Flow-limiting normal-pressure hot water and heat exchange system with large-diameter heat exchange tubes and control method thereof
Technical Field
The invention relates to the technical field of heat exchange equipment, in particular to a flow-limiting normal-pressure hot water and heat exchange system with a large-diameter heat exchange tube and a control method thereof.
Background
After petroleum is pumped out of the oil well, the petroleum needs to be heated at the well head due to the long-distance transportation when encountering condensation solidification. At present, the method is mainly realized by adopting an electric heating strip, electromagnetic induction and an air source heat pump electric heating method, and a large amount of electric energy needs to be consumed. The oil well is often accompanied by the generation of natural gas in the oil extraction process, and the associated gas has no recovery value and is generally treated by adopting a wellhead emptying or burning mode, thereby wasting resources and polluting the environment. The associated gas is comprehensively utilized to replace electric heating to heat the crude oil, so that electric energy can be effectively saved, pollution caused by natural gas evacuation can be reduced, and the method is the most reasonable selection and development direction of the oil well crude oil heating technology.
The existing associated gas crude oil heating system adopts a structure as shown in figure 1, heats water in a hot water chamber (or a boiler) by burning associated gas, then sends hot water or steam into a heat exchange pipe of a tubular heat exchanger, and exchanges heat with crude oil flowing through the outside of the heat exchange pipe through heat conduction of the wall of the heat exchange pipe for heating. The structure has the following problems for field application of associated gas crude oil heating equipment with medium and small power and heat exchange quantity lower than 150 KW:
1. if hot water type heat exchange is adopted, the heat exchange tubes of the tube type heat exchanger are parallel, the number of the heat exchange tubes needs to be increased or the diameter of the heat exchange tubes needs to be increased in order to ensure the heat exchange area, so that the total cross section of water flowing is relatively large, hot water with enough flow needs to be provided for the heat exchanger in order to ensure that hot water passes through each heat exchange tube, and water is supplied to each heat exchange tube by a water inlet chamber in a positive pressure mode, so that the flow of a required water supply pump of a hot water chamber is too large, and the technology is difficult to realize;
2. if the steam type heat exchange is adopted, the high-power heat exchange requirement can be met without a water supply circulating pump, but the steam heating of the closed boiler has potential safety hazard and does not meet the normal pressure requirement of oil field operation;
3. the split structure of hot water and heat exchange leads the volume of the hot water and heat exchange system to be relatively increased, and the technical indexes and performance requirements of small volume and high power cannot be met;
4. the existing associated gas import crude oil heating equipment only has a single function of gas heating, is only suitable for oil wells with associated gas yield enough to meet the heating requirement of import crude oil, and the associated gas generated by the oil wells with insufficient associated gas yield can not be utilized and can only be emptied.
The technical problems restrict the popularization and the application of the associated gas crude oil heating system. So far, only a small amount of associated gas crude oil heating systems are applied to oil fields in Jiangsu province, and other main oil fields in China such as Daqing still adopt electric heating, so that the development of a novel crude oil heating system is necessary.
Disclosure of Invention
The invention aims to provide a flow-limiting normal-pressure hot water and heat exchange system with a large-diameter heat exchange tube and a control method thereof, and aims to solve the technical problems.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the invention provides a flow-limiting normal-pressure hot water and heat exchange system with a large-diameter heat exchange tube, which comprises:
the hot water tank is internally divided into a hot water chamber, a heat exchange chamber and a water diversion chamber which are sequentially arranged from bottom to top by a lower partition plate and an upper partition plate which are horizontally arranged, a hot water chamber water outlet and a hot water chamber water inlet are arranged below the hot water chamber, the water diversion chamber is provided with a water diversion chamber water inlet, and the hot water chamber water outlet is communicated with the water diversion chamber water inlet through a pipeline and a circulating pump;
the heat exchange tube, the vertical setting of a plurality of the heat exchange tube is arranged in the heat exchange chamber, go up on baffle and the lower baffle seted up with heat exchange tube assorted through-hole, the through-hole with join in marriage dress the heat exchange tube parallel and level is sealed, heat exchange tube outer pipe wall with go up baffle, lower baffle and hot-water tank inner wall cooperation formation heat transfer chamber, heat transfer chamber outer wall bottom and top be equipped with respectively with cold liquid import and hydrothermal solution export of heat transfer chamber intercommunication, the heat exchange tube bottom is equipped with the shrouding, the restricted aperture has been seted up on the shrouding.
