BTB Oil Refineries
Introduction
Mini-Refineries are skid mounted modular crude oil distillation units (CDU) which process 10,000 BPD of crude oil per year and are capable of producing a variety of finished products including naphtha (straight run gasoline), kerosene, diesel and fuel oil. Two or more plants could be installed on a single site allowing the simultaneous processing of more than one type of crude oil; and one plant can still be in operation in the event one plant is down.
Technical information:
The skid mounted modular crude oil distillation units: -
- Can be set up and in operation within two days after arrival at a site where the foundation and storage tanks are in place.
- A single operator may restart the plant from a cold start and have the plant in full operation in less than two hours.
- Are completely automated and once an operator sets all the controlling points, all product temperatures and flows are controlled automatically. If a product specification drifts off or if a potentially hazardous condition develops, the plant automatically adjusts itself to a safe condition, without the help of an operator and a “first out” alarm signals the reason for the shutdown by a flashing red light. The operator can then make the necessary adjustment or the plant will automatically shut down.
- Only a flat support area or concrete slab without anchor bolts is required to support the plant.
- Requires no water, steam, or instrument air.
- Fuel supply can be natural gas, naphtha, diesel fuel oil or a combination of these fuels.
Typical Refinery Catalytic Process Unit at Wellhead
According to lot parameters :
- Crude quality
- Products specification
- Products quantities
- Products import cost
- Gasoline need
Are numerous arrangements :
- Diesel production
- Special kerosene use
- Asphalt for local need
- Fuel for power plant
- Gasoline significant
Additional options :
The skid mounted modular crude oil distillation units could be equipped with the following additional equipment:
- Special alloy(s) may be included in the plant design
- Desalter packages for removing salt from the crude
- Portable laboratory and control buildings with supplies.
Mini-Refinery Applications :
Traditionally, the petroleum industry has constructed large-scale refineries at centralized locations, supplying them with crude oil and gas condensate via pipeline and transport truck. Refined grades of products are subsequently transported from the refinery to consumer markets, primarily by transport truck. While large-scale refineries provide the bulk of refined products to the world marketplace, the majority of new hydrocarbon discoveries by industry majors and large independents occur in areas where there is limited or no available infrastructure for transportation and refining. Therefore, producers are forced to construct expensive infrastructures for transporting the hydrocarbons to an available refinery, or construct a new refinery at a location near the production site. Under the best of circumstances this process can take several years.
In populated areas near a pipeline or oil field and not near a refinery, a small mini-refinery can be installed that will process crude from the pipeline.
This plant can “thief the diesel” or desired distillate for local consumption, and then injects the unused portion of the crude back into the pipeline.
Each process plant is skid mounted, modular in design and transportable to the source of crude production or a pipeline location. System commissioning at the site, on the small units, can be complete within 48 hours after arrival at the completed site. These units are easily relocated with a minimum amount of field construction. Refined products produced from a mini-refinery processing plant can be sold to local markets or supplied as a feedstock for further processing and the residual oil returned to the crude pipelines.
Additionally, the residual oil product can be used to fuel diesel-electric cogeneration plants for the production of electricity or any heavy oil fired process equipment such as boilers, heaters and etc...
Mini-refineries are particularly effective in areas where there is a ready supply of crude but limited product distribution or refining capacity, where transportation costs or capability present a problem, such as remote areas or offshore platforms.
Cranes must be available to set the skids; it is acceptable to use multiple skids to allow more room for operating the equipment. These skids could be assembled and tested in the shop and reassembled by crane at the site without the need for welders or special technicians.
Plant Operation:
Typically, cold crude oil from off-site storage is received at the topping plant battery limits and pumped by the crude charge pump on flow control. The crude oil exchanges heat with the atmospheric tower product streams. The crude then flows to the crude heater where it is further heated and partially vaporized. The crude heater is a direct-fired radiant-convection heater, designed to burn off gas, natural gas and/or liquid fuel. Constant heater outlet temperature is maintained automatically by controlling the fuel to the heater. Partially vaporized crude oil from the crude heater flows to the flash zone of the atmospheric tower where the vapour and liquid separate. The vapour flows up the tower where it is cooled and partially condensed by reflux to form the side stream products. The liquid joins with the over flash liquid from the first tray above the flash zone and flows to the reduced crude stripping section in the bottom of the atmospheric tower.
