metallic rashig rings is proposed to extract tritium generated and dissolved in the Li–Pb eutectic alloy. Mass-transfer parameters when He and Li–Pb flow counter-currently through the tower packed with the rings are determined to satisfy the two necessary conditions of a self-sufficient tritium generation rate of 1.8 MCi/day and a target tritium leak rate of 10 Ci/day. It is found that the height of a tower to achieve the 99.999% recovery is comparatively low because of the promising property of a large equilibrium pressure of tritium. In order to mitigate the disadvantage of its high density, which needs a large pumping power, a porous packing material that keeps good contact between He and Li–Pb should be developed in the future. It is found experimentally that D 2 addition in He purge gas is effective to achieve a faster rate of tritium recovery from the Li–Pb flow. The rate-determining step of tritium permeation through a steam generator is determined as a function of a Li–Pb flow rate in a stainless-steel heat-transfer tube.

Solubility, Diffusivity, and Isotopic Exchange Rate of Hydrogen Isotopes in Li-Pb

The diffusion, solution and permeation coefficients of hydrogen isotopes in liquid Li-Pb which is a candidate liquid blanket material for fusion reactors were determined in the temperature range 573-973K using an unsteady permeation method. Each coefficiens was correlated to temperature as follows:The hydrogen permeation flux depends on the square root of pressure at 773-973K. Although the power of pressure declined below 0.4 when temperature was below 673K, the effects of surface resistance were neglected above 673K.The hydrogen solubility in liquid Li-Pbwas found to correlate with a Sievert’s constant.We calculated a height-equivalent to theoretical-plate of a gas-liquid countercurrent extraction tower for tritium recovery rates in liquid Li-Pb to be

Revamping the extraction blocks in vacuum resid deasphalting units

0009-3092/07/4301–0017 © 2007 Springer Science+Business Media, Inc. Deasphalting of vacuum resid with liquefied propane is usually conducted in extraction towers of the gravity type. Standard towers (Fig. 1a) have a small (~7 m) height of the propane and vacuum resid reaction zone and are equipped with baffle trays that consist of metal trays 353 mm wide and 6 mm thick with a step of 68 mm positioned at a 45° angle. This design of the internals insignificantly increases the time the phases are held in the tower and causes formation of “coke” deposits, which are high-melting asphaltite, on the trays. The extraction tower with baffle trays is close to the spray tower in efficiency.

Modernization of the extraction tower in the selective treatment section on the KM-2 unit

Modernization of the extraction tower in the selective treatment section on the KM-2 unit

A STUDY ON MODIFICATION OF THE FURFURAL EXTRACTION TOWER FOR LUBRICATING OIL

ABSTRACT In this paper, the traditional furfural extraction tower for lubricating oil was modified and the rotating disc–packed tower was used to purify the raw oil for the base oil of the lubricating oil. By using Daqing vacuum distillate oil as the raw oil, the refinement effect on the modified furfural extraction tower (the rotating disc–packed tower) were compared with that on the traditional rotating disc contactor and with that on the traditional packed tower. The results showed that by using the modified tower, the quality of the refined oil was improved, the yield of the refined oil increased by 1.05–2.25%, the ratio of the solvent to the oil (S/O) was decreased by 0.2–0.4, and the amount of furfural entrainment in the raffinate reduced by 1.0–2.4%.

Contact devices for extraction towers in units for selective solvent treatment of lube stocks

Contact devices for extraction towers in units for selective solvent treatment of lube stocks