Fines Retention Research Articles

Recyclability of wastepaper containing cellulose nanofibers

Cellulosic/lignocellulosic nanofibers (CNF/LCNF) are value-added products which recently have been considered widely. This study focused on valorization of waste by making CNF from white cutting wastepaper (WCW), which was confirmed by the transmission electron microscope images. The CNF present in the paper recycling process showed significant effects on the final product and process aspects. Addition of 5% CNF (based on dry weight of pulp) to the recycled fibers improved the strength properties as well as the fines retention. But in contrast, the drainage decreased from 303 to 188 mL CSF. Finally, considering the importance of wastepaper history on the quality of recycling process and final products, as a new vision, this study focused on recyclability of wastepaper which has experienced CNF as an additive in their history of papermaking. In this respect, the papers reinforced with nanofibers in their history, after several recycling, experienced less reduction in the tensile and tear indices and fines retention. In summary, it seems that the presence of CNF in the wastepaper can slow down the reduction of product density and process properties during several recycling cycles and so restore their potential for subsequent papermaking cycles.

Dynamic modelling of reservoir fines retention by mesoporous silica nanofluid to improve oil recovery during low salinity water flooding of a consolidated sandstone

Mesoporous silica (SiO2) nanoparticles (MSNP) was used to stabilize formation fines for increased oil recovery during low salinity water flooding. Likewise, the effect of porous media length on dynamic retention of fines at high temperature reservoir condition was investigated. Breakthrough curves of reservoir fines adsorption by mesoporous SiO2 nanofluid (MSNF) were described using Thomas and Yoon-Nelson models. Similarly, effect of concentration, flow rate, porous media length and temperature on the retention capacity of reservoir fines was modelled using Box Behnken design of experiments. Subsequently, effect of reservoir fines stabilization on oil recovery was evaluated. Formation damage remediation propensity of MSNF was investigated. Finally, the oil recovery mechanisms were determined using the sessile drop contact angle and Wilhelmy plate methods. Experimental results of the dynamic adsorption with coefficient of determination (R2) values between 0.967 and 0.999 signifies that the reservoir fines adsorption by MSNF were well predicted by Thomas and Yoon-Nelson models. Consequently, MSNF stabilized the reservoir fines by attaching onto their surface rather than on the porous media thereby changing the wettability to water-wet, decreasing the contact angle to 16.1°, 17.1° and 20.7° for kaolinite, illite and montmorillonite, respectively. Thus, increasing oil recovery by 22–23% original oil in place.

Filtration Performance of Nonwoven Geotextile Filtering Fine-Grained Soil under Normal Compressive Stresses

To avoid serious clogging and loss of drainage capacity, which puts the underground structure at risk of anti-floating failure, the buried drainage filter must be equipped with a nonwoven geotextile layer. In this scenario, nonwoven geotextiles are subjected to normal compressive stress, which can cause changes in geotextile porosity and structure, affecting the filtration behavior of the geotextile filter. In this paper, in order to evaluate the filtration compatibility of the soil–geotextile system, gradient ratio (GR) tests were performed under a hydraulic gradient of 1.0 using a specially designed gradient ratio filtration device capable of applying normal stress. In total four nonwoven geotextiles and two types of soil were used. The results of the gradient ratio filtration tests were discussed in terms of GR values, the permeability of the soil–geotextile system, and the amount of fines retained in geotextiles. It was shown that under a larger normal compressive stress, the GR value would also increase, while the permeability coefficient of the soil–geotextile system decreased. The filtration responses to various soil–geotextile combinations differed under normal compressive stress. A thick nonwoven geotextile with a small filtration opening size exhibited poor filtration performance while benefiting soil retention. Fines retention was influenced by geotextile thickness, soil type, and normal compressive stress magnitude. In addition, for nonwoven geotextiles filter fine-grained soil under normal compressive stress, the test results indicated that anticlogging design criteria should be improved.

