WO2017063304A1

WO2017063304A1 - Papermaking machine white water treatment process

Info

Publication number: WO2017063304A1
Application number: PCT/CN2016/000557
Authority: WO
Inventors: 腾铁生; 张跃平
Original assignee: 新疆国力源投资有限公司
Priority date: 2015-10-13
Filing date: 2016-10-10
Publication date: 2017-04-20
Also published as: CN105369666A

Abstract

Disclosed is a papermaking machine white water treatment process, wherein the collected papermaking machine white water is treated by flocculation and inorganic membrane filtration to obtain clean water; and then the clean water is used to clean coarse cotton cloth. The problem of the reuse of the papermaking machine white water is solved by the process, and a closed cycle of the papermaking machine white water is ensured.

Description

Paper machine white water treatment process

Technical field

The invention relates to a new process for white water treatment of a paper machine.

Background technique

It is well known that the use of water in the papermaking process can not be recycled, can achieve the goal of zero emissions, largely depends on whether the white water of the paper machine can be closed. In the past, paper mills used white water in paper mills. Some paper mills used multiple discs to filter, and a small amount of water was used for washing nets. The wool cloth could not be washed. A large amount of water still had to be returned to the middle water treatment; most paper mills used white water. Direct access to the mid-stage water treatment system is both a waste and an increase in operating costs for water treatment. The main reason why the paper machine white water cannot be recycled is that the simply treated water cannot be used to clean the felt.

Summary of the invention

The technical problem to be solved by the present invention is to overcome the existing drawbacks, and to provide a new process for white water treatment of a paper machine which improves the pulp yield and ensures the closed cycle of the white water of the paper machine.

The object of the present invention is specifically achieved by the following technical solutions:

A paper machine white water treatment process, the collected white water of the paper machine is filtered by flocculation and inorganic membrane to obtain clear water, and then the felt is washed with water.

Specifically, the following steps are included:

1) After collecting, the white water of the paper machine is sent to the flocculation and sedimentation system for flocculation twice, the floc is recovered, and the clean water is recycled to the collection tank.

2) A part of the water in the collection tank is directly used for cleaning the forming network and the equipment sealing water system;

3) Another part of the water in the collection tank is filtered with an inorganic membrane, and the filtered water is stored in a clear water tank for cleaning the high and low pressure water parts of the felt;

4) The collected floes are delivered to the flow delivery system.

Preferably, the flocculating agent in the step 1) is an inorganic flocculating agent.

Further preferably, the flocculating agent is modified diatomaceous earth. Produced by Baishan Liwei Diatomite Integrated Products Co., Ltd., product name: modified diatomaceous earth water purifying agent.

Preferably, 1 kg of flocculating agent per 1 ton of water is purified.

Preferably, the flocculant has a mesh number of 300-350 mesh. The higher the mesh number, the smaller the particles, and the meshing agent has a mesh number of 300-350 mesh, and the flow back system has no effect on the paper surface.

The inorganic film in the step 3) is fired from diatomaceous earth and has a filtration pore size of 5-30 um.

The beneficial effects of the invention:

The process of the invention is used to completely solve the problem of reuse of the white water of the paper machine, and the water collected after the flocculation improves the pulp yield and ensures the closed cycle of the white water of the paper machine. Compared with the prior art, the main advantages are as follows:

1. The process flow is short, and it is not necessary to return to the middle water treatment system to save operating expenses.

2, the floor space is small, the system can be built in the papermaking workshop, saving one-time investment.

3, reached a closed cycle, pointing out the direction for zero discharge of paper.

detailed description

The preferred embodiments of the present invention are described in the following, and the preferred embodiments described herein are intended to illustrate and explain the invention.

Example 1

A white water treatment process for a paper machine includes the following steps:

1) After collecting, the white water of the paper machine is sent to the flocculation and sedimentation system for 2 times flocculation. The flocculant is an inorganic flocculant (modified diatomaceous earth), the dosage is 0.1%, and the mesh number is 300-350 mesh. The floc is recovered and the water is recycled to the collection tank.

2) A part of the water in the collection tank is directly used to clean the forming wire, and the equipment seals water and the like. Since the forming mesh was a 90-mesh polyester mesh, there was no problem in cleaning with 2 times of flocculation.

3) Another part of the water in the collection tank is filtered with an inorganic membrane (modified diatomaceous earth fired), and the filtered water is stored in a clean water tank for cleaning the high and low pressure water of the felt.

4) The collected floc is transported to the flow delivery system, which increases the pulp yield and ensures the closed cycle of the white water of the paper machine.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still The technical solutions described are modified, or some of the technical features are equivalently replaced. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

The utility model relates to a white water treatment process for a paper machine, which is characterized in that: the collected white water of the paper machine is filtered by flocculation and inorganic membrane to obtain clean water, and then the felt is washed with water.
The paper machine white water treatment process according to claim 1, comprising the steps of:

1) After collecting, the white water of the paper machine is sent to the flocculation and sedimentation system for flocculation twice, the floc is recovered, and the clean water is recycled to the collection tank.

2) A part of the water in the collection tank is directly used for cleaning the forming network and the equipment sealing water system;

3) Another part of the water in the collection tank is filtered with an inorganic membrane, and the filtered water is stored in a clear water tank for cleaning the high and low pressure water parts of the felt;

4) The collected floes are delivered to the flow delivery system.
The paper machine white water treatment process according to claim 2, wherein the flocculating agent in the step 1) is an inorganic flocculant.
The white water treatment process for a paper machine according to claim 3, wherein the flocculating agent is modified diatomaceous earth.
The paper machine white water treatment process according to claim 3 or 4, characterized in that the flocculating agent for purifying 1 ton of water is 1 kg.
A white water treatment process for a paper machine according to claim 3 or 4, wherein the flocculant has a mesh number of 300 to 350 mesh.
The paper machine white water treatment process according to claim 2, wherein the inorganic film in the step 3) is fired from diatomaceous earth and has a filtration pore size of 5-30 um.