Patent ID: 7914677

Claim:
A water treatment apparatus comprising: a membrane device ( 21 ) that treats introduced water by means of a membrane; and a pretreatment device that carries out pretreatment of water to be introduced into the membrane device ( 21 ); wherein the pretreatment device comprises: a raw water tank ( 1 ) which is filled with polyvinylidene chloride filler ( 3 ) and into which water is introduced from outside; a micro-nano bubble generation tank ( 6 ) which has a micro-nano bubble generator ( 7 ) that generates micro-nano bubbles including both of micro bubbles and nano bubbles and makes the water introduced from the raw water tank ( 1 ) contain the micro-nano bubbles, the bubble generation tank ( 6 ) coupled to a micro-nano bubble generation aid-containing tank ( 19 ) so as to add aid material to generated bubbles ( 18 ); a water returning device ( 5 ) that sends part of the water in the micro-nano bubble generation tank ( 6 ) back to the raw water tank ( 1 ) so as to propagate microorganisms activated by the micro-nano bubbles in the polyvinylidene chloride filler ( 3 ) in the raw water tank ( 1 ), and attach the micro-nano bubbles to the polyvinylidene chloride filler ( 3 ); and a charcoal water tank ( 11 ) which has an agitating device and is filled with a charcoal ( 15 ) or a synthetic charcoal such that physical adsorption of organic matters and biological decomposition of the adsorbed organic matters are linked together, wherein the micro-nano bubbles contained in the water introduced from the micro-nano bubble generation tank ( 6 ) are attached to the microorganisms propagating in the charcoal ( 15 ) or the synthetic charcoal to activate the microorganisms such that the activated microorganisms effectively treat the organic matters in the introduced water through decomposition to prevent clogging phenomenon of the membrane in the membrane device ( 21 ) located in a subsequent stage, wherein the clogging of the membrane in the membrane device ( 21 ) is prevented by the micro-nano bubbles staying in the water to be treated from the charcoal water tank ( 11 ).