Ebara Engineering Review

by Akira GOTO
Further advancement of fluid engineering technology for turbomachinery requires breakthroughs in both “simulation technology” and “design technology”. Thanks to remarkable developments in computational science and high performance computing, “simulation technology”, including fluid simulation, has evolved steadily and dramatically. While the limitations of 2D based “design technology”, including the use of empirical design diagrams, have become evident, a 3D inverse design method using fluid dynamic design parameters has been proposed and successfully applied to multi-objective and multi-disciplinary numerical optimization. Innovations in fluid engineering technology will hopefully continue with strong academia-industry collaboration and rapid progress in information and communication technologies.

Keywords
Turbomachinery, Numerical optimization, High performance computing, Computational fluid dynamics, 3-D design, Inverse design method, Multi-objective optimization, Multi-disciplinary optimization, Explicit knowledge, Academia-industry collaboration

by Junya KAWABATA, Akira GOTO, Takashi ENOMOTO, & Kosuke ASHIHARA
Many stainless steel sheet metal impellers are used in relatively small pumps since they provide excellent volume efficiency. On the other hand, the shape of these impellers is virtually identical to that of conventional cast impellers since the shape of general cast impellers provides an approximate template for the shape of press-formed sheet metal impellers.
To improve the performance and efficiency of stainless steel sheet metal impellers, we have developed an impeller in the innovative shape of an S-shaped meridian, by designing it in the shape of a blade surface through an inverse design method and then narrowing down various parameters by numerical analysis. The performance of the impeller, which was developed to achieve a relative velocity of 120 to 280 (min-1, m3/min, m), was tested in the same casing in which conventional impellers are used, the tests verified that it achieved a pump efficiency improvement of about 0.5% to 14% over conventional impellers.

Keywords
CFD, Inverse design method, Stainless steel sheet metal impeller, Meridian shape

by Ryuichi ISHIKAWA
In Japan, solid waste treatment through incineration was mandated in the Meiji period to improve public sanitation. Since 1963, the enactment of legislation and the provision of government subsidies accelerated the introduction of mechanical furnaces. Exhaust gas treatment technology has also been advanced to address environmental issues, such as pollution problems and dioxins. High-efficiency power generation technology and incineration residue melting technology have been developed for the purpose of contributing to a low-carbon and recycling-based society. Thus, fluidized-bed incinerators and gasifiers have been developed and introduced in addition to mechanical incinerators. As outsourcing to the private sector has become increasingly popular, the provision of total technical services for efficient, safe, and stable waste treatment and the effective use of energy are required.

Keywords
Solid waste, Treatment technology, Technology trend, Incinerator, High-efficiency power generation

by Yoshiro FUKASAKU, Shin KONOMI, & Naoyuki HASEGAWA
The Elliott Group supplies process gas centrifugal compressors to meet diverse market needs in industries ranging from oil refining, to petrochemical production, to the oil & gas industry and even to the production of liquefied natural gas. To meet the growing customer demand for improved compressor performance and reliability and to shorten delivery process, the company has developed and marketed new compressor models since the late 1990s. The Elliott Group seeks to systematically integrate already developed and established components into these new models. However, newly developed compressor components, which address current market needs, have also been introduced. Innovative manufacturing techniques, based mainly on machining, rather than on casting and welding, have been actively pursued.

Keywords
Centrifugal compressors, New compressor models, High speed, Plant capacity increase, Manufacturing technologies, Machining, Market expansion, Petrochemical industry

by Junji KUNISAWA
CMP systems are used for the planarization of the layers in forming the multi-layered interconnects of a semiconductor device. For the improvement of device performance, miniaturization of semiconductor devices has been promoted continually. The materials and processes used in the manufacture of semiconductor devices have become increasingly diversified in the pursuit of cutting-edge technology; consequently, the need for flexible semiconductor manufacturing systems has become even stronger in order to accommodate various processing conditions. Our new CMP system, Model F-REX300X, is equipped with new transport and cleaning mechanisms in combination with the technology that has been cultivated over many years through our CMP projects. This system has both excellent flexibility and high productivity in polishing processes, which enable it to readily accommodate the strict requirements of the most advanced processes.

Keywords
Throughput, Equipment Front End Module, Front Opening Unified Pod, FOUP load port, Overhead, Footprint, Particle, Two-fluid jet, Modularization, Marangoni

by Hiroyuki OSAWA, Sakae SHIMIZU, Koichi TACHIBANA, & Toshiyuki KUTSUWADA
This paper reports the reconstruction of the Sanryo Drainage Pump Station first constructed over 40 years ago.
Regardless of constraints, such as the reuse of the existing casing, increased pump capacity, and change of the impeller type, pump efficiency was increased by about 5%.
A new technique was used to level the pump base on-site. Through the reuse of the existing casing, the renewal of the vertical volute type pump with concrete casing was successfully completed, a job that was previously considered impossible to complete within six months of dry season.
These results provide a guideline for the future reconstruction of large-scale drainage pump stations.

