CN105948425B - Papermaking wastewater treatment system - Google Patents

Abstract

A papermaking wastewater treatment system, including a waste water tank, a first flocculation sedimentation tank, a fiber recycler, a second flocculation sedimentation tank, a biodegradation tank and a reuse water tank, the waste water tank is connected to the inlet water of the first flocculation sedimentation tank end, the water discharge end of the first flocculation settling tank is connected to the water inlet end of the fiber recovery device through a pipeline, and the water discharge end of the fiber recovery device is connected to the water inlet end of the second flocculation settlement tank, and the second The water discharge end of the flocculation settling tank is connected to the water inlet end of the biodegradation tank, and the water discharge end of the biodegradation tank is connected to the reuse water tank. The bottom of the first flocculation settling tank is provided with a sludge tank, and the second flocculation settling tank It includes an upper layer, a middle layer and a bottom layer, and the upper layer, the middle layer and the bottom layer are respectively provided with drainage pipes connected to biological sedimentation tanks, return pipes connected to the first flocculation sedimentation tank and sewage discharge pipes connected to sludge tanks. The waste water treatment effect of the invention is thorough, the energy consumption is low, and it is favorable for popularization and application.

Description

Papermaking wastewater treatment system

technical field

The invention relates to a low-consumption papermaking wastewater treatment system, which belongs to the field of industrial wastewater treatment.

Background technique

Water is the source of life. The worldwide water scarcity problem is becoming more and more serious. Water conservation has always been advocated. As a large water consumer, industrial production industries should do a good job in reducing industrial water discharge, improving water recycling rate, and avoiding industrial waste. Waste of water.

At the same time, the problem of environmental pollution is becoming more and more serious. Improving environmental awareness and reducing pollutants, especially the discharge of sewage or wastewater from industrial production, is one of the important causes of environmental pollution. How to deal with the discharge of industrial sewage or wastewater has become a key factor in reducing environmental pollution an important measure.

The papermaking industry is an industry that pollutes water sources seriously. The papermaking process requires a large amount of water. Traditional paper mills discharge a large amount of polluted water sources, polluting water quality and soil, and producing a lot of unpleasant odors. The wastewater discharged from the paper mill contains the papermaking fibers remaining in the wastewater during the papermaking process, resulting in the loss and waste of papermaking fibers; the wastewater from the paper mill also contains papermaking additives, most of which are non-volatile and will remain in the soil Or sewage, discharge in the environment will cause pollution that cannot be eliminated for a long time.

The entire production process of the pulp and paper industry requires a large amount of water, which collects a large amount of industrial harmful substances during the production process, which cannot be directly used, and will pollute the environment if it is directly discharged. The recycling and reuse of wastewater has significant economic and social value and determines the survival and development of papermaking enterprises.

In the paper industry, chemical precipitation, air flotation treatment and biological oxidation are usually used to treat sewage or wastewater.

At present, the traditional process of primary environmental protection treatment of papermaking is primary precipitation or physical and chemical flocculation precipitation. The flocculation process has high removal efficiency, especially it can remove a large number of postal pollutants that are difficult to degrade, which lays the foundation for the next step of biochemical treatment. However, such The treatment is only suitable for wastewater with a low load. European countries are the most advanced in terms of physical and chemical treatment, and have basically eliminated advection sedimentation tanks and adopted advanced sedimentation technologies such as milk flushing clarifiers and suspension clarifiers.

In recent years, biofilm ultrafiltration technology, reverse osmosis, electrodialysis, and ion exchange treatment methods have emerged continuously. In the papermaking industry, on the one hand, due to the high cost of treatment, and on the other hand, due to the complex composition of papermaking wastewater, the treatment is difficult. Therefore, there is no mature industrialized treatment technology available so far.

After searching, the inventor found that the patent number is 2009100012718, and the patent name is the invention patent of papermaking wastewater treatment method, which discloses the papermaking wastewater treatment method through filtration, UPCB treatment, biochemical treatment, and advanced treatment. The invention is based on the UPCB treatment process , to achieve the purpose is to lower the cost of waste water, the waste water treatment efficiency is high, and can achieve satisfactory results. The present invention does not take into account the air flotation method, a treatment process with good wastewater treatment effect and low cost. The required control parameters of the UPCB treatment process are very complicated, and there are great difficulties in industrial applications that are difficult to implement.

