UV/O3/H2O2 ADVANCED OXIDATION REACTOR AND PROCESS

Abstract

A UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor includes a water inlet pipe, a water outlet pipe, an ultraviolet reactor, an H.sub.2O.sub.2 adding device and an O.sub.3 adding device. The ultraviolet reactor has a plurality of ultraviolet lamps embedded therein, and the ultraviolet lamps are arranged at an angle with respect to partition plates. The water inlet pipe is connected to a water inlet in a lower portion of the ultraviolet reactor, and the water outlet pipe is connected to a water outlet in an upper portion of the ultraviolet reactor. The H.sub.2O.sub.2 adding device and the O.sub.3 adding device are arranged on a connecting pipe of the water inlet pipe. After raw water is pressurized, H.sub.2O.sub.2 is added into the raw water through the H.sub.2O.sub.2 adding device, then ozone is added in the raw water through a water injector, and finally the raw water enters the ultraviolet reactor.

Claims

1. A UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor, comprising a water inlet pipe, a water outlet pipe, an ultraviolet reactor and an H.sub.2O.sub.2 adding device, wherein the water inlet pipe is connected to a water inlet in a lower portion of the ultraviolet reactor, the water outlet pipe is connected to a water outlet in an upper portion of the ultraviolet reactor, and the H.sub.2O.sub.2 adding device is arranged on a connecting pipe of the water inlet pipe; an O.sub.3 adding device is arranged on the connecting pipe of the water inlet pipe; the O.sub.3 adding device comprises a gas source, an ozone generator and a water injector; the H.sub.2O.sub.2 adding device comprises a H.sub.2O.sub.2 storage tank, a metering pump and a static mixer; after raw water is pressurized, H.sub.2O.sub.2 with a certain concentration is added to the raw water through the H.sub.2O.sub.2 adding device, then ozone with a certain concentration generated by the ozone generator is added to the raw water through the water injector, and finally the raw water enters the ultraviolet reactor; and the ultraviolet reactor is configured as a curvet structure that has a bottom end provided with an inlet and a top end provided with an outlet, and that has a plurality of ultraviolet lamps embedded therein, and the ultraviolet lamps are arranged at an angle with respect to a plurality of partition plates.

2. The UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 1, wherein the ultraviolet reactor comprises an ultraviolet reactor cavity and the ultraviolet lamps, each of the ultraviolet lamps consists of a plurality of ultraviolet lamp tubes which are installed at an angle of 15-30, and a distance between the ultraviolet lamp tubes is a reciprocal of a difference between a light transmittance of pure water and a light transmittance of a water sample; a length-width-height ratio of the ultraviolet reactor cavity is 3:2:1, 45 baffle plates are arranged at inner corners of the ultraviolet reactor cavity, and the baffle plates arranged at the opposite corners of the cavity are parallel to the ultraviolet lamp tubes; and the partition plates used for fixing the ultraviolet lamp tubes are arranged in the cavity.

3. The UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 2, wherein a plurality of ultraviolet lamp bushings are respectively arranged on the ultraviolet lamp tubes, and a number of the ultraviolet lamp tubes depends on power of the ultraviolet lamps, an ultraviolet intensity, an exposure time and a UV dose in to-be-treated water.

4. The UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 1, wherein the H.sub.2O.sub.2 adding device comprises a storage tank, a metering pump and a static mixer.

5. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 1, wherein the process has following process parameters: an H.sub.2O.sub.2 dose is 0.5-5 mg/L; an O.sub.3 dose is controlled to 0.5-1 mg/L; a hydraulic retention time is not greater than 5 min, and a flow rate is not greater than 0.15 m/s; and a UV dose is 200-300 mJ/cm.sup.2.

6. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 1, wherein when all devices are started, following reaction is carried out in the reactor: ##STR00003##

7. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 2, wherein the process has following process parameters: an H.sub.2O.sub.2 dose is 0.5-5 mg/L; an O.sub.3 dose is controlled to 0.5-1 mg/L; a hydraulic retention time is not greater than 5 min, and a flow rate is not greater than 0.15 m/s; and a UV dose is 200-300 mJ/cm.sup.2.

8. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 3, wherein the process has following process parameters: an H.sub.2O.sub.2 dose is 0.5-5 mg/L; an O.sub.3 dose is controlled to 0.5-1 mg/L; a hydraulic retention time is not greater than 5 min, and a flow rate is not greater than 0.15 m/s; and a UV dose is 200-300 mJ/cm.sup.2.

9. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 2, wherein when all devices are started, following reaction is carried out in the reactor: ##STR00004##

10. A process of the UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor according to claim 3, wherein when all devices are started, following reaction is carried out in the reactor: ##STR00005##

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a process flow diagram of the invention;

[0016] FIG. 2 is a perspective view of an ultraviolet reactor of the invention;

[0017] FIG. 3 is a front view of the ultraviolet reactor of the invention;

[0018] FIG. 4 is a left view of the ultraviolet reactor of the invention; and

[0019] FIG. 5 is a top view of the ultraviolet reactor of the invention.

[0020] In the figures: 1, water inlet pipe; 2, water outlet pipe; 3, ultraviolet reactor; 4, H.sub.2O.sub.2 adding device; 5, O.sub.3 adding device; 6, ultraviolet lamp; 7, cavity of ultraviolet reactor; 8, ultraviolet lamp tube; 9, baffle plate; 10, partition plate; 11, ultraviolet lamp bushing; 12, water inlet of ultraviolet reactor; 13, water outlet of ultraviolet reactor; 14, static mixer; 15, water injector; 16, flowmeter; 17, metering pump; 18, check valve; 19, gate valve; 20, H.sub.2O.sub.2 storage tank; 21, ozone generator; 22, liquid oxygen tank.

DESCRIPTION OF THE EMBODIMENTS

[0021] The invention is specifically described below in combination with the accompanying drawings and embodiments.

[0022] FIG. 1 is a process flow diagram of the invention.

[0023] The invention provides a UV/O.sub.3/H.sub.2O.sub.2 advanced oxidation reactor comprising a water inlet pipe 1, a water outlet pipe 2, an ultraviolet reactor 3, an H.sub.2O.sub.2 adding device 4, and an O.sub.3 adding device 5.

[0024] The ultraviolet reactor 3 is of a bottom-inlet top-outlet curvet structure and has a plurality of ultraviolet lamps 6 embedded therein, and the ultraviolet lamps 6 are arranged at an angle with respect to partition plates 9. The hydraulic retention time is not greater than 5 min, the flow rate is not greater than 0.15 m/s, and the UV dose is 200-300 mJ/cm.sup.2.

[0025] The water inlet pipe 1 is connected to a water inlet 12 in a lower portion of the ultraviolet reactor, the water outlet pipe 2 is connected to a water outlet 13 in an upper portion of the ultraviolet reactor, and the H.sub.2O.sub.2 adding device 3 and the O.sub.3 adding device 4 are arranged on a connecting pipe of the water inlet pipe 1.

[0026] The H.sub.2O.sub.2 adding device comprises a storage tank, a metering pump and a static mixer, and the H.sub.2O.sub.2 dose is 0.5-5 mg/L.

[0027] The O.sub.3 adding device comprises a liquid oxygen tank 22, an ozone generator 21 and a water injector 15. The liquid oxygen in the liquid oxygen tank is depressurized by a depressurization valve of the liquid oxygen tank and then enters the ozone generator, and ozone generated by the ozone generator is finally added into a system through the water injector after the output dose of the ozone is regulated by an air pump, and is prevented by a check valve from flowing back. The O.sub.3 dose is controlled to 0.5-1 mg/L.

[0028] Raw water is pressurized by a pump and then enters the advanced oxidation system with the flow rate regulated by a gate valve 19 and a flowmeter 16. H.sub.2O.sub.2 with a certain concentration is added to the raw water through the H.sub.2O.sub.2 adding device 3, and then the ozone with a certain concentration generated by the ozone generator is added to the raw water through the water injector, and finally the raw water enters the ultraviolet reactor.

[0029] FIG. 2 is a perspective view of the ultraviolet reactor of the invention.

[0030] FIG. 3-FIG. 5 are a front view, a left view and a top view of the ultraviolet reactor of the invention.

[0031] The ultraviolet reactor 3 comprises a cavity 7 and ultraviolet lamps 6.

