In-lineBlendingSystems In-

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In-line BlendingIn-line Blending is thecontrolled, continuous mixing of a number ofcomponents to produce afinished product of closelydefined quality.

The quality of the product iscontrolled as it is made.This is invaluable incontinuous process industriesbecause the final product canbe blended, analysed andloaded in a single process.

The alternativeBatch blending is the mainalternative. It involvessequentially introducingmeasured volumes of eachcomponent into a tank.Thecomponents are then mixed,analysed for quality and anyadjustments made to theblend.This is time consumingand makes it necessary tostore both pre-blended andfinished products.Nevertheless, for smallvolumes and certainapplications, this remains costeffective.

The specialistsJiskoot is an internationallyacknowledged leader in thefield of blending systems withover 40 years’ experience inthe design, manufacture andsupply of customised turnkeymeasurement systems.Jiskoot has supplied blendingsystems to many of theworld’s major oil companiesand has a reputation for

excellence and reliability. Ourdedicated engineering team isable to select the bestmeasurement and controlequipment and design,manufacture, install andcommission a turn-key

blending system with aperformance guarantee.

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Why

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In-line blending has manyadvantages over batchblending.

Improved qualityThe accuracy of an in-lineblending system is governedby the accuracy of theindividual componentmetering devices. Individualcomponent accuracy betterthan 0.25% over the fullmetering range can easily beachieved.

Faster blendingBy performing analysis andadjustment of the blend ratioon-line, the time consumingprocess of batch metering,tank mixing, product analysisand blend adjustment iseliminated. In-line blendinggreatly reduces process time,and provides a higherthroughput potential.

Greater flexibilityChanges in shipping schedulesand product specifications canbe accommodated simply byselecting a different recipefrom the controller. As theblender operates in real-time,configuring a new recipe is

quick and easy in comparisonwith the planning and stockmovement necessary withbatch blending.This allows youto offer a wide range ofproducts and can provide avaluable competitive edge.

Diesel forwarding system

Typical batch blending system

Componenttank farm

Mixing loop

Mixing loop

Blendtank 1

Blendtank 2

Blended product

Blended product

Crude oilblender

Reduced operating costCentralised control allows asingle operator to controlseveral blending operationssimultaneously. Once initiatedthe blender will automaticallyproduce the required finalproduct.

Reduced storage andcapital lock-upIn-line blending produces afinished product almostinstantaneously. It reduces theneed for complicatedproduction planning and thereis no need to hold stocks ofblended product. An in-lineblender can feed productsdirectly into road, rail orocean tankers for shipment.

Cost optimisationContinuous metering, closedloop control and higheraccuracy provides betterproduct dispersion, betterquality control and cansubstantially reduce the give-away of expensivecomponents and additives.Substantial savings can beachieved in plants with arelatively low annualthroughput.

Lube oil blender

Typical in-line blending systemComponent tank farm

Pumps

Meters

Control valves

Blend header

Blended product

Simplified plant layoutIn-line blending enables asimplified plant layout to beachieved. In existing plants thiscan free tanks, pumps andpipelines for other duties andin new plants can considerablyreduce capital costs.

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An in-line blending systemcomprises field equipment anda control system.

Field equipment The field equipment (valves,meters, analysers, etc.) enablesthe components to besimultaneously metered intothe ‘blend header’ to producethe final product. Productsnormally exit the blendheader through a mixer andcan be analysed to allowquality trim to be performed.In refineries, the componentscan be taken directly fromprocess units, avoiding orreducing intermediate storage.

Control systemThe control system monitorsthe outputs from the fieldequipment (flow rates, etc),performs calculations formeter linearisation,temperature compensation,etc. and feeds back theappropriate control signals tothe field equipment tomaintain the blending processwithin the requiredparameters (i.e. closed-loopcontrol).

Blending control systems useeither real-time or PLC(ladder logic) technology.Jiskoot supplies eithertechnology depending on

application. However, the cost,response times and controlprovided by PLC technologyhas a number of restrictionsand Jiskoot also offers a multi-tasking real-time dedicatedblending controller, the JiskootInSight®.

The InSight® is an expandablecontroller designed for 2-40stream applications that caneither operate as a stand-alone device or in conjunctionwith a dedicated SCADAsystem and can be integratedwith a plant-wide controlsystem (DCS).The InSight® hasa simple user interface withmulti-level security allowing

Crude oil blender

access to recipe management,alarms, reports and batchinformation.The InSight®

performs all the necessarylinearisation, mass, volume andtemperature computation andcorrection for accurateblending and has many uniquefeatures.

Blending ControlSelection of blender controlphilosophy is dependant uponthe products being blended,the quality of feedstock, thefinal product specifications andthe conditions under whichthe blender will operate. Thecontrol system and algorithms

define the stability andperformance of the blenderand selection of the correctcontrol system is crucial tosuccess.The two main types ofcontrol system for blendingare Ratio Control and QualityTrim

Ratio ControlRatio Control produces aproduct to an extremelyaccurate component ratio.The blender operates oneither a fixed volumetric, ormass ratio. This ratio ismaintained by the closed loopcontrol between the flowsignals from the field

equipment and the controlsignals from the controllerback to the field equipment.The accuracy of a RatioControl blender is determinedby the measurement andcontrol system.