The inventor also retrieved an invention patent with the patent number 2009100012703 and the patent name is the treatment method of papermaking wastewater. This patent discloses the use of filtration, flocculation sedimentation, QA2O treatment, and advanced treatment. The invention of this patent lies in the use of QA2O treatment The treatment process replaces the conventional biochemical treatment method to achieve the beneficial effects of cost saving, good treatment effect and simple process. However, such a process requires the use of a large amount of chemicals, which remain in the treated wastewater, which brings many restrictions on the reuse of wastewater.

And both patents do not consider the fiber recovery problem in the waste water, wasting the fiber in the waste water.

Contents of the invention

In order to solve the above existing problems, the present invention discloses a low-consumption papermaking wastewater treatment system. This wastewater treatment system makes full use of the wastewater treatment process of flocculation and sedimentation. It is a relatively low-consumption wastewater treatment method that can achieve ideal papermaking The effect of wastewater treatment.

A low-consumption papermaking wastewater treatment system is characterized in that it includes a waste water tank, a first flocculation sedimentation tank, a fiber recycler, a second flocculation sedimentation tank, a biodegradation tank and a reuse water tank, and the waste water tank is connected to The waste water discharge pipeline of the workshop, the waste water in the waste water tank is transported to the water inlet end of the first flocculation settling tank through the waste water pipeline, and the water discharge end of the first flocculation settling tank is connected to the inlet of the fiber recovery device through a pipeline. Water end, the water discharge end of the fiber recycler is connected to the water inlet end of the second flocculation sedimentation tank, the water discharge end of the second flocculation sedimentation tank is connected to the water inlet end of the biodegradation tank, the biodegradation tank The water discharge end is connected to the reuse water tank.

A sludge tank is arranged at the bottom of the first flocculation-settling tank.

The second flocculation-settling tank includes three layers, namely the upper layer, the middle layer and the bottom layer. The upper layer, the middle layer and the bottom layer are respectively provided with drain pipes connected to the biological sedimentation tank and return pipes connected to the first flocculation-settling tank. and the sewage pipe connected to the sludge tank.

Filter layers are respectively arranged between the upper layer and the middle layer and between the middle layer and the bottom layer of the second flocculation sedimentation tank.

There are more than two first flocculation-settling tanks, and more than two first flocculation-settling tanks are connected in series, and the water discharge end of the first flocculation-settling tank is connected to the inlet of the adjacent first flocculation-settling tank. At the water end, all the first flocculation and settling tanks share a sludge tank.

The second flocculation-settling tank has more than two, and more than two second flocculation-settling tanks are connected in series, and the water discharge end of the second flocculation-settling tank is connected to the inlet of the adjacent second flocculation-settling tank. At the water end, the upper, middle and bottom layers of all the second flocculation-settling tanks are respectively provided with drainage pipes connected to the biodegradation tank, return pipes connected to the first flocculation-settling tank and sewage pipes connected to the sludge tank, All the second flocculation settling tanks share one sludge tank.

All the first flocculation-settling tanks and all the second flocculation-settling tanks share one sludge tank.

The working principle of the present invention is:

1. The papermaking wastewater discharged from the paper mill is first discharged to the wastewater pool, which accepts and stores the wastewater for extraction in the subsequent treatment process;

2. The papermaking wastewater extracted from the wastewater tank directly comes from the wastewater tank. The papermaking wastewater contains a large amount of SS, COD, BOD and other polluting and harmful substances. This wastewater enters the first flocculation and sedimentation tank. Flocculants and coagulants enhance the flocculation and settlement of pollutants and harmful substances in wastewater, and the settled harmful substances are discharged to the sludge tank for further treatment, and the upper layer of wastewater that is settled and treated enters the fiber recycler;

