Ammonium recovery and zero discharge technology and system of alumite-titanium wastewater

Abstract

The invention provides a vanadium titanium wastewater ammonium recycling and zero emission technique which is characterized by comprising a precipitation process, an ammonia removal process, a vapor condensation process and a COD (chemical oxygen demand) removal process. Plastic mass and suspended solid in wastewater are condensed, precipitated and then removed under the actions of coagulants and flocculating agents in the precipitation process, ammonia in the wastewater is removed under the action of chemical extraction in the ammonia removal process, moisture in the wastewater is evaporated and condensed, heavy metals and salinity in the wastewater are removed in the vapor condensation process, and COD in the wastewater is removed under a water treatment technique combining an activated sludge method and a membrane separation technique in the COD removal process. According to the method, wastewater can be treated and recycled, ammonium chloride used by a manufacture procedure can be acquired, and zero emission is achieved.

Description

technical field [0001] The invention relates to the field of water treatment equipment, in particular to an ammonium recovery and zero discharge technology of alum-titanium wastewater and a system to which the technology can be applied. Background technique [0002] Alumite wastewater is mainly produced in the alum extraction process of alumite magnetite. The main characteristics of wastewater include high ammonia nitrogen, high heavy metals, and high salt. Due to the high salinity of wastewater, and high salinity can inhibit the growth and reproduction of microorganisms, the application of direct biological treatment is rarely used, and it is basically excluded from the conventional treatment process. At present, the more commonly used treatment methods are the combination of secondary or tertiary processes of the following processes: [0003] Chemical precipitation method: By adding a precipitant to the wastewater, the precipitant and heavy metal ions form precipitation ...

AI Technical Summary

Problems solved by technology

Main disadvantages: A large amount of sediment is produced, and the sediment is transported to qualified units as hazardous waste, which is expensive and limited by the processing capacity of a third-party qualified treatment unit

Main disadvantages: The adsorption equilibrium time is long, the processing efficiency is low, and it often takes several hours to have a better adsorption effect

Main disadvantages: It is greatly affected by environmental factors (temperature, pH, gas-liquid ratio, oily substances, surfactants), it needs external steam to have a better blow-off effect, and the power consumption is large

Main disadvantages: need to add a large amount of phosphate and magnesium salt agents, and the control conditions for the precipitation of magnesium ammonium phosphate are harsh, resulting in a large amount of precipitation, which cannot realize the recovery and utilization of ammonia

Main disadvantages: high requirements for wastewater pretreatment before entering the membrane, high high pressure, high technical requirements, and low freshwater yield

Main disadvantages: the conventional evaporation method directly uses electric heating or steam as energy, which has high energy consumption, and because the wastewater often contains high chloride ions, the equipment is easy to corrode and difficult to maintain

However, due to a certain amount of volatile organic substances in the evaporation process, there are still certain COD substances in the evaporated wastewater.

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