Sirous Zamanirad 1, Said Mazaheri 2, Mehrdad Ghafourian 1

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1 INERNAIONAL JOURNAL OF COASAL & OFFSHORE ENGINEERING IJCOE Vl.1/N. 2/Summer 2017 (21-26) Avalable nlne at: Intrducng a Methd fr Mre Precse Predctn f Berth Occupancy Rat n Bulk Lqud ermnals Srus Zamanrad 1, Sad Mazaher 2, Mehrdad Ghafuran 1 1 BEhn arhe Apadana Engneerng and Management Grup (arh-e Nw Andshan Hldng) 2* Crrespndng authr: A/Prf. f Offshre Engneerng, Iranan Natnal Insttute fr Oceangraphy and Atmspherc Scence; sad.mazaher@gmal.cm ARICLE INFO Artcle Hstry: Receved: 28 Jun Accepted: 26 Aug Keywrds: Berth ccupancy rat Prt plannng Prt master plan Bulk lqud termnal Prt perfrmance ptmzatn ABSRAC 1. Intrductn Occupancy rat plays an mprtant rle n prt plannng and prt master plan desgn. he number f berths shuld be establshed based n peratnal requrements, drven prmarly by berth ccupancy cnsderatns. he ptmum berth ccupancy depends n thrughput requrements and ste cnstrants. he assessment f the berth ccupancy s based n the cnsderatn f vessel arrval and departure tmes, tme at berth r vessel turnarund tme, dwntme caused by mantenance, and severe envrnmental cndtns (stppng f ladng and/r vessel leavng the berth) (1). Vessel turnarund tme s the duratn f vessel s stay aflat alngsde berth and als vewed as prt s peratnal ndcatr fr ts ptmum perfrmance n term f the capablty, effcency, and prductvty f peratn prcesses f petrleum termnal n handlng nbund and utbund carges va publc lqud-bulk jettes (2). Estmatn f vessel (r cntaner grup per shp) turnarund tme durng the cnsdered tme perd depends n the acceptable average watng tme t average servce tme rat. hs parameter s btaned as the functn f berth ccupancy, number f berths, number f cntaners, watng and servce tmes and berthng and unberthng tmes (3). Exstng methds presented n references and standards fr calculatn f berth ccupancy rat, are mre cncentrated n cntaner termnals. Hwever, sme emprcal frmulas can be fund t predct the berth ccupancy, but these methds are nether accurate enugh nr ecnmcally wse t be emplyed fr the predctn f berth ccupancy rat n large and cmplex bulk lqud termnals. herefre, t s attempted n ths paper t ntrduce a methd fr mre precse predctn f berth ccupancy rat fr bulk lqud termnals. In the prpsed methd fr calculatn f berth ccupancy rat n bulk lqud termnals, tmes whch s nt used fr ladng/unladng peratn s nvestgated. he ladng/unladng lst factr s cnsdered n calculatns n rder t calculate the peratnal value fr ladng/unladng rate. Next, practcal values fr these tems are gven based n prevus authrs experences. Fnally, a case study s perfrmed fr a lqud bulk petrchemcal termnal t specfy the presented methd. Results shw 24% dfference between new methd and ld emprcal frmulas. Varus methds and appraches are presented n references and standards fr defntn f berth ccupancy rat. Fr example, ths rat s presented n PIANC manly n term f yearly wrkng tmes that results an average value f ccupancy rat n a year (4). Carl A. hresen, 2003 (5) defnes ths rat n term f weekly wrkng and servce hurs whch may results varus values fr seasns and every mnth n a year. In addtn t desgn stage and prt plannng, ccupancy rat s used t evaluate n servce prt perfrmance n rder t plannng and perfrmance ptmzatn purpse. Berth ccupancy studes help the desgners t plan a termnal n ptmum thrughput, traffc cndtn and shp watng tme. Lw value f berth ccupancy rat s nt acceptable t the prt authrty frm ecnmcally pnt f vew, whle the hgh value lead t traffc cngestn and ncrease f shp watng tme. he ptmum range f (4) and (6) percent are gven n terms f number f berth and carg type (cntaner, bulk and lqud bulk) n the related standards. Generally, berth ccupancy rat shws the prt servce level whch can be defned as bellw: 21