Keywords
Concrete casing, Reconstruction, Increase in pump performance, Vertical volute type mixed flow pump, Reuse, Underground structure, Drainage pump station, Dry season, Impeller, Pump efficiency

by Tomohiro YOSHIDA, & Dai KUDO
Designing the vertical mixed flow pump delivered in 2009 to Las Vegas, United States, presented many technical challenges because its total length of 88 m was the longest in the history of our large pump deliveries. Based on examination informed by our broad experience in the manufacture of vertical pumps and through verification by analysis, we solved such technical challenges as the accumulation of production errors, the difficulty with dimensional tolerance control due to shaft stretch in the longitudinal direction, the dry running of submerged bearings at start-up, and vibration problems. The long pump has been designed to allow simple and efficient installation; it also has reduced weight so as not to exceed the crane capacity. The pump has already been installed on-site and is in commercial operation.

Keywords
Vertical pump, Intake pump, Pump total length, Dimensional tolerance control, Weight reduction, Dry running, Finite element method, Lateral vibration, Torsional vibration

by Tatsuya MIYAMOTO
For prevention of global warming, many countries have started setting energy-saving regulations for pumps and motors. The ErP Directive (Ecodesign requirements for energy-related products/EU) and the GB Standards (China) derive their minimum efficiency requirements for pumps from flow rate and specific speed, while standards such as IEC and NEMA define the efficiency of motors based on outputs. All of these standards are intended to contribute to energy saving by eliminating low-efficiency products from markets which will lead to overall improvement in product quality in the future.

Keywords
Pump, Motor, Energy saving, Efficiency regulation, ErP Directive, GB Standard, International Electrotechnical Commissions, National Electrical Manufactures Association, Specific speed, Flow rate

by Akira SHIMOKURA, Ikuhisa YOKOTA, Takahiro ONO, Tadao ISHIDA, Tsugumitsu MATSUTOMI, & Kazuaki HIROTA

The furnace capacity has been expanded from 45.6 t/d to 67.2 t/d by upgrading the electric furnace transformer from 2000 kVA to 3050 kVA. Spanning about three years from planning to completion, the project has increased the annual throughput of the municipal waste incineration ash melting and recycling process to about 34000 tons. The submerged arc furnace melts raw material based on electric resistance heating by applying electric current directly to the material via electrodes. It supports the reduction melting of waste incineration ash with the addition of coke, facilitating the recovery of reducing slag (main product obtained by slowly cooling molten slag) and valuable materials, such as molten copper and other metals and crude zinc (urban mine). The furnace also contributes to environmental preservation. Thus, the completion of the project establishes one milestone toward the goal of the installation of the second furnace.

Keywords
Electric furnace transformer, Submerged arc furnace, Recycle, Resource, Urban mine, Reduction melting, Minor metal, Environmental assessment for capacity expansion

by Kazuaki WATANABE, & Katsutoshi NARUSE
“Ecotopia Ikehara” is a fluidized-bed gasification and ash melting plant with a capacity of 309 t/d (103 t/d x 3 lines) run by the Kurahama Sanitary Facilities Association in Okinawa. Continuous operation using the third line of the plant was accomplished for 226 days from June 2011 to February 2012. The results of the continuous operation have shown that the CO concentration in stack exhaust gas can be kept to 10 ppm or less during low air ratio operation and that the voluntary criterion for dioxin concentration in ash (0.25 ng-TEQ/g or less) is met without heating dechlorination equipment. Thus, it has been demonstrated that the plant can provide reliable incineration for a long continuous period. With a combustion air ratio of nearly 1.0 in the area up to the slag hole of the ash melting furnace, the transfer factor of lead to slag is less than 1%, which is quite a low value for ash melting furnaces operating in oxidizing atmospheres. In addition, slag quality during continuous operation meets JIS requirements.

Keywords
Fluidized-bed, Gasification, Continuous operation, Transfer factor of lead to slag, Dioxins, Combustion stability, Low air ratio, Ash melting, Fuel consumption, Power generation

by Masami NAGAYAMA, & Tetsuro SUGIURA
Dry vacuum pumps are used to achieve a clean vacuum environment for manufacturing electronic components including semiconductors. However, inlet gases generated during the manufacturing processes often cause deposition of reaction by-products and corrosion inside the pumps; the pumps operate under harsh conditions. The Model EV-M pumps have incorporated various countermeasures against deposition of reaction by-products and corrosion, including optimization of internal temperature, in addition to significant improvements in energy saving performance. These have enabled both excellent endurance and energy saving performance under harsh conditions such as the deposition and etching processes.

