mechanical agitator
Recently Published Documents


TOTAL DOCUMENTS

17
(FIVE YEARS 7)

H-INDEX

2
(FIVE YEARS 1)

2021 ◽  
Author(s):  
Hussain Saiood ◽  
Laurie Duthie ◽  
Umut Aybar ◽  
Nestor Molero

Abstract The success of stimulation fluid placement in openhole extended reach wells (ERWs) through coiled tubing (CT) is highly dependent on the depth achieved. Friction forces and helical buckling typically cause early CT lockup, which limits the reach. Organic deposits in the wellbore increases frictional forces causing premature lockup or in some cases even complete blockage. Efficient removal of organic deposits enables CT to reach maximum depth to perform the matrix stimulation. Analysis of these organic deposits was conducted and following a thorough comparative test, a new solvent-external phase emulsion inhibitor was selected to treat the wellbore prior to matrix stimulation. Optimum cleanout methodology was identified for the CT run with a high-pressure jetting nozzle (HPJN) combined with a chemical dissolution effect of the chosen solvent. Focused, high-energy fluid streams loosen any compacted deposits, while the high rate of fluid passing through the tool allows for an efficient cleanout. A matrix stimulation treatment with CT was then executed in the openhole section of the ERW with a TD of 18,773-ft (9800-ft horizontal lateral section) with HCl and emulsified acid systems. By using a solvent-external phase emulsion, only the external phase of the emulsion containing the dissolver is in contact with organic deposits; the remaining internal phase fluid is not. This therefore allows a reduction in total solvent volume. The proposed wellbore cleanout treatment with HPJN reduced the friction coefficient between CT and the completion by 10%. In turn, it was verified that during the operation, an additional 3,320 ft of reach was achieved in the openhole section. Combined with other extended-reach techniques (i.e., mechanical agitator tools, friction reducers), it allowed the 2.0-in CT pipe to reach the TD of the well (18,773 ft). These efforts together maximized the reservoir contact during the matrix stimulation in the openhole section with HCl and emulsified acid systems. Distributed temperature sensing (DTS) methodology was used with the aid of fiber optic installed CT, and the intake profile of the openhole section was mapped. Analysis of the data was applied to optimize the pumping schedule to obtain uniform production contribution across the openhole section. The systematic engineering workflow presented includes the organic deposit diagnostic procedure, laboratory testing, chemical selection, and treatment application. This yields a wellbore treatment that minimizes friction for the remainder of the operation and enables maximum CT reach. This provides more insights of integrated matrix stimulation treatment with CT to overcome the serious challenges present in extended reach openhole wells.


Author(s):  
Uzana Ismail ◽  
Zaifah Che Wil ◽  
Syazwani Idrus

The purpose of this study is to investigate the biogas potential from automotive wastewater codigested with Synthetic wastewater treated in anaerobic reactor. This experiment was run by continuously mixed with mechanical Agitator stirring tank reactor and were established under mesophilic condition at temperature of 38°C. The source of inoculum used in this study were obtained from sewage treatment plant. The experiment was analyzed based on COD removal and biogas production in relation with parameters such as pH, organic loading rate, alkalinity and effect of Zinc and Copper which runs on automotive wastewater. From the result obtains, the reactor condition was unstable during mono digestion of automotive wastewater which aligned with indication of decreasing biogas production, low pH value below 6.0 and low COD removal with value of 63.4%. However, the reactors become stable during co digestion of automotive wastewater with Synthetic wastewater with 0.12 g/L/d OLR and with highest methane production 0.140 L of CH4 / day. The findings illustrate the nutrient available in Synthetic wastewater could enhance the synergistic effect in co digestion with automotive wastewater and therefore resulted with the highest COD removal rates.


Author(s):  
Serban C. Moldoveanu ◽  
Andrew Harrison

SummaryThe present study evaluated the in vitro extraction of benzo[a]pyrene (BaP) from moist snuff into water and into artificial saliva. A similar, previous study evaluated the levels of BaP that remained in the moist snuff after the extraction but did not measure the levels of BaP in the water or saliva extract. The previous study showed that the remaining levels of BaP in the solid material were between 96.3% and 109.6% relative to the initial level of BaP, when the snuff was washed with water and between 99.4% and 108.3% from the initial level of BaP, when the snuff was washed with both saliva and water. Nine moist snuff samples (eight being the same brands as evaluated in the previous study) were analyzed in the present study. Several improvements were made compared to the previous study regarding the extraction conditions. The extraction was performed for 1 h at 37 °C, using a mechanical agitator.The previous study used a commercially available artificial saliva which had an adjusted pH but did not contain enzymes or salts. This saliva was replaced with complete artificial saliva containing salts, mucin and enzymes. The results indicated that the level of BaP extracted in 100 mL water from 5 g of moist snuff at 37 °C ranged between 1.0% and 1.7% of the initial level present in tobacco. For artificial saliva, the extracted level of BaP was between 2% and 3.9% from the initial level, depending on the moist snuff brand. Although the BaP level extracted from the moist snuff with artificial saliva remained very low, the surfactant character of artificial saliva increased BaP extraction relative to water by a factor of approximately two. This study supports the previous reported finding that the vast majority of BaP in moist snuff is not extracted in water or artificial saliva.