2 Vessel departure unberthng end f ladng/unladng start f ladng/unladng all made fast n berth leavng harbur vessel arrval t harbur Srus Zamanrad et. Al. / Intrducng a Methd fr Mre Precse Predctn f Berth Occupancy Rat n Bulk Lqud ermnals Pre- berth tmes watng and nspectn(f requred) navgatn and berthng pre-ladng/ unladng affars Fgure 1- Break dwn f shp s tmes n prt span are dfferent fr varus termnals (cntaner, BOR 100 (1) bulk, general carg) and may vary due t prt t perfrmance, the presented structure n Fgure 1 s BOR Berth Occupancy Rat n percent fxed. tal tme whch quay wall s ccuped frm berthng t un-berthng (vessel turnarund tme) n hur n the prpsed tme span Calculatn f ttal tme whch quay walls t tal tme whch quay wall s able t servce n are ccuped ( ) hur n the prpsed tme span (wrkng tmes) In case f nvestgatn f berth ccupancy rat n he value f 365 wrkng days n a year and 24 actual peratnal cndtn (prevus prt wrkng hurs n a day are cmmn n calculatn f perfrmance), may be calculated based n yearly wrkng tmes f mdern termnals. hs value may be reduced fr termnals wth lw traffc. Hwever calculatn f ttal tme whch quays are able t servce n hur n year ( t ) desn t need cmplcated calculatns, many tems affect calculatn f ttal tme whch quay walls are ccuped ( ) and needs varus cnsderatns n case f prt type and perfrmance. tal tmes f a shp n a prt frm arrvng t leavng tme culd be dvded t three man tme span: preberth, at berth and after berth tmes whch are presented n Fgure 1. Pre berth tmes are related t vessel watng tmes, nspectn (manly fr bulk carg shps) and vessel navgatn frm harbr t berth and berthng peratn tmes. At berth tmes ( n Equatn 1) are manly related t ladng/unladng peratn. he affars related t meetngs, dcumentatn and nspectns have fewer shares n ths tme span whch are gruped as pre and after ladng affars. Fnally, after berth tmes whch are related t vessel navgatn frm berth t sea. Hwever, the detals f each tme 1 One week, mnth r year whch s selected based n prt traffc and avalable data. Fr prts wth very hgh traffc, perd f ne week s adequate. In present paper, the tmespan f a year was cnsdered fr calculatns. me at berth r vessel turnarund tme ladng/unladng peratn and tests(f requred) (me) 22 regstered tmes n shps statement f fact dcuments fr the prpsed tmespan whch s calculated as belw fr each berth separately: after ladng/ unladng affars n 0 Unberthed Allmadefast ) 1 After berth tmes navgatn ( (2) he regstered tme n shp s statement f Unberthed fact d cuments that shp s unberthed frm the quay (hur). he regstered tme n shp s statement f Allmadefast fact dcuments that berthng wrks are fnshed and shp s ready fr nspectn and ladng/unladng (hur). tal number f shp whch s berthed n the prpsed berth fr the prpsed tme span. In case f nvestgatng berth ccupancy rat fr prt plannng, he rat f prt yearly thrughput t prt ladng/unladng capacty results an estmate fr (equatn 3). (3) P A.. Berth annual planned thrughput n EU r tn per year

3 Srus Zamanrad et. Al. / IJCOE, 2017, 1(2); p P he berth s equpment prductvty n tn r EU per hur Fr mre exact calculatn f, varus parameters whch affect ladng/unladng peratn shuld be appled t equatn 3. mes f berthng whch s nt used fr ladng/unladng peratn lke dcumentatns and clearance, nspectns and meetngs are neglected n ths methd. In the fllwng, s nvestgated n tw parts. Frst, tmes fr ladng/unladng peratn and secnd, tmes fr tank nspectn and samplng, dcumentatn and clearance. As perfrmance system and tmng are dfferent fr cntaner, dry bulk and bulk lqud termnals, calculatn f s presented fr each termnal separately Cntaner ermnals he nvestgatn f cntaner termnals n respect t BOR s cmpletely dfferent wth ther termnals and manly affected by prductvty f each meter f quay wall length, whch s estmated by crane densty n quay wall and crane prductvty. hese numbers vary n term f berth desgn vessel and ladng/unladng equpment. he average value f crane densty s ne crane per 100 m f quay wall and n mdern cntaner termnals s abut ne crane per 75 m. he crane prductvty vares frm 10 lft/hur fr mble harbr cranes t 30 lft/hur fr mdern shp t shre gantry cranes (4). S, n cntaner termnals can be calculated as presented n belw equatn: N s ther (4) N c PB feu A.. ermnal annual planned thrughput n EU per year Number f crane n termnal r berth Nc P C he berth s crane prductvty n lft/hur f he rat f 20 ft. cntaners cmpared t 40 EU ft. cntaners (EU/Bx), whch may be cnsdered abut 1.5. tal number f shp n a berth fr year. N s mes whch are related t nspectns, ther dcumentatn and clearance n hur whch shuld be calculated based n prt perfrmance Dry Bulk ermnals As carg type and ladng/unladng capacty f equpment may vary n each berth f a bulk termnal (lqud/dry), the ccupancy rat calculatn fr these prts shuld be nvestgated fr each berth r berths wth the same carg type and ladng/unladng equpment separately. S, the relatn fr s gven as belw n term f annual thrughput and number f shp n year: 23 N s ther (5) PB A.. Berth annual thrughput n tn per year P he berth s equpment prductvty n B tn/hur tal number f shp n a berth fr year. N s mes whch are related t hld nspectn, ther draft survey and dcumentatn and clearance whch shuld be calculated based n prt perfrmance. Rat f the carg(s) annual thrughput t desgn vessel capacty results ttal number f shp fr berth n a year. Fr mre exact results, an average sze fr vessels r even prpsed carg parcel sze s used nstead f desgn vessel capacty. In sme cases, there are tw r mre carg ladng/unladng equpment n ne berth whch may be fr the same r varus carg types. In case f same carg, the ttal value f equpment prductvty shuld be used n equatn 5 and In case f varus carg types, shuld be nvestgated fr each carg separately and the sum f calculated tmes are used fr calculatn f ccupancy rat. S fr the secnd case, equatn 5 can be wrte as bellw: m ( Ns ther ) (6) 1 PB A.., P B, N s, Reefer t equatn 5 ther Number f carg types n ne berth 2.3. Bulk Lqud ermnals he frmula fr bulk lqud termnals s lke dry bulk termnals but prduct densty and ladng/unladng lst factr shuld be cnsdered n calculatns. S, the equatn 5 s rewrtten as belw: NSther (7) PB fl A.. Berth annual thrughput n tn per year P he berth s equpment prductvty r B nmnal pumpng rate n cubc meter/hur whch s gven fr ladng arm r hse Prduct densty n tn/cubc meter Ladng/unladng lst factr f L N s tal number f shp n a berth fr year. mes whch are related t hld nspectn, ther draft survey and dcumentatn and clearance n hur whch shuld be calculated based n prt perfrmance. In bulk lqud termnals the peratnal value fr berth s equpment prductvty s nt the same

