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The production of pulp for paper manufacture, either from virgin wood or recycled paper, generates large amounts of solid waste. This chapter presents an overview of the use of papermill sludges as soil conditioners and amendments for agricultural, horticultural, and sylvicultural applications. In addition, pertinent research is examined in order to understand the advantages and disadvantages associated with paper sludges as alternative sources of organic matter. To evaluate objectively the potential for papermill sludge use as soil conditioners, the chapter examines the origin, composition, qualities, and characteristics associated with the various sludges arising from paper production, processing, and recycling. Characteristics that should be considered and examined before application as soil conditioners include the physical properties, pH, heavy metal and organic compound concentration, organic carbon fractions (carbon-nitrogen ratio), decomposition patterns and rates, plant nutrient availability (especially nitrogen concentration), salinity, and sodicity.

The evaluation of the optical properties of papers and composites made from nanocellulose revealed that it is possible to obtain translucent to highly optically transparent materials from nanocellulose, comparable to the optical transparency of some thermoplastic and thermoset polymers as well as glass. For the fabrication of optically transparent nanocellulose papers, the terminology nanofibrillated cellulose (NFC) might be more appropriate because very high level of transparency can be reached for cellulose fibre (CNF) having a diameter typically below 15 nm. The chapter describes the fabrication methods reported to fabricate optically transparent nanocellulose composites and the detailed research carried out using either NFC or bacterial cellulose (BC) to design this relatively new class of polymeric composite materials. BC was mostly used as a model material to fabricate the first optically transparent nanocomposites, probably because no energy-intensive process is needed to obtain very fine CNF.

This chapter explains the solubility of gas in water confined to a small pore is estimated by two different methods. The first is an analytical method where simple but reasonable approximations are used to show that in very small pores CH4 solubility should be somewhat larger than the macroscopic measurement values. The second solubility estimate for methane in a small pore is made using equilibrium molecular dynamics simulations. Molecular simulations have made enormous strides in recent years and are gradually becoming a ubiquitous tool in science and engineering. This is due to the development of new methods for description of complex fluids and materials and due to the availability of high-speed and large-capacity computers to an increasing number of researchers. The chapter discusses the solubility of methane in bulk water and in water confined to micropore using the test-particle method combined with the excluded volume map sampling method.

This chapter shows that secondary metabolites have been valuable, occasionally even indispensable, in classifications that are expected to be unequivocal and stable. Gross separations were originally introduced using paper chromatography or chemical paper tests, but these have not been used recently in chemotaxonomy except in a few simple diagnostic tests. Gas chromatography (GC) has mostly been used for volatile chemical compounds. High-performance liquid chromatography (HPLC) has become the method of choice for most nonvolatile secondary metabolites. HPLC using gradient elution on reversed-phase material allows a good separation of a large range of secondary metabolites with different polarities, and Ultra Violet (UV) and fluorescence detectors can be used to detect small amounts of most compounds with a chromophore. Diode array detection is particularly relevant in connection with HPLC but can also be used with micellar capillary electrophoresis (MCE). Certain secondary metabolites fluoresce strongly and so can be detected in very low amounts with a fluorescence detector.

A suite of marine and freshwater chronic bioassays was used to characterize effluent from two pulp and paper mills using high chlorine dioxide substitution before and after conversion to oxygen delignification. One of these mills was located in the northwest U.S. and the other in the Southern U.S. Both incorporated effluent secondary treatment. For one of the mills this data set is also provided for comparison with effluent quality before the initial conversion to increased chlorine dioxide substitution. Marine bioassays included those with echinoderm sperm and eggs and larval fish. Freshwater testing included those with fathead minnows and Ceriodaphnia dubia. Concurrent chemical analysis included AOX, individual chlorinated organic compounds, resin/fatty acids, and a large number of other chemical analytes. Data are presented to characterize both the biological and chemical relevance of mill process conversions designed to reduce the usage of elemental chlorine.

Methanol is an important volatile organic compound (VOC) present in the gaseous and liquid effluents of process industries such as pulp and paper, paint manufacturing and petroleum refineries. An estimated 55,377 tonnes of methanol was emitted to the atmosphere in the year 2017 in the United States alone and at least 65% of the total emission was from the Kraft mills of the pulp and paper industries. The anaerobic biological treatment of methanol-rich gaseous and liquid effluents was tested in two bioreactor configurations, namely a biotrickling filter (BTF) and an upflow anaerobic sludge blanket (UASB) reactor. The volatile fatty acids (VFA) produced in these bioreactors were quantified and a mass balance analysis was carried out. Gas-phase methanol removal along with thiosulfate (~ 1000 mg/L) reduction was carried out for 123 d in an anoxic BTF. A maximum elimination capacity (ECmax) of 21 g/m3.h for methanol and complete removal of thiosulfate was achieved. To examine the gas-phase methanol removal along with selenate reduction, another anoxic BTF was operated for 89 d under step and continuous selenate feeding, wherein the selenate removal efficiency was > 90% and ~ 68%, respectively, during step and continuous selenate feed and a methanol ECmax of 46.4 g/m3.h was achieved. The anaerobic bioreduction of selenate coupled to methane oxidation was investigated in batch reactors and a BTF inoculated with marine sediment and operated for a period of 348 d. Complete reduction of up to 143 mg/L of step fed selenate was achieved in the BTF. Furthermore, the effect of selenate, sulfate and thiosulfate on methanol utilization for VFA production was individually examined in batch systems. For the study on liquid-phase methanol, acetogenesis of foul condensate (FC) obtained from a chemical pulping industry was tested in three UASB reactors operated at 22, 37 and 55 oC for 51 d. A maximum methanol removal efficiency of 45% in the 55 oC reactor and nearly complete removal of ethanol and acetone in all UASB reactors was achieved. Prior to acetogenesis of the FC, the UASB reactors were operated for a period of 113 d under conditions reported to induce acetogenesis of methanol-rich synthetic wastewater. The recovery of VFA was explored through adsorption studies using anion exchange resins in batch systems. The trends and capacity of adsorption of individual VFA on Amberlite IRA-67 and Dowex optipore L-493 were examined by fitting the experimental data to adsorption isotherm and kinetic models. Subsequently, a sequential batch process was tested to achieve selective separation of acetate from the VFA mixture

