KR100408627B1 - Pollution control material for paper - Google Patents

Abstract

The present invention relates to an antifouling composition for paper making, comprising an organic acid having a carboxyl group (-COOH), a phosphonate (-PO ₃ H ₂ ) compound, and an anionic surfactant as a main component to remove the contaminant generated in the papermaking process, Provided is an antifouling composition for paper making. The antifouling composition of the present invention is prepared in an aqueous solution type and can suppress scale generation even with a small amount of input.

Description

Pollution control material for papers {Pollution control material for paper}

The present invention relates to an antifouling composition for papermaking, and more particularly, to remove contaminants of dehydrated felt by calcium carbonate, which is frequently used as a filler of inorganic materials, especially neutral paper, among various contaminants generated during the papermaking process. The present invention relates to a papermaking anti-fouling agent for suppressing scale generation due to an increase in white water circulation rate.

The contaminants generated in the papermaking process are commonly referred to as pitches or deposits, and the contaminants are introduced during the papermaking process mainly by main / subsidiary materials, various additives, and process water (white water). In particular, excess raw materials and additives remaining after forming paper are circulated and deposited in storage tanks, piping equipment, etc., causing problems.

The initial contaminant form is generally anionic in the form of colloidal particles ranging from 0.2 µm to 2 µm, but grows to the size of 100 µm before and after the agglomeration of particles while undergoing changes in temperature, pH and physical force in the process. Afterwards, dehydration rate and excessive heat loss are caused, which are the cause of quality problems such as cracks, spots, pinholes, and the like, and deterioration of process efficiency.

The recent rapid increase in contaminants in the papermaking process has been aggravated by larger paper machines (more than 500 T / day) and high speeds (more than 1500 m / min), and the recycling rate of process effluent is also increasing due to legal regulations. The situation is more difficult than in the past.

The main chemical properties of contaminants are generally divided into organic, inorganic and slime contaminants, but most of the contaminants found in the field are composed of a mixture of contaminants rather than a single component. . Therefore, when classifying the contaminants, it is appropriate to divide them into inorganic, organic, and microbial types according to the contaminants that constitute the main components.

Table 1 Sources and Main Components of Organic Pitch

Kinds Inflow source main ingredient Funnel content Tree pitch Tree (extract) Fatty acids, resin acids, phenols, terpenes, uncompounds (sterols, etc.) Pulp Cooking and Mechanical Cutting 10% Tree (lignin) Three-dimensional combination of phenylpropane 25-30% Sticky Ink Beeswax, resin (polystyrene butadiene polymer) Dissociation and Deinking Process 34-104 (l b / t) Notice (adhesive) EVA, starch, beeswax etc Sediment by additive Antifoam Fatty acids, fatty alcohols, emulsions of esters, mineral oils Inflow into process with process additive 0.3-3% / ton of paper use Withhold PEI, PEO, etc. Dry Strength Enhancer Polyacrylamide, Polyvinyl Alcohol Wet Strength Enhancer Melamine-Formaldehyde Resin, Epoxy, Urea Size Rosin, natural beeswax, glue, synthetic resin, etc. Starch Carboxylate or amino reactants of cereals, corn and wheat starch Latex Styrene Butadiene, Vinyl Acetate, Acrylic Ester Flocculant Acrylamide

[Table 2] Sources and Major Components of Inorganic Pitch

Admission main ingredient Flow path Remarks Coating pigment Kaolin, Ceramic Mud, TiO ₂ , ZnS Coating process additives 2-40% Sheet filter CaCO ₃ , Talc, etc. Process additives Alum Al ₂ (SO ₄ ) ₃ Add when sizing Process water Ca, Mg, etc. Hardness of process water 200-1500 ppm (Ca concentration) Facility scale Ca (OH) ₂ , CaSO _4, Ca ₃ (PO ₄ ) ₂ , AlPO ₄ Process scale dissolution Mineral of wood CaCO ₃ usually contains 55 ppm or more Cooking of pulp

