Abstract: A biological treatment system for removal of gaseous waste materials. The system comprises a column containing microorganisms which break down components of the waste materials; a pond in series with the column containing life forms in addition to the microorganisms in the column, which life forms provide essential nutrients for the microorganisms in the column; a treatment bed containing a reaction medium for removing undesirable biological metabolic by-products from the action of said microorganisms upon the gaseous waste materials; a fluid distribution means for circulating water between the pond, column and bed and a means for delivering gaseous waste materials through the column before such gaseous waste materials reach the pond.

Abstract: A tubular film sausage casing comprising a cellulose aminomethanate wherein from 0.5 to 30 numerical percent of the cellulose hydroxy groups have been substituted with aminomethanate groups. The casing may be crosslinked or may be fiber reinforced.

Abstract: An improvement to the process for synthesizing cellulose aminomethanate is disclosed which comprises slurring cellulose in low concentrations of aqueous caustic solutions, in the presence of urea, and steeping the slurried mixture, at from about 2.degree. C. to about -15.degree. C., for a time sufficient to permit swelling of the cellulose and uniform distribution of the urea. Cellulose aminomethanate manufactured from product prepared in accord with this process, has a uniform distribution of aminomethanate throughout the cellulose at the molecular level and comprises a suitable product for manufacturing sausage casing.

Abstract: A cellulose fiber mat sized with cellulose aminomethanate. The fiber mat is desirably an abaca fiber mat and the mat may be used as a reinforcement in products such as food casings, e.g., a sausage casing. Such a food casing comprises such a sized mat impregnated with additional cured resinous material. Such additional resinous material is desirably a cured viscose such as xanthate or cellulose aminomethanate viscose.

Abstract: This invention relates to an improvement to a process for synthesizing cellulose aminomethanate which comprises slurrying cellulose in an aqueous caustic solution, in the presence of urea; steeping the slurried mixture for a time sufficient to permit swelling of the cellulose for uniform distribution of the urea; and, neutralizing the caustic solution of the steeped slurry by treatment with an acid neutralizing solution. When cellulose aminomethanate is manufactured from product prepared in accord with this process, it has a uniform distribution of substituent throughout the cellulose at the molecular level and comprises a suitable product for manufacturing sausage casing.

Abstract: This invention relates to an improvement to a process for synthesizing cellulose aminomethanate wherein cellulose is steeped in an aqueous urea containing solution, dried to form an intimate mixture of cellulose and urea of known composition, and heated to form the cellulose aminomethanate; the improvement comprising, heating the mixture to a temperature above about 125 degrees centigrade, measuring the weight loss of the mixture during heating, comparing the measured weight loss of the mixture during heating to the weight of an equivalent amount of ammonia released in accord with the reaction path:Cell-OH+CO(NH.sub.2).sub.2 .fwdarw.Cell-OCONH.sub.2 +NH.sub.3continuing heating until the total measured weight loss corresponds to the total weight of an amount of ammonia released in the reaction when from about 30 to about 100% of the total weight of urea present in the mixture reacts with cellulose.

Abstract: A tubular film sausage casing comprising a cellulose aminomethanate wherein from 0.5 to 30 numerical percent of the cellulose hydroxy groups have been substituted with aminomethanate groups. The casing may be crosslinked or may be fiber reinforced.

Abstract: Sausage casings formed from regenerated cellulose are coated on their internal surfaces with a thin layer of a vinyl acetate polymer which is effective in causing the casing to adhere to a sausage emulsion and follow the shrinkage of the sausage during curing.

Abstract: A method for coloring synthetic food casings such as casings manufactured from cellulose and collagen wherein the tubular casing in the gel state is impregnated with a solution containing caramel and thereafter the caramel is cross-linked and insolubilized in the casing to effect permanent coloring of the casing.