By adopting the scheme, water in the hot water chamber is heated by the associated gas combustion system below, then is sent to the water distribution chamber through the circulating pump, enters the heat exchange tube from the water distribution chamber, returns to the hot water chamber through the flow limiting hole at the bottom of the heat exchange tube for circulation, and forms a reverse heat exchange process with crude oil which enters from the outside of the heat exchange tube from bottom to top;
by selecting a circulating pump with the reasonable total cross section area of the flow limiting holes and the flow pressure matched with the flow pressure, the positive pressure full water backflow circulating heat exchange of each heat exchange tube under the condition of low-flow water supply can be realized;
the bottom end of the heat exchange tube is sealed by a sealing plate with a flow limiting hole, so that the tube diameter of the heat exchange tube and the water flux in the heat exchange tube are independent parameters which are not related to each other, the heat exchange area can be reasonably increased by adopting the large-diameter heat exchange tube, and the heat exchange tube is easy to manufacture; the area of the flow limiting holes of each heat exchange tube can be distributed according to the total area proportion of the flow limiting holes, so that the heat exchange power optimization configuration of heat exchange in the heat exchange chamber is realized, and higher heat exchange efficiency is obtained.
Furthermore, the hot water tank further comprises a smoke exhaust pipe, wherein the smoke exhaust pipe is vertically arranged inside the heat exchange pipe, and two ends of the smoke exhaust pipe extend out of the bottom and the top of the hot water tank respectively.
By adopting the above scheme, the flue gas that hot water produced is discharged through discharging fume to hot water chamber below burning associated gas heating, and the flue gas carries out high-efficient interior heating to the water in hot water chamber, heat exchange tube and the water diversion chamber in proper order when discharging fume the pipe simultaneously, further improves efficiency and heating efficiency.
Furthermore, the steam pipe is vertically arranged inside the heat exchange pipe, the bottom end of the steam pipe extends to be communicated with the hot water chamber, the top end of the steam pipe penetrates out of the top of the hot water tank through the water distribution chamber, and the bottom end of the steam pipe is flush with the lower partition plate.
By adopting the scheme, the circulating pump continuously transmits the hot water to the water distribution chamber, so that the water distribution chamber is in a relative positive pressure state relative to the hot water chamber, and all steam is pressed on the top surface of the hot water chamber and is discharged through the steam pipe, thereby ensuring that the hot water chamber is heated at normal pressure; meanwhile, the steam heats the heat exchange pipe and the water in the water diversion chamber in the steam pipe, so that the energy efficiency and the heating efficiency are further improved.
Furthermore, the steam pipe is arranged in the heat exchange pipe in the center of the heat exchange chamber, and the smoke exhaust pipes and the rest heat exchange pipes are arranged in the heat exchange pipes in a one-to-one correspondence manner.
By adopting the scheme, the steam pipe at the central position is beneficial to the quick and efficient discharge of steam; the heat exchange pipes in the center are removed, and smoke exhaust pipes are arranged in the rest of the heat exchange pipes so as to meet the requirements of smooth smoke exhaust of the combustor and effective absorption of scattered heat energy of the smoke.
Furthermore, the circumferential surfaces of the steam pipe and the smoke exhaust pipe are uniformly sleeved and fixed with flow deflectors at intervals along the axial direction, and the flow deflectors are arranged in the heat exchange pipe and remain gaps between the flow deflectors and the inner wall of the heat exchange pipe for guiding hot water to the inner wall of the heat exchange pipe.
