Efficient gas hydrate production system using flue gas waste heat / solar absorption heat pump to compensate reservoir heat

Patent metadata

Field	Value
Publication number	US-11879310-B2
Application number	US-202017415986-A
Country	US
Kind code	B2
Filing date	Aug 27, 2020
Priority date	Jul 17, 2020
Publication date	Jan 23, 2024
Grant date	Jan 23, 2024

Abstract

An efficient gas hydrate production system using flue gas waste heat/solar absorption heat pump to compensate reservoir heat, includes a heat source absorption system, heat pump heating system and reservoir heat compensation system. The invention uses the low-grade heat energy of offshore platform to solve the problems of heat source and energy consumption in the process of natural gas hydrate exploitation. It provides a commercial feasible scheme for large-scale exploitation of natural gas hydrate. The condenser module, evaporator module and injection well module of the invention can be flexibly increased or decreased, and can adapt to a variety of actual hydrate reservoir distribution; the injection well module adopts ball-nozzle, which can disperse and evenly inject the hot injected water into the reservoir, which is convenient for the rapid and effective transfer of reservoir heat and improves the speed of reservoir heat compensation.

First claim

The invention claimed is:

1. An efficient gas hydrate production system using flue gas waste heat/solar absorption heat pump to compensate reservoir heat, wherein the efficient gas hydrate production system using flue gas waste heat/solar absorption heat pump to compensate reservoir heat comprises a heat source absorption system, a heat pump heating system and a reservoir heat compensation system;
wherein the heat source absorption system is mainly composed of a flue gas heat exchange part and a solar energy heat collecting part;
the flue gas heat exchange part comprises a flue gas heat exchanger and a first flow regulating valve, and a circulating water heated by a hot flue gas in the flue gas heat exchanger flows through the first flow regulating valve to the heat pump heating system; the first flow regulating valve is used to regulate a temperature of the circulating water of the flue gas heat exchange part entering the heat pump heating system;
the solar energy heat collecting part comprises a second flow control valve and a solar collector, the solar collector is used for heating a low-temperature circulating water, and the heated circulating water flows into the heat pump heating system through the second flow control valve; the second flow control valve is used to regulate the temperature of the circulating water entering the heat pump heating system in the solar energy heat collecting part;
the heat pump heating system is mainly composed of a generator module, a condenser module, an absorber module and an evaporator module;
the generator module comprises a condensing tube, a concentrated solution tube and a solution circulating pump, the condensing tube realizes communication between a generator and the condenser module, a sprayer of the generator is connected with the absorber module through the solution circulating pump, and the concentrated solution tube realizes communication between the generator and the absorber module, an inlet of a primary heat release pipe in the generator is connected with the heat source absorption system, and an outlet is connected with the evaporator module, the absorber module comprises an absorber, the concentrated solution tube, an evaporation tube, a dilute solution pipe, a solution circulating pump and a water pump; the evaporation tube realizes communication between the absorber and the evaporator module; the dilute solution pipe connects a lower part of the absorber and the solution circulating pump; the concentrated solution pipe connects a sprayer of the absorber; an inlet of a primary heating pipe in the absorber connects the water pump, and the outlet is connected with the condenser module;
the condenser module comprises a condenser, a condensing tube, a condensate pipe, a U-connector and a hot water storage tank; the condensing tube realizes the communication between the condenser and the generator module, and the condensate pipe connects the condenser and the U-connector; an inlet of a secondary heating pipe in the condenser is connected with the absorber module, and the outlet is connected with the hot water storage tank;
the evaporator module comprises an evaporator, the U-connector, a condensate water pump, the evaporation tube and a circulating water pump; a condensate spray device in an inner upper part of the evaporator is connected with the U-connector; an inlet of secondary heat discharge pipe in the evaporator is connected with the absorber module, and an outlet of the evaporator is connected with the circulating water pump; the condensate water pump is below the evaporator, and connects the outlet of the evaporator with the condensate spray device in the evaporator;
