Wet Separator Research Articles

Investigation of the potential of in-line particle concentration measurements in gas particle separation processes by using low-cost particulate matter sensors

In addition to the costly laboratory-based particle measurement devices, low-cost particulate matter sensors for ambient air quality measurements can also be employed for the detection of PM in gas cleaning devices. The ability to spatially resolve the actual level of particle number concentration with high temporal resolution within a gas-particle separation process is of significant value for process monitoring and control. The quantitative reliability of the measurement data from low-cost particulate matter sensors remains uncertain when the particle concentrations in the apparatus exceed the upper measurement limit of the sensors, whether temporarily or permanently. This study examines the potential of low-cost particulate matter sensors for in-line particle concentration measurements in gas-particle separation processes. The measurement performance of the low-cost particulate matter sensors is initially examined under idealised conditions in a dust chamber. This is done in order to quantify the deviations of the low-cost particulate matter sensors in comparison to a state-of-the-art precision laboratory high-cost sensor. Subsequently, both sensor types are installed at a wet separator test facility, following the quantification of their respective measurement performances. The low-cost particulate matter sensors are capable of measuring particle number concentration above their specified limit (up to ≈6.1×104cm−3), depending on the measurement conditions. By applying a 3rd polynomial correction function, obtained from the initial quantification measurement, the low-cost particulate matter sensors are able to reproduce the particle number concentration measured by the high-cost sensor. Furthermore, the low-cost particulate matter sensors are capable of reproducing short-term fluctuations in the particle number concentration.

LIB 습식분리막 열손상에 따른 발화위험성에 관한 연구

LIB-related fires are continuously increasing due to the increase in personal transportation means and the commercialization of electric vehicles. Among the LIB components, the separation membrane is the most important key material for stability, and there is a problem in that it is lost at the scene of a fire and cannot confirm its shape. Accordingly, fire statistics and cases were analyzed, and the experimental outline was established through theoretical consideration of the wet separation membrane, which is the most used as a personal transportation means. As for the experimental method, we conducted a study on the shrinkage rate and tensile strength of the wet separator according to thermal damage for each temperature change with five experimental variables using the wet separator, which plays an important role in the stability of the battery components, as a sample. Through this, the change in shrinkage rate and mechanical properties of the wet separator were derived to understand the fire of lithium-ion batteries caused by damage to the wet separator and to contribute to the fire investigation analysis technique.

Performance evaluation of the VSK separator for treating mineral fines

The separation process is an integral part of many industrial operations. Most of the present-day plants incorporate dry separation units compared to wet separators, due to scarcity of water and process needs. The VSK separator is a dynamic air classifier widely used in closed circuit with High-Pressure Grinding Rolls (HPGR). The HPGR-VSK separator circuit reduces the grinding energy consumption considerably compared to the conventional ball mill-classifier circuits. However, the fundamental principles of VSK separation and its applications in mineral classification/separation are not well reported in the literature. In the present investigation, pilot-scale experiments were carried out on VSK separator by varying feed rate, cage wheel speed, and blower speed to assess the classification and separation efficiency. The experimental results indicated that classification imparts 8.5–38.5% yield to the fines product with a d50 cut-size varying between 18 and 106 µm. Statistical analysis carried out to evaluate the separation efficiency indicated that the cage wheel speed and blower speed are having a prominent effect on the product yield, silica content, and d50 cut-size. The interaction effect between cage wheel speed and blower speed plays a vital role in product quality. The classification and separation efficiency of the unit was evaluated and discussed with respect to different operating parameters. Further, the size separation index (SSI) has been developed to quantify the separation efficiency, which is simpler than the conventional ways of assessments.

On electrolyte wetting through lithium-ion battery separators

The wettability by electrolyte is a critical characteristic of lithium-ion battery separators since electrolyte absorption is essential for ionic transport. Most importantly, fast absorption of electrolyte facilitates the electrolyte filling and wetting processes during the battery assembly. However, theoretical or experimental investigation of separator wettability has rarely been reported, and thus very little quantitative data can be found in the existing literature. In this study, innovative experimental techniques and associated analytical models have been developed to fully characterize the electrolyte wetting behavior through battery separators. Both in-plane and through-plane imbibition processes are investigated. The results show that, electrolyte needs significantly longer time to wet separators than it does for commercial electrodes. The wetting rate depends significantly on the pore size, porosity, and micro-structure of the separators. Electrolyte in-plane wetting is only observed in the separators manufactured by the wet process. Increasing separator porosity and pore size is shown to be substantially increasing through-plane wetting rate. In addition, ceramic coating is shown to increase in-plane wetting but retard through-plane wetting.

