Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
CONTROLLABLE STEAM AND CO2 UNIT (CSCU)
Document Type and Number:
WIPO Patent Application WO/2018/223211
Kind Code:
A1
Abstract:
A controllable steam CO2 unit (CSCU) for generating steam and CO2 simultaneously within a combustion chamber is invented. High pressure fuel and high pressure oxidant are injected into the chamber for combustion. Meanwhile, high pressure water is injected into the spiral flow cooling annulus. The water reduces the temperature of the combustion chamber and absorbs the combustion heat. Eventually the water is sprayed into the chamber from star-shaped ports and then evaporates. The final products include steam, CO2, N2, and some liquid water, which are directly injected into a heavy oil reservoir. The CO2 can dissolve into heavy oil to reduce oil viscosity. The fuel can be diesel or natural gas or other option. The injected oxidant can be air or oxygen-enriched gases. CSCU operation is based on a programmable logic controller (PLC). The CSCU has high heat efficiency, low operating cost, and no surface greenhouse gas emissions.

Inventors:
REN YOUMIN (AU)
BAI YANG (CA)
LI PINGKE (CA)
Application Number:
PCT/CA2017/050699
Publication Date:
December 13, 2018
Filing Date:
June 08, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
CSCU PETROTECH CORP (CA)
International Classes:
F22B1/26; C01B32/50; E21B43/24
Foreign References:
US20030014959A12003-01-23
US20110036095A12011-02-17
US20100193188A12010-08-05
Attorney, Agent or Firm:
STIKEMAN ELLIOTT LLP et al. (CA)
Download PDF:
Claims:
CLAIMS

1) The controllable steam C02 unit (CSCU) for generating steam and C02 simultaneously within a combustion reactor comprising:

(a) combustion chamber;

(b) high pressure water supply system;

(c) high pressure fuel supply system;

(d) high pressure oxidant supply system;

(e) programmable logic controller (PLC).

The CSCU of claim 1 wherein the combustion chamber 1 (a) can be a cylinder or a cone or another optimized shape.

The CSCU of claim 1 wherein the combustion chamber 1 (a) has an inner sleeve and an outer confining shell.

The CSCU of claim 1 wherein the combustion chamber 1 (a) has entrance and exit ends. At the entrance end, there are three supply pipes connected to high pressure water supply system 1 (b), high pressure fuel supply system 1 (c), and high pressure oxidant supply system 1 (d), respectively; at the exit end, multiple thermal fluids, including steam, C02, N2, and a small amount of liquid water, flow to an injection well or to a buffer tank first, and then to an injection well.

The CSCU of claim 3 wherein a spiral flow cooling annulus exists between the inner sleeve and the outer confining shell. The spirally flowing water is sprayed into the combustion chamber 1 (a) through star-shaped spray ports. The star-shaped spray ports are designed based on optimized distribution pattern and evaporation efficiency. The CSCU of claims 1 and 5 wherein the input water 1 (b) is injected into the spiral flow cooling annulus between the inner sleeve and the outer confining shell.

The CSCU of claim 1 wherein the input fuel 1 (c) and input oxidant 1 (d) are directly injected into the combustion chamber.

The CSCU of claim 1 wherein the injected water 1 (b) must be treated to meet the

requirements designed for the CSCU.

The CSCU of claim 1 wherein the high pressure fuel 1 (c) can be diesel or natural gas or other optimized option.

The CSCU of claim 1 wherein the high pressure oxidant 1 (d) can be air or oxygen-enriched gases.

The CSCU of claim 1 wherein the PLC 1 (e) is applied to operate the CSCU automatically.

The CSCU of claims 1 (e), 6, and 7 wherein the water injection is started first, and then fuel and oxidant injections follow. This injection sequence is managed by PLC 1 (e).

The CSCU of claims 1 (b) and 6 wherein the water injection rate, pressure, and temperature are measured by a flow meter, a pressure sensor, and a temperature sensor, respectively, and then sent to the PLC 1 (e).

