Nitrogen has a number of effective usage in the oil and gas, onshore and offshore pipeline industries due to its unique properties. In hazardous situations and environments, dry and inert nitrogen creates a safe working environment for carrying out a number of maintenance works ahead of shutdown and start-up operations.
We, ISISAN Engineering
Nitrogen Purging will reduce your downtime by using the best and cost-effective purging solutions. Our experts and the high quality equipment, make sure that you are provided with the best suitable procedure, leaving your system purged and ready for operation in minimal time.
ATMOSPHERIC PRESSURE PURGING:-
We pass nitrogen gas continuously into the system at one point, while the air or gas being purged, exits from another point. The system is normally purged to atmosphere, so it remains at atmospheric pressure. Nitrogen performs its function by displacing or diluting the contents. Usually, both of these processes occur simultaneously. Hydrocarbons can be purged to atmosphere using mobile gas flairs.
PRESSURE CYCLE PURGING:-
We pressurize the system with nitrogen, which allows for mixture. This method is restricted to systems which can withstand the necessary pressure and is particularly suitable for complex system configurations and when simple atmospheric pressure purging procedures are not suitable.
Purging may be achieved by pressurizing with one or several pressurization cycles. The number of cycles or the pressure point of the system is dependent on the required ‘end point’ gas concentration.
VACUUM CYCLE PURGING:-
This method is similar to pressure cycle purging except the system is evacuated before nitrogen is introduced in order to break the vacuum and mix with the residual gas. The ideal situation to apply this method would be the complete evacuation of a system before the introduction of a single system volume, which would return the system to atmospheric pressure and reduce the gas concentration to zero. To reach the required ‘end point’ gas concentration, multiple cycles can be executed.
Air, nitrogen and vacuum drying techniques will thoroughly remove moisture and water from your system prior to start-up. We achieve your optimal dew point level so that you can be sure of the integrity of your product and the ongoing performance of your system.
Prior to commissioning and start-up, it may be essential to carry out a drying procedure to thoroughly remove water and moisture from the system. This procedure will help to maintain the purity of the product to be transported through the system, minimize corrosion (growth) and optimize efficiency and safety.
We provide flexible solutions for completely drying your system ahead of start-up. This is necessary following a pressure or leak/tightness test during pre-commissioning in order to achieve the required dew point levels. Our personnel have the knowledge and expertise to assess your particular situation and advise the safest, most reliable and most cost-effective solution.
Liquid nitrogen can be delivered in high volume and vaporized into gaseous nitrogen through our high flow pumps which offer ten times the flow rate of a normal compressor. This dryer and inert gas can be used to push moisture outside the system to produce a dew point of approximately -60°C while inserting the system at the same time.
The purpose of pneumatic testing is to verify that a system may be safely subjected to its maximum operating pressure by testing it beyond its designed pressure limit. In the pneumatic pressure test we use nitrogen as test medium, to pressurize the system to 110% of its designed pressure limit. A holding period is then applied for a fixed amount of time and the results monitored to determine the safety and integrity of the system.
BENEFITS OF PNEUMATIC TESTING
In circumstances when hydrostatic testing is not possible, for instance, the weight of hydro test water is too high for the pipe support system (e.g. gas service piping) and when the introduction of water to the piping may be detrimental to the process (e.g. catalyst or reactor contamination, cryogenic service system), then the components or system can be tested with nitrogen.