The invention discloses a double-tank oxidation pond for evaluating catalytic ozonation efficiency, comprising detachable tank bodies made of organic glass, movable ozone aeration pipes and sampling holes. Each tank body has three sections. The height of ozone aeration tube and the number of the holes can be adjusted. The holes are distributed at different positions of the tank bodies for real-time in-situ sampling. It is easy to observe the distribution profile of the gas, liquid and solid phases in the tank bodies. The square double-tank structure is similar to actual production process, and thus the experimental data is easy for computer simulation to enlarge to the actual production process. The size of the ozone aeration pipe and the position of holes in the tank can be adjusted to evaluate the catalytic ozonation effect of sewage treated by different aeration ways and aeration heights.

A preparation method and application of a zero-valent aluminum/iron-bearing clay composite for catalyzing a persulfate to oxidize organics are provided, which belongs to the field of water environmental treatment. A novel catalyst is prepared by an iron-bearing clay and a zero-valent aluminum through a simple ball milling method, for achieving the effect of activating a persulfate to efficiently oxidize and degrade refractory organics in water. The preparation method and operation process thereof are simple. Compared with a chemical synthesis method, the method of the present disclosure brings about less secondary pollution, and has a shorter synthesis time, higher yield and lower cost. The modified material is the natural iron-bearing clay, which is widely available, non-toxic and stable as a heterogeneous catalyst.

The invention relates to a method for treating wastewater in an activated sludge process, which comprises a biological treatment step followed by a sedimentation step for separation of sludge and treated effluent water. The method comprises directing a part of the treated effluent water as a backflow from the sedimentation step to the biological treatment step, the backflow having an original pH value; adjusting the backflow pH from the original pH value to a first pH value between the sedimentation step and the biological treatment step, and adding a coagulant and/or an oxidant to the backflow after the adjustment of the backflow pH to the first pH value and before backflow's entry to the biological treatment step.

The invention relates to a method for treating wastewater in an activated sludge process, which comprises a biological treatment step followed by a sedimentation step for separation of sludge and treated effluent water. The method comprises directing a part of the treated effluent water as a backflow from the sedimentation step to the biological treatment step, the backflow having an original pH value; adjusting the backflow pH from the original pH value to a first pH value between the sedimentation step and the biological treatment step, and adding a coagulant and/or an oxidant to the backflow after the adjustment of the backflow pH to the first pH value and before backflow's entry to the biological treatment step.

A treatment system and method for cephalosporin wastewater are disclosed. The treatment system includes: a flocculation and sedimentation device, an alkali reaction tank, a PAC reaction tank, a PAM reaction tank, a wastewater heat exchanger, a wastewater heater and an oxidation reactor that are connected with each other in sequence, wherein the wastewater heat exchanger is provided with a material inlet, a material outlet, a heat source inlet and a heat source outlet. An oxidized water from the oxidation reactor enters the wastewater heat exchanger from the heat source inlet, the heat source outlet is connected with a product canister, the product canister is connected with a membrane filtration device to realize concentration treatment of a landfill leachate, the material inlet is connected with the PAM reaction tank, and the material outlet is connected with the wastewater heater. An outer side of the oxidation reactor is provided with a micro-interfacial generation system for dispersing and breaking a gas into bubbles. The treatment system of the prevent invention improves the contact of reaction phase interfaces after arranging the micro-interfacial generation system, which ensures a good wastewater treatment effect under relatively mild operating conditions.

Use of Keplerate type polyoxomolybdates of the general structure Mo.sub.72M.sub.30, wherein M is selected from the group consisting of Fe, Cr, V or Mo.sub.2, for decontaminating aqueous media (water) from inorganic and organic pollutants.

A water treatment apparatus includes: a plurality of plate-shaped ground electrodes; a high-voltage electrode unit having counter electrode portions opposing the ground electrodes, support portions supporting the counter electrode portions, and a voltage receiving portion for receiving a high voltage; a water supply unit for supplying to-be-treated water to between the ground electrodes from above, insulating members each having a lower end portion fixed to a support structure fixing lower end portions of the ground electrodes, and an upper end portion connected to the voltage receiving portion of the high-voltage electrode unit. The lower ends of the support portions of the high-voltage electrode unit are held in a space between the ground electrodes, and a portion where each insulating member and the high-voltage electrode unit are connected to each other is located above the water supply unit, so that electric leak due to the to-be-treated water is inhibited.

A ballast water treatment method includes: a step of supplying a sterilizing component to a ballast pipe while taking ballast water into a ballast tank through the ballast pipe; a first measurement step of measuring the concentration of the sterilizing component in the ballast water after the sterilizing component is supplied; a circulation step of returning the ballast water stored in the ballast tank to the ballast pipe through a circulation pipe; a second measurement step of measuring the concentration of the sterilizing component contained in the ballast water returned to the ballast pipe; and a step of supplying the sterilizing component to the ballast pipe 2 when the concentration of the sterilizing component measured in the second measurement step is less than 0.2 times the concentration of the sterilizing component measured in the first measurement step. In the first supply step, the sterilizing component is supplied to the ballast pipe 2 such that the concentration of the sterilizing component measured in the first measurement step becomes 6 mg/L or more.

A ballast water treatment method includes: a step of supplying a sterilizing component to a ballast pipe while taking ballast water into a ballast tank through the ballast pipe; a first measurement step of measuring the concentration of the sterilizing component in the ballast water after the sterilizing component is supplied; a circulation step of returning the ballast water stored in the ballast tank to the ballast pipe through a circulation pipe; a second measurement step of measuring the concentration of the sterilizing component contained in the ballast water returned to the ballast pipe; and a step of supplying the sterilizing component to the ballast pipe 2 when the concentration of the sterilizing component measured in the second measurement step is less than 0.2 times the concentration of the sterilizing component measured in the first measurement step. In the first supply step, the sterilizing component is supplied to the ballast pipe 2 such that the concentration of the sterilizing component measured in the first measurement step becomes 6 mg/L or more.

Various embodiments relate to an acidic ferrate composition and methods of making ferrate. A method of forming ferrate includes treating an iron source with an oxidizer in an aqueous solution having a pH of less than 7 under conditions sufficient to form ferrate.