| 主权项 |
1. A method of liquid air energy storage and recovery comprising:
charging a liquid air energy storage (LAES) with power from a power source, the charging including storing thermal energy, discharging the LAES including generating electrical power by converting liquid air resulting from the charging and thermal energy resulting from the storing thermal energy, the discharging resulting in the withdrawal of thermal energy from a cold storage by discharged air, the discharged air, the charging including:
sequentially compressing charging air in a plurality of intercooled air compressors up to a charging pressure exceeding the air critical point;storing, for recovery during the energy storage discharging, the compression heat extracted from pressurized charging air resulting from its intercooling and aftercooling in a compression heat storage;deep cooling a charging air stream and its liquefaction, resulting from exchange of thermal energy with cold storage medium and a vent air stream;expanding the liquefied charging air stream with succeeding separating the resulting liquid and gaseous phases of expanded stream;cooling the charging air, using a vent stream, and storing a resulting liquid phase of the charging air at near atmospheric pressure in liquid air tank; discharging the LAES, including:
pumping a discharged liquid air stream up to pressure exceeding a pressure of charging air at a final charging compressor outlet during charging;preheating and vaporizing a liquid discharge air stream at least partially using thermal energy from the cold storage medium;further preheating and superheating a discharged air stream using the stored compression heat from the compression heat storage; andexpanding a resulting superheated discharge air stream, in a plurality of air expanders including reheating the expanded air stream using a stored compression heat; wherein the charging includes compressing the inlet air in the plurality of the air compressors up to charging pressure exceeding its critical point at the last compressor outlet by 2-4 bar at most, wherein the discharging includes pumping the liquid air up to discharging pressure exceeding a charging air pressure, wherein the charging includes deep cooling the charging air stream down to a temperature at the deep cooling system outlet, selected in the range from -170° C. to -180° C. and allowing the resulting charging air stream to reach a target air liquefaction ratio in the range from 75 to 85% at a practically atmospheric pressure in the liquid air tank, wherein the charging includes conducting a process of deep cooling the charging air stream in first, second and third sequential stages, wherein the air temperature is progressively reduced from a temperature at the deep cooling system inlet down to a selected outlet temperature and wherein a temperature drop at the second stage reduces charging air temperature by 1.5-38.5° C., beginning from a temperature at which air heat capacity achieves its maximum value in a process of air deep cooling, wherein the charging includes dividing the charging air stream at the inlet of the first stage into two parallel streams and passing the first stream through the first cold exchanger in the direction opposite to a vent vapor stream and passing the second stream through a first portion of the cold storage, resulting in a same outlet temperature of both streams which are combined including simultaneously providing a mass-flow relationship between the first and second streams of (9%-17%) : (91%-83%), wherein the charging includes dividing the charging air stream at the inlet of the second stage into three parallel streams, providing in-parallel passing the first stream through the second cold exchanger in the direction opposite to a vent vapor stream, the second stream through the second cold storage and the third stream through a balance cold exchanger being serviced by an external cold source, resulting in the same outlet temperature of all streams combined at the outlet of the second stage, and simultaneously providing the optimal mass-flow relationship between the first, second and third streams of (3%-8%) : (20%-51%):(46%-76%), and wherein the charging includes dividing the charging air stream at the inlet of the third stage into two parallel streams, in-parallel passing the first stream through the third cold exchanger in the direction opposite to a vent vapor stream, and the second stream through the third cold storage, resulting in the same outlet temperature of both streams combined at the outlet of the third stage, and simultaneously providing mass-flow relationship between the first and second streams of (9%-57%):(91%-43%). |
