1)  How do pH swings affect short term and long term performance of the unit, specifically accuracy and reliability (Our high end of TC would be 7,500-10,000 ppm)?  Would a larger pH range require different reagent concentrations?                   

Answer:  The QuickTOC, is a combustion analyzer that uses a combustion temperature of 1,200 degrees C and therefore will not be effected by pH swings.  When analyzing TC (Total Carbon) the QuickTOC requires no reagents. The analysis is a physical combustion between the carbon in the sample and the oxygen from the air, in the carrier gas, and not a chemical reaction that requires additional chemicals/reagents to complete.    The accuracy and the reliability of the QuickTOC, for analyzing TC at the concentration ranges you specify will  not be effected by pH swings.

2)  What air pressure (min and max) is required for the unit?                    

Answer: The QuickTOC is offered with it's own carrier gas generation system making it a self contained unit, however if you wish to supply your own carrier gas the unit will need a supply of CO2 free dry air at 1.2 bar pressure and 30 l/hr flow.

3) Will an air filter be required to remove oil and debris from plant instrument air or is one included in the unit?                 

Answer: If your company decided to use the LAR carrier gas generation system, then there would be no need for plant instrument air.  The only requirement for instrument air would be if your company decides to purge the unit and in this case the use of an oil and particle filter would be recommended.

4) How well does the unit (with the standard enclosure) perform in washdown situations?  Do any special precautions need to be taken?

Answer: The standard enclosure is rated to IP 55 which is equivalent to NEMA 13 which is not rated for preventing water ingress.  If it is placed in an area where washdown takes place then precautions would need to be taken to stop the analyzer being directly sprayed. The alternative would be to have the analyzer equipped with the optional NEMA 4X Stainless Steel enclosure.

5)  Can the unit handle multiple feed streams?

Answer: The QuickTOC has the capability, as standard, to run two independent sample streams, for just a small additional cost for the software license.  However, if more streams are needed than we can supply a sample sequencer that has the capability of analyzing up to eight streams, but we recommend a maximum of four streams as being reasonable for one analyzer to handle.

6)  What are the maintenance requirements for the unit?  What is the frequency of that maintenance?

Answer: The QuickTOC has a standard preventative maintenance schedule that should take no longer than 30 min per week.  The one item of maintenance that is always discussed with combustion TOC/TC analyzers is the frequency in which the furnace needs to be repacked due to salt build up in the reactor.  Since the QuickTOC uses a combustion temperature of 1,200 degrees C, the salt (NaCl) passes through the furnace and it is still a vapor at 1,200 C. This extends the time between maintenance on the furnace in most applications to between 6 to 12 months.

7) What reagents and concentrations are required?  What is the estimated  usage amount of reagents in a 1 year time frame?

Answer: As stated previously, the QuickTOC requires no reagents, however it uses DI/Distilled water to wash/clean the needle after each injection into the furnace.  The DI/Distilled Water consumption is 5 liters per month, so it would be a total consumption of 60 liters per year.

8)  Can the unit handle a pressurized feed line or does it require a ~0psig feed stream?  Conversely, can the unit handle a low pressure feed line (times when the pump may not necessarily be on)?

Answer: The QuickTOC has it's own internal peristaltic sample pump that is designed to pump sample from a low pressure stream, we recommend a sample pressure <5 psi.  We normally use a sample overflow pot at the side of the analyzer from which the sample is drawn from, and the sample if pressurized, has the pressure reduced to be delivered to the overflow pot.

9) What is the measured accuracy/drift of the unit?

Answer: The quoted accuracy of the QuickTOC is 2% full scale.  The drift is best measured as the time recommended between calibrations, and with the QuickTOC we recommend calibration only once per month.  This is due to the way in which the analyzer measures the raw data, the unit measures the CO2 peak area from the combustion, detecting the start and the end of each peak during the analysis.  As a result any drift that occurs from the detector is automatically compensated for.

10) Please provide literature regarding the Clog-Free Flowsampler.

Answer: We do not have specific literature on the FlowSampler, however, the unit is designed as a particle separator and uses sample flow through a 1" pipe to obtain the separation.  The sample flow required is 20 l/hr and the system needs a pressure free drain. However from our experience with samples from, "Corn Milling Plants", producing high fructose corn syrup we have not found a need for the FlowSampler.  We have over 60 Analyzer in use at this Corn Milling Application.

11) What are the requirements for feed temperature?

Answer: Sample temperature will not effect the analysis with the QuickTOC, however on saying that we do recommend that the sample temperature is maintained below 60 degrees C.

12) Is pre-filtering required on the feed stream?

Answer: We have not seen a need for sample filtering in "Corn Milling" samples, however the sample must not have particles that would block a 1/4" ID line.

13) What effects on the unit will happen during the summer months when ambient temperature possibly exceeds 35°C?

Answer: The main mother board (PC) is temperature protected and is designed to power down if the board temperature exceeds 60 degrees centigrade, the unit would regain power and start analyzing again once the board temperature drops below 60 degrees C..  To be able to make a recommendation in this case will require more details about the expected installation location.  We have installed QuickTOC's in boiler rooms but these have been in NEMA 4X housings and have been cooled by either "Vortex Coolers" or cabinet airconditioners.