Wool Scouring Research Articles

Biodegradation of Wool Scouring Effluent on a Laboratory Scale

A continuously fed, sequential anaerobic-aerobic-aerobic reactor system was used to treat wool scouring effluent. The chemical oxygen demand (COD) in the anaerobic reactor was reduced from 30500 mg/ℓ to 3000-5000 mg/ℓ. In the first aerobic reactor this was further reduced to 1200-1800 mg COD/l. The final discharge from the second aerobic reactor had a COD of 500-1000 mg/ℓ at a hydraulic retention time of 2-3 d. Nitrification was erratic but sufficient to reduce the ammonia-N to levels of 20 mg/ℓ and less. Mixed liquor suspended solids and volatile suspended solids could be maintained at sufficiently high levels in completely mixed systems and efficient biomass retention in the aerobic rotating biological contactor resulted in an overall removal of 98.4% COD.

Formation of Iron Sulfides during Wool Scouring and Their Effect on the Color of Scoured Wool

We propose that iron sulfides can be formed in the first bowl of a commercial wool scour. Under the low redox conditions recorded, ferric iron, a ubiquitous component of minerals on the fleece, is dissolved reductively to the ferrous form, which reacts with sulfide present either as residual depilatory on slipe wool or from degraded wool protein. The black iron sulfide may deposit on the scoured wool, making it dull and gray. The observation that some scoured wools become brighter and more yellow with time is consistent with the expected behavior of deposited iron sulfides, which slowly oxidize in air.

Industrial Application of Formed-in-Place Membrane Ultrafiltration and Automated Membrane-Forming in the Treatment and Recycle of Rinse-Water during the Scouring of Raw Wool

Fresh water consumption in the scouring of raw wool at a Mill in South Africa has been dramatically reduced by a combination of two factors, namely the purification and recycling of some of the wash water for reuse during rinsing, and the recycle of water from the firm's biological degradation ponds for use in the earlier stages of wool washing and in neutralising. Purification is undertaken by means of formed-in-place hydrous zirconium (IV) oxide membranes which are deposited automatically on porous sintered stainless steel supports. While about the same total quantity of water is used to wash the wool as traditionally, fresh water consumption on selected washlines has been reduced by approximately half.

MICROEHULSIONS IN RAW WOOL SCOURING

ABSTRACT A laboratory study on the efficiency of microemulsions to remove raw wool contaminants at ambient temperature is presented. Due to the characteristic properties of microemulsions, namely the ability to solubilize both water-soluble and oil-soluble compounds, it could be expected that they may play an important role in raw wool scouring. Microemulsions of ternary water/technical grade nonionic surfactant/hydrocarbon systems have been chosen and appropriate microemulsion compositions have been selected according to phase diagram determinations. Microemulsion efficiency has been evaluated by whiteness values, percentage of solvent extractables and optical microscopy of scoured wool. The results obtained have shown that water soluble (suint) as well as solvent soluble (grease) contaminants and probably Proteinaceous contaminant layer were efficiently removed from raw wool scoured in microemulsion media at ambient temperature.

Textile Industry Wastewaters Treatment

Effective water and waste management strategies enable us to decrease water consumption and pollution load of wastewaters. Typical examples of low-waste technologies are lanolin recovery in wool scouring, hydroxide recovery in cotton mercerizing, recovery of synthetic sizes and reuse of dye baths. Wastewaters are treated by a sequence of physical–chemical and biological processes. Traditionally, coagulation/flocculation(c/F) has been favored as the first treatment step followed by biological treatment as the second step. More recently a reverse sequence of treatment has been utilized in several cases with success. Novel technologies have been developed such as catalytic oxidation, decoloration by ozone, adsorption/desorption. Their practical use is, however, still rare. Joint treatment with municipal wastewaters has been favored wherever possible.

Recent Advances in Water Reuse Research in South Africa

Due to limited water resources, water reuse is pursued as a major component of an overall strategy to optimise water use in South Africa. Progress in South African water reuse research, mainly since 1985, is reviewed. In the field of potable reuse research, the topics addressed are epidemiological studies, activated carbon, the microbiology of reclaimed water, bioassaying, and reverse osmosis. Information is provided on the scale of direct agricultural and industrial reuse of purified sewage effluents. Indirect reuse is steadily increasing and research which traditionally addressed direct potable reuse is becoming of equal relevance to indirect reuse. In addition, research becomes necessary on problems which relate specifically to indirect reuse, such as : treatment of algal waters, variation of raw water quality, upgrading of sewage effluent quality, organohalogens, and salination problems. Recent advances in research on internal water reuse by industry focused in particular on membranes and salt removal technology. Cases mentioned are textile dyehouse, scouring, bleaching and mercerising processes; bottle washing; wool scouring; water works wash water; and power station cooling.

