Dike walls

A tank truck hit a pipeline leading to a group of tanks. The pipeline went over the top of the dike wall, and it broke off inside the dike. The engine of the truck ignited the spillage, starting a dike fire, which damaged or destroyed 21 tanks and 5 tank trucks. 

The water level outside the dike rose because the dike drain valve had been left open, and the dike wall was damaged by the... 

The tank, which was nearly full, contained 15.000 m of diesel oil, which surged out of the failed tank like a tsunami, washing over the dike walls. About 3,000 m3 eseaped from the site into a river that supplied drinking water for neighboring towns, disrupting supplies for a week. Fortunately no one was killed. 

At Qatar, the liquid came out with such force that it spilled over the dike wall. Conventional dike walls also have the disadvantage that a large area of liquid is exposed to the atmosphere if a leak occurs. For these reasons it is now usual to surround cryogenic storage tanks with a concrete wall, about 1 m from the tank and the full height of the tank. If the tank is not made from crack-resistant material, then the concrete wall should be designed to withstand the effects of a sudden release of liquid. 

By identifying the potential sources of failures, it is possible to develop controls to address those hazards. These controls might be passive physical items (e.g., dikes, walls, vents), active physical systems (e.g., fire suppression, pressure limiters, temperature controls), or administrative procedures. 

A fire-resistant building is located in the facility, 75 ft (23 m) from the nearest tank, and 25 ft (7.5 m) from the nearest edge of the dike wall. The building contains tank field monitoring and control equipment, provides shelter to the operators, and also houses administrative support activities. The building is equipped with multiple means of egress. 

NFPA 59A Dikes walls and drainage should conform to NFPA 30. Refers to NFPA 30. Refers to NFPA 30. 

Pipeways at grade bordered by elevated road or dike walls 1 meter (3 ft) high or > on two sides. 

Isolation valves may be located near the property line, the edge of a process unit, or the liquid outlet of a vessel. Valves should be installed on all hazardous materials lines entering or leaving the facility to ensure the facility can be isolated in the event of a spill or fire. Similarly, valves should be located at or near the battery-limit of each unit or outside dike walls for the same reasons and for safety and ease of access. 

Chamber Method. The foam chamber method for cone roof vertical cylindrical tanks consists of one or more foam chambers installed on the shell of the tank just below the roof joint. A foam solution pipe is extended from the proportioning source, outside the dike wall, to the foam maker located inside the chamber. A deflector is located inside the tank shell to deflect the discharge... 

Dike walls should be constructed of compacted earth, concrete, or solid masonry, and designed to be liquid tight. The dikes should be designed to withstand full hydrostatic head, fire, earthquake, wind, and rainfall exposure. Piping penetrations should be provided with liquid-tight expansion joints and sleeves or packing. 

Diked ASTs Fire codes dictate flammable and combustible liquid tanks have spill control in the form of dike, remote impounding, or small secondary containment tanks. The dike must contain the content of the largest tank to prevent hazardous liquids from endangering the public and property. Traditional bulk storage systems will include multiple tanks within a concrete or earthen dike wall. 

It is important to note the special design aspects of this example. Metal detection plates are installed on all sides to prevent any momentum-dominated two-phase release from going through the water spray. A two-phase release will impact the dike walls or deflection plates, causing the liquid ammonia to coalesce and rain out inside the dike, so that only vapor (without momentum) will come in contact with the water spray through the opening between the deflection plates and the tank. 

Dikes may be made of earth, steel, crushed stone, or concrete, and they may be lined with a layer of clay or asphalt, or plastic film. There are several constraints on dike material it must be chemically compatible with the process material, be durable under normal weathering conditions, have structural characteristics suitable to support loads from maintenance vehicles, and be cost effective. Ideally, to prevent ground contamination, the ground between a vessel and a dike wall should be nonporous. 

Assessing the effects of enclosures or vapor boxes is similar to assessing the effects of vapor fences. Consider the case of a typical dike sized to hold 110 percent of the liquid spilled. For small releases, the dike walls would act as containment or storage for the vapor generated shortly after release occurred. The vapor that would be generated by evaporation or boiling from the dike floor would displace the air in the dike for a given period of time and then overflow the dike walls. The vapor holdup duration is easily estimated ... 

Structures building footings, dike walls, sumps pits 20 1,000... 

Dike walls 4 ft. high 0.50 CY/ ft. Table 19.5 Columns Foundations... 

The homblendite veins are ascribed to fluid-assisted fracturing of the dike wall rocks and infiltration of volatile-rich melts in branching and anastomosing cracks. Conversely, the low-alumina pyroxenites from Ronda (Garrido and Bodinier,... 

After a period of use, three leaks developed close to each other at the outer base of one of the dike walls. Chemical grouting was selected as the method for sealing the leaks and for preventing the formation of new leaks along the entire length of the dike wall that was leaking. 

The flap valve should be operable, be chain, at the curb or dike wall and should be closed at all times except to drain surface water from the enclosure sifter rain storms. Instead of the flap valve, a gate valve may be used for containing contents of the enclosure. The gate valve should be installed in the sewer line, outside of the enclosure and be provided with an extension stem for operation at grade level. 

Incompatible wastes and materials must not be placed in the same pile unless separated or protected by means of a dike, wall, berm, or other device. A hazardous waste may be subjected to land disposal in compliance with RCRA regulations. The landfill must have a liner system to the adjacent subsurface soil or groundwater or surface water. 

If a chlorine storage tank is simply diked, a low wall may be sufficient for containment, but the area available for vaporization of chlorine and for transfer of heat to the chlorine from the air and the ground will be relatively very high. Better control of the vaporization process results when the floor under the storage tank is sloped and the liquid is collected into a deeper sump of smaller area. Dike walls should always be vertical or nearly so in order to prevent spillover of chlorine due to wave action or its initial momentum. 

The growing vapor cloud formed by the mixtiue of gasoline and air flowed over the dike wall, dispersed and flowed west off-site toward the Maylands Industrial Estate. Gasoline is easily ignited, but the vapor does not easily explode in open-air situatiorrs. However, up to 300 British tons (336 US tons) of gasoline spilled over from the top of the tank. It is estimated that about 10% (30 British tons) (3.4 US tons) vaporized and mixed with the cold air eventually creating flammable concentrations capable of supporting combustion [5]. 

Soils Rood site with copious amounts of water and neutralize with dilute sodium hydroxide, special foams, or soda ash. Keep away from water sources and sewers. BuUd barriers such as dikes, walls, and lagoons to contain spills. 

FIGURE 2-17. Standard Dike Arrangement. Height is usually restricted to six feet. When the dike is higher, the distance between a tank and the toe of the interior of the dike wall must be at least five... 

Locating pumps inside a concrete diked wall is common in many proce.ss plants. The apprtxich shown in Exhibit 15-35 shows the pump block. set at the. same elevation as the dike. With thi.s configuration, the... 

Lines penetrating concrete dike walls may be secured against leakage by using commonly available seals. The design shown in Exhibit 15-37 permits minor axial movement The seal shown in Exhibit 15-38 is used when an insulated line runs through a larger... 

Another way of injeaing foam into a tank is shown in Exhibit 15-50. Foam concentrate from a truck or tank is supplied to a foam maker located outside the dike wall. The foam may be injeaed into the regular produa transfer piping or routed directly to the stor-... 

A diked area drain is shown in Exhibit 13-45. Because dikes are designed to hold the contents of a storage vessel in the event of a rupture, area drains must be kqx closed at all times. A drain valve operates just outside the dike wall so that plant personnel can see when the contents have been drained and the valve may be redosed. 

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