The overhead vapour from the atmospheric tower is cooled and partially condensed in the overhead condenser and flows to the overhead accumulator where liquid unstabilised naphtha, water and uncondensed gas separate. The water is automatically withdrawn from a boot on the overhead accumulator and flows off-site.
A portion of the liquid naphtha from the accumulator is returned to the top of the atmospheric tower as reflux to maintain the overhead vapour at a constant temperature and the remainder flows to off-site storage. Uncondensed gas from the accumulator flows on backpressure control to be used as supplemental fuel for the crude heater.
Unstripped side draw product flows on tower temperature control from its draw tray on the atmospheric tower to its stripper. The side draw product is stripped with re-boiled vapour to control the flash point. Product flows from the bottom of the stripper on level control is cooled by exchanging heat with crude, and then flows to battery limits.
Reduced crude product is pumped from the bottom of the atmospheric tower on level control through the re-boiler, and is then further cooled by the reduced crude/crude exchangers before flowing outbound to battery limits.
Since the side stream stripper is re-boiled with hot tower bottoms, the plant does not require steam. However, nozzles are provided on the tower and stripper for steam stripping, if required. The only requirement for water is for a desalter if one is included.
Product specification :
The refinery will produce products with the following specifications:
Gasoline: TBP ? C 45-165
Kerosene: TBP ? C 170- 235
Gas Oil: TBP ? C 235- 370
- Sulphur content will be according the Crude oil to be processed.
- It is assumed that the products will be pumped to the existing storage tanks before shipping to the consumers.
- Produced heavy fuel will supplied to the main storage tank of the existing power plant (100 MW range).
Crude oil specification:
It is assumed that the refinery will process light crude oil withdrawn from the existing storage tanks.
Table (1) CRUDE OIL GENERAL CHARACTERISTICS
| Result |
Test |
| 0.8413 |
Specific Gravity 60 ºF/ 60 ºF |
| 36.7 |
API Gravity |
| 5.5 |
Reid Vapour Pressure , Psi |
| 8.25 |
Kinematics Viscosity @ 20 Cº, CST |
| 5.1 |
Kinematics Viscosity @ 38 CºC, CST |
| 0 |
Water (D95), vol % |
| < 0.05 |
B.S and W, vol % |
| 0.05 |
Sediment (D473) ,wt% |
| 2.4 |
Salt content( NaCl),lb/M bbls |
| 0.55 |
Sulphur , wt% |
| 0.0003 |
Mercaptan sulphur, wt% |
| < 1 |
H2S, ppm |
| 0.1 |
Nitrogen ,wt% |
| 86.3 |
Carbon, wt% |
| 13.05 |
Hydrogen, wt% |
| - 6.7 |
Pour point, C |
| - 2 |
Flash point, C |
| 0.29 |
Acid number, mg KOH/g |
| - |
Gross Calorific Value, Kcal/Kg |
| - |
Net Calorific Value, Kcal/Kg |
| 11.86 |
Characterization Factor, UOP K |
| 0.003 |
Ash content, wt% |
| 8.06 |
Wax content, wt% |
| 0.48 |
C7 Insolubles ,wt% |
| 1.99 |
Conradson Carbon ,wt% |
|
Metals |
| 6.3 |
Nickel |
| 4.7 |
Vanadium |
| 1 |
Iron |
| < 0.1 |
Lead |
| < 0.1 |
Copper |
| 2.1 |
Sodium |
| - |
Asphaltenes |
Contact us for more information
Email: info@btbgroup.co.uk
Telephone: +44 (0) 845 057 4002
Mobile: +44 (0) 7834 741031
Fax: +44 (0) 845 057 4002
Address
Uk Head Office
The Coach House
43 Main Street
Rotherby
Leicestershire LE14 2LP
England