4 Srus Zamanrad et. Al. / Intrducng a Methd fr Mre Precse Predctn f Berth Occupancy Rat n Bulk Lqud ermnals nmnal values manly due t prduct evapratn (fr lqud gas prducts), pump perfrmance and due t lne blwng after ladng cmpletn. S, the ladng/unladng lst factr s appled here fr mre exact results. he belw equatn s gven t calculate lst factr fr each prduct r prduct wth the same specfcatn: q P. S. ( ) 1 PB L / U (8) f L q f L, P B, Reefer t equatn 7 P.S. Carg parcel sze n tn whch was laded/unladed L / Practcal tme fr ladng/unladng U tme based n prt perfrmance (shps statement f fact dcument) Number f nvestgated peratns fr ne prduct he value f lst factr s varus fr lqud and gas prducts and ever may changes fr varus prducts by densty. Prduct handlng n bulk lqud termnal wth hgh value f annual thrughput lke l termnals s perfrmed by mre than ne ladng arm r hse. In ths case, the ttal value f equpment prductvty ( P B ) shuld be used n equatn 7. As each berth n refned r whte prducts (Petrchemcals) perfrmed ladng/unladng f varus prducts, calculatn f shuld be perfrmed fr each prduct separately as presented n equatn 9. m ( Ns ther ) P f 1 B L A.., P B, f L, Reefer t equatn 7 (9), N s, ther Number f carg types n ne berth Cnsderng all parameters fr calculatn f n bulk lqud termnals, equatn 10 s gven fr calculatn f berth ccupancy rat n bulk lqud termnals. m ( Ns ther ) 1 PB f L BOR 100 t (10) BOR Reefer t equatn 1 A.., P B, f L,, N s, ther Reefer t equatn 7 Reefer t equatn 9 Parameters lke ladng/unladng lst factr and tmes whch are nt usable fr ladng/unladng peratn have been appled n equatn 3 t reach mre exact results fr. It s clear that berth ccupancy rat s generally affected by berth s equpment prductvty and termnal wrkng hurs, but the presented parameters may change the result cnsderably. clarfy the dfference f results fr each methd, In the next sectn a case study s perfrmed fr calculatn f berth ccupancy rat n a bulk lqud petrchemcal termnal. 3. Case Study-Occupancy Rat n a Bulk lqud termnal In ths sectn, a case study has been perfrmed n ne berth f a petrchemcal termnal. he prpsed berth perfrms ladng/unladng f 9 prduct wth 8 ladng/unladng equpment as shwn n Fgure 2. Fgure 2-Berth Prduct Blck Dagram 24

