LIQUID INTERFACE LEVEL MEASUREMENT - …

1 SpecialApplicationSeriesLIQUIDINTERFACEL EVELMEASUREMENTTheEmul si onLay erheneed for int erf ace me asu rement ar iseswhe nev er immisc ibl eliqu ids tho se incapableof mixi ng re side within the same eligh ter mater ial rises to the topand the heaviermat erial settl es at the bo ttom. Inoil produ ction,forexample ,water or ste am isused to extract oilfro mawell .Wel lfluids then rou te to product ionseparat ors whe re they settl einto the ir primaryconst ituent parts as awa ter- hydr ocar bon inter er may also beuse dasatranspo rt mediu moracle aning age nt and forms an inter face wit hanalli ed mate rial wh ich islat er ext racte rfac es are most commonl yfound in thedi verse separatio nprocesses that are essent ial toeveryind us try. Sep arat ion reco vers ad di tives, cata -lyst sor solve nts, ext ract simp urit ies, and rou tesme dia into di ffe rent pro cessi ng cha nne ug hour emph asi sis onliquid /liqu id inte r-face,int erface salso form betw een liqui dand solids,liqui dand foam, or LIQUID and aga s s uc has gase s(ot her than ai r) that are us ed intank blanket cible LIQUID smee talong an inter face lay erwhe re they und ergo some amou nt of emu lsif ica -tion.

2 Th is emul sio nlayer (al so cal ledaraglay er)may for manar row and precise bo unda ry; bu tmo re freque ntly it isabro ade rgradi ent ofmixe dliqui ds o rliqui ds mix ed wit hpa rtic lesthat formaslu rry. Ge ne rally, the thick er the emuls ion layer,the great er wi ll be the me asu rement challe wing theposit ion ofapro cess inte rfa ceisne cessar yfor mainta ining pro du ct qu ality andop erati ons effi ciency .The inte rfa ce is mea sure dand cont rolle dby precisio nlevel switch es andtrans mit ter s. Though at least 20dif ferent types ofliqui dlev el measur eme nt devices are in servicetod ay, only avery few are suita ble foraccu rat eandreliable inte rfac emeas ureme fivelead ing int erf ace me asu rement tech -nol og iesinuse today are discu ssed in thepagesah ead. Gr oupe dby their ope rat ing tec hnologies,the se inc lude Buo yancy (Fl oats and Displ acers),RF Cap aci tanc e, Ther mal Disper sio n, Rada r, andRed und ant Technolo gie s(tho se comb ining twome asur ement techno log ies in one instr ument ).

3 Pet roleu m and Gas Separators LP G Dehydrators Heat er Treat ers CrudeDesalters Free-wat er Kno ck-o ut Regenerators Coalescers CrudeDewatering Acid SettlingTanks AlkylationTan ks CokingDru msWat er & Was te water Settlement Tanks Clarifiers SludgeTh ickeners FiltrationSystems FinalEfflu ent MonitoringTThe Needfor Interf aceMea su reme ntInt erfa ceMea su reme ntTe chno logyOt her Ind ust rial Liq uid OxygenandNitrogen pr oduction DigesterVessels Ex tractors& Separators GreaseTraps Pulp and Pap er Miningand Quarrying Foodan d Beverage Bio Phar maceutical Chemical Plants StorageFacilitiesPr inci pa l Applic atio nsLiquid/LiquidInterface The LIQUID / LIQUID INTERFACE including classic oil/waterproducts is found in separa-tion, purification, catalysis,extraction and other These interfaces are commonin Water and WastewaterTreatment, Pulp and Paper,Mining and Quarrying, andChemical INTERFACE detection betweenimmiscible fluids can becalibrated in some controls toalarm when the LIQUID changesto The phase change of avaporto aliquid is detected instorage tanks, tank cars andprocess systems.

4 Interfacesbetween vapor and foam canalso be pes of Inter fac e 2 INTERFACE101 The Tu ffy side-mo unt ,float-type switch is compactand econ om ica l. Asimple and reli able T20 top-mo un tswitch. One of Ma gnet rol smany float ordi splac er, external cage swi tches . Di splacem ent -typecont rols are well-su ited for simple or complex interfa ceappli cat ions. ModulevelMEASUREMENTPRINCIPLE:Aflo at calibra ted for interfa ceser vice must be he avy enou gh topen etrate the upper LIQUID yetbuoy ant enou gh to flo at on thelow er liqu :Max Pres sur e:300 0psi g@+69 7 FMin Pr ess ure :Full Vacu umMax Tem pera tu re :+12 00 FMin Tem pe ra tu re :-150 FSens it ivi tie is themini -mum difference allow ablebe tween the of the uppe ran dlower liqu dif fer -ence approa ches this limit, verylar ge float sare required.

5 INSTRUMENTOPTIONS:Float -type swi tches available fortop,side mo unt ing, and externalcage applicat ions .Awid erangeof me rcury, dry con tact, herme t-icall ysealed, pn eumatic andvibr at ion-res istant switch mech -an ism sare offered .DisplacerSwitchesMEASUREMENTPRINCIPLE:I nt erf ace lev el mo vement changesthe buoyancy force on adis placersuspended from arange force change on the springcauses it toextend or com pres s,mov ingan at tract ionsleev eint oorout of the field ofthe swit chmagnet ,act uat ing the :Max Pressure:50 00 psi g@+300 FMin Pressure:Fu ll Vacuu mMax Temperatu re:+50 0 F@2665 psigMin Temperatu re :-150 FSensitivities:Wi der deadba ndsthan flo at ;ent ire displa cer mustbesub merged ininterface serv :Top-m ount ing displa cer switchopt ions includ eelectric or pneu -mat icswitch mechanis ms andenclosu res; Proof-er gro undcheck; and awi de range of con-nect :Move men tofthe inte rface lev el alo ng the lengt hof thedispla cer causes the precision range sprin gto extend orcompress.