METHODS OF PREPARATION OF NANOFIBRILLATED CELLULOSE FOR SPECIAL FILTER PAPERS WITH EFFECTIVE AIR FILTRATION. SHORT NOTES

Nanofibrillated cellulose was prepared from distillery refuse based on maize starch using the extraction with NaOH and HCl involving centrifugation. SEM images of bleached kraft pulp with/without the addition of nanofibrillated cellulose were compared. Theresults showed that the application of nanofibrillated cellulose caused a visible reduction in the surface porosity. Conversely, mixing of the pulp with the nanofibrillated cellulose resulted in large pores among the fibres. The effect of the cationic retention aid on porosity was not significant, observed in the fines retention. A minimal difference in porosity was found among of fine and coarse fibres.When lyophilisationas drying method was used it yielded nanofibrillated cellulose with a size in the range of approximately 100 to 150 nm.

The reduction of FCCU afterburning through process optimization and regenerator revamping

Operating the fluid catalytic cracking unit (FCCU) in afterburning conditions can increase the regenerator temperatures above the metallurgical design leading to mechanical failures of the cyclones and plenum chamber. This paper presents the methodology applied in a commercial FCCU to investigate the afterburning causes and the technical solutions that can be implemented to reduce the afterburning. Thus, by evaluating the regenerator temperature profile, regenerator as-build design, and the internals mechanical status, it was concluded that the main cause of afterburning was the non-uniform distribution and mixing of air and catalyst. The industrial results showed that optimizing the catalyst bed level, stripping steam, reaction temperature, and equilibrium catalyst (e-cat) activity reduced the afterburning by 39%. Other process parameters such as feed preheat temperature, slurry recycling, and excess oxygen did not significantly influence afterburning because of air and catalyst maldistribution. Revamping the regenerator to assure a symmetrical layout of cyclones reduced the afterburning by 86%, increased the fines retention in FCCU inventory, and provided a better regeneration of the spent e-cat. The reduction of operating temperatures at around 701?C removed the risk of catalyst thermal deactivation, and therefore the e-cat activity was increased by 10.2 wt.%.

Effects of Proppant Wettability and Size on Transport and Retention of Coal Fines in Saturated Proppant Packs: Experimental and Theoretical Studies

Hydraulic fracturing is the main stimulation technique that enables the economic production of coalbed methane reservoirs. However, massive invasion and retention of coal fines in proppant packs can clog the pore spaces and lead to an impairment of fracture conductivity. In this study, the effects of proppant wettability and size on retention of coal fines in proppant packs during the dewatering stage were investigated, for their optimization to achieve a long-term and effective control of fines retention. First, a series of transport and retention experiments of coal fines were performed on saturated proppant packs with different proppant sizes and wettabilities. Herein, standard quartz sand was used as the proppant carrier, and its surface wettability was modified to either hydrophobicity or stronger hydrophilicity by treatment with fluorocarbon resin and piranha solution, respectively. The experimental results indicated that both the retained amount and the deposition rate coefficient of coal fines decreased with increasing proppant hydrophilicity (or decreasing proppant hydrophobicity) and size. For the proppants treated with piranha solution, almost no coal fines were retained in proppant packs. Second, the forces/torques acting on coal fines in the vicinity of proppants were analyzed to elucidate the underlying mechanisms responsible for the influence of proppant wettability and size on fines retention. The effective filter surface (EFS) parameter was estimated by analyzing forces/torques to evaluate the filtration performance of proppant packs. Theoretical results illustrated that the EFS value decreased with increasing proppant hydrophilicity and size. The EFS value for proppants treated with piranha solution was near zero, which was due to the chemically “unfavorable” retention condition induced by piranha solution treatment. The EFS exhibited a similar tendency to the retention of coal fines observed in experiments, which validated the model. Finally, the recommendations on fines retention control in proppant packs were provided.

Selective addition of C-PVAm to improve dry strength of TMP mixed tissue paper

Abstract During the manufacture of low basis weight tissue paper, it is difficult to efficiently use the dry strength agent (DSA) because a large amount of DSA adsorbed fines releases in forming roll by centrifugal forces. In this study, cationic polyvinylamine (C-PVAm) was used as a DSA in an environment where the retention of fines was weak. Addition of C-PVAm to the thermomechanical pulp (TMP) or TMP mixed with softwood bleached kraft pulp (SwBKP) improved the turbidity of filtrate from sheet former, however, the strength of handsheet paper was similar to that without C-PVAm. When C-PVAm was selectively added to SwBKP as much as 4 %, the tensile index could be improved by approximately 10.6 % without changing the retention of fines. In addition, C-PVAm added before the beating of SwBKP showed better results than C-PVAm added after the beating in terms of fines retention, tensile index, and formation. In particular, the tensile index was improved about 7.7 % by adding of C-PVAm 4 % as is before beating of SwBKP. Consequently, it was found that C-PVAm with a high reaction rate can be added before beating of SwBKP to improve the physical strength.

