tailieunhanh - Nuclear Power Plant Design and Seismic Safety Considerations

Trong Ấn Độ, đá nghiền ngành Công nghiệp ước tính có hàng năm doanh thu Rs. triệu rupee (tương đương 1 tỷ USD) và do đó một khu vực kinh tế quan trọng. Lĩnh vực này được ước tính được cung cấp trực tiếp việc làm cho hơn người tham gia vào các hoạt động khác nhau như khai thác mỏ, nhà máy nghiền, vận chuyển đá khai thác và sản phẩm nghiền vv Hầu hết các các nhân viên là từ khu vực nông thôn và kinh tế lạc hậu cơ hội việc làm còn hạn chế và do đó nó mang ý nghĩa. | Nuclear Power Plant Design and Seismic Safety Considerations Anthony Andrews Specialist in Energy and Defense Policy Peter Folger Specialist in Energy and Natural Resources Policy January 12 2012 Congressional Research Service 7-5700 R41805 CRS Report for Congress------------- Prepared for Members and Committees of Congress Nuclear Power Plant Design and Seismic Safety Considerations Summary The earthquake and subsequent tsunami that devastated Japan s Fukushima Daiichi nuclear power station and the earthquake that forced the North Anna VA nuclear power plant s temporary shutdown have focused attention on the seismic criteria applied to siting and designing commercial nuclear power plants. Some Members of Congress have questioned whether nuclear plants are more vulnerable to seismic threats than previously assessed particularly given the Nuclear Regulatory Commission s NRC s ongoing reassessment of seismic risks at certain plant sites. The design and operation of commercial nuclear power plants operating in the United States vary considerably because most were custom-designed and custom-built. Boiling water reactors BWRs directly generate steam inside the reactor vessel. Pressurized water reactors PWRs use heat exchangers to convert the heat generated by the reactor core into steam outside of the reactor vessel. . utilities currently operate 104 nuclear power reactors at 65 sites in 31 states 69 are PWR designs and the 35 are BWR designs. One of the most severe operating conditions a reactor may face is a loss of coolant accident LOCA which can lead to a reactor core meltdown. The emergency core cooling system ECCS provides core cooling to minimize fuel damage by injecting large amounts of cool water containing boron borated water slows the fission process into the reactor coolant system following a pipe rupture or other water loss. The ECCS must be sized to provide adequate makeup water to compensate for a break of the largest diameter pipe in .