Project Engineering of Process Plants

Project Engineering of Process Plants

(Parte 2 de 10)

Before proceeding with any plant location study, one must have a complete knowledge of the existing company organization, history, cost data, and marketing techniques. Just as a family must know its

8 Project Engineering of Procerr Plants rit I [)nr!,l~:i-i!~:: :i I(.\V I~u-1% so :I colmpitny 1-1 :rls(~ knoll- itticlf lhciorc locating :I new plant. r\cquiririg such knor~-- ledge, l~owrer, is not :~ln-ays easy. In the fast gr~~ving IWJW-s ill- dustry, many organizntionc have grown ir~mi ?mall family-orvned con- cerns iuto lnrge corpurate mterprises in a short span r~f ye:lrs. ('Iwlr- ('ut ,~rg:~nization and lroli,,y ~Ftcn fail to (lrfinr:il <Iririnx -1.1 no~ucnal periods of grun-th. It is vell wxth vhile fur a cornlxtny in this situation to attempt definition of policy and organiz:~tion Ilciore proceeding ni!!l cxpanbion in nrrv areas. In devising a TI-\-orkahle llrocednre for a plmt, location study. soulc em~proniisc ulust he made betmcn tlvu extremes. One, an exlianstiv<, .statistical study requiring a decade for conipletion and the other, :I short-cut study heavily weighted wit11 preconceived icleas m~d lacking in ohjectirit?-. A complete study of thousancls of possi!)lc locations i. of emme, out of the question. Some rneans of decreasing the nuuilm of 1mssibilities nus st hc found. .%ires1 has suggcstcd the niethod of allparent nss<~cintion. A surrey of existing plants of the type being co~uidered ~vill often indicatc th:it ccrtirin types of locations 11aw hew referred in the 11a.t. Questioning of the ~nanngemmt of tlicsc plants niay indicatc spccial considerations ~11icli dictxted such locations. I11 this nianner, it niay bc possible to rcstrict the *tudy to several genrral areas.

1Iany processrs have one or more predominant factors vhich serve to uiinirnize the nunibcr of possibilities for plant location. Raw ~nntcrial and transportation costs may 11c such that n p1:lnt must be located near a source. This ~vill suto~natici~lly rcducc the sitvs studiecl to those ncnr sources of raw ~naterixl, rrliich nlay be i1nl3- st,vernl in u~nbrr. Labor require~nmts may be such that citics klo~ rertain size must l!v ~~xrlrnlcd, because only n larger city can supply the hrgr 1;ibor rcquirc- nients, l'l~ese and other f:ictors s~rw :IS eKective scrcming i~~cnts ~vl~ich .wve 110th tinic and n~mey.

Haring derided upon scvcrnl por.;il~lr regions for pl;~nt l~~cation, the nrxt step is a dct:iilctl -tudy of tlic possiblc locations. This study in- clndee a survey of all tht: important f:tctors involved, arld n cost stody. It is not possihlc to assign dollar value.? to all the factors that uiust bc considered. Such intangible factor*: however, can often he conlparerl by assigning each a numerical valne (100, 200. 300. ctc) the size of 1r.hic11 depends upon tl~c importance attadled to the particular itcn~ bciug considered. The assigning of the nutnerical values is bard 011 opjniou, hut such opinion can bc agreed upon by the management at tl~c outset of the study no ns to insure an objective nppraacl~ to the accumula- tion and preseutatirln of data. After the dctailecl study of sevewl arras indicates a partirulnr

Plant Locotion 9 region or corninunity as being idedly suited. thcn a specific site in t11:it rcgion must be selected. Yasecnl" has emphasized the importance ui ~lctern~ininp the specific site after the conilnunity has been sclcctcd. -

If dur~ng the study of sewral comn~unities a particular site in one is found that has nnwual appeal. tlir eutire stndy may he influenced by it. Such ~nflucncc in effwt yres undue ~vriyl~t to the sitc itself, I~eearrsc it is so ofte~i pwsible for ouc or more individuals to fa\-or thc appear- :tncc ui :I gixn sitc and 11lace excessive enlplia?is on its iuq~ortancc.

