The hottest rosin alkaline sizing agent is used to

Rosin alkaline sizing agent is used to produce high-grade writing paper

the length of the closing bearing plate is applicable to the requirements of the corner experiment. Key words: alkaline sizing pine 4. Filter: for the filter without the infarct instigator, the comprehensive cost of the strength retention rate of the fragrant paper

in order to use more secondary fibers and short fibers as raw materials for papermaking, and use alkaline filler calcium carbonate to reduce production costs, improve paper quality, reduce energy consumption, and reduce environmental pollution, Worldwide papermaking production has shifted from acidic to neutral. This paper introduces the situation of neutral sizing with domestic rosin alkaline sizing agent AS39 instead of soap size on 1760mm long paper machine in a factory

1 experimental overview

1.1 experimental machine and type: 1760mm long paper machine, speed 190m/min, quantitative 70g/m2 high-grade writing paper

1.2 raw materials for the experiment: pulp, 20% commercial pulp + 80% self-produced reed pulp; Filler, calcium carbonate: talc powder = 1:1; Alkaline sizing agent AS39, produced in Shanghai, with a lotion concentration of 40% and a storage period of 6 months; The starch retention aid is cationic starch; The polymer retention aid is Cationic PAM

2 results and discussion

2.1as39 effect of alkaline sizing agent on physical indexes of paper

see Table 1 for the comparison of process conditions and quality before and after replacing saponified size with AS39 alkaline sizing agent

it can be seen from table 1

Table 1 paper quality and manufacturing process before and after replacement

soap sizing acid sizing AS39 neutral sizing

quantitative (g/m2) 7070

tightness (g/cm3) 0.720.73

sizing (mm) 0.50.75

folding resistance (Times) 8.011.1

fracture length (km) 3.343.36

whiteness (%) 88.389.8

ash (%) 6.87.0

sizing agent (%) 1.00.4

dosage of alum (%) 5.00.8

the pH of the lower white water is 6.6 ~ 6.87.6 ~ 7.8

(1) under the condition that the pH value of the lower white water is 7.6 ~ 7.8, the dosage of AS39 is 0.4% (calculated by 100% solid conversion), the dosage of bauxite is 0.8% (calculated by solid), and the paper sizing degree can reach 0.75mm

(2) compared with soap glue near neutral sizing, AS39 sizing improves the sizing degree of the finished paper, especially the folding resistance of the finished paper is significantly improved (about 38%)

2.2 the influence of AS39 alkaline sizing system on the retention effect of fine fractions

see Table 2 and table 3 for the white water concentration and retention rate before and after replacing rosin soap size with AS39 alkaline sizing agent

white water analysis in Table 2 adopts CDC system 1 to collect the results of temperature testing instruments in the area under its jurisdiction

concentration ash filler content fiber content

(g/l) (%) (%)

soap glue 1.5030.1938.1661.84

AS39 1.1018.2822.8477.16

Table 3 filler retention rate before and after replacement

soap glue AS39

filler retention rate (%) 48.8873.45

filler ignition loss (%) 290129.26

fiber ash (%) 0.610.61

it can be seen from table 2 and table 3 that when AS39 is used to replace soap glue, the filler retention rate increases from 48.88% to 73.45%, the lower white water concentration decreases from 1.5g/l to 1.1g/l, and the loss of fine components in pulp decreases by 27%

2.3 effect of AS39 alkaline sizing agent on production cost

when AS39 alkaline sizing agent is used to replace soap sizing, the sizing cost increases slightly, but due to the reduction of material loss, the comprehensive production cost per ton of paper decreases by about 115 yuan (calculation omitted)

3 conclusion

through this test, the following conclusions are drawn: 3.1 compared with the original soap glue, what are the functional characteristics of the digital seat belt tension tester using AS39? After neutral sizing, the folding resistance of the paper is increased by 38%. This is of special significance for paper based on straw pulp

3.2 after replacing saponified gum with AS39 rosin alkaline sizing agent, the comprehensive cost per ton of paper is reduced by about 115 yuan due to the reduction of material loss, and its economic benefit is significant

3.3 the conditions for alkaline sizing with AS39 in the plant are as follows: AS39 0.4%, bauxite 0.8%, cationic starch 0.6%, PAM 0.03%; Lower white water pH 7.6 ~ 7.8

to sum up, AS39 alkaline sizing system can not only improve the retention rate of fine components in pulp, but also improve the strength of paper; It can not only improve the quality of paper, but also reduce the production cost, but also reduce the pollution load of wastewater. In addition, after changing from acid sizing to neutral sizing, it will also reduce equipment corrosion and pipe scaling, so as to reduce operating obstacles such as roller sticking and paper breaking, as well as downtime and cleaning time. ■