Document G5DvGZQe6DdnbBq4Dkvkevna4

$23,000"$75,000/day.* A three^eek shutdown, therefore, can mean a mil lion dollars in lost revenue. Histori cally, the trend has been toward re ducing engineering costa, Perhaps the time has come to reverse (fan ten dency. A 205b Increase in engineering manhoon may only cost the equivalent of 150 hr or less of plant operating tune oo a steep price to pay for more dependable system. Inadequate mywthdlMB poorly specified. improperly operated-- lead to startup headaeba. Shortages of boilei feedwater, incorrect water treatment, poor (aod-.often erroneous} interpretation of startup procedures -- these afl intnxhge startup problem. Moreover, process equipment usu ally receives priority during startup, -with support facilities receiving only secondary attention. Considerable work must be undertaken in getting standard* end establishing'design fpK* location* tor many types of basiesttpport facilities. Steam generators are a case fas point. Ifesigned for essentially contin uous operation, they are oot suited to the severity of swings which occur, for catample, in a refinery or chemical plant complex. Steam-generator de signer* talk in terms of 10% load change fa 3 min as bong compatible with their equipment, Rriuctandy, they will offer a 20% mssrmum load change fo 3 min, with either packagrd or flelrUrected boiler*. Additional by enpotax*. Applyio| a, ,, ^ dot. the number of failures ixtcreaw^. rapidly a integration edges qpwtriL Prom one failure tor one n|ntD3 inftiwnce, she number becomes 21 for six influences. surge capacity in the steam drum does not solve the problem. Nor does im posing Special standards or require ments, the supplier probably -wQ| refuse to quote or will quote too high with exacting specifications Wttile oot a precise rriatiooship, the curve representing this equation (pm. ceding pegs) indicates what ^ ^ expected m the way of addttioqa] costs es the degree of plant integration cresses-2 Only startup costsare shown; Increased integration how good? Ptantt are becoming more highly integrated .end cootain more soptns* (seated instrumentation than ever be fore. For compressors now are called upon to *"<** various loads oq the same frame. While eco nomics titty justify such decisions m-\ ItiaOy, augmented startup problems't can wipe out any potential savings. ' A nuithcmsticml equation has been proposed that expresses the-number of savings in initial plant cost due to bv tegration are oot reflected, A criterion of tlm type should be applied during Initial planning of ill large projects to help preset tfe amount of money required .to? plant startup. In a number of instances, protracted startups have created severe financial crises for the plant owners involved. Applying the equation re veals a need Cor'greater end greater ffcvA on engineering as plant rises posriMc upsets (Z) which may- occur <n a system as a funetioo of the degree, of integration*: where k is the number of integrated . .1 rLrinJ---- `~tnt r . ______ _ OwwfcW CiiahiMiM- Hor. X. lira, p<? 2. fMaiWOplMiwMrekiailiiOM NaW. H Mtam. Safety fa, *ir mmS Ammonia Wwrta. VoUft . AlQbt a. St>rt^reitoy Ia CMf Irv^ influences. U appears to be bom out wdv.amev^atP.twt/ou.TO.pn Ice ribbons safeguardnuclear reactor A new tea-storage system reduces the cost of containment structure* for oudear reactors by more than 20% and improves safety. This patented system uses subcooled chem ical ice ribbons developed by Flaltice Carp to condense toy steam leaks in 10 seconds or less. Compare this with the two boon or more required by wetmpray. injection and other emergency cooling systems. Conventional method of safeguarding a oudear reactor require* its placement whhin a building of sufficient sire to insure against pressure rises above 69 psifr even in the un likely event of groa rupture of the reactor coolant system. This method, e Wcstinghouse advancement, rings (he wail of the containment read with roughly 1S00 coos of ice within ao insulated cold-storage compartment. When tri"~ gered by a slight rise In pressure, doors operate automatically to open the passage