A papermaking wastewater advanced treatment system and process

Abstract

The invention discloses a papermaking wastewater advanced treatment system and its technology, wherein the bactericide dosing device in the papermaking wastewater advanced treatment system pumps the medicine to the suction port before the raw water pump and the reuse water pump connected to the reuse water pool , the fungicide added can be mixed evenly with the stirring action of the water pump, which overcomes the problem of reducing the use effect of the fungicide in the pool; and the weakly oxidized environment-friendly fungicide used in the present invention has the characteristics of rapid degradation. There is no residue after use, and it does not affect the use of wastewater after treatment. It also has no drug resistance, that is, when it is added for a long time and the dosage remains unchanged, there is no obvious upward trend in the microbial content of white water. The waste water deep treatment system involved in the present invention has ultra-high treatment efficiency and a design capacity of 3000m3 / d. Its notable feature is that it can be reused according to the requirements of water points, and the comprehensive waste water reuse rate can reach more than 90%.

Description

technical field [0001] The invention relates to the field of papermaking wastewater treatment, in particular to a papermaking wastewater advanced treatment system and process. Background technique [0002] my country's paper industry wastewater discharge and COD discharge rank first in my country's various industrial discharges. The paper industry has the most serious pollution to the water environment. It is not only the primary issue of pollution prevention and control in my country's paper industry, but also the national industrial wastewater treatment standard. and water conservation are the primary issues. How to eliminate the pollution of papermaking wastewater and make use of the precious resources in the waste liquid is a work of great social significance and economic value, which should be attached great importance to. With the development of the economy, our country is increasingly facing the problems of shortage of fresh water resources and shortage of raw materia...

AI Technical Summary

Problems solved by technology

However, at present, about 50% of the total discharge from the papermaking industry has not yet been treated up to the standard, and the recycling of papermaking wastewater after treatment is even rarer. Therefore, the task of pollution prevention and recycling of papermaking wastewater is arduous

[0003] At present, there is a problem of insufficient treatment depth in the treatment of papermaking wastewater. Although the degree of pollution of wastewater is reduced to a certain extent, the treated papermaking wastewater is still dangerous to the environment and cannot be reused. Therefore, the preliminary treated wastewater is further treated. is of great significance

However, the traditional advanced treatment of papermaking wastewater has the following problems: 1. The degree of pre-treatment is not enough, which can easily cause clogging of ultrafiltration membranes and reverse osmosis membranes. The increase in cleaning frequency results in low wastewater treatment efficiency and reduces the use of ultrafiltration membranes and reverse osmosis membranes. life

2. The advanced treatment of traditional papermaking is all through reverse osmosis, resulting in a large amount of reverse osmosis concentrated brine (30%-40%), but due to the high salt content of concentrated brine, there are few usable points, which still causes a large amount of wastewater to be discharged into the environment

3. Traditional papermaking wastewater sterilization devices such as ultraviolet disinfection and adding sodium hypochlorite have low sterilization efficiency, and oxidative bactericides are harmful to papermaking equipment, chemical retention rate, and operator safety

In the papermaking process, adding too much oxidant not only leads to higher processing costs, but also increases the consumption of dyes and other wet-end additives (such as brighteners, sizing agents), increases corrosion, and shortens the life of the felt.

Some oxidants also lead to the formation of AOX

In addition, the excess addition of some oxidants is sufficient to control the microbial load in the liquid, but is ineffective in controlling the biofilm because it is difficult to penetrate into the biofilm matrix

[0005] The Chinese invention patent with the publication number of 103214154A discloses a regeneration and recycling device for advanced papermaking wastewater treatment, which is equipped with a chemical decalcification system, a multimedia filtration system, an electrolysis system, a biological aerated filter (BAF), and an ultrafiltration system. And the reverse osmosis system can effectively treat the wastewater in depth, so that the papermaking wastewater can be recycled. It uses the biological aerated filter to purify the wastewater, which takes up a relatively large space, and is selective for the killing of microorganisms. incomplete

Images