The Correlation between Variations of Pressure against Temperature Distribution in Supersonic Subsea Compact Wet-Gas Separators

Conventional wet gas separators are used as a mean to remove free water using gravitational and momentum principle. However, these separators create setback in terms of its efficiency. As an alternative, supersonic compact wet gas separator have been designed in Universiti Teknologi PETRONAS Gas Separation Research Center (UTP GSRC) which uses supersonic flow to separate natural gas and free water for gas transmission pipelines. For the preliminary design, it is important to determine the flow behavior according to the design of the separators. The results can provide information on whether the design can be accepted or improvement should be taken into consideration. It is therefore an objective of this paper to numerically simulate and analyze the correlation between variations of pressure against temperature distribution in the separators design. From the initial pressure variation against temperature results, it can be concluded that the initial pressure ranges from 5 MPa to 6.7 MPa are the best to be used for achieving better separation efficiency.

Effect of Adsorption or Electro-Adsorption of Electrolyte Components at Interfaces on the Electrochemical Performances of Li-Ion Batteries and Supercapacitors

Electrolytes of relevance for high performance Li-ion batteries have to fulfill a variety of criteria such as a high conductivity and phase stability in a wide range of temperatures, a large electrochemical window and high Li+ transference number across interfaces to reduce interfacial resistances and anion concentration polarization. Beyond that, electrolytes should wet separators and electrodes, which is particularly crucial if nano-structured electrodes are used. From this point of view, liquid electrolytes present some advantages over solid or gel electrolytes. Finally the electrolyte must be not too costly or environmentally problematic. Owing to their strong dipolar moment cyclic alkyl carbonates, sulfones and nitriles exhibit high surface tensions which make them unsuitable for wetting polyolefin separators. Another consequence of the use of highly polar solvents is that there are preferentially adsorbed at charged interface and hence, the composition of the adsorbed film will be different from the bulk when binary mixtures of solvent are used, generally composed of a polar and non-polar solvent. As an example, the oxidation potentials of binary solvent electrolytes at the LMNO/electrolyte interface do not depend in a simple manner on the composition of the mixture. Moreover, in order to improve the stability of interfaces, film forming additives, such as vinylene carbonate (VC) or fluoro-alkylcarbonate (FEC), are usually added in small quantities. These additives will compete with the solvent molecules and electrolyte ions, solvated or not, for adsorption at the electrode surface. Hence, it is not surprising to find that the reduction potential of such additives varies strongly with the composition of the electrolyte or even with the addition of a second additive. Given examples will concern the electrochemical performances of TiSnSb conversion active material in the presence of VC and FEC as additives in a mixtures of alkyl carbonates. Other examples will concern the performances of positive active carbon electrodes, designed for use in Li-ion supercapacitors, in order to enlighten the role of solvation on ion electroadsorption in small pores.

Numerical Simulation of Supersonic Subsea Compact Wet Gas Separator for Gas Transmission Pipeline

Conventional wet gas separators are used as a means to remove free water using the gravitational settling and momentum principle. However, these separators possess setback in terms of its efficiency. Alternatively, supersonic compact wet gas separators have been designed in Universiti Teknologi PETRONAS Gas Separation Research Center (UTPGSRC) which uses supersonic flow to separate natural gas and free water. In its preliminary design, determination of the flow behavior according to the design of the separators is important. The result provides information whether the design can be accepted or improvement should be taken into consideration. It is therefore an objective of this paper to numerically simulate and analyze the flow characteristic such as velocity, pressure and temperature distribution correlating with the separator design. From the flow performance results obtained, it shows that the separator design has fulfilled the requirement.

Determination of Nozzle Angle for Flow Performance in Supersonic Subsea Compact Wet Gas Separator

Flow assurances in deep water pipeline have received greater attention in oil and gas industry in order to meet the optimum production of hydrocarbons. However, existence of free water in the gas pipeline decreases production output and increases operational cost and time. Alternatively, anew supersonic subsea compact wet gas separator is design to remove free water from gas transmission pipeline. The key parts of the new design separators is the nozzle.The performanceof supersonic flow is highly related on the design of the nozzle. Therefore, the objective of this paper isto find correlation between the angle of the nozzle against separator flow performance, namely velocity. From the analysis done, it can be concluded thatat nozzle angle of 15°, maximum velocity is achievedthus producing supersonic flow.

