Liquid Oxygen Atmospheric Pressure Storage Tank

With the development of science and technology, the technology of storing materials in low-temperature tanks at atmospheric pressure has become increasingly mature. There are more and more low-temperature tanks being built in the country, and reports of large liquefied natural gas (LNG) tanks and liquefied petroleum gas (LPG) tanks being completed are constantly emerging.

Currently, large low-temperature tanks in the country are mainly divided into several types according to the storage medium: liquid oxygen tanks (-183℃); liquid nitrogen tanks (-196℃); liquid argon tanks (-186℃); liquefied natural gas tanks (-162℃); liquefied ethane tanks (-89℃); ethylene tanks (-104℃). Compared with other storage methods, atmospheric pressure low-temperature tanks have many advantages: compared to vacuum tanks and spherical tanks, low-temperature tanks have lower storage pressure, thus providing better safety; low-temperature tanks have achieved large-scale construction, occupying less land and reducing storage costs. The structure of low-temperature tanks is simple, construction is easy, and construction costs are reduced.

　　Product Details

Configuration Parameters

Volume: 200~50000m³

Working Pressure: 10Kpa~50Kpa

Insulation Method: Double-layer wall powder accumulation insulation.

Basic Types: Above-ground type, high platform type.

　Storage Medium

● Liquid nitrogen, liquid oxygen, liquid argon, liquefied ethane, ethylene, etc.;

　Configuration Parameters

Note: Tanks of any specifications between 200-50000m³ can be designed, manufactured, and installed according to user requirements.

　Process Flow System

Liquid Inlet System; Temperature System;

Liquid Discharge System; Gas Emission System;

Pump Recirculation System; Analysis Sampling System;

Interlayer Nitrogen Supply System; Safety System;

Liquid Level and Pressure Measurement System; Boosting System.

　　Tank Structure and Principle

Currently, the low-temperature tanks built by our company are all flat-bottomed arch-roof, vertical double-layer wall structures, with the interlayer using pearl sand powder accumulation insulation. The equipment consists of an inner tank, outer tank, bottom insulation layer, interlayer insulation layer, equipment ladder platform, valves, instruments, and foundation platform.

The inner tank mainly consists of the tank top, cylinder body, and bottom plate. All component materials are made of austenitic stainless steel, which can fasten the entire inner tank to the bottom foundation through anchor belts, and also prevent the inner tank from deforming outward at the bottom under lifting force.

The outer tank mainly consists of the top cover, cylinder body, and bottom plate. All component materials are made of carbon steel plates, and the outer tank bottom plate is laid on the foundation platform and fastened to the foundation platform through embedded steel plates.

A layer of foam glass bricks and concrete load distribution plates is laid between the bottoms of the outer tank and inner tank as the bottom insulation layer, allowing the liquid weight in the inner tank to be evenly distributed and transmitted to the foundation platform.

The interlayer of the storage tank is filled with pearl sand powder as insulation, and dry nitrogen is filled in the interlayer to keep the insulation material dry, maintaining good insulation performance and a low daily evaporation rate for the storage tank. An operation platform is set up outside the storage tank, and the valves and instrument panels are concentrated on the operation platform for convenient operation.

　In operation, to ensure the safety of the storage tank, the inner tank is equipped with safety devices, one for overpressure protection and another for negative pressure protection, with two protective devices set for each of these aspects:

The first protection is: for overpressure protection, there is an automatic control vent valve at the top of the inner tank that discharges pressure automatically when the pressure exceeds the set value; for negative pressure protection, to prevent negative pressure in the tank when a large amount of low-temperature liquid is output, the storage tank is equipped with a self-pressurization system that can automatically replenish gas according to the pressure in the tank, maintaining positive pressure in the tank.

The second protection is: a breathing valve is installed at the top of the inner tank, which opens to relieve pressure when the pressure exceeds the positive pressure upper limit, and when the negative pressure in the tank exceeds the set value, the safety valve opens to draw in atmospheric pressure to protect the storage tank. The top of the outer tank has a breathing valve and an emergency vent valve. The breathing valve is used to maintain a slight positive pressure in the interlayer and has both inhalation and exhalation functions. The emergency vent valve is used in emergencies, that is, when liquid from the inner tank leaks into the interlayer and vaporizes rapidly, causing the pressure in the interlayer to rise quickly, the emergency vent valve opens to relieve pressure and prevent accidents. In addition to the above safety devices, the storage tank is also equipped with a liquid level gauge, pressure gauge, analysis sampling valve, and other instruments.

Industries applying large low-temperature liquid storage tanks: aerospace, machinery industry, electronics industry, geological mineral departments, metallurgy industry, construction and environmental protection, transportation departments, petroleum, chemical industry, electric power, energy, agriculture, forestry.