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Ebara Engineering Review No.216

Transient Characteristics of Two Wind Turbine Generator Systems having Two Types of Control Methods

by Satoshi SEKIZUKA, Hiroshi OKAZAKI, & Sumio SAITO

This is sequel of a previous paper on the results of an on-site study on two wind turbine generator systems, for which two control methods had been used and compared. In this sequel, the results of a comprehensive performance evaluation on transient characteristic for various electric parameters, versus transitions in power output, are discussed.

Wind turbine, Wind turbine generator system, Propeller type wind turbine, Power control, Constant speed wind turbine, Variable speed wind turbine, Wind speed, Induction generator, Asynchronous generator, Power curve

Development of Functional Polymers by Radiation-Induced Graft Polymerization and Typical Application of these Polymers


Radiation-induced graft polymerization (RIGP) enables the production of separation functional polymers while retaining the physical characteristic of an existing polymer shape. EBARA's RIGP process, in use for more than 2 decades, has been proven effective for manufacturing ion-exchange, non-woven fabric for filtration in air and water purification. We are also involved in the sales of grafted filtration material. The following introduces the RIGP process, including some examples of application.

Radiation induced graft polymerization, Ion exchange, Functional polymer, Non-woven fabric, Chemical filter, Electro-dialysis, Anti-bacterial activities, Electron beam, Polyethylene, Radical

An Innovative Lead-contaminated Soil Remediation Technology-The Electrolysis Reduction Process

by Yutaka OSHIMA, Taizo IWATANI, & Tatsuo SHIMOMURA

An electrolysis-reduction process for remediation of lead-contaminated soil has been developed. This process can accept lead-contaminated silt slurry discharged from a soil-washing process. It is capable of reducing the contamination level to Japan's national criteria for fill-back at the source. This process is unprecedented for remediation of heavy-metal contaminated soil in that no off-site dumping becomes necessary. An electroplating method was applied for the deposition of lead extracted from contaminated silt. Lead in sparingly soluble forms could be extracted from silt, under low pH and reductive potential in the electrolysis reactor. The deposition of metal-lead on the electrode reduces lead-ion concentration in the liquid phase of the silt slurry and enables efficient extraction of lead from the silt.

Electrolysis-reduction process, Contaminated soil, Soil remediation methods, Soil-washing, Lead, Heavy-metal, Plating

Kiln-stoker System for an Industrial Waste Incineration Power Plant

by Takeshi UOZUMI, Satoru INOUE, & Hirotaka AKAGAWA

EBARA's rotary kiln and stoker system is being operated favorably at an industrial waste incineration power plant run by GE Co., Ltd, of Sakai City, Osaka. Various wastes are being treated at this plant such as sludge, plastic, paper, fiber, animal and botanical residue, contagious medical wastes, acid and alkaline liquids, and oil sludge. The system's rotary kiln conducts a well-balanced drying and combusting of such wastes which carry different properties and calorific values, while the downstream stoker and the secondary combustion chamber achieve complete combustion. Heat from the flue gas is recovered as steam in the waste heat boiler, this steam used for generating 265 kW of power by a turbine generator. This steam is also used as a heat source for a sludge drier and a flue gas re-heater.

Kiln-stoker system, Industrial waste, Hospital waste, Waste oil, Waste liquid, Sludge, Waste heat boiler, Steam turbine, Generator, Catalytic reaction tower

Present Situation of International Standard on Full Width Weirs and ISO/TC113/SC2 Meeting in London

by Masao OSHIMA, & Toru ISHIDO

The ISO/TC113/SC2 meeting was held in London on April 27 and 28, 2006. In this meeting a draft international standard (ISO/DIS 1438-1) on flow measurement in open channels using thin plate weirs was discussed, specifying only the Rehbock formula for determining the flow with full width weirs which are applied widely for measuring the discharge flow of large size pumps. Other formulae, including the JIS formula, specified in a previous edition were not considered. The Rehbock formula shows much deviation when used for weir plates higher than 1 m. The authors proposed at the said meeting an amendment in Rehbock formula, for application in the range of weir plate height of over 1 m, referring to the effect of the weir plate boundary layer on the flow coefficient. This paper reports how the meeting proceeded, along with some background regarding the authors' proposal.

ISO, Weir, ISO 1438-1, JIS B 8302, Flow measurement, Thin plate weir, JIS formula, Rehbock formula, Flow coefficient, Boundary layer