The use of a PAE /bentonite binary system to improve the wet strength of paper

Bentonite and polyamidoamine epichlorohydrin (PAE) resin were added sequentially as a binary system to improve the properties of the paper, especially the wet strength. The results showed that the dry tensile index, the wet tensile index, and the folding endurance of the paper could be improved with only the use of polyamide polyamine epichlorohydrin resin. However, a binary system of polyamide polyamine epichlorohydrin resin and bentonite was more effective. When 0.8% polyamide polyamine epichlorohydrin resin and 0.75% bentonite were added, the dry tensile index, the wet tensile index, and the folding endurance of the paper increased by 37.8%, 2780%, and 281%, respectively, when compared to the control sample. The measurements of the water retention value and the percent fines retention of the pulp showed higher values after being treated with the binary system than being treated by polyamide polyamine epichlorohydrin resin alone. Scanning electron microscopy analysis indicated that a binary system of polyamide polyamine epichlorohydrin resin and bentonite could increase the combination of fibers in paper.

Development of Nanofluids for the Inhibition of Formation Damage Caused by Fines Migration: Effect of the interaction of Quaternary Amine (CTAB) and MgO Nanoparticles.

Fines migration is a common problem in the oil and gas industry that causes a decrease in productivity. In this sense, the main objective of this study is to develop nanocomposites based on the interaction of quaternary amine (hexadecyltrimethylammonium bromide—CTAB) and MgO to enhance the capacity of retention of fine particles in the porous medium. MgO nanoparticles were synthesized by the sol–gel method using Mg(NO3)2·6H2O as a precursor. Nanoparticles were characterized by dynamic light scattering (DLS), the point of zero charge (pHpzc), thermogravimetric analysis, and Fourier transform infrared spectroscopy (FT-IR). Different nanoparticle sizes of 11.4, 42.8, and 86.2 nm were obtained, which were used for preparing two system nanofluids. These systems were evaluated in the inhibition of fines migration: in the system I MgO nanoparticles were dispersed in a CTAB-containing aqueous solution, and system II consists of a nanocomposite of CTAB adsorbed onto MgO nanoparticles. The fines retention tests were performed using Ottawa sand 20/40 packed beds and fine particles suspensions at concentrations of 0.2% in a mass fraction in deionized water. Individual and combined effects of nanoparticles and CTAB were evaluated in different treatment dosages. The analysis of the interactions between the CTAB and the MgO nanoparticles was carried out through batch-mode adsorption and desorption tests. The best treatment in the system I was selected according to the fines retention capacity and optimized through a simplex-centroid mixture design for mass fractions from 0.0% to 2.0% of both CTAB and MgO nanoparticles. This statistical analysis shows that the optimal concentration of these components is reached for a mass fraction of 0.73% of MgO nanoparticles and 0.74% in mass fraction of CTAB, where the retention capacity of the porous medium increases from 0.02 to 0.39 mg·L−1. Based on the experimental results, the nanofluids combining both components showed higher retention of fines than the systems treated only with CTAB or with MgO nanoparticles, with efficiencies up to 400% higher in the system I and higher up to 600% in the system II. To evaluate the best performance treatment under reservoir conditions, there were developed core flooding tests at fixed overburden pressure of 34.5 MPa, pore pressure at 6.9 MPa and system temperature at 93 °C. Obtaining critical rate increases in 142.8%, and 144.4% for water and oil flow in the presence of the nanofluid. In this sense, this work offers a new alternative for the injection of nanocomposites as a treatment for the problem of fines migration to optimize the productivity of oil and gas wells.