the reservoir heat compensation system is mainly composed of an injection well module and production well module;
the injection well module comprises a hot water storage tank, an injection pump, an injection well, a ball-nozzle, a temperature controller, a thermocouple and an auxiliary heater; one end of the injection pump is connected with the hot water storage tank, and the other end is connected with the injection well; the other end of the injection well is connected with the ball-nozzle, and the temperature of the hot water storage tank is controlled by the temperature controller according to a signal of the thermocouple on an inner wall of the hot water storage tank, which is realized by controlling a switch of the auxiliary heater on a periphery of the hot water storage tank;
the production well module comprises a production well, a seawater storage tank, a gas-liquid separator, a gas collecting cylinder, a suction pump, a horizontal well, a multi-cluster production hole, the water pump, a ball valve and a water outlet pipe; a lower part of the production well is connected with the horizontal well with the multi cluster production hole, and an upper part of the production well is connected with the gas-liquid separator; a top part of the gas-liquid separator is connected with the gas collecting cylinder and a lower part of the gas-liquid separator is connected with the water outlet pipe; a lower part of the seawater storage tank is connected with the suction pump, and a middle part of the seawater storage tank is connected with the water pump; the seawater level of a seawater storage tank is controlled by the suction pump at the lower part of the seawater storage tank controlled by the ball valve inside the seawater storage tank;
an operation of the system includes a circulating water flow, solution circulating flow and injection water flow;
the circulating water absorbs heat in the flue gas heat exchanger and the solar collector and converges, enters the primary heat release pipe in the generator to exchange heat with a dilute solution outside the primary heat release pipe, enters the secondary heat discharge pipe in the evaporator to exchange heat with the condensate outside the secondary heat discharge pipe, returns to the heat source absorption system through the circulating water pump, and then flows into a heat exchange tube and the solar collector respectively;
the dilute solution circulates in the absorber module, the generator module, the condenser module and the evaporator module; the dilute solution exchanges heat with the circulating water in the first stage heat release tube in the generator; the water in the solution turns into steam, the remaining solution turns into concentrated solution and enters the absorber; the steam enters the condenser and exchanges heat with an injected water in the secondary heat discharge pipe and turns into condensed water; the condensed water enters the U-connector to depressurize, and then enters the evaporator to exchange heat with the circulating water in the secondary heat discharge pipe; the evaporated steam enters the absorber to mix with the concentrated solution to form the dilute solution, and at the same time exchanges heat with an injected water of the primary heating pipe in the absorber;
an injected water in the seawater storage tank flows in the absorber, the condenser and the injection well; the injected water in the seawater storage tank enters the primary heating pipe in the absorber through the water pump to exchange heat with the concentrated solution outside the primary heating pipe, and then enters the secondary heating pipe in the condenser to exchange heat with the water vapor outside the secondary heating pipe, and then enters the hot water storage tank for heat preservation; the hot water in the hot water storage tank enters the injection well through the injection pump, is evenly distributed at the ball nozzle to compensate the heat required for hydrate decomposition; the injected water and natural gas and water from hydrate decomposition flows from the multi cluster production hole through the horizontal well to the production well, and then into the gas-liquid separator; the produced water is discharged from

Assignees

• Univ Dalian Tech

Inventors

• Song Yongchen
• Yang Mingjun
• Wang Xinru
• Zheng Jianan
• Zhao Jiafei
• Jiang Lanlan

Classifications

• E21B43/01 Primary

  specially adapted for obtaining from underwater installations · CPC title

• E21B43/24

  using heat, e.g. steam injection · CPC title

• E21B43/295

  Gasification of minerals, e.g. for producing mixtures of combustible gases (E21B43/243 takes precedence) · CPC title

• E21B43/30

  Specific pattern of wells, e.g. optimising the spacing of wells · CPC title

• E21B43/34

  Arrangements for separating materials produced by the well · CPC title