Row Materials r Ihe selection of the sonrce of r:1~1- nmatcrials, :rlthough it nlny not be at the plant site, is an rxtrrmely ini]~ortant factor in tl~c ulti~natc I<]cation of the plant. In many cases, the stud?- of the ra~ material situation m:ly ~~rece(lc tlic analysis of t,l~e other plant lowtionnl facturr, sinec pilot plant 7vol.k on a. p~cs requires at least n knon.leilge of tl~r ultimate ~:IK uiilterial supply. Process devclop~nent ~ork and econ~~niic studies dl indicate the mininmn~ stantlartl~ for rurv ~uatc,rinl selection. Once thcse st:.ntlards arc dcterminctl, then all possible sonrrer of :~cccpt-

:i~le rax ninterials can be located :md more rlet:lilcd analysis of thc source; ran prorccd.

The extent of each raw riiatcrinl source must be determined in tlic light of existing and estimated future requiremmts. .In attc~npt to estimate the life of tllc ra~v inaterial source hasctl on fntnre require- ~ncnts niust be made. Alternate sourccs or substitutes in tl~c area sln~uld also hc located and evaluated. The rost of SCIK matrrial de- livered to tllc plant site can then he dctermined for a11 tlmsc sources mectiug thc quality and quant,ity specifications required by the process.

.Iccuratti frcigl~t rates must be used in determining thcse costs. Bc- cause ol tlic conlplex freight ratc strncture that exists in tlic United

States, it is not 1111ssiblc to use soul? sinq~lc dol1:ir 11er mile figurt, iscc IJC!IJ\\-I. A ~rl:~~si~~;~l rule statt,~ tlnlt if thv raw 111xtcrix1 lo>cs ~al>i,lc~r- ;ibk woigllt during processing tu the fimil product,, it is cheaper to loetitc the plant at the source of the raw material. As is true, hon-ever, wit11 all sue11 general rules, there arc a nun~bcr uf notable cxccptions. X ~lrlivere,l ran- nintcrial cost analysis sliould nlwiy~ IF n1:idr for e;tch

111nnt lw~tiuu being wn~id<,rcd

10 Project Engineering of Process Plants


.is stated previously, no simple dollar per nlile cost rule can be ap- plied to freight rates. Railroad freight rates in particular are cx- trcmcly complex. An example given hy Yaseen'Vllustrates this complexity most effectively. He describes a nianufacturer din is

~'onsidcring a central Ohio location for a nen. plant and who has dis- tribution in surrounding territory and also in the 1.0s Angeles area. A rnajor imnpetitor is located in Cleveland, Ohio. Considering Jlarysville as a locatim. it is found tlrat the freight rate per hundred pounds will he $556 to Lns .Angeles. The rate fn)m Cleveland is the same, h loca- tion in Pcnria, Ohio, only scvcn miles furthcr west of hlarysrille ill enjoy a rate of $4.83 per hundred pounds producing an advantage over tlrc (Ilevelmd ro~npctitur.

It is not possible to prcscnt a coniplete discussion of freight rates in this rhaptcr. The engineer in charge of obtaining information re- latcd to plant location need mly realize that transpr~rtation experts must bc cousultcd in crtnblishing freight charges and optimum location lvith rtqect to transportation. Such expert information is available from the frrigllt agents and traffic cxpcrts of tlrc railroads and othcr transportation facilitic;. In addition, thc traffic manager of one's own rompany can l~e of great assistance in obtaining the necessary inforwa- tion and aiding in its interpretation.

The effect of transportation facilities and ratc.; on plant location van he a rontrolliug factor, Industries such as the plastic industry, for instance, 15-hich must dclivcr many small slripnients to various users in the miniurum of time, find location near the majority of users inanda- tory. I,t,s-tl~an-car-Itlad-lot (LCL) rates are very high; and, there- fore. the distanre that the material must he shipl)ed should be kept to a minimum.

Railroad Freight

Although truck transportation has increased inarkeitly in tlrc past tcn or fifteen ytm" it is safe to say that fcrv process plants could exist ivitlir~ut awess to at lcast one milroad. The railri~ads continuc to carr? the hulk of industrial products. Disrnssions 5~1th railroad freight agents conwrning frcight rates ant1 methods of handling in the various ronimunitics under consideration are necessary if a true picture i~ to hc ihtainrd for comparing the relativc advantages of *everal locations.

