Chiyoda Corporation

Nkk Corporation

Nippon Furnace Co., Ltd.

Nobuhiro Onda

Hiroaki Nishijima

Nobuo Moriya

Kouji Sakashita

Sachio Asaoka

Tetsuo Maejima

Makoto Yasui

Tsuneo Watanabe

Noriyuki Yoneda

Akio Shindo

Takashi Imazeki

Ryuichi Inaba

Athumi Kukidome

Kaoru Shimogawara

Keiji Shimoda

Takeshi Kouzaki

Eiji Watanabe

Yoshimi Shiroto

Shuhei Wakamatsu

Yoshiharu Kataoka

Tomoyuki Mikuriya

Susumu Mochida

Toshiaki Yoshioka

Takao Kameda

Akihiro Fujimori

Hirotoshi Koga

Tadahiro Araake

Athumi Kukudome

Takeo Nikkuni

Karou Shimogawara

Ryoichi Kawabata

A combustion air supply apparatusof alternating heat exchange type supplies combustion air and discharges combustion exhaust gas at a flow velocity of 80 to 200 m/sec. A burner assemblyis configured in such a manner that low-caloric fuel gas is pre-heated with heat of pre-combusting high-caloric fuel gas before the low-caloric fuel gas reaches a mixing starting space CA in the combustion chamber where the pre-combusting high-caloric fuel gas and the low-caloric fuel gas come to burn together in a full scale in the mixing starting space CA. When an air amount of the combustion air supplied through the high-temperature air supply ports of the plurality of fuel gas combustion apparatuses is defined as Qand an air amount of the pre-combustion air to be mixed with the high-caloric fuel gas, supplied from the fuel gas combustion apparatuses, is defined as Q, a total air amount (Q+Q) is 1.02 to 1.10 times more than a theoretical air amount QS required for combustion, and a ratio of Q/(Q+Q) is 0.011 to 0.047.

Reactor employing high-temperature air combustion technology

High quality bisphenol A is produced from a neutral crystalline adduct of bisphenol A and phenol by fusing the adduct in an atmosphere having a maximum oxygen content of 0.005 % by volume, followed by evaporation of liberated phenol. The crystalline adduct may be mixed with an aliphatic carboxylic acid before the fusion to reduce the coloring of the product. When an acidic crystalline adduct is used, the use of a strong alkali salt of an aliphatic carboxylic acid is suitably used. Interior surfaces of the apparatuses for carrying out the fusion and evaporation are desirably washed with an organic solvent to remove oxygen therefrom. The evaporation of phenol is suitably performed by two stage steam stripping wherein a used stripping gas obtained in the second stage is employed as a stripping gas in the first stage while steam is used as the stripping gas in the second stage.

Process for the production of bishenol A

High quality bisphenol A is produced from a neutral crystalline adduct of bisphenol A and phenol by fusing the adduct in an atmosphere having a maximum oxygen content of 0.005% by volume, followed by evaporation of liberated phenol. The crystalline adduct may be mixed with an aliphatic carboxylic acid before the fusion to reduce the coloring of the product. When an acidic crystalline adduct is used, the use of a strong alkali salt of an aliphatic carboxylic acid is suitably used. Interior surfaces of the apparatuses for carrying out the fusion and evaporation are desirably washed with an organic solvent to remove oxygen therefrom. The evaporation of phenol is suitably performed by two stage steam stripping wherein a used stripping gas obtained in the second stage is employed as a stripping gas in the first stage while steam is used as the stripping gas in the second stage.

Process for the production of bisphenol A

High purity, crystalline adduct of bisphenol A and phenol is produced multi-stage crystallization of a phenolic slurry of bisphenol A with a crystal separation and washing step being interposed between each of the two stages. Each of the crystallization stage includes a series of crystallization towers operated at decreasing temperatures. The crystallization of the slurry is performed by continuously discharging a portion of the slurry from each of the crystallization towers, introducing the discharged slurry into one or more coolers and then recycling the cooled slurry to the tower. Another portion of the slurry in each crystallization slurry is continuously discharged, heated for dissolving fine crystals of the adduct and then recycled to the crystallization tower so that large crystals are grown in each of the crystallization steps. An apparatus having a plurality of coolers and suitable for effecting the above crystallization is also disclosed.

Process for the production of crystalline adduct of bisphenol A and

Process for the production of bisphenol A.

A selector valve used for distributing and combining process flow. This valve comprises an open-ended cylindrical casing, a valve seat secured to the casing, an inlet hole extending coaxially with the casing through the valve seat, a plurality of outlet holes extending through the valve seat and arranged in a circle concentrical with the casing, a valve body fitted in the casing and rotatable about its axis, a U-shaped passage formed in the valve body such that its one end opens at a position coinciding with the inlet hole and its other end opens at a position meeting the circle, a spring provided within the casing for urging the valve body toward the valve seat so that the valve body is maintained in pressure contact with the valve seat, a driving mechanism for rotating the valve body through a desired angle so that the inlet hole can be in fluid communication with selected one of the outlet holes through the U-shaped passage, an annular groove formed on the surface of the valve body to define an annular, close space between the valve seat and the valve body at a position inside of the circle and a discharge hole extending through the valve seat at such a position as to be in fluid communication with the space.

Selector valve

Growing community of inventors

Tokyo, Japan

Nobuhiro Onda