Corrosive decontaminants

The high profile of environmental considerations ensures that the development of non-corrosive decontamination systems with biodegradable components remains a high priority. The use of A-alkyl-2-pyrrolidones as the major organic biodegradable component of a hypochlorite-based liquid system has been shown to be effective in the decontamination of the major CW agents The use of strong base in A-ethyl-2-pyrrolidone has been shown to function in the same way as DS2 . 

Presently, large-diameter tanks with fixed borm stainless-steel plates are being used. Acidic process solutions and highly corrosive decontaminating soluti capable of corroding the boron stainless-steel Are... 

Monitor stock, e.g. temperature, pressure, reaction, inhibitor content, degradation of substance, deterioration of packaging or containers/corrosion, leakages, condition of label, expiry date, undesirable by-products (e.g. peroxides in ethers) Spillage control bund, spray, blanket, containment. Drain to collection pit Decontamination and first-aid provisions, e.g. neutralize/destroy, fire-fighting Contain/vent pressure generated to a safe area... 

Aldehydes, e.g. glutaraldehyde 2% (w/v), 30min at room temperature Reserved for non-corrosive treatment of delicate items Must be freshly activated Not recommended for surface decontamination due to vapour toxicity (see Table 10.5)... 

HD is locally and systemically corrosive to human tissue. Local effects include immediate inflammation of the tissues around the eyes and pronounced reddening of the skin. If not decontaminated, the reddened skin will ulcerate into watery boils within 4 to 6 hours. If the blisters are crudely broken, they will often reblister. 

Efficient refining of the more volatile actinide metals (Pu, Am, Cm, Bk, and Cf) is achieved by selective vaporization for those (Pu, Am, Cm) available in macro quantities. The metal is sublimed at the lowest possible temperature to avoid co-evaporation of the less volatile impurities and then deposited at the highest possible temperature to allow vaporization of the more volatile impurities. Deposition occurs below the melting point of the metal to avoid potential corrosion of the condenser by the liquid metal. Very good decontamination factors can be obtained for most metallic impurities. However, Ag, Ca, Be, Sn, Dy, and Ho are not separated from Am metal nor are Co, Fe, Cr, Ni, Si, Ge, Gd, Pr, Nd, Sc, Tb, and Lu from Cm and Pu metals. 

Considering the high frequency of potential chemical risk and the wide diversity of the substances that might be involved, it is important to better understand the deep mechanisms of the chemical reactivity of irritants and corrosives on the eye. This will help to optimize the management of eye chemical projections. Besides, we have learned by experience that the rapidity and efficiency of tlie emergency decontamination are decisive parameters in order to prevent the development of potentially severe lesions and after-effects due to the chemical eye bum. 

The experimental simulation of a chemical bum (Figs. 3.84 and 3.85) is stated on a corrosive such as some IM soda in contact for 3 min with the semipermeable membrane representing the cornea. It favorably shows the time gained, thanks to a solution that physically and chemically helps the pH of the aqueous humor to get back to the safe zone. Here, the point is not only to show the mechanical draining effect at the surface of the membrane/comea (which quickly restores the pH to a normal value), but also to show how the internal decontamination of a corrosive is important and difficult. The internal decontamination will deal with the amount of corrosive that might have already penetrated into the anterior chamber of the eye. 

Moreover, liquid mustard agent often foamed up and overflowed the opened projectile casings, contaminating the MDM and the surrounding area. The MDM then had to be shut down and decontaminated with a neutralizing solution, after which it had to be cleaned and the corrosive effects of agent overflow and decontamination solution repaired. 

Radioactivity transport in reactor coolant circuits involves both surface corrosion and deposition. Several XPS studies(8,9) of reactor boiler alloys have been reported which show the very strong effect of coolant chemistry on the films deposited. The chemistry of corrosion products precipitated on ZrO and Al O surfaces has been studied using XPS.ly More recently, chemical decontamination of radioactive boiler circuits has been assisted by XPS analysis of the surface-active decontaminating agent.(1 ) Surface oxidation in gas-cooled reactor circuits has also been investigated. AES has been used to follow the CC>2 oxidation of a chromium steel(H) and some pure metals. (12)... 

Several existing protocols require a solvent (acetone, methanol, isopropanol) rinse as part of equipment decontamination for VOC sampling and 1 10 percent hydrochloric or nitric acid rinse for metal analysis sampling (DOE, 1996 USACE, 1994). These practices, successful as they may be in removing trace level contaminants, create more problems than they are worth. Organic solvents are absorbed by the polymer materials used in sampling equipment construction and appear as interferences in the VOC analysis. Acid destroys the metal surfaces of soil sampling equipment and induces corrosion. The use of solvents and acids is a safety issue and it also creates additional waste streams for disposal. 

To achieve level 2, the reactor compartment is separated from the rest of the ship, sealed and stored on a ground facility located inside Cherbourg Naval Dockyard. The rest of the ship is decontaminated, controlled and sent for scrap like any conventional submarine. The reactor compartment will stay in this intermediate storage facility for roughly 15 years a duration calculated to allow enough time for short lives corrosion products to disappear, and hence reduce the radioactive dose to workers during the next phase. 

These solutions are highly corrosive and present handling, mixing, and storage problems. There is no one solution that can be utilized for the decontamination of all agents. The decon solutions are not compatible with each other and require methods of assuring the proper decon solution is available for the commodity being worked. 

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