6 Th is caus es the move men tof thecore within alin ear variable diff erentialtran sformer in the electronic Modu leve l result ingin adi gi talorana log outpu t. In the Pne umaticModulev el, this causes themo vement of amagneticball whi chgu ides the magnet carriage res ulting inapn eum at ic out put :Th is techno logy is wide ly use dfor INTERFACE servicebec au se it is una ffected by emu lsions and will accu -rate ly track the middle of the emuls (ElectronicModels):Ste am Applica tions: 2 0 Fto +500 FNo n-S te am App lic ations: 2 0 Fto +600 F(wi thcar bon steel chambers)Proc ess Pre ssu re :Up to 5100 psig @+100 FFar Left:Sho wn withcut aw ay view storev ealthe po sitionof itsrangespri ng and displa cer,Pneum at icMod ulev elcont rollers offer highreli ab ilityin tempera -ture and pressureextrem :E3 Mo du lev elelect roni ctransm ittersoffer advanced int erfa cecont rol indigit al orana -log versi ons.

7 DisplacerControllers&TransmittersFloatSw itches3 FLOAT&DISPLACERI N T E R FA C E T E C H N O L O G YRF TE CHNOLOGY:KOTRON RF(Rad io Freq uency)Capac itance-t ype electronic controls offerman yint erfa ce me asurement adv an tages: Up to150 -foot mea surement range Con du ctiv eand non -cond uctiv eliquids Corr osive and ab ras ive media res istance Exten sive sens orprob eselectio n Nomov ing part s Maintena nce free!RF MEA SURE MENTPRINCIPLE:Asmed iarise and fall inside atank, theamou nt of capa cit ance develo ped betweenthe sensing prob eand the ground referencerise sand falls .InRFswitches, this cha ngeis sen sedby the electron ics and con vertedinto arela yope ratio n. In RF tran smitters,the elec tronics con vert the capacitancechan ge into acon tinuous leve lmea INTE RF ACE MEASUREME NT:Th ediele ctric con sta nt ( )of the pro cessmedi umis crit ica lly importan t.

8 The higherthe di fferen ce betwee nthe dielectric con -stan ts of the pro cess ma terial and the area ofthe twolayers the easier the interfa ce me as -ur emen twill PROCESS CAPABILITIES:Max Pre ssu re :2000 ps ig @+100 FMin Pre ssu re:Full VacuumMax Tem pe rat ure:+40 0 F@200psigMin Te mp er at ur e:-40 F@3000 ps igSens it ivi tie s:Va riable dielectrics andcon du ctiv ecoa SWITCHOPT IONS: Single-po intand multi-point Integra lorrem ote location Field sele ctive fail-safe setting Intrins ica lly saf eprobe circu itry Narr owor wid edif ferentia l Eas ycalibra tio nmodelsRF TRA NSM ITT ER OPT IONS: 4- 20mA, 20 -4 mA output Integra lorrem ote location Self di agnos tics FMan dCS Aapprov als Up tofour cont rol rela ys LC Ddispla yan dkeypad optio ns Tw o-w ire, 24 VDC,loop-pow ered RS -485 Modb us com municat ion HA RT di gi tal com munica tio n Dual cha nnel operation for two pro besSwitches: Inthe oi land wat erinterf ace ab ov e, RFPoint Switchespro videins tant aneous detectionof the di ele ctricdifferencebet ween the twomedia.

9 TheModel 822 Mult i-Point Switch canuse on euni tfor pump Mo del 80 4provides pu mpcont rol and 4-2 0mA output. Transmitter: ACapaci tance trans mit terwi ll measure tot al vessel capacita wat er has ahigh dielectric, mos tcapaci tance isgenerated by the wat er. The di elect ric( )in the raglayer (redbo x) changes from to 80. As wat ermi xed inthe oi lincreases condu ctivity,theemulsi on layer will appear tobe morelike wat er than oi ONPU MP OFFWATER OU TAIR : =1 OIL: = TE R: =80 Emuls ion: =?805082801804 Transmitters822832842811 SwitchesI N T E R FA C E T E C H N O L O G YRFCAPACITANCE4TD TECHNOLOGY:THERMATEL switche soff er anew leve lof inter face perf orman ce and reliability intherm aldispers ion technology (see produ ct-spe cific feat uresin grey box below right): Accurate, fast-respo nding technolo gy Ea sy, quick cali bration No taffect ed bytempe rature, press ureor viscosity.

10 Nomov ingpa rts M ainte nance free!TD MEAS UR EMENTPRINCIPLE:Sw itches us ing thermal dis persion tec hnolo -gy det ecthe at tra nsf er which red uces the tem -pe rat ur edifference betw een the switch stwosenso rs;onesen soris for referen ce and theoth er is hea tedto atemperature above thepr oc ess tempera ture. The temperature dif fer -enc eisgrea tes tin air, then decreas es whencool ingoccurs due to achange in media. Theelec troni cs com pare the electrical sign al fromthesens or agains tthe set point and provide arelay actuation .TD INT ER FA CE ME ASUREMENT:The Therm atel TD1/ TD2 and TG1 switc heshave be en de signed an dengineered for leve l,flow orint erfa ce detection. When used asaninter fac edete ction switch, the set po intcanbe adj us ted tode tect thedifferen ce in mediabe twee ntwofluid stha tha ve different thermalcond uc tivity.