Dual purpose unrefined/refined petroleum intermodal tank container

Abstract

A dual-purpose tank container is provided, designed for transporting unrefined or refined petroleum, together with a transportation process optimized to utilize available weight limits of transportation means and eliminate unproductive deadheading. The tank container includes inner tank and outer insulation shell, the inner tank being equipped with one or two diaphragms so that a fluid, for example crude oil or gasoline, can fully occupy inner space without risk of contamination from a residual fluid.

Claims

1. Intermodal pressurized insulated tank container adapted to accommodate loading or unloading- of unrefined and refined liquids at same or separate times, comprising of at least two compartments separated by flexible and formidable diaphragm, while avoiding fluid cross contamination.

2. Logistic process of unrefined/refined petroleum transport by a dual-purpose intermodal tank container, set forth in claim 1, comprising the steps of: a) Loading unrefined petroleum of sufficiently low viscosity into insulated intermodal tank container; b) Transporting the intermodal tank container using a road truck trailer chassis from petroleum production source to a railway container yard; c) Transporting the intermodal tank container using a standard intermodal train to a seaport; d) Loading the tank container onto a container steamship equipped with pumps; e) Transporting the loaded steamship to a refinery berth; f) Unloading the unrefined cargo and simultaneously loading a refined petroleum into secondary compartment of the dual-purpose container tanks; g) Transporting the refined petroleum by steamship to another destination; and h) Unloading the refined petroleum from the container tanks.

3. The process of claim 2, but with the steps in the order f, g, h, a, b, c, d, e.

4. Multipurpose Ro-ro ship, as mentioned in claim 2, with specialized plumbing, pumping and blending equipment, capable of unloading or loading of multiple intermodal tank containers, set forth in claim 1, while reaching desired unrefined/refined petroleum properties of the final blend.

5. Multipurpose Ro-ro ship, as set forth in claim 4, but solely or additionally equipped with specialized plumbing, pumping and blending equipment adapted for handling of subzero cryogenic liquids, capable of unloading of multiple specialized intermodal tank containers, loaded with liquefied natural gas (LNG) or liquefied petroleum gas (LPG), while reaching desired properties of the final natural gas blend.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0020] FIG. 1 is an example of cross sectional side elevation of an embodiment of an intermodal tank container of this invention, to provide context.

[0021] FIG. 2 is a schematic flow diagram showing ideal transport process of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Referring to FIG. 1, there are two designs of the intermodal container tank considered. Small version which is 20 feet long (TEU), 8 feet wide, 8.5 feet high, and large version 40 feet long (FEU), 8 feet wide and 8.5 feet high. TEU has cargo weight capacity approx. 24 tones, FEU approx. 45 tones. FEU weight is non-standard for a similar container of such size, but it is still within limits for Canadian road transport, which is 63 tones for a truck GVW (Gross Vehicle Weight) (Alberta, 2018). In most of US states the road GVW weight limit is 80000 Lbs. (Transportation, 2003), which technically prevents road movements of FEU container tanks within US. Although is FEU nonstandard and overweight, it is still within the limits of mainstream heavy duty standard container yard lifting equipment. TEU intermodal tank has two compartments divided by a single diaphragm. FEU has three compartments, divided by two diaphragms. The two diaphragms form one middle and two divided compartments at each end. The volumes of the middle and the two side compartments together are equal when filled up, thanks to the plasticity of the dividing diaphragms. The side compartments are designed for unrefined petroleum, where the diaphragms provide secondary containment measure in case of the tank wall breach (dividing the tank volume of 300 barrels into 2150 barrels). Middle compartment is designed for refined petroleum. All three compartments have their own excessive vacuum breaker valves and overpressure control valves together with dedicated manhole. They are also equipped with pressure and tank level sensors. Referring to FIG. 2, the steps expected in the use of the intermodal tank container designed for transportation of unrefined/refined petroleum fluid include: [0023] 1. Unrefined petroleum, preferably in high temperature and low viscosity, is transferred from a storage tank to the intermodal insulated pressurized tank container using either standard oil pump or specially designed loading pump. While loading it is possible to inject chemicals and diluents to adjust the petroleum properties to the desired level. [0024] 2. The container tank is transported from the loading station, to an intermodal rail yard, using standard truck trailer chassis. [0025] 3. At the intermodal rail yard, the container tank is transferred from truck chassis to a railway flat car, preferably a multiunit double stack well car, using standard lifting and stacking equipment. [0026] 4. A train transport container tanks to an intermodal sea port, where are the container tanks transferred onto a container steamship equipped with unloading pumps. [0027] 5. Because most of world's refineries is located near waterways, the container steamship travels from the sea port to a refinery berth. [0028] 6. At a refinery berth, steamship unloading pumps unload the unrefined petroleum and load refined petroleum into the container tanks secondary compartment. [0029] 7. Steamship departs refinery berth and arrives back at the intermodal seaport. [0030] 8. The container tanks are unloaded from steamship onto a train well cars and transported to the unrefined petroleum production source. [0031] 9. The refined petroleum cargo is optionally unloaded along the way or is utilized at the petroleum production source as a diluent.

