Development and Performance Tests of a Separator for Removal of Physically Emulsified and Free Oils from Wastewaters (original) (raw)
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Design of Industrial Gravity Type Separators for the Hydrocarbons and Heavy Oil-Water Separations
Hydrocarbon and Heavy Oil-Water Separators are fall in major mass transfer operations and a key component of chemical process industries. They have wide applications in purification and especially in water treatment processes. Many technical papers have been written on the Hydrocarbon and Heavy Oil-Water separator design and vast amounts of information are also available in corporate process engineering design guidelines. The purpose of this work is to provide a comprehensive current design status of Hydrocarbon and Heavy Oil-Water Separators. This type of Hydrocarbon and Heavy Oil-Water Separators which is presented in this work is usually design and used for the separation of hydrocarbons produced during Fischer-Tropsch Synthesis of green diesel from synthesis gas.
Separation of water-oil emulsions in device with enlarged throughflow capacity
2020
The growth of production capacities of industrial enterprises leads to an increase in emission concentration of pollutants and requires the use of separators. This scien tific paper includes the research of separation of emulsions with similar densities. The emul sions with similar properties are separated very slowly, so it is necessary to use special inserts to accelerate the separation process. The authors have chosen inserts with corrugated baffles, located at an angle of 45°, inserts with corrugated baffles, located at an angle of 135°, as well as inserts with cross-corrugated baffles. As a result of experimental research, it was found that with an increase in the emulsion rate inside of apparatus, the separation efficiency decreases, upon the condition that all the studied inserts are installed. When the concentration of hydro carbons in the original mixture is less than 25%, it is most appropriate to use inserts with cor rugated baffles, located at an angle of 45°.
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The objective of this article is to find the optimal dimensions of rectangular plate-type micro-separators in order to enhance the continuous separation of immiscible liquids. The main structure of the separators contains two plates: a hydrophobic (PTFE) upper plate and a hydrophilic (stainless steel) bottom plate which formed the contact surfaces for the fluids in the channel. The devices have two outlets, one for the aqueous phase and the other for the organic phase enabling the continuous separation and withdrawal of the separated phases. Demulsification has been carried out using Shellsol/water emulsion in the presence of a non-ionic surfactant (Tween 80). The separation efficiency is investigated as a function of micro-separator sizes, channel depths, flow rates and plate configurations. The major parameter that controls the destabilization mechanism is the ratio between the droplet size and the channel depth. When the size of the dispersed droplets remains smaller than the height of the separator (channel depths: 25-100 m), creaming is the main demulsification mechanism. Creaming refers to the migration of the dispersed phase of an emulsion, under the influence of buoyancy. The particles float upwards and rise to the top due to the difference in the densities of the particles and the medium. The separation efficiency depends mainly on the residence time of the liquid/liquid mixture in the device regardless of the separator dimensions and channel heights. The separation rate is limited by the removal of the cream layer, formed at the top of the upper plate, from the separator. When the size of the dispersed droplets is larger than the depth of the separator (channel height of 9 m), the separation performance and mechanism become different. The coalescence of the dispersed droplets occurs by passing through the device. The comparison of the data corresponding to creaming and coalescence phenomena emphasizes that the coalescence greatly enhance and accelerate the separation action. The phase separation in the micro-coalescer takes place considerably faster than in the micro-separators.
A comparison of oil-water separation by gravity and electrolysis separation process
Separation Science and Technology, 2020
This study investigates the performance of oil-water separation experimentally using two methods: gravity separation, and electrolysis separation. A factorial design experiment was conducted for gravity separation using a five-variable experimental plan where the factors are as follows: water flow rate, oil flow rate, temperature, number of compartments (2) and (1), and type of separator inlet deflector plate and elbow. The electrolysis separation was conducted using one factor at a time method. It was found that increasing temperature, voltage, and (NaCl) salt increases the performance of oil-water separation, however increasing the pH or volumetric oil to water ratio acts adversely.
