A method for advanced treatment of supplementary water for circulating cooling water

Abstract

The invention provides a method for advanced treatment of circulating cooling make-up water. The method comprises the steps of pretreatment and deep purification. Pretreatment comprises the steps of coagulation-filtration and sterilization and algae killing. Deep purification comprises the steps of ion exchange treatment or nanofiltration and ion exchange method combined treatment or membrane distillation method treatment. Sodium hypochlorite, chlorine dioxide and other sterilizing and alga killing agents in an oxidized form or non-oxide form often used in the prior art are replaced with efficient environment-friendly paint capable of preventing microorganism propagation, sterilizing and alga killing effect is good, and low-toxicity or non-toxic substance can be decomposed, degraded or oxidized easily. The method is simple, cost is low, energy efficiency of power equipment can be improved, energy consumption can be reduced, and the service life of equipment can be prolonged.

Description

technical field [0001] The invention relates to the technical field of circulating cooling water treatment, in particular to an advanced treatment method for circulating cooling water make-up water. Background technique [0002] The existing circulating cooling water treatment method is mainly chemical blowdown method, and usually the circulating cooling water should be treated with "three defenses", that is, anti-corrosion, anti-scaling and anti-fouling treatment. The circulating cooling water takes away the heat of the cooling water heated by the low-temperature and low-pressure steam of the steam turbine and the lubricating oil of the steam turbine through the contact with the air in the water tower, convective heat transfer and water evaporation, so as to achieve the purpose of cooling and recycling, in order to prevent water from evaporating After concentration, scaling will form on the heating surface of the cooling equipment, and scale inhibitors need to be added. Com...

AI Technical Summary

Problems solved by technology

Take my country's water price as an example. Before the 1970s, the price of water per cubic meter was only a few cents, but now it has skyrocketed to a few dollars, an increase of tens of times or hundreds of times. Therefore, the original treatment method is no longer economical. In the past ten years, due to restrictions on the exploitation of groundwater, especially the use of groundwater by industrial enterprises, surface water such as river water and reservoir water and urban reclaimed water have been used as replenishment water sources, and the problems of microbial reproduction and biocorrosion have become more prominent. The original treatment methods have been eliminated. Far from meeting the treatment requirements for water quality

Due to design defects (in order to reduce the project cost), the pretreatment of circulating water make-up water (coagulation filtration and sterilization treatment) is very simple, and even directly used as circulating water make-up water without treatment, so that the circulating water is far from meeting the national design specifications Requirements for circulating water quality lead to severe corrosion of equipment and pipelines, which greatly shortens the service life of equipment and greatly increases energy consumption

In order to reduce maintenance costs, most enterprises basically did not implement national design standards, and almost did not carry out anti-corrosion and anti-pollution treatment, resulting in serious corrosion and microbial reproduction problems and energy waste

For example, the large chemical fertilizers introduced in my country in the last century and some electric power companies have the problem of scrapping the cooling equipment within a year or so due to the corrosion of the cooling equipment caused by the microbial reproduction of the circulating cooling water, which greatly shortens the service life of the equipment and affects the safety of the production equipment. Economic Operation

[0004] In recent years, recycling of circulating water and sewage by membrane methods such as reverse osmosis has also been adopted, but it is often not economical, requires large investment, high maintenance costs, and cannot solve the problem of biological corrosion caused by corrosion and biological slime adhesion and heat transfer effects. Bad and wasteful energy problem

There is also electrostatic descaling, but the effect of this process on surface water is very unsatisfactory, and it cannot remove other salts, suspended impurities, colloids, and cannot solve the corrosion problem

In addition, the intermittent addition of bactericidal algicide cannot guarantee that the indicators such as bacteria in the water are always qualified. If the continuous dosing cost will be quite high, the maintenance cost of the enterprise is limited and unaffordable