scholarly journals Control of the Accumulation of Non-Process Elements in Pulp Mills with Bleach Filtrate Reuse: A Chemical Equilibrium Approach to Predicting the Partitioning of Metals in Pulp Mill and Bleach Plant Streams

2000 ◽  
Author(s):  
W.J. Jr. Frederick ◽  
A.W. Rudie ◽  
G.W. Schmidl ◽  
S.A. Sinquefield ◽  
G.L. Rorrer ◽  
...  
Keyword(s):  
Chemical Equilibrium ◽  
Pulp Mill ◽  
Pulp Mills ◽  
Equilibrium Approach ◽  
Process Elements

Fate of phosphorus in the recovery cycle of the kraft pulping process

TAPPI Journal ◽  
2020 ◽  
Vol 19 (3) ◽  
pp. 139-148
Author(s):  
MARYAM SADEGH MOUSAVI ◽  
NIKOLAI DEMARTINI
Keyword(s):  
Kraft Pulp ◽  
Pulp Mill ◽  
Field Studies ◽  
Kraft Pulping ◽  
Pulp Mills ◽  
Recovery Cycle ◽  
Green Liquor ◽  
Green Liquor Dregs ◽  
Kraft Pulp Mills ◽  
Negative Effect

The accumulation of nonprocess elements in the recovery cycle is a common problem for kraft pulp mills trying to reduce their water closure or to utilize biofuels in their lime kiln. Nonprocess elements such as magne-sium (Mg), manganese (Mn), silicon (Si), aluminum (Al), and phosphorus (P) enter the recovery cycle via wood, make-up chemicals, lime rock, biofuels, and process water. The main purge point for these elements is green liquor dregs and lime mud. If not purged, these elements can cause operational problems for the mill. Phosphorus reacts with calcium oxide (CaO) in the lime during slaking; as a result, part of the lime is unavailable for slaking reactions. The first part of this project, through laboratory work, identified rhenanite (NaCa(PO4)) as the form of P in the lime cycle and showed the negative effect of P on the availability of the lime. The second part of this project involved field studies and performing a mass balance for P at a Canadian kraft pulp mill.

Pulp mill process closure: a review of global technology developments and mill experiences in the 1990s

2004 ◽  
Vol 50 (3) ◽  
pp. 183-194 ◽  
Author(s):  
S.C. Stratton ◽  
P.L. Gleadow ◽  
A.P. Johnson
Keyword(s):  
Manufacturing Industry ◽  
Pollution Prevention ◽  
Optimal Solution ◽  
Pulp Mill ◽  
Thermomechanical Pulp ◽  
Pulp Mills ◽  
Oxygen Delignification ◽  
Manufacturing Operations ◽  
The Impact ◽  
Mill Process

The impact of effluent discharges continues to be an important issue for the pulp manufacturing industry. Considerable progress has been made in pollution prevention to minimize waste generation, so-called manufacturing “process closure.” Since the mid-1980s many important technologies have been developed and implemented, many of these in response to organochlorine concerns. Zero effluent operation is now a reality for a few bleached chemi-thermomechanical pulp (BCTMP) pulp mills. In kraft pulp manufacturing, important developments include widespread adoption of new cooking techniques, oxygen delignification, closed screening, improved process control, new bleaching methods, and systems that minimize pulping liquor losses. Coupled to this is a commitment to reduce water use and maximize reuse of in-mill process streams. Some companies pursued bleach plant closure, and many have been successful in eliminating a portion of their bleaching wastewaters. However, the difficulties inherent in closing bleach plants are considerable. For many mills the optimal solution has been found to be a high degree of closure coupled with external biological treatment of the remaining process effluent. No bleach plants at papergrade bleached kraft mills are known to be operating effluent-free on a continuous basis. This paper reviews the important worldwide technological developments and mill experiences in the 1990s that were focused on minimizing environmental impacts of pulp manufacturing operations.

Purification of pulp mill condensates by an adsorptive process on activated carbon

Holzforschung ◽  
2019 ◽  
Vol 73 (6) ◽  
pp. 589-597 ◽  
Author(s):  
José A.F. Gamelas ◽  
Sofia M. Rebola ◽  
Margarita G. Evtyugina ◽  
Valdemar I. Esteves ◽  
Dmitry V. Evtuguin
Keyword(s):  
Activated Carbon ◽  
Volatile Compounds ◽  
Water Cycle ◽  
Black Liquor ◽  
Pulp Mill ◽  
Dimethyl Disulfide ◽  
Pulp Mills ◽  
Wide Range ◽  
New Process ◽  
Pseudo Second Order

Abstract In order to close the water cycle in pulp mills with condensates instead of fresh water, the malodorous/hazardous volatile compounds and colored substances have to be removed by appropriate efficient methods. In the present work, the condensate from the evaporation of black liquor (BL) from a kraft mill was purified by a batch adsorptive process by means of commercial activated carbon (AC). The effluent was found to contain a wide range of aromatic and organosulfur volatile compounds, including toluene, ethylguaicol, syringaldehyde, dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), 2,3-dimethylthiophene, benzothiol and benzothiophene derivatives. Methanol was the major volatile organic component in the condensate (201 mg l−1), which was, however, poorly adsorbed on the AC surface. Aromatics and organosulfur contaminants were adsorbed almost completely in 2–5 min at 23°C under the optimized AC load (900 mg l−1). The treatment allowed the elimination of up to 99% of the obnoxious odor, color and turbidity of the condensate. The adsorption equilibrium followed the Langmuir model and the pseudo-second-order kinetics. The new process could be incorporated in the pulp mill with relatively low additional reagent costs.

scholarly journals Method for analysis of ClO2 and Cl2 air emissions from pulp mill

2019 ◽  
Vol 34 (1) ◽  
pp. 19-27
Author(s):  
Kimona Häggström ◽  
Magnus Gunnarsson ◽  
Katarina Bremert-Jirholm ◽  
Nina Simic
Keyword(s):  
Chlorine Dioxide ◽  
Analytical Method ◽  
Kraft Pulp ◽  
Pulp Mill ◽  
Air Emissions ◽  
Pulp Mills ◽  
Limit Of Quantification ◽  
Regulatory Standards ◽  
Low Concentrations ◽  
Kraft Pulp Mills

Abstract Chlorine dioxide is commonly used as a bleaching agent in kraft pulp mills. Scrubbers are required to remove any remaining ClO2 from the plant tail gases. To control the air emissions of chlorine compounds, chlorine dioxide and chlorine contents must be monitored to ensure that the strict regulatory standards are met. However, the currently used analytical method is not suitable for detection of low concentrations of chlorine and chlorine dioxide. A new method for measuring chlorine dioxide and chlorine emissions was developed, which ensures compliance with the stringent requirements imposed by the authorities. The two species could be measured separately with a limit of quantification of 3 ppm. The method was robust and easy to use in the pulp mill environment and it was validated both in the laboratory and the field. The specificity of the method was demonstrated, Cl2 analysis was not sensitive to the presence of ClO2 and vice versa. The uncertainty (±2×RSD) of the analytical method in the field was estimated from duplicate measurements performed in the range of 3–500 ppm for ClO2 and 3–300 ppm for Cl2, and was found to be ±20 % and ±10 %, respectively. Possible interferences in the analytical method are also discussed.

Differential recovery of δ13C in multiple tissues of white sucker across age classes after the closure of a pulp mill

2014 ◽  
Vol 71 (5) ◽  
pp. 747-755 ◽  
Author(s):  
T.J. Arciszewski ◽  
A.J. Farwell ◽  
M.R. Servos ◽  
T.D. Jardine ◽  
K.R. Munkittrick
Keyword(s):  
Muscle Tissue ◽  
Pulp Mill ◽  
Pulp And Paper ◽  
White Sucker ◽  
Pulp Mills ◽  
Age Classes ◽  
Pulp And Paper Mills ◽  
Paper Mills ◽  
Gonad Tissue ◽  
Age Range

Techniques to document recovery after the closure of pulp mills that discharge enriching effluents are not well established, but δ13C may be a useful tool. In the 1990s, the muscle tissue of white sucker (Catostomus commersonii) collected downstream of two pulp and paper mills discharging into separate streams (Mattagami and Kapuskasing rivers) was enriched in 13C compared with upstream fish, suggesting uptake of pulp-derived C. The Mattagami River mill was closed in 2006, and analysis of muscle and gonad for δ13C was performed in 2011. As expected, fish captured in 2011 downstream of the operational Kapuskasing mill still showed the influence of the pulp-derived C in muscle and gonad tissue. After the closure of the Mattagami River mill, muscle tissue of white sucker was still enriched in 13C compared with upstream fish, while gonad tissue was not. The patterns observed in the Mattagami River were, however, related to age; the oldest fish showed enrichment of δ13C in both muscle and gonad tissue, suggesting the residual occurrence of pulp-derived C. This study suggests that measurements of stable isotopes in fish across a broad age range may indicate ecosystem improvements. These techniques may also be useful where no data prior to the upgrade or closure are available for comparison.

Some Toxic Constituents of Chlorination-Stage Effluents from Bleached Kraft Pulp Mills

1981 ◽  
Vol 38 (7) ◽  
pp. 739-743 ◽  
Author(s):  
A. B. McKague
Keyword(s):  
Gas Chromatography ◽  
Rainbow Trout ◽  
Kraft Pulp ◽  
Pulp Mill ◽  
Salmo Gairdneri ◽  
Pulp Mills ◽  
Juvenile Rainbow Trout ◽  
Bleached Kraft Pulp ◽  
Toxic Materials ◽  
Kraft Pulp Mills

Constituents responsible for the toxicity of a sample of bleached kraft chlorination-stage effluent to juvenile rainbow trout (Salmo gairdneri) were investigated. Tetrachlorocatechol, 3,4,5-trichlorocatechol, and 2,6-dichlorohydroquinone were identified and evidence was obtained for the presence of other chlorodihydroxybenzenes in toxic acidic fractions of the sample. Concentrations of 0.46 mg/L 3,4,5-trichloro- and 0.74 mg/L tetrachloro-catechol were estimated in the sample by analytical gas chromatography. Toxic materials in the nonacidic fraction were not identified although the nontoxic dichloromethyl methyl sulfone was isolated.Key words: chlorination-stage effluent, toxicity, pulp mill, chlorocatechols, chlorodihydroxybenzenes

scholarly journals Reuse of Residual Biomass of Cellulose Industry for Second Generation Bioethanol Production

2016 ◽  
Vol 6 (1) ◽  
pp. 768-772
Author(s):  
Nei Pereira Junior ◽  
Anelize de Oliveira Moraes ◽  
Luiz Felipe Modesto ◽  
Ninoska Isabel Bojorge Ramirez
Keyword(s):  
Ethanol Production ◽  
First Generation ◽  
Pulp Mill ◽  
Pulp Mills ◽  
Residual Biomass ◽  
Commercial Strain ◽  
Second Generation Bioethanol ◽  
Ssf Process ◽  
Range Of Values ◽  
Simultaneous Saccharification

This study aimed at evaluating the potential of pulp mill residue (PMR) as a feedstock for ethanol production. The simultaneous saccharification and fermentation (SSF) process was operated using 8 gL -1 of a commercial strain of Saccharomyces cerevisiae JP1 under optimal proportions of cellulase cocktail (24.8 FPU/g cellulose of Cellic® CTec2) and cellulosic residue (200 gL -1 ). After 48 hours of pre-hydrolysis at 50ºC and 200 rpm, the fermentation was carried out at 37 ºC, generating 48.5 gL -1 of ethanol in 10 hours and reaching a conversion efficiency of 53.3% from cellulose to ethanol and a volumetric productivity of 4.8 gL -1 h -1 that is within the range of values of first generation ethanol production (5-8 gL -1 h -1 ). These results showed that the pulp mill residue is an interesting and effective feedstock for the production of ethanol, which can be used for fuel purposes in the own pulp mills.  

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