Through adopting above-mentioned scheme, the water conservancy diversion piece sets up at the steam pipe with discharge fume the pipe global, consequently hot water that from top to bottom flows can be shunted to all around by the water conservancy diversion piece for hot water and heat exchange tube pipe wall contact heat transfer better, realize the high-efficient heat transfer of heavy-calibre heat exchange tube, also can carry out more efficient internal heating through the water conservancy diversion piece in discharging fume simultaneously.
The steam heating device is characterized by further comprising a water tank, wherein a steam feeding port and a water filling port are arranged at the top of the water tank, a water tank water outlet is arranged at the bottom of the water tank, the water tank water outlet is higher than the lower partition plate, the water tank water outlet is communicated with the water inlet of the hot water chamber through a pipeline, the steam feeding port is communicated with the top end of the steam pipe through a pipeline, and the top end of the water tank is lower than the lower end of the water inlet of the water distribution chamber.
By adopting the scheme, the water outlet of the water tank is higher than the lower partition plate at the top of the hot water chamber, so that the water tank can automatically replenish full water in the hot water chamber; meanwhile, the water tank absorbs the steam discharged by the steam pipe, so that the heat waste is reduced, and the normal-pressure safe full-water heating of the hot water chamber is ensured;
the top end of the water tank is lower than the water inlet of the water diversion chamber, so that water is prevented from overflowing from the water inlet of the water diversion chamber through the flow limiting hole in the disassembly process of the circulating pump.
Furthermore, the top of the water distribution chamber is also provided with an air outlet, the top of the water tank is provided with an air-water feeding inlet, and the air outlet is communicated with the air-water feeding inlet through a pipeline.
Through adopting above-mentioned scheme, the gas vent is used for heat exchange box inside air under the initial condition to discharge.
Furthermore, the aperture of the exhaust port is matched with that of the flow limiting hole;
by adopting the scheme, the hot water with the single flow limiting hole flow is sent into the water tank through the exhaust hole in real time when the equipment runs, and the hot water is used for preventing freezing in winter.
The water heater is characterized by further comprising an electromagnetic induction heating pipe, wherein the electromagnetic induction heating pipe is arranged outside the hot water tank, a water inlet at the bottom end of the electromagnetic induction heating pipe is connected with a water outlet of the circulating pump through a pipeline, and a water outlet at the top end of the electromagnetic induction heating pipe is connected with a water inlet of the water distribution chamber through a pipeline.
By adopting the scheme, water in the hot water chamber can be pumped out by the circulating pump, is sent to the water distribution chamber through the electromagnetic induction heating pipe, starts the electromagnetic induction heating function, and then realizes the fuel gas and electromagnetic induction combined heating of the hot water and the heat exchange system.
Electromagnetic induction heating is the most advanced heating technology at present, the electric-heat conversion efficiency of the non-conduction heating is as high as more than 95%, the power adjustment and the heating response speed are extremely high, and the non-conduction heating is the best heat source which can be compounded with gas heating at present.
The existing associated gas wellhead crude oil heating equipment only has a single function of gas heating, and is only suitable for oil wells with associated gas yield enough to meet the requirement of wellhead crude oil heating, and the associated gas generated by the oil wells with insufficient associated gas yield cannot be utilized and can only be emptied.
The hot water and heat exchange system adopts the combined heating of the associated gas and the electromagnetic induction, and when the yield of the associated gas at a wellhead is insufficient, the associated gas is supplemented by the electromagnetic induction heating, so that the associated gas of an oil well with insufficient yield of the associated gas can be fully utilized, and the economic and social efficiency is important.
Furthermore, temperature sensors are arranged at the water outlet of the electromagnetic induction heating pipe and the hot liquid outlet of the heat exchange chamber.
