An Integrated Analytical Process GC and SHS Based on IS CAN Communication

Circor Tech

Patrick Lowery

ABB Analytical

Tracy Dye

IFPAC 2008

Baltimore

Vision

An integrated process analytical system that receives, sends and acts on critical multivariate data to monitor, communicate and control its status and health via any networked client.

NeSSITM Value Proposition

Improved System Reliability and Serviceability

Reduced Capital Costs

Reduced Operational and Maintenance Costs

Innovative, Early Adopter Market

? Time

Prevalence

Gen 2

Gen

1

Achieving the stated vision and value proposition in an innovative, early adopter market dictates the need for a phased, risk reduced approach.

Phased Market Approach

Phase 1 – Connectivity Hybrid communication system

Discrete analog outputs for single signal devices

Discrete digital inputs

IS CAN networked components for multivariate data devices

Basic control Temperature, flow, filtration backup, valve switching

Basic indication Sample flow, ΔP, temperature

Phased Market Approach

Phase 2 – “Self Describing” All SHS components have open standard

description file (EDDL, XML, etc.)

Real time operational view of SHS on any networked client

Fully integrated process analytical system

IS CAN for the NeSSITM Communication Bus

“Plug and play” in Div 1/Zone 1 classified areas

CAN is everywhere in demanding applications (marine, auto, aerospace)

Balanced signaling (differential drive) enables superior noise rejection (relative to unbalanced single end) especially over cables

Open and Standard, already built in … Data Integrity Mechanisms

Integral Bus Error Recovery and Self Correction

Message Prioritization Via Non-Destructive Arbitration

Mature and Well Defined Application Layers Such As CANopen

Master to slave or peer to peer communication This allows individual devices to contain their own alarms and setpoints

Allow for the system to interact with other devices in the system without the “SAM”

Smart SHS Topography

What is needed to ascertain status of SHS? Power

Pressures

Flows

Temperature (both ambient and actual fluid temp)

System valve status

Filter “health” (need two signals, either pressure/flow, or pressure & differential pressure)

Example of basic smart sample system topography

Smart SHS Topography

FIBER OPTIC CAN CABLE

(ENTIRE GC CONTROL ON FIBER OPTIC CANopen NETWORK

ANALOG I/O & IS BARRIERS, IF NEEDED

SAMIS POWER

SAMPLE SYSTEM

CABINETHEATER INTRINSICALLY

SAFE CANbus

ANALYZER LOWER LEVEL NETWORK

PROCESS CONTROL NETWORK

DCS SYSTEM AND FIREWALL/ NETWORK SWITCHING STATION

Smart SHS Topography

BYPASS FAST LOOP FLOW, TEMP, PRESSURES

FILTER HEALTH

(FLOW AND DIFF PRESSURE)

VALVE STATUS

FLOW TO ANALYZER

GC ATM REFERENCE PRESSURE

DIFF PRESSURE AND FLOW ACROSS STREAM SELECT

POWER MONITOR AND DEVICE INVENTORY/ HEALTH FROM CAN TO SAM

WHAT IS “SAM” There is no industry consortium on the definition of SAM (Sensor

Actuator Manager)

The definition of SAM in this system topology is: Bridge between C1D1 (Zone 1) and C1D2 (Zone 2) for CAN

communications

Integrated analog I/O to digitize 4-20mA devices

Obtains inventory of all CAN networked devices using IEEE virtual TEDs concept (i.e. device profiles/ data sheets)

Monitors total IS can bus power consumption and health

Has a basic application interface that can pass alarm triggers and set points down to devices and pass alarms and data up to GC

GC is not the sample system master per se, but a data server

Future upgrade path for CAN device metadata to provide system configuration data up to HMI at GC interface

Comparison to Traditional/ Legacy SHS Purely mechanical SHS

Lower initial capital cost, but no data from system

If system goes down, analyzer goes down, process is diverted or fines can occur (in emission monitoring applications)

EPA requires backfill of worst case data for emission monitoring analyzer downtime, average of $15-25k per event

Higher cost in human “capital” and higher average analyzer down time

One refining case study found an average of 6 hours of process down time (per event) from time of DCS alarm to time that analyzer/ process chemistry was verified

6 hours of process downtime = BIG $$$

Comparison to Traditional/ Legacy SHS Analog instrumented SHS (GEN 1.5)

Analog devices (in most but not all cases) are less expensive

No multi-variate data from single device

All devices must be discreetly wired and must have

Discreet IS barrier

Analog I/O module to PLC or data logger

PLC or data logger

Ethernet or other field bus communications module

Data can be shown that digital bus implementation can reduce overall system cost

~$300 per sensing point cost savings on pressure/temp sensing

~$2000 per sensing point on flow, including cabling/wiring cost

~20-30% reduction in needed modular or fitting hardware

~40% reduction in wiring/ installation / integration cost

Still challenges ahead Although major technical hurdles are being addressed,

there are still some market challenges ahead

Further reduction of cabling cost needed along with some more choices of chemical compatibility options

New types of power levels and digital bus implementation at IS certifying bodies

More IS power supply vendors needed

Further reduction in component costs can be realized by economy of scale (although highly expensive gen 1.5 systems have been economically justified at several large refineries)

Still opportunities ahead GEN 2, digital bus SHS also provide new opportunities

Integration of “grab bag” closed-loop sample system with continuous GC SHS for validation

Can differentiate between analyzer problem and SHS problem; if analyzer isolated as problem, can automatically route sample to sample cylinder for lab analysis

Can localize heating solutions with tighter control or vaporize liquid samples near source to GC, remove the need for problematic liquid inject valves

XML metadata into device profiles for graphical representation on HMI displays

Integration of continuous analyzers along with associated SHS onto analyzer network