Exhausted pulp

Making paper without pollution requires that each part of the process be nonpolluting. The chemicals most commonly used in the production of pulp are NaOH and Na2 S. In modem paper mills, sulfur-containing by-products are scmbbed from the plant exhaust, and the aqueous sodium hydroxide is reclaimed and recycled. The fillers used to make paper opaque—titanium dioxide, calcium carbonate, and kaolin (a clay)—are natural, nonpolluting minerals. The polymer binders and sizers are relatively easy to recapture from the aqueous waste stream. 

Isoprene occurs in the environment as emissions from vegetation, particularly from deciduous forests, and as a by-product in the production of ethylene by naphtha cracking. In the United States, the total emission rate of isoprene from deciduous forests has been estimated at 4.9 tonnes per year, with greatest emissions in the summer. The global annual emission of isoprene in 1988 was estimated to be 285 000 thousand tonnes. Isoprene is produced endogenously in humans. It has also been found in tobacco smoke, gasoline, turbine and automobile exhaust, and in emissions from wood pulping, biomass combustion and rubber abrasion (United States National Library of Medicine, 1997). 

In the machine, improved by LainiS, and further perfected by Dailly, the wire sieves are retained, but the washing space is considerably extended and prolonged, though the quantity of pulp exhausted in a given time is increased. This 1b done by i... 

By such a machine as the preceding, it is stated that the pulp from one hundred and sixty hectolitres—four hundred and forty bushels—of potatoes is exhausted in twelve working hours. 

Each nitrator is equipped with two vertical agitators revolving in opposite directions, imparting motion toward the center. These agitatiors consist of a series of vertical arms, placed in such a manner, that when in motion the cotton(or wood pulp) is quickly drawn beneath the surface of acid away from the fume exhaust line... 

These may be either fresh or dried. The former are prepared for analysis by reducing them to a pulp by means of the machines used for the non-exhausted slices the latter are ground to a fine powder. As a rule only the sugar in these products is determined, but in some cases also the water. 

A number of combustion and chemical production processes contribute to environmental concentrations of PCDD/F. Sources that have traditionally caused the greatest concern include municipal waste incinerators, hospital waste incinerators, bleached chemical wood pulp and paper mills, motor vehicles and wood combustion. We have attempted to represent the most recent data available on PCDD/F emissions from these sources. It should be remembered that the list presented here is by no means exhaustive. Potential sources of TCDD not discussed in the following paragraphs include discharges from metal processing and treatment plants, copper smelting plants and pentachlorophenol production. 

Wood has also been extensively used for round and rectangular pipes, ducts and stacks for pulp mill and smelter exhaust fumes and for liquid effluent. Semicircular flumes, some with abrasion-resistant linings, have been built for the transport of mineral slurries. 

Newspapers and news magazines were not the only media to exploit and sensationalize the marihuana issue. Having exhausted the drug diaries and confessions of the hashish user genre that had been so Popular among the French, inventive novelists and pulp magazine writers saw that they could still use marihuana to sell their works. 

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