Engineering Applications of Computational Fluid Mechanics, 2017
The most widely utilized process of produced water treatment is considered to be use of coalescing or corrugated plate systems in the oil industry because these systems have promising results in the acceleration of the separation process. Even use of corrugated plate systems seem to be effective in separation processes, the geometrical parameters of the plate system could greatly influence the performance of separation process. In this study, a two-dimensional computational fluid dynamics model for coalescing plates was developed to investigate Reynolds number and plate hole shape on separation efficiency. Spacing between plates was set to 12 mm while fluid mixture's Reynolds number varied between 5 and 45 for the computational model. Hole profile and dimensions were determined to be cylindrical, rectangular and ellipse shapes as 10, 15 and 20 mm based on hydraulic diameter definition, respectively. Furthermore, when hole profiles of coalescing plates were chosen to be ellipse and rectangular shapes, separation efficiency nearly stayed constant regardless of hole dimension. The study also reported that change of oil fraction from 5% to 15% caused approximately 30% increase in the separation efficiency. The investigation also revealed Reynolds number of the mixture was inversely proportional to the separation efficiency. It was also found that the highest separation efficiency was obtained for a cylindrical shape with a hole diameter of 15 mm when distance between plates was 12 mm and Reynolds number was 18.
Journal of Membrane Science & Technology, 2015
lighter than the continuous phase, makes the conventional separation techniques difficult to treat oily effluent which contains fine emulsions. The use of microfiltration technology is becoming an increasingly popular alternation for the separation of emulsified oil in lieu of the conventional separation approaches. Membrane separation such as microfiltration (MF), ultra-filtration (UF), nano-filtration (NF), and reverse osmosis (RO) can be used to separate different sized materials [1]. A considerable amount of experimental works and theoretical modelling studies [1-7] in the past two decades that have made possible for the use of low pressure driven membranes for MF of membrane pore size between 0.1 to 5 μm. UF with membrane pore size less than 0.1 μm or a combination of MF/UF polymeric or ceramic membranes are suitable for removing oil content of oilfield produced water. This method involves using low pressure to force the continuous phase to permeate through a membrane into the discharge. The rejection efficiencies are controlled primarily by the choice of the membrane pore size and not by the difference of density in between the dispersed phase and continuous phase. Because of the many unique properties of the membrane technologies such as no phase change, no chemical addition and simple operation, membrane processes usually provide a better option over traditional separation method in oil and gas processing industries.
DESIGN AND FABRICATION OF OIL SEPARATING DEVICE WITH WATER PURIFIER
In metal working industries, various water-based emulsions industries such as sugar factory, food processing, chemical etc are used as coolant to enhance productivity. This emulsion is mixture of water and different types of cutting oils in a specific ratio. The processed water at sugar factory has created pollution. The sugar factory is requiring huge amount of water daily and the processed water has to be wasted to the river. The processed water contains low pH value which causes the land salty which cannot be used for agriculture and this is dangerous. The oil and grease contents in water effects on the land as well as on human beings. Due to chemicals present in water, the water lives are on the edge of destroying. To avoid all these problems, Endless belt type oil skimmers are manufactured. These skimmers consist of geared motor that continuously rotates a Belt made up of special material which allows the oil particles stick to it .these oil particles are then scrapped by scrapper and collected in separate oil collecting bin. The objectives are to separate the oil from water and purify the water from dirt particles.To reuse the water, High efficiency and ability to meet environmental regulations.Belt-type skimmers use an endless belt of stainless steel, elastomer or poly medium, which is lowered into the tank or vessel to be skimmed. The belt passes though resilient wiper blades where the oil is removed from both sides of the medium.
Development of an Inclined Plate Extractor-Separator for Immiscible Liquids
Energies, 2009
A new inclined plates extractor-separator is developed for operation with immiscible liquids in which extraction and separation is achieved in one unit contrary to mixer settlers. The inclined plates extractor-separator combines turbulent jets for contacting, and an inclined plate for separation of the two phases. The inclined plates extractor-separator does not have any moving part inside the vessel. This feature makes it free from the mechanical problems associated with conventional apparatus. The proposed inclined plates extractor-separator was operated in batch mode under various operating conditions to evaluate its performance on the basis of extraction efficiency. Water (light phase) was used as solvent to extract ethyl acetate from a heavy phase pool of tetrachloroethylene and ethyl acetate. The ethyl acetate content was analysed using chromatography. A hydrodynamic study was carried out using high speed photography to understand the mechanisms occurring during mass transfer across the two phases. Furthermore, it was found that the proposed inclined plate extractor-separator reduces the overall operating time by 67% and consumes only 13% of the power in comparison to a mixer-settler. A hydraulic power consumption comparison with a mixer settler and a gullwing extractor-separator is also presented.