High-pressure, pure oxygen combustion

　　Typically, the oxygen content in air is ≤21%, and the combustion of fuels in industrial boilers and furnaces also takes place under such oxygen levels. Practice has shown that when the oxygen content in the gases burned in boilers reaches over 25%, energy savings of up to 20% can be achieved； The boiler’s startup heating time is reduced by 1/2 to 2/3. 　　Oxygen enrichment involves using physical methods to extract oxygen from air, resulting in a gas composition with an oxygen content of 25%–30%. Feeding this portion of oxygen-enriched gas into the boiler or furnace as secondary air can increase the overall or local oxygen level inside the furnace, reduce the overall air excess coefficient there, and effectively lower the exhaust temperature by preventing the excess air from carrying away heat when the air excess coefficient is high. An increase in oxygen content can improve the conditions for ignition, ensuring complete combustion; this helps save fuel while also contributing to environmental protection. Oxygen-enriched combustion has the following advantages: 1. It increases the thermal energy utilization rate and raises the flame temperature, thereby achieving the goal of saving energy and reducing consumption. For example: Glass furnaces can save 5–15% in energy consumption and increase production by 5–10% ； Industrial boilers can save 5–15% in energy consumption. 　　2. Reduce the air excess factor, decrease the amount of exhaust gas, lower the smoke blackness value, and reduce environmental pollution. 　　3. The equipment has good overall performance, is easy to install, delivers excellent results, and allows for a rapid return on investment. 　　4. Short installation period with quick results. 　　Oxygen-enriched combustion can be applied to industrial coal-fired boilers, gas boilers, oil-fired boilers, waste incinerators, glass furnaces, cement kilns, ceramic furnaces, and metal smelting furnaces, among others. 　　Our company can provide users with technical advice on oxygen-enriched combustion, as well as oxygen-enriched burners and related equipment.

Under specified conditions, the minimum oxygen content required for a solid material to maintain stable combustion in a mixture of oxygen and nitrogen gases is known as the oxygen index. The oxygen index of a material indicates the ease with which it burns. A high oxygen index indicates that the material is difficult to burn, while a low oxygen index indicates that the material is easy to burn. It is generally believed that materials with an oxygen index of <22 are flammable, those with an oxygen index between 22 and 27 are combustible, and those with an oxygen index >27 are difficult to ignite. 4. Which substances, when in contact with pure oxygen, can cause it to oxidize, self-ignite, or explode? When pure oxygen comes into contact with mineral oils, greases, or finely dispersed combustible dusts, carbon powder, or organic fibers, it can cause spontaneous ignition or explosion due to intense oxidation and heat accumulation. Therefore, pure oxygen must never come into contact with oils and organic substances, and operators must under no circumstances use pure oxygen to purge work clothes.

