scholarly journals A New Generation of Submersible Electrical Motor Protectors with a Dynamic Labyrinth for Operation in Aggressive Environment with High Concentration of Free Gas and Solids

2019 ◽  
pp. 59-65 ◽  
Author(s):  
A.V. Trulev ◽  
S.F. Timushev
Keyword(s):  
Market Segment ◽  
Centrifugal Pumps ◽  
Operational Environment ◽  
High Concentration ◽  
Aggressive Environment ◽  
Solids Concentration ◽  
Solids Separation ◽  
New Generation ◽  
Negative Factors ◽  
Improve Reliability

In this work, the authors study the problems associated with the operation of oil wells using electric centrifugal pumps. The authors acknowledge the negative factors that lead to an increase in solids concentration in the upper part of the submersible electric motor protectors, higher possibility of end seal failures and shortening of service life of serial products. The replacement of a gravitational labyrinth by a dynamic one in the upper part of the motor seal protector is one of the ways to improve the reliability of the protector in the operational environment with high concentration of gas and solids. The proposed seal protector design makes it possible to considerably increase the estimated efficiency of solids separation (by 300 times), improve reliability, as stable running is ensured even after the failure of end seals, and reduce the mounting length by 25–40 %, resulting in cost saving and improved maintainability as fewer parts are used. This conceptually new operation principle facilitates the creation of a new generation of highly reliable seal protectors, capable of working effectively in challenging well conditions. Thus, the new design should supersede all serial motor seal protectors in conventional wells and add a market segment in complicated wells.

scholarly journals Outstanding Nobility Observed in Cu5 Clusters Reveals the Key Role of Collective Quantum Effects

2021 ◽  
Author(s):  
David Buceta ◽  
Shahana Huseyinova ◽  
Miguel Cuerva ◽  
Héctor Lozano ◽  
Lisandro J. Giovanetti ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Metal Clusters ◽  
Bulk Material ◽  
Chemical Properties ◽  
Quantum Effects ◽  
High Concentration ◽  
X Ray ◽  
Potential Applications ◽  
New Generation

Subnanometer-sized metal clusters often feature a molecule-like electronic structure, which makes their physical and chemical properties significantly different from those of nanoparticles and bulk material. Considering potential applications, there is a major concern about their thermal stability and susceptibility towards oxidation. Cu clusters of only 5 atoms (Cu<sub>5</sub> clusters) are first synthesized in high concentration using a new-generation wet chemical method. Next, it is shown that, contrary to what is currently assumed, Cu<sub>5</sub> clusters display nobility, beyond resistance to irreversible oxidation, at a broad range of temperatures and oxygen pressures. The outstanding nobility arises from an unusual reversible oxidation which is observed by <i>in situ</i> X-ray Absorption Spectroscopy and X-ray Photoelectron Spectroscopy on Cu<sub>5</sub> clusters deposited onto highly oriented pyrolitic graphite at different oxygen pressures and up to 773 K. This atypical property is explained by a theoretical approach combining different state-of-the-art first principles theories. It reveals the essential role of collective quantum effects in the physical mechanism responsible for the nobility of Cu<sub>5</sub> clusters, encompassing a structural ‘breathing’ through concerted Cu–Cu elongations/contractions upon O<sub>2</sub> uptake/release, and collective charge transfer as well. A predictive phase diagram of their reversible oxidation states is also delivered, agreeing with the experimental observations. The collective quantum effects responsible of the observed nobility are expected to be general in subnanometer-sized metal clusters, pushing this new generation of materials to an upper level.

Digestion of municipal sludge by anaerobic sequencing batch reactor

1994 ◽  
Vol 30 (12) ◽  
pp. 161-170 ◽  
Author(s):  
Duk Chang ◽  
Joon Moo Hur ◽  
Tai Hak Chung
Keyword(s):  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Gas Production ◽  
Municipal Sludge ◽  
High Concentration ◽  
Anaerobic Sequencing Batch Reactor ◽  
Mixed Control ◽  
Solids Concentration ◽  
Start Up ◽  
Equivalent Loading

