What if the gas-liquid ratio of the gas station is unqualified? Reasons for the high and low levels and adjustment methods

What should I do if the gas-liquid ratio at the gas station is not up to standard? Direct answer: If the gas-liquid ratio is too high, it is mostly due to the proportional valve opening being too large or the vacuum pump suction being too strong. When refueling, more gas is returned to the tank than the oil replacement amount, and the tank pressure is continuously pushed up; Low values are commonly seen in situations where the liquid resistance of the recovery pipeline increases, the pump head wears out and the suction force decreases, or the gas collection hood is damaged and leaks air. Adjust the order from easy to difficult: first adjust the proportional valve back to the interval, if it cannot be solved, then investigate in the order of pump head, pipeline, and seal. Gas liquid ratio is the core indicator of secondary recovery health. Long term deviation from the range not only affects the detection conclusion, but also causes frequent start stop of three devices due to tank pressure fluctuations, affecting two indicators at one location. This article explains the reasons and adjustment methods for the high and low values separately, and the site can check and verify them according to self inspection.

What does the gas-liquid ratio reflect

The gas-liquid ratio refers to the ratio of the volume of gas recovered during refueling to the volume of oil produced at the same time, reflecting the degree of synchronization between secondary recovery and refueling actions. A high ratio indicates that the system is pumping too much, bringing back air that should not have been pumped, raising the tank pressure, and increasing the burden on the tertiary device; A low ratio indicates that the amount of oil and gas that should be collected is sufficient, and there is an increase in leakage at the refueling site, which is accompanied by the risk of odor and detection. The detection of gas-liquid ratio is based on intervals rather than numerical points. Only when each gun falls within the interval and is stable, can the system be considered healthy; Single shot out of bounds, checking that gun is more effective than reworking the entire station.

Reasons and adjustments for the overestimation

Look at two places first if they are too high. One is the opening degree of the proportional valve: Some fuel guns come with regulating valves, or proportional valves are installed at both ends of the hose. If the opening is too large, the return air volume will be large. According to the manufacturer's instructions, use an internal hexagonal screw to adjust it slightly clockwise and counterclockwise. After each small adjustment, retest and do not overtighten it all at once. The second is the suction force of the pump: new or newly maintained pumps have high efficiency and strong return air, which can be appropriately lowered through variable frequency parameters or operating logic. Adjust each gun and keep records. Each gun has different degrees of wear and tear, and calibrate one by one, which is much more precise than a one size fits all approach for the entire station.

Reasons and investigation for the low level

Low probability screening. Pipeline liquid resistance: Insufficient slope or partial sinking of the secondary recovery pipeline, accumulation of condensate and rust impurities causing gas resistance, and easier condensation of oil, gas, and water vapor in winter, which can worsen symptoms; The common practice is to blow the pipeline with nitrogen gas and promptly drain the accumulated liquid in the collection tank. Wear of pump head: Pistons, blades, and sealing rings are vulnerable parts, and the suction force decreases after wear. They should be checked and replaced according to the maintenance cycle. Leakage of gas collection hood and joint: During refueling, oil and gas escape from the damaged area, and most of it can be detected by visual inspection and tactile sensation. The cost of conducting three inspections is not high, and most of the low issues can be resolved in the first two steps.

Reason and Disposal Control

Adjustment and retesting steps

1. Retrieve the inspection report to confirm whether it is high or low, as well as the gun by gun data;
2. Adjust the proportional valve first if it is too high, and record the small adjustments for each gun;
3. First, blow the pipeline and drain the collection tank, and then check the pump head if it is too low;
4. Check the gas collection hood and joints, replace damaged parts;
5. After adjustment, use the detection port to retest the gas-liquid ratio of the entire gun;
6. Write parameters into the device ledger for future reference.

Frequently Asked Questions

What is the normal gas-liquid ratio?

The detection of gas-liquid ratio is based on intervals, and the equipment and gun types at each station are different. The current detection caliber and equipment debugging records shall prevail; The setting value ledger during acceptance and debugging is the benchmark for this site.

Do you want to adjust it yourself or find a manufacturer?

Proportional valve fine-tuning and liquid collection tank drainage can be done by oneself, with simple tools and low risks; It is recommended that the replacement of the pump head and the setting of the vacuum degree be carried out by professional personnel, and after adjustment, retesting and retention should be carried out.

Do the three devices need to be adjusted after the gas-liquid ratio is adjusted?

It is recommended to observe the tank pressure and the frequency of starting and stopping the three devices for a few days. After the gas-liquid ratio returns to the interval, the tank pressure becomes more stable, and the starting pressure generally does not need to be changed; Repeatedly check the set value according to the tank pressure curve when starting and stopping frequently.

This article is organized by Luoyang wohong petrochemical equipment co., ltd. the company provides design, manufacture, installation, commissioning and operation and maintenance services for oil and gas recovery equipment, solvent recovery devices and buried composite pipe networks at gas stations, oil depots and chemical enterprises. if you need scheme configuration or on-site investigation, please contact and exchange.