[0032] Each of the ultraviolet lamp 6 consists of a plurality of ultraviolet lamp tubes 8 which are installed at an angle of 15-30, and a distance d between the lamp tubes meets d=(1/1-UVT)cm.

[0033] Ultraviolet lamp bushings 11 are arranged on the ultraviolet lamp tubes 8, and a number of the ultraviolet lamp tubes 8 depends on power of the ultraviolet lamps, the ultraviolet intensity, the exposure time and the UV dose in to-be-treated water.

[0034] A length-width-height ratio of the cavity 7 is 3:2:1, and 45 baffle plates are arranged at inner corners of the cavity 7, so that stagnant water regions and low-intensity regions are reduced, and the advanced oxidation efficiency is improved. The baffle plates 9 arranged at the opposite corners of the cavity 7 are parallel to the ultraviolet lamp tubes 8, and a length of the baffle plates 9 depends on the dimensions of the reactor.

[0035] The partition plates 10 used for fixing the ultraviolet lamp tubes 8 are arranged in the cavity 7.

[0036] The ultraviolet transmittance is the ratio of non-absorbed ultraviolet to total output ultraviolet after ultraviolet with a wavelength of 254 nm passes through a to-be-treated water sample in a 1 cm cuvette, and can be obtained by measurement and calculation through spectrophotometer.

[0037] Operating principle of the invention is as follows.

[0038] The invention can realize UV/O.sub.3, O.sub.3/H.sub.2O.sub.2 and UV/H.sub.2O.sub.2 advanced oxidation. As for the UV/O.sub.3 process, the following reactions are carried out in the reactor:

O.sub.3+H.sub.2O.fwdarw.H.sub.2O.sub.2

H.sub.2O.sub.2.fwdarw.2.OH

[0039] As for the O.sub.3/H.sub.2O.sub.2 process, the following reactions are carried out in the reactor:

O.sub.3+OH.sup..fwdarw.HO.sub.2.sup.+O.sub.2

H.sub.2O.sub.2+H.sub.2O.fwdarw.HO.sub.2.sup.+H.sub.3O.sup.+

O.sub.3+HO.sub.2.sup..fwdarw..OH+O.sub.2.sup.+O.sub.2

O.sub.3+.OH.fwdarw.HO.sub.2.+O.sub.2

O.sub.3+O.sub.2.sup..fwdarw.O.sub.3.sup.+O.sub.2

O.sub.3.sup.+H.sub.2O.fwdarw..OH+O.sub.2+OH.sup.

[0040] As for the UV/H.sub.2O.sub.2 process, the following reactions are carried out in the reactor:

H.sub.2O.sub.2.fwdarw.2OH.

H.sub.2O.sub.2.fwdarw.HO.sub.2.+H.

H.sub.2O.sub.2+OH..fwdarw.HO.sub.2.+H.sub.2O

H.sub.2O.sub.2+H..fwdarw.OH.+H.sub.2O

HO.sub.2.+H.sub.2O.sub.2.fwdarw.OH.+H.sub.2O+O.sub.2

[0041] The above reactions can be carried out independently or synchronously by starting or stopping corresponding devices; and when all the devices are started, the following reaction is carried out in the reactor:

##STR00002##

[0042] According to the invention, UV/O.sub.3, O.sub.3/H.sub.2O.sub.2 and UV/H.sub.2O.sub.2 advanced oxidation can be carried out independently or synchronously, and the high oxidizability of .OH is fully used, so that the oxidation efficiency is improved, and generation of bromates is avoided. The layout of the ultraviolet lamp tubes and the structure of the reactor are optimized, the ultraviolet radiation effect is brought into full play, and the UV utilization rate is increased. The hydraulic retention time of the reactor is shortened, little space is occupied, and a channel form can be adopted to realize better process cohesion, secondary lifting of the ozone contact tank is avoided, and operation is more economical. The UV dose, the H.sub.2O.sub.2 dose and the O.sub.3 dose can be independently controlled and measured, and the process can be carried out more flexibly.

[0043] The above embodiments are only illustrative ones, and are not all possible ones of the invention. All transformations made within the scope of the invention or its equivalents should also be included in the invention.