By adopting the scheme, the temperature of the water outlet of the electromagnetic induction heating pipe, namely the water inlet temperature of the water distribution chamber and the hot liquid outlet temperature of the heat exchange chamber can be acquired in real time.
The invention discloses a control method of the flow-limiting normal-pressure hot water and heat exchange system of the large-diameter heat exchange tube in the second aspect, which comprises starting control and circulation control;
the starting-up control comprises the following steps:
s1 presetting the water outlet temperature T of the electromagnetic induction heating pipe Water facilities And a hot liquid outlet temperature T of the heat exchange chamber Oil device And when the temperature of the water outlet of the electromagnetic induction heating pipe is T Water facilities When the temperature of the hot liquid outlet of the heat exchange chamber is more than or equal to T Oil device ;
S2, after the starting-up work is stable, detecting the electromagnetic inductionWater outlet temperature T of heat pipe Water inlet And a hot liquid outlet temperature T of said heat exchange chamber Oil outlet When T is Oil outlet ≥T Oil device When the electromagnetic induction heating pipe does not work, the electromagnetic induction heating pipe is controlled to work as T Oil outlet <T Oil device When the control is started, the circulation control is started;
the circulation control comprises the following steps:
s1' controlling the electromagnetic induction heating pipe to start and power
Wherein L is the flow rate of the circulating pump;
s2' after the electromagnetic induction heating pipe is started, the temperature T of the water outlet of the electromagnetic induction heating pipe is detected at regular intervals Water inlet And a hot liquid outlet temperature T of said heat exchange chamber Oil outlet ;
When T is
Oil outlet <T
Oil device While controlling the power of the electromagnetic induction heating pipe
When T is Oil device +10℃≥T Oil outlet ≥T Oil device When the electromagnetic induction heating pipe is used, the power of the electromagnetic induction heating pipe is kept unchanged;
when T is Oil outlet >T Oil device And controlling the power of the electromagnetic induction heating pipe to be reduced by 2kw at the temperature of +10 ℃.
By adopting the scheme, after the startup control is used for the system startup work stability, whether the yield of the associated gas is enough for heating is judged, and if T, the output of the associated gas is enough for heating Oil outlet ≥T Oil device Indicating that the yield of associated gas is enough, and the electromagnetic induction heating pipe can not be started, if T Oil outlet <T Oil device If the yield of the associated gas is insufficient, the electromagnetic induction heating pipe needs to be started through circulation control to carry out auxiliary heating.
The circulation control is firstly carried out according to the temperature difference T between the set temperature and the actual detection temperature of the water inlet of the water distribution chamber Water facilities -T Water inlet To set the power; then detecting the temperature at intervals, andadjusting power according to the detection result, and adjusting T Oil outlet Is controlled at T Oil device ~T Oil device Within a range of +10 ℃.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the invention, the partition of the partition plate in the hot water tank and the sleeving of the smoke exhaust pipe and the heat exchange pipe are adopted, so that the integration of hot water and heat exchange is realized, and the volume is miniaturized;
2. the bottom end of the heat exchange tube is sealed by the sealing plate with the flow limiting hole, so that the tube diameter of the heat exchange tube and the water flux of the heat exchange tube are independent parameters which are not related to each other, and the heat exchange area of the heat exchange tube can be reasonably increased by increasing the tube diameter of the heat exchange tube;
3. according to the invention, the total area of the flow limiting holes of the heat exchange tubes matched with the flow and the pressure of the circulating pump and the area of the flow limiting holes distributed in proportion of each heat exchange tube are selected, so that the water pumped out of the hot water chamber is distributed in proportion of the area of the flow limiting holes of each heat exchange tube, and the water is filled with the water and subjected to positive pressure backflow heat exchange; by controlling the area of the flow limiting holes distributed in proportion to each heat exchange tube, the optimal configuration of heat exchange power in the heat exchange chamber is realized, and the heat exchange energy efficiency is further improved;
4. the hot water and heat exchange system adopts the combination heating of the associated gas and the electromagnetic induction, and when the yield of the associated gas at the wellhead is insufficient, the combined heating is supplemented by the electromagnetic induction, so that the associated gas of an oil well with insufficient yield of the associated gas can be fully utilized, and the economic efficiency and the social efficiency are important.