Laboratory experiments were conducted to investigate the performance of the anaerobic sequencing batch reactor (ASBR) for digestion of a municipal sludge. The reactors were operated at an HRT of 10 days with an equivalent loading rate of 0.8-1.5 g VS 1−1 d−1 at 35°C. Solids were accumulated rapidly in the ASBR during start-up period. Flotation thickening occurred in the ASBRs, and its efficiency was comparable to that of additional thickening of the completely mixed control reactor. Solids concentrations in the ASBRs were 2.6 times higher than that in the control. The dehydrogenase activity had a strong correlation with the solids concentration. The ASBRs with 3- and 4-day cycle showed almost identical high digestion performances without adverse effect on digestion stability. The organics removals based on subnatant of the ASBRs were consistently above 90%. Remarkable increase in equivalent gas production of 52% was observed at the ASBRs compared with the control though the control and ASBRs showed similar effluent quality. Thus, digestion of a municipal sludge was possible using the ASBR in spite of high concentration of settleable solids in the sludge.

Suspended Solids Removal Efficiencies of a Barrier Board that Pre-Treats High-Turbidity Raw Water

2012 ◽  
Vol 253-255 ◽  
pp. 969-974
Author(s):  
Jian Liang Chen ◽  
Yi Kuo Chang ◽  
Chin Hsing Lai ◽  
Yun Hwei Shen
Keyword(s):  
Suspended Solids ◽  
Removal Rate ◽  
Initial Period ◽  
Raw Water ◽  
High Concentration ◽  
Solids Concentration ◽  
Gravity Settling ◽  
High Turbidity ◽  
Solids Removal

It tends to produce high-turbidity raw water during the initial period of typhoons or storms and affect the operation of the purifying system. In this research, Raw water suspended solids roughly to 5,000-9,000 mg/l, the removal rate can be to about 70%-90 %, and reduced to 800 mg/l or less, 8 ml/s minimum about 100-400 mg/l. Overall, the quality of effluent water with the overflow water height increased removal rate rose gradually reduce the suspended solids concentration, gravity settling and effective appear, especially the section Ⅳ region (40 cm) removal are more than 80 %, flow 100 ml/s to 84 %, compared with I (10 cm) with 100 ml/s for 74 %, with obvious benefits. The overflow height of the flow of 8 ml/s, and suspended solids by the inlet concentration at 7,400 mg/l to 8,700 mg/l, down to the effluent concentrations are below 300 mg/l, which overflow height of 20, 30, and 40 cm can be reduced to below 200 mg/l, showing that gravitational sedimentation can significantly remove the high concentration of suspended solids.

scholarly journals Pattern formation in drying blood drops

2021 ◽  
Vol 379 (2203) ◽  
pp. 20200391 ◽  
Author(s):  
Michael. J. Hertaeg ◽  
Rico F. Tabor ◽  
Alexander F. Routh ◽  
Gil Garnier
Keyword(s):  
Pattern Formation ◽  
Low Cost ◽  
Volatile Components ◽  
Red Cell ◽  
High Concentration ◽  
Height Profile ◽  
Dirty Water ◽  
Healthy Donors ◽  
Underlying Mechanisms ◽  
New Generation

Patterns in dried droplets are commonly observed as rings left after spills of dirty water or coffee have evaporated. Patterns are also seen in dried blood droplets and the patterns have been shown to differ from patients afflicted with different medical conditions. This has been proposed as the basis for a new generation of low-cost blood diagnostics. Before these diagnostics can be widely used, the underlying mechanisms leading to pattern formation in these systems must be understood. We analyse the height profile and appearance of dispersions prepared with red blood cells (RBCs) from healthy donors. The red cell concentrations and diluent were varied and compared with simple polystyrene particle systems to identify the dominant mechanistic variables. Typically, a high concentration of non-volatile components suppresses ring formation. However, RBC suspensions display a greater volume of edge deposition when the red cell concentration is higher. This discrepancy is caused by the consolidation front halting during drying for most blood suspensions. This prevents the standard horizontal drying mechanism and leads to two clearly defined regions in final crack patterns and height profile. This article is part of a discussion meeting issue ‘A cracking approach to inventing new tough materials: fracture stranger than friction’.