Keywords
Dry vacuum pump, Semiconductor, Exhaust gas, Reaction by-products, Corrosion, Internal temperature, Energy saving, Deposition, Etching, Endurance

by Yoshio MINAMI, Yoshitaka MUKAIYAMA, & Tomonori HIRAO
Model UFP-AD has been developed as a downsized version of Model UFP, our automatic plating system for packaging. This model is reasonably priced for finalizing plating conditions in trial production or for small-scale production. It has plating cells arranged in a single row and uses a newly designed, thus simplified, mechanism for loading/unloading and transporting wafers. Only one type of frame is used for the plating chamber so that various types of plating can be handled by changing the arrangement of plating bathes based on the concept of the skeleton-infill system. In addition, a wagon-type stocker is equipped, which enables removal of wafer holders for maintenance even during operation. Such a structure maximizes production volume in spite of its small size.

Keywords
Packaging, Plating, Wafer, Small-scale production, Throughput, Plating bath configuration, Wagon-type stocker, Transporter, Wafer holder, Anode holder

by Teruaki TSUKAMOTO, Masamitsu SASE, & Minoru SASAKI
Treatment plants for municipal solid waste have recently been required to deal with a wide range of issues, such as hygienic treatment, reduction of the burden on the environment, waste volume reduction, material recycling and efficient energy use. In particular, their role as a power generation source has become important. In this background, the construction of the Ozenji Municipal Solid Waste Treatment Center was completed on March 30, 2012. The Center is intended to serve as a key facility for the treatment of municipal solid waste in the northern area of Kawasaki City. This paper introduces and discusses the outline and the operation of the Center. This plant uses Ebara Environmental Plant Co., Ltd.’s advanced stoker technology with the goal of achieving harmony with the surrounding environment based on three main concepts: low carbon emissions, resource recovery, and coexistence with nature. Featuring low air ratio operation based on exhaust gas recirculation and minimizing heat loss through the advanced process of dry exhaust gas treatment, the plant provides efficient power generation and reliable incineration.

Keywords
Solid waste management, Incinerator, Stoker furnace, High-efficiency power generation, Low air ratio combustion, Advanced dry gas treatment system, Exhaust gas recirculation, Forcible air-cooling type stoker

by Hiroyoshi WATANABE, & Yumiko SEKINO
This paper introduces the optimum design process by using the three-dimensional inverse method, CFD (Computational Fluid Dynamics), and multi-objective design optimization method such as multi-objective genetic algorithm, and its applications.
Two applications of the optimum design process for different pump types and purposes of optimization are described. These examples show a wide applicability of the optimization method that uses the blade loading distribution (the hydrodynamic parameter) as a design parameters. The optimum blade loading distribution parameter obtained by this optimization process can be correlated with the performance improvement mechanism for easy understanding, which is advantageous in inheritance of skills. Continuously updating the optimum design database obtained through the optimum design process enables pumps to be quickly customized to meet customer needs.

Keywords
Optimum design, CFD, Three dimensional inverse method, Multi objective design optimization, Response surface, Mixed flow pump, Performance, Inducer, Cavitation, Instability

by Hideaki YAGISHITA
The Guidline for Prevention of Refrigerant Leakage from Refrigerating and Air-conditioning Equipment and Systems (JRA GL-14:2010) was established in Japan on September the 28, 2010. This guideline, made referring to the EU F-gas Regulation, is designed to reduce direct impact on the environment by high-efficiency refrigerating equipment and machines, as well as to reduce the same by refrigerant leakage. The following introduces newly developed low-pressure refrigerant products for centrifugal refrigerating machines. These refrigerants are made reusable by an adsorption process using activated carbon, enabling a reduction in the “visible” leakage amount of the refrigerant to be 1/100 of that of conventional Ebara refrigerant products.

Keywords
Adsorption, Refrigerant, Centrifugal refrigerating machine, Purge, Leakage, Recovery, Activated carbon

by Hiromi SAKACHO, Ugo TURETTA, & Andrea FONGARO
A high speed submersible pump (Model 3TP) for deep wells, equipped with an inverter-driven high speed motor, has been developed. The pump, motor and inverter are assembled in one structure. Its inverter-driven high speed motor achieves a high pump rotation speed, thus allowing less stages and a smaller diameter. The performance of a 4-inch pump is realized in this 3-inch pump. As for 4-inch wells, whose number exceeds 70% of all wells, vinyl chloride pipes are generally used as their casings. Decrepit casings of 4-inch wells tend to be bent and deformed due to subsidence or earthquakes. There are even cases where it is impossible to install new pumps because of this. The Model 3TP fulfills the demand in pump replacement for 4-inch wells.

