To identify Kraft liquor effects on spermatogenesis and sperm motility of Caspian kutums by using in vitro culture, the fish testis was incubated with 5, 10 and 15 % (V/V) of liquor for 3 and 6 days. The percentage of motile spermatozoa and its total duration were also measured. Adverse effects on testicular cells were more apparent with the increase of liquor concentrations. The mean size of s...

To identify Kraft liquor effects on spermatogenesis and sperm motility of Caspian kutums by using in vitro culture, the fish testis was incubated with 5, 10 and 15 % (V/V) of liquor for 3 and 6 days. The percentage of motile spermatozoa and its total duration were also measured. Adverse effects on testicular cells were more apparent with the increase of liquor concentrations. The mean size of s...

This review analyses the advances of pretreatment with sulfide-containing liquors to modify kraft pulping. In the past several decades, modified kraft pulping has advanced rapidly, based on the principle that high sulfide content at the first stage of cooking would improve both pulp quality and the selectivity of delignification. Pretreatment of wood chips with sulfide-containing liquors (i.e.b...

Kraft mills have the potential to pre-extract hemicellulose from wood as another value added product. The impacts of pre-extracting xylan on pulp and handsheet properties, sodium and sulfur balances, and chemical make-ups in the kraft pulping process of Eucalyptus grandis were assessed. Xylan extractions using white liquor, green liquor, and NaOH were done under varying extraction times, temper...

Without reclamation of waste liquor and chemicals recovery, the kraft pulp and paper industry would constitute an enormous pollution problem. Already for economical reasons, substantial recovery is secured, however, and considerable further improvements are foreseen. Recovery is outlined in terms of cycles for sodium, calcium, sulphur, and—in a wider sense—carbon. In addition, the mechanical lo...

In this work, the effect of Fenton's reagent on the degradation of residual Kraft black liquor was investigated. The effect of Fenton's reagent on the black liquor degradation was dependent on the concentration of H2O2. At low concentrations (5 and 15 mM) of H2O2, Fenton's reagent caused the degradation of phenolic groups (6.8 and 44.8%, respectively), the reduction of reaction medium pH (18.2%...

The dynamic viscoelasticity of bamboo kraft pulping black liquor under various temperatures (ranging from 50 to 80 °C) and solids concentrations (60 to 80 wt.%) was studied. Rotational rheometer analysis data indicated that the viscoelastic motion law with a high solids concentration in black liquor was in accordance with the Kelvin model, and black liquor with a medium concentration conformed ...

I n chemical pulping a large part of the wood is dissolved during digestion. The dry matter content of the generated black liquor is typically 12 to 18 wt% [1, 2]. In the case of kraft black liquors four main groups of organic constituents are present, 30-45 wt% ligneous material, 25-35 wt% saccharinic acids, about 10 wt% formic and acetic acid, and 3-5 wt% extractives. It also contains about 1...

In all major industries increasing importance is placed on the use of instruments that analyse process streams effectively and efficiently for long periods of practically unattended operation. This helps the process operator to keep an inventory of the materials leaving the process, and check the operating efficiency. In the field of pollution, it helps to confirm that the process is operated w...

Statistics indicate that US capacities for acid and neutral suiphite pulping are presently at about the same level, running about 10000 short tons daily for each type of pulp. It is projected that acid suiphite will remain at about this level over the next ten years while the production of neutral suiphite will probably double. Most of the spent liquor from the operating mills is burned with or...