Ultra Heavy Wall Linepipe X65: Double Joint Girth Weld Performances for Severe Applications

2011 ◽  
Author(s):  
Luigi Di Vito ◽  
Gianluca Mannucci ◽  
Roberto Morana ◽  
Antonio Lucci ◽  
Federico Tintori ◽  
...  
Keyword(s):  
Large Strain ◽  
Full Scale ◽  
Corrosion Properties ◽  
Testing Program ◽  
Aggressive Environment ◽  
Girth Welds ◽  
High Level ◽  
New Generation ◽  
Cyclic Straining ◽  
Strain Cycling

Tenaris and Centro Sviluppo Materiali (CSM) launched a Joint Industrial Project aimed at developing heavy wall line pipes. The suitability for very severe applications, involving high service pressures and temperatures, the latter causing large strain fluctuations, in presence of an aggressive sour environment, is analyzed both theoretically and experimentally, including small and full scale pipe models. The full project program aims at developing a new generation heavy wall product, supported by: comprehensive laboratory analysis of the material response under severe mechanical loading in aggressive environment; and full scale testing program, including both pipe and girth weld. Both investigations are mainly addressed to the basic understanding of impact on design criteria from interaction between severe loading and aggressive environment. Three papers have been already presented, in previous OMAE conferences, on this project. In the present paper, main outcomes of laboratory testing activities of the above program on girth welds for double jointing (fill passes by Submerged Arc Welding) are reported. A fitted for purpose special testing program, including mechanical and SSC laboratory scale testing, has been executed. Full thickness longitudinal specimens were extracted crossing girth weld to apply severe strain cycling. The strain cycling has been defined as extreme in terms of resistance against ratcheting for the pressurized pipeline, as deduced in a work reported in one of the previously mentioned papers. The girth welds exhibited very satisfactory performance during severe cyclic straining. Furthermore, mechanical and stress-corrosion properties of the As-Weld girth joint have been compared with the corresponding properties after severe straining and ageing. This comparison highlighted high level of mechanical and SSC resistance, even after the application of severe straining and ageing.

Critical Rotation Speed Calculation and Application Development of Multi-Stage Centrifugal Pumps for Mining

2011 ◽  
Vol 130-134 ◽  
pp. 1119-1122
Author(s):  
Wei Li ◽  
Wei Dong Shi ◽  
Xiao Ping Jiang ◽  
Yan Xu
Keyword(s):  
Rotation Speed ◽  
Computational Method ◽  
Secondary Development ◽  
Centrifugal Pumps ◽  
Operational Environment ◽  
Application Development ◽  
Critical Rotation ◽  
Multi Stage ◽  
Pump Shaft ◽  
Critical Rotation Speed

Multi-stage centrifugal pumps for mining are widely used in mining and smelting industry. The operational environment in coal mine sewage is very harsh, so pump shaft and bearing failure happens frequently. In order to avoid disaster damage caused by failure of the pump shaft due to resonance, it is quite necessary and urgent to calculate critical rotation speed of the pump shaft. A calculation program of critical rotation speed for multi-stage centrifugal pumps for mining was developed using the secondary development tool of Object ARX, to give the computational method of the pump shaft load and static deflection and to achieve calculation of the critical speed, and which avoided the disadvantage of the traditional method. The practical application indicates that the program of critical rotation speed is convenient, intuitive and calculation accurate. It not only improves the work efficiency, but also reduces the labor intensity, so the program will have a good application prospect.

Paste Thickening of Iron Tailings with Vibrating Lamella Thickener

2013 ◽  
Vol 690-693 ◽  
pp. 3570-3575
Author(s):  
Xing Long Zhou ◽  
Qi Chun Xie ◽  
Xiao Ming Zhang ◽  
Zhi Xin Shi ◽  
Chun Qiu Tian ◽  
...  
Keyword(s):  
Processing Plant ◽  
High Solids ◽  
Inclined Plate ◽  
Iron And Steel ◽  
Solids Concentration ◽  
Mining Safety ◽  
Solids Content ◽  
New Generation ◽  
Inclined Plates ◽  
Main Operating

