阅读说明：本技术 一种造纸污泥的处理方法 (Treatment method of papermaking sludge ) 是由 何军 丁纪刚 张元昌 于 2020-11-17 设计创作，主要内容包括：本发明属于污泥处理技术领域,公开了一种造纸污泥的处理方法。所述处理方法包括以下步骤：(1)将煤粉用水进行调质,得到调质剂；(2)将步骤(1)制得的调质剂加入至造纸污泥中,搅拌进行调质；(3)将调质后的造纸污泥采用板框压滤机进行压滤,得到污泥质燃料。所述处理方法简便,成本较低,且能够实现良好的脱水效果,实现造纸污泥的有效资源利用。(The invention belongs to the technical field of sludge treatment, and discloses a treatment method of papermaking sludge. The processing method comprises the following steps: (1) quenching and tempering the coal dust with water to obtain a quenching and tempering agent; (2) adding the conditioner prepared in the step (1) into papermaking sludge, and stirring for conditioning; (3) and (3) performing filter pressing on the tempered paper making sludge by using a plate-and-frame filter press to obtain the sludge fuel. The treatment method is simple and convenient, has lower cost, can realize good dehydration effect, and realizes effective resource utilization of the paper-making sludge.)

1. The method for treating the papermaking sludge is characterized by comprising the following steps of:

(1) quenching and tempering the coal dust with water to obtain a quenching and tempering agent;

(2) adding the conditioner prepared in the step (1) into papermaking sludge, and stirring for conditioning;

(3) and (3) performing filter pressing on the tempered paper making sludge by using a plate-and-frame filter press to obtain the sludge fuel.

2. The process according to claim 1, wherein the conditioner in the step (1) has a dryness of 45 to 55%.

3. The treatment method according to claim 1, wherein the mass ratio of the paper sludge to the conditioner in the step (2) is 1: (0.6-0.8).

4. The process according to claim 1, wherein the stirring time in step (2) is 1.5 to 3 hours.

5. The process of claim 1, wherein the stirring in step (2) is performed by center-driven stirring or submerged plug-flow stirring.

6. The process according to claim 5, wherein the rotation speed of the step (2) is 8-10r/min when the central transmission type stirring is adopted; the rotating speed of the submersible plug flow stirring is 720 r/min.

7. The process according to claim 1, wherein the pressure filtration in the step (3) is carried out for a period of 1 to 3 hours at a pressure of 0.8 to 1.8 MPa.

Technical Field

The invention belongs to the technical field of sludge treatment, and particularly relates to a treatment method of papermaking sludge.

Background

The sludge is solid sediment substances generated in the process of water and sewage treatment, pollutants and nutrient components in the sewage are aggregated under the action of mass-propagated bacteria and chemical agents, and the gradually-increased granular structure is finally precipitated in the water to form the sludge. In general, by adding polymeric flocculant and adopting physical concentration method, part of free water in sludge can be removed to form dewatered sludge as seen by us. However, after the above-mentioned preliminary dehydration treatment, the water content thereof is still as high as 80 to 85%, which is called excess sludge, and it is extremely difficult to continue the dehydration of the excess sludge.

Since the microorganisms in the excess sludge are an important component thereof, the organic matter content of the excess sludge is rather high, up to 50-60% on a dry matter basis. Bacteria and most of parasitic organisms are left in the sludge, and viruses are adsorbed on particles in the sewage and are deposited in the sludge along with the precipitation of the particles. The pathogenic bacteria in each gram of domestic sludge and industrial sludge are hundreds of millions, and after sludge which is not properly treated enters the environment, pathogenic microorganisms and parasitic ova carried in the sludge, heavy metals which are difficult to treat and persistent organic matters directly bring secondary pollution to water and atmosphere. Obviously, if the sludge is not properly disposed of, not only is the effective treatment capacity of the sewage treatment system reduced, but it also poses a serious threat to the ecological environment and human activities.

Generally, when the papermaking sludge is mechanically treated, the treatment effect of the final papermaking sludge is directly related to the selection of sludge dewatering equipment. For example, a belt filter press can usually dehydrate paper sludge to a water content of 80% or more, a plate filter press can dehydrate sludge to a water content of 75% or more, a diaphragm filter press can dehydrate paper sludge to a water content of about 70%, and a high-pressure sludge press can dehydrate paper sludge to a water content of 50% or less at a time. However, the above equipment with better sludge dewatering effect has higher manufacturing cost and use cost, and enterprises generally have difficulty in bearing the high sludge treatment cost.