The CSCU of claims 1 (c) and 7 wherein the fuel injection rate, pressure, and temperature are measured by a flow meter, a pressure sensor, and a temperature sensor, respectively, and then sent to the PLC 1 (e).

The CSCU of claims 1 (d) and 7 wherein the oxidant injection rate, pressure, and

temperature are measured by a flow meter, a pressure sensor, and a temperature sensor, respectively, and then sent to the PLC 1 (e).

The CSCU of claims 1 (e), 13, 14, and 15 wherein the water, fuel, and oxidant injection rates, pressures, and temperatures data are processed by the PLC system and their proportions adjusted automatically to meet the designed criteria. When the designed criteria is met, the automatic ignition occurs inside the combustion chamber.

The CSCU of claims 1 and 5 wherein the combustion heat generated inside the combustion chamber is partially transferred to the water flowing inside the spiral flow cooling annulus through the heat conduction process. Meanwhile, the temperature of the combustion chamber is reduced due to this heat transfer. Eventually the pre-heated water is sprayed into the evaporation section of the combustion chamber through the spray ports.

The CSCU of claim 1 wherein the exit end has jet pipe with flow meter, pressure sensor, and temperature sensor to capture the outflow data, which are transferred to the PLC 1 (e).

When any abnormal signals or incident data are captured, the PLC 1 (e) will report and/or shut down the CSCU operation immediately according to pre-defined alert levels.

Description:
CONTROLLABLE STEAM AND C02 UNIT (CSCU)

FIELD OF THE INVENTION

[001] The invention of controllable steam and C0 2 unit (CSCU) relates to the recovery, extraction, and production of heavy oil and bitumen.

BACKGROUND

[002] Heavy oil and oil sands resources are gradually becoming an important fossil fuel and widely used in the world. A number of recovery processes have been investigated and applied for developing the heavy oil and bitumen resources, such as the those found in Canada, Venezuela, China, and the United States.

[003] Methods that have been developed include non-thermal processes and thermal processes. Non-thermal processes include natural pressure depletion, water flooding, polymer flooding, and gas injection. Thermal processes include cyclic steam stimulation (CSS), steam flooding, steam assisted gravity drainage (SAGD), and in-situ combustion. [004] Non-thermal recovery processes have their major disadvantages. Natural pressure depletion may have low recovery factor and production rate; water flooding and polymer flooding consume a large quantity of water with low production rates; gas injection has low recovery factor and rate with a high consumption of energy.

[005] Thermal recovery processes can improve the production rate significantly. However, the in- situ combustion process is difficult to control within the reservoir.

[006] SAGD, CSS, and steam flooding utilize the conventional steam generators, which emit huge amount of greenhouse gas into the atmosphere. Meanwhile, a large quantity of heat is released into the atmosphere with the air emission process.

[007] A need therefore exists for generating thermal fluids with less greenhouse gas emission and less heat loss to the atmosphere. A solution that addresses, at least in part, the above and the other shortcomings is desired. [008] Other known methods are described in patents and published patent applications such as US No. 2,734,578 to Walter, US No. 4,546,829 to Martin et al., and US No. 7,780,152 B2 to Rao. All of which are incorporated herein by reference. The general concept is that a group of thermal fluids, such as steam, N 2 , and C0 2 can be generated at the same time by the combustion process.

[009] Comparing with other patents, this invention utilizes a highly automatic control system to control, monitor, and adjust both input and output fluids. Also, it manages the overall combustion process and ensure the process is operated efficiently and safely. In addition, a strong refractory material is applied for the inner sleeve of the combustion chamber, which is also protected by a cooling annulus between the inner sleeve and the outer confining shell. A spiral water flow occurs inside the cooling annulus. Another key design is the optimized distribution pattern of the water spray ports around the evaporation section of the combustion chamber.

SUMMARY OF THE INVENTION

[0010] The invention is related to a method of generating multiple thermal fluids, including steam, C0 2 , N 2 , and a small amount of liquid water, through a high pressure and high temperature combustion reactor.