[0032] The above steps can be reduced to simpler transporting of container tanks using train from a loading source to a refinery and back without utilizing seaways.

[0033] Viscous bitumen, produced in the Canadian province Alberta, as an example of unrefined petroleum, carries a significant market price discount. There are two factors forming this discount, qualitative and geolocational. The bitumen is very heavy and sour crude with 4% sulfur content and 20% volume of asphaltenes (Strautz, 1977). It had been easier to refine lighter crude oil grades until advent of more complicated refining processes such as coking and hydrotreating. For such complex refineries, extra heavy crudes represent so called opportunity crudes, which are harder to refine, but yield more product volume especially when natural gas price is low. The heavy crude oil transportation also represents a challenge since the oil must be diluted in order to be accepted into pipeline transport.

[0034] The presented invention solves some of these problems. The transported heavy crude oil doesn't need to be diluted to usual 3:7 ratio (diluent: crude oil), it just needs to attain certain lower viscosity so it can be unloaded from the container using the diaphragm pressurized from the second compartment. A specialized pump, which utilizes electronic flow sensors, registers pumped crude oil composition and adjusts the injection of the chemicals accordingly. The crude oil cargo travels from source to a refinery usually quite few days. This time can be utilized for preconditioning of the crude oil according to the refinery needs. The container tank can be also equipped with optional tray on the bottom. This tray represents about 2.5% of the tank volume and is designed for aggregation of unwanted precipitate, which would stay there until the container tank returns to the point of origin. The tray is then washed out according to sediment level, using the loading pump system and a solvent.

[0035] There is enormous advantage hidden in a such system. The content of every batch represented by every single container tank, with capacity approx. 300 barrels, is described using above mentioned sensors in the loading pump flow lines, and thus there is possibility to construct a specific crude oil essay for every set of these batches. The container tanks are not limited just for heavy oil, they can be utilized for light oil as well as various condensates. It is possible to prepare complete refinery blends which can be blended in fly while being unloaded from a sea vessel directly into refinery charging tanks. Such designed system would skip many problematic refinery segments and crude oil blends preparation steps, such as dewatering, desalting, blending and chemical preconditioning.

[0036] The geolocational factor of the discount represents transportation costs. The production source of the Canadian bitumen is landlocked in the province of Alberta. The pipeline capacity has its limits, and crude oil producers and transporting companies are eager to find ways how to get the oil to the tidewaters. The other economically acceptable option, beside pipelines, is railway transport. Conventional tank car trains require loading and unloading stations, which are costly to build and maintain. While containerized oil transportation can be merged into existing flow of general cargo containers. It is a fact known to the ones skilled in the art, that container slots in intermodal trains are underutilized. In average, railway well cars are loaded to about 50% of their weight capacity (Pickel, 2015). The intermodal railway transportation is a special example of underutilization since, in North America, there is uneven flow of full containers from west to east coast and flow of empty containers the other way. In average 100 car train, there are always at least two locomotives, a rule independent of the train weight requirements. Higher tonnage per car would represent just some percentage higher fuel cost, since all other capital costs, equipment, manpower etc., are fixed per train. A five-well intermodal double stack flat car can carry ten containers. Allowed tonnage per each of the middle wells is about 55 tones and 70 tones at each end well. Such average multi-well railway car can carry, for example, four FEU tanks with bitumen weighting 50 tones, two FEU with general cargo 225 tones, another two empty FEUs 25 tones, and two 53 domestic reefers weighting 20 tones each. In this configuration, the rail car tonnage capacity would be almost fully utilized.

[0037] The same utilization problem exists in marine container transport. Just the costs are the same for both ways, since a steamship burns fuel hauling ballast water when traveling underutilized. Good example would be transport of bitumen from Alberta to Californian west coast refineries. The container is loaded at a production oil field in Athabasca region and travels on a truck trailer chassis to the nearest intermodal container yard near Fort McMurray. There the container is merged with other tank containers on an intermodal double stack train, travels to Edmonton to an intermodal container yard, is mixed with general cargo intermodal containers and is shipped to Vancouver. There is loaded onto a special RoRo (roll on roll off) steamship, which has container tank slots on the bottom under deck equipped with pumps. The RoRo steamship can also load general cargo containers above deck. With full container tanks of bitumen on the bottom, there would be still enough tonnage capacity to load above deck slots with empty general cargo containers. The steamship would travel to a California coast refinery, unload bitumen at a berth and load gasoline or any other refined products. The ship would stop at Long Beach seaport, unload empty general cargo containers located above deck, load full ones and travel back to Washington/B.C. coast. The refined products could be unloaded along the way at any suitable port or terminal. The full general cargo containers can be transferred at the same port as the empty tank containers onto an intermodal train and travel to Edmonton to an intermodal yard.

[0038] The primary goal of the whole logistic system is utilization of tonnage capacity and elimination of deadheading.

[0039] In the preceding description, for purposes of explanation, numerous details are mentioned in order to provide sufficient understanding of the embodiments of the invention. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the invention.

[0040] The above-described embodiments of the invention are intended to be examples only. Alterations, modifications and variations can be affected to the particular embodiments by those skilled in the art without departing from the scope of the invention, which is defined solely by