[Table 3] Sources of slime and main components

Inflow source main ingredient Funnel Remarks bacteria It is the main cause of slime and is diverse in anaerobic and aerobic Ingress into the process through raw materials, air, water, etc. Found in high temperature M / C Birds It grows in the absence of light and grows slowly. Plugging of Screens spawn Prefer aerobic conditions Pulp, found among unemployed leaven Mostly Sporeless Yeast Homogeneous Found in Great White Paper M / C mold Rarely found but also degrades resin Causes of Raw Material Damage

In addition, various contaminants are mixed in the process, but in most cases, inorganic metal ions (Ca, Mg, Si, Al, etc.) act as nuclei of the contaminants. very important. There are three main methods for controlling different types of contaminants. First of all, mechanical control is mainly used in the raw material, and it removes contaminants by using various screens and washing machines, and also removes contaminants by centrifugation of solutions or various filters. do. Secondly, the chemical control removes more than 90% of the contaminants in the process by the mechanical control, and then performs chemical control on the remaining contaminants. Specific methods include dispersion by surfactants, adsorption of contaminants by talc, passivation to prevent adhesion of contaminants on specific surfaces, fiber fixing of contaminants, and various Solvents can be used to boil out additives. Table 4 below is a table comparing the chemical control operation and characteristics of the contaminants.

[Table 4] Chemical Control and Characteristics of Pitch

Mechanism Advantages Disadvantages Type of control Dispersion Using electrical repulsive force between particles Eliminates temporary plugging and excellent dispersing power Foaming and low retention. Nonionic or Anionic Surfactants Pollutant adsorption Adsorption of hydrophobic surfaces to suppress aggregation of particles Less burden on the machine and economical. Weak in mechanical cutting Talc, Asbestos Passivation Formation of water-soluble coatings on specific areas Effective for specific areas. Not applicable to the entire machine Low molecular weight cationic material Cationic polymer Pitch particles stuck to the fiber and discharged out of the system Excellent retention of fibers and suitable for closed systems Relatively expensive and difficult to apply in the field. Cationic polymer Boy out Dissolution by solvent or detergent Economical and easy to apply The environmental pollution is severe. Not applicable to continuous process Xylene, kerosene, sodium hydroxide, etc.

Finally, biologic and biochemical controls are enzymatic for enzymatic degradation.

control, suppression of slime formation by various slime removers

There is a phrase.

The most widely used chemical treatment method is a high concentration washing method using a solvent (xylene, kerosene) or sodium hydroxide. The high concentration cleaning method is excellent in terms of economic effect, but it cannot be carried out during the operation of the machine, and the environmental pollution problem is raised due to the increase of chemical oxygen demand (COD) due to the high concentration cleaning and the frequent use of solvents.

Accordingly, Korean Patent Publication No. 96-1697 discloses phosphonic acid, ethylene oxide to alkylphenols, and anionic pitch dispersant as a paper-based antifouling composition that can suppress the adsorption of contaminants and growth of adsorbates in the papermaking process. Patent Publication No. 95-30561 discloses a cleaning agent for removing contaminants attached to the felt during the papermaking process.

An object of the present invention is to provide an antifouling agent that can suppress contamination occurring in a papermaking process.

In order to achieve the above object, the present invention provides a paper-based antifouling composition comprising an organic acid having a carboxyl group (-COOH), a phosphonate (-PO ₃ H ₂ ) compound, and an anionic surfactant. .

Hereinafter, the present invention will be described in detail.

The present invention suppresses or eliminates the formation of contaminants by controlling the inorganic metal ions that act as the main cause of the contaminants occurring in the papermaking process.

The papermaking pollution inhibitor of the present invention includes an organic acid having a carboxy group (-COOH), a phosphonate (-PO ₃ H ₂ ) compound, and a sulfate of a higher alcohol up to C ₁₂ to C ₁₈ which is an anionic surfactant.

