new system overview for liquids scheduling - technotradepipeline... · 2018. 7. 7. · the...

System Overview for Liquids Scheduling

January, 2011

PipelineScheduler® 2

CCCOOOPPPYYYRRRIIIGGGHHHTTT

This is an unpublished work, the copyright of which vests in Energy Solutions International. All rights reserved. The information contained herein is the property of energy solutions and is supplied

without liability for errors or omissions.

No part may be reproduced or used except as authorized by contract or other written permission. The copyright and the foregoing restriction on reproduction and use extend to all media in which the

information may be embodied.

PipelineScheduler® I

TTTAAABBBLLLEEE OOOFFF CCCOOONNNTTTEEENNNTTTSSS

1. INTRODUCTION ........................................................................................................................................ 2

2. SCHEDULING WORKFLOW ..................................................................................................................... 3

3. FEATURE OVERVIEW .............................................................................................................................. 4

3.1 USER INTERFACE ................................................................................................................................. 4 3.1.1 Navigation ...................................................................................................................................... 4 3.1.2 Visual Pipeline Schematic ............................................................................................................. 4 3.1.3 Context Sensitivity ......................................................................................................................... 5 3.1.4 Construction Mode ........................................................................................................................ 5

3.2 SCHEDULING ........................................................................................................................................ 5 3.2.1 Nominations Driven Scheduling .................................................................................................... 5 3.2.2 Terminal Demand Driven Scheduling ........................................................................................... 6

3.3 BATCH PLANNING ................................................................................................................................. 6 3.4 SCHEDULE SIMULATION ........................................................................................................................ 7 3.5 ADVANCED FEATURES .......................................................................................................................... 9

3.5.1 Blending ......................................................................................................................................... 9 3.5.2 Event Management ..................................................................................................................... 10 3.5.3 Tank and Terminal Management ................................................................................................ 10 3.5.4 DRA Effect Modeling ................................................................................................................... 11

3.6 REPORTING ....................................................................................................................................... 11

4. TECHNICAL SPECIFICATIONS ............................................................................................................. 13

4.1 SYSTEM TECHNOLOGY ....................................................................................................................... 13 4.2 PLATFORM REQUIREMENTS ................................................................................................................ 13 4.3 SYSTEM INTERFACING ........................................................................................................................ 13

4.3.1 Energy Solutions Systems Integration ........................................................................................ 13 4.3.2 Third Party Systems Integration .................................................................................................. 13

5. DEFINITIONS ........................................................................................................................................... 14


111... IIINNNTTTRRROOODDDUUUCCCTTTIIIOOONNN

From the wellhead to the market, pipeline companies face many challenges. Among these, pipeline scheduling is a key step in the critical path. The ability to move crude oil and refined products from one point to another as efficiently and economically as possible is the lifeblood of a pipeline company. The fact that pipeline transportation is rate controlled only serves to emphasize liquids scheduling as a key area where pipelines can optimize their operations for increased profit.

PipelineScheduler is a total software solution for pipeline scheduling. It organizes and consolidates all information required to generate short and long term schedules for liquid pipeline movements. PipelineScheduler helps pipeline companies schedule their pipelines efficiently and rapidly within a single application.

The PipelineScheduler solution includes: Nominations management Comprehensive pipeline and terminal scheduling Automated reconciliation between scheduled and actual operations Support for accounting and commercial groups Efficient, centralized information distribution

PipelineScheduler is a comprehensive, fully featured system designed to manage the commercial and operational data that are necessary to operate a pipeline efficiently. It allows the user to rapidly collect shipping requests and create a working schedule and manage that schedule through its active period. Schedules can be created based on nominated volumes or management of terminal inventories, or any combination of these. By consolidating data from nominations through batch planning, schedule revisions and interfacing with operations, PipelineScheduler can provide a central data repository to standardize information management for accounting and marketing groups, operations, engineering, and management.

This document provides an overview of the PipelineScheduler solution, including the system architecture, features and functions, and benefits of using PipelineScheduler for liquids scheduling.


222... SSSCCCHHHEEEDDDUUULLLIIINNNGGG WWWOOORRRKKKFFFLLLOOOWWW

PipelineScheduler is designed to support the entire scheduling workflow, from initial nominations or tank lifting forecast to generating the pumping schedule for operations.

Figure 1: Scheduling Workflow

Figure 1 represents the standard liquids scheduling workflow. PipelineScheduler includes support for all steps in this workflow, including direct interfacing capabilities with SCADA and Accounting systems. Section 3 of this document describes in more detail the capabilities of the PipelineScheduler solution.