Stable Dispersion of Coal Fines during Hydraulic Fracturing Flowback in Coal Seam Gas Reservoirs—An Experimental Study

In subterranean coal seam gas (CSG) reservoirs, massive amounts of small-sized coal fines are released during the production and development stages, especially during hydraulic fracturing stimulation. These coal fines inevitably cause mechanical pump failure and permeability damage due to aggregation and subsequent pore-throat blockage. This aggregation behavior is thus of key importance in CSG production and needs to be minimized. Consequently, such coal fines dispersions need to be stabilized, which can be achieved by the formulation of improved fracturing fluids. Here, we thus systematically investigated the effectiveness of two additives (ethanol, 0.5 wt % and SDBS, 0.001 and 0.01 wt %) on dispersion stability for a wide range of conditions (pH 6–11; salinity of 0.1–0.6 M NaCl brine). Technically, the coal suspension flowed through a glass bead proppant pack, and fines retention was measured. We found that even trace amounts of sodium dodecyl benzene sulfonate (SDBS) (i.e., 0.001 wt %) drastically improved dispersion stability and reduced fines retention. The retention was further quantified by fractal dimensional analysis, which showed lower values for suspensions containing SDBS. This research advances current CSG applications and thus contributes to improved energy security.

A novel approach for using silica nanoparticles in a proppant pack to fixate coal fines

Hydraulic fracturing operations in coal seam gas reservoirs are highly prone to release coal fines. Coal fines inevitably cause mechanical pump failure and permeability damage as a result of their hydrophobicity, aggregation in the system and pore-throat blockage. One approach to affix these coal fines at their source, and to retard generation, is to introduce a nanoparticle-treated proppant pack. Thus, this research explores coal fines retention (known as adsorption) in a proppant pack using nanoparticles. In the study, the electrolytic environment, pH, flow rate, temperature and pressure were kept constant, while the variables were concentration of silica nanoparticles (0–0.1 wt%) and coal fines concentration (0.1–1 wt%). The objective was to identify silica nano-formulations that effectively fixate coal fine dispersions. Subsequently, the coal suspensions flowed through a glass-bead proppant pack treated with and without nanoparticles, and were then analysed via a particle counter. The quantitative results from particle counter analysis showed that the proppant pack with nanoparticle treatment strongly affected the fixation ability of coal fines. The proppant pack without nanoparticle treatment showed up to 30% adsorption and flowed through the proppant untreated, while proppant pack treated with nanoparticles showed up to 74% adsorption; hence, more exceptional affixation ability to the coal fines. Further, the results indicated that the zeta-potential of silica nanoparticles at higher salinity became unstable, i.e. approximately –20 mV; this low value helped the proppant pack treated with nanoparticles to attach coal fines to it. The ability of nanoparticles to adsorb coal fines is due to their highly active surface, and high specific surface area.

Effects of fines migration on oil displacement by low-salinity water

Enhanced oil recovery by low-salinity waterflooding (LSW) has been shown to result from the combined effect of various physical mechanisms. In this study, laboratory experiments were designed in such a way that only fines migration mechanism remains active. Then, experimental observations and detailed characterizations of core plugs and produced fluids (water and oil) were used to analyze the effect of fines migration-induced formation damage on displacement efficiency. In the first set of experiments, core plugs of Berea and Obernkirchener sandstones were subjected to single-phase injections of water at salinities 40, 30, 20, 10, 5, 2.5, 0.5 and 0 g/L NaCl. An order-of-magnitude decrease in permeability was observed for both core plugs and was associated with an increase in fines concentration in the produced water. SEM-EDS images of the produced fines showed that kaolinite is mobilized as the salinity is reduced. SEM images of the pores before and after injection also showed fines retention and blockage.In the second set of experiments, two-phase LSW was performed on a pair of core plugs comparable to those in the first set of experiments. Kaolinite migration results were consistent with those of single-phase LSW. The two-phase LSW experiments showed 50% reduction in water relative permeability and 3% increase in oil recovery. Because no wettability alteration mechanism was active, the increase in oil recovery is attributed solely to enhanced displacement due to fines migration.

Using nanofluids to control fines migration for oil recovery: Nanofluids co-injection or nanofluids pre-flush? -A comprehensive answer

This paper provides a comprehensive study to evaluate and optimize the effectiveness of nanofluids to both prevent fines migration and enhance oil recovery using different utilization approaches: nanofluids co-injection and pre-flush. To do that, 1) a comprehensive review of both laboratory experiments and field cases is adopted to confirm the effectiveness of nanoparticles to control fines migration. 2) A novel model of maximum fines retention concentration is then introduced to find out the physical mechanisms on how nanoparticles control fines migration. 3) Through matching with lab experiments, the physical behaviors of fines migration and attachment with the effects of different types of nanofluids are characterized, including fines attachment and straining rates, and breakthrough time of injected fines. 4) As a new criterion, mitigation index (MI) is defined to find out the more excellent performance of nanofluids pre-treatment that of nanofluids co-injection. 5) The pros and cons of fines migration on performance of low-salinity water flooding are discussed comprehensively, in this work, and the success of combining nanofluids with low-salinity water flooding is also confirmed to achieve more oil recovery. The outcomes of this work will help extend the applications of nanofluids in reservoirs suffering from problems of fines migration.