Quality TrimA Quality Trim blenderproduces a final productdefined by a component ratio,but one or more analysersmounted at the exit to theblend header are used to‘trim’ the quality of the finalproduct by adjusting thecomponent ratio. Productquality is continuouslymeasured by the analyser(s)and the final product can beadjusted for parameters suchas viscosity, density andoctane.The accuracy of aQuality Trim blender isdetermined by the analyser(s).

Which to use?Where the ratio and accuracyof each component stream iscrucial, and the quality of thecomponents consistent andunlikely to vary, Ratio Controlis the preferred option.Quality Trim should be used inapplications where there is apossibility of variations in thespecification or quality of thecomponent products suppliedto the blender.

Ratio Control blender

Quality Trim blender

Jiskoot InSight® controller

App

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Jiskoot has supplied hundredsof blenders ranging from smalltwo-stream fuel oil blendersto large multi-stream systemswith analyser trim andSCADA control. Jiskootblenders are supplied skidmounted, piped, wired andtested ready for installation atyour site and guaranteed toperform to yourspecifications. Every blendingapplication is unique andwhilst the basic controlprinciples remain the same,the configuration, selection ofcomponents and design variesfor every application.

Additive injectionThe addition of dyes andmarkers to gasoline and fuelsis a statutory customsrequirement in manycountries.The problem ofinjecting additives into large

pipelines, where the ratiobetween the two streams canbe in the order of 1:1000 ormore, can be solved using aJiskoot Flow ResponsiveAdditive Proportioning (FRAP)System.

Crude oil blendingLow-grade crude oils can beblended with a higher gradefor refining or exportpurposes. Often the blenderuses an analyser to optimisethe blended product for aspecific component such asAPI gravity.

Diesel blendingHigher specification, lowercost diesel can be producedby in-line blending. Blenderscan be designed to take majorcomponents directly fromprocess units to minimiseintermediate tank storage.Using analysers for sulphur

and cetane, the blended dieselcan be produced to an exactenvironmental specification.

Ethanol blendingEthanol is used in a widerange of industries. Beforedispatch from a bonded plant,ethanol is normallydenaturised.This is achievedby blending a variety ofdenaturants with the ethanol.Contamination of sequentialloads with differentdenaturants must be avoidedby incorporating a flushcycle in each batch.

Bunker blender

Fuel oil/bunker blendingFuel oil (or ‘bunkers’) isblended globally. Blenders canbe trailer mounted, mountedon fuel barge decks or shoremounted. They enableoperators to produce anytype of fuel oil within veryclose viscosity and volumetrictolerances from as few as twobase components, normallyHFO and MDO.

LPG blendingThe demand for propane,butane and blends of theseproducts has increasedsignificantly.The search forCFC free propellants and thegrowth in liquid gas fuelproduction has given rise tothe need for propane/butaneblenders. Many systems use adensitometer mounted in theblend header to provide asignal to the blend controllerwhich trims the blend to aspecified density.

Bitumen blendingBitumen blending is anarduous duty. The bitumenhas to be heated and keptmoving and local hot spotsmust be avoided to eliminatecoking and meter damage.Jiskoot was the first companyto use a double case meter ina recycle loop. Bitumenblenders need flushingfacilities to avoid solidificationafter blending.

Lube oil blending anddehydrationLube oil is one of the mostdemanding blendingapplications andconsiderable expertise isneeded to produce aclosely specified productfrom a wide range ofingredients withoutcontamination. Thepatented Jiskoot lube oildehydration system isunique and often employedto dry wet stocks tocrackle test level prior toblending.

LPG blender

Lube oil blender and

dehydration system

Ethanol blender

Mobile fuel oil blender

Solu

tions

Jiskoot is an internationallyacknowledged in-line blendingspecialist. The company doesnot manufacture any flowcomponents and is thereforeable to independently selectand use the best fieldequipment for everyapplication.

Jiskoot systems are designedand manufactured to thehighest standard by engineerswith years of practicalexperience.

Jiskoot is ISO 9000 accredited and all design and manufacturing is done instrict accordance with ISOprocedures.

Jiskoot offers a ‘turnkey’service which includes:

1. The design,manufacture and supply of instrumentation and

terminals tested undersimulated operatingconditions.

2. Selection, sizing,procurement, inspectionand supply of all systemequipment such as flowmeters, control valves,pumps, etc.

3. Design and supply ofcompletely self-containedpiped and wired skids.

4. Supply of site terminationdrawings, wiring diagramsand operation/maintenancemanuals.

5. Certification to siteelectrical/pneumatic/pipingspecifications.

6. Technical supervision ofinstallation teams.

7. Commissioning services

and maintenance contracts.

8. Factory/on-site training ofoperating personnel.

Jiskoot can also provide aconsultancy service for theevaluation of blending projectsand applications.

Propane and butane blender using mass flow meters

UKJiskoot Quality Systems

Tel: +44 (0)1892 518000

Fax: +44 (0)1892 518100

Email: ms-jiskootuksales@c-a-m.com

USAJiskoot Quality Systems

Tel: +1 281 583 0583

Fax: +1 281 583 0587

Email: ms-jiskootusasales@c-a-m.com

Jiskoot Quality SystemsA Cameron Company

www.jiskoot.com

CameronMeasurement Systems

Tel: +1 281 582 9500

Fax: +1 281 582 9599

Email: ms-marketing@c-a-m.com www.c-a-m.com/flo