The papermaking sludge produced in the papermaking industry contains a large amount of organic matters, so that the papermaking sludge has high energy utilization value, and can be converted into sludge fuel by dewatering the papermaking sludge to a higher degree, thereby realizing the utilization of resources.

Therefore, it is desirable to provide a method for treating paper sludge, which is simple, low in cost and excellent in dewatering effect.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art described above. Therefore, the invention provides a papermaking sludge treatment method which is simple and convenient, has lower cost, can realize good dehydration effect and realizes effective resource utilization of papermaking sludge.

A method for treating papermaking sludge comprises the following steps:

(1) quenching and tempering the coal dust with water to obtain a quenching and tempering agent;

(2) adding the conditioner prepared in the step (1) into papermaking sludge, and stirring for conditioning;

(3) and (3) performing filter pressing on the tempered paper making sludge by using a plate-and-frame filter press to obtain the sludge fuel.

In the prior sludge treatment method, a medicament or a polymeric flocculant which can cause microorganisms to break walls is added into sludge to be treated, and the water content of the sludge is further reduced by pressure filtration. However, the heat value of the treated sludge is not high, and if the sludge is subjected to boiler incineration, additional coal is required to be added for mixing, so that a good combustion effect can be achieved.

However, the present invention has found that it is a great advantage if coal is added before sludge treatment as compared to adding additional coal directly at the time of boiler incineration. The odor of the sludge is reduced by adding the pulverized coal to adsorb odor substances of the sludge before the sludge treatment; and the addition of the coal dust can also be beneficial to the wall breaking of the cell walls of the sludge, namely the breaking of the cell walls of microorganisms is promoted through the physical grinding of the coal dust in the sludge, so that the water in the cells overflows, and the water in the sludge is reduced to a greater extent.

The invention can avoid the caking phenomenon when the coal powder is directly added into the paper making sludge by firstly mixing the coal powder and the water and then adding the mixture into the paper making sludge.

By adopting the method for treating the papermaking sludge, the water content of the finally prepared sludge fuel is lower than 50 percent, and the heat value can be improved to 2000Kcal/m³Thus, the combustion effect is good.

Preferably, the dryness of the modifying agent in the step (1) is 45-55%.

Preferably, the mass ratio of the papermaking sludge to the modifying agent in the step (2) is 1: (0.6-0.8). When the amount of the conditioner is less than the mass ratio, the dewatering effect of the paper sludge is insufficient, the heat value of the prepared sludge fuel is low, and coal needs to be additionally added to meet the requirement of boiler incineration. When the amount of the modifying agent is higher than the mass ratio, the heat value of the sludge fuel is not obviously increased, and the cost is unnecessarily increased.

Preferably, the stirring time in the step (2) is 1.5-3 h.

Preferably, the stirring mode in the step (2) is central transmission type stirring or diving plug flow stirring.

More preferably, the rotation speed is 8-10r/min when the central transmission type stirring is adopted in the step (2); the rotating speed of the submersible plug flow stirring is 700-750 r/min.

Preferably, the pressure filtration time in the step (3) is 1-3 hours, and the pressure of the pressure filtration is 0.8-1.8 MPa.

Compared with the prior art, the invention has the following beneficial effects:

the invention adds the coal powder before the filter pressing of the paper making sludge, can adsorb odor substances of the sludge, reduces the odor of the sludge, and is beneficial to breaking the cell wall of microorganisms of the paper making sludge. And can reach good dehydration effect under the condition of not additionally adding a wall-breaking medicament or a flocculating agent, has the advantages of simplicity and convenience and lower cost, thereby realizing the effective resource utilization of the paper sludge. Meanwhile, the treatment method does not add any toxic and harmful substance, and does not generate any toxic and harmful substance and gas, so that the whole process of preparing the sludge fuel can completely realize clean production.

Detailed Description

In order to make the technical solutions of the present invention more apparent to those skilled in the art, the following examples are given for illustration. It should be noted that the following examples are not intended to limit the scope of the claimed invention.