The organic acid is preferably glycolic acid (Glycolic acid), tartaric acid (Tartaric acid), lactic acid (Lactic acid), levulic acid (Levulic acid), succinic acid (Succinic acid), and acetic acid (Acetic acid), and succinic acid is Most preferred. The organic acid is excellent in removing pollutants and is effective in removing metal oxides due to corrosion, and reacts with ions such as Ca ²⁺ and Mg ²⁺ in a solution to form a complex to inhibit scale generation. The organic acid is preferably contained in 5% to 60% by weight, most preferably 20% to 40% by weight in the papermaking antifouling agent of the present invention. If the content of the organic acid-containing antifouling composition for papermaking is less than 5% by weight, the antifouling effect may be insignificant, and if it exceeds 60% by weight, the organic acid in the composition may be precipitated, so that the phase stability of the composition may be poor.

The phosphonate compound, which is the organic phosphate, is used as a representative chelating agent.⁺⁺, Fe⁺⁺By forming a water-soluble complex with ions such as to prevent the generation of scale, unlike other chelating agents, it has a function of inhibiting the crystal growth of contaminants, it is excellent in the use of small amounts. In addition, it has excellent heat and pH stability and shows excellent chelating effect even when pulp is cooked or bleached in highland. The phosphonate compound, which is a main component of the papermaking antifouling agent of the present invention, preferably includes HEDP (1-hydroxy ethylene-1,1-diphosphonic acid), ATMP (aminotrimethyl phosphonic acid), and a salt (Na) compound of the compound. Most preferred is 1-hydroxy ethylene-1,1-diphosphonic acid (HEDP). The phosphonate compound is preferably included in the papermaking antifouling agent of the present invention in 5% by weight to 30% by weight, most preferably 10% by weight to 20% by weight. If the content of the phosphonate compound in the paper antifouling composition is less than 5% by weight, the chelating effect may be reduced by half, and the antifouling effect may be insignificant. When the phosphorus concentration contained in the composition is higher than the environmental standard value, there may be a need to proceed with a separate phosphorus removal process.

In addition, the anionic surfactant contained in the papermaking antifouling agent of the present invention is a sulfate of a higher alcohol of C ₁₂ to C ₁₈ . The anionic surfactant has excellent detergency and pitch dispersing ability to penetrate contaminants and disperse the particles, and stably disperses them by forming a micellar structure to suppress aggregation of contaminants in the system and consequent particle formation. Clean the material contact surfaces of the facility, etc., to prevent scale deposits. The anionic surfactant in the papermaking antifouling agent of the present invention is C ₁₂ to C ₁₈ higher alcohol sulfate Sodium laury sulfate, Sodium Myristyl sulfate, Sodium cetyl sulfate And calcium stearyl sulfate, and sodium lauryl sulfate is most preferred. The anionic surfactant is preferably included in the papermaking antifouling agent of the present invention in 0.01% by weight to 5% by weight, most preferably 0.1% by weight to 2% by weight. If the amount of the anionic surfactant contained in the antifouling composition for papermaking is less than 0.01% by weight, the antifouling effect may be inferior due to the low penetrating power of the antifouling composition. Alternatively, a large amount of bubbles may be formed during use, so that it may be difficult to proceed the process smoothly.

In addition to the main components described above, the papermaking antifouling agent of the present invention is 0.1 to 2% by weight of polyacrylamide or 0.1 to 3% by weight of polyoxyethylene octyl phenyl ether. More).

The papermaking antifouling agent of the present invention is preferably prepared in a water-soluble formulation in a conventional manner.

Hereinafter, preferred examples are provided to aid in understanding the present invention. However, the following examples are provided only to more easily understand the present invention, and the present invention is not limited to the following examples.

Example 1

300 g Succinic acid, 100 g HEDP (1-hydroxy ethylene-1, 1-diphosphonic acid), 30 g sodium lauryl sulfate 50 g Polyacrylamide After mixing with 630 g of deionized water was added to mix to prepare a papermaking pollution inhibitor of the present invention in the aqueous solution.