Keywords
3-inch high speed submersible pump for deep wells, Inverter driven high speed motor, Submersible induction motor with oil filled, Plastic part, High-speed rotation, Overload protection, Dry running protection, Voltage change protection, Arrester protection, Overheating protection

by Yoshihiro AIKAWA, & Tomio MAKINO
EDFrame is a newly developed monitoring and control system which makes use of leading-edge Open ICT technology. By this system data acquisition devices (M2M), installed at various locations in pumping stations and waterworks facilities, as well as at various measurement points, are linked up via broadband, public telephone lines and PHS. This system also features a tool which enables an automatic creation of software and test reports in accordance with the design data of the system. It thus realizes a product which enables a seamless linkage among design, production and testing stages. The EDFrame system is versatile, safe and capable of being extended.

Keywords
Monitoring, Remote control, Simulator, Machine to machine, Virtualization, Cloud, Waterworks, Wastewater treatment, Extendibility, Diversity

by Kazushige KUROSAWA, Daisuke SAKU, Yoji SATO, Tian Shu Ying, & Wang Zheng Bing
Ebara’s first two grate-type furnaces with a waste disposal capacity of 700 t/day (350 t/24 h×2) were delivered to the Weihai Waste-to-Energy Co., Ltd. in Shandong, China, and their performance test was completed in October 2011. The design of the furnace and system considering the low calorific value of garbage in China has achieved the similar combustion performance as in furnaces in Japan, enabling a stable operation. This paper describes the redesigned points for China, results of the performance test, and operational status to date.

Keywords
China, Waste, Incinerator, Stoker, Calorie, Combustion, Environmental, HPCC, Tsingtao

by Hironubu YAMAGUCHI, & Tomoaki OHARA
The facility referred to in this paper is Ebara’s forth fluidized-bed gasification and slagging combustion system designed for local governments in Japan and has been operating for nine years since March 2003. Under the low municipal budget due to the protracted economic downturn, facilities of this kind are required to be stably operated and maintained at low costs. To fulfill these requirements, we achieved the cost reduction and long-term stable operation through the site review of this facility.

Keywords
Long term stable operation, Cost reduction, Fixed-quantity supply, Low air ratio combustion, Combustion chamber temperature, Quantity of steam generation, Electric energy, Award

by Ryuichiro MITANI
Eddy current sensor have been developed for precise monitoring of wafer polishing endpoints in CMP systems. The sensor enhances the preciseness of endpoint detection, greatly improves the planarity of metal films, and thus satisies demands in the ever-progressing semiconductor device market.

Keywords
Eddy current, Rresonance frequency, Excitation frequency, Resistance component, Inductive reactance, Rotary connector, Synchronous circuit

by Hiroshige TAKANO, Takanobu OBA, & Kenichi MORI
Two types of custom-made pump systems regionally produced in Vietnam and applied in the same, have been developed as a solution to constructional and operational problems encountered at existing pump stations. One system features the use of an inclined submersible motor pump, which befits site structural-engineering conditions and enables facilitated operability, while the other features a vertical pull-out pump for facilitated maintenance. Both systems are now being used at new pump stations as well as at an old one. Such regional production and application is expected to grow for its cost-saving and enhanced operability effects.

Keywords
Region production for region consumption, Inclined submersible motor pump, Vertical pull-out pump, Simplification of civil work, Facilitated maintenance work, Climate change, Irrigation / Drainage pumping station, Cost down, Custom-made pump, Vietnam

by Hiroshi UDAGAWA, Taizan SASAKI, & Mitsuyoshi MIZUTANI
Ebara's transverse ventilation system has been installed at Kanamecho and Nakaochiai ventilation stations of Yamate Tunnel, an 11 km tunnel along Tokyo's Metropolitan Expressway. A transverse type system was adopted to match specific structural factors of this tunnel. The following outlines and discusses this ventilation system, including its design.

Keywords
Metropolitan expressway, Yamate tunnel, Tunnel ventilation, Transverse ventilation system, Axial flow fan

by Takahiro NAKAGAWA
EBARA's Microturbine Cogeneration Package features low vibration, low airborne noise and high total efficiency. Its impact on the environment is significantly minimized as exemplified by a NOx content of less than 30 ppm in the exhaust gas. As complete combustion takes place, the emission of unburnt methane gas is less than 1 ppm. Moreover, the package's simple configuration with only a few auxiliary machines, allows easy installation, operation and maintenance. CO2 emission can be significantly reduced by the use of low calorific value, sewage digester gas as biomass fuel. Highly reliable operability is achieved by use of a remote control system for operational support and maintenance. In case of a heated water using package, an electrical efficiency of 29% and a heat recovery efficiency of 50% is achieved versus the fuel energy, constituting a total efficiency of about 79%.

Keywords
Microturbine, Power generation, Cogeneration, Sewage digester gas, Biomass, CO₂ reduction, Remote monitoring system, Grid tie, Low NOx, Low airborne noise