Water boron

HMSO (1979) Method 8. Boron, water soluble in soil. The Analysis of Agricultural Materials, RB 427, 2nd edn., London. 

The Analysis of Agricultural Materials, 2nd edn, R.B. 427. HMSO, London, (1979) Method 2, p. 6. Preparation of Samples of soil Method 8, p. 21. Boron, water soluble in soil Method 57, p. 134. Nitrogen in soil Method 62, p. 148. Organic matter in soil Method 63, p. 151. Particle size distribution in soil... 

On discharge from the reactors the fuel is stored for an initial cooling period in a pool at the reactor site. BWR pools are filled with demineralised water, whereas PWR pools are fdled with a dilute (typically 0.2M) boric acid solution. The boric acid in PWR pools results from mixing the boronated water in the reactor vessel with the bulk poolwater during refuelling operations. This chemistry results in BWR pools operating at approximately pH 5.8-7 and the PWR pools at pH 4.5-6. Most of these pools operate at, or below, 40°C. 

SAFETY PROFILE Poison by subcutaneous route. Powerful oxidizing agent. Mixtures with boron + water are explosive. When heated to decomposition it emits toxic fumes of F. See also FLUORIDES and SILVER COMPOUNDS. 

Or to use a design in which the core of a conventional pressurised water reactor (PWR) is enclosed within a vessel of boronated water that will flood the core if pressure is lost there is no barrier between the core and the pool of water, which in case pressure in the primary system is lost will shut the reactor down and continue to remove heat from the core by natural circulation. It is calculated that in an accident situation, replenishing of cooling fluid can be done at weekly intervals (in contrast to hours or less required for current light water reactor designs) (Harmerz, 1983 Klueh, 1986). 

Green GH, Lott MD and Weeth HJ (1973) Effects of boron-water on rats. Proc West Sec Anim Sci 24 254-258. 

Poly(vinylamine-co-vinylamine boronate) water 2009CHE... 

The accumulators filled with boronated water inject water (2x 40 m into the RCS by nitrogen pressure of 50 bars in the event of a large LOCA. 

The safety injection system, which has a large capacity, consists of 2 charging pumps, 4 high head injection pumps, 2 low head injection pumps and 2 accumulators (passive action). If a LOCA occurs, the boronated water will be made to pass into RCS by the safety injection system. 

The boronated water for safety injection is provided by the refiielling water storage tank (RWST) (1500 m ). After low level is reached in the RWST, the safely injection system is switched to recirculation, and the long term core cooling is provided. 

Diverse reactor protection system (DRPS) X Passive and active injection of boronated water... 

The outflow of primary water into the SGU tubing is compensated by pressurizer water. Boronated water enters the primary system from the upper density lock and shuts down the reactor, while depressurizing the primary system and hence stopping the primary water loss. The... 

Reactor pool (decay heat removal and fission product scrubbing) X Concrete pool containing 6000 m of cold and boronated water... 

Reactivity control Boronated water from mtermediate pool Pnmary pump tnp Passive (B) Passive (D) Boronated water enters the primaty system via density locks when unbalance occurs between generated power and extracted power or when forced circulauon is lost... 

Additional shutdown systems Boronated water injection, pump speed reduction... 

Additional data" also concern heterogeneous systems containing PuOa end UQ) in fuel pins that were made critical in water and in boronated water. Reported also are similar measurements with V(2.35)0> fuel i ns. Close agreement between calculated and observed gen-values, power distributions and rod worths was obtained."... 

To maintain the specified degree of snbcritioality for an indefinite period of time after shutdown, additional means as provided in the design may be used, such as the use of boronated water or other poisons if the temperature, xenon concentration or other transient reactivity effects cannot be compensated for by normal reactivity control devices. 

Use of warmer water may result in lower boron rejection and require feed water pH adjustment to meet stringent boron water quality targets. 

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