3. The SS of the waste water sheet treated by a flocculation and sedimentation is greatly reduced, the damage of the waste water to the fiber recycler will be greatly reduced, and the purity and cleanliness of the recovered papermaking fibers are much higher, which is conducive to the friendly and long-term use of the equipment;

4. The SS and papermaking fibers in the wastewater treated by the fiber recycler are greatly reduced, and the COD, BOD and other pollution in the wastewater are also removed to a certain extent. After the second flocculation and sedimentation, the COD and BOD in the wastewater are further removed. Wait for pollution, improve the clarity of wastewater, and reduce the content of harmful substances in wastewater;

5. Biodegradation can remove the unpleasant smell of wastewater, improve the clarity of wastewater, and remove pollutants that have not been flocculated and settled, so that wastewater can finally reach the standard of reuse water in papermaking workshops.

Beneficial effects of the present invention:

(1) It mainly removes SS, COD, BOD and other pollution and harmful substances in wastewater through flocculation and sedimentation, with low energy consumption, relatively mild treatment process, and low requirements for equipment;

(2) After the waste water undergoes the first flocculation and sedimentation, most of the SS is removed, and then the fiber is recycled. The waste water does little damage to the fiber recycling equipment, and the recycled fiber is relatively clean and high in purity, which is beneficial to reduce the papermaking cost of recycling. The amount of pollutants brought in when the fiber is reused in the pulping process;

(3) The upper layer of wastewater obtained from the second flocculation and sedimentation treatment is relatively clean treated wastewater, which can be directly transported to the biological sedimentation tank, and then reaches the reuse water standard through biological sedimentation. The middle layer of wastewater obtained from the second flocculation and sedimentation treatment is The water layer where COD, BOD and other polluted and harmful substances are relatively concentrated is transported to the first flocculation sedimentation tank, where it is flocculated again to improve the effect of wastewater treatment;

(4) The settled sludge from the first flocculation-settling treatment and the second flocculation-settling treatment enters the sludge tank, and the harmful substances in the sludge are further treated in the sludge tank, so that the settled substances reach the environment Emission Standards.

Description of drawings

Fig. 1 is a schematic diagram of the device connection relationship of the present invention.

Detailed ways

The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention but not to limit the scope of the present invention.

The accompanying drawing is only a specific embodiment of the present invention.

Example 1:

Fig. 1 is a schematic diagram of the connection relationship of the equipment of the present invention. It can be seen in conjunction with the accompanying drawings that the present invention includes a waste water tank, a first flocculation settlement tank, a fiber recovery device, a second flocculation settlement tank, a biodegradation tank, a sludge tank and a recycling tank. A water pool, the waste water pool is connected to the waste water discharge pipeline from the papermaking workshop, the waste water in the waste water pool is transported to the water inlet end of the first flocculation settling tank through the waste water pipeline, and the water discharge end of the first flocculation settling tank Connect to the water inlet end of the fiber recovery device through a pipeline, the water discharge end of the fiber recovery device is connected to the water inlet end of the second flocculation settlement tank, and the water discharge end of the second flocculation settlement tank is connected to the biodegradation tank The water inlet end of the biodegradation pool is connected to the reuse water pool.

A sludge tank is arranged at the bottom of the first flocculation-settling tank. The sludge tank is used to treat the pollutants settled in the first flocculation and sedimentation tank.

The second flocculation-settling tank includes three layers, namely the upper layer, the middle layer and the bottom layer. The upper layer, the middle layer and the bottom layer are respectively provided with drain pipes connected to the biological sedimentation tank and return pipes connected to the first flocculation-settling tank. and the sewage pipe connected to the sludge tank. The second flocculation sedimentation tank is divided into three stages for treatment to improve the treatment effect.

Filter layers are respectively arranged between the upper layer and the middle layer and between the middle layer and the bottom layer of the second flocculation sedimentation tank.

Example 2:

There are more than two first flocculation-settling tanks, and more than two first flocculation-settling tanks are connected in series, and the water discharge end of the first flocculation-settling tank is connected to the inlet of the adjacent first flocculation-settling tank. At the water end, all the first flocculation and settling tanks share a sludge tank.