The starting materials, reagents or apparatuses used in the following examples are conventionally commercially available or can be obtained by conventionally known methods, unless otherwise specified.

Example 1

The embodiment provides a treatment method of papermaking sludge, which comprises the following steps:

(1) quenching and tempering the coal dust with water to obtain a quenching and tempering agent, wherein the dryness of the quenching and tempering agent is 48%;

(2) adding the modifying agent obtained in the step (1) into papermaking sludge, wherein the mass ratio of the papermaking sludge to the modifying agent is 1: 0.6, stirring for 2 hours at a rotating speed of 10r/min by adopting central transmission type stirring to finish tempering;

(3) and (3) performing filter pressing on the tempered paper sludge by using a plate-and-frame filter press, wherein the filter pressing time is 2 hours, and the filter pressing pressure is 1.6Mpa, so as to obtain the sludge fuel.

The water content of the sludge fuel prepared by the embodiment is 50 percent, and the calorific value is improved to 2000Kcal/m³And has good combustion effect.

Example 2

The embodiment provides a treatment method of papermaking sludge, which comprises the following steps:

(1) quenching and tempering the coal dust with water to obtain a quenching and tempering agent, wherein the dryness of the quenching and tempering agent is 51%;

(2) adding the modifying agent obtained in the step (1) into papermaking sludge, wherein the mass ratio of the papermaking sludge to the modifying agent is 1: 0.8, stirring for 1.5 hours at the rotating speed of 720r/min by adopting submersible plug flow stirring to finish tempering;

(3) and (3) performing filter pressing on the tempered paper sludge by using a plate-and-frame filter press, wherein the filter pressing time is 1.5 hours, and the filter pressing pressure is 1.8Mpa, so as to obtain the sludge fuel.

The water content of the sludge fuel prepared by the embodiment is 45 percent, and the calorific value is improved to 2300Kcal/m³And has good combustion effect.

Comparative example 1

The comparative example provides a method for treating papermaking sludge, comprising the following steps:

and (3) directly carrying out filter pressing on the papermaking sludge by using a plate-and-frame filter press, wherein the filter pressing time is 2 hours, and the filter pressing pressure is 1.8Mpa, so as to obtain the sludge fuel.

The water content of the sludge fuel prepared by the comparative example is 75%, and the sludge fuel can not be basically used for combustion under the condition of not additionally adding fuel.

Comparative example 2

The comparative example provides a method for treating papermaking sludge, comprising the following steps:

(1) mixing a polymeric flocculant, ferric salt and calcium salt according to a mass ratio of 1:1:1 to prepare a conditioning agent;

(2) adding the conditioner prepared in the step (1) into papermaking sludge, wherein the mass ratio of the papermaking sludge to the conditioner is 1: 0.8, stirring for 1.5 hours at the rotating speed of 720r/min by adopting submersible plug flow stirring to finish tempering;

(3) and (3) performing filter pressing on the tempered paper sludge by using a plate-and-frame filter press, wherein the filter pressing time is 1.5 hours, and the filter pressing pressure is 1.8Mpa, so as to obtain the sludge fuel.

The sludge fuel prepared by the comparative example has the water content of 62 percent and the heat value of 1000Kcal/m³. Therefore, the sludge fuel prepared by the comparative example has high water content and low heat value, and can be well combusted only by additionally adding fuel when being burnt by a boiler.

Comparative example 3

The comparative example provides a method for treating papermaking sludge, comprising the following steps:

(1) mixing lime and water, adding the mixture into the papermaking sludge, and stirring for 1.5 hours at the rotating speed of 720r/min by adopting submersible plug flow stirring to finish tempering;

(2) and (3) performing filter pressing on the tempered paper sludge by using a plate-and-frame filter press, wherein the filter pressing time is 1.5 hours, and the filter pressing pressure is 1.8Mpa, so as to obtain the sludge fuel.

The water content of the sludge fuel prepared by the comparative example is 55%, and the heat value is 1150 kilocalories. The water content of the sludge fuel can be reduced to a certain degree by adding lime for wall breaking, but the calorific value cannot be improved, so that extra fuel is still required to be added for combustion in the subsequent boiler incineration. Meanwhile, the addition of lime corrodes equipment and is not beneficial to the long-term operation of a sludge treatment system.