[0011] The core structure of the reactor includes the entrance end of input fluids, the combustion chamber, and the spiral flow cooling annulus between the inner sleeve and the outer confining shell, exit end for output fluids, and jet pipe. Other key components include igniter, fuel nozzle, oxidant nozzle, inner sleeve with spiral threads and star-shaped water spray ports around the evaporation chamber, outer confining shell, and the high pressure seal of the combustion chamber.

[0012] According to another embodiment of the invention, the fuel injection pipe, which is connected to the high pressure fuel supply system, directly injects the optimized fuel into the combustion chamber. [0013] According to another embodiment of the invention, the oxidant injection pipe, which is connected to the high pressure oxidant supply system, directly injects the optimized oxidant into the combustion chamber.

[0014] According to one aspect of the invention, the water injection pipe, which is connected to the high pressure water supply system, directly injects the water into the spiral flow cooling annulus between the inner sleeve and the outer confining shell. When combustion occurs inside the combustion chamber, the spiral flow style of the injected water not only cools the temperature of the combustion chamber, but also absorbs the combustion heat through the conduction process.

[0015] According to another embodiment of the invention, the water flowing inside the cooling annulus is sprayed into the evaporation section of the combustion chamber through pre-designed star-shaped injection ports.

[0016] According to another embodiment of the invention, at least one pressure sensor, at least one temperature sensor, and at least one flow meter are installed on the fuel injection pipe before the fuel is injected into the combustion chamber.

[0017] According to another embodiment of the invention, at least one pressure sensor, at least one temperature sensor, and at least one flow meter are installed on the oxidant injection pipe before the oxidant is injected into the combustion chamber.

[0018] According to another embodiment of the invention, at least one pressure sensor, at least one temperature sensor, and at least one flow meter are installed on the water injection pipe before water is injected into the spiral flow cooling annulus. [0019] According to another embodiment of the invention, at least one pressure sensor, at least one temperature sensor, and at least one flow meter are installed on the jet pipe where multiple thermal fluids (steam, N2, C02, and a small amount of liquid water) flow out of the evaporation section of the combustion chamber.

[0020] All the high pressure, high temperature, and flow rate data recorded through [0016] to [0019] are sent to a programmable logic controller (PLC).

[0021] According to another embodiment of the invention, the ignition of the igniter installed at the fluids entrance end is also controlled by the PLC.

[0022] According to another embodiment of the invention, water injection to the spiral flow cooling annulus is started first and then, fuel and oxidant injection to the combustion chamber follows. [0023] According to another embodiment of the invention, when the fuel and oxidant injection rates meet the designed combustion criteria, the ignition process is started. [0024] According to another embodiment of the invention, the fluids injection sequence, rates, and ignition process are all controlled by the PLC.

[0025] According to another embodiment of the invention, the entire operation process of the CSCU 85 is monitored by the PLC.

[0026] According to another embodiment of the invention, any abnormal issues occurring during the CSCU operation will be reported automatically by the PLC. When serious and high risk incident happens, the CSCU operation will be shut down immediately.

BRIEF DESCRIPTION OF THE DRAWINGS

90 [0027] For a further understanding of the nature and objects of the present invention, reference should be made to the following detailed description, taken in combination with the accompanying drawings, in which:

[0028] FIG. 1 is illustrating the major related components of the CSCU; and

[0029] FIG. 2 is illustrating the major working mechanism of the CSCU according to an

95 embodiment of the invention; and

[0030] FIG. 3 is an overall view illustrating the additional equipment, such as pressure transducers, temperature transducers, flow meters, valves, nozzles, and motors, associated with the combustion reactor;

[0031] In the description which follows, like parts are marked throughout the specification and the 100 drawings with the same respective reference numerals.