A .study of the railroad freight structure n-ill reveal several funda- nrental rrcil. Because of tl~c relatively high iwst (~f t,ransferring rlripments fronr me railroad tu another, it is desirable tr~ locate plants along major railrmtd ruutes so tl~t sl~i~~u~~nts will follo\v the major

Plant Location 1 lines betn-ccn the shipping point and ultiinatc destination. TVhere pos- sihlc it is desirable to have more than one railrond servicing a com-

~i~unity because of thc greater flexibility snch service providw. JInny larger communities served by several railroads have terulinal companies or so-callctl belt-line railroa~ls nhicli are often jointly orwed by the several railroads in the region. Thebe trrminal railroad; provide service hetveen the tracks of the major railroads entering the com- n~unity and all plant sites. Such service is rapid and proiluces cheaper transfer from road to road and ultin~ately to tllc pltrnt. Area< served by terminal companies, therefore, are to be derirwl.

If large amounts of LCL ehipmcnk are anticipitfd, the esistmce of a car-loading company in the area is advantagrou.;, These car loaders offer door-to-duor LCL service. They collrrt a nulnhcr of LCL shipments from an area having the same (lfhnation, and are able to assemble complete carload shipments for delivery to the r:iiIroad Some railroads provide similar service in large communities.

At first tl~mght it may seem that a plant should either be located at the raw n~aterial source or at the market for its ~irocluctr. Consider- ing t,ranq~ortatioa ali~nc, horrever, an intermediate location may he just as advantageous. Railroads offer fahrii.ation-in-trw~lsit privileg~.~ for certain commorlities. This privilcgc pcrmits the material to be shipped to a plant. processed, and then sent on its vny t(~ tlrc ultilnate destination for essentially the same rate that ~~-ould hare been clrargcd for a non-stop trip. It is n.ell to check the existence of such pririlegcs for the comniodities to be produced. Many other rate pcculiarities lravc cvi~lved as the railroads dc\~lopcd and conil1etition became keen.


Interstate truck n~overnents, as in the case of the interstate railroad transportation, are now regulated by the Interstate Commcrcc Com- mission. Truck lines are elasscd as schctlulcd or non-scheduled car- riers, depending upon xhether the line offers a regularly scheduled service betwen tvo points or operates on a contract basis at timcs convenient to the shipper. Truck lines have been able to compete vigorously with tlrc milroads on small shipments and in particular on short hauls. Because of the competitive advantage in this phase of freight shipment, the truck lines have concentrated on the development of efficient means of handling less-than-truck-load-lots (LTI,). As with railroad freight, excessive transfer should be avoided. Location of a plant on the route of a major carrier providing direct connections to various shipping points eliminates the need for transfer and cuts costs.

In considering truck transportation in a given community. the fran-

12 Project Engineering of Process Plants

Water Transportation

\v;ltT tr:ili,~l~nrtntion i. ni it pol :l!Y:iy. hc tilt, r~lvl~~l~st

IC:I I ti~~c~rtti~, :I I I I of get I~. It is certainly an a,iv;rnt;~ge for n prow-s phnt to 11c I~uateII :~dji~(,~nt to n:iaigal)l~~ at c,vcn thnugli initial oper:rtions do not require n-atcr sllipmenrs. \Inn? co~npiinics 1:lre becn :ihlr to ctirnprtc~ rlfectivi~ly in (Iist:~nt 111xrkc,t- eren tl~ou!J~ these I:I~~I?S nrcx ~er~~~l 11y p1~11ts in tht>

~ilarket nrw .\ (':~lifornia ~~ro~tuccr ill an~n~mia I,:I~ slri]) li~lui(l :I)I~~:I in ?e:i-g~i~rg 1,arge.s to the P;rrifiv S~rtl~\vest iin~l cuuil~t'te \\-it11 plants 1oc:iterl in tlic J'acifir Sorth\\-cbt rerrit,~ry. :\ hrge Gulf C'oa.4 rawtic 11ro~ln(w >hips 735 caustic by XI-going tarrk~r to cad roast tcr~i~i:ils fro111 ~11en1:c it is Sc~rwiril~~~l 11y rtiil md tniuk to east coast u:ers. Here ~igain lor cwt water frc4gllt enables tlic pro~luiw to cunq~etr 1~it11 ~ir~dwt~rs in the ~i:~rkct arc^

In irilditim to occ:i~~ tra11sp~rtiitim1, tllc Cnit~d Stzit?> is fi~v~red wit11 many ~niles oi navigable strea~ns and canal.;. Pcrllnps tile most ?pc- taclllar c:ilial systcn~ is tlic Intercoastal Canal \vl~irh I~IIX-itlei pre~tcrte,l shipping I:ine.. for barge traffic iron1 Bra\\-nsrillc, Tcms to Sew Eng- land. Tlle Grc;it I.akcr am1 large rivers sue11 as the ~li~i~sip~~i. ()trio, Hu11sti11. am1 'L'rnncrsc~ llrovirle adiliti~~r~nl tlroos;~nds of milei 1 navi- gabk n.;it~.n\-:i>-s ~nis>iug througli tl~e l>ol~ui:~tiou centrr- the 1-nit~vl Sti~tes.

