News

New RKN Series

Activated carbon manufacturer Kuraray Chemical Co., Ltd. (Headquarters: Osaka; President: Shobu Minatono; hereafter "Kuraray Chemical") has developed a new type of carbon molecular sieve (CMS, a specialized function activated carbon) capable of separating nitrogen and oxygen more effectively than conventional products through the use of air. Employing that carbon molecular sieve, Kuraray Chemical will launch sales of the new RKN series of nitrogen generators, which are 40% more compact than previous generators, from June 2006. This development will eliminate the need for liquid nitrogen tanks and cylinders utilized by consumers of conventional liquid nitrogen, reducing the space needed to generate and use nitrogen in plants and worksites.

Furthermore, by attaching the industry's first energy-saving and purity-stabilizing system as an option, electrical consumption can be cut by up to 40% compared with conventional products, and the density of residual oxygen that comes with changes in the flow volume of nitrogen gas can be stabilized. In consideration of the environment, the body of the generator makes use of a solvent-free powder coating.

Nitrogen generators are used in the food processing industry to prevent quality changes in foodstuffs, and in the machinery and metal industries for non-oxidation cutting in laser processing machinery, as well as for vacuum heat treating, hardening and bright heat treating. In the chemical industry, they are used for injection molding of resins, and to prevent oxidation of products, explosion or combustion. In the manufacturing of electronic components, nitrogen generators have uses in flow and reflow soldering employed in packaging, while in the steel industry they are used for air blocking and for blowing and stirring. Aside from these varied uses, the nitrogen generator is recently drawing attention as an apparatus that enables the elimination of lead solder in the packaging process for printed circuit boards. The move to lead solder-free packaging is gaining momentum worldwide due to concerns over environmental preservation, and because lead-free packing improves wetting characteristics to a condition near that of a no-oxygen environment, it enables the preservation and enhancement of product quality.

In 1980, Kuraray Chemical began selling nitrogen generators that featured a PSA system made possible through a carbon molecular sieve, and cumulative sales have reached over 2,000 units. Kuraray Chemical has maintained its leading market share in Japan for over 10 years. We also began a collaborative effort with Iwatani International Corporation from 2002 to lead the industry in establishing maintenance bases in Shanghai and Guangzhou, and have gained a solid foothold in the China market.

Before they go on sale, Kuraray Chemical will exhibit the generators at the 35th INTERNEPCON JAPAN, to be held from January 18-20 at Tokyo Big Sight.

1. RKN Series of Nitrogen Generators

1) Characteristics

  • (1) Through the development of a carbon molecular sieve that separates nitrogen and oxygen with high efficiency, the generators have been made 40% more compact, enabling effective use even in plants with limited floor space.
  • (2) Makes possible up to a 40% reduction in consumption of electricity through an energy-saving and purity-stabilizing system that can be attached as an option.
  • (3) In concern for the environment, utilizes a powder spray coating free of organic solvents.

2) Size (Comparison of conventional RK-15 with new RKN-15)

  Conventional RK-15 New RKN-15
Nitrogen Generating Volume 20.0Nm³/H 20.0Nm³/H
External dimensions
(width×height×depth in mm)
1750× ~1900× ~800 1250× ~1720× ~700

*In addition to the RKN-15, we also plan to launch the RKN-22 (nitrogen generating volume of 30.0Nm³/H) and the RKN-30 (nitrogen generating volume of 40.0Nm³/H)

3) Sales Price

Several million to ten million yen per unit

4) Sales Targets

First year ¥500 million
Three years later ¥1 billion
What is a PSA nitrogen generator?

Nitrogen generating equipment includes systems based upon cryogenic separation (utilizing the difference with boiling point), membrane separation and pressure swing adsorption (PSA). PSA is widely recognized in Japan and abroad as a generating apparatus that can separate air at ordinary temperatures and is simple to maintain. It also produces nitrogen with 94% to 99.999% purity.

PSA also utilizes a carbon molecular sieve capable of separating nitrogen and oxygen molecules in the air. The difference in adsorption speed is caused by each size of the nitrogen (4.2×3.0Å) and oxygen (3.8×2.8Å) molecules as they pass through the narrowed, ultra-fine pore diameter of the activated carbon. Because the difference in adsorption speed is large at the beginning of adsorption, separation of nitrogen and oxygen takes place within the brevity (1-2 minutes) of that early stage. When pressure is added during adsorption, small oxygen molecules are absorbed, while absorbed oxygen molecules are desorbed if pressure is reduced. If adsorption and desorption are repeatedly conducted in two chambers equipped with carbon molecular sieves, nitrogen can continuously be separated out.

2. Energy-Saving and Purity-Stabilizing System

1) Characteristics

(1) Significant energy saving results
The amount of air consumed can be reduced in proportion to the flow volume of the product nitrogen gas, holding down the amount of electricity consumed by the air compressor to save energy.
(2) Stabilization of oxygen density
Variations in volume flow of nitrogen gas leave residual oxygen. The system regularly stabilizes the density (concentration) of that residual oxygen within a range of ±30% of settings. Unstable oxygen concentration is a source of defective product in the printed circuit board packaging industry.

Kuraray Chemical Co., Ltd.

Headquarters Shin Hankyu Building 9F, 1-12-39 Umeda, Kita-ku, Osaka 530-8611;
President Shobu Minatono
Established 1940
Capital ¥600 million (Wholly-owned by Kuraray)
Employees 220 (as of December 2005)
Business Sites Osaka Headquarters, Tokyo Head Office, Fukuoka Sales Office, Tsurumi Plant (Bizen City, Okayama Prefecture), Cenapro Chemical Corporation (joint venture company) (Philippines), Kuraray Chemical (Ningxia) Environmental Industry Co. Ltd. (wholly owned subsidiary) (Ningxia, China)
Business activities General manufacturer of activated carbon, activated carbon business, performance activated carbon business and apparatus business