Accession Number : ADP006910

Title :   Gas Generation in Canals of Tokyo Port,

Corporate Author : BUREAU OF PORTS AND HARBORS TOKYO (JAPAN) DEPT OF CONSTRUCTION

Personal Author(s) : Matsumoto, Y. ; Ishii, Y. ; Shimura, K.

Report Date : APR 1992

Pagination or Media Count : 16

Abstract : Gas generation in canals of the Tokyo port has been studied to identify its mechanism. The major component of generated gas is hydrogen sulfide. Gas emissions from sediment into water are closely related to the depth of water and tide. Emissions per half days were 4 to 11 1/m2 for the 1-m depth of water or less and 1/m2 for water more than 2 m depth. Emission of gas into water began during the ebb tide, indicated maximum value about 1 hr before low tide, reduced during the flood tide, and became almost zero after high tide. According to seasonal variations of generated gas, emissions are greatest in August, being over 100 times more than those in October. Gas emissions are suppressed significantly by sediment dredging; gas emissions measured after dredging were reduced to 1/300 to 1/200 of those measured before dredging. The concentration of hydrogen sulfide was attenuated by water at a rate of 1/3 per meter. Generally, the relationship between sediment thickness and gas emissions was not clearly determined.

Descriptors :   *CANALS, *HYDROGEN SULFIDE, *GASES, DEPTH, DREDGING, EMISSION, FLOODS, HYDROGEN, RATES, SEASONAL VARIATIONS, SEDIMENTS, SULFIDES, THICKNESS, TIDES, VALUE, VARIATIONS, WATER, JAPAN, SYMPOSIA.

Subject Categories : Hydrology, Limnology and Potamology
      Inorganic Chemistry
      Water Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE