Bleaching optimization at WestRock mill in Covington, Virginia

TAPPI Journal ◽  
2016 ◽  
Vol 15 (9) ◽  
pp. 581-586 ◽  
Author(s):  
RICARDO B. SANTOS ◽  
PETER W. HART ◽  
DOUGLAS C. PRYKE ◽  
JOHN VANDERHEIDE
Keyword(s):  
Hydrogen Peroxide ◽  
Sodium Hydroxide ◽  
Chlorine Dioxide ◽  
Capital Expenditures ◽  
Equipment Repair ◽  
Optimization Program ◽  
Hardwood Pulp ◽  
Improved Performance

The WestRock mill in Covington, VA, USA, initiated a long term diagnostic and optimization program for all three of its bleaching lines. Benchmarking studies were used to help identify optimization opportunities. Capital expenditures for mixing improvement, filtrate changes, equipment repair, other equipment changes, and species changes were outside the scope of this work. This focus of this paper is the B line, producing southern hardwood pulp in a D(EP)DD sequence at 88% GE brightness. The benchmarking study and optimization work identified the following opportunities for improved performance: nonoptimal addition of caustic and hydrogen peroxide to the (EP) stage, carryover of D0 filtrate to the (EP) stage, and carryover of (EP) filtrate to the D1 stage. As a result of actions the mill undertook to address these opportunities, D0 kappa factor decreased about 5%, sodium hydroxide consumption in the (EP) stage decreased about 35%, chlorine dioxide consumption in the D1 stage decreased about 25%, and overall bleaching cost decreased about 15%.

scholarly journals Engineering Sr-doping for enabling long-term stable FAPb1−xSrxI3 quantum dots with 100% photoluminescence quantum yield

2021 ◽  
Vol 9 (5) ◽  
pp. 1555-1566
Author(s):  
Andrés F. Gualdrón-Reyes ◽  
David F. Macias-Pinilla ◽  
Sofia Masi ◽  
Carlos Echeverría-Arrondo ◽  
Said Agouram ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Toxic Metals ◽  
Environmentally Friendly ◽  
Photoluminescence Quantum Yield ◽  
Improved Performance ◽  
Pb Substitution

The Pb substitution in quantum dots (PQDs) with lesser toxic metals has been widely searched to be environmentally friendly, and be of comparable or improved performance compared to the lead-perovskite.

Production of monosaccharides from poplar by a two-step hydrogen peroxide-acetic acid and sodium hydroxide pretreatment

2021 ◽  
Vol 170 ◽  
pp. 113820
Author(s):  
Hong Liao ◽  
Jiaxin You ◽  
Peiyao Wen ◽  
Wenjun Ying ◽  
Qianqian Yang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Sodium Hydroxide

Enhanced Long-Term Color Stability of Teeth Treated with Hydrogen Peroxide and Non-Thermal Atmospheric Pressure Plasma Jets

2014 ◽  
Vol 11 (11) ◽  
pp. 1010-1017 ◽  
Author(s):  
Seoul Hee Nam ◽  
Hyun Wook Lee ◽  
Jin Woo Hong ◽  
Hae June Lee ◽  
Gyoo Cheon Kim
Keyword(s):  
Hydrogen Peroxide ◽  
Atmospheric Pressure ◽  
Atmospheric Pressure Plasma ◽  
Color Stability ◽  
Plasma Jets ◽  
Pressure Plasma

Long-term oral n-acetylcysteine reduces exhaled hydrogen peroxide in stable COPD

2005 ◽  
Vol 18 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Fernando De Benedetto ◽  
Antonio Aceto ◽  
Beatrice Dragani ◽  
Antonella Spacone ◽  
Stefano Formisano ◽  
...  
Keyword(s):  
Hydrogen Peroxide

The value relevance of capital expenditures and the business cycle

2018 ◽  
Vol 35 (3) ◽  
pp. 386-406 ◽  
Author(s):  
Sungsoo Kim ◽  
Brandon byunghwan Lee
Keyword(s):  
Business Cycles ◽  
Stock Returns ◽  
Value Relevance ◽  
Financial Data ◽  
Capital Expenditures ◽  
Capital Investments ◽  
Content Type ◽  
Market Participants ◽  
Business Conditions

