Issues related to the loading and unloading of automotive fuels
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May I ask what is the maximum working time per day for loading and unloading oil products at an oil refinery? Is it only 8 hours of loading during the day, or is shift work day and night also possible? How many cars can one parking space hold in a day? If it’s all 50-cubic-meter tank trucks, is it reasonable to estimate that it takes 1.5 hours to fill one truck on average? Liquefied gas is generally avoided being loaded during the hot periods in summer; does gasoline and diesel also need to be avoided from being loaded during such hot times? If there are any reference materials or textbooks I can consult, please let me know as well. Thank you!
If the amount of oil to be filled is not large, generally two batches per day are considered: one batch is handled during the day shift, while no filling is done during the night shift. If the amount of oil loaded is very large, that’s a different matter. As for avoiding high-temperature periods, it mainly depends on the actual scheduling. As for the loading time, it takes about 1.5 hours from when the vehicle enters the gate to when it leaves it. The actual operation time was less than 1 hour.
I have another question for you, and I need to explain it in detail. For example, I want to load diesel onto vehicles; the annual production volume is 840,000 tons, with a density of 0.84. Assuming that loading takes place over 330 days per year, that means 3,000 cubic meters need to be loaded each day. With each vehicle requiring 50 cubic meters, 60 vehicles would be needed. Considering a variation factor of 1.5, the total number of loading stations required is 11.3; I’ll assume 12 stations. Now the question is: what should be the total flow rate of the loading pumps? In my opinion, if loading is done for 8 hours per day with a imbalance factor of 1.5, the actual loading time is 5.3 hours. Dividing 3000 liters by this gives 566 liters per hour; therefore, 600 liters per hour should be set as the target. Some experienced people say that 400 liters per hour is sufficient, as it’s not possible to load all the crane positions at the same time. The reason why it’s 400 rather than 500 or 300 isn’t clear; it’s just said to be based on experience, with 200 liters per hour being enough for 6 crane positions. But my calculations show that this is not enough; in other words, the loading time would be more than 8 hours. I did the math by assuming a loading rate of 400 cubic meters per hour. To load 3000 cubic meters, the actual loading time would be at least 3000/400 = 7.5 hours. Multiplying this by the imbalance factor of 1.5 gives 11.25 hours. Is this reasonable? I’m not majoring in storage and transportation; there are still many things I’m figuring out. Please give me some advice. Thank you.
The number of diesel and gasoline vehicles is usually highest between 3 p.m. and 5 a.m., as they need to cross many roads that cannot be used during the day. Do you mean a pump with a capacity of 400 liters that has multiple outlets? However, it’s not easy to control. On our end, we have 270 cubic meters per 5 connections, and frequency control is used for the pump. The impact exerted by the loading nozzles is quite significant; especially when 4 of the 5 connections are stopped at the same time, this puts a lot of stress on the remaining connection.
Planning to use a 200-liter pump, choosing 2 or 3 to operate in parallel
Personally, I think 400 liters per minute is a bit too little. If 3000 liters need to be delivered daily, it would take over 7 hours to pump out 3000 liters using a pump that delivers 400 liters per minute; moreover, it’s not possible to pump at that full rate all the time. When loading the liquid into a vehicle, the flow rate is slower at the beginning and toward the end due to certain requirements, but it can reach over 100 liters per minute when pumping at full capacity. Therefore, it is recommended to install 3 or 4 pumps in parallel, with variable frequency control for the pumps.
Yes, I think running 3 units of 200 liters each in parallel can meet the requirements
Personally, I think three units with a capacity of 200 cubic meters each is not enough. Based on what you’ve described, the factory relies entirely on trucks for transporting products; if there are problems with the pumps used for transportation, it will directly affect the amount of oil that can be delivered as well as the production of other equipment. Therefore, when considering the normal volume of deliveries, it’s necessary to have an additional unit as a backup. This is safer.
Loading usually takes 8 hours during the day. Try not to load the vehicle at night; people lack a sense of responsibility. It depends on whether you have started the pump at that parking space. 50 cubic meters takes 1.5 hours, which is too slow. Neither gasoline, diesel, nor LPG needs to be avoided during high-temperature periods.