Air separation oxygen production area: [Weekly Topic] Week 14 of 2011——How to reduce energy consumption in air separation

1. Reduce startup time. 2. Lower the incidence of accidents. 3. Coordination between demand units and production units. 4. Proper management. 5. Skillfulness, effectiveness, and relevance in operations. Points 2 and 5 are the most important

This range is quite broad; different processes lead to various optimization methods. In addition to optimizing our operations and improving the reliability of the equipment, we must at least reduce unnecessary emissions, and ensure good extraction rates for oxygen, nitrogen, and argon. Our unit once modified the molecular sieve system by using steam heating and added a gas-liquid separation tank to recover deionized water. We hope everyone will participate actively

First of all, I think this issue is related to the equipment; the equipment must be of good quality, as that will ensure a long operating lifespan. When leading procurement, one must have this mindset: spend large amounts of money at first and then less, or spend less at first and then more. In other words, what belongs to that province must remain part of it; anything that shouldn’t be part of the province definitely cannot be. Stable operation of equipment is a prerequisite for reducing energy consumption. Secondly, regarding the installation of the project, it is necessary to hire a reputable installation company for the task; nothing more needs to be said on this topic. Third is the issue of operational management after the vehicle starts running; it is necessary to ensure operation at full capacity for extended periods, as operating at low capacity increases operational costs. However, this needs to be adjusted according to the amount of gas used; it’s not appropriate to run at full capacity when the gas demand is low. Modern air separation units are generally capable of operating under varying conditions, and we adjust their operation based on the amount of gas required. At present, they are operating at a partial load, somewhere between a fully liquid-state operation and a 6000 oxygen output condition. Once a working condition is stable, gradual fine-tuning should be carried out to achieve the highest extraction rate. Generally speaking, I personally believe that the more stable air separation is, the higher its efficiency will be.

The last edit to this post was made by gader on 2011-4-6 at 11:12. Let me talk about what I’ve encountered in my actual work: 1. When the weather gets cold, it’s possible to reduce the amount of circulating water used. 2. If there is too much high-pressure nitrogen and it’s necessary to vent some of it, then the high-pressure nitrogen can be converted into low-pressure nitrogen using a throttle valve; this way, there’s no need to operate the nitrogen compressor. 3. Oxygen 4. Excess oxygen products can also be liquefied using an expander and recovered into tanks. (y& v$ O/ _* f, a( I4 R" J! W 5. The high-pressure air coming out of the booster is not passed through a throttle valve; instead, a liquid expansion machine is used. This requires a higher initial investment, but it is still cost-effective in the long run. If there are multiple options available for the product, instead of venting it, another pipeline can be installed along with a flow meter, which can then be sold to Linde.

Our unit is a 1-to-2 drive turbine-based setup; we strive to maintain a stable steam pressure, ensuring it isn’t too low. Whenever possible, we avoid opening the return valve and the vent valve as long as the total load allows, in order to minimize heat losses in the high- and low-pressure plates and improve the oxygen extraction rate.

1. Optimize compressor operation to reduce energy consumption. 2. Adjust the temperature difference in the middle of the main heat exchanger, control the temperature difference at the hot side, and minimize heat losses. 3. Regulate the expander properly to ensure a balance of cooling capacity

Firstly, low energy consumption is ensured through design: 1. Efficient machines and molecular sieves; 2. Efficient heat exchangers; 3. Efficient packing and low pipeline pressure drops; 4. Efficient condensation evaporators. Secondly, in terms of on-site installation and commissioning: 1. Proper installation; 2. Excellent commissioning to ensure successful operation as soon as possible; 3. High-quality equipment to guarantee low operating energy consumption. Lastly, there is daily management and operation.

In summary, it comes down to the stability and reliability of the device

1. Reasonably control process parameters； 2. Operator proficiency ； 3. Install a gas storage tank at the air separation outlet.

Purpose of adding an air storage tank: 1. To maintain pressure stability and reduce the impact of changes in user demand on the air compressor； 2. The moisture present in the air can be removed from the air storage tank, thereby reducing accidents such as equipment shutdowns caused by water in the compressed air.