Burned wood in the pulp and paper industry: A literature review

2004 ◽  
Vol 80 (4) ◽  
pp. 473-477 ◽  
Author(s):  
Paul Watson ◽  
Simon Potter

Fires play an integral part in Canadian forest architecture. Low-value wood, from burned stems, is an important source of fibre for the pulp and paper industry. Although wood chemistry changes induced by fire are substantial, burned stems exhibit a demarcation layer between the char and undamaged wood which is only a few cells thick. The loss of stem moisture content requires that burned wood is processed within one year. Aggressive debarking will minimize charcoal contamination and careful metering of chips from burned wood into any pulping process is essential. Chips with low moisture content must be pre-steamed prior to kraft cooking, and chemical pre-treatment may improve mechanical pulp quality. Key words: burn intensity, wood chemistry, charring, stem moisture content, charcoal contamination, chip metering

2021 ◽  
Vol 18 (2) ◽  
pp. 204-215
Author(s):  
I. L. Chulkova ◽  
I. A. Selivanov

Introduction. The need for a more efficient and varied use of waste from the pulp and paper industry dictates the need to search for new directions for the use of such waste in construction materials science technologies.Materials and methods. In the studies the fibre waste of the Perm Cardboard LLC company with a moisture content after washing of 300% by weight was used. Currently, many issues of theory and practice the production of materials from the fibre waste are not entirely solved, resulting in a number of provisions borrowed from the theory of the production of concrete mineral aggregates, as well as the production of pulp and paper industry.Results. Due to its chemical and material composition, the possibility of using the fibre waste in construction materials science technologies as an independent air binder is shown. The studies have established that the initial moisture content of the fibre waste as a binder affects the final quality indicators of a dry material. Thus, the lowest dry material density of 350 kg/m3 is observed at the initial humidity of the mixture in the range of 650% by weight. At a density of 350 kg/m3, the hygroscopicity of the material is 4.3%, the shrinkage from 10 to 25%. The drying time of the product is within 11 hours. A leveling high shrinkage is achieved by introducing light aggregates with a rough surface during the molding process.Discussion and conclusions. The obtained data on the structure, the composition of the fibre waste, as well as the dependence and regularities of the behavior of a highly concentrated dispersed system of the ‘fibre waste-water’ type show the possibility of using the fibre waste for the production of thermal insulation materials, both as a main component and in a composition with aggregates as an independent air binder. At the same time, the final density indicators of thermal insulation products are within the limits established by regulatory documents.


2004 ◽  
Vol 50 (3) ◽  
pp. 217-227 ◽  
Author(s):  
J. Nuortila-Jokinen ◽  
M. Mänttäri ◽  
T. Huuhilo ◽  
M. Kallioinen ◽  
M. Nyström

In this study, membrane filtration as an internal purification method, “the kidney7rdquo;, in the pulp and paper industry is discussed. Membrane filtration is economically competitive and a very versatile process. It can be used to remove the enriched organic and/or inorganic loads either partially or totally from, for example, the mechanical pulping and paper making water circuits and it can be applied to various points within the process. With the so-called shear enhanced membrane modules very high fluxes, in ultrafiltration about 400 L/(m2h) and in nanofiltration fluxes almost 200 L/(m2h), have been obtained. Depending on the membrane, suspended solids (microfiltration), polysaccharides, extractives and high molar mass lignous substances (ultrafiltration) and multivalent salts (nanofiltration) can be removed. Ultrafiltration permeate can well be used in paper machine showers to replace fresh water. The quality of the nanofiltration permeate is significantly higher than that of ultrafiltration. The membrane processes can be enhanced by various pre-treatment techniques to produce higher permeate fluxes and to eliminate membrane fouling. Such pre-treatment methods are, e.g., chemical treatment, ozonation and biological treatment. The most cost-effective processes were chemical flocculation, pH adjustment and thermophilic aerobic biological treatment.


1994 ◽  
Vol 29 (5-6) ◽  
pp. 219-228 ◽  
Author(s):  
D. Berge ◽  
H. Ratnaweera ◽  
H. Efraimsen

AOX removal from pulp and paper industry wastewater with traditional methods is still very difficult. A novel application, irradiation by high energy electron beam (EB), is investigated and 40% and 70% AOX removals were obtained by 10 kGy and 50 kGy dosages, respectively. Further removals are possible at higher dosages. Chemical pre-treatment had no significant effect on overall AOX removal by EB-treatment, while biological post-treatment removed AOX further. Practical applications at large pulp and paper plants are considered, and further research on the application of EB-treatment on concentrated effluents or sludges is recommended.


2004 ◽  
Vol 50 (3) ◽  
pp. 229-238 ◽  
Author(s):  
M. Mänttäri ◽  
M. Nyström

Ultra- and nanofiltration with high shear CR-filters have been utilized for cleaning of clear filtrates and effluents from the pulp and paper industry. The aim was to find out how different nanofiltration membranes operate at high shear conditions. The filtration efficiency of the membranes was evaluated by measuring flux, retention and fouling at various recovery and pH conditions. High fluxes (∼100 L/(m2h)) for nanofiltration membranes were measured when circulation waters from the paper machine were filtered at neutral conditions. In the filtration of discharge of external activated sludge treatment plants we measured fluxes around 150 L/(m2h) even at a concentration factor of 12. The best NF membranes removed over 80% of the organic carbon and of the conductivity and almost completely eliminated the color. With acidic waters fluxes and retentions were significantly lower. The NF270 membrane from Dow and the Desal-5 membranes from Osmonics had the highest flux and retention properties. However, the Desal-5 membrane lost its retention properties slowly, which restricts its use in the high shear CR-filter. CR-nanofiltration can be used in the pulp and paper industry without feed pre-treatment by ultrafiltration. This increases the attractiveness of high shear CR-nanofiltration.


TAPPI Journal ◽  
2014 ◽  
Vol 13 (6) ◽  
pp. 19-24
Author(s):  
TROY RUNGE ◽  
CHUNHUI ZHANG

Agricultural residues and energy crops are promising resources that can be utilized in the pulp and paper industry. This study examines the potential of co-cooking nonwood materials with hardwoods as means to incorporate nonwood material into a paper furnish. Specifically, miscanthus, switchgrass, and corn stover were substituted for poplar hardwood chips in the amounts of 10 wt %, 20 wt %, and 30 wt %, and the blends were subjected to kraft pulping experiments. The pulps were then bleached with an OD(EP)D sequence and then refined and formed into handsheets to characterize their physical properties. Surprisingly, all three co-cooked pulps showed improved strength properties (up to 35%). Sugar measurement of the pulps by high-performance liquid chromatography suggested that the strength increase correlated with enriched xylan content.


1999 ◽  
Vol 53 (10) ◽  
pp. 1334-1338 ◽  
Author(s):  
Yoshiya Kuide ◽  
Kazuyoshi Yamamoto

Sign in / Sign up

Export Citation Format

Share Document