Synthetic Ammonia Process Technology Exchange Area [Daily Question 2009-03-19]

It seems this question is designed for those who have experienced driving in the old-fashioned way, but these people are probably quite old and don’t use the Internet much; they have actually never seen driving in that traditional style. I look forward to hearing the insights from those who have truly experienced driving in primitive conditions. This post was last edited by chen3jun on 2009-3-17 17:25]

The term \"high-pressure machine\" seems to be used less these days. When cleaning compressors, it is necessary to start from one section; the inlet at the beginning of that section of the compressor can be removed, as well as the outlet of the buffer tank. Then, a crane is used to lift this section of pipe to the side, and the pipe is cleaned using gas coming from the desulfurization process. For cleaning the area right after the compressor’s inlet, the compressor itself can be used to generate air pressure. It can also be carried out together with the compressor load test.

1. Before cleaning, remove all the pressure gauges, safety valves, oil drainage valves, and discharge valves of the main separator in each section; also remove the inlet pipe sections of Section 1, the cold oil discharge area, the location before the oil separator, the valves, and the balance section. Install a blind plate at the inlet pipe section of Section 1 – the purpose of this is to prepare for cleaning the main pipe of Section 1. Disconnect at the inlet of each compressor; be sure to open the access before the main gas inlet valve. A filter screen must be installed at the inlet to prevent debris from entering the compressor. Install inlet and outlet valves at this section, remove the front flange of the outlet buffer and pry it open by a certain distance; use a blind plate to block the inlet of the outlet buffer. Start the compressor following the normal procedures; dirt and gas will be blown out through the opening, causing the gas to flow in an impulsive manner. Apply white paint to an iron plate or wooden board facing the direction of gas flow, leave it there for about a minute to check for any debris, and it is considered qualified once no contaminants are present. After passing the inspection, install an outlet buffer flange; then, using the same method, remove one inlet flange of the cold exhaust coil, and clean it using the same procedure. After that, reinstall the flange. Next, remove the inlet flange of the oil-water separator, and clean it in the same way; once cleaned, reinstall the flange. Then, remove the oil discharge flange, the safety valve flange, and one inlet flange of the buffer – clean them all using the same method. After cleaning, reinstall the flanges. Remove the inlet flange of the compressor’s second stage, and clean it using the same procedure. Finally, after cleaning, reinstall the flanges and the inlet and outlet valves for the second stage, as well as the front flange of the outlet buffer of the second stage, and clean it using the same method. Paragraphs 2, 3, 4, 5, 6, and 7 are handled in the same manner. 2. Pressure control: For the low-pressure stages, stages 1 and 2 have a pressure of 0.15 MPa; stages 3, 4, 5, 6, 7, and 8 have a pressure of 0.2–0.3 MPa. The pressure must be controlled appropriately during cleaning, and the gas should flow in pulses. 3. When blowing out the residue, use a wooden mallet to strike the pipeline to clear it. 4. After the purging is complete, check that everything is normal before proceeding with pressure testing and airtightness checks.

Generally, one splits the pipeline open and blows air in to clean it out. But once, to save time, I removed the blind flange at the end of the 1-out/1-in pipeline and used air to clean it. While cleaning, I would hit the pipe with a wooden rod. At the outlet, I used white paper to check for any dirt. For the welded joints, I used soapy water to test for leaks.

It should start with a section; the inlet at the beginning of that section on the compressor can be removed, as well as the outlet of the buffer tank. Then, a crane can be used to lift this section of pipe to one side, and the pipe can be purged using gas coming from the desulfurization process. Purging after the gas enters the compressor can be done by using air generated by the compressor itself. It can also be carried out together with the compressor load test.

What a coincidence! ! I recently participated in the purging of a newly installed high-pressure machine these past few days. The first thing that comes to mind is that it’s too noisy! The sound of hitting the pipes and the noise from venting are unbearable to the ears! Air is used as the medium. First, remove the short circuits at the cylinder inlets in each section as well as the oil-water valves in the separators; install baffles at the cylinder inlets and the equipment inlet. Then, in sequence from section 1 to section 7, tap the pipes with a hammer while starting the machine to pump air out for purging (with low pressure ≤ 0.2 MPa and high pressure ≤ 2.0 MPa). The process is considered successful when there are no impurities or visible particulate dust in the exhaust gas. Before purging, check first whether the oil and water circuits are intact and unobstructed ； The purge pressure is controlled through the vent valves in each section. Last edited by Yao Ling Shan on 2009-3-19 11:21.]