The connection relationship between the waste water tank, the fiber recoverer, the second flocculation and sedimentation tank, the biodegradation tank, the sludge tank and the reused water tank is consistent with that of Embodiment 1.

Example 3:

The second flocculation-settling tank has more than two, and more than two second flocculation-settling tanks are connected in series, and the water discharge end of the second flocculation-settling tank is connected to the inlet of the adjacent second flocculation-settling tank. At the water end, the upper, middle and bottom layers of all the second flocculation-settling tanks are respectively provided with drainage pipes connected to the biodegradation tank, return pipes connected to the first flocculation-settling tank and sewage pipes connected to the sludge tank, All the second flocculation settling tanks share one sludge tank.

The connection relationship of the waste water tank, the fiber recoverer, the first flocculation and sedimentation tank, the biodegradation tank, the sludge tank and the reused water tank is consistent with that of Embodiment 1.

Example 4:

The first flocculation-settling tank and the second flocculation-settling tank have more than two, and the connection relationship between more than two first flocculation-settling tanks and the second flocculation-settling tank is consistent with Embodiment 2 and Embodiment 3 .

Example 5:

The first flocculation-settling tank and the second flocculation-settling tank have more than two, and the connection relationship between more than two first flocculation-settling tanks and the second flocculation-settling tank is consistent with Embodiment 2 and Embodiment 3 , and all the first flocculation-settling tanks and all the second flocculation-settling tanks share one sludge tank.

The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above technical means, but also include technical solutions composed of any combination of the above technical features.

Inspired by the above-mentioned ideal embodiment according to the present invention, through the above-mentioned description content, relevant workers can make various changes and modifications within the scope of not departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, but must be determined according to the scope of the claims.

Claims (1)

1. a kind of method of work of the papermaking wastewater treatment system of low consumption, it is characterized in that, papermaking wastewater treatment system includes waste water Pond, first of Flocculating setting basin, fiber recoverer, second Flocculating setting basin, biodegradable pond and reuse pool, the waste water Pond connects the discharge of wastewater pipeline from paper machine room, and the waste water in the wastewater disposal basin is transported to first of wadding by waste pipe The water inlet end of solidifying settling tank, the water outlet side of first of Flocculating setting basin are connected to the water inlet of fiber recoverer by pipeline End, the water outlet side of the fiber recoverer are connected to second Flocculating setting basin water inlet end, the second Flocculating setting basin Water outlet side be connected to the water inlet end in biodegradable pond, the water outlet side in biodegradable pond is connected to reuse pool；

The bottom of first of Flocculating setting basin is provided with sludge-tank；

The second Flocculating setting basin includes three layers, respectively upper strata, middle level and bottom, the upper strata, middle level and bottom It is respectively arranged with and is connected to the drainpipe in biodegradable pond, is connected to the return duct of first Flocculating setting basin and is connected to sludge The blow-off pipe in pond, filtering is respectively arranged between the upper strata and middle level of the second Flocculating setting basin between middle level and bottom Layer；

First of Flocculating setting basin has two or more, and more than two first of Flocculating setting basin is connected in series, and first The water outlet side of road Flocculating setting basin is connected to the water inlet end of first adjacent of Flocculating setting basin, all first of flocculating settings Pond shares a sludge-tank；

The second Flocculating setting basin has two or more, and more than two second Flocculating setting basins are connected in series, and second The water outlet side of road Flocculating setting basin is connected to the water inlet end of adjacent second Flocculating setting basin, and the flocculation of all seconds is heavy Upper strata, middle level and the bottom in drop pond, which are respectively arranged with, to be connected to the drainpipe in biodegradable pond, is connected to first of flocculating setting The return duct in pond and the blow-off pipe for being connected to sludge-tank, all second Flocculating setting basins share a sludge-tank；

The method of work, including：The paper waste come is extracted from wastewater disposal basin, into first of Flocculating setting basin, is passed through Increase flocculant and flocculation aid in waste water, strengthen flocculation, the sedimentation of the pollutant, harmful substance in waste water, settle down Discharge of poisonous waste is further handled to sludge-tank；The upper strata waste water of settlement treatment, into fiber recoverer.