Pulping liquid applications

The side depth of the thickener is determined as the sum of the depths needea for the compression zone and for the clear zone. Normally, 1.5 to 2 m of clear liquid depth above the expected pulp level in a thickener will be sufficient for stable, effective operation. When the location of the pulp level cannot be predicted in advance or it is expected to be relatively low, a thickener sidewall depth of 2 to 3 m is usually safe. Greater depth may be used in order to provide better clarity, although in most thickener applications the improvement obtained by this means will be marginal. 

Venmri scrubbers have been applied to control PM emissions from utility, industrial, commercial, and institutional boilers fired with coal, oil, wood, and liquid waste. They have also been applied to control emission sources in the chemical, mineral products, wood, pulp and paper, rock products, and asphalt manufacrnring industries lead, aluminum, iron and steel, and gray iron production industries and to municipal solid waste incinerators. Typically, venturi scrubbers are applied where it is necessary to obtain high collection efficiencies for fine PM. Thus, they are applicable to controlling emission sources with high concentrations of submicron PM. 

Perlite and Solka-floc are finely divided powders manufactured from a volcanic mineral and from wood pulp respectively, which have filtration properties very similar to those of diatomite. Like diatomite, they are inert to a wide range of process liquids. Like diatomite, they are available in a range of particle-size distributions to give the desired clarity and flowrate in different applications. On a cost-of-use basis, they are as economical as, or more economical than, diatomite. 

The use of laboratory toxicity tests to monitor industrial effluent discharges has become a common approach to estimating the potential for environmental effects in North America and Europe. Numerous schemes have been developed to characterize and assess potential toxic effects in aquatic receiving environments. The first regulatory application of Environmental Effects Monitoring (EEM) in Canada was within the 1992 Pulp and Paper Liquid Effluent Regulations, promulgated under the Fisheries Act. A second application of EEM in Canada was within the 2002 Metal... 

Historically, a classic example of an evaporation process is the production of table salt. Maple syrup has traditionally been produced by evaporation of sap. Concentration of black liquor from pulp and paper processing constitutes a large-volume present application. Evaporators are also employed in such disparate uses as desalination of seawater, nuclear fuel reprocessing, radioactive waste treatment,preparation of boiler feed waters, and production of sodium hydroxide. They are used to concentrate stillage waste in fermentation processes, waste brines, inorganic salts in fertilizer production, and rinse liquids used in metal finishing, as well as in the production of sugar, vitamin C, caustic soda, dyes, and juice concentrates, and for solvent recovery in pharmaceutical processes. 

Emit juice clarification is the oldest and largest use of pectinase. The traditional way to prepare juices is by cmshing and pressing fruit pulp. The raw juice is a viscous liquid with a persistent cloud of cell wall fragments and protein complexes. Addition of pectinase lowers the viscosity of the juice and modifies the haze particles. These sediment and can be removed by centrifugation or (ultra)filtration. Pectin lyase or the combination of polygalacturonase with pectin esterase are found optimal for this application. 

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