333... FFFEEEAAATTTUUURRREEE OOOVVVEEERRRVVVIIIEEEWWW

3.1 User Interface

The PipelineScheduler user interface is designed to make information easily available to the user and provide an intuitive environment for batch scheduling and optimization.

Figure 2: The PipelineTransporter graphical user interface

3.1.1 Navigation

The PipelineScheduler solution uses tree navigation pane on the left hand side of the application to allow users to select from multiple pipeline configurations, and from multiple simulation cases for each configuration.

3.1.2 Visual Pipeline Schematic

PipelineScheduler displays a visual pipeline schematic to allow the user to rapidly process scheduling information. Figure 2 shows how this schematic representation can be displayed at the same time as other tabular information, such as the batch plan. In addition, the schematic can be visualized full screen for visual schedule review and


pipeline configuration. The labeling in the schematic can also be configured by the user, as can the choice of colors for each product.

3.1.3 Context Sensitivity

Objects in the pipeline schematic are context sensitive, allowing users to easily determine the properties of any pipeline, tank, or terminal with a simple right mouse click. Users can also chart properties of the pipeline (e.g. flow rate, linefill, etc) or tanks and terminals (e.g. tank volume, level, available capacity, etc) by simply right clicking on the relevant object. Figure 3 shows the context sensitive data presented when clicking on a tank in the schematic.

Figure 3: Context sensitive tank properties

3.1.4 Construction Mode

The construction mode window allows the user to graphically build a model network within the same visual representation as the pipeline schematic. The model network may contain supplies, deliveries, pumps, pipes, junctions, and tanks. The user may place the objects into the schematic and connect the objects together to build the desired configuration. The corresponding data tables will be populated with data based on the constructed configuration.

3.2 Scheduling

PipelineScheduler generates an operational schedule based on either nominated volumes or terminal requirements for the scheduling period.

3.2.1 Nominations Driven Scheduling

The nomination module will assist the scheduler in validating the nominations before processing them into the batch plan. When using PipelineScheduler in a nominations-based environment, the nominated volumes may be automatically retrieved from external nominations systems, from files (e.g. MS Excel, CSV) or entered manually. These volumes can be viewed and edited by the scheduler in the PipelineScheduler user


interface. The scheduler can accept or reject the nominations and send this information and comments back to the shipper via email or through an interface to an external system.

The nominations screen allows the user to enter the volumes and origin/destinations of the product types that are nominated to move on the line for the month.

Figure 4: Entering nominations

3.2.2 Terminal Demand Driven Scheduling

Schedules may also be generated based on demand. This type of scheduling derives volumes to be scheduled from terminal requirements. The scheduler can edit the daily liftings for each tank or product pool, as well as specific lifting modifiers to account for specific increases or decreases in lifting volumes. PipelineScheduler generates the total terminal requirements from this data, which are then used as “nominated volumes” for the scheduling process. The scheduler generates the batch plan from the terminal requirements.

3.3 Batch Planning

Once terminal demands or nominations have been processed, the next step is to split the volumes into batches and create a batch plan. The batch plan includes batch names, product type, planned delivery and injection locations (points) and batch sizes (volumes). The batch plan is an ordered list of records that determines the priority of batch activities. For most companies, a batch plan is generated towards the end of the month prior to the scheduling month.


After the Batch Plan is generated, the scheduler can begin the process of generating the schedule, viewing the results, and making adjustments. The scheduler can manipulate the batches within the Batch Plan using standard cut and paste, drag and drop Windows functionality to refine the batch plan for the scheduling period. Batches may be inserted and deleted and rates/operations adjusted and new schedules generated for review. The schedule is generated by clicking a button in the user-interface and results are automatically displayed. Additional input screens can be used to specify triggers, which are used to implement time or volume based rate or system changes, and are taken into account when the schedule is generated. Pipeline maintenance constraints and limitations can also be defined as event triggers; please see section 3.5.2 for more details on event triggers.

For many pipeline companies, when all of the nominated product cannot be scheduled in a month, there is a prescribed method of prorating the nominations. PipelineTransporter can compare the requested product volumes to the capacity of each line for each cycle. If the requested nominations are greater than the available capacity, automated proration calculations can make necessary adjustments complete the schedule.

