1.2.3 LNG Storage Vessel Gas Supply Process:

All valves on the tanks to be pressurized, excluding the root valve and the emergency shutdown valve, are in the closed position.

2. Open the lower inlet valve of the low-temperature storage tank and the valves for the pressurized liquid and vapor phases, and check that both valves of the pressurized vaporizer are in the open position.

3. Open the low-temperature cutoff valve before the gasifier, the normal temperature flanged ball valve after the gasifier, and all valves required to be opened in the pressure regulation system.

4.A. When the gas supply rate is less than 1000-2000 Nm3/h, one storage tank is sufficient for liquid discharge to meet the gas supply requirements.

5. Output Liquids:

5.1 When the tank pressure rises above 0.15MPa higher than the discharge pressure, slowly open the liquid outlet valve to initiate the gas supply operation.

5.2 Record the liquid storage tank number and the start of gas supply time.

5.3 Pay close attention to the liquid level, pressure changes, and flow and pressure variations at the outlet when supplying gas.

1.2.4 LNG Tank Self-Pressurization Operation Procedure

1. During manual operation, open the valves: the boost liquid phase valve, the boost gas phase bypass valve, and the liquefied natural gas (LNG) receiver inlet valve, allowing LNG to flow directly into the self-boosting gasifier. After vaporization, it enters the LNG storage tank. At this point, closely monitor the pressure; close the boost liquid phase valve when the pressure in the LNG storage tank reaches the desired level.

2. Cautionary Notes:

(1) During operation, the LNG low-temperature storage tank must ensure that the maximum liquid level is ≤90% and the minimum liquid level is ≥15%.

(2) When manually operating the self-pressurizing system, it is strictly prohibited to leave the scene unattended.

(3) When the self-pressurizing system is in operation, the pressure-reducing system should be in the off state.

3. Cautionary Notes:

(1) During operation, the LNG tank must maintain a liquid level of ≥15%.

(2) When operating manually, the site must be strictly attended at all times.

1.2.5 Risk Analysis and Countermeasures

1) When loading and unloading LNG tankers, operators should wear masks, static-proof work clothes, and anti-freeze gloves, etc.

2) During LNG tanker unloading, it is strictly prohibited to move the vehicle to prevent the disconnection of loading and unloading hoses, which could lead to a large amount of LNG leakage.

3) When LNG is present in the pipeline, both ends' valves cannot be closed simultaneously.

4) Absolutely no touching or stepping on low-temperature pipelines and equipment.

6) Under no circumstances shall water, oil, mechanical impurities, etc., enter the pipeline to avoid blockages.

7) Absolutely no hammering, fire roasting, or water spraying on the frozen areas.

8) To ensure the safety of the working environment, operators must wear proper protective gear. Static electricity must be neutralized before entering the station. Open flames are strictly prohibited within the site's operational area, as well as the use of non-explosion-proof tools and electronic devices.

9) Strictly adhere to the operation ticket system, executing procedures as outlined on the ticket. The on-site operation requires at least two personnel: one to operate and another to supervise, ensuring operational safety.

10) Conduct safety education before operation, implement on-site safety precautions effectively. In case of danger, know how to evacuate and control the situation.

Operation Procedures for Low-Temperature Natural Gas Storage Vessels

1.1 Introduction to Site Pressure Regulation Process

An attached partial process flow diagram of the pressure regulating area is provided, with the equipment to be operated numbered in the process flow diagram.

1.2 Pre-pressing Preparation

1.2.1 Tool Preparation

Explosion-proof wrench, two pairs of gloves, and two sets of protective gear.

1.2.2 Pre-Work Preparation

Wear personal protective equipment, including anti-static suits, static-free shoes, and safety helmets, etc.

(2) Ensure that equipment prone to static, such as cell phones and computers, are placed in a safe area. Check if the surrounding environment is safe and meets the working conditions.

(3) Before entering, touch the static discharge device with both hands to release static electricity.

(4) Verify that all pressure-regulating tools such as explosion-proof wrenches are fully packed.

(5) Inspect that the tank's pressure gauge, level gauge, thermometer, flammable gas detector, and safety valve are all operating normally.

(6) Inspect the pipeline valves, pressure gauges, and safety valves to ensure they are in normal working condition.

(7) Prepare all explosion-proof tools