CN102887606A - Garbage leachate treatment method using direct current flocculation-MBR (membrane bioreactor) - Google Patents

Abstract

A direct current electrocoagulation-MBR method for treating landfill leachate, the main process of which is the electrocoagulation-chemical oxidation-MBR process, and the method flow sequentially includes an adjustment tank, an electrocoagulation reactor, a chemical oxidation tank, an anoxic tank, and a membrane biological reaction appliances, and clear water pools. The method of the invention has the advantage of integrated and simultaneous removal of heavy metals and organic matter.

Description

A method of DC electrocoagulation-MBR for treating landfill leachate

technical field

The invention belongs to the field of water treatment methods, and relates to a direct current electrocoagulation-MBR method for treating landfill leachate.

Background technique

Landfill leachate refers to the moisture contained in the garbage itself in the landfill, the rain and snow water and other moisture entering the landfill, deducting the saturated water holding capacity of the garbage and the covering soil, and passing through the garbage layer and the covering soil. A high concentration wastewater. Landfill leachate generally contains a large amount of heavy metal ions and high COD content, so it is relatively difficult to treat.

The reaction principle of electroflocculation is to use metals such as aluminum and iron as the anode. Under the action of direct current, the anode is eroded to produce Al and Fe plasma. After a series of hydrolysis, polymerization and oxidation of ferrous iron, it develops into various hydroxyl complexes. Compounds, polynuclear hydroxyl complexes and even hydroxides, so that the colloidal impurities and suspended impurities in the wastewater coagulate and precipitate and separate. At the same time, the charged pollutant particles swim in the electric field, and part of their charges are neutralized by the electrodes to promote It destabilizes and gathers.

Membrane Bioreactor (MBR for short) is a new type of high-efficiency sewage treatment and reuse process that organically combines membrane separation technology with traditional sewage biological treatment processes. In recent years, it has received increasing attention in the field of international water treatment technology. The membrane separation equipment is placed in the reactor, and the membrane is used to filter the muddy sewage in the biochemical reaction tank, which can intercept the activated sludge and macromolecular organic substances, realize the separation of mud and water, and at the same time make the concentration of activated sludge in the reactor larger Improve, thereby greatly improving the degradation efficiency of biochemical reactions. The high efficiency and high-quality effluent obtained by the organic combination of the two technologies of membrane separation and biochemical treatment have made the membrane bioreactor one of the world's advanced and most promising new technologies for wastewater treatment. .

Contents of the invention

The purpose of the present invention is to provide a direct current electrocoagulation-MBR method for treating landfill leachate. The invention combines the electrocoagulation technology with the membrane bioreactor method, and is used for the treatment of landfill leachate. The invention adopts direct current electric flocculation-MBR main process to construct: adjustment pool, electric flocculation reaction, chemical oxidation pool, anoxic pool, membrane bioreactor and clear water pool.

The present invention is realized through the following technical solutions:

The landfill leachate flows through the adjustment tank, the electrocoagulation reactor, the chemical oxidation tank, the anoxic tank, the membrane bioreactor in sequence with a certain hydraulic retention time, and finally passes through the clear water tank before being discharged. The electrocoagulation reactor is composed of aluminum or iron electrode plates and a DC output power supply; the membrane bioreactor includes built-in membrane modules and jet aeration devices; the chemical oxidation tank is fed with sodium hypochlorite as a strong oxidant.

Method of the present invention comprises the following steps:

1. The landfill leachate enters the electroflocculation reactor after being regulated by the regulating tank. Under the action of direct current, the reactor plate undergoes electrolysis, and the electrolytic ions (such as aluminum ions) produced undergo flocculation and precipitation reactions with heavy metal ions, making the influent Heavy metal ions are removed.

2. After the leachate flows into the chemical oxidation tank, the refractory organic matter is oxidized by sodium hypochlorite into easily degradable small molecules, and a reduction reaction (such as denitrification reaction) occurs in the anoxic tank, further replacing C, N and other elements into low-valent states .

3. Enter the membrane bioreactor to undergo biological aerobic degradation, and remove the organic matter; the air flotation generated by aeration also makes the refractory organic matter float on the upper water surface.

4. After standing still in the clear water pool for a period of time, check the various pollution indicators, and discharge or reuse after reaching the corresponding standards.

The present invention is implemented according to the above method to achieve the purpose of treating landfill leachate.

specific example

Specific examples are omitted.

Claims (2)

1. the method for a direct current flocculation-MBR treating refuse percolate, present method combines electric flocculation technique and membrane bioreactor method, is used for the processing of percolate; Method adopts direct current flocculation-MBR main process to construct to be equalizing tank, electric flocculation reaction, chemical oxidation pond, anoxic pond, membrane bioreactor and clean water basin.

2. the method for claim 1 is characterized in that percolate is with certain hydraulic detention time flow through successively equalizing tank, electric flocculation reactor, chemical oxidation pond, anoxic pond, membrane bioreactor, finally by water outlet behind the clean water basin; The electricity flocculation reactor is comprised of aluminium or ferroelectric pole plate and dc output power; Membrane bioreactor comprises built-in membrane module and efflux aerator; Chemical oxidation pond adds clorox as strong oxidizer.