DETAILED DESCRIPTION OF THE EMBODIMNETS

[0032] The description which follows and the embodiments described therein are provided by way of illustration of an example or examples of particular embodiments of the principles of the present invention. There examples are provided for the purposes of explanation and not limitation of these 105 principles and of the invention. In some instances, certain structures and techniques have not been described or shown in detail in order not to obscure the invention. [0033] As part of this patent application, a number of terms are being used in accordance with what is understood to be the ordinary meetings of these terms. For instance, "fluid" includes both liquids and gases. [0034] Figure 1 is illustrating the major related components of the CSCU. The water supply system 10 provides the softened water to the combustion reactor 100. The fuel system 20 provides fuel (compressed natural gas or liquid fuel), and the oxidant system 30 provides compressed air or other oxygen-enriched oxidant to the combustion reactor 100. The generated multiple thermal fluids, such as steam, C0 2 , N 2 , and a small amount of liquid water, are sent to a container 300 (such as a buffer tank) or directly injected into an injection well.

[0035] Figure 2 is illustrating the detailed working process of the CSCU. When the CSCU operation is started, the water supply system 10 preferentially provides the softened water to the spiral flow cooling annulus 50 between the inner sleeve 70 and the outer confining shell 75. Then, the fuel supply system 20 and oxidant supply system 30 provide fuel and oxidant, respectively, to the combustion chamber 100. The proportional injection rates of water, fuel, and oxidant are predesigned based on the expected steam quality. When the injected rates meet the designed criteria, igniter 40 will start to set fire inside the combustion chamber. Over the combustion process, the injected water spirally flows inside the cooling annulus along the screw thread 60 between the inner sleeve and the outer confining shell. The water spiral flow plays two important roles. One is to cool the temperature inside the combustion chamber and the other is to absorb the heat transferred to the water through thermal conduction. Eventually the water is sprayed into the combustion chamber through star-shaped injection ports 80 and evaporate immediately. The space between the water spray ports and the exit end is the evaporation section of the combustion chamber. Through the jet pipe at the exit end, multiple thermal fluids 90, including steam, N 2 , C0 2 , and a small amount of liquid water, flow to an injection well, or to a buffer tank first and then to an injection well.

[0036] For the entire working process of the CSCU, the proportional injection rates, injection pressures, and temperatures of water, fuel, and oxidant are all controlled, monitored, and adjusted by the PLC. The temperature of the spiral flow cooling annulus, exit rates, exit pressures, and exit temperatures of the generated thermal fluids are also monitored by the PLC. When any abnormal events or incidents occurs, the PLC will report or even shut down the combustion reactor immediately based on pre-defined alarm levels.

[0037] Figure 3 is an overall view showing additional equipment associated with the combustion reactor, which can be listed as follows.

[0038] 1 - temperature transducer of input water; 2 - adjusting valve of input water; 3 - varying frequency water pump with high pressure; 4 - motor for water pump; 5 - first switch for water pressure transducer; 6 - first water pressure transducer; 7 - water filter; 8 - water flow meter; 9 - second switch for water pressure transducer; 11 - second water pressure transducer; 12 - check valve for water.

[0039] 13 - temperature transducer of input fuel; 14 - adjusting valve of input fuel; 15 - varying frequency fuel pump with high pressure; 16 - motor for fuel pump; 17 - first switch for fuel pressure transducer; 18 - first fuel pressure transducer; 19 - fuel filter; 21 - fuel flow meter; 22 - second switch for fuel pressure transducer; 23 - second fuel pressure transducer; 24 - check valve for fuel.

[0040] 25 - temperature transducer of input air; 26 - first adjusting valve of input air; 27 - second adjusting valve of input air; 28 - air flow meter; 29 - switch for air pressure transducer; 31 - air pressure transducer; 32 - check valve for air.

[0041] 33 - temperature transducer for spiral flow cooling annulus.

[0042] 34 - switch for pressure transducer of multiple thermal fluids; 35 - pressure transducer of multiple thermal fluids; 36 - temperature transducer of multiple thermal fluids; 37 - first safety valve for multiple thermal fluids; 38 - ventilation valve; 39 - first nozzle; 41 - second nozzle; 42 - check valve for multiple thermal fluids; 43 - close valve for multiple thermal fluids.

[0043] 100 - combustion reactor.