Method and apparatus for collecting and acclimatizing anaerobic ammonium oxidizing bacteria, and denitrifying water

1. A method for collecting bacterial cells comprising:

feeding water containing ammonium and nitrite to an anaerobic ammonium oxidation vessel to denitrify ammonium and nitrite by anaerobic ammonium oxidizing bacteria provided in the anaerobic ammonium oxidation vessel to form denitrified water containing an amount of the anaerobic ammonium oxidizing bacteria and a sludge containing an amount of the anaerobic ammonium oxidizing bacteria; and

feeding the denitrified water containing an amount of the anaerobic ammonium oxidizing bacteria and the sludge containing an amount of the anaerobic ammonium oxidizing bacteria to a precipitation vessel containing in an upper portion thereof an acclimatization container containing an immobilizing material, to cause the anaerobic ammonium oxidizing bacteria in the denitrified water to be attached to the immobilizing material in the acclimatization container, so that the anaerobic ammonium oxidizing bacteria in the denitrified water are collected, and, at the same time, collecting the anaerobic ammonium oxidizing bacteria of the sludge by precipitating the anaerobic ammonium oxidizing bacteria of the sludge to form a separated sludge of bacteria cells in the precipitation vessel.

2. A method for acclimatizing anaerobic ammonium oxidizing bacteria, comprising introducing the anaerobic ammonium oxidizing bacteria collected by the method according to claim 1 as inoculum into another acclimatization container or another anaerobic ammonium oxidation vessel to be started up.

3. The method according to claim 1 , wherein the method further comprises feeding the separated sludge of bacteria cells from the precipitation vessel to the anaerobic ammonium oxidation vessel.

4. The method according to claim 1 , wherein the separated sludge of bacteria cells is attached to and immobilized on, or entrapped and immobilized in, an additional immobilizing material.

5. The method according to claim 2 , wherein prior to introducing the inoculum, the separated sludge of bacteria cells is attached to and immobilized on, or entrapped and immobilized in, an additional immobilizing material, which is used in the inoculum.

6. An apparatus for collecting bacterial cells, which is configured to carry out the method for collecting bacterial cells according to claim 1 , the apparatus comprising

the anaerobic ammonium oxidation vessel to receive the water containing ammonium and nitrite, the anaerobic ammonium oxidation vessel containing the anaerobic ammonium oxidizing bacteria,

the precipitation vessel downstream from the anaerobic ammonium oxidation vessel to receive the denitrified water and the amount of sludge from the anaerobic ammonium oxidation vessel, wherein the precipitation vessel contains the acclimatization container in an upper portion thereof, the acclimatization container containing the immobilizing material, and

a pipe connecting the precipitation vessel to the anaerobic ammonium oxidation vessel.

7. The apparatus according to claim 6 , wherein the acclimatization container has a structure such that the immobilizing material is prevented from flowing out of the acclimatization container.

8. The apparatus according to claim 7 , wherein the acclimatization container is a box made of a wire mesh or plastic mesh.

9. The apparatus according to claim 6 , wherein the apparatus further includes an additional pipe to return the separated sludge of bacteria cells from the precipitation vessel to the anaerobic ammonium oxidation vessel.