Disinfection of Sea Water by Ultraviolet Radiation

Abstract

Data from experiments in artificially and naturally polluted sea water indicate that ultraviolet radiation effectively destroys coliform organisms. The unit developed for this purpose is described and the results obtained are analyzed.

Evaluation of a Small Scale UV-treated Recirculating Depuration System for Oysters (<i>Crassostrea iredalei</i>)

“…The technology of oyster depuration has been well studied in different countries of temperate regions [1,19,20], and is reviewed by Oliveira et al [21]. However, there is very limited scientific information regarding oyster depuration in the tropical regions using a small scale UV-treated recirculating depuration system.…”

Depuration of Bacterial Populations in the Indian Backwater OysterCrassostrea madrasensis(Preston, 1916): Effects on Surface and Bottom Held Oysters

“…The technology of oyster depuration has been well studied in temperate waters (Kelly 1961, Love et al 2010, and is reviewed by Oliveira et al (2011). Most of the studies focused on testing depuration in different types of water (Vasconcelos & Lee 1972, Kasai et al 2011, Ramos et al 2012, and at different temperatures (Chae et al 2009, Love et al 2010, Lopez-Joven et al (Rowse & Fleet 1984, Power & Collins 1990, Love et al 2010, and densities (Lee 2010).…”

Molluscan shellfish depuration

“…Carmelia (1921) reported the purification of oysters using hypochlorite at a concentration of 4±6 mg/L for 12± 18 h. The use of free chlorine species has several drawbacks that limit its effectiveness as a method of shellfish purification. However, some evidence indicates that sodium thiosulfate may itself reduce or inhibit the level of pumping as reported by Kelly (1961). He found that low levels of free chlorine, approximately 0.2 ppm, severely limited or completely shut down the filter-feeding activity of oysters.…”

“…Numerous studies have shown UV light to be effective in inactivating bacteria shellfish (Arcisz and Kelly, 1955;Huntley and Hammerstrom, 1971;Cortelyou, 1954;Kawabata and Harada, 1959;Kelly, 1961) and virus (Fogh, 1955;Hill et al, 1969Hill et al, , 1970 from molluscan shellfish. Numerous studies have shown UV light to be effective in inactivating bacteria shellfish (Arcisz and Kelly, 1955;Huntley and Hammerstrom, 1971;Cortelyou, 1954;Kawabata and Harada, 1959;Kelly, 1961) and virus (Fogh, 1955;Hill et al, 1969Hill et al, , 1970 from molluscan shellfish.…”

“…In most systems the primary source of UV energy is from low-pressure mercury arc lamps. Kelly (1961) examined the limitations of using UV light systems, and found that turbidity, color and dissolved iron salts can affect the transmission of UV light by the aqueous medium, thereby reducing the bactericidal action in the water column and severely limit a UV system's effectiveness. In most UV depurating systems, seawater is exposed to UV light in a flow-through or recirculation system for disinfection before being passed over the shellfish.…”