Novel treatment system for ammonia-containing wastewater of nuclear power plant

Abstract

The utility model relates to a novel treatment system for ammonia-containing wastewater of a nuclear power plant. The novel treatment system comprises a booster pump, an automatic flushing filter, a seawater electrolytic bath, a seawater storage tank, a chlorination pump and a reaction tank which are connected in sequence, the aeration fan and the aeration device are connected, the aeration fan is arranged outside the reaction tank, and the aeration device is arranged inside the reaction tank; the two ends of the wastewater reflux pump are connected with the reaction tank, and the wastewater reflux pump is arranged outside the reaction tank. Compared with the existing technology for removing ammonia nitrogen by purchasing sodium hypochlorite, the device has the characteristics that the operation cost is low, the dosing cost is about 30% of that of the prior art, compared with the biological method and gaseous membrane method ammonia removal process, the sludge and the byproducts are not generated, the treatment problem of the sludge and the byproducts is solved, the water quality of the produced water is good, and the production cost is low. The ammonia nitrogen can be reduced to below 5mg / L, and the limitation on the ammonia nitrogen in the emission standard is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of wastewater treatment, and in particular relates to a new treatment system for ammonia-containing wastewater in a nuclear power plant. Background Art

[0002] At present, the resin regeneration wastewater of the condensate polishing system of nuclear power plants contains a large amount of ammonia nitrogen, with ammonia nitrogen content between 200mg / L and 1000mg / L, which does not meet the environmental emission standards and needs to be treated. Common ammonia nitrogen treatment processes include adding purchased sodium hypochlorite to remove ammonia nitrogen, biological ammonia removal, gas membrane ammonia removal, etc., as follows:

[0003] 1. Purchasing sodium hypochlorite to remove ammonia nitrogen adopts the principle of breakpoint chlorination to oxidize NH3-N into N2. When adding purchased sodium hypochlorite (10% effective chlorine) to remove ammonia nitrogen, the cost of adding medicine is very high. When the ammonia content is high, the cost of adding medicine per ton of water is more than 50 yuan. The breakpoint chlorination method is specifically a chemical denitrification process in which chlorine gas or sodium hypochlorite is introduced into the wastewater to use effective chlorine to oxidize NH3-N in the wastewater into N2. When the effective chlorine is introduced into the wastewater to a certain point, the free chlorine content in the water is the lowest, and the ammonia concentration drops to zero. When the amount of effective chlorine introduced exceeds this point, the free chlorine in the water will increase. This point is called the breakpoint, and the chlorination under this state is called the breakpoint chlorination;

[0004] 2. There are many types of biological ammonia removal processes, among which the most economical is the "anaerobic ammonium oxidation + A / O" combined process, which is difficult to operate and control, and will produce sludge. Since the regeneration wastewater of condensate polishing treatment in nuclear power plants may be contaminated by radioactivity, the final disposal of sludge is difficult;

[0005] 3. The gaseous membrane method of ammonia removal uses a microporous hydrophobic membrane to separate the ammonia-containing wastewater and the absorption liquid, and uses the vapor pressure difference of the volatile component (ammonia) on both sides of the membrane as the driving force to remove, recover, and enrich ammonia in the feed liquid or wastewater. A large amount of ammonium salt solution will be produced, which is difficult to handle.

[0006] The above treatment processes have the problems of high operating costs and difficulty in disposing of sludge and by-products. Utility Model Content

[0007] In order to solve the technical problems existing in the prior art, the utility model provides a novel treatment system for ammonia-containing wastewater in a nuclear power plant.

[0008] The technical solution of the utility model is to provide a novel treatment system for ammonia-containing wastewater in a nuclear power plant, comprising a booster pump, an automatic flushing filter, a seawater electrolyzer, a seawater storage tank, a chlorination pump and a reaction tank connected in sequence; an aeration fan and an aeration device connected and arranged, the aeration fan is arranged outside the reaction tank, and the aeration device is arranged inside the reaction tank; and a wastewater reflux pump, both ends of the wastewater reflux pump are connected to the reaction tank and arranged outside the reaction tank.

