Produced water treatment applications

In Hydrocyclones A Solution to Produced Water Treatment, Meldrum presents the basic design principle of a dc-oilmg hydrocy leone. System design, early operational experiences, and test results on a full-scale application in the North Sea are discussed. Oil-removal efficiency was seen to rise with increasing reject ratio up to around 1%, producing acceptable outlet concentrations Early field test results on a tension leg platform in the North Sea are discussed. Preliminary data on a pumped system are also given. 

Ebrahimi M, Ashaghi KS, Engel L, WUlershausen D, Mund P, Bolduan P, and Czermak P. Characterization and application of different ceramic membranes for the oil-field produced water treatment. Desalination 2009 245 533-540. 

Application of Membrane Bioreactor Technology for Produced Water Treatment... 

Zeolites in powdered form, as they are traditionally produced, are not very useful in water treatment applications as the zeolites have to be removed from the water somehow before it is used, and removal of a fine powder (especially one which is worth saving for reuse) would be cumbersome. Also, since the concentrations of pollutants are generally low in water being treated, a relatively small amount of the adsorbent would be sufficient to treat a large stream of water. Currently, the adsorbents used to remove contaminants from water are usually used in a packed tower, and this technology is very simple and suited to the task of water treatment [7]. 

Another closed-loop control system monitors the value of the controlled variable and continuously compares this value with the desired value. When the detected value varies from a predetermined set point, the controller produces a signal indicating the degree of deviation. In many water treatment applications, this signal is sent (Figure 2-15) to a metering pump and the pump s output is automatically changed. 

Techniques for produced water treatment for toxicity reduction are still under development. Novel treatment technologies may yet be applied, but good water management of existing facilities will certainly contribute to the overall control of toxicity. Water treatment chemicals, which reduce the dispersed oil content in the effluent water, can also contribute to the toxicity of such effluent. Other chemicals used to control scale, bio-fouling, and corrosion can also contribute to effluent water toxicity, but are commonly required to reduce equipment maintenance costs. As a result, optimization of the chemicals application program can help control effluent toxicity as well as reduce the overall chemical usage costs. 

Contactor design is important in order to maximize the ozone-transfer efficiency and to minimize the net cost for treatment. The three major obstacles to efficient ozone utilization are ozone s relatively low solubility in water, the low concentrations and amounts of ozone produced from ozone generators, and the instability of ozone. Several contacting devices are currently in use including positive-pressure injectors, diffusers, and venturi units. Specific contact systems must be designed for each different application of ozone to wastewater. Further development in this area of gas-liquid contacting needs to be done despite its importance in waste treatment applications. In order to define the appropriate contactor, the following should be specified ... 

A metal, such as zinc, that forms salts with potentially weak acidic or basic properties. Limits the applicability of the metal as an inhibitor against water treatment problems. Examples are aluminum salts in water, which produce a weak base [Al(OH)3] and zinc, which may corrode at either low or high pH. 

Wastewater treatment and water purification applications employ UF in a TFF or NFF mode to produce permeate product with reduced colloids, pyrogens, and viruses. Oil droplets in wastewater are retained by UF for recycle or disposal at a significantly reduced vol-... 

The title compound is produced by treatment of 2-iodylbenzoic acid with acetic anhydride in acetic acid, and has found wide application as a mild oxidant ( Dess-Martin periodinane ) for ly and 2y alcohols. Although it appears not to be sensitive to impact, unlike the precursor acid, both explode violently when heated under confinement. The oxidant, on treatment with water is hydrolysed back to the explosive 2-iodylbenzoic acid. Forethought and caution are advised before using these explosive materials on any scale of working. 

A feature of biosensors that should be more fully appreciated by the counterterrorism community is their potential for dual use. Not only will commercial production be more sustainable if there is also a civilian application that produces a steady market demand, but users will have more confidence in a system that becomes thoroughly validated in a more predictable application. If the civilian application is one that also employs potential first responders, such as emergency room staff, veterinarians, or water treatment technicians, such individuals will more fully appreciate the value and limits of the technology. 

Over the past five years, a system for removing pesticides from the wash water produced by pesticide applicators as they clean their equipment has been developed. The system incorporates a two-stage treatment process. The first step is the flocculation/coagulation and sedimentation of the pesticide contaminated wash water. The supernatant from the first step is then passed through activated carbon columns. This paper describes the development of the system, the evaluation of the system s adequacy to handle a wide variety of pesticides, and the recommendations on the implementation of this system to commercial pesticide applicators. 

Chlorine (from the Greek chloros for yellow-green ) is the most abundant halogen (0.19 w% of the earth s crust) and plays a key role in chemical processes. The chlor-alkali industry has been in operation since the 1890s and improvements in the technology are still important and noticeable, for example, the transition from the mercury-based technology to membrane cells [60]. Most chlorine produced today is used for the manufacture of polyvinyl chloride, chloroprene, chlorinated hydrocarbons, propylene oxide, in the pulp and paper industry, in water treatment, and in disinfection processes [61]. A summary of typical redox states of chlorine, standard potentials for acidic aqueous media, and applications is given in Scheme 2. 

Two-thirds of the chlorine produced in North America is consumed by the organic chemicals industry (25% goes to ethylene dichloride production alone). Pulp and paper mills account for another 15%, while 5% of the total is used in water treatment. All of these applications, however, have environmental implications that led to demands from activist groups that the production of chlorine derivatives be reduced (even, in the extreme view, phased out entirely). While these concerns are being taken seriously in all quarters, and some chlorinated products have already been banned, the fact is that chlorine-based technologies make, and will continue to make, important positive contributions to human health and prosperity. Indeed, at the time of writing in 1996, chlorine consumption continues to rise, al-... 

The chemical intermediates adiponitrile and acrylamide have surpassed nitrile rubbers as end-use products of acrylonitrile in the United States and Japan. Adiponitrile is further converted to hexamethylenediamine (HMDA), which is used to manufacture nylon 6/6. Acrylamide is used to produce water-soluble polymers or copolymers used for paper manufacturing, waste treatment, mining applications and enhanced oil recovery (Langvardt, 1985 Brazdil, 1991). 

A growing specialty application for acrylonitrile is in the manufacture of carbon fibres. These are produced by pyrolysis of oriented polyacrylonitrile fibres and are used to reinforce composites for high-performance applications in the aircraft, defence and aerospace industries. Other minor specialty applications of acrylonitrile are in the production of fatty amines, ion exchange resins and fatty amine amides used in cosmetics, adhesives, corrosion inhibitors and water-treatment resins (Brazdil, 1991). 

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