Frequently Asked Questions (FAQ) about VSEP
Q: How many VSEPs are there in service?
A: There are over 400 VSEP systems in 19 different countries around the world.
Q: Do you make your own membranes?
A: No, New Logic buys membranes from all of the leading manufacturers and modifies them for use in the VSEP system. We currently use over 200 different membranes.
Q: Can you use ceramic or steel membranes in a VSEP system?
A: No, VSEPs employ only polymeric membranes.
Q: What comes with a VSEP system?
A: The standard VSEP system comes with the VSEP vibratory drive system, filter pack, feed pump(s), clean‐in‐place system, automated air‐actuated valves, all interconnecting piping within our system and a programmable logic controller (PLC) with a touch‐screen interface. All of this is skid‐mounted and tested on water prior to shipment.
Q: What is the installation cost multiplier for a VSEP system?
A: Since the system is all skid‐mounted, the installation costs are minimal as compared to competing technologies. A good rule of thumb is a 1.2 multiplier.
Q: What flow rate can be processed with VSEP?
A: VSEP systems are modular, can be arranged in parallel, and as such can theoretically process any flow rate. The feed stream is fed to a manifold (header) and the feed is