This chapter discusses in detail the phenomenon of biodeterioration of building materials, including aspects of microbial colonisation of their surfaces and contamination of their structures, often leading to destruction of the affected materials. The possibilities of microbial corrosion initiation were analysed, taking into account the physical (e.g. porosity) and biological (e.g. availability of organic matter necessary for proper microbial growth) features of the particular material. The characteristics of bacteria and fungi responsible for the biodeterioration of the most frequently used building materials such as wood, stone, brick, mortar, concrete, metals, paint coatings, products containing paper (wallpapers, plasterboards), glass and polyvinyl chloride (PVC) are presented, taking into account the phenomenon of microorganism succession. Major symptoms of microbial corrosion are also described in the chapter, including the most common morphological (e.g. discolouration or fibrillation) and structural (e.g. decrease in strength) changes in corroded materials.

The literature on single-cell protein production is rapidly increasing and in any review it is possible to cover all the published papers in a critical manner. Apart from waste-water treatment, the large scale production of single-cell protein represents the first major use of continuous culture techniques on an industrial scale. The use of continuous culture makes process control much easier, and in a steady state it enables measurements to be made with great accuracy over a long period of time. One of the initial steps in the development of a process for the production of single-cell protein from methane or methanol is the isolation of organisms capable of utilizing these substrates as their sole source of carbon and energy. When the growth substrate is a pure source of methane or methanol the need to use mixed cultures will largely depend on the culture supernatant organic carbon content at high productivities.

The degradation of high molecular weight (HMW) chlorinated organic material isolated from bleached kraft mill final effluent was studied using fungal strains and sunlight. Naturally occurring fungi, isolated from river biofilms, wood, and sediment samples, and two white-rot fungi, Trametes versicolor and Phanerochaete chrysosporium, were capable of degrading the HMW fraction of bleached kraft mill effluents, resulting in reductions in effluent color, adsorbable organic halogen (AOX), and molecular weight. Size distribution analysis indicated that both high and low molecular weight materials were degraded equally. Photolysis experiments revealed that filter-sterilized HMW material could be photodegraded under natural sunlight conditions, resulting in substantial losses in AOX, color, and molecular weight. Half-lives for AOX mineralization and decolorization were estimated at 10 and 21 d, respectively, during fall months. Irradiation also resulted in the release of chlorinated guaiacols and vanillins. Pretreatment of HMW chlorinated organic material with sunlight did not enhance subsequent fungal degradation.

Coagulation is a well-known, widely used process for wastewater treatment. Various coagulants have been used over the years, such as alum for commercial, large-scale water treatment plants. But there are certain disadvantages of these materials, such as large dosages, high pH sensitivity, and residual aluminum in treated water, which raises serious health concerns. Though synthetic polymers were found to be better than metallic salts on these counts, many countries across the world have laid strict regulations on the use of synthetic polymers due to their toxic nature, non-biodegradability, and residual polymer/monomers in treated water, which cause health problems. Biopolymers, on the other hand, are safe and non-toxic in nature, easily available and have shown promising results in terms of high removal efficiency and excellent selectivity toward metals and toxic substances. But their shorter shelf life and higher dosage requirement are an offset for their wide acceptance. Modifying biopolymers by “grafting” suitable monomers to their backbone structure overcome the known problems of synthetic polymers while improving the properties of the biopolymers. This chapter briefly describes the inorganic and organic polymers used for coagulation in the wastewater treatment industry, with a main focus on the more recent technology of grafted polymers.

Contamination by heavy metals, pesticides, antibiotics, dyes, and inorganic and organic compounds in water is a serious threat for human beings. In this chapter, we discuss the efficiency of biochar for wastewater treatment. The feedstock made of biochar such as pine sawdust, waste tea residue, food waste, peanut shells, rapeseed straw, seaweed biomass, rice straw, bamboo sawdust, pomelo peel, rabbit feces, date palm frond, litchi peel, wheat straw residue, chicken manure, fruit peal, municipal solid waste, etc., are very cheap as they are naturally obtained and easily available; as a result, the production cost of biochar is very low compared to other conventional adsorbents. Biochar effectively removes heavy metals, antibiotics, dye, and microbes through π-π surface complexation, electrostatic interaction, co-precipitation, ion exchange, pore filling, diffusion, hydrophobic interaction, and hydrogen bonding mechanisms. Finally, it can be said that there are gaps on research with biochar that require more attention to make it a universal material for wastewater treatment.