between ice and reactor (drawing). The massive low-temperature heat sink thus formed reduces maximum possible transient pressure to less than 13 psig. Also; system reduces reactor containment space by 50%. Ice ribbons are harvested continuously, by peeling from a flexible freezing surface, producing ice of the same chemi cal concentration as solution from which ice wag frozen. AEC has approved the system, which soon wQ3 see service in two U-S oudear power plants. Containment system uses chemical tee solution and recycles solution to maintain subeooJed temperatures k tasulatioo. factory-scored to reduce dust production during cutting Ifstte. gets trimmed la preparation ter tostsUaflon on tank head gAir, gas and liquid handling Metal jadcats replace elderasbestos-containing finishes and jackets. reduce dust from subsurface Ireathe easier with today's insulation [TBy Walter K Hesse. Johns-Marrvilie Corp te I^Flncreasisg concern is expressed in m- But a new product, calcium silicate, igdostiy, labor, mrdirtl god government joined the high-temperature group in .^.rirdei about the high rate of asbesteaInitiated tfiirsTfii sitriiuni. lung can- the early I94CB, eventually replacing 85% magnesia and diatonmeous si t` eer and .-(rardy) mesothelioma in lica for the 300-1200-F range. Gal- Abufidiogi, industrial plants, ships, chtm silicate contained only 11% as [tfeWorkers who have begs employed for bestos fiber initially, and this later fcQ >*.orar 20 yean give special concern. to 75ft. The group of Mgb-tanpera- But titustinn b ptQng better. Cb> 3*.rider first tint the abnormally high ^ death rate of recent ytan among older ture iosalitious accounted for about 64% of the total U.S. volume. So-called low-pressure iunriatioas rmplnyir 1 Ttfrrn npimirr in sihntm were used for temperatures between v dust accumulated ovqr the past 40 SO and 250 F and contained about ** years. Thb death rate cboold diminish 75% asbestos by weigh2- These mate hmrosc the amount of asbestos dust rials tnduded air-cell sheets and pipe to which insulation Workers are ex insulation consisting of alternating posed has decreased coossdersMy over corrugated and plain asbestos paper the past two decades. The younger hooded with sodium silicate, in addi workers (fewer than 20 ytt on the tion to wool-felt sheets and pipe in. job) have had significantly less ex sulation consisting of rag and wool fi posure in comparable work periods. In the 1950Ts, practically B in- sutamms contained some asbestos fi ber paper, laminated and bnndrrf Growth of the petroleum and chemical industries tnuU up demand ber. Its content ranged from 10% for for tow-temperature insulating mate daiomaceous sflica to 100% for rial* such as foamed glass to the 1940s "mine'' cements. Latter, mixed with and 1950a By foe cad of the 1940s, wafer, were used to paint up prists in fiber-glass mutations' accounted for molded or formed block iosolntioa tod over fittings and block insulation. Today, ooeooat bydrautie setting mineral fiber cement, with only 15% asbestos-fiber content, ts common. nearly 25% of all insulation materials produced. Today, fiber-glass products bold a 50% share of the insulation market. Although' asbestos fiber pro duction increased over 400% from A popular highstempenture in- 1950 to 1965, the amount used in in suisiioD had been 85% magnesia, sulation materials decreased stigbtiy with about 14% asbestos by weight- during the same period. Power. June !**! nber-gtas* pipe tasutatfoo receive* final touche* on beflerroom piping end vatae Installation at state university plant Solid vs sprayed-on Current attacks on use of asbestos tor various purposes, preause of its hearth effects should he understood as not directed primarily at pipe and equipment tnsulstten. Efforts like those outlined in mu article have made this end-use comparatively safe. Instead, spreytng of asbestos fireproofing on the steelwork of now building* has become * malar tar get. Legislation to require substitutes for asbestos In this work ts under study and. as to the case d New VortcCKy. has been proposed for safety of workers and passersby. 11