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Ebara Engineering Review No.196

Turbomachinery Blade Optimization by 3-Dimensional Inverse Design Method - 2nd Report, Application to Series Development and Super-Compact Design of Pumps -

by Akira GOTO, Kosuke ASHIHARA, Hiroyuki KATO, & Takaki SAKURAI

The following is a sequel to the first report on the application of the 3-dimensional inverse design method for optimizing the design of turbomachinery blades by numerical analysis of blade shapes in line with ideal flow fields. This report discusses the application of the inverse design method and CFD (Computational Fluid Dynamics) analyses, by which meridional configurations are systematically studied, to series development and super-compact design of pumps. It is pointed out that the development of multiple distinctive series enables mass custom-made designing over a wide flow and specific speed range. The designing of super-compact blades (40% in volumetric size of conventional types) are introduced as well as their performance test results.

Keywords
Turbomachinery, Blade design, Optimization, Inverse design, CFD, Pump, Series development, Suction performance, Meridional configuration, Stall characteristics

Research on MAP Recovery using a Fluidized-bed Crystallized Phosphorus Removal System

by Kazuaki SHIMAMURA, Yukiko MIURA, Yasuhiro HONMA, Hideyuki ISHIKAWA, & Toshihiro TANAKA

Research had been carried out on MAP (Magnesium Ammonium Phosphate) recovery using a fluidized-bed crystallized phosphorus removal system. The main objective of this research was to test the system's performance for removing highly concentrated phosphorus. Test results indicated a tendency for the phosphorus recovery to increase along lower influent phosphorus loads, as well as with smaller particle size of MAP in the reactor. There was also a tendency for the MAP particle size to increase along the elapse of time, a situation which made the treatment instable. This was coped by adding small particle size MAP into the reactor at pre-determined intervals. This resulted in stable treatment with a phosphorus recovery exceeding 80%.

Keywords
Phosphorus recovery, Crystallization, Fluided-bed, Magnesium ammonium phosphate, Particle size, Seed crystal

Nanofiltraion Water Recycling System for Soft Drink Manufacturing Plant

by Hitoshi MIYAKI, Yasunari KOJIMA, Susumu ADACHI, & Kennichi SASAKI

A nanofiltration water recycling system has been developed and implemented for the reuse of water at soft drink manufacturing plants. Relatively low concentration wastewater from various processes is led to the nanofiltration system where soluble organics are removed. The energy-efficient supply pump of this system enables high water recovery under low operation pressure, thus contributing to savings in cost. A CODMn removal exceeding 70% and a TDS removal of about 40% is enabled by this system. Furthermore, a saving in tap water, a conservation of water resources, and a reduction in discharged wastewater is achieved, and the impact on the environment considerably minimized.

Keywords
Nanofiltration, Recycling, Soft Drink Factory

Rapid Effect Disinfection of Combined Sewer Overflows due to Run Offs

by Kazuhiro HASEGAWA, Junichi INAMURA, Yutaka NIIDA, Hideyuki YOSHIDA, Yuichi FUCHU, Kazuhiro KASAI, & Teruo MURAKAMI

A bromine-based, rapid effect disinfection system has been developed for treating combined sewer overflows due to run offs. Performance tests conducted at a pump station revealed that this system was capable of disinfecting coliforms within 18 seconds to 6 minutes, to levels below the standard (3x310 CFU/ ml) set by Japan's Water Pollution Prevention Law. The residual halogen concentration was found to be below 0.05 mg/l. The bromine-based disinfectant used was found to be superior than sodium hypochlorite , conventionally used for such disinfection, while it's degree of safety was about equal to the same.