5 Srus Zamanrad et. Al. / IJCOE, 2017, 1(2); p Yearly rghput (tn/year) Parcel Sze (tn) Fgure 3.he prt perfrmance prcess dagram (exprt peratn) Number f Shp n Year Befre nvestgatn f berth ccupancy rat n a termnal, t s necessary t analyze shp s tmes n the prt frm arrvng t leavng. Detals f these tmes are presented n Fgure 1, shuld be specfed fr the prpsed nvestgated prt. It culd be mre applcable f the breakdwn be studed alng wth prt perfrmance prcess dagram. he prt perfrmance prcess dagram fr the prpsed prt s presented n Fgure 3. Prt perfrmance prcess dagram drectly affects berth ccupancy rat and shall be analyzed befre berth ccupancy rat calculatn. In sme cases, ptmzatn n ths dagram may reduce berth ccupancy rat. Fr example, n sme bulk lqud termnals, pre-ladng tank nspectns are perfrmed n berth whch ncreases shp s tmes at berth and berth ccupancy rat. But n the nvestgated prt these tests are perfrmed n harbr (pre-berth tmes) able 1. Lst f prducts and ccupancy rat calculatns Ladng/Unladng Equpment Nmnal Pumpng Rate (cbm/hur) 25 that reduces shp s tmes at berth and berth ccupancy rat. Parts whch are related t shp s at berth tmes are separated n he prt perfrmance prcess dagram (Fgure 3). he yearly thrughput f each prduct s shwn n the able 1. he ttal berth thrughput s mlln tn per year. he number f shps n a year are calculated frm dvsn f yearly thrughput t average carg parcel szes fr each prduct separately. Cnsderng prt perfrmance prcess dagram and shp s tme breakdwn, he value f 3 hur 2 s calculated fr ther (equatn 7). he next-t-last clumn s ttal tme whch quay walls are ccuped ( based n equatn 9). he average value f 70% s Pumpng me n Hurs by Equatn 3 540,000 15, Ladng Arm % , ,000 12, Ladng Arm % , ,000 10, % , Ladng Arm 220,000 10, % ,000 10, Ladng Arm % , ,000 8, Hse % ,000 8, Ladng Arm % ,000 15,000 4 Hse % ,000 10,000 4 Hse % ,168,000.0 tal 5,838 3,763 f L ther Occupancy Rat 8,760 8,760 67% 43% 2 As mentned n sectn 3.2 the value fr ths parameter shuld be nvestgated fr the prpsed termnal. he value between 2-4 hur s cmmn n practcal. t

6 Srus Zamanrad et. Al. / Intrducng a Methd fr Mre Precse Predctn f Berth Occupancy Rat n Bulk Lqud ermnals cnsdered fr ladng/unladng lst factr n the nvestgated berth. As gven n the last rw f table 1, the berth was ccuped fr 5,838 hurs n a year. Cnsderng 365 wrkng days n a year and 24 wrkng hurs n a day, s 8760 hurs fr ths berth t (fr a year). S, the ccupancy rat fr the berth s 67% based n equatn 1. In the last clumn ttal tme whch quay walls are ccuped ( ) was gven wth the general equatn fr calculatn f ths number (equatn 3) and the value f 43% was calculated fr ccupancy rat whch has abut 24% dfference wth the new prpsed methd. 4. Cnclusn Calculatn f berth ccupancy rat are nvestgated fr cntaner, dry bulk and bulk lqud termnals n present study. Cnsderng varus parameter n bulk lqud termnals, a methd fr mre precse predctn f berth ccupancy rat has been ntrduced fr these termnals. Hwever, berth ccupancy rat s generally affected by berth s equpment prductvty and termnal wrkng hurs, ther factrs lke ladng/unladng lst factr and tmes whch are nt usable fr ladng/unladng shuld be cnsdered n bulk lqud termnals. Fnally, t clarfy the prpsed methd, a case study was perfrmed n a bulk lqud termnal. he mpact f 24% was bserved fr cnsderng f ladng/unladng lst factr and tmes whch are nt usable fr ladng/unladng n calculatn f berth ccupancy rat fr the termnal. 5. References 1. Recmmendatns fr the desgn and assessment f marne l and petrchemcal termnals. Bruxelles : he Wrld Asscatn fr Waterbrne ransprt Infrastructure, Reprt n Petrleum termnal s peratn prcesses n vessel turnarund tme. Shah, Ng Sew Mng and Muhammad Zaly Berth ccupancy at cntaner termnals: cmparsn f analytcal and emprcal results. ZORAN RADMILOVIC, SASAJOVANOVIC. s.l. : Prmet-raffc&ransprtatn, 2006, Vl Master plans fr the develpment f exstng prts, REPOR N 158. Bruxelles : PIANC-he Wrld Asscatn fr Waterbrne ransprt Infrastructure, hrsen, Carl A. Prt Desgner s Handbk: Recmmendatn and Gudelne. Lndn : hmas elfrd, Prt develpment, A handbk fr planner n develpng cuntres. New Yrk : Unted natns,

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