To lessen operational costs in today’s unstable economy, a lab or facility manager with a new ICP/Mass Spec system must cost-effectively use cryogenic liquid argon dewars to deliver gaseous argon.
In terms of specific critical gases requirements, one attractive option is using Lng vehicle cylinder, commonly called dewars, to deliver gaseous argon to ICP and ICP/Mass Specs. Argon’s unit cost per cubic foot/gaseous liter is significantly lower when sent to your facility in cryogenic liquid form in dewars. However, because these containers keep the gas inside a cryogenic form until it really is dispensed as being a gas, the two main concerns that can reduce the cost-effectiveness of using this mode of supply.
Because the argon is saved in self-pressurizing containers with relief valves and also the cryogenic liquid is boiling inside, reserve containers awaiting the main container to empty on the system will, after a while, build internal pressure before the relief valve setting is reached then start to vent excess gas at a rate of 2 to 3 percent per day. This is basically the NER or Normal Evaporation Rate, referenced in the industry as being the “use it or lose it” phenomenon. Around this rate, when the reserve cylinder of argon contains 4,500 cubic feet of gas, it equals losing 135 cubic feet every single day it sits in reserve. It wouldn’t take very long to nibble on up whatever savings resulted in the lower unit cost.
Since the majority of the gas is cryogenic form, the stress inside the container will not indicate if the unit is full, half full or empty. The small liquid level indicators in addition to the dewars are hard to read through and never very accurate. Since the majority gas distribution systems rely solely on pressure to change from primary to reserve cylinders, false low-pressure readings might cause lab personnel to get rid of containers with as much as 25 % of your contents still inside.
Solution: CONCOA’s Intelligent Gas Distribution System IntelliSwitch II continuously monitors your reserve container’s pressure, using programmed software logic to figure out if a container is actually empty or contains residual product. IntelliSwitch II 538 Series will be the latest in the line of computer-controlled gas distribution switchover systems using very accurate transducers to keep track of both primary and reserve inlet pressures. Proprietary software logic uses this info to drastically reduce evaporation loss by switching towards the reserve dewar to supply the gas towards the instrument prior to the relief valve opens, drawing down pressure in the container to your programmed point, and after that returning to the primary dewar. This “economizer function” can virtually eliminate losses inside the reserve LNG filling Station.
Additionally, when primary dewar pressure drops beneath the point where the program switches for the reserve, IntelliSwitch II is not going to immediately conclude that the container is empty. It waits a programmable period of time and while offering the system in the reserve, watches the pressure reading in the primary. In the event the pressure rises 46dexkpky the switchover part of that point period, your computer concludes residual liquid was left within the container and switches to it to offer the instrument. It can do this repeatedly up until the dewar fails to build pressure above the programmable switchover point, in which time that it switches to the reserve, and sounds an alarm to indicate the principal is currently truly empty. This “look-back feature” decreases the residual discarded when utilizing dewars to below 2 to 3 percent.
Through the elimination of evaporation loss and reducing the residual left in empty containers, CONCOA’s IntelliSwitch II optimizes the fee savings of utilizing Cryogenic Centrifugal Pump to supply gas to ICP or ICP/Mass Specs.