Keywords
Combined sewer, Combined sewer overflows, Coliform organisms, Disinfectant, Sodium hypochlorite, Bromine based disinfectant, Halogen residual, Pump station, Hypobromous acid, Grit chamber

High Precision, Fine Motion Stage Based on Magnetic Levitation

by Katsuhide WATANABE, Ichiju SATOH, Takahide HAGA, & Shunichi AIYOSHIZAWA

A six-degree-of freedom, magnetic-levitation, fine-motion stage, capable of nanometer-level positioning, was developed for use in clean environments such as in vacuums. The magnetic-levitation stage is a fine motion stage for placing samples on. A magnetic actuator is used for non-contact positioning and displacement sensors detect the position of the stage. A DSP controller enables robust control based on H-infinity control. Positioning tests were conducted from micrometer to nanometer levels and results indicated that the stage was capable of precise positioning over a wide range.

Keywords
Magnetic actuator, Magnetic levitation, H-infinity control, Fine motion stage, Precise positioning, Robust control, Vacuum, Nanometer

Development of a Large Capacity Turbomolecular Pump

by Matsutaro MIYAMOTO, & Hiroyuki KAWASAKI

EBARA's newly developed Large Capacity Turbomolecular Pump includes a mechanism by which the rotational torque and impact force when the rotor crashes become reduced to extremely safe levels. This pump also features a high flow-rate exhaust, comprehensive operability, treatment of exhaust gas constituents by a high-temperature exhaust line, low running costs and a compact design. It is ideal for use in semi-conductor manufacturing processes.

Keywords
Large capacity turbomolecular pump, Torque reducing system, Rotational torque, Rotor crash, Corrosive gas, Impact force, Impact absorbing member, Stress concentration, By-product, High throughput

Development of a Twin-shaft, Synchronous Motor for Dry Vacuum Pumps

by Yoshinori OJIMA, Takanori INADA, Kozo MATAKE, & Naoki IIJIMA

A twin-shaft, synchronous motor had been developed for dry vacuum pumps in an effort to minimize the size as well to enable energy saving. Two motor rotors, directly connected to a pump rotor, undergo a synchronous inversion by one motor stator and drive the pump. The two motor rotor design allowed a compactness by the minimization in the over all motor length. The advantages of a brushless DC motor are fully made use of and high efficiency is enabled not only for rated operations but also for the widely fluctuating load of dry vacuum pumps. The following outlines this motor.

Keywords
Dry vacuum pump, Brushless DC motor, Canned motor, Energy-saving, Twin shaft synchronous, Permanent magnet, Magnetic coupling, Concentrated winding, High efficiency, Sensorless driving

Development of a Trap for Semi-conductor Manufaturing (2nd Report) - Automatic Regeneration Trap -

by Norihiko NOMURA, Tomonori OHASHI, Yuichi IWAMOTO, & Isao YASHIRO

This second report outlines the details and assessment data on the treatment of gas from semi-conductor manufacturing devices using an automatic regeneration trap. This trap contributes to controlling the downtime of semi-conductor manufacturing devices, thus boosting efficiency.

Keywords
Trap, Exchange, Cooling, Washing, Cleaning, Byproduct

Functional Water Production System - D/R/O System -

by Suguru OZAWA

A compact functional water production system has been developed for enabling flexible wet cleaning processes in the manufacturing of semiconductor and other electronic manufacturing. The use of ultra-pure water and chemicals is greatly minimized by this cost-saving system.

Keywords
Functional water, Dissolved gas water, Ozonized water, Degassed water, Wet cleaning, Diffusion dissolving, Semiconductor, Liquid crystal

A Minimization of Environmental Impact of a 300 mm CMP Device

by Tadakazu SONE, Takuji KOBAYASHI, Kimihide NAGATA, Nobuyuki TAKADA, & Takuji HAYAMA

A minimization of environmental impact of a 300 mm CMP (Chemical Mechanical Polishing) device for large-diameter silicon wafers has been realized. Lightweight, low-cost, energy-saving features have been applied to one such device for boosting production with minimized impact on the environment as well as minimized load on the manufacturing facility.

Keywords
Chemical Mechanical Polishing, Increase in wafer dia., Factory load, Consumed energy, Saving energy, Semiconductor production device, D.I. water, Exhaust, Electric power, Cost