2020 ◽  
Vol 24 (1 Part A) ◽  
pp. 231-241 ◽  
Author(s):  
Suresh Vellaiyan

The present article discusses the effect of cerium oxide nanoadditive inclusion on the working characteristics (combustion, performance, and emission) of water emulsified soybean biodiesel-fueled single cylinder Diesel engine. Test fuels with 5% and 10% volume of water in soybean biodiesel along with mass fraction of 100 ppm cerium oxide nanoparticle were prepared using mechanical agitator and ultrasonicator, and the experiments were conducted under different loading conditions in a single cylinder Diesel engine. The experimental results reveal that the emulsion fuel increases the peak in-cylinder pressure and net heat release values compared to pure soybean biodiesel, and cerium oxide nanoparticle inclusion reduces the peak combustion parameters value. The performance parameters such as brake specific fuel consumption and brake energy consumption are significantly improved with emulsion fuel, and the nanoparticle inclusion further improve the performance parameters. At low load conditions, the emulsion fuels increase the hydrocarbon and CO emissions, whereas these emission magnitudes are reduced at high load conditions. As far as the NOx and smoke emissions are concerned, an increase in water concentration directly reduces the emissions irrespective of load conditions. The cerium oxide nanoparticle inclusion reduces the emissions level from the water emulsified soybean biodiesel-fueled diesel engine.


2019 ◽  
Vol 632 ◽  
pp. A21
Author(s):  
E. Oliva ◽  
M. Rainer ◽  
A. Tozzi ◽  
N. Sanna ◽  
M. Iuzzolino ◽  
...  

Context. High resolution spectroscopy at high signal-to-noise ratios (S/Ns) is one the key techniques of the quantitative study of the atmospheres of extrasolar planets. Observations at near-infrared wavelengths with fiber-fed spectrographs coupled to extremely large telescopes are particularly important to tackle the ultimate goal of detecting biosignatures in rocky planets. Aims. To achieve high S/Ns in fiber-fed spectrogrpahs, the systematic noise effects introduced by the fibers must be properly understood and mitigated. In this paper we concentrate on the effects of modal noise in multimode fibers. Methods. Starting from our puzzling on-sky experience with the GIANO-TNG spectrometer we set up an infrared high resolution spectrometer in our laboratory and used this instrument to characterize the modal noise generated in fibers of different types (circular and octagonal) and sizes. Our experiment includes two conventional scrambling systems for fibers: a mechanical agitator and an optical double scrambler. Results. We find that the strength of the modal noise primarily depends on how the fiber is illuminated. It dramatically increases when the fiber is under-illuminated, either in the near field or in the far field. The modal noise is similar in circular and octagonal fibers. The Fourier spectrum of the noise decreases exponentially with frequency; i.e., the modal noise is not white but favors broad spectral features. Using the optical double scrambler has no effect on modal noise. The mechanical agitator has effects that vary between different types of fibers and input illuminations. In some cases this agitator has virtually no effect. In other cases, it mitigates the modal noise, but flattens the noise spectrum in Fourier space; i.e., the mechanical agitator preferentially filters the broad spectral features. Conclusions. Our results show that modal noise is frustratingly insensitive to the use of octagonal fibers and optical double scramblers; i.e., the conventional systems used to improve the performances of spectrographs fed via unevenly illuminated fibers. Fiber agitation may help in some cases, but its effect has to be verified on a case-by-case basis. More generally, our results indicate that the design of the fiber link feeding a spectrograph should be coupled with laboratory measurements that reproduce, as closely as possible, the conditions expected at the telescope.


2019 ◽  
Vol 6 (2) ◽  
pp. 76-83
Author(s):  
V. Yaroshevsky

Aim. The main aim of the research was to compare different methods of fermentation medium energy effi ciency agitation. Methods. The analysis of mass transfer processes in fermenters using different methods of agitation was made. Experimental determination of energy consumption for medium agitation while using a mechanical agitator and an external circulation loop was realized. Estimation of energy effi ciency indices. Results. It was determined that energy effi ciency of agitation by circulation during the cycle of bacterial preparation Planriz BT (Biotechnica) exceeded mechanical agitation 1.3 times in case of aeration, and 2.6 times in the non-aeration mode. Conclusions. The method of agitation by circulation of fermentation medium using an external loop is more energy-effi cient compared to mechanical agitation even in the case of using a slow-speed agitator.


2019 ◽  
Vol 94 (8) ◽  
pp. 2671-2683 ◽  
Author(s):  
Chao Li ◽  
Jiangtao Tian ◽  
Weifei Wang ◽  
Huadong Peng ◽  
Ming Zhang ◽  
...  

Author(s):  
Martin M. Sirk ◽  
Edward H. Wishnow ◽  
Elisha Jhoti ◽  
Marie Weisfeiler ◽  
James Curtis ◽  
...  

2017 ◽  
Vol 19 (3) ◽  
pp. 83-91 ◽  
Author(s):  
Abdessalam Hadjeb ◽  
Mohamed Bouzit ◽  
Youcef Kamla ◽  
Houari Ameur

Abstract Mixing processes are becoming today a huge concern for industrialists in various domains like the pharmaceutical production, oil refining, food industry and manufacture of cosmetic products especially when the processes are related to the mixing of highly viscous products. So the choice of a stirring system for this category of products or fluids must be rigorously examined before use because of the flows which are laminar in the most cases, something that is not good to obtain homogeneous particles or suspensions after the mixing operation. This CFD study allows developing a new geometrical model of mechanical agitator with high performance for mixing of highly viscous fluids. It consists of a combination of two bladed and helical screw agitators. The investigations of the flow structure generated in the vessel are made by using the computer code ANSYS CFX (version 13.0), which allows us to realize and test the effectiveness of the new stirrer on the resulting mixture and power consumption.


Sign in / Sign up

Export Citation Format

Share Document