Debris separation

Tocaj, A., Nandakumar, M. P., Holst, O., and Mattiasson, B. (1999). Flow injection analysis of intracellular /3-galactosidase in Escherichia coli cultivations, using an on-line system including cell disruption, debris separation and immunochemical quantification. Bioseparation 8, 255-267. 

Samples first were washed in water with manual agitation in a Buchner funnel and then were successively rinsed with methanol, chloroform, methanol, and water. During this process, particulate debris separated from the fibers, and it was assumed that loosely attached water-, methanol-, and chloroform-soluble impurities largely washed out with the filtrate. Preliminary extraction tests for the presence of synthetic dyes were conducted as follows Samples were first boiled in water. If the solution colored, the water extract was analyzed with HPLC, and the sample was then boiled in dilute ammonia. If the ammonia extracts were strongly colored (natural dyes with the exception of very few do not extract into water or dilute ammonia), they were shaken with zinc dust, and if the ammonia extract reduced to a completely colorless solution, it was concluded that the sample was an azo dye (I). Early synthetic dyes often bleed into boiling water, and azo groups will reduce in the presence of zinc dust. 

After oil is recovered from the water surface or from land, it must be temporarily stored, the water and debris separated from it, and the oil recycled or disposed of. Pumps are used to move the oil from one process to another. This chapter covers temporary storage, separation, and disposal, as well as the types of pumps used for oil. Storage, separation, and disposal are all crucial parts of a cleanup operation. In several major cleanups, recovery has actually stopped because there was no place to put the recovered oil. 

The oil is first released from the olives by crushing in pressure systems, stone mills are generally used and in continuous centrifugation plants, metal crushers (hammer, roller, disc). After it has been crashed the olive paste is mixed. Malaxation (stirring the olive mass slowly and constantly) lasts about 30 minutes. The main constituents of the paste after malaxation are olive oil, small pieces of kernel (pit), water and cellular debris. Separation is achieved by pressure, centrifugation, or selective filtration processes. 

McKellop HA. Wear modes, mechanisms, damage, and debris. Separating cause from effect in the wear of total hip replacements. In Galante JO, Rosenberg AG, Callaghan JJ, editors Total hip revision surgery. New York Rave Press, Ltd. 1995. 

Scrap from municipal refuse may be in the form of source-separated steel cans, a mixed ferrous fraction, metal magnetically separated from mixed waste or incinerator ash, and C D debris. An ASTM specification (E1134-86) was developed in 1991 for source-separated steel cans. The Steel Recycling Institute has a descriptive steel can specification entitled "Steel Can Scrap Specifications". PubHshed standards for municipal ferrous scrap also include ASTM E701-80, which defines chemical and physical test methods, and ASTM E702-85 which covers the chemical and physical requirements of ferrous scrap for several scrap-consurning industries. 

Mechanical. Premature wearout or loss of contact metal during engagement and separation can result in loss of tolerances, reduced spring forces, formation of loose metallic wear debris, which may short-circuit contacts, and development of porosity in noble metal contacts. Underplatings, contact lubricants, and hard materials reduce mechanical wear. 

Techniques used in bioseparations depend on the nature of the product (i.e., the unique properties and characteristics which provide a handle for the separation), and on its state (i.e., whether soluble or insoluble, intra- or extracellular, etc.). All early isolation and recovery steps remove whole cells, cellular debris, suspended solids, and colloidal particles, concentrate the product, and, in many cases, achieve some degree of purification, all the while maintaining high yield. For intracellular compounds, the initial harvesting of the cells is important... 

In developing a separation strategy, the size distribution of the components found in the contaminated medium can be used as a starting point. As an initial step, debris (such as rocks, etc.) can be separated from the remainder of the waste. After the debris is removed, other separation techniques can be employed to concentrate the waste further or physically manipulate the waste into a form suitable for treatment. 

Debris with particularly good absorbent qualities such as wood, some paper products, paper, cloth materials, etc., are go candidates for shredding so that they can be included in the remediation process. Materials that are not porous and are not adsorbent are glass, plastic, metal objects, some types of construction debris, tanks, etc., are good candidates for manual or magnetic separation. 

After the debris has been separated or removed, there are basically four options available for dealing with the debris ... 

Once the debris has been removed from the waste material, the preparation of the waste for treatment can begin. Over the years, the construction, mining, and manufacturing industries have developed various pieces of equipment that are geared for the specific purpMse of separating materials and making process streams uniform. The raw materials... 

Tangential crossflow filtration Process where the feed stream sweeps the membrane surface and the particulate debris is expelled, thus extending filter life. The filtrate flows through the membrane. Most commonly used in the separation of high-and-low-molecular weight matter such as in ultrapure reverse osmosis, ultrafiltration, and submicron microfiltration processes. 

Pressure-tubes allow the separate, low-pressure, heavy-water moderator to act as a backup hesit sink even if there is no water in the fuel channels. Should this fail, the calandria shell ilsdf can contain the debris, with the decay heat being transferred to the water-filled shield tank around the core. Should the severe core damage sequence progress further, the shield tank and the concrete reactor vault significantly delay the challenge to containment. Furthermore, should core melt lead to containment overpressure, the concrete containment wall will leak and reduce the possibility of catastrophic structural failure (Snell, 1990). 

Parts of the tank were projected to distances up to 360 m (1200 ft). Twenty-two pieces of the tank were recovered, constituting approximately 80% of the original tank. Debris was found clustered in two separate areas, namely, within the radii of 5° to 20° and 65° to 95° from the car s direction of movement. Three empty tank cars located up to a distance of three railroad tracks from the exploded car were blown from the rails. The undercarriage of the car was bent into a V-shape (see Figure 2.1). One person was killed in the explosion. Analysis of a recovered piece of the tank car showed that failure was due to brittle fracture. 

Another source of deposits is materials in the steam-water circuits. Acting separately or collectively as foulants and contaminants, these can pass to the boiler and combine to form deposits that stifle heat transfer. Corrosion debris from corrosion processes occurring at other points in the steam-cycle system can certainly form deposits, and the corrosion product ferric oxide (in the form of... 

Corrosion may be associated with fouling. For example, oxygen corrosion of a steam-water separator typically results in corrosion debris that builds up and fouls the separator device, thus preventing the effective separation of steam from BW. 

In small boiler systems, the use of CR system strainers and high-temperature-resistant bag filters are highly recommended to prevent this corrosion debris from entering the FW system. In larger plants, condensate polishers or electromagnetic separators may be employed. Condensate dumping may even take place, although this is a wasteful and expensive process because both water and heat are lost. 

Flocculation or clarification processes are solids-liquid separation techniques used to remove suspended solids and colloidal particles such as clays and organic debris from water, leaving it clear and bright. Certain chemicals used (such as alums) also exhibit partial dealkaliz-ing properties, which can be important given that the principal alkaline impurity removed is calcium bicarbonate—the major contributory cause of boiler and heat exchanger scales (present in scales as carbonate), although closely followed by phosphate. 

Under these conditions, because the neutralizing amine has no effect on oxygen ingress, it is common to supplement the neutralizing amine blend with a filming amine. Thefilmer may be applied separately (usually to a steam header) or blended with the neutralizers and added to the FW, or sometimes directly to the boiler. Care should be exercised when filmers are employed in previously corroded systems because it is very likely that old corrosion debris will be transported away to cause severe blockages in steam traps and valves. 

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