Know Nitrogen

　　Nitrogen is a colorless, odorless and odorless gas under normal conditions, and is usually non-toxic. However, when the nitrogen content in the environment gradually increases and the oxygen content gradually decreases, people will be dizzy, and severely cause suffocation or even death. Let's take a look at the harm and protection of nitrogen to avoid the harm of nitrogen. The proportion of nitrogen in the atmosphere is 78%, because nitrogen is inactive and cannot support combustion or directly react with other substances at room temperature. When the nitrogen content in the environment gradually increases and the oxygen content gradually decreases to 19%, people tend to feel dizzy. As the proportion of oxygen continues to drop, it will cause simple asphyxia. The main manifestations are hypoxia, dizziness, headache, difficulty breathing, shortness of breath, rapid heartbeat, weak and fast pulse, trance, general fatigue, and muscle coordination and movement disorders. If you enter a device or container that is completely filled with nitrogen, you will immediately faint and suffocate until death.

　　In normal chemical production, nitrogen is often used to empty the combustible gas in the pipeline. Because nitrogen is colorless and odorless, the low oxygen environment created by nitrogen purging is often ignored by workers and even grassroots managers. Let us understand the hazards of nitrogen through the following case where two workers died in a confined space at the Varelo refinery in Delaware, USA.

　　CSB conducted a detailed analysis of the accident and issued a safety announcement. The accident occurred on a facility that processes 180,000 vehicles of crude oil a day, and the contractor's personnel installed a pipeline. The tank under the staff's position has just been purged with nitrogen. The metal pillar at the entrance of the tank top is also wrapped with a warning tape that prohibits entry, and a warning sign indicating "Danger" is forbidden to enter without permission. But there is no explanation of the danger of nitrogen. The maintenance staff did not make a safety report on the presence of nitrogen. The operator found a roll of tape 5 feet from the bottom of the tank when cleaning the tank mouth. The tape must be taken out before the pipeline was installed. They could choose to have a professional confined space work team come to clean the tape, but this process took several hours, and there was not much time left for them to change the elbow. In order to avoid delays, an operator was working Very close to the opening, I tried to hook up the tape with a wire, but it was unsuccessful. An operator was sitting on the edge of the boot, with two legs stretched into the tank, but he still could not remove the tape. At this time, there are two possible accidents. Under the supervision of the nearby personnel, the operator tried to quickly enter the tank, pick up the tape, and then go out. Or because of inhalation of the high concentration of nitrogen in the tank, suddenly dizzy and unconscious and fell into the tank. Upon seeing the situation, the guardian outside immediately set up a ladder and entered the tank to help the worker who fainted. However, this was an even worse tragedy, and he also fell due to the lack of an air respirator. Other people on the scene immediately pressed the emergency alarm button and used the walkie-talkie to report the situation. When rescuers arrived, they found that the hand-held tester in the hands of the fainted worker showed that the oxygen content was less than 1%. Professional rescuers put on air respirators and set up the hinges to enter the tank for rescue. However, 10 minutes had passed by this time, and finally two workers died because the rescue failed. The accident happened because the employee believed that he could quickly enter the tank and take out the tape and leave quickly. American security experts pointed out that this is a wrong idea. It is very unreliable to hold your breath and get in and out quickly, because the time to hold your breath is not enough to complete this thing. Inhalation of high-concentration nitrogen at the entrance of a confined space can also cause insufficient oxygen and fainting. It should be particularly pointed out that after a colleague is in danger, other people will be very anxious to rescue them, and even enter directly and die without wearing any PPE equipment. This is not a question of staff's judgment on the accident, but a question of training. If the staff are properly trained and exercised, this will not happen. This case shows that in a location close to the opening of the confined space, when hypoxic air is inhaled into the lungs, it affects people's judgment and coordination, and people will eventually fall, coma, or die without an exit.

　　Dur Gas Equipment reminds you that from the accident, rashly entering the confined space and other workers entering the tank without protective measures all reflect the lack of understanding of the harmfulness of nitrogen. Otherwise, this tragic accident can be completely avoided. Preventive measures: To identify the risk of nitrogen, where there is a high concentration of nitrogen, clear signs and warnings must be carried out. For all employees and temporary workers, education and exercises on access to confined spaces should be strengthened, and they can only take up their posts after passing the assessment.

　　Nitrogen is a colorless, odorless, non-toxic gas under normal conditions. Nitrogen accounts for 78% of the air content. The gas density under standard conditions is 1.25g/L, and the solubility of nitrogen in water is very small. Nitrogen will liquefy into a colorless liquid at a very low temperature of -196℃, and when the temperature is further reduced to -210℃, it will form a white crystalline solid. In the gas industry, black seamless carbon steel cylinders are usually used to hold nitrogen. According to the purity, it is divided into pure nitrogen, high-purity nitrogen and ultra-pure nitrogen. When used in large quantities, you can choose liquid nitrogen dewars, liquid nitrogen storage tanks and other nitrogen Supply method.

　　Dur Gas Equipment

　　1. Large atmospheric low temperature storage tank

　　500--50 thousand cubic meters of LNG, liquid oxygen, liquid nitrogen storage tanks, etc.;

　　2. Low temperature vacuum storage tank

　　10 Li-250 Li, LNG storage tank, oxygen, nitrogen, argon, storage tank;

　　3. Air-heated vaporizer

　　100 party-10,000 party

　　4. Water bath vaporizer

　　500～100,000 cubic meters

　　5. Pressure regulating skid, gasification station, urban peak shaving station

　　6. ​​PSA pressure swing adsorption nitrogen production, VPSA pressure swing adsorption oxygen production

　　Wealth Hotline Dürr Equipment

　　Zhu Dongfeng 18937809909