Pipeline safety areas

Pipeline safety pipeline integrity management in high consequence areas (hazardous liquid pipeline operators with 500 or more miles of pipeline). In Federal Register, 49 CFR Part 195 Department of Transportation, Research, and Special Projects Administration Vol. 65 (232) 75, 378, Dec 1, 2000. 

To set the new pipeline safety zone range we should compare individual risk from gas pipeline with acceptable risk levels. This can be done using geographical information systems, where we display individual risk iso-curves on a map and than we mark spatial continuous area with risk level higher than acceptable risk level, see Fig. 3. 

A location that is specially defined in pipeline safety regulations as an area where pipeline releases could have greater consequences to health and safety or the environment. For oil pipelines, HCAs include high population areas, other population areas, commercially navigable waterways, and areas unusually sensitive to environmental damage. Regulations require a pipeline operator to take specific steps to ensure the integrity of a pipeline for which a release could affect an HCA, and thereby the protection of the HCA. 

There are three major ammonia pipelines two in the U.S. and one in the USSR. One of the American pipelines (MidAmerica Pipeline System) transports ammonia from the Texas Panhandle to points in Kansas, Nebraska and Iowa. Its total peak capacity delivered to a number of points is 8000 t/day [22]. The other U.S. pipeline, the Gulf Central Pipeline, transports anhydrous ammonia from major producers along the Texas and Louisiana Gulf Coast to points in Iowa, Illinois, Nebraska, Indiana and Missouri [23]. Further information on the maintenance and repair of the MidAmerica Pipeline System is given in [24]. The total weight of ammonia in the MidAmerica Pipeline System, when full, is approximately 20,000 tons. Lock valves are 10 miles apart so it would be possible that 400 tons could get out between lock valves [22]. It is known from [12] that in one accident 700 tons of liquid ammonia leaked from the pipeline in the USSR. In the USSR pipeline accident, the aerosol cloud of ammonia covered a forested territory about 40 km in area however, all residents in the region were evacuated in time. Pipeline operations in the U.S. are governed by the national Gas Pipeline Safety Act of 1968, as amended in 1979 [17]. 

Cross-country gas pipelines generally must odorize the normally odorless, colorless, and tasteless gas ia urban and suburban areas, as is required of gas distribution companies. Organosulfur compounds, such as mercaptans, are usually used for this purpose, and code requires that the odor must be strong enough for someone with a normal sense of smell to detect a gas leak iato air at one-fifth the lower explosive limit of gas—air mixtures. The latter is about 5%, so the odorant concentration should be about 1%, but most companies odorize more heavily than this as a safety precaution. 

Cooling water pipes are essential for the operation of power stations and must not cease to function. Pipelines for fire fighting are also important for safety reasons. Such steel pipelines are usually well coated. At areas of unavoidable damage to the pipe coating, there is an increased danger due to cell formation between steel and concrete where local corrosion rates of >1 mm a are to be expected [4], Damage to pipelines for fire fighting has frequently been observed after only a few years in service. 

Explosion Isolation For all equipment systems protected by design safety measures it is also necessary to prevent the propagation of an explosion from these protected vessels into operating areas or equipment connected via interconnecting pipeline. Such an approach is referred to as explosion isolation. 

For example, chemical engineering students studying corrosion to learn how various materials of construction may be affected by acids, alkalis, or process conditions in order to select the most economic materials for a particular use would be impacting the safety and loss prevention performance of that equipment because a vessel or pipeline leaking due to corrosion is a hazard to workers in the area. The spilled material may create an environmental hazard as well as a hazardous waste problem requiring special precautions for cleanup and disposal. 

The pipeline transport in comparison with the conventional one has several expressive advantages, especially in hardly accessible mountains and wastelands regions or in highly populated industrial areas. It can be fully mechanised and automated, it needs very low human activity in the direct contact with transported products, and it can be completely closed with a very small contact with environment, [3,4], It can transport a large quantity of material and has only negligible demands for space. It should simultaneously ensure high operational efficiency, safety and reduction of total costs of transport. 

The most serious danger that a pipeline faces is a rupture caused by uninformed digging. More pipelines mean more accidents. The tendency for C02 to remain at ground level or move into low areas creates novel safety risks that need to be evaluated for each C02 transport system at each site. Ultimately, insurance and liability issues may prove to be a constraint on C02 transport. 

Safety concerns are associated with the flammability and, sometimes, toxic properties of transported products, the high pipeline pressures (hundreds of pounds to over a thousand pounds per square inch), and the proximity to population or environmentally sensitive areas at some locations along the rights-of-way. 

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