a b s t r a c tThe major inorganic solid residues of chemical pulp mills include green liquor dregs, various lime residues, recovery boiler fly ash, and salt cake produced at the chlorine dioxide generator. Only a small proportion of these residues is currently utilized outside the mill area: landfill disposal and reuse at the mill are the most typically applied methods. The situation should be improved in the future for environmental and economical reasons. The focus of this review is on the separation of inorganic pulp mill residues to enhance the possibilities of their utilization. Solid-liquid separation operations, such as filtration and sedimentation, and the associated treatment processes, are described in close detail. The review aims at recognizing the most promising residues for utilization, as well as enhancing the understanding of the material balance of chemical pulp mills. The review also covers the most potential industrial applications for the utilization of residues, as well as the possibilities of using them as raw material in value-added products.

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Wet grinding of CaCO3 with a stirred media mill: Influence of obtained particle size distributions on pressure filtration properties,

a b s t r a c tCrizotinib was the first clinically available inhibitor of the tyrosine kinase ALK, and next-generation ALK inhibitors, such as alectinib, are now under development. Although crizotinib is generally well tolerated, severe esophageal injury has been reported as a rare but serious adverse event of crizotinib therapy. We now describe the successful treatment with alectinib of a patient who developed crizotinib-induced esophageal ulceration.

Cellulosic wastes, from sources such as low-quality cardboard and paper, are regarded as potential feedstocks for bioethanol production. One pathway from these cellulosic materials to ethanol is saccharification (hydrolysis) followed by fermentation. Saccharification is commonly performed using enzymes that are able to cleave the cellulosic structure to smaller units, preferably to glucose monomers. During the hydrolysis, mixing conditions have a considerable impact on the performance of the enzymes. Thus mixing conditions in the hydrolysis tank can also influence the downstream operations and, consequently, the overall economy of the bioethanol process. In this experimental study, four types of impeller, at different hydrolysis conditions were used. The effect of mixing on the glucose yield and on the filtration characteristics of the hydrolysate was evaluated. It was shown that not only the sugar yield depended on the mixing conditions: the effect on the solid-liquid separation step was even more significant.

The filtration properties of mineral slurries depend for instance on the properties of the solid particles and on the way how these particles arrange themselves when the filter cake is formed. In cake filtration applications, the focus is often on particle size instead of the shape of particle size distribution (PSD). The aim of this experimental study is to demonstrate the influence of the width of PSD on the properties of the filter cake in the pressure filtration of Ni-Cu mine tailings. Modification of PSD is performed by using a stirred media mill at various operational conditions. The results show that not only particle size should be considered when the filtration properties are evaluated: a significant reduction of the average specific cake resistance (> 60 %) and increase of the average porosity (almost 30 %) can be achieved by stirred media grinding at optimal conditions, in spite of reducing the median particle size. On the other hand, the selection of unfavorable grinding conditions may cause substantial increase in cake resistance. Above all, the results imply that the size of particles in the coarse end of PSD should be reduced while avoiding grinding of the finest particles. This seems to be obtainable by paying special attention to the size of the grinding medium. The main outcomes of this study will help in reducing the energy consumption of dewatering of tailings to be disposed of, and recovering valuable elements from tailings deposited in ponds, requiring the use of optimized grinding circuits and solid-liquid separation operations. However, the benefits obtained in the filtration stage should overcome the increased costs caused by the installation and energy consumption of the grinding systems. This means that the demonstrated grinding method may be profitably utilized in industrial scale only when the material is easy to grind and the filtration properties can be significantly improved, or when the filtration plant is the main bottleneck of the process.

Dry cake disposal is the preferred technique for the disposal of bauxite residue, when considering environmental issues together with possible future utilisation of the solids. In order to perform dry cake disposal in an economical way, the deliquoring of the residue must be carried out efficiently, and it is also important to wash the obtained solids well to minimise the amount of soluble soda within the solids. The study presented in this article aims at detecting the most important variables influencing the deliquoring and washing of bauxite residue, performed with a horizontal membrane filter press and by determining the optimal washing conditions. The results obtained from pilot-scale experiments are evaluated by considering the properties of the solids, for instance, the residual alkali and aluminium content, as well as the consumption of wash liquid. Two different cake washing techniques, namely classic washing and channel washing, are also used and their performances compared. The results show that cake washing can be performed successfully in a horizontal membrane filter press, and significant improvements in the recovery of alkali and aluminium can be achieved compared with pressure filtration carried out without washing, or especially compared with the more traditionally used vacuum filtration.

Enzymatic hydrolysis of lignocellulosic biomass to sugars alters the properties of the cellulosic fibers. Several process variables, including enzyme loading, play an important role in these changes. Many physical properties of fibers are affected: their length and width, porosity, specific surface area, and degree of fibrillation, for instance, may undergo dramatic changes when subjected to enzymatic degradation. In this study, the influence of enzyme loading on the fiber size was investigated using milled cardboard waste as the raw material. The effect of cellulases and hemicellulases on the monosaccharide production and the resulting fiber size was studied using commercial enzyme products. It was shown that the cellulase loading largely determined the amount of sugars produced. The fiber length was reduced during the course of hydrolysis, although the size reduction was not especially dramatic. Based on the SEM images, no significant damage to the fiber surfaces occurred during the process.