The scheduler can manipulate virtually every aspect of each batch, including: Batch origination and pumping at mid-line locations Injections at a fixed rate or percentage of mainline rate into an existing batch Full line injection into an existing batch with the upstream line shut in Fixed rate or percentage of mainline rate strip deliveries Specification of a fixed volume to bypass a terminal before initiating a strip or

injection, between successive activities in the same batch, or after the end of the last activity

Automatic strips and injections which can be specified to occur at the slowest possible rate that the requested volume can be delivered without violating any flow limits or slowing down the mainline flow

Synchronized activities, such as a simultaneous full-line delivery of one batch and pumping of another batch at the same location. The two activities are synchronized to complete at the same time

Rule-based routing of batches based on origin, destination, and product in complex pipeline networks

3.4 Schedule Simulation

Once the Batch Plan has been reviewed, the user runs the Schedule Simulation to determine whether the proposed batch plan is valid. Simulation of complex batch plans is completed in seconds, allowing users to rapidly assess modifications made to the batch plan to optimize their schedule.


Any exceptions to defined terminal or tankage limits are automatically recorded in the Alarm log for review. Once the simulation is complete, the user can visually review the results in the pipeline schematic. Pipeline linefill and tank inventories are proportionally represented to scale in the schematic so that the user can easily identify tank overfills or dryouts, pipeline bottlenecks, and other operational challenges.

Figure 5: Simulation schematic

In Figure 5, four key visual cues have been highlighted for clarity in this document. Tank 2FO has been magnified to show the representation of a dry tank; note how the product level is illustrated below the bottom of the tank icon. Tank CN 93 has also been magnified to illustrate a tank overfill; in this case the product level is clearly above the level of the tank icon.

The other two areas of interest in this diagram illustrate the operating conditions on our pipeline. The pipeline to the North Terminal is currently shut down, which is visually represented by the cross-hatched pattern on that pipe segment. The pipeline to the South Terminal, on the other hand, is currently running at maximum capacity, and represents a bottleneck for the entire system. This is visually indicated by the yellow border around that pipe segment.

Segment Shutdown

System Bottleneck


All exceptions to defined operating parameters are recorder to the simulation log. Navigation through the visual representation is synchronized with the log to allow users to rapidly focus on trouble spots using the slider at the bottom of the schematic representation.

Figure 6: Synchronized visual navigation of simulation and alarms

Figure 6 shows the alarm record for a tank low level violation highlighted; the schematic in the lower pane shows the status of the entire pipeline at that exact point in time, allowing the scheduler to rapidly identify remediation strategies to re-route, re-sequence or re-size the batches in the batch plan for optimum performance and efficiency.

3.5 Advanced Features

3.5.1 Blending

PipelineScheduler allows the user to specify default recipes to be used for each product in the system. These recipes can be overridden on a batch basis by editing the recipe assigned to each batch in the batch plans. Blend recipes are defined as proportions of other products in the system, and scheduling a blended product will automatically be reflected in inventories of the individual components of the blend.


3.5.2 Event Management

PipelineScheduler includes sophisticated event management capabilities. Events on the pipeline are handled by “Triggers” that are automatically incorporated into the schedule simulation. Triggers allow the user to define special events that should occur during the simulation period, and that can affect the compilation of the schedule. The triggers can be set to occur at a pre-defined time, for example schedule pump maintenance, or the user can set a trigger to fire once a specific amount of product in a specified batch has passed a specified location in the pipeline network

The following trigger types are available:

TRIGGER DESCRIPTION

Shutdown Shutdown shutdown triggers are used to shutdown the entire line. If duration is entered in hours, then the line will automatically start back up when this length of time has passed. If the duration is left empty, then the line will stay shutdown until a startup trigger occurs.

Startup Startup trigger are used to start the line back up after a shutdown has occurred. They are only needed when the shutdown does not specify duration. This is useful when a shutdown is to be based on a volume activity, while the startup will be based on a timed event.

Minimum rate change Minimum rate change triggers are used to change the minimum flow rate that is allowed at a specified location.

Maximum rate change Maximum rate change triggers are just like minimum rate change triggers, but they change the maximum rate.

Rate change Rate change triggers can be used to change the rate at a specific location at a specified time.

Tank Service change Tank Service change triggers are used to change which product a tank is currently servicing. All fluid leaving a tank will by default be assigned the tanks current product service. The new product that is selected must be one of the possible fluids configured for this tank or group of tanks. The tank service change can begin with an event or on a day/time.

Delivery Delivery (or take-off) triggers are used to schedule a take-off or injection at a specific time.