Preparation of Cationic CMP and Softwood Long Fibers as Strength-Enhancing Additive to CMP Pulp

Compared to chemical pulp, mechanical and chemi-mechanical pulps (CMP) are limited in regards to the manufacturing of high quality paper. Chemical additives are an effective way to enhance the properties of paper; however, the effectiveness depends on the additive type and dosage. The utilization of cationized natural polymers has been shown to offer a promising solution. In this study, softwood long fiber (SLF) and CMP were cationized by 3-chloro-2-hydroxypropyl-trimethylammonium-chloride (CHPTAC), and the effects of cationization on the properties of CMP pulp were studied. Cationization was characterized by FTIR and the nitrogen content, and its effect on the CMP properties was evaluated through mechanical tests and fines retention. Cationization at low and moderate levels and in higher mixing rates improved the mechanical properties of CMP. Compared to cationized CMP, the addition of cationized SLF (CLF) improved the strength and fines retention properties. The CLF application to CMP at a CHPTAC dosage of 5% increased the tensile, burst, and tear strengths by 66.4%, 100%, and 3.6%, respectively. The cationized SLF increased the fines retention by 12.7%.

Compositional modeling of nanoparticle-reduced-fine-migration

During waterflooding, formation fines migration is a recognized reason for well injectivity and productivity reduction in sandstone reservoirs. Permeability decrease due to fines migration is one of the major issues in the application of low salinity enhanced oil recovery techniques. Recently, nanoparticles injection is found to reduce the fines release in sandstone cores through adsorption on the pore surface. In this research, a numerical model is developed to explore the coupling processes of nanoparticle transport, fine attachment and release, aqueous species reactive transport, and multiphase flow.Components including oil, water, salt, fine particles and nanoparticles are considered in this model. Both fluid dynamics and physical interactions are integrated in the coupled simulation approach. The nanoparticles exist in aqueous phase during injection, and can be attached to the solid surfaces to decrease surface energy. The formation fines can be suspended in aqueous phase, or retained by pore throats that decrease the permeability. The fines retention is modeled as a dynamic process where the retention rate is a function of salinity, nanoparticle adsorption, and flow velocity. The wettability alteration due to nanoparticle and low salinity is also included. A compositional simulator is developed based on implicit pressure explicit composition to include the detailed mathematical description of the complex processes.This paper provides detailed procedures of building a nanoparticle and fines transport and interaction model. To calibrate the diffusion/dispersion and adsorption isotherm constants, lab core flow experiments with nanoparticle injection are simulated. The fines migration experiments are simulated with and without nanoparticle injection at varying salinity. Simulation results demonstrate that the nanoparticle injection can effectively reduce the fine release and prevent permeability decrease at different salinity. In addition, the heterogeneous field scale simulation was performed. The oil recoveries with and without nanoparticle injection are compared for low salinity water injection. The simulation results indicate that using nanoparticles in low salinity waterflooding can improve oil recovery with mitigated formation damage.This work demonstrates a compositional model that can be used to simulate nanoparticle technology enhancing waterflooding performance. It is believed to be the first numerical model that explicitly includes the nanoparticle transport and its effect on fines migration. This paper will improve the understanding of geochemical conditions and spatial distribution of fines retention and whether the sweep efficiency will be improved.

