This study aimed at evaluating effect of sizing agent and various fillers on properties of printing and writing paper. Therefore, sizing agent (AKD) in 1.5% level and fillers including precipitated calcium carbonate (PCC), ground calcium carbonate (GCC) and Obtained from Water Treatment Process (SCC)in 30% level were applied based on dry weight of fibers in furnish consisted of 80% chemical-mechanical pulp (CMP) of hardwood and 20% bleach softwood kraft pulp (BSKP) according to TAPPI Standard. In order to investigate the effect of sizing agent and various fillers, papers with 60 g/m2 basis weight were produced from each treatment. Results showed that the dimensional properties of calcium carbonate species is effective on strength properties of paper. Of the three types of ground calcium carbonate (GCC), precipitated (PCC) and softening calcium carbonate (SCC), precipitated calcium carbonate due to smaller particles cause a further reduction in paper strength and Calcium carbonate from water softening due to the larger particles, had a minimal impact in reducing the paper strength properties. Paper filled with precipitated calcium carbonate has an intermediate strength properties of paper filled with precipitated calcium carbonate and softening calcium carbonate.

purification and softening, a lot of calcium carbonate with other impurities produce and these byproducts gather and bury as mineral sludge.In this research, The quality of calcium carbonate from water softening process in mazandran wood and paper industry (MWPI) mill and effects of loading of this byproduct on fine paper production was investigated and the results were compared with other industrial fillers like grounded calcium carbonate(GCC) and precipitated calcium carbonate(PCC) and also china clay (kaolin).From the paper structural viewpoint, the fine paper that filled with water softening calcium carbonate (derived after water softening process) have more bulk(bulkier) and more porous and rougher surface compare to fine papers that filled with the common industrial fillers.From the paper strength properties viewpoint, the fine paper that filled with water softening calcium carbonate have less decrease in tensile and burst strength but have not suitable tear strength properties. From the paper optical properties viewpoint, the fine paper that filled with water softening calcium carbonate, because of particles size and impurities of this filler have the least light scattering coefficient and consequently have less brightness and opacity.Adding of 10 and 20 percent precipitated calcium carbonate to by water softening calcium carbonate cause paper porosity and strength decreasing but the optical properties of hand sheets was increased.

As a result of water treatment and during the water softening and hardness reducing process, calcium carbonate deposits with other impurities produced, collected and buried as mineral sludge. This study was done to investigate the effect of using calcium carbonate filler (as a byproduct of water treatment process in Mazandaran wood and paper mill) on strength properties of fluting paper produced from both old corrugated container (OCC) and neutral sulfite semi chemical(NSSC) pulps. Calcium carbonate added to the pulps at levels of 5, 10 and 15 percentage of bone dry weight of paper. The air resistant with the tensile index, burst index, tear index and resistant to fluting of handsheets were measured and compared to control handsheets (samples without calcium carbonate). The results showed that the use of calcium carbonate from the water treatment has a negative impact on fluting paper strength properties. Calcium carbonate filler negative impacts on virgin pulp (NSSC) and recycled pulp (OCC) is different and is more in OCC pulp.

Bacteria attachment to soil is an important component in bacteria transport models. The objective of this study was to quantify the influence of calcium carbonate on bacteria attachment anddetachment in calcareous soil. Consequently, 60 calcareous soil samples were collected from Central Province and their bacteria (Escherichia coli) adsorption isotherm, physical and chemical properties were measured. Three types of adsorption isotherms were evaluated. The results indicated that linear isotherm leads to a better prediction of bacteria attachment to calcareous soil in comparison with the Freundlich and Langmuir isotherms. A pedotransfer function was also derived to predict the kd parameter of the linear isotherm from soil particle size distribution and calcium carbonate content. The attachment and detachment of bacteria in three treatments of calcium carbonate content (10, 21 and 37%) were tested in a completely randomized design (CRD) with three replications. According to the results, increasing soil calcium carbonate content leads to enhanced equilibrium and kinetic bacteria attachment (p<0.05). Bacteria detachment also decreases by increasing soil calcium carbonate (p<0.05).

Aim of this study is precipitated calcium carbonate cationic modification and comparison of impact of using its with conventional filler (unmodified) on strength properties of paper. One of the defects of adding fillers to paper is decreasing of mechanical strength of paper because of reduction in bonding area between fibers. In this study whit purpose of maintaining the strength of paper، and change the surface charge of precipitated calcium carbonate and replace it with conventional fillers are used. in this research with aim of precipitated calcium carbonate and replacing it with conventional filler was used. Condition of cationic precipitated calcium carbonate preparation was 90 ċ temperature، 3 hours time and 55% water content of cooking process. loading amount of starch was 9، 12 and 15 percent based on precipitated calcium carbonate weight. Papers made at three level: 10، 16، 30 percent of filler in paper sheets contain conventional fillers were compared. Results indicated that papers containing modified-filler have more values of retention rather than those with unmodified filler، both in 20% and 30% filler dosages. papers contained cationic filler have more mechanical strength index in respect of papers contained conventional fillers.

In this study، the effect of using different amounts of zeolite and calcium carbonate fillers at three levels comprising 10، 20 and 30 % on newsprint paper properties was investigated. Chemi Mechanical Pulp (CMP) and calcium carbonate and zeolite fillers (Analysm type) were used. To compare the physical and mechanical properties، from equal amount of filler remaining in paper as 10% zeolite and 30% calcium carbonate treatments was used to interpretation of results. The results showed that zeolite retention (59. 17%) is more than calcium carbonate (22. 5%). Important result of this research is to reduce production costs and effluent pollutions due to high retention of zeolite filler. Papers containing 10% zeolite in comparison with 30% calcium carbonate fillers، physical and mechanical properties were more but brightness and opacity were less. Totally، it can be concluded that zeolite filler is suitable for products that moderate brightness needs.