I 1vorcs~ 11lants Irave iound it ;~~l\-auingcwus to ojrerate their

OI-I .sIrip ;ir~d b:l~jir.<. :1ltlroug11 tllc. .wvicc.- of .Aipping coll~l~;~nit.; art, Y~I:I. Ti, *tin~lrl:ite I\-iiter tr:~nb]~orti~tion the iwlwil gover11- ~iient I:I~ iur :i rrunlber oi years ol~erate(l R large barge linv rallcil The Fw11,r:iI Ihrgt, 1.i1iw

Other Means of Transportation

Tllc, wrvirvs offcwcl 11y tl~c :tir linvs, expwss co~npariiw, the I'wt

Ofliw Ik.part111e11t~ aid pipt,Iincs vnry in illq~ortance (lcpen~ling upon the psrti~wlar plant in question. Heenare of tl~e increa~e in airlinr trnffic and the trli~j~o of present day industry, it is a~lvantngcuus to he 111rated conveniently to an aiqlort if for no ot111~ renron th~n fur tllc convenience of company prrsontiel trtivrling ou plant hu.;ilicss. Although ieiv process plants n-ill require eontir~uous air freight ship- nwnt, it is IIO~ uncommon to call for an emergency air sliipliient oi

;>uts for plnni cquipn~ent. Here again tlic eonvenimt location of an alr111)rt is :in adrantagc.

Plant Location 13

Process Water The ~~OCCS~ i~i~lu-tric~ rank :~l)o~-e :ill uthcr. :I- users oi n-a(i,r. 1-1 process plant cuuld operate \vithout rratcr 35 a rooling medium and :IS ;I direct r:ix material in certain ]~l~ascs irf :I process. The n.att.r i~~pl'ly of an area, ~IIIW~OYC. I-t 1: stuili~1 IJ~EOTC that area 1,:1i eveii IIC? runsidered as a pussil~le rite. .id\-icc rhould be sought from competmt iv:itcr experts, inrlwling grologists iincl cl~crnir~al rrgini'r.~ ;~~r~r~i:iliziirx in n-ater prol~lcuis. Prior to the study, a clutaileil estimwtr of water rrquirclncnts 110th for tile i~rescnt an11 the fntwe luust 11c ~uacle. Thi? ~IIIUIII t11c,1i i'ollon-etl by wrcful study of the v-atcr availal~lr in the rt,gion heinlr t~unsidcrccl. IS well n-ater is to I, used a. twmplrtc stud? of tlie I;I..(. Iliatory of the underground \v:iter table is necessary. Because oi their lo~er temperature, undergri~u~id water supplies arc prefcrrrd if :i~lcqoatt,. Powell and Yon I~ssbcrg" Ilave clescril~e~l n ~netliod ior predictilig tire Suture a~ailatlility and rrlial~ility of utidergror~~ld \I--;ltt.r bupl~ly hy tpsting existing ivell.!. IYater lrvrls in obsrrvatiim n-clls are ~rleasurc<l during tlie pumping of nr:lrl~y active n-rlls. The iur~luilx uf Tl~ei+fJ is thcn ustvl to prcrlict t11c il~~:in-clon-i~ iinticipatui or-er :I long period r~f p~~rnpi~ig. RI~~:I~I, n.;itcrs frim~ S~~~:IIIIS rlr I;tl<cs also reqriirc r:1wf111 t,o~~si~ler;t- t,ion si~~eo tllcy arc often :~ffected scvcrcly I irason;d variations. Fresh water streams discharging into the wean during tinies of low run-off can becoll~e salty due to sea lvater 1;leli-up. Under these ~:miditions, it may he necessary f(ir the plant to provide large stor:igc facilities for fresh water to be collected duriug the period of liigli run-off and useil during the season \illen the strcilm brco111es salty. It i necm-iuy to clri~rk :Ire 1listw.y of I.~TL.I. flon. ~IY Iik~ l<.sel for :I> irit~~iy years 1;1rlc us pwsil~lt: so that :i.surnncr oi :11 ndc~~uate ..1ily

(Parte 2 de 10)