Bioelectrochemistry sewage nitrogen and phosphorus recovery with synchronization of carbon fixing and hydrogen producing system and method

Abstract

Bioelectrochemistry sewage nitrogen and phosphorus recovery with synchronization of carbon fixing and hydrogen producing system and method. The system includes a bio-anode chamber, an acid producing chamber, a desalting chamber, a cathode chamber, and an absorption chamber, which are successively separated by a bipolar membrane, an anion exchange membrane, a kation exchange membrane, and a gas-permeating hydrophobic membrane, wherein the acid producing chamber is connected to the absorption chamber through two tubes with pumps, so that acid liquid circularly flows between the two chamber. Under an external voltage, the bio-anode can degrade organic substances in sewage to generate electrons, H+ and CO2, wherein the electrons arrive at the cathode through an external circuit and the CO2 isfixed by lime water; the bipolar membrane produces OH- which enters the anode chamber to be reacted with the H+ so as to keep a neutral condition. The H+ produced by the bipolar membrane enters the acid producing chamber; the desalting chamber supplies acid radicals and kations for producing acid and alkali; the cathode chamber receives the electrons and produces H2 and OH-, wherein the OH- can increase the pH of the sewage to provide an alkaline environment for recovery of PO4<3->, and promote the conversion of NH4+ to NH3, which is then escaped. The acid solution in the acid producing chamber flows to the absorption chamber for adsorbing the NH3 which permeates through the gas-permeating hydrophobic membrane, thus synchronously purifying H2. The system and method achieve the simultaneousrecovery of N and P in sewage, synchronously fix carbon and produce the byproducts CaCO3 and H2.

Description

Technical field [0001] The invention belongs to the technical field of sewage treatment and resource recovery in environmental engineering, and specifically relates to a biological electrochemical recovery sewage nitrogen and phosphorus synchronous carbon fixation hydrogen production system and method. Background technique [0002] Sewage such as urine, manure fermentation broth, sludge fermentation broth, aquaculture fermentation broth, landfill leachate, garbage incineration plant leachate, organic wastewater fermentation broth, organic waste fermentation broth, etc. contain relatively high concentrations of organic matter , Ammonium nitrogen and phosphate, if these wastewater is directly discharged, it will cause environmental pollution, causing natural water bodies to become black and odorous or eutrophication. The existing treatment methods of this type of sewage mainly include biological method, struvite method, stripping-absorption method to recover ammonium nitrogen and h...

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Problems solved by technology

[0003] Aiming at the problem of large acid-base consumption in the treatment of sewage containing high concentrations of carbon, nitrogen and phosphorus in the prior art, the primary purpose of the present invention is to provide a system and method for electrochemical recovery of nitrogen and phosphorus from sewage and synchronous carbon fixation and hydrogen production

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