To lower operational costs in today’s unstable economy, a lab or facility manager with a brand 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 choice is using Air separation equipment, 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 delivered 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, there are two conditions that can lower the cost-effectiveness of employing this mode of supply.
Considering that the argon is saved in self-pressurizing containers with relief valves along with the cryogenic liquid is boiling inside, reserve containers waiting around for the main container to empty on the system will, after a while, build internal pressure until the relief valve setting is reached then commence to vent excess gas at a rate of 2 to 3 percent per day. This is the NER or Normal Evaporation Rate, referred to in the marketplace as being the “use it or lose it” phenomenon. At the rate, in the event 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 require much time to eat up whatever savings resulted through the lower unit cost.
Since most of the gas is in cryogenic form, the pressure within the container is not going to indicate if the unit is full, half full or empty. The little liquid level indicators along with the dewars take time and effort to read and not very accurate. As most gas distribution systems rely solely on pressure to alter from primary to reserve cylinders, false low-pressure readings could cause lab personnel to take out containers with just as much as 25 % in the contents still inside.
Solution: CONCOA’s Intelligent Gas Distribution System IntelliSwitch II continuously monitors your reserve container’s pressure, using programmed software logic to ascertain if a container is actually empty or contains residual product. IntelliSwitch II 538 Series is the latest within the collection of computer-controlled gas distribution switchover systems using very accurate transducers to monitor both primary and reserve inlet pressures. Proprietary software logic uses these details to drastically reduce evaporation loss by switching to the reserve dewar to offer the gas to the instrument prior to the relief valve opens, drawing down pressure within the container to a programmed point, then returning to the key dewar. This “economizer function” can virtually eliminate losses within the reserve Cryogenic ISO Tank Container.
Additionally, when primary dewar pressure drops beneath the point at which the system switches to the reserve, IntelliSwitch II does not immediately conclude the container is empty. It waits a programmable period of time even though offering the system through the reserve, watches the strain reading in the primary. If the pressure rises 46dexkpky the switchover part of this time period, the pc concludes residual liquid was left in the container and switches returning to it to offer the instrument. It does this repeatedly till the dewar fails to create pressure higher than the programmable switchover point, from which time it switches on the reserve, and sounds a burglar alarm to indicate the principal is now truly empty. This “look-back feature” cuts down on the residual discarded when using dewars to lower than 2 to 3 percent.
By reducing evaporation loss and reducing the residual left in empty containers, CONCOA’s IntelliSwitch II optimizes the fee savings of employing Cryogenic Centrifugal Pump to provide gas to ICP or ICP/Mass Specs.