Drawings
In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
Fig. 1 is a schematic structural view of embodiment 1 of the present invention.
Fig. 2 is a schematic structural diagram of embodiment 2 of the present invention.
Shown in the figure:
1. a hot water tank;
2. a lower partition plate;
3. an upper partition plate;
4. a hot water chamber; 401. a water outlet of the hot water chamber; 402. a water inlet of the hot water chamber;
5. a heat exchange chamber;
6. a water diversion chamber; 601. a water inlet of the water diversion chamber; 602. an exhaust port;
7. a circulation pump;
8. a heat exchange pipe;
9. closing plates; 901. a flow restriction orifice;
10. a smoke exhaust pipe;
11. a steam pipe;
12. a flow deflector;
13. a water tank; 1301. a steam inlet; 1302. a water injection port; 1303. a water outlet of the water tank; 1304. gas and water are fed into the inlet;
14. a heat exchange cavity; 1401. a cold liquid inlet; 1402. a hot liquid outlet;
15. an electromagnetic induction heating pipe.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.
Example 1:
as shown in fig. 1, the embodiment provides a flow-limiting normal-pressure hot water and heat exchange system with a large-diameter heat exchange tube 8, which includes a hot water tank 1 and the heat exchange tube 8.
The hot water tank 1 is internally divided into a hot water chamber 4, a heat exchange chamber 5 and a water diversion chamber 6 which are sequentially arranged from bottom to top by a lower partition plate 2 and an upper partition plate 3 which are horizontally arranged, a hot water chamber water outlet 401 and a hot water chamber water inlet 402 are arranged below the hot water chamber 4, the water diversion chamber 6 is provided with a water diversion chamber water inlet 601, and the hot water chamber water outlet 401 is communicated with the water diversion chamber water inlet 601 through a pipeline and a circulating pump 7.
Wherein, the height of the hot water chamber 4 is 400mm, the height of the heat exchange chamber 5 is 600mm, and the height of the water dividing chamber 6 is 100mm.
Inside arranging of heat transfer chamber 5 has 9 heat exchange tubes 8 altogether 3, and heat exchange tube 8 is the vertical heavy-calibre pipe that sets up bore 160mm, and go up and set up on baffle 3 and the lower baffle 2 with 8 assorted through-holes of heat exchange tube, 8 parallel and level welding seams of heat exchange tube of through-hole and dress.
The outer wall of the heat exchange tube 8 is matched with the inner walls of the upper partition plate 3, the lower partition plate 2 and the hot water tank 1 to form a heat exchange cavity 14, the bottom and the top of the outer wall of the heat exchange chamber 5 are respectively provided with a cold liquid inlet 1401 and a hot liquid outlet 1402 which are communicated with the heat exchange cavity 14, the bottom end of the heat exchange tube 8 is provided with a sealing plate 9, the sealing plate 9 is provided with a flow limiting hole 901, and the aperture of the flow limiting hole 901 is 5mm.
