Dump tanks

Many redundant safety features were provided at the SRP. These included a moderator dump tank, gadolinium nitrate solution as emergency absorber, continuously mnning diesel generators, and a 95 x 10 -L (25 x 10 -gal) elevated water tank for each reactor, for assurance of cooling. 

Provide for addition of diluent, poison, or inhibitor directly to reactor. Provide for automatic or manual actuation of bottom discharge valve to drop batch into a dump tank with diluent, poison or inhibitor, or to an emergency containment area. 

Transfer reactor contents to dump tank with diluent quench. 

The discharge of copious quantities of chemicals directly to the atmosphere can give rise to secondary hazards, especially if the materials are toxic and can form a flammable atmosphere (e.g., vapor or mist) in air. In such cases, the provision of a knockout device (scrubber, dump tank) of adequate size to contain the aerated/foaming fluid is required. 

About half of the confinement failures are caused by hydrogen combustion in an ECCS effluent dump tank. Inerting the atmosphere in this tank would further reduce the confinement failure rate. 

Evaporative cooling to maintain the reaction mass under control. Dumping (dump-tanks as safe discharging areas) of the reaction mass or quenching (thermal inhibitors) can be used. 

Steam and Water Dump Dump Valves Dump Tank... 

While normal vents from a distillation unit may be routed via the feedstock tank, a dedicated dump tank should be provided if there is a serious risk of an exotherm being discharged through the safety valve. 

As with the glass apparatus, the pressure Dewar calorimeter can be fitted with a stirrer, connections for additions and sampling, pressure and temperature sensors, and jackets for heating or cooling. It can also be connected to a dump tank for the investigation of tempering reactions (Figure 3.11) (Sections... 

If we assume that the reaction rate of 35 W kg" at 90°C doubles with every 10 K rise in temperature then at the boiling point (140°C) the rate will be an uncontrollable 1120 W kg". There are many engineering solutions to this potential hazard dump tanks, quenching, independent high-capacity condensers, venting to a catch tank and so on. All of these solutions are expensive and must work reliably on the rare occasions they will be required. 

In the event of an alarm, an automatic sequence of actions should make the plant safe without the intervention of an operator. The sequence is likely to be simplest for continuous or semi-batch processes typically it may involve no more than stopping the reactant feeds, provided there are no problems with accumulation of reactants. Batch reactors are more difficult, particularly if they contain large amounts of unreacted material and are more likely to require the provision of protective measures such as emergency relief venting, or the provision of dump tanks with drown out facilities. 

Where there is direct evidence that surface-active foaming behaviour does not occur, it is possible to take advantage of any disengagement which may occur in the vessel. This is unlikely to have much effect on the required vent area, but it can considerably reduce the complexity and cost of downstream equipment such as dump tanks and scrubbers. 

The cooling water supply to a condenser was blocked by pebbles and the operator did not turn on the emergency cooling system to the reactor jacket. However, when the runaway started the reactor contents were safely emptied to a dump tank. 

A pass-through dump tank, fumigation chamber, or an equivalent decontamination method is to be provided so that materials and equipment that cannot be decontaminated in the autoclave can be safely removed from the facility. 

Figure 1 shows the schematic diagram of a water-nitrogen two-phase flow blowdown facility. The facility consists of the upstream tank, the test section and the downstream dump tank. The detail of the test section is shown in Fig. 2. The nitrogen-gas is supplied by a bomb, and it passes through a pressure regulator and a flowmeter and then blows out through a sintered metal ring on the head of the injector.

Fig. 3. PSDF of pressure fluctuation at four measuring points for gas flow rate = 2.12 x 10-% /s, pressure in usptream tank = 0.1 MPa, pressure in downstream dump tank = 0.074 MPa (left column) and 0.034 MPa (right column).

EMP of the cooling circuit 2-air coder 3-dump tank 4-cooler 5,7-cold traps 6-experimental mockup 8-EMP of the sodium circuit 9-calibration section 10-preheater 11 -electric supply. 

The system is intended to prevent inadmissible increase of pressure in the primary circuit if all subsystems for residual heat removal fail following the reactor shutdown. Primary circuit emergency pressure decrease is provided by two systems. The first system consists of two sets of safety devices (SD) and of a 1.6 m cooled dump tank. When the primary circuit pressure reaches 19.6 MPa the SD actuates automatically and discharges a portion of coolant into the dump tank. The system can be used repeatedly following dump tank drainage. Automatic membrane safety devices (ASD) are provided to protect the primary circuit against damage in case... 

A sodium leak detection system provides early warning of any sodium-to-air leaks from the IHTS piping. In the event of an SG tube leak, the sodium-water reaction pressure relief subsystem (SWRPRS) provides overpressure protection of the IHTS and IHXs. The SWRPRS consists of a safety-grade rupture disk, a sodium dump tank, a cyclone/separator tank, a vent stack, and a hydrogen igniter. To separate the reactants, the SWRPRS also initiates the water-side isolation of the SGS and pressure relief. 

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