Calcium carbonate is a versatile mineral with diverse industrial applications. Drying is a necessary processing step in preparation of calcium carbonate product. Deep knowledge of drying kinetics is required in order to design an appropriate dryer. The main aim of the present study was to investigate the drying kinetics of calcium carbonate, experimentally. Thirteen empirical correlations with temperature-dependent constants were used to describe the thin-layer drying behavior of calcium carbonate. The correlation fitting results revealed that all examined empirical correlations were acceptable. But, the Page correlation was in the best agreement with experimental data. The effective moisture diffusivity was calculated within 8.61 × 10-9 to 10.40 × 10-9m2s-1 in the temperature range of 60 to 90˚C. The drying activation energy was also calculated to be 6.306 kJmol-1. The fitted correlations for the drying kinetics of calcium carbonate can be used to design an industrial dryer and also to estimate drying time in various drying conditions.

The study is carried out to survey the effect of using cationic polymers for cationization of precipitated calcium carbonate (PCC) synthesis’s suspension on paper properties.
Paper is made by lignocellulosic material and inorganic compounds. Inorganic compounds are including functional additives and process aids which mineral fillers belong to functional additives. Todays, due to shortage and high price of lignocellulosic raw material, papermakers raised the consumption of mineral fillers. However, mineral fillers though have numerous advantageous like improvement in optical properties, printability, reduce production costs, also induces disadvantageous like weak distribution in paper structure, loss of mechanical properties, less retention, instability of production line and increasing effluent pollution loading.
Singh et al (2011) optimized the application of chemicals for high yield papers using PCC thereby starch and silica. They claimed that cationic starch with medium cationic charge induces highest retention value, while cationic starch with high charge density results in most drainage.
Studies by Shen et al (2010) showed that modified-PCC with carboxyl methyl cellulose (CMC) / alum improved filler retention and also optical properties like brightness and opacity in comparison with control sample significantly. They also found that paper without mineral filler have higher strength than those have fillers, but mechanical strength of paper contained unmodified filler and paper contained modified filler hadn’t significant difference.
Eventually, considering issues like production cost, effluent and its pollution loading, enhancement of paper machine speed, and also necessity of production paper with appropriate formation and quality, it’s necessary to study the interactions of various additives in paper, depending on their application.
Material and Synthesis of PCC carried out by injecting the carbon dioxide (CO2) to lime solution, or releasing the CO2 thereby hydrolysis of di-methyl carbonate in alkaline media. Cationic polymers including cationic starch, polyacrylamide, poly amino polyamide-epichlorohydrin and polydadmac in 15% level were used in synthesis suspension of calcium carbonate. Finally, paper properties filled with modified-PCC were examined.
It’s found that cationic suspension of different polymers lead to variation on synthesized calcium carbonate as papermaking filler. Generally, papers filled with modified-PCC compared with papers contained industrial calcium carbonate and those had synthesized calcium carbonate, improved optical and mechanical properties in neutral media except tear strength.
In this study, values of ash in papers contained modified calcium carbonate increased compared with papers with industrial calcium carbonate and those with synthesized calcium carbonate in neutral media. Bulk of papers with modified fillers reduced, but the air resistance, tensile and burst strengths and also optical properties increased. Normally, since mineral fillers have no bounding ability with cellulose fibers, so due to restricted and weaker bonds between fibers and also lack of appropriate formation and lack of stress distribution as a result, tensile and burst indices of paper decreased respectively. However, by synthesizing calcium carbonate in cationic suspension, because of improved bounding area induced by presence of cationic polymers in surface of precipitated calcium carbonate and uniform distribution of mineral filler in paper different response found.

Cementation of soil using calcium carbonate precipitation or MICP is a new biologic method of soil improvement. In this research, this method was used to improve the strength of copper mine tailing slurry. It has been performed by carbonate producer microorganisms, which by adding the appropriate calcium source, cause sedimentation or biocementation in the environment. The resulting calcium carbonate has a significant effect on the soil strength. In this study, a bacterium called Sporosaurina Pasteurium and a microalga called Chlorella Suloxanase, have been used. Optimization of the calcium carbonate formation in the presence of the most suitable calcium chloride concentration and the best temperature for the reaction has been evaluated. The calcium carbonate was injected into the specimen and the sample strength was determined by unconfined compression tests. After biological treatment, the unconfined strength of the slurry increased up to 3 times for saturated state and 7 times for the dry condition which proved the successful treatment using biological method.

Chemical clogging can reduce geotextile permeability and obstruct drainage system. Calcium carbonate is a substance of low solubility which precipitates rapidly and forms the hard pan layer which results in clogging the drain envelope. The study was done on drain envelope in Abadan palm grove showed calcium carbonate was the main precipitated chemical in drain envelops. Laboratory column filter tests were conducted to simulate calcium carbonate precipitation on geotextile. Experiments performed with three types of geotextile including woven and nonwoven types. The result show that carbonate calcium precipitation decrease the ability to percolate water through the geotextile. Calcium carbonate precipitation was collected at an aerated/non-aerated interface in the filters and surrounded the fibers as a layer. Chemical precipitation in geotextile cover surrounds the fibers and increase thickness with time. Hydraulic conductivity was decreased about 30 percent by chemical precipitation. Results also show that according to laboratory conditions, clogging time for two kind of nonwoven geotextile is 4 and 6 years.