De-inking Residue Research Articles

Green Materials: Adhesive Properties of Bio-oils Derived from Various Biorenewable Waste Streams: From Wood to Paper to Paper Deinking Residue

Making innovative use of low-value and underutilized biorenewable waste streams, and the unavoidable losses resulted from industrial practices, is crucial for transitioning from a petro- to a biobased economy in the 21st century. This study provides a holistic and comprehensive overview of the adhesive properties of bio-oils generated from microwave-assisted low-temperature (<200 °C) pyrolysis of three biorenewable wastes: spruce wood chips, waste paper, and paper deinking residue (DIR). The spruce wood chips and waste paper derived bio-oil could bond two Al plates with high tensile strengths generally. Highest tensile strengths around 2520 N were reached with the spruce wood chips derived bio-oil. The ATR-IR and solid-state CP/MAS 13C NMR characterization of the bio-oil polymer scrapings reveal that the bio-oil possibly undergoes homo- and/or cross-coupling reactions during curing. A model compound study using 5-hydroxymethylfurfural (HMF), levoglucosan, and catechol was conducted to study the role of di...

Simultaneous recovery of organic and inorganic content of paper deinking residue through low-temperature microwave-assisted pyrolysis.

Significant amounts of paper deinking residue (DIR) has been and is still being generated from paper deinking processes, representing both an economic and environmental burden for recycled paper mills. Our research on low-temperature (<200 °C) microwave-assisted (MW-assisted) pyrolysis of DIR allows for simultaneously efficient fast separation and recovery of the organic and inorganic content of DIR at relatively low temperature and within 15 min. Our study is the first highly detailed account of the use low-temperature MW-assisted pyrolysis to effect this change. The obtained liquid and solid products were characterized by a variety of analytical techniques (e.g., attenuated total reflection infrared, gas chromatography-mass spectrometry, liquid-state nuclear magnetic resonance (NMR), X-ray diffraction, solid-state cross-polarization/magic-angle spinning (13)C NMR, and Bloch-decay (13)C NMR). The results reveal that the process efficiently separates the inorganic minerals as microwave residue (mainly calcite and kaolinite) from organic matter, and hence the microwave residue could be reused to produce new paper/cardboard products. The organic fraction bio-oil generated is energy-densified and rich in carbohydrates and is a potential source for valuable aromatic compounds.

Determination of the Diffusion Coefficient of Oxygen for a Cover System Including a Pulp and Paper By-Product

Abstract Among the several solutions that have been proposed to curb the problem posed by the generation of acid rock drainage (ARD), the placement of covers with capillary barrier effect (CCBE) has received particular attention. With the creation of a capillary barrier, oxygen has to migrate through a nearly saturated layer, a much slower process than in air. As a consequence, its availability is drastically reduced, reducing ARD generation. An experimental procedure was developed to obtain the diffusion coefficient of oxygen through compacted deinking residues, an organic matter-rich by-product of paper recycling. With the oxygen concentrations obtained as a function of time, it was possible to deduce the diffusion coefficients based on the best reproductions of laboratory results, using the computer code POLLUTE v.6. As expected, it was found that the diffusion coefficient—and the associated flux—is highly influenced by the degree of saturation of the sample. Beyond a threshold in the vicinity of 85%, a one order of magnitude drop in the diffusion coefficient was observed. A comparison of the results obtained with previously published data shows that deinking residues constitute a very effective oxygen barrier material due both to its ability to maintain a high degree of saturation and to rapidly consume oxygen. Given the latter, special care was needed in defining the most appropriate equipment design, sample preparation method, and testing procedure.

Determination of the Soil Water Characteristic Curve of Highly Compressible Materials: Case Study of Pulp and Paper By-Product

Abstract A technique was developed for the determination of various points of the soil-water characteristic curve (SWCC)—including the air entry value (AEV)—of compressible materials from one single test. The testing setup, which employs the axis-translation technique, is presented and the testing methodology, explained. With the proposed methodology, it is possible to determine the volume of the sample at various stages of the desaturation process, thus making it possible to determine the degree of saturation and volumetric water content for each level of suction applied. The results of some tests performed on deinking residues (DR), a fibrous and highly compressible industrial by-product used in geoenvironmental works, are presented and discussed. It is shown that if volume changes that samples undergo during desaturation are not considered, the volumetric water content and degree of saturation of the sample is underestimated at all suction values. One important consequence is that lower hydraulic conductivities are obtained from mathematical models based on the SWCC.

Effect of de-inking paper sludge compost application on soil chemical and biological properties

A 2-yr field study evaluated the effect of applying compost of de-inking paper residues and poultry manure (DSPC) on the chemical and biological properties of Tilly silt loam (Gleyed Humo-Ferric Podzol) in Sainte-Croix de Lotbinière, Qué bec, Canada. The experiment began in 1996 with snap bean ( Phaseolus vulgaris L. ‘Centralia’) and continued in 1997 on the same plots with potato ( Solanum tuberosum L. ‘Gold Rush’). In 1996, treatments included three rates of mineral fertilizer (MF) (60, 120 and 180 kg P2O5-K2O ha-1), three rates of DSPC (14, 28 and 42 Mg ha-1 on a dry matter basis) alone or in combination with MF, and an untreated control. In the spring of 1997, main plots were divided into four subplots and P fertilizer was applied at 0, 44, 88 and 132 kg ha-1. The DSPC increased soil pH and water content. Soil inorganic N increased just after DSPC application, but this effect lasted only 1 yr. Soil Mehlich-3 extractable P showed a significant increase due to DSPC application and the increase was much larger when DSPC was applied in combination with P fertilizer. Soil phosphatase and urease activities were also increased by DSPC. Application of DSPC increased soil Mehlich-3 extractable K and Mg contents. Except for Mn and Zn, soil Mehlich-3 extractable heavy metal contents were not influenced by DSPC. This experiment indicates that compost derived from a mixture of de-inking papermill sludges and poultry manure is a potential source of nutrients for crops and can effectively improve chemical and biological properties of low fertility or degraded soils. Key Words: De-inking sludge, paper biosolids, poultry manure, phosphorus, potassium, enzyme activity