Analysis and anaerobic degradation of wool scouring and olive oil mill wastewaters

Two types of fatty industrial wastewaters, wool scouring effluents (WSE) and olive oil mill effluents (OME) were analysed (lipids, phenols and COD), and were then treated anaerobically in laboratory-scale fixed bed filters. Approximately 50% of the organic compounds in both wastewaters was degraded at two days of hydraulic residence time. A higher biogas production was obtained when using OME rather than WSE. This experimental study confirmed that anaerobic digestion can be considered as a roughing treatment in a multi-step process for industrial fatty wastewaters.

A New Concept in the Control of Liquor Quality in Raw-wool Scouring

A new concept in the control of liquor quality in wool scouring is described, in which the total-solids content of the liquor in the main scouring bowl is maintained at a constant preset value. This is achieved indirectly by sensing the relative density of the liquor and by obtaining positive feedback from the amount being discharged to drain. Flow rates are controlled by regulating the speed of the relevant pump monitors instead of by the more conventional method involving the use of control valves of various kinds.

Characterization of Proteinaceous Contaminants Extracted from Merino Raw Wool

This study introduces an isolation method that involves the separation of insoluble and soluble contaminants on raw wool. The contents of inorganic and organic components as well as their removal during different extraction steps are discussed, and an attempt is made to determine the most likely origin of the protein components. These investigations are of practical interest concerning optimal raw wool scouring conditions, especially with regard to the color of scoured wool and waste water treatment.

Observation of liquid transport in the ESEM

The environmental SEM (ESEM) allows the observation of liquid and liquid/solid systems in a controlled gaseous environment. In order to study the wetting properties of a wool fiber, or to understand various stages of wool scouring, a system has been devised which allows the transfer of microdroplets onto the specimen surface. A description of the microinjector device together with dynamic observations of liquid transport recorded on video cassette are reported here.Fig. 1 shows a descriptive diagram of the principle employed to transfer liquids from ambient pressure (about 1000 mbar) into the specimen chamber at hypobaric pressure (about 25 mbar). A small cavity (L) is open to the outside space via two tubes M (with 1 mm inside diameter) so that this cavity can be filled or emptied freely and quickly with a given liquid from the outside.

New Solvent Scouring for Raw Wool

We developed the new system of wool scouring which used the organic solvent. The important results obtained from the system are as follows.(1) I, I, I-trichloroethane is suitable for wool scouring with characteristic conditions for scouring, solvent removal and separating by-product.(2) Solid matters in effluent come to be reduced to on-tenth of conventional method.(3) The scoured wool obtained by our new system is longer in fiber length, less neps in top and higher yield in top-making process than the traditional system.(4) Two by-products, grease and fertilizer, are superior in quality.(5) Scouring cost is reduced to 48% of conventional case.

The measurement and sources of variation of loose wool bulk in Romney, Coopworth, and Perendale breeds

Abstract Modifications to the Wool Research Organisation of New Zealand (WRONZ) technique for loose wool bulk measurement of individual fleeces were investigated. Evidence indicates that, if care is taken in the wool scouring process, it is not necessary to degrease the scoured sample in petroleum ether. Sheep can adequately be ranked on loose wool bulk using a measurement taken at the first compression cycle. Sources of variation associated with loose wool bulk measurement have been estimated and used to calculate the numbers of animals required per treatment group to detect significant differences between groups for loose wool bulk.

