CN102295318B

CN102295318B - Nanometer rotating disc photocatalytic water treatment device

Info

Publication number: CN102295318B
Application number: CN201110236892A
Authority: CN
Inventors: 周继军; 张雁秋; 刘碧波; 武秀琴; 陈纳; 马梦娟
Original assignee: Henan Institute of Engineering
Current assignee: Henan Institute of Engineering
Priority date: 2011-08-18
Filing date: 2011-08-18
Publication date: 2012-10-03
Anticipated expiration: 2031-08-18
Also published as: CN102295318A

Abstract

The invention relates to a nanometer rotating disc photocatalytic water treatment device which has a large area of mass transfer in gas and liquid phase, a large lighting area, high luminous absorption efficiency, repeatedly usable nano-materials and high photocatalysis efficiency. The invention enables effective solving of problems of high cost and poor effects of treatment of waste water, impossible recovery of powdery nano-materials and poor photocatalysis efficiency of nanometer films existing in the prior art. A technical scheme in the invention for the solving of the problems is as follows: the device comprises a water tank and rotating discs; a plurality of the rotating discs are uniformly arranged on a rotating shaft in the water tank which is coated by a layer of nano-materials; ultraviolet lamps or visible lighting tubes are installed between every two adjacent rotating discs; baffle plates are arranged around the rotating discs and at the upper part of the water tank; one end of the water tank is provided with a waste water inlet while the other end is provided with a sludge outlet; the upper part of baffle plates is provided with an overflow weir; the thickness of the layer of nano-materials is normally in a range of 10 nm to 1 mu m. The invention has the advantages of a unique structure, convenient usage and good treating effects of waste water, and shows innovation to treating devices for waste water.

Description

Nanometer rotating disk photocatalytic water treatment device

Technical field

The present invention relates to water treatment device, especially be applicable to a kind of nanometer rotating disk photocatalytic water treatment device of the wastewater treatment that biochemical is relatively poor.

Background technology

Nano material has good light induced electron-hole to characteristic, and the hole has stronger oxidation capacity, can be with the oxidation operation that is adsorbed in nano-material surface, and also can be with the OH of surface adsorption ^-Oxidation generates OH, simultaneously, and O ²Also can capture the e of nano-material surface ^-Generate O ₂ ^-，O ₂ ^。-With H ₂O and OH ^-The chemical reaction of a series of complicacies takes place; Also can generate OH, and the OH extremely strong radical that is oxidation capacity, almost can be with all oxidation operations in the water; Produce carbonic acid gas, water and inorganic salt; In addition, a lot of nanometers also have inexpensive, stable and eco-friendly characteristics, will play an important role in water treatment field.

The biodegradability of a lot of trade effluents is relatively poor; Like dyeing waste water, antibiotic waste water, agricultural chemicals waste water etc.; And to this type of wastewater treatment, many both at home and abroad at present is main with biochemical process, is aided with chemical method; But ubiquity is handled shortcomings such as investment cost is big, running cost is high, treatment effect is not good, is badly in need of new technology and method it is handled.

The nano-photo catalytic water technology has a good application prospect, and its advantage is: (1) degradation speed is fast, generally only needs dozens of minutes can obtain good water treatment effect to several hrs; (2) degraded non-selectivity, any organism of almost degrading is particularly suitable for chlorinatedorganic, polycyclic aromatic hydrocarbons etc.; (3) oxidation reaction condition is gentle, less investment, and energy consumption is low, with under UV-irradiation or the sunlight photocatalysis oxidation reaction taking place; (4) non-secondary pollution, organism thoroughly are degraded to CO ₂And H ₂O; (5) applied range, nearly all sewage and waste water can adopt.

At present, nano powder photocatalyst agent preparation technology is comparatively ripe, and the photocatalytic degradation effect is also relatively good.

Yet Powdered nano-photocatalyst in use exists dispersion and recovery difficulty, can't reuse and, absorptivity not high a series of problems strong to scattering of light, even has the potentially dangerous of nano-powder pollution.This also is the major cause that is difficult to large-scale application and commercialization popularization with the photocatalysis technology that the nano powder photocatalyst agent is the basis.

