Concrete vessels

Concrete nuclear reactor vessels, of the order of magnitude of 15-m (50-ft) inside diameter and length, have inner linings of steel which confine the pressure. After fabrication of the liner, the tubes for the cables or wires are put in place and the concrete is poured. High-strength reinforcing steel is used. Because there are thousands of reinforcing tendons in the concrete vessel, there is a statistical factor of safety. The failure of 1 or even 10 tendons would have little effec t on the overall structure. 

Concrete vessels were somewhat less prone to explosions sand blasting the surface reduced the incidence. 

Very large beaters (capacity 25 m3), may be used (Figs. 155 and 156). Here, the cutting drum is situated at one end of the tub which is made either of cast iron, from a couple of units to be assembled together, or of concrete. Concrete vessel are lined internally with glazed tiles. The trough is divided into two by means of a vertical baffle plate. In these compartments the bottom is inclined in opposite directions in order to facilitate the circulation of the pulp. 

In order to produce a homogeneous product, a couple of charges of nitrocellulose are blended after stabilization to make at least 10,000 kg. The mixing is carried out in various types of equipment. For instance large concrete vessels 25 m long, 4 m wide, 2 m high divided by a partition wall into two troughs, and equipped with... 

Pennwalt Corp., Pennwalt Standards For Concrete Vessels Designed to Receive Brick or Membrane and Brick Lining,Techn ca Data BMS301 (March 1974). 

Drawing 1 Concrete vessel outline, walls and bottoms contoured. Used by permission of the Pennwalt Corp. 

Typical rectangular concrete vessel design with bowed walls to keep brick lining In arch" Note design of baffle wall extending Into vessel, sides contoured and hammerhead design to keep brick lining In compression. 

The concrete vessel-whether rectangular or circular-has been completed, lined completely with a hot asphalt membrane and acid brick. If the vessel is large, an all-brick column or support for the cover may also be constructed in-... 

Some processes (e.g., water and wastewater treatment facilities) include concrete vessels plus traditional pumps, heat exchangers, and mixers. To cost such facilities, it is more realistic to report the sum of the L + M module costs and the delivery, taxes, and duties. We refer to this cost as the physical module (PM) cost. 

Research reactors are used in nuclear physics, in nuclear, analytical and structural chemistry, in radiobiology, in medicine, etc. They are usually easy to operate, inherently safe, and of moderate cost. Many of them are of the pool type the reactor core is located in the center of a stainless steel clad concrete vessel, 6—8 m deep and 2—5 m wide, containing purified water. The water provides the main radiation shielding, moderation, and cooling. The concrete walls are about 2 m thick wh a the reactor is located above groimd otherwise much thinner walls can be used. The main radiation protection demand comes from the reaction... 

UK Magnox thermal U metal nat. (0-715%) Magnox graphite CO2 (8-20) 245-400 steel/prestr. concrete vessel bled cooling of graphite... 

AGR thermal UO2 2-3%-3-5% stainless steel graphite CO2 (30-40) 334-635 prestressed concrete vessel ditto... 

Proprietary name for a pitch-like substance formulated for lining concrete vessels. 

The use of prestressed concrete vessels for gas-cooled reactors was initiated in Europe. A summary of reactor vessel designs using prestressed concrete technology is shown in Fig. 7. As indicated, vessels having... 

YuJ. Tokarev, 04. Sokolov, S.A. Skvortsov, A.M. Sidorov and L.V. Krause, A Boiling Water Reactor in a Prestressed Reinforced Concrete Vessel for an Atomic Central Heating-and-Power Plant, Nuclear Technology, Vol. 38, 1978 mid-April, pp. 221-224. 

The demolition and removal of a liner for a PCRV would be considerably simplified if it was possible to have a liner that was largely detached from the concrete vessel. 

Free standing liners have been considered In the past. Major problems with this concept are the liner being able to withstand vessel pressure and to accommodate movements across penetrations attached to both the liner and the concrete vessel. The first of these problems could be overcome by pressurising the space between the liner and the vessel concrete. 

---