In the petroleum industry, and within the field of process engineering in general, tank gauging refers specifically to static quantity assessment of bulk liquids in storage tanks. The measurement is usually quantified as Net Standard Volume (NSV, e.g. barrel or cubic meter) or Net Standard Weight (NSW, e.g. lb, ton). The output is calculated based on static data (e.g. tank strapping table) combined with volumetric (level and temperature) or mass (differential-pressure) measurements, or a hybrid between the two.
The measured bulk product can in theory be any type of liquid such as chemicals, bio-fuels or water, stored in any type of container such as caverns, marine tankers or pressure vessels. The most frequent application is however liquid petroleum products stored in non-pressurized storage tanks[1]. These tanks are often classified as hazardous areas, and require the installed equipment to be in compliance with EX requirements. Process industry vessels and simple containers do not usually require tank gauging measurements.
Often 'tank gauging' incorrectly denotes the entire 'automatic tank gauging system'(ATGS), but the measurement procedure itself can either be manual, semi-automatic or automatic. High reliability tank gauging data is critical for the operations of a tank farm, and associated legislate requirements and safety aspects. For example, the tank gauging system is usually the primary method of preventing overfills.
Tank gauging data is also often used for fiscal purposes and custody transfers. Therefore the measurement accuracy becomes critical, especially as most bulk liquid transfers represent a large value. A correctly specified value from a tank gauging measurement shall always come with a measurement uncertainty. Tank gauging therefore employs more rigorous measurement procedures and higher accuracy equipment than 'ordinary' sensors within process industry. Re-calibration (or verification) is often an annual requirement, and some countries require national custody transfer certificates. The tank gauging batch data can also be compared with accumulated flow metering data, or tank gauging measurements done by independent surveyors.
What is tank gauging?
editTank Gauge vs. Level Sensor
Why use tank gauging?
editModern tank gauging nsystem control-room with HMI (but not as complicated as a DCS)
Tank gauging data is often used for the following purposes:
- Oil movement and operations
- Stock Accounting
- Operational Control
- Batch Transfer Handling
- Overfill Prevention
- Pump Control
- Roof Tilt Surveillance
- Inventory Control
- Custody Transfer
- Temperature, pressure, density corrections of observed volume
- Mass balance/Loss estimation
- Leak detection
- Overfill protection
Tank gauging applications
editTank gauging can be applied to virtually any liquid stored in a tank; hydrocarbons and other chemicals. The liquid may be heated, chilled, boiling, agitated Heated secondary containment Aboveground storage tanks (AST) differ from underground (UST) storage tanks in the kinds of regulations that are applied. Biofuels such as palm-Oil and bio-diesel
Liquefied gases Natural gas condensate
underground, bullets, Tank blanketing
While steel and concrete remain one of the most popular choices for tanks, glass-reinforced plastic, thermoplastic and polyethylene tanks are increasing in popularity.
- Tank Terminals
- Oil Refineries, e.g. tank farms and pressurized bullets
- Upstream Oil & Gas
- Strategic Petroleum Reserves
- Military storage
- Marine vessels
- Aviation, e.g. jet fuel tanks at airports
- Storage at chemical and petrochemical processing plants
- Power plants, e.g. fuel tanks
Manual tank gauging measurements
editFor verification. API 3.1A
Automatic Tank Gauging Systems (ATGS)
editThese tanks are often classified as hazardous areas, and require the installed equipment to be in compliance with EX requirements.
Lots of requirements, contact expert, usually the bendors.
Automatic Tank Gauge (ATG) Level+temp automatic, density in lab Hybrid measurement API 3.6
Volumetric measurements
editLevel Sensors
edit
API 3.1B
Automatic Tank Gauge (ATG)
History from F&T to Servo to Radar
Radar
editServo
editFloat & Tape
editTemperature transmitters
editAPI 7 Multi-Temperature Transmitter (MTT)
Hydrostatic (mass) measurements
editHTG
Hybrid measurements
editHuman to Machine Interface (HMI)
editCommunication technology
editOverfill Prevention System
edittest 1234
- Rosemount Tank gauging, Emerson inc (formerly known as 'Saab Marine Electronics AB')
- Honeywell (formerly known as 'Enraf BV')
- Endress+Hauser
test 1234
Tank Gauging Calculations
editOverview
editCalculate the volume correction factors for Petroleum (Crude Oil)Products. Obtain temperature (CTL), pressure (CPL) and combined (CTPL) factors, given a known density, to 60 Deg F and other temperatures and pressures. Calculations are selectable for Crude Oil, Refined Products or Lubricants. Temperature inputs are in Deg F and Deg C. Density inputs are in S.G., API and kg/m3. Pressure inputs are in PSI, bar and kPa. Results are in Deg F, S.G., API, kg/m3, PSI. Will calculate a Base (60 Deg F) density when needed. Product custody transfer, auditing, surveying. Chemical Engineering calculations.