[0009] Compared with the prior art, the novel treatment system for ammonia-containing wastewater in nuclear power plants provided by the utility model has the following beneficial effects:

[0010] The seawater is lifted by a booster pump to an automatic flushing filter to remove large suspended particles in the seawater, and then enters the electrolytic cell to produce effective chlorine through electrochemical reaction. The seawater containing effective chlorine is collected in a storage tank and then transported to the reaction tank through a chlorination pump for aeration and wastewater circulation until the ammonia nitrogen content reaches the standard and is discharged.

[0011] The utility model uses seawater containing effective chlorine produced by a seawater electrolyzer to remove ammonia nitrogen in wastewater. Effective chlorine reacts with ammonia nitrogen in wastewater to decompose and generate nitrogen gas, so as to achieve the purpose of removing ammonia nitrogen without generating sludge and by-products. Compared with the existing technology of removing ammonia nitrogen with purchased sodium hypochlorite, the operation cost is low, and the dosing cost is about 30% of the existing technology. Compared with the biological method and gas membrane method of ammonia removal, no sludge and by-products are generated, which solves the problem of disposing sludge and by-products. The produced water has good water quality, and the ammonia nitrogen can be reduced to below 5mg / L, meeting the restrictions on ammonia nitrogen in the emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of an embodiment of the system of the utility model. DETAILED DESCRIPTION

[0013] The specific implementation of the present utility model is described in detail below in conjunction with specific embodiments.

[0014] Provided is a novel treatment system for ammonia-containing wastewater in a nuclear power plant, comprising a booster pump 101, an automatic flushing filter 102, a seawater electrolyzer 103, a seawater storage tank 104, a chlorination pump 105 and a reaction tank 106 connected in sequence, wherein the booster pump 101 is used to lift seawater, the automatic flushing filter 102 removes large suspended particles in the seawater, the seawater electrolyzer 103 generates effective chlorine through an electrochemical reaction, and product water is collected in a seawater storage tank 104 containing effective chlorine, and then transported to the reaction tank 106 through the chlorination pump 105. The system also includes an aeration fan 107 and an aeration device 108 connected and arranged. The aeration fan 107 is arranged outside the reaction tank 106, and the aeration device 108 is arranged inside the reaction tank 106. The aeration device 108 and the wastewater circulation ensure that the effective chlorine and the wastewater are mixed evenly. The effective chlorine reacts with the ammonia nitrogen in the wastewater to decompose and generate nitrogen. In addition, by inputting an appropriate amount of air or oxygen into the wastewater, it has the function of mixing and stirring, which can promote the uniform mixing and contact of pollutants in the wastewater, make the material distribution in the wastewater more uniform, and improve the treatment effect. The system also includes a wastewater reflux pump 109, both ends of the wastewater reflux pump 109 are connected to the reaction tank 106, and the wastewater reflux pump 109 reacts with the ammonia nitrogen in the wastewater to decompose and generate nitrogen until the ammonia nitrogen content reaches the standard and is discharged. The system also includes supporting pipeline valves, instruments and control systems.

[0015] The working principle of this system is that seawater is lifted by a booster pump 101 to an automatic flushing filter 102 to remove large suspended solids in the seawater, and then enters the electrolytic cell to produce effective chlorine through an electrochemical reaction. The seawater containing effective chlorine is collected in a seawater storage tank 104, and then transported to a reaction tank 106 through a chlorination pump 105 for aeration and wastewater circulation until the ammonia nitrogen content reaches the standard and is discharged.

[0016] Compared with the existing technology of removing ammonia nitrogen by purchasing sodium hypochlorite, this system has low operating costs, and the cost of adding medicine is about 30% of the existing technology. Compared with the biological method and gas membrane ammonia removal process, no sludge and by-products are produced, which solves the disposal problem of sludge and by-products. The produced water quality is good, and the ammonia nitrogen can be reduced to below 5mg / L, meeting the restrictions on ammonia nitrogen in the emission standards.

Claims

1. A novel treatment system for ammonia-containing wastewater in a nuclear power plant, characterized in that: It includes a booster pump, an automatic flushing filter, a seawater electrolyzer, a seawater storage tank, a chlorination pump and a reaction tank connected in sequence; An aeration fan and an aeration device are connected and arranged, wherein the aeration fan is arranged outside the reaction tank, and the aeration device is arranged inside the reaction tank; as well as A wastewater reflux pump, both ends of which are connected to the reaction tank and are arranged outside the reaction tank.

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