POWER STATION

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 SI mm a are to be expected [4]. Damage to pipelines for fire fighting has frequently been observed after only a few years in service. 

External measuring probes were installed at the pipeline wall entrance points. The potentials of the measuring probes and the currents flowing between the probes 

Power station (Section Copper grounding grid 2000 10 20 Refinery (Section 12.4)  

3) Deep resistance current Anode Deep resistance Current Anode 

To ensure long durability, electrical grounding equipment in power stations is constructed of corrosion-resistant materials that have a very positive rest potential (e.g., copper with = -0.1 to -0.2 V). These grounds, like steel in con- 

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This situation has recently arisen in the UK where competition for gas sales has been encouraged. Gas producers can enter into direct agreements with consumers (ranging from power stations to domestic users), using the national distribution grid if necessary. The impact of this change on gas price has been significant a reduction of around 60% in the period of a year. 

Outlet Superheater (SH) header of Unit 3 (600 MW. supercritical multi-fuel l of an ENEL power station it consists of 2 twin and independent bodies (22 m length, 488.5 mjn internal diameter, 76.2 mm thickness material SA 430 TP 321H stairdess steel). This header has suffered from relevant cracking problems in assembly welds after 108.000 hours of service and... 

Outlet Superheater (SHI header of Unit 4 (600 MW. supercritical multi-fliel l of an ENEL power station it also consists of 2 twin and independent bodies (23 m length, 215 mm internal diameter, 103 mm thickness material ASTM A335 P22 - 2.25CrlMo - low alloy). Structural integrity problems and monitoring requirements and objectives same as above. 

The paper presents the results from systematic comparisons of contrast and resolution obtained with different types of radiation sources on steel thicknesses from 5 to 40 mm. These results have been taken into account with the definitions of the European standard for radiographic inspection of weldments (EN 1435) that is approved since 1997. Conclusions from practical investigations on pipe line sites, in petrochcemical plants and in nuclear power stations will be discussed as well. Furthermore, the presentation will stipulate a variety of advantages obtained from the new source in terras of coUimation and radiation protection. 

The pulser/receiver HILL-SCAN 30XX boards satisfy DIN 25450. Typical applications are ultrasonie imaging systems for nuclear power stations and for aircraft, material characterization, transducer qualification, replacement of portable flaw detectors (inspections of welded joints), inspection of new materials, measurement systems with air eoupling. ... 

Ukraine has five nuclear power stations with fifteen reactors with a total power output of 13.6 thousand MW (13 reactors of WWR type and 2 reactors of RBMK type in the Chernobyl NFS). In addition there are 47 thermal power stations with a total power output of 32.4 thousand MW, 6 large hydraulic power stations on the Dnieper and 55 small stations on other rivers. 

J. Backersgard - SAQ Kontroll, Sweden. J. Gunn, Longview Inspection, USA. POWER STATIONS... 

The non destructive department of Laborelec is mainly involved with problems concerning nuclear, thermal and combined cycle power stations. Our inspections are based on eddy current and ultrasonic testing. 

When the power station is working at normal load, RCCA s are in their upper position. This position is ensured by guide eards and a continuous guide. The 6 to 10 eards maintaining the horizontal position of each rods are equally spread in the upper internals of the reactor. 

Many problems have plagued steam generators of nuclear power plants over the last decades. Therefore, Laborelec developed its own inspection equipment and services. These were extended to other components of nuclear plants like thimbles, guide cards and baffle bolts and to classical parts of power stations like turbines, alternators, heat exchangers and piping. 

MSW incinerators (qv) are typically designed to reduce the volume of soHd waste and to generate electricity in condensing power stations. Incineration of unprocessed municipal waste alone recovers energy from about 34,500 t/d or 109 million metric tons of MSW aimuaHy in some 74 incinerators throughout the United States. This represents 1.1 EJ (1.05 x 10 Btu) of energy recovered aimuaHy (18). Additionally there are some 20 RDE facihties processing from 200 to 2000 t/d of MSW into a more refined fuel (19). Representative projects are shown in Table 10. 

Lead bricks are generahy used as temporary shields for radiation sources at nuclear power stations, research institutes, hospitals, and fuel reprocessing plants. Plat, rectangular bricks requite a double layer with staggered seams whereas the interlocking bricks requite only one course. Lead shot can be poured into inaccessible areas like a Hquid. 

As of 1994 there were 105 operating commercial nuclear power stations in the United States (1) (see Power generation). AH of these faciUties were light, ie, hydrogen—water reactors. Seventy-one were pressurized water reactors (PWRs) the remainder were boiling water reactors (BWRs). 

Recirculating Ste m Generator. The corrosion performance of many RSGs in commercial power stations in the United States has been marginal (2). Many tube bundles have had to be replaced. Many tubes have been plugged or sleeved with inserts as a result of excessive corrosion on the secondary side. 

The 1990 Amendments to the U.S. Clean Air Act require a 50% reduction of sulfur dioxide emissions by the year 2000. Electric power stations are beheved to be the source of 70% of all sulfur dioxide emissions (see Power generation). As of the mid-1990s, no utiUties were recovering commercial quantities of elemental sulfur ia the United States. Two projects had been aimounced Tampa Electric Company s plan to recover 75,000—90,000 metric tons of sulfuric acid (25,000—30,000 metric tons sulfur equivalent) aimuaHy at its power plant ia Polk County, Elorida, and a full-scale sulfur recovery system to be iastaHed at PSl Energy s Wabash River generating station ia Terre Haute, Indiana. Completed ia 1995, the Terre Haute plant should recover about 14,000 t/yr of elemental sulfur. 

Other Uses. Other uses include intermediate chemical products. Overall, these uses account for 15—20% of sulfur consumption, largely in the form of sulfuric acid but also some elemental sulfur that is used directly, as in mbber vulcanization. Sulfur is also converted to sulfur trioxide and thiosulfate for use in improving the efficiency of electrostatic precipitators and limestone/lime wet flue-gas desulfurization systems at power stations (68). These miscellaneous uses, especially those involving sulfuric acid, are intimately associated with practically all elements of the industrial and chemical complexes worldwide. 

Initially, the source of environmental risk from cooling water was assumed to be the pollutant discharged, ie, heat, in the form of the elevated temperature of the water released from the condensers. Heat is now recognized as being only one of several potential risks of power station cooling (Fig. 2). 

Fig. 2. Sources of potential biological damage in the immediate vicinity of a power station cooling system where the condenser may sustain mechanical...

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