Is it necessary to install both a vent valve and a water seal in an acidic water storage tank?
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A water seal has already been installed; now we are considering whether to add a vent valve. If a vent valve is needed, would nitrogen need to be connected as well? What should be done if the gas inside the tank breaks through the water seal? O(∩_∩)O Thank you @ylb913
This post was last edited by ylb913 on 2015-7-16 at 10:44. Initially, we only used water seals for breathing in contact with the atmosphere; the first sewage stripping system was put into use in 1990. It was not until pressure indicators were added to the tops of the sewage tanks in 1998 that true water seals became available for use (the first true positive and negative pressure water seals were used in 1994). A system for purifying the exhaust gas from the sewage tanks was installed at the end of 1999, and since then, the purified gas (without passing through the water seals) has been sent to the acid gas flare. At the end of 2007, another exhaled air deodorization tower was added. I’ve never used an exhalation valve. Nitrogen was started to be supplied to the sewage tank in May 2014 (under negative pressure), and shortly after that an explosion occurred in the sewage tank of YZSH.
Is nitrogen still being added to the sewage tank (under negative pressure)?
Yes, in the past air was drawn in under negative pressure; before nitrogen was introduced, there were explosions in the acidic gas flare lines, and during the major maintenance in 2013, a large amount of sulfur was found in the sewage tanks.
Is there a diagram for this small section? We have other buffer tanks that are sealed with nitrogen, with control valves on both sides; however, the pressure in those tanks is quite high. It doesn’t seem feasible to install control valves on both sides of this tank at normal pressure. .
This post was last edited by ylb913 on 2015-8-20 at 14:04. First of all, a pressure gauge with kilopascal readings is required; the selection of control valves isn’t clear. We added it temporarily, and at present it is still manually adjusted using hand valves. The design pressure of our tank is -490~1970 Pa.
The design pressure for ordinary raw water tanks is usually several thousand pascals; it definitely is in pascals. In your case, it would be better to have the design institute do the calculations first before selecting a control valve
It seems like it’s not easy to choose such a control valve. .
The buffer tank can be controlled with just a few dozen PAs
Ours is 1.5 kPa. Have you added a water seal and a vent valve?