Example 2

The performance of the papermaking antifouling agent prepared in Example 1 was investigated. In order to investigate the effect of precipitation prevention as one of the performance evaluation method, prepared CaCl ₂ and Na ₂ CO ₃ standard solution at 0.05 M concentration, the antifouling agent of Example 1 was added to the two standard solutions, mixed and heated to 40 ℃ The precipitate of the mixture was then filtered through filtrate. Thereafter, the amount of calcium ions remaining in the filtrate was titrated with 0.05 M EDTA standard solution. The end point was determined by the point where the solution changed from red to blue. Inhibition calcium (Inhibition power) (%) in the following formulas are shown in Table 5 below. The protection was expressed as 100% when calcium control was completed in solution.

[formula]

TABLE 5

Pollution inhibitor usage (ml) 0.05 0.1 0.15 0.2 0.25 0.3 Calcium protection (%) 33.4 50.1 64.3 69.2 75.4 90.2

The calcium hardness of the solution used was converted into CaCl ₂ in an amount corresponding to 2000 ppm of CaCO ₃ . As can be seen from Table 5, when 0.3 ml or more of the antifouling agent of the present invention is added, it can be seen that the calcium prevention is 90% or more, which can effectively suppress the scale even in a very small amount.

Experimental Example 2

In order to investigate the felt conditioning effect of the antifouling agent of Example 1, it was applied directly to a factory producing a board of 700 Ton / day. Field application conditions were that the anti-pollution agent of Example 1 was placed in the most contaminated pick-up felt for about 50 days while maintaining 400 ppm through a felt chemical shower to the existing intermittent acid. In addition, the alkali system was compared with the pollution level. The comparison results are shown in Table 6 below.

TABLE 6

1P upper felt contamination (wt%) 1P bottom felt contamination (wt%) Remarks Cleaning method Washing concentration Cleaning time When applying existing acid and alkali system 10.27% 7.93% Intermittent 0.5% 50 days When applying pollution inhibitor 5.60% 5.42% Continuous 400 PPM 50 days Pollutant removal rate (%) (relative to existing acid and alkali systems) 45.4% ↓ 31.6% ↓ - - -

As can be seen in Table 6, the continuous washing system using the anti-fouling agent of the present invention showed a superior washing effect compared to the acidic and alkaline intermittent washing system of the existing foreign products, and in the case of inorganic pollution, the washing effect was increased by more than 50%. Could see.

As mentioned above, the papermaking antifouling agent of the present invention suppresses the deposition of contaminants generated during the papermaking process, thereby increasing the productivity and improving the quality of the paper. In addition, it is possible to reduce the formation of scales in the pipes used in the papermaking process to prolong the service life of the facility, simplify the maintenance of the facility, and to apply the site in low concentrations during operation. It is possible.

Claims (6)

(Correction) characterized in that it comprises an organic acid having 5% to 60% by weight of carboxyl group, 5% to 30% by weight of phosphonate compound, 0.01% to 5% by weight of anionic surfactant and residual water Anti-fouling composition for paper. The papermaking antifouling composition according to claim 1, further comprising 0.1 wt% to 2 wt% polyacrylamide or 0.1 wt% to 3 wt% polyoxyethylene octyl phenylether. Antifouling composition. The method of claim 1, wherein the organic acid is a group consisting of glycolic acid, tartaric acid, lactic acid, levulic acid, succinic acid, and acetic acid. The antifouling composition for paper making, characterized in that at least one selected from. The method of claim 1, wherein the phosphonate compound is selected from the group consisting of HEDP (1-hydroxy ethylene-1,1-diphosphonic acid), ATMP (aminotrimethyl phosphonic acid) and a salt (Na) compound of the compound Anti-pollution composition for paper making, characterized in that. The papermaking antifouling composition according to claim 1, wherein the anionic surfactant is a sulfate of C ₁₂ to C ₁₈ higher alcohol. (delete)