3.5.3 Tank and Terminal Management

While in some cases, pipeline operators are strictly concerned with the movement of products through their lines, in many cases a true solution must also support terminal and tank inventory management.

PipelineScheduler includes sophisticated inventory management capabilities to meet this requirement. Terminals can be defined with as many tanks as required to support the scheduling function. Tanks can be managed individually or as tank pools, and can be restricted to single products or be configured to support multiple products. Furthermore,


tanks can be taken offline at any time, including automatically based on a specified time, volume or batch.

3.5.4 DRA Effect Modeling

PipelineScheduler can be configured to model the effect of DRA (Drag Reducing Agent) on product movements. The DRA configuration is managed by defining supplementary flow rates for products with which DRA’s may be used. The scheduling engine will then take the accelerated flow rates into account during the schedule simulation.

DRA usage can be defined as a general rule for a selected product, or individually on a batch-by-batch basis. The flow rates defined for DRA addition are expected to reflect a user determined average effect over the course of each pipeline segment for the selected DRA and product.

3.6 Reporting

Since the individual expertise of a scheduler is the critical factor in optimizing a pipeline schedule, PipelineScheduler provides a highly visual, information rich interface for the user to review the schedule data. As indicated in Section 3.1 of this document, the user interface is context sensitive, allowing the user to easily generate visual representations of the schedule data. Below are some example charts that can be simply generated with a mouse click:

Figure 7: Synchronized Tank Volume Chart


Figure 7 above show a chart of tank volume over the course of the schedule simulation. This chart includes high and low limit lines, and clearly shows where the volume in the tank will exceed the tank capacity.

Other typical profile values include pressure, head, velocity, flow, density, and viscosity. Typical trend values include pipeline flows and tank levels.

Figure 8: Example Railroad Chart

The Railroad Chart in Figure 8 displays an entire schedule in a single graph. The name comes from early days of railroad scheduling and many schedulers still prefer this format. The Y axis of the chart shows the distance down the pipeline and the X axis shows time through the schedule. A line depicting the position of the head of each batch tracks through the schedule. Charts are color coded by batch product. Injection and delivery activities are marked on the chart, along with information such as flow rate and total volume.


444... TTTEEECCCHHHNNNIIICCCAAALLL SSSPPPEEECCCIIIFFFIIICCCAAATTTIIIOOONNNSSS

4.1 System Technology

PipelineScheduler is written in Microsoft Visual C++ for the Windows platform. It uses a proprietary data storage architecture designed to provide the maximum performance possible during schedule simulation. The graphical user interface is highly configurable to adapt the menu and toolbar selection choices to the customers requirements. This can simplify user training and system support, and allow customers to rapidly deploy PipelineScheduler within their organizations.

PipelineScheduler also includes direct interfacing capabilities with Microsoft Excel for easy reporting and data export.

4.2 Platform Requirements 512MB RAM 100MB disk storage Windows 2000 Pro or XP Microsoft .NET Framework 2.0 Microsoft Excel 2003 or higher Java 1.4.2 or higher

4.3 System Interfacing

4.3.1 Energy Solutions Systems Integration

PipelineScheduler is a strategic part of an overall pipeline management suite from Energy Solutions. PipelineScheduler can be tightly integrated with PipelineScheduler ®, which supports real-time transient hydraulic simulation, operator training, leak detection, and more. This tight integration can provide all members of the pipeline operations and scheduling organization with rapid communications and awareness of current pipeline status and upcoming events based on the schedules generated by PipelineScheduler.

4.3.2 Third Party Systems Integration

PipelineScheduler is specifically architected to allow integration with third party systems, regardless of platform or technology. From simple file based exchanges to direct interfacing through web services, PipelineScheduler can be a tightly integrated into the customer’s information systems landscape. Energy Solutions has successfully integrated PipelineScheduler with SCADA systems, ERP tools, accounting systems, tank inventory management systems, and more.


555... DDDEEEFFFIIINNNIIITTTIIIOOONNNSSS

In order to provide a better understanding of the capabilities available in Energy Solutions’ technology, this section lists and defines a set of concepts related to the transportation cycle that will be used in this document.

Allocation – Division of pipeline capacity among shippers. When nominations exceed capacity prorating is required.

Batch – A discrete volume of fluid in a pipeline. A batch is defined somewhat differently at different pipeline companies, but generally a batch is made of a single product grade, has a predefined route of travel, and has a defined set of one or more shippers. Most often pipeline companies will also have a term to refer to a group of batches which contain a single product type adjacent in the pipeline.