Flame-Retardant, Petrol, Oil, Water, and Acid Repellent Wool

Scouring of wool in alkaline conditions in the presence of a detergent not sub stantive to wool is essential to achieve adequate oil, petrol. water, and acid repellency prior to treatment with fluorocarbons. The effectiveness of this repellent treatment depends not only on the chemical composition and concentration of the fluorocarbon, but also on the chemical Composition and physical parameters of the fabric substrate. At the same concentration of the fluorocarbon evaluated, aramid fibers produced lower repellency than wool, probably because of the more oleophilic and hydrophilic nature of the former. A decrease in the density of wool fabric appears to result in lower petrol repellency. A one-bath exhaustion treatment involving the Zirpro flame retardants and a suitable fluorocarbon imparts adequate flame retardance, oil, petrol, and water repellency to wool, including protection against dangerous chemicals and a simulated petrol bomb test, fast to at least 25 charged dry cleanings. Other flammable liquids evaluated in the simulated bomb test, such as diesel, motor oil, and their mixtures with petrol, were less severe than petrol on Zirpro and fluorocarbon treated wool, presumably because they have a higher surface tension than petrol.

Dynamic membrane ultrafiltration and hyperfiltration for the treatment of industrial effluents for water reuse

The treatment of high strength, highly fouling or hot industrial effluents by conventional membrane technology is problematic. Dynamic membranes are very versatile and have the major advantage of being replaceable in situ. Several research and development applications for the treatment of polymer manufacturing, dyeing and printing and wool scouring effluents are discussed.

Improvements in Wool Scouring to Conserve Energy and Water Use in Process'

Preliminary results of cooperative research on industrial continuous process scour ing to conserve energy and materials and to control pollution are discussed. Procedural changes are effective in reducing fuel, water, and detergent by about 25, 32, and 36% respectively, without adverse effects on the scoured wool. Grease recovery is also improved.

Effect of Metal Ions on the Photoyellowing of Wool

The yellowing of wool coptaining bound metal ions by exposure to light in the spectral range 310-500 nm has been measured with a tristimulus colorimeter. For equal doses of radiation it was found that wool samples to which ferric or cupric ions had been added yellowed more than wool containing fewer metal ions. It is suggested that special care be exercised in wool scouring to avoid metal ion contamination.

66—ROLLER-DRAFTING AS A MEANS OF ALIGNING GREASY AND SCOURED WOOLS

Roller-drafting at low drafts and ratches is quite successful in the aligning of greasy, scoured, or carded wools. Suitable scouring of aligned greasy wool results in appreciable enhancement of top yield and mean fibre length (M.F.L.) compared with conventional methods. For aligned scoured wool, the top yield and M.F.L. are similar to the values obtained by conventional methods, but after combing some slubs remain. Mechanical simplicity suggests that production rates well in excess of 100 kg/hr would be possible.

Pipe Scouring

A new wool scouring system which can take place of the conventional type has been developed. Its main characteristics are(1) the use of a pipe as a scouring bowl in which wool fleece is scoured by a stream of washing liquid, and(2) the use of air flow for the agitation of wool and liquid in the pipe.This article describes the mechanism and the scouring principle of this system and some experimental results. The main conclusion from experiments using a medium-scale test equipment is as follows; (1) Although some minor problems are left unsolved, this new system can be put into practical use as an improved wool scouring system. (2) The composition of the scouring solution and the treatment time with this method are the same as those with the ordinary method. The most appropriate air flow rate per unit time is about one fifth of the liquid flow. It should be large in the first bowl and then be gradually decreased as the wool is scoured. (3) The inclination of the pipe should be as large as possible. In the test reported here no problems occurred with tilt angles up to 8°30', which was the highest used. (4) The equipment is suitable for many uses. For example, continuous materials such as sliver or fabric pass it through smoothly without being stretched, twisted or jammed. It is therefore possible to use it for continuous wet treatments.

An Analysis of Equilibrium Conditions and Costs in Wool Scouring

An Analysis of Equilibrium Conditions and Costs in Wool Scouring

Wool Processing Oils

THE GENERAL principles of yarn production from loose textile fibres are much the same whatever the fibre. First, they are freed from impurities (e.g., wool scouring and carbonization) then mixed and blended. This is followed by attenuation and further mixing by combination of laps or slivers, followed by still more attenuation (carding) to ensure uniformity in fibre material. To eliminate very short fibres and ensure that in the sliver the fibres are all within certain length limits, further processes are employed such as gilling in worsted yarn manufacture. Further parallelization of fibres is obtained by combing (worsted yarn) and by repeated drawing or drafting until a degree of twist is necessarily introduced to continue holding the fibres together. The sliver then becomes known as roving and in this form the uniform fibre is twisted into yarn on spinning machines.