Researchers have linked resin and fatty acids (RFAs) to acute toxicity, especially in thermomechanical and chemithermomechanical pulp and paper mill effluents. Thus, the measurement of total RFAs may be a rapid, inexpensive alternative to standard methods of toxicity monitoring, such as 96-hour rainbow trout testing. Current procedures for the analysis of RFAs typically involve solvent extraction and concentration, derivatization, and analysis by GC, HPLC, or TLC. These procedures are far too expensive, complicated, and time-consuming for implementation at mill sites. / This thesis reports the development of a rapid, colourimetric assay based on the dye methylene blue (MB) for the quantification of resin and fatty acids in pulp and paper mill effluents. This MB assay uses the complexation of the cationic organic dye molecule to the carboxylic acid groups of RFAs to form a measurable chromophore. The electrically neutral, blue-coloured complexes are then extracted into a poorly polar organic solvent, dichloromethane. The measured absorbance at 655 nm is directly related to the total RFA concentration in the effluent sample. / The methylene blue assay is inexpensive and simple to use. It has a method detection limit of 0.589 mg/L total RFA. There are good correlations between the results obtained using the methylene blue assay and a well-established GC assay, and between RFA concentrations measured by the MB assay and acute toxicity measured by Microtox. The assay is sufficiently simple and rapid to be practical for routine in-mill monitoring.

Column flotation as a concept was introduced approximately 90 years ago at Inspiration Copper Co., Arizona, with the first successful installation occurring at Les Mines Gaspe, Quebec, in 1981. Column flotation has since been applied to many other industries including deinking of recycled paper. / The research is a comparison of industrial bubble generating devices in a pilot and laboratory column using water/Dowfroth and pulp sampled on-line from a local deinking plant. The pilot column tested combinations of 6, 4 and 2 stainless steel (ss) porous spargers, and filter cloth and jetting sparger; the lab column used a single ss porous sparger. Long term tests on the pilot column were also done to evaluate maintenance issues. / Trends from the water/Dowfroth tests were used to predict results using pulp. Six ss spargers outperformed the other spargers in all cases. The performance of the lab column sparger matched 4 spargers, with the filter cloth performing marginally better than the jetting sparger or 2 spargers. / Gas holdup (Eg) and bubble surface area flux (Sb) gave good correlation with ink removal with all spargers failing within a narrow range. Surface area flux is suggested over Eg unless bubble diameter or superficial gas velocity are indeterminable. Sb > 100 s-1 gave ink removals equal to the plant Voith cells. An Sb below 40 s-1 gave zero ink removal. The lab and pilot column followed slightly different trends which was attributed to column diameter (i.e., wall effects). / The ss and filter cloth spargers present long term maintenance issues due to plugging. The performance of the 6 ss spargers decreased more quickly than any other during the long term tests, attributed to lower air velocities per pore.

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Trees of Slash pine showed reduced growth, by an order of magnitude, following exposure to two hurricanes (Elena and Kate) in 1985. The reduced growth is caused by salt spray chlorosis and/or defoliation from high winds. Ring width, radial tracheid diameter, radial cell number, tracheid length and microfibril angle were measured for samples from before and after major storms. Data for ring width, earlywood radial cell diameter and cell number were not normally distributed, while data for latewood radial cell diameter, tracheid length and microfibril angle showed normal distributions. There were significant statistical differences for all main effects for ring width, earlywood radial cell diameter, cell number and tracheid length. The data for latewood radial cell diameter show significant differences for effects of time and height, but not for compass direction. There are significant differences in earlywood cellulose microfibril angle for height effects, and no difference for time and direction effects. Data for latewood cellulose microfibril angle show significant differences for the effects of time and height. / Source: Dissertation Abstracts International, Volume: 55-01, Section: B, page: 0016. / Major Professor: Loran C. Anderson. / Thesis (Ph.D.)--The Florida State University, 1993.

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In the past two decades, China has achieved a spectacular success in its economic growth. As a basic input for the production process, the forest resource has been one of the fundamental factors propping up the expansion of China's economy. When China is absorbing imports of timber products in the global market, studies of China's forestry system and its timber market incite greater interest. This paper represents a systematic approach to probe into the comprehensive realities of China's forestry system and its timber market. Econometric methods are applied in analyzing the demand and supply patterns. The empirical analysis is used to forecast the quantity demanded for timber products in China.

Pentachlorophenol (PCP) is a biocide which is widely used for its toxicity to microorganisms. Its major application is in wood preservation, and PCP at abandoned wood preserving sites is a major source of environmental pollution. Although much of the literature documents aerobic treatment for PCP, research indicates that there is great potential for anaerobic dechlorination of these compounds. The objectives of this investigation were to study the acidogenesis phase of the anaerobic biodegradation process; how acidogenesis is affected by PCP toxicity alone and in the presence of zinc; what role acidogenesis plays in the biodegradation of PCP; and how operating parameters, such as organic loading rate (OLR) and solids retention time (SRT) affect the degradation of PCP during acidogenesis. Batch anaerobic toxicity assays (ATAs) were performed to quantify the toxicity threshold for PCP and zinc, and to study the effect of these toxicants on volatile acids production. Continuous reactors (chemostats) were operated at SRTs of 0.25-0.61 day to kinetically exclude methanogenesis from acetate, so that the effects of the toxicants on acidogenesis could be evaluated PCP was found to have a toxicity threshold of 2.7-3.0 mg/L and zinc 23-27 mg/L in batch systems. Acetate utilizers showed the first signs of inhibition in PCP spiked systems, whereas hydrogen utilizers were the first organisms affected in response to a zinc spike. In the continuous systems, PCP in spike concentrations of 7.0 mg/L did not affect the quantity or composition of volatile acids produced in the chemostats. A rise in headspace hydrogen at 30 mg/L zinc indicated that hydrogen utilizers became inhibited in the presence of high zinc concentrations PCP was degraded, with approximately half of the degradation occurring during acidogenesis. GC/MS analysis detected no intermediate chlorophenols in the effluent. The efficiency of degradation varied indirectly with spike concentration and directly with SRT / acase@tulane.edu