A comprehensive understanding of saturation index and upflow velocity in a pilot-scale fluidized bed reactor for struvite recovery from swine wastewater

Fluidized bed reactor (FBR) has been applied in phosphorus recovery from wastewater due to its ability on producing struvite pellets with large size, high crushing strength and purity. However, the fine struvite crystals (fines) can be flushed out of the reactor, which may result in undesirable and variable phosphorus recovery efficiencies. In this study, the influences of key factors with respect to phosphorus recovery and product quality in a FBR were investigated for the treatment of swine wastewater. The effects of process parameters were first evaluated using response surface methodology (RSM), and later, long-term pilot-scale operations were tested. Results showed that fines retention was directly related to the in-reactor saturation index (SI) and upflow velocity (vup). Decreasing SI (from 2.42 to 1.65) or vup (from 75 to 25mms−1) will reduce the fines entrainment and improve the phosphorus recovery profile by 14.9 and 18.5%, respectively. Moreover, these two factors governed the quality of the struvite pellets in the pilot-scale investigations—SI showed more crucial effect to size distribution, crushing strength and morphology than vup. As to the composition, struvite (35.5–95.3% of mass fraction) and CaCO3 (2.8 to 51.4% of mass fraction) were the two major components in the pellets. Decreasing SI or increasing vup and pellet size can enhance the struvite purity. Therefore, phosphorus recovery and pellet quality can be simultaneously improved by SI and vup control without additional trapping devices or reagents. The finding is constructive for FBR system set-up and operation in either pilot- or full-scale applications, where different phosphorus recovery rates and product qualities are required.

Effects of Inorganic Coagulants on Sizing and Contamination in Newsprint Mill

For some Korean newsprint mill, addition level of aluminum sulfate has been reduced because sulfur from aluminum sulfate has detrimental effect on the efficiency of anaerobic water treatment. At this moment, an unexpected decrease in sizing degree of TMP mixed newspaper was occurred. The phenomena means that hydrophobic substance usually originated from TMP cannot be fixed on the paper. This study focused on effect of alum and PAC on sizing of paper and contamination. Also, substitutability of PAC was discussed as a possible alternatives of aluminum sulfate under anaerobic condition of water treatment. Evaluation of sizing degree and pitch deposit potential were performed at the varied addition level of PAC and aluminum sulfate. Hydrophobic substance mainly derived from TMP could be fixed on the surface of fiber by PAC. Fines retention was not changed by replacing aluminum sulfate with PAC. Additionally, fixing of hydrophobic substance without excessive agglomeration can be enhanced by PAC with low molecular weight. Consequently, sizing degree of newspaper and contamination of recycling process of ONP can be controlled by low molecular weighted PAC.

TEMPO/NaBr/NaClO-Mediated Surface Oxidation of Nanocrystalline Cellulose and Its Microparticulate Retention System with Cationic Polyacrylamide

TEMPO/NaBr/NaClO-mediated surface oxidation of NCC, acid-extracted from aspen kraft pulp, was studied, and the properties of nanocellulose whiskers before and after oxidation were characterized by conductimetry, Fourier transform infrared spectroscopy, X-ray diffraction, and atomic force microscopy. The resulting products with varied oxidation degrees were then applied in the deinked pulp to evaluate the improvements of fines retention and pulp drainage. It was found that TEMPO-oxidized NCC maintained its crystalline form of cellulose I, while it showed better dispersibility and smaller dimension due to the high level of carboxyl content and degree of oxidation. By adding NCC and TONCC to the deinked pulp, the retention was improved while the drainage rate was decreased to some extent. When TONCC samples were applied together with cationic polyacrylamide to constitute a microparticulate retention system, both fines retention and pulp drainage were apparently improved. Further study showed that the retention and drainage rate were significantly influenced by the degree of oxidation. TONCC sample with the highest DO (0.134) gave the highest retention and drainage rate, 89.6% and 9.41 mL/s, respectively.

Surface Modification of Nanocrystalline Cellulose and its Application in the Deinked Pulp

In this study, nanocrystalline cellulose (NCC), isolated from the bleached aspen kraft pulp, was surface modified using borate. The resultant nanocrystal suspensions, namely B-NCC, were characterized by conductometric titration and atomic force microscope (AFM). B-NCC was then applied as a retention aid in the bleached old newsprint deinked pulp. The results showed that the modification process led to a negative increase in surface charge density, while the particle size was not changed. The fines retention and pulp drainability were increased when the B-NCC was used either alone as the monocomponent retention aid, or together with cationic polyacrylamide (CPAM) to constitute a microparticle retention system. The microparticle retention system gave better retention and drainage rate, with the maximum values of 90.5% and 3.5 ml/s, respectively.

A novel method for the determination of linting propensity of paper

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.