Purpose This paper aims to clarify the relationship between corporate capital investments and business cycles. Specifically, a major purpose of this paper is to investigate whether there are inherent differences in corporate investment patterns and whether the stock market exhibits different reactions to the value relevance of capital expenditures across different business conditions. Design/methodology/approach The authors use pooled ordinary least square regressions with archival stock price data and financial data from CRSP and Compustat. The authors regress buy and hold returns on the main test variables and control variables that are identified to be related to the investment literature. Findings This paper provides empirical evidence that US firms’ capital expenditures are more value relevant to capital market participants during expansionary business cycles and, conversely, less value relevant during contractionary business cycles. This evidence validates previous literature that has found the information content of capital expenditures to be uncertain and cyclical in nature. Research limitations/implications The main limitation of this paper, as with other work dealing with stock returns and archived financial data, is that the authors try to match stock returns with contemporaneous financial data in an association study context. The precise mapping in this methodology is always challenging and has been questioned in the literature. Practical implications This paper has various implications for capital market participants. Capital expenditures are good news for investors, but they will make a better investment when firms make capital investments during an expansionary period. Creditors deciding whether to extend credit to firms would benefit from more accurate information on the viability of long-term investment. The results also suggest to creditors that an excessive number of loans during the contractionary period may be suboptimal because firms’ returns on capital investment are smaller in that period than in the expansionary period. Social implications Given the valuation of implications of long-term capital investments across different business conditions, this paper sheds light on asset allocations for mutual funds, institutional investors who are entrusted with investors’ investments including retirement funds. Originality/value This paper fulfils an identified need to study how capital investments are valued differently across different business conditions.

scholarly journals Hydrogen peroxide and chlorine dioxide against parasite Ichthyophthirius multifiliis (Protozoa, Ciliophora) in jundiá fingerlings

2017 ◽  
Vol 47 (12) ◽  
Author(s):  
Natalia da Costa Marchiori ◽  
Fabiano Muller Silva ◽  
Maurício Laterça Martins ◽  
Hilton Amaral Junior ◽  
Bruno Corrêa da Silva
Keyword(s):  
Hydrogen Peroxide ◽  
Chlorine Dioxide ◽  
Fish Farming ◽  
Control Group ◽  
Chemical Agent ◽  
Ichthyophthirius Multifiliis ◽  
Larval Phase ◽  
Group Data ◽  
Active Chemical ◽  
Continuous Bath

ABSTRACT: Ichthyophthiriasis is a worldwide fish disease with great financial impact on freshwater fish farming due to its associated high mortality rates. Current study assesses the parasiticidal capacity of hydrogen peroxide (H2O2) and chlorine dioxide (ClO2) against the causative agent, Ichthyophthirius multifiliis, in jundiá. Median lethal concentration (LC50, 96h) of each chemical agent was established, as well as the minimum inhibitory concentration of hydrogen peroxide for the parasite´s infectious larval phase (theront). Products were tested asynchronously in parasitized fingerlings for short and long baths at the following concentrations and exposure times: 1. Hydrogen peroxide: (T1) continuous bath - 30ppm and (T2) 50ppm; (T3) short bath - 150ppm, during 1h and (T4) 250ppm during 1h; control group (without any chemical agent). 2. Chlorine dioxide: (T1) continuous bath - 4ppm and (T2) 20ppm; (T3) short bath - 200ppm, during 1min; (T4) short bath - 400ppm, during 1min and control group. Data analysis demonstrated a concentration of 82.54ppm of the commercial product (or 24.76ppm of the active chemical agent) as LC50, 96h of H2O2 and 38.4ppm product (or 2.68ppm of the active chemical agent) for ClO2. Hydrogen peroxide concentration causing 100% mortality rate of theronts in 1h was 25ppm (product, or 7.5ppm of the active chemical agent). At the end of the fourth day of curative experiment, 98% of the animals died by ichthyophthiriasis. No treatment was effective against the parasite.

scholarly journals A Comparative Survey Of Capital Investment Decision Practices In The United States And The United Kingdom