Since the nineties in 20th century, states such as the U.S., Japan have carried out the research of nanometer powder immobilization or nano thin-film preparation.Up to the present, test the feasibility of multiple film preparing technology, and in various organic photocatalytic degradation researchs, obtained certain effect.Nano-film photocatalyst is compared with nanometer powder to have and is not had the advantage of separating, can reuse; But photocatalysis efficiency is compared the reduction that all has in various degree with nanometer powder; This is because the fixing back of catalyzer specific surface area reduces; Cause its adsorption and utilization ratio to reduce, thereby reduced the activity of nano-photocatalyst.

Summary of the invention

To above-mentioned situation; For overcoming the defective of prior art; The present invention's purpose just provides a kind of nanometer rotating disk photocatalytic water treatment device that gas-liquid phase mass transfer area is big, illuminating area is big, efficiency of light absorption is high, nano material is reusable and photocatalysis efficiency is high, can effectively solve the problem of the high and weak effect of existing wastewater treatment expense and the powder nanometer material can't reclaim and the problem of nano thin-film photocatalysis efficiency difference.

The technical scheme of its solution is, comprises tank and rotating disk, all is equipped with a plurality of rotating disks on the rotation axis in the tank; Be coated with layer of nanomaterial on the rotating disk, uv lamp or visible fluorescent tube are housed between two adjacent rotating disks, in the tank upper end baffle plate is housed around the rotating disk; Tank one end has the waste water import; The other end has sludge outlet, and there is overflow weir the baffle plate upper end, and said nano material layer thickness is generally between the 10nm-1 μ m.

Structure of the present invention is unique, easy to use, and good waste water treatment effect is the innovation on the wastewater treatment equipment.

Description of drawings

Fig. 1 is a three-dimensional structure diagram of the present invention.

Fig. 2 takes away the three-dimensional structure diagram of ceiling for the present invention.

Fig. 3 takes away the left view of ceiling and baffle plate for the present invention.

Fig. 4 takes away the front view of ceiling and baffle plate for the present invention.

Embodiment

Do further explain below in conjunction with the accompanying drawing specific embodiments of the invention.

Provide by Fig. 1 to Fig. 4, the present invention includes tank and rotating disk, all be equipped with a plurality of rotating disks 3 on the rotation axis 2 in the tank 1; Be coated with layer of nanomaterial on the rotating disk 3, uv lamp or visible fluorescent tube 4 (confirming according to the nano material band-gap energy) are housed between two adjacent rotating disks 3, in tank 1 upper end baffle plate 5 is housed around the rotating disk 3; Tank 1 one ends have waste water import 6; The other end has sludge outlet 7, and there is overflow weir 12 baffle plate 5 upper ends, and said nano material layer thickness is generally between the 10nm-1 μ m.

In order to guarantee result of use; The thickness of said rotating disk 3 is generally the 2-6 millimeter, and diameter is 30-300 centimetre (confirming according to wastewater flow), and two adjacent rotating disk spacings are about 20-30 centimetre; The lower edge of rotating disk 3 is 0.5-3 centimetre apart from tank 1 distance from bottom, and rotating disk 3 rotating speeds are that 2-3 changes /Minute, its material is for having certain intensity and toughness, and corrosion-resistant material processes, and when rotating disk 3 diameters are big, adorns a plurality of uv lamps or visible fluorescent tube between two adjacent rotating disks.

Said baffle plate 5 is skewed, and there is vertical packaged type ceiling 8 its upper end, when the wind and rain sky; Can avoid rotating disk 3 and fluorescent tube 4 to be blown and beaten, at fine day, when wind speed is moderate by dust storm and rainwater; But Xiang Yiduan removes ceiling 8; Make full use of sunshine, when removing ceiling 8, the baffle plate 5 of inclination can increase the area of solar radiation rotating disk 3.

Said uv lamp or visible fluorescent tube 4 are the long fluorescent tube of circular arc, are fixed between the rotating disk 3 through the support on the baffle plate 59, and the supply lead of uv lamp or visible fluorescent tube 4 places in the supply lead fixed tube 10 in baffle plate 5 outsides, and links to each other with power supply.

Said tank 1 is semicircle hollow body, and sludge outlet 7 places semicircular base, links to each other with tank 1 through sludge bucket 11, is convenient to the sedimentary discharge in the waste water.

Layer of nanomaterial of the present invention prepares nanoparticle through methods such as sol-gel method, sol method, hydrothermal methods; Mode through rotation or dip-coating; Nano sol or gel are coated in disc surfaces equably; Heating at high temperature can obtain nanocrystal, and crystal combines closely with disc surfaces again.Some nanoparticle that utilizes aforesaid method to obtain utilizes methods such as hydrothermal method again, can the production nanometer rod, nano wire (like ZnO), add specific ionogen, can also produce nanotube.

In addition, can also be through utilizing direct oxidation method or anonizing (like TiO ₂), can then mf be covered disc surfaces becoming nano material on the mf surface; Also can utilize galvanic deposit/alumina formwork method; Can generate nanometer rod, nanotube, nano wire, the nano belt of various semiconductor materials on the mf surface; Can improve the specific surface area of nanometer greatly; Thereby improve its catalytic performance, the mf film covers disc surfaces then, processes the nano material rotating disk.

The layer of nanomaterial of indication of the present invention comprises that all can be used for light-catalysed semiconductor nano material, like MOX TiO ₂, ZnO, SnO ₄, ZrO ₂, Cu ₂O, Ce ₂O, W ₂O ₃Deng, metallic sulfide CdS, PbS, Ag ₂S, Sb ₂S ₃, ZnS, Bi ₂S ₃Deng, also comprise the complex metal oxides conductor material, like BiVO ₄Deng.

Above-mentioned nano material; Like band-gap energy big (greater than 3.0eV),, its band gap is narrowed down through methods such as doping metals or non-metallic element, narrow gap semiconductor sensitization, noble metal nano particles sensitization, the sensitizations of organo-metallic pigment; Absorption spectrum (can not only utilize UV-light to the visible light expansion; Sunshine also capable of using), and can prolong the right RT in light induced electron-hole, thereby improve its catalytic performance greatly.

Service condition of the present invention is that waste water under the rotation of rotating disk 3, forms the thin moisture film of one deck and attaches after waste water import 6 gets into tank 1 on the nanometer layer on the rotating disk 3; Because rotating disk quantity (at a distance of about 20-30cm) is more, has improved illuminating area greatly, accelerates light-catalyzed reaction speed; So simultaneously, the directly water transmission in tank of airborne oxygen, and moisture film transmission that can also be on rotating disk; Improve the gas-liquid phase mass transfer area of oxygen greatly, because moisture film is thinner, significantly reduced the resistance of liquid mass transfer of oxygen simultaneously; Thereby improved the speed that oxygen transmits greatly in water, also reduced reflection and the sorption of water greatly, improved efficiency of light absorption light; Thereby greatly improve light-catalyzed reaction speed, the waste water after the processing is drained through overflow weir 12, and mud is discharged through sludge outlet 7.

Structure of the present invention is unique, easy to use, good waste water treatment effect, and cost is low, is the innovation on the relatively poor sewage treatment equipment of biochemical.

Claims

1. a nanometer rotating disk photocatalytic water treatment device comprises tank and rotating disk, it is characterized in that; All be equipped with a plurality of rotating disks (3) on the rotation axis (2) in the tank (1); Rotating disk is coated with layer of nanomaterial on (3), and uv lamp or visible fluorescent tube (4) are housed between adjacent two rotating disks (3), in tank (1) upper end baffle plate (5) is housed around the rotating disk (3); Tank (1) one end has waste water import (6); The other end has sludge outlet (7), and it is between the 10nm-1 μ m that there are overflow weir (12), said nano material layer thickness in baffle plate (5) upper end;

The thickness of said rotating disk (3) is the 2-6 millimeter, and diameter is 30-300 centimetre, and two adjacent rotating disk spacings are 20-30 centimetre, and the lower edge of rotating disk (3) is 0.5-3 centimetre apart from tank (1) distance from bottom, and rotating disk (3) rotating speed is that 2-3 changes /Minute, when rotating disk (3) when diameter is big, adorn a plurality of uv lamps or visible fluorescent tube between two adjacent rotating disks;

Said uv lamp or visible fluorescent tube (4) are the long fluorescent tube of circular arc; Be fixed between the rotating disk (3) through the support (9) on the baffle plate (5); The supply lead of uv lamp or visible fluorescent tube (4) places in the supply lead fixed tube (10) in baffle plate (5) outside, and links to each other with power supply.

2. nanometer rotating disk photocatalytic water treatment device according to claim 1 is characterized in that said baffle plate (5) is skewed, and there is vertical packaged type ceiling (8) its upper end.

3. nanometer rotating disk photocatalytic water treatment device according to claim 1 is characterized in that said tank (1) is semicircle hollow body, and sludge outlet (7) places semicircular base, links to each other with tank (1) through sludge bucket (11).