Vibrating lamella thickener (VLT) developed by Kunming University of Science and Technology is a new generation of inclined plate settling device, and in this device such long-standing problems in traditional lamella thickener (LT) as material bonding and blockage between channels in inclined plates, material deposits and blockage in cone bucket, as well as unsteady discharging of high solids underflow, etc. are effectively resolved, through periodic vibration of inclined plate modules, the use of built-in device for removal of deposited material on cone wall and of forced discharging device for high solids underflow. Paste discharging is now a new way for the effective treatment of tailings in recent years, due to its superiority for mining safety and environmental protection. The industrial tests for paste thickening of iron tailings were carried out in a mineral processing plant of Mining Co., Ltd. of Panzhihua Iron and Steel Group, using a ZXNQP-32 VLT. In the test the size distribution and settling characteristics of the tailings were analyzed, and the main operating parameters in the VLT were tested under the natural settling and flocculated settling conditions, respectively. The results of test indicate that the solids concentration of underflow from the VLT is capable of reaching higher than 70%; meanwhile, the solids content in overflow from the VLT is as low as less than 300 mg/l while flocculant is added in the ore pulp for pretreatment and such an overflow can be directly discharged into environment or be recycled in the plant. It is thus concluded that VLT is effective for paste thickening of iron tailings.

Experimental and Numerical Investigation of a Counter-Rotating Mixed-Flow Single Stage Pump

2015 ◽  
Author(s):  
Stefano Tosin ◽  
Jens Friedrichs ◽  
Andreas Dreiss
Keyword(s):  
Characteristic Curve ◽  
Speed Ratio ◽  
Centrifugal Pumps ◽  
Mixed Flow ◽  
Pump Design ◽  
Machine Performance ◽  
Novel Approach ◽  
Specific Speed ◽  
Definition Of ◽  
New Generation

A prototype of a new generation of centrifugal pumps has been developed, with aim to improve typical weaknesses like narrow operable range due to slip and incidence losses in off-design conditions. The peculiarity of this pump is the absence of any stator blade, which has been substituted with a counter-rotating radial impeller. According to an exhaustive literature survey, the usage of a mixed flow impeller as a front rotor, followed by a radial-flow impeller seems to be a novel approach in pump design. The combination of a high specific speed impeller with a low specific speed rotating diffuser produces a flexible adaptability against aforementioned limits. Keep on adding energy to the fluid instead of just diffusing the flow, permits to reach a downsized hydraulics and an increased entire machine power density. The characteristic of such a pump needs to be analyzed as 3D-surface, both speeds are actually independent and for a fixed discharge the head rise and efficiency become surfaces. A new definition of optimized characteristic curve, with variable speed ratio, could be identified based on those performance maps. A special test rig has been built to measure the machine performance, distinguishing the mechanical losses of both shafts separately with no-load measurements. The sensitivity of the system on speed ratio variation has been explored. The experiments show the presence of different best speed ratios which maximize alternately the head or the efficiency. Additionally, the results confirm the possibility to expand the working range acting on the rotational speeds. Head rise and efficiency curves with varying speed ratio, as functions of the flow rate are finally shown using several diagrams, highlighting the advantages of this new design.

MONOCLONAL PURIFIED FACTOR VIII:C (MONOCLATE) TREATMENT IN A PREVIOUSLY UNTREATED HAEMOPHILIA

1987 ◽  
Author(s):  
L Parapia ◽  
A Minford ◽  
J B Hamilton
Keyword(s):  
Factor Viii ◽  
T Cell Subsets ◽  
Hiv Status ◽  
High Concentration ◽  
Lower Lip ◽  
Normal Limits ◽  
Viral Particles ◽  
Antibody Titres ◽  
New Generation

Monoclate is a new generation of Factor VIII concentrate produced by purification using mouse monoclonal anti-Factor VIII:R antibody. As the- Factor VIII:C does not interact with the antibody it can be eluted by disrupting the Factor VIII:C - Factor VIII:R complex using a high concentration of calcium ions. The eluted Factor VIII:C is concentrated and purified. The method of manufacture has demonstrated efficacy in the elimination of infectious viral particles.The first “virgin” haemophiliac to be treated by this has completed 20 weeks follow-up. The patient, a child of 18 months with a Factor VIII:C level of 2.8%, was treated with 190 × 4 units of the Factor VIII concentrate for a severe cut of the lower lip.The HIV status has remained negative. The AST and ALT enzymes have remained within normal limits. Other parameters which have remained normal are Gamma GT, WBC and lymphocyte counts, T cell subsets and B cell ratios.The patient has remained well and no side effects have been noted. Mouse antibody titres are being carried out and the results will be presented at the conference.

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