The water in the hot water chamber 4 is heated by the associated gas combustion system below, then is sent to the water distribution chamber 6 through the circulating pump 7, enters the heat exchange tube 8 from the water distribution chamber 6, returns to the hot water chamber 4 through the flow limiting hole 901 at the bottom of the heat exchange tube for circulation, and forms a reverse heat exchange process with the crude oil which enters from the outside of the heat exchange tube 8 from bottom to top;
by selecting a reasonable circulation pump 7 with the total cross section area of the flow limiting holes 901 and the flow pressure matched with the total cross section area and the flow pressure, positive pressure full water backflow circulation heat exchange of each heat exchange tube 8 under the low-flow water supply condition can be realized;
the bottom end of the heat exchange tube 8 is sealed by a sealing plate 9 with a flow limiting hole 901, so that the tube diameter of the heat exchange tube 8 and the water flux in the heat exchange tube 8 are independent parameters which are not related to each other, the heat exchange area can be reasonably increased by adopting the large-diameter heat exchange tube 8, and the manufacturing is easy; the area of the flow limiting holes 901 of the heat exchange tubes 8 can be distributed according to the total area proportion of the flow limiting holes 901, so that the optimal configuration of the heat exchange power of heat exchange in the heat exchange chamber 5 is realized, and higher heat exchange efficiency is obtained.
The heat exchange box is also internally provided with 8 smoke exhaust pipes 10 and a steam pipe 11. The vertical setting of pipe 10 of discharging fume is inside heat exchange tube 8, and the pipe 10 both ends of discharging fume extend respectively and wear out the bottom and the top of hot-water tank 1, and the flue gas that hot-water chamber 4 below burning associated gas heating hot water produced is discharged through pipe 10 of discharging fume, and the flue gas carries out high-efficient internal heating to the water in hot-water chamber 4, heat exchange tube 8 and the diversion chamber 6 in proper order when the pipe 10 of discharging fume simultaneously, further improves efficiency and heating efficiency.
The steam pipe 11 is vertically arranged inside the heat exchange pipe 8, the bottom end of the steam pipe 11 extends to be communicated with the hot water chamber 4, the top end of the steam pipe penetrates out of the top of the hot water tank 1 through the water distribution chamber 6, and the bottom end of the steam pipe 11 is flush with the lower partition plate 2.
Because the circulating pump 7 continuously transmits the hot water to the water distribution chamber 6, the water distribution chamber 6 is in a relative positive pressure state relative to the hot water chamber 4, and the steam is completely pressed on the top surface of the hot water chamber 4 and is discharged through the steam pipe 11, so that the normal-pressure heating of the hot water chamber 4 is ensured; meanwhile, the steam heats the water in the heat exchange pipe 8 and the water distribution chamber 6 in the steam pipe 11, so that the energy efficiency and the heating efficiency are further improved.
The steam pipes 11 are arranged inside the heat exchange pipes 8 in the center of the heat exchange chamber 5, and the eight smoke discharge pipes 10 and the rest of the heat exchange pipes 8 are arranged inside the heat exchange pipes 8 in a one-to-one correspondence manner.
The steam pipe 11 at the central position is beneficial to quickly and efficiently discharging steam; the heat exchange tubes 8 at the center are removed, and the smoke exhaust tubes 10 are arranged in the other heat exchange tubes 8 so as to meet the requirements of smooth smoke exhaust of the combustor and effective absorption of scattered heat energy of the smoke.
Flow deflectors 12 are uniformly sleeved and fixed on the circumferential surfaces of the steam pipe 11 and the smoke exhaust pipe 10 at intervals along the axial direction, and the flow deflectors 12 are arranged inside the heat exchange pipe 8 and used for guiding hot water towards the inner wall of the heat exchange pipe 8.
The flow deflectors 12 are arranged on the circumferential surfaces of the steam pipe 11 and the smoke exhaust pipe 10, so that hot water flowing from top to bottom can be guided and distributed to the periphery by the flow deflectors 12, the hot water and the pipe wall of the heat exchange pipe 8 can be in contact with each other better for heat exchange, the high-efficiency heat exchange of the large-diameter heat exchange pipe 8 is realized, and meanwhile, more efficient internal heating can be carried out through the flow deflectors 12 in smoke exhaust.