Magnetic Separation to Recover Iron Minerals from Flotation Tailings

Large amount of surrounding rocks in Jianshui China has been discarded for many years, and the “rock” is characterized by Cu-Fe poly-metallic constituents and of low grade. A joint process of flotation and magnetic separation was proposed to process the ore. This paper introduces the test results of flotation tailings by a wet drum separator. Results show that iron concentrate assaying 60.21-68.12% Fe at a recovery of 71.9-75.32% can be obtained, when the flotation tailings assays 33.91%Fe. At the same time, a joint process has put forward to make full utilize the “rock”.

Are ionic liquids based on pyrrolidinium imide able to wet separators and electrodes used for Li-ion batteries?

Surface free energy and contact angle measurements were conducted with a series of room temperature ionic liquids (RTILs) based on N,N′-alkyl-pyrrolidinium imide. Wetting characteristics of various separators (Celgard ® and Separion ®) and electrodes (LiCoO 2, Li 4Ti 5O 12 and graphite), commonly used in Li-ion batteries, were performed. Initially, the free surface energies were determined for both smooth polymeric materials, constituent of the separators, and pyrrolidinium RTILs. Experimental results and calculations show that (i) N-methyl-N-pentyl pyrrolidinium imide is the most wetting RTIL whatever the separator used, and that (ii) the separator wettability is one of the most important factor to take into account in electrochemical devices.

Verfahren zur Konditionierung von Rohgasen — Teil 1: Konditionierung durch elektrische Maßnahmen

The operating performance of plant for removal of particulates from gases can be positively influenced by crude gas conditioning and other additive measures. These processes involved introduction of additional material or additional energy into the plant. Set goals are the reduction of particle emissions, reduction of operating costs, adaptation to new boundary conditions, or the opening of new applications for the separators concerned. In the first of three surveys, conditioning by electrical means is considered. An account of the principles of electrically induced agglomeration is followed by a presentation and discussion of the possibilities and consequences of electrical effects applied to filtering separators, inertial separators, and wet separators. Wherever possible, points of practical relevance are also evaluated.

Recent investigations with nozzle scrubbers

The nozzle scrubber is a wet separator simple in design and robust in operation. Hence, it is well suited for installation in existing plants and, generally, a more powerful fan can be forgone since the energy needed to disperse the scrubbing liquid is not delivered by the crude gas (as in the case with venturi scrubbers). All parameters relevant for operation such as specific water consumption, residence time and specific energy consumption have been investigated in detail, and different pneumatic atomizing nozzles (with internal and external mixing of both phases) in various geometrical arrays are examined. The design criteria for the use of the nozzle have been worked out. The effect of particle generation by vaporizing liquid droplets, has for the first time been examined and quantitatively proven on a technical wet scrubber. The results plainly refute the assumption that the concentration of particles realized by the evaporation effect is negligibly low. Possibly contaminations with mass concentrations up to some mg/m 3 are emitted at which the median of mass density distribution ( x 50.3) amounts to 0.05 μm.

The cyclone scrubber – a high efficiency wet separator

AbstractDue to induced turbulent interactions between particles to be separated and the scrubbing liquid present as droplets, very good collection efficiency down to submicron particle size can be achieved as shown by detailed studies [1]. Assumed are suitable flow conditions, a long residence time and a certain droplet size distribution or a special liquid dispersion system. As the name implies, the cyclone scrubber basically consists of a cyclone. This cyclone serves as a contact space in which the interaction between dust particles and scrubbing liquid droplets takes place, and as a droplet separator. Thus, under normal conditions, a water saturated but dust‐ and droplet‐free gas stream leaves the cyclone. The droplets are generated by a pneumatic atomization nozzle, arranged at the cyclone inlet in the direction of flow. A complete theoretical description of the three‐dimensional, three‐phase, non‐steady turbulent flow in the cyclone scrubber has not been possible up to now. The detailed experimental investigations presented in this work, and covering multiple parameters, led to physically based conclusions about the dominant interactions and separation mechanisms involved. Grade efficiencies which did not fall below 0.75, down to a particle size of 0.5 μm, could be measured by an optical particle counter. Collection efficiency of 99.2% was determined by gravimetric analysis of the dust load, according to VDI‐guideline 2066, in the raw and clean gas sections of the dust load, according to VDI‐guideline 2066, in the raw and clean gas sections of the cyclone scrubber.

Magnetic separation equipment for coal applications

This paper covers the use of magnetic separation equipment to remove "tramp iron" from processed coal to protect possible damage to belts, cruhers, hammermills, and screens. It also covers the use of "wet drum separators" in the recovery of magnetite from heavy media plants. Selection criteria are discussed.