Batch Plan – An ordered list of batches. The batch plan provides a defined sequence of batch movements, including details on how each receipt or delivery will take place and how each batch will move through the pipeline.

Bottleneck – A point in the pipeline network that limits additional flow.

Capacity calculation – An optimization mode in which the fastest possible simulation of the batch plan is run.

Constant-percent Injection – An injection that occurs at a constant fraction of the main line flow.

Constant-percent strip: A delivery of product into a lateral pipe or a tank that occurs at a constant fraction of the main line flow.

Dynamic power optimization – An optimization mode in which the schedule is generated in order to minimize power usage and power cost.

Cycle – A period of time set by the scheduler, typically a few weeks, used in defining the time required to move a group of products through the pipeline.

Cycle Plan – A list of products and volumes that will be transported in the pipeline. Creation of the cycle plan is the first step in the scheduling process. The cycle plan is created from the nominations received for the pipeline.

Daily Scheduling Process –Pipeline schedulers perform accounting tasks and make schedule adjustments, often on a daily basis. Accounting tasks include supporting the completion of each batch movement and the closure of each ticket. The scheduler typically starts each day by first reconciling the actual movements with the scheduled movements. The schedule may need to be re-generated to reflect changes due to operational changes or shipper requested changes.

Fixed-rate injection – An injection that occurs at a constant flow rate.

Fixed-rate strip – A delivery of product into a lateral pipe or a tank that occurs at a constant flow.

Full-line strip – A delivery of a product into a lateral pipe or a tank that shuts down the main line downstream of the strip location during the delivery.


Fungible vs. Non Fungible Batches – Often fluid in a pipeline meets a defined set of specifications and shippers agree to accept any product that meets that specification, rather than insisting on receiving back the exact physical barrels of product that they put into the pipeline. Batches containing this type of fluid are called fungible batches. The majority of product pipelines around the world move fungible product. Operating with fungible batches gives a pipeline operator significant flexibility in meeting a schedule and so are usually associated with lower tariffs. Most fungible pipelines will also maintain non fungible or segregated batches for a higher tariff.

Monthly Scheduling Process - Standard procedure for batched pipelines is to accept nominations in the weeks prior to the next “scheduling” month, usually corresponding to a calendar month. The first step is to generate a cycle plan or batch template from the nominations. The cycle plan is further refined by generating a batch plan. If nominations exceed the maximum pipeline capacity the scheduler apportions capacity among the shippers using a pre-defined plan. The batch plan is then used generate a system schedule. The system schedule is sent to shippers and pipeline operations staff, usually a few days before the scheduling month begins. Modifications may be made during the scheduling month. If this is necessary, the required changes are made to the batch plan, the scheduling simulator is re-run, and the revised system schedule is distributed.

Nomination - A nomination is a request to move a certain volume of a specified product type along one of the approved pipeline routes.

Off-peak period – A period in a power contract for which rates are lower due to decreased demand. Time in power contracts is divided between on-peak periods and off-peak periods.

On-peak period – A period in a power contract for which rates are higher due to increased (peak) demand. Time in power contracts is divided between on-peak periods and off-peak periods.

Pump selection mode – A station optimization mode that optimizes the pump selection within a station to achieve maximum throughput.

Prorating – The process of apportioning pipeline capacity among shippers using a pre-defined plan when nominations exceed capacity.

Reconciliation – Matching actual events to scheduled events and determining the subsequent effects (if any) on the schedule.

Route – A predefined pipeline section that goes from an origin point to an ending point, including inlets and outlets. The products transported through this route are received or injected at one or more of the inlet points and delivered at one or more of the outlet points.

Shippers – Companies using the transportation facility of a pipeline company.


System Schedule – Information regarding product movements on the pipeline, usually organized by locations to show products and volumes by time for the schedule period. The System Schedule is used by operators to manage activities on the pipeline, on a daily basis. This information may also be called an operational schedule or location report.

Tariff – The fee for transporting product in a common carrier pipeline. Tariffs are usually based on travel distance and product type. Tariffs will be different for fungible and non-fungible batches.

Ticket – A formal record of the transfer of fluid, either a physical transfer or a custody transfer (between the custody of a shipper and the pipeline operator or between custody shippers).

TECHNOTRADE

7-A, Bank Square Market Model Town Lahore Tel: +92-42-35832403Fax: +92-42-35832467

Email: [email protected]: www.technotrade.com.pk

new system overview for liquids scheduling - technotradepipeline... · 2018. 7. 7. · the...

Documents