Diffusion of oxygen through a pulp and paper residue barrier: Discussion

The authors have presented an interesting paper on the use of deinking residues to create an oxygen barrier. The paper includes some results from laboratory tests, which can be difficult to perform, and an interpretation based on Fick’s laws solutions. Although the writers, like other researchers active in this field, have expressed some reservations regarding the placement of organic cover materials on reactive (acid producing) tailings (as opposed to inorganic materials such as soils and non-acid generating tailings), it is nevertheless recognized that the proposed approach for controlling the production of acid mine drainage (AMD) is certainly worth investigating. Covers made with deinking residues may eventually be added to the few control methods available for mine operators faced with the prospect of dealing with sulfidic mine and milling wastes. In the following paragraphs, the writers would like to discuss some issues relevant to the problem at hand, including some comments and questions for the authors and interested readers. Air versus equivalent porosity

Diffusion of oxygen through a pulp and paper residue barrier

Acid mine drainage can be curbed or reduced significantly by covering tailings sites with an oxygen barrier. In this study, the ability of pulp and paper residues, more specifically deinking residues, to function as such a barrier was investigated. Field data from two sites show that O2 diffusion through the barriers can be greatly reduced. To better understand how oxygen migrates through deinking residues and to develop prediction tools for future design with deinking residues, one-dimensional effective diffusion coefficients (De) were determined by fitting laboratory experimental curves (O2 concentration versus time data) to curves obtained from computer simulations. The results obtained confirmed the behaviour observed in soil covers: the effective diffusion coefficients are highly dependent on the degree of saturation (Sr) of the compacted material. The De values obtained in this study compare well with those published in the literature for several materials compacted at similar Sr. The De values varied from 8.3 × 10-9 m2/s (Sr approximately 91%) to 9.7 × 10-7 m2/s (Sr approximately 76%). The O2 consumption by biodegradation appears to be an important factor in the reduction of the O2 flux that can reach the bottom of the barrier.Key words: oxygen diffusion, pulp and paper residues, barrier, acid mine drainage.

Use of Paper De-inking Residues in Potato Production

In 1991, a project was initiated in collaboration with the Daishowa paper company to characterize de-inking residues resulting from paper recycling in detail and to determine the value of this organic residue as an amendment to agricultural soils. Our objective was to determine the effects of field applications of de-inking residues on potato crop culture. In 1992, 1993, and 1994, experimental plots were established and maintained at the Horticultural Experimental Farm of Laval Univ. A factorial design was composed of four replications of four doses of de-inking residues (0, 15, 30, and 45 t·ha–1) combined with four doses of N (0, 45, 90, and 135 kg·ha–1). Treatments were applied to a total of 64 plots. The results indicate the importance of adjusting the fertilization to prevent the immobilization of N by the residues. In 1992, as a result of adding de-inking residues, potato yields were increased significantly when sufficient N fertilizer was added. However, significant decreases in yield were noted when a high level of de-inking residues was applied without any adjustment of the C:N ratio. In 1993, potato yields were reduced in treatments having a second application of residue at the highest doses (30 and 45 t·ha–1), even when additional N was provide. Interestingly, harvested tubers gave no indication of toxicity effects due to heavy metals or other contaminants. Results also will be discussed in terms of overall potato quality and the incidence of disease.

Effects of De-inking Sludge on soil Properties and Corn Growth

The large amount of organic carbon content present in de-inking residues makes them attractive for use in agricultural soils as an organic soil amendment. Greenhouse bioessays were undertaken to evaluate the agronomic value of de-inking sludge (DS). It was incorporated in a sandy soil to study the effects of different rates of de-inking residue amendments and N fertilizer combinations on soil properties and growth of corn. Particular attention was given to trace element concentrations. In a split factorial design, three variables were investigated: harvest time (after 20, 40, and 60 days), application rates of DS (0, 35, 70, and 105 t·ha–1), and four N rates (0, 140, 280, and 420 kg·ha–1). Chemical analyses of the fresh residues did not indicate the presence of heavy metals at levels potentially toxic to the environment. Soil chemical properties were clearly improved following the incorporation of DS. For example, adding different amounts of DS had a significant impact on the pH, the cation exchange capacity, and soil moisture. In addition, salinity was not affected with DS application. Seed germination was high in all the treatments and was not significantly influenced by DS application. Moreover, results on vegetative growth indicated a good relationship between the C:N ratio and biomass production. The DS combined with supplemental fertilizer seems to have a positive effect on plant growth. Overall, these results suggest that the limiting factor in de-inking paper sludge valorization is the amount of N available to the plant. Also, no other toxic products were found that could be harmful to the environment.

Mineland Reclamation Using Office Waste Paper De-Inking Residue

Revised 10/03/94; Subaccount No. 543845; This report is the Final Report for Phase III of the Minnesota Office of Environmental Assistance funded project Evaluation of Uses of De-inking Residue. Phase III of this project was previously entitled Mineland Reclamation. Prepared for: Minnesota Office of Environmental Assistance, 1350 Energy Lane, St. Paul, MN 55108