The hot water tank 1 is also provided with a water tank 13, the top of the water tank 13 is provided with a steam feeding port 1301 and a water filling port 1302, the bottom of the water tank is provided with a water tank water outlet 1303, the water tank water outlet 1303 is higher than the lower partition plate 2, the water tank water outlet 1303 is communicated with the hot water chamber water inlet 402 through a pipeline, the steam feeding port 1301 is communicated with the top end of the steam pipe 11 through a pipeline, and the top end of the water tank 13 is lower than the lower end of the water dividing chamber water inlet 601.
The water outlet 1303 of the water tank is higher than the lower partition plate 2 at the top of the hot water chamber 4, so that the water tank 13 can automatically replenish the full water of the hot water chamber 4; meanwhile, the water tank 13 absorbs the steam discharged by the steam pipe 11, thereby reducing the heat waste and ensuring that the hot water chamber 4 is safely filled with water and heated at normal pressure;
the top end of the water tank 13 is lower than the water inlet 601 of the water diversion chamber, so that the water is prevented from overflowing from the water inlet 601 of the water diversion chamber through the flow limiting hole 901 in the disassembly process of the circulating pump 7.
The top of the water diversion chamber 6 is also provided with an exhaust port 602, the top of the water tank 13 is provided with a gas-water feeding port 1304, the exhaust port 602 is communicated with the gas-water feeding port 1304 through a pipeline, and the exhaust port 602 is used for exhausting air in the heat exchange box in an initial state.
The aperture of the exhaust port 602 is 5mm, the exhaust port is matched with the flow limiting hole 901, and hot water with the flow of the single flow limiting hole 901 is sent to the water tank 13 through the exhaust hole in real time when the equipment runs, so that the equipment is used for preventing freezing in winter.
In the embodiment, the hot water tank 1 is internally partitioned by the partition plate, the smoke exhaust pipe 10 is sleeved with the heat exchange pipe 8, so that hot water and heat exchange are integrated, and the volume is miniaturized;
in the embodiment, the bottom end of the heat exchange tube 8 is sealed by the sealing plate 9 with the flow limiting hole 901, so that the tube diameter of the heat exchange tube 8 and the water flux of the heat exchange tube are independent parameters which are selected independently, and the heat exchange area can be increased reasonably by increasing the diameter of the heat exchange tube 8;
in the embodiment, the total area of the throttling holes 901 of the heat exchange tubes 8, which is matched with the flow and pressure of the circulating pump 7, and the area of the throttling holes 901 distributed in proportion of each heat exchange tube 8 are selected, so that the water pumped out of the hot water chamber 4 is distributed in proportion of the area of the throttling holes 901 of each heat exchange tube 8, and the water is filled with the water for positive pressure backflow heat exchange; by controlling the area of the flow limiting holes 901 distributed in proportion to each heat exchange tube 8, the optimal configuration of heat exchange power in the heat exchange chamber 5 is realized, and the heat exchange energy efficiency is further improved.
Example 2:
the structure of the present embodiment is basically the same as that of embodiment 1, except that an electromagnetic induction heating pipe 15 is further disposed outside the hot water tank 1 of the present embodiment.
The water inlet at the bottom end of the electromagnetic induction heating pipe 15 is connected with the water outlet of the circulating pump 7 through a pipeline, and the water outlet at the top end of the electromagnetic induction heating pipe 15 is connected with the water inlet 601 of the water diversion chamber through a pipeline.
The water in the hot water chamber 4 can be pumped out by the circulating pump 7 and is sent to the water distribution chamber 6 through the electromagnetic induction heating pipe 15, and the electromagnetic induction heating function is started, so that the gas and electromagnetic induction combined heating of the hot water and the heat exchange system is realized.
Electromagnetic induction heating is the most advanced heating technology at present, the electric-thermal conversion efficiency of the non-conduction heating is as high as more than 95%, the power adjustment and the heating response speed are extremely high, and the non-conduction heating is the best heat source which can be compounded with gas heating at present.
The existing associated gas wellhead crude oil heating equipment only has a single function of gas heating, and is only suitable for oil wells with associated gas yield enough to meet the requirement of wellhead crude oil heating, and the associated gas generated by the oil wells with insufficient associated gas yield cannot be utilized and can only be emptied.