2011 ◽  
Vol 1 (11) ◽  
Author(s):  
Thomas Klammer ◽  
Neil Wilner ◽  
Jan Smolarski
Keyword(s):  
United States ◽  
Risk Management ◽  
United Kingdom ◽  
The United States ◽  
Capital Expenditures ◽  
The United Kingdom ◽  
Management Techniques ◽  
Comparative Survey ◽  
The Uk

Capital expenditures can be crucial to firms long-term success, especially in a complex global environment. As companies increasingly compete in the global market place, it is important to study project evaluation processes from an international perspective. Capital investments involve substantial monetary commitments and risks that affect long-term firm profitability and influence capital allocation decisions in the future. Survey research in the area of capital expenditure analysis has been extensively done in both the United States [US] and the United Kingdom [UK]. This research is the first comparative survey of practices in both countries that we are aware of. A direct comparison of the use of project evaluation, management science, and risk management techniques in the two countries is made. The survey instrument used is an adaptation of the Klammer [1970] instrument that has been used repeatedly in surveys of American firms. This is the first time that it has been applied to British firms. The use of a common instrument allows for more meaningful comparisons. The samples consisted of 127 American and 59 British firms with sales of at least $100 million and capital expenditures of at least $10 million. Preliminary results indicate a continued extensive use of discounted cash flow techniques by US firms. Techniques such as payback or urgency continue to be used, but to a lesser degree than discounting. Firms in the UK also make extensive use of discounting but do so to a lesser degree than their American counterparts. Payback is widely used in the UK. Risk management techniques are widely used in both countries, with sensitivity analysis being the most popular technique in both countries. Extensive use of technical and administrative procedures, such as detailed budgets, standardized forms and post-audits, are evidenced in both countries. The paper offers reasons that have to do with organizational structure and form, as well as market differences, to explain our results.

Initiating ECF bleaching sequences of eucalyptus kraft pulps with Z/D and Z/E stages

Holzforschung ◽  
2010 ◽  
Vol 64 (1) ◽  
Author(s):  
Juan C. García ◽  
Francisco López ◽  
Antonio Pérez ◽  
M. Angels Pèlach ◽  
Pere Mutjé ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Chlorine Dioxide ◽  
Ecological Impact ◽  
Substantial Reduction ◽  
Reference Sequence ◽  
Kraft Pulps ◽  
Eucalyptus Kraft Pulp ◽  
The Impact ◽  
Ecf Bleaching ◽  
Ozone Bleaching

Abstract Ozone bleaching is a common practice in pulping, and also of eucalyptus, where it is usually applied in combination with bleaching sequences based on oxygen, hydrogen peroxide, or chlorine dioxide. Ozone has been proven to be a highly efficient and competitive bleaching chemical in terms of delignification efficiency, low costs, and reducing ecological impact. The objective of the present work was to evaluate technology with ozone/alkaline extraction (Z/E) and ozone/chlorine dioxide (Z/D) for bleaching of eucalyptus kraft pulp. Primarily, the impact of these bleaching steps on refinability and quality of pulp should be investigated. As reference, the sequence D*(EP)D (hot chlorine dioxide, extraction in presence of hydrogen peroxide, chlorine dioxide) was selected, which is considered as the state-of-the-art bleaching in elemental chlorine free (ECF) bleaching technology. Various bleaching sequences with ozone in their first step (Z/D(EP)DP, Z/D(EP)DD, Z/EDP, Z/EDD and A*Z/EDP) were found to provide kraft pulps of similar brightness and in similar yield as the reference sequence D*(EP)D. The kappa number, viscosity, and the contents of glucose and xylose, and hexenuronic acid of the pulps were also similar. In addition, the Z sequences resulted in a substantial reduction of the total chlorine dioxide consumption (more than 30.3% in all cases). The A*Z/EDP sequence, which proved to be the most efficient, yielded 87.5% ClO2 reduction. The studied bleaching sequences also resulted in substantially improved brightness reversal with regard to the reference sequence. The sequence A*Z/EDP was also the most efficient as regards the removal or organochlorines (OX) from the pulp and their reduction in the effluents (AOX). Ozone bleaching sequences improved paper strength, especially with the A*Z/EDP sequence.

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