Oxygen is one of the most widely distributed elements in nature, and it is a substance essential for the survival of living organisms. It exists in the air in a free state; by volume, oxygen makes up 20.93% of the air. Oxygen exists in combined form in water, minerals, as well as in all animals and plants. Oxygen is a colorless, transparent, tasteless, and odorless gas at room temperature and pressure, and it is slightly heavier than air. At atmospheric pressure, when cooled to -182.96°C, oxygen condenses into a sky-blue, transparent, and fluid liquid ； When the temperature drops to -218.4°C, it condenses into blue solid crystals. Oxygen has highly reactive chemical properties; it is a strong oxidizing agent and a fuel accelerator. With the exception of gold, silver, and the inert gases helium, neon, argon, krypton, and xenon, which generally do not react with it under normal conditions, oxygen can combine with other substances to form oxides. The intensity of the oxidation reaction depends on the concentration and pressure of oxygen; if the oxidation reaction takes place in pure oxygen, it is very intense and a large amount of heat is released. (For example, when metals react with oxygen, increasing the purity and pressure of oxygen significantly accelerates the oxidation reaction; the ignition point of metals decreases as the oxygen pressure rises.) When oxygen is mixed in a certain proportion with flammable gases such as acetylene, hydrogen, and methane, an explosion occurs upon exposure to fire. After being compressed, oxygen generates a large amount of frictional heat during transportation when there is grease, iron oxide particles, or small combustion residues (such as coal dust, carbon particles, or organic fibers) present; these substances cause friction and impact against the pipe walls or the machinery as they move with the airflow, leading to fires in the pipes and machinery. Or, due to the sudden opening of a valve in the pipeline, the gas behind the valve reaches a temperature akin to that of adiabatic compression, causing the pipeline or valve to ignite. Clothing and other organic textiles saturated with oxygen will catch fire immediately upon contact with an ignition source. Porous organic materials impregnated with liquid oxygen can explode when ignited or subjected to a sufficient impact force. Liquid oxygen, after being subjected to weak discharge over a long period of time, turns into dark blue liquid ozone, which is prone to explosion. Oxygen is paramagnetic; oxygen molecules can acquire magnetism under the influence of a magnet and can be attracted to magnetic poles. Based on this property of oxygen, magnetooxidometric analyzers can be made to analyze the purity of oxygen. At atmospheric pressure, oxygen poisoning can occur when the oxygen concentration exceeds 40%. When inhaling 40%-60% oxygen, discomfort behind the sternum and mild coughing occur, followed by chest tightness, a burning sensation behind the sternum, and difficulty breathing, with the cough worsening ； Severe punishment can lead to pulmonary edema, and even respiratory distress syndrome. When the inhaled oxygen concentration exceeds 80%, facial muscle twitching, pale complexion, dizziness, tachycardia, and collapse occur, followed by severe convulsions throughout the body, coma, respiratory failure, and death. Prolonged exposure to an oxygen partial pressure of 60–100 KPa (corresponding to an oxygen inhalation concentration of about 40%) can cause eye damage, and in severe cases, blindness may occur. It is recommended that emergency responders wear self-contained positive-pressure breathing apparatus and standard work clothing. Avoid contact with combustible or flammable materials. Seal the source of leakage as much as possible. Ensure proper ventilation to enhance diffusion. Oxygen is widely used in industrial production; for example, liquid oxygen can be used as an oxidizer in the defense industry for rockets ； Moreover, cutting and welding in the machinery industry ； Oxygen steelmaking, rolling, and non-ferrous metal smelting in the metallurgical industry ； And large amounts of oxygen are also needed for medical purposes and deep-water operations. 2 Oxygen production process flow. The methods for producing oxygen can be broadly divided into chemical methods, electrolytic methods, adsorption methods, and cryogenic separation methods. Since air contains about 21% oxygen and is an inexhaustible resource, modern industry uses the cryogenic separation method to produce oxygen. The raw material for this process is air; air is drawn in by auxiliary towers, compressed and cooled several times. As the pressure of the air is reduced, it cools down to very low temperatures, causing it to turn into a liquid. The various liquid gases contained in liquid air have different boiling points; for example, the boiling point of liquid nitrogen is -195.802°C, while that of liquid oxygen is -182.962°C. These differences in boiling temperatures are utilized to cause liquid air to evaporate. Initially, nitrogen with a low boiling point evaporates; as nitrogen evaporates, the oxygen content in liquid air increases. This process is known as distillation. Through repeated distillation and purification, high-purity oxygen can be obtained. Oxygen production can be classified into four types based on the pressure of compressed air used in the production process: high-pressure process, medium-pressure process, dual-pressure process, and fully low-pressure process. Although the air separation equipment (i.e., oxygen generators) used in these different processes vary, the entire oxygen production process generally involves the following six main stages: ① Removal of dust and impurities from the air ； ②Air is compressed by a compressor ； ③Remove carbon dioxide and water vapor from compressed air ； ④Liquefy air ； ⑤Liquid air is separated into oxygen and nitrogen through distillation ； ⑥Storage and transportation of products. Taking an oxygen generator with a capacity of 50 cubic meters per hour as an example, its production process is shown in the figure below

Oxygen-enriched air can also be used in coal gas production processes; for example, in recent years China has developed a continuous oxygen-enriched gas production process for coal gasification.

There are several oxygen-enriched gasification manufacturers in Henan, such as the Pingdingshan Feixing Group