The hot water and heat exchange system adopts the combination heating of the associated gas and the electromagnetic induction, and when the yield of the associated gas at the wellhead is insufficient, the combined heating is supplemented by the electromagnetic induction, so that the associated gas of an oil well with insufficient yield of the associated gas can be fully utilized, and the economic efficiency and the social efficiency are important.
Temperature sensors are arranged at the water outlet of the electromagnetic induction heating pipe 15 and the hot liquid outlet 1402 of the heat exchange chamber 5, and the temperature of the water outlet of the electromagnetic induction heating pipe 15, namely the water inlet temperature of the water distribution chamber 6, and the temperature of the hot liquid outlet 1402 of the heat exchange chamber 5 can be acquired in real time.
The embodiment also provides a control method of the flow-limiting normal-pressure hot water and heat exchange system with the large-diameter heat exchange tube 8, which comprises starting control and circulation control.
The startup control comprises the following steps:
s1 presetting the water outlet temperature T of the electromagnetic induction heating pipe 15 Water facilities And hot liquid outlet 1402 temperature T of heat exchange chamber 5 Oil device And when the temperature of the water outlet of the electromagnetic induction heating pipe 15 is T Water facilities Meanwhile, the temperature of the hot liquid outlet 1402 of the heat exchange chamber 5 is more than or equal to T Oil device ;
S2, after the starting-up operation is stable, detecting the water outlet temperature T of the electromagnetic induction heating pipe 15 Water inlet And hot liquid outlet 1402 temperature T of heat exchange chamber 5 Oil outlet When T is Oil outlet ≥T Oil device When the electromagnetic induction heating pipe 15 does not work, the electromagnetic induction heating pipe is controlled to work when T Oil outlet <T Oil device When the control is finished, starting cycle control;
the circulation control comprises the following steps:
s1' controls the starting of the electromagnetic
induction heating pipe 15, and the power
Wherein L is the flow rate of the circulation pump 7;
s2' after the electromagnetic induction heating pipe 15 is started, the water outlet temperature T of the electromagnetic induction heating pipe 15 is detected every 2min Water inlet And hot liquid outlet 1402 temperature T of heat exchange chamber 5 Oil outlet ;
When T is
Oil outlet <T
Oil device While controlling the power of the electromagnetic
induction heating pipe 15
When T is Oil device +10℃≥T Oil outlet ≥T Oil device When the power of the electromagnetic induction heating pipe 15 is kept unchanged;
when T is Oil outlet >T Oil device And when the temperature is 10 ℃, controlling the power of the electromagnetic induction heating pipe 15 to be reduced by 2kw.
After the startup control is used for the system startup work stability, whether the yield of the associated gas is enough for heating is judged, and if T is judged Oil outlet ≥T Oil device It means that the yield of associated gas is sufficient, and the electromagnetic induction heating pipe 15 may not be started, if T Oil outlet <T Oil device If the yield of the associated gas is insufficient, the electromagnetic induction heating pipe 15 needs to be started through circulation control to perform auxiliary heating.
The circulation control is firstly carried out according to the temperature difference T between the set temperature and the actual detection temperature of the water inlet 601 of the water diversion chamber Water facilities -T Water inlet To set the power; then, the temperature is detected at intervals, power is adjusted according to the detection result, and T is adjusted Oil outlet Is controlled at T Oil device ~T Oil device Within a range of +10 ℃.
The hot water and heat exchange system adopts the combined heating of the associated gas and the electromagnetic induction, and when the yield of the associated gas at the wellhead is insufficient, the combined heating is supplemented by the electromagnetic induction, so that the associated gas of an oil well with insufficient yield of the associated gas can be fully utilized, and the economic and social efficiency is important.
In the description of the present invention, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.
In the description of the specification, reference to the description of "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.