Observed Data
editThe "observed" condition is the temperature and pressure at which the density of a liquid is actually or assumed to have been measured. Calculations can then be performed to correct this observed density to any other temperature and pressure conditions.
Stilling-well corrections
editLevel to Volume (strapping tables)
editTank Bulging
Temperature and pressure compensation tables
editTemperature Stratification
editNet Standard Volume (NSV)
editNet Standard Weight (NSW)
editLiquefied natural gas (LPG/LNG)
editMeasurement Accuracy and Custody Transfer
editGlobal accuracy requirements
editTypical measurement uncertainty analysis
editCustody Transfer Certificates
editFactors affecting the accuracy
editFlow-meters or tank gauging system?
editHealth, Safety and Environment (HSE)
editMajor Accidents
editBuncefield, Jaipur
Ofta växer städer så att terminalerna ligger mitt i staden
Overfill Prevention Systems (OPS)
editSafety Certificates
editCountry | Description | Certifying Body | Legislative Requirement | Comment
|
---|---|---|---|---|
Belgium | Overfill Prevention | VLAREM | TBD | |
Germany | tomt | Overfill Prevention | TÜV/DIBt | WHG (Water Resources Act) |
Switzerland | Overfill Prevention | tomt | BAFU | BUWAL |
(worldwide) | Overfill Prevention | tomt | BAFU | BUWAL |
TÜV/DIBt WHG
Similar regulations exist in Belgium and Switzerland.
In parts of Belgium it is the VLAREM. You can get further information
from AIB Vincotte at www.vincotte.com.
In Switzerland the guideline is called BUWAL. The Federal Office for
the Environment (BAFU) i
Safety Instrumented Systems (SIS)
editEquipment Verification (Proof-testing)
editLeak Detection
editTank Gauging Standards, Manuals and Recommended Practices (RP)
editAmerican Petroleum Institute (API)
editAPI Manual of Petroleum Measurement (MPMS)
3.1B Automatic Tank Gauging 7.3 Temperature Measurements 3.3 LPG Measurements 3.6 Hybrid Measurements 2350 Overfill Protection
International Organization for Standardization (ISO)
editInternational Organization of Legal Metrology (OIML)
editOIML R85:2008
IEC 62591 (Wireless HART)
editTank gauging trends
editOverfill prevention
editReferens till min egen artikel [3]
- ATG + independent overfill alarm
- SIL
- continuous measurement also for overfill
Wireless Data Communication
editRoof Tilt Measurements
editLeak Detection
edit
[Test]
See also
edit- Oil production plant
- Oil-storage trade
- Oil depot
- Oil refinery
- Oil-storage trade
- Buncefield oil depot
- petroleum industry
- Jaipur fire
- Storage tank
ATG[4]
MTG
HMI + proper measurement equipment
http://www.iec.ch/functionalsafety/
IEC Functional Safety Website
(sometimes called a tank farm, installation or oil terminal) is an industrial facility for the storage of oil and/or petrochemical products and from which these products are usually transported to end users or further storage facilities. An oil depot typically has tankage, either above ground or underground, and gantries for the discharge of products into road tankers or other vehicles (such as barges) or pipelines.
Oil depots are usually situated close to oil refineries or in locations where marine tankers containing products can discharge their cargo. Some depots are attached to pipelines from which they draw their supplies and depots can also be fed by rail, by barge and by road tanker (sometimes known as "bridging").
Most oil depots have road tankers operating from their grounds and these vehicles transport products to petrol stations or other users.
An oil depot is a comparatively unsophisticated facility in that (in most cases) there is no processing or other transformation on site. The products which reach the depot (from a refinery) are in their final form suitable for delivery to customers. In some cases additives may be injected into products in tanks, but there is usually no manufacturing plant on site. Modern depots comprise the same types of tankage, pipelines and gantries as those in the past and although there is a greater degree of automation on site, there have been few significant changes in depot operational activities over time.
Ethnic | 1970 | 1980 | 1990 | 2000 | 2009 |
---|---|---|---|---|---|
Chinese | 77.0 | 78.3 | 77.7 | 76.8 | 74.2 |
Malays | 14.8 | 14.4 | 14.1 | 13.9 | 13.4 |
Indians | 7.0 | 6.3 | 7.1 | 7.9 | 9.2 |
Others | 1.2 | 1.0 | 1.1 | 1.4 | 3.2 |
Many of the tanks have a floating roof, to minimize product vapor emissions, which needs to be taken into account by the measurement method e.g. through an insert measurement pipe.
simpler than process
volu vs mass
Most countries regulated
Mass Volumetric
The determination of temperature, API gravity, and suspended
sediment and water of the tank contents a
methods used for these
determinations may be found in the API Manual of Petroleum Measurement Standards (MPMS).
List_of_largest_oil_and_gas_companies_by_revenue
Marine_transfer_operations
Oil storage Category:Petroleum production Category:Fuel containers
Carl-Johan Roos 21:57, 11 November 2013 (UTC)