Water treatment apparatus

A water treatment apparatus comprising:

• an ultraviolet radiation unit radiating ultraviolet light;
• an ultraviolet radiation part having an elongated tubular configuration, an internal surface, and receiving therein said ultraviolet radiation unit, said ultraviolet radiation unit being spaced from said internal surface of said ultraviolet radiation part for passage of wastewater between said ultraviolet radiation part and the internal surface;
• and
• an oxidizer mixing part that is disposed adjacent to, in fluid communication with, and upstream of said ultraviolet radiation part, wherein said oxidizer mixing part includes
• a minimum cross-sectional area part having an oxidizer suction port for drawing an oxidizer supplied from an oxidizer supply part into wastewater flowing in said oxidizer mixing part and past said oxidizer suction port, wherein the minimum cross-sectional area part is constricted to a first cross-sectional area, and
• a conical part having a tapered configuration that expands from said minimum cross-sectional area part to a large passage part having a cross-sectional area substantially the same as the cross-sectional area of said ultraviolet radiation part, wherein said ultraviolet radiation part has a diameter so that the ultraviolet light has an intensity at said internal surface that is at least 10% stronger than intensity of the ultraviolet light at an ultraviolet radiation surface of said ultraviolet radiation unit.

A water treatment apparatus comprising:

• an ultraviolet radiation unit radiating ultraviolet light;
• an ultraviolet radiation part having an elongated tubular configuration, an internal surface, and receiving therein said ultraviolet radiation unit, said ultraviolet radiation unit being spaced from said internal surface of said ultraviolet radiation part for passage of wastewater between said ultraviolet radiation part and the internal surface;
• and
• an oxidizer mixing part that is disposed adjacent to, in fluid communication with, and upstream of said ultraviolet radiation part, wherein said oxidizer mixing part includes
• a minimum cross-sectional area part having an oxidizer suction port for drawing an oxidizer supplied from an oxidizer supply part into wastewater flowing in said oxidizer mixing part and past said oxidizer suction port, wherein the minimum cross-sectional area part is constricted to a first cross-sectional area, and
• a conical part having a tapered configuration that expands from said minimum cross-sectional area part to a large passage part having a cross-sectional area substantially the same as the cross-sectional area of said ultraviolet radiation part, wherein
• the oxidizer is selected from the group consisting of ozone, an ozone-containing gas, and ozone dissolved in a liquid, and
• the product of a distance D from said internal surface to an ultraviolet radiation surface of said ultraviolet radiation unit and [1000e{2.3(290h[O3G]+320[O3L]+1.86[H2O2])}/100/{2.3(290h[O3G]+320[O3L]+1.86[H2O2])}1.5 (where h:
• a gas holdup, {O3G]:
• gaseous phase ozone concentration, {O3L]:
• liquid phase ozone concentration, and [H2O2]:
• hydrogen peroxide concentration) is in a range from 0.01 to 0.1.

A water treatment apparatus comprising:

• an ultraviolet radiation unit radiating ultraviolet light;
• an ultraviolet radiation part having an elongated tubular configuration, an internal surface, and receiving therein said ultraviolet radiation unit, said ultraviolet radiation unit being spaced from said internal surface of said ultraviolet radiation part for passage of wastewater between said ultraviolet radiation part and the internal surface;
• and
• an oxidizer mixing part that is disposed adjacent to, in fluid communication with, and upstream of said ultraviolet radiation part, wherein said oxidizer mixing part includes
• a minimum cross-sectional area part having an oxidizer suction port for drawing an oxidizer supplied from an oxidizer supply part into wastewater flowing in said oxidizer mixing part and past said oxidizer suction port, wherein the minimum cross-sectional area part is constricted to a first cross-sectional area, and
• a conical part having a tapered configuration that expands from said minimum cross-sectional area part to a large passage part having a cross-sectional area substantially the same as the cross-sectional area of said ultraviolet radiation part, wherein the oxidizer is an ozone-containing gas and the concentration of the ozone in the ozone-containing gas is in a range from 100 to 1,000 g/m3(N).