Liquored soaps

Black Liquor Soap Recovery. Black Hquor soap consists of the sodium salts of the resin and fatty acids with small amounts of unsaponifiables. The soap is most easily separated from the black Hquor by skimming at an intermediate stage, when the black Hquor is evaporated to 25% soHds (7). At this soHds level, the soap rises in the skimmer at a rate of 0.76 m/h. At higher soHds concentrations, the tall oil soap is less soluble, but higher viscosity lowers the soap rise rate and increases the necessary residence times in the soap skimmer beyond 3—4 hours. The time required for soap recovery can be reduced by installing baffles, by the use of chemical flocculants (8,9), and by air injection into the suction side of the soap skimmer feed pump. Soap density is controUed by the rate of air injection. Optimum results (70% skimmer efficiency) are obtained at a soap density of 0.84 kg/L (7 lb/gal). This soap has a minimum residual black Hquor content of 15% (10—12). 

Black Liquor Soap Acidulation. Only two-thirds of a typical black Hquor soap consists of the sodium salts of fatty acids and resin acids (rosin). These acids are layered in a Hquid crystal fashion. In between these layers is black Hquor at the concentration of the soap skimmer, with various impurities, such as sodium carbonate, sodium sulfide, sodium sulfate, sodium hydroxide, sodium Hgnate, and calcium salts. This makes up the remaining one-third of the soap. Cmde tall oil is generated by acidifying the black Hquor soap with 30% sulfuric acid to a pH of 3. This is usually done in a vessel at 95°C with 20—30 minutes of vigorous agitation. Caution should be taken to scmb the hydrogen sulfide from the exhaust gas. 

CTO prices are closely tied to the cycles of the U.S. economy and the paper industry. They vary between 120 and 220 per metric ton. In 1995 they were close to 200/t (4). With 50% of pine wood being converted to linerboard valued at 400— 600 per ton, pulp manufacturers do not focus on optimum black liquor soap recovery, which only amounts of 60—70 kg/1 of southern pine pulp. This soap is converted to 30—35 kg of CTO, worth 6— 7 or less than a little over 1% of the pulp value (5). This recovery is only 45% of the CTO available in the pine tree. With more care and higher CTO prices, 10—15 kg of additional CTO could be obtained per ton of pulp (6). 

The amount of water to be evaporated is calculated from the amount of liquor (soap lye or Sweetwater) and its glycerol concentration. Table 1 shows the... 

Blue and Grey Mottled Soaps.—These are silicated or liquored soaps in which the natural mottling, due to the impure materials used in the early days of soap-making, is imitated by artificial mottling, and are, consequently, entirely different to curd mottled soaps. 

Sterols are synthesized in both plants and animals. Sterols and their derivatives, such as hormones and vitamin D2, perform various important functions in living organisms depending on their structure. Consequently, sterol products can be derived from several sources. Plant sterols, or phytosterols, are obtained from the unsaponifiable fraction of vegetable oils and fats. The amount of sterol, as well as its composition including fraction of unsaponifiable portion of the respective oil and fats, depends on the raw materials and is characteristic of the particular base material (Table 1). Soya oil represents a widely available source for commercial production of phytosterols. The unsaponifiable portion is separated into a sterol fraction and a tocopherol fraction. A small amount of tocopherol is usually left in the sterol fraction (approximately 4%), which acts as a natural antioxidant in the final product [2]. Plant sterols are also obtained from the black-liquor soap skimming in commercial pulping of wood. The neutral fraction of this so-called tall oil is relatively rich in sterols (approximately 32% of the neutral fraction [3]), and the sterol... 

Tyj)e of dryer Applicable with dry-product recirculation True and colloidal solutions emulsions. Examples inorganic salt solutions, extracts, milk, blood, waste liquors, rubber latex, etc. Pumpable suspensions. Examples pigment slurries, soap and detergents, calcium carbonate, bentonite, clay sbp, lead concentrates, etc. does not dust. Recirculation of product may prevent sticking Examples filter-press cakes, sedimentation sludges, centrifuged sobds, starch, etc. 

Tall oil rosin is obtained from crude tall oil obtained from the Kraft (sulphate) pulping of various coniferous trees in the paper manufacturing industry. During the Kraft pulping process the fatty acids and the resin acids from the coniferous wood are saponified by the alkaline medium. On concentration of the resulting pulping liquor, the sodium soap of these mixed acids rises to the surface from where they are skimmed out. By acidification of this material with sulphuric acid, the crude tall oil is obtained. Fractional steam distillation of the crude tall oil allows the separation of the tall oil fatty acids and the tall oil rosins [21]. 

Abrichtelauge. /. (Soap) weak caustic liquor, abrichten, v.t. fit, adjust, true train. 

In soap-making some use is made of the molybdenum-bearing type for dealing with glycerine recovery from soap liquors containing sodium chloride. 

Process contaminants such as black liquor or saponified organic oils (soaps). 

However, the ability to act as a builder encompasses much more than so far been mentioned. Builders influence the coagulation of solid soil, often form a buffer system, and promote the soil suspending activity of washing liquors. They are further able to reduce the catalytic effect of ferric and manganic ions. Thus they support the stabilization of peroxides in detergents. Similarly, rancidness caused by catalytic processes of soap and fragrances can be avoided. 

The contactor finds extensive use where high performance phase separation and countercurrent extraction or washing in the one unit are required. Particularly important applications are the removal of acid sludges from hydrocarbons, shown in Figure 13.40, hydrogen peroxide extraction, sulphonate soap and antibiotics extraction, the extraction of rare earths such as uranium and vanadium from leach liquors, and the washing of refined edible oils. 

Moderate Soap handling Talloil soap was being fired separately from black liquor when weak black liquor beneath soap entered pump suction... 

A number of studies have evaluated the toxicity of pulping hquors, in particular the black liquors generated from Kraft mills. Table 8 shows a partial representation of toxicity data compiled by the NCASI (National Council of the Paper Industry for Air and Stream Improvement) and McKee and Wolf for Kraft mill pulping wastewaters [15,16]. The table indicates that hydrogen sulfide, methyl mercaptan, crude sulfate soap, and salts of fatty and resin acids are particularly... 

Two other important side products of the kraft process are sulfate turpentine and tall oil. The turpentine is obtained from the gases formed in the digestion process. From 2-10 gal of turpentine can be obtained per ton of pulp. Tall oil soap is a black viscous liquid of rosin and fatty acids that can be separated from the black liquor by centrifuging. Acidification gives tall oil. These side products will be discussed later. 

Recovery from the spent lye liquor obrd on saponification of fats and oils in the soap industry... 

---