Electrocatalytic oxidation treatment equipment

1, Summary

Wastewater treatment of electrocatalytic oxidation has certain advantages, such as rapid reaction, high decolorizing rate, few sludge, manage conveniently, easy to autocontrol, etc. Under the electrochemistry, it can change the physical and chemical property of the sewage, transform the organic matters into CO₂ and water to make the wastewater hazard-free, and control by adjusting the pressure and electric current to ensure the production water stable while the pollutant concentration in raw water changes. Compare with other treatment methods, it has the merits of short-time treatment, small cubage, small area occupancy. Traditional electroanalysis method uses low voltage-high-current circuit. It can’t be widely applied to industry because of the defects as high power consumption, large consumption for electrode materials. Electrocatalytic oxidation treatment equipment is a kind of equipment for treating dyeing and printing wastewater as well as dye production wastewater, which was researched and developed by our company. Recent years, it has brought huge environmental and economical benefits after being adopted for dying and printing wastewater treatment.

Electrocatalytic oxidation equipment adopts advanced rectangle pulse power source circuit to make up for the defect of low power exist in cosine pulse circuit to make the current distributng format more perfect. Compare with traditional electrolytic method, it not only can save 30% power and reduce 20% polar plates consumption, but also has higher removal efficiency.

Currently, this electrocatalytic oxidation treatment equipment is the ideal equipment for wastewater treatment of textile dying and printing, dye production industries.

2, Usage and characteristic

Electrocatalytic oxidation treatment equipment uses the high pulse voltage added in the anode and cathode of electrobath to make wastewater electrolyse to produce activated hydrogen. There will be a strong absorption while the active gas and polar plates dissolve in the wastewater and some nascent hydroxide flocs form. Then, a range of reactions such as oxidatuin,reduction, absorption, aggregation happen. It is a prefessional equipment for wastewater purification which applys to the wastewater treatment of dying and printing, dye chemistry, hospital, leather, plating, etc., with the advantages of advanced technic, resonable design,small investment, good treatment effect, low operation charge, being easy to maintain.

The equipment has its special circuit format without the disadvantage of low power which exist in the cosine pulse circuit. The high voltage cosine electric flocculation equipment will change the cosine pulse to DC when the voltage is 300V. But this equipment will remain the break make ratio of rectangle pulse adjestable continuously when the voltage is 300V.

The electrobath polar plates are distributed in series format to reduce the influence for pulse waveform when capacitance charge and discharge to improve the power utilization ratio and achieve the purpose of low power consumption, low iron consumption and high purification efficiency. The polar plates use many kinds of materials with solubility or insolubility, this invoid the disadvantage of treated water yellowing which is caused by high voltage pulse electric flocculation equipment adopting iron plates as electrode materials only.

The water through the reaction of corrugated plate reactor can make floc increasing, it is easy to separate the solid and liquid. The equipment adopts the most advanced settler in the world with cocurrent and countercurrent to improve the settling efficiency. The treated water from the settler can be discharged after prefiltration and fine filtration.

3, Principle

The equipment includes electric control box, electric flocculation tank and settler, as well as water pump as an assistant element.

It depends on the added power current which can be commutated to be DC, then to be changed into continuously frequency-modulated high voltage rectangle pulse current input through pulse circuit. And wastewater are electrolysed in the electrobath, with some electrochemical reactions around electrode plate. The functions are as follows:

⑴ Electrochemical reactions around plate make wastewater to be electrolysed into active hydrogen and active oxygen with strong redoxomorphism. Active hydrogen can decolor the coloring matter with oxidation state in the wastewater through reduction reaction. And active oxygen can transform the organic matters into CO₂ and water to be harmless through oxygenolysis of the dissolved organic matters in the wastewater.

⑵ Parts of polar plates dissolved in the water to form nascent state hydroxide flocs under the function of current.The flocs have very strong absorption, such as absorbing undissolved pollutant and colloid in the wastewater to purify the water.

⑶ H₂ and O₂ which are transformed from active hydrogen and active oxygen separately through chemical reaction can escape with imperceptible bubbles in the wastewater, and reach the water purification effect through attaching to the surface of dissolved matters.

The equipment achieves versetility with oxidation, deoxidation, flotation, settlement, filtration, and gets the superior technical index like small occupancy, high efficiency, low cost.  

4, Main technical index:

⑴ Purification capacity

Raw water: PH 5-7, CODcr<1200mg/L, sulphide<50mg/L

Chroma<4000 times, BOD5<300mg/L, Cr+6<50mg/L

Treated water conform to the standard for discharge, clean and nearly no color, with the chroma removing rate of more than 95%.

⑵ Average iron consumption: 20g per ton wastewater.

⑶ Average power consumption:

Raw water CODcr< 500mg/L, power consumption<0.5kwh per ton wastewater

Raw water CODcr< 500～1000mg/L, power consumption<1.0kwh per ton wastewater

Raw water CODcr< 1000～3000mg/L, power consumption<1.5kwh per ton wastewater

Lifting pump power consumption 0.08～1.0kwh per ton wastewater

⑷ Temperature 0-45℃

5, Specification

See sheet 1

Sheet 1

6, Equipment installation instruction

See fig 2, sheet 2 and sheet 3

Equipment inlet and outlet pipes sheet              (mm)           sheet 2

Equipment size(mm)                      Sheet 2

7, Attentions and maintain points

⑴ Must connect ground wire safely to ensure the workers’ safety when use this equipment, and the resister should be <1Ω.

⑵ In the pipes installation process, inlet and outlet pipes, drain pipes for eletrobath must be unplasticized poly vinyl chloride pipes (UPVC), while inlet and outlet pipes, drain pipes for settler can be galvanized pipes.

⑶ Flowmeter. There must be ground wire for water pump to avoid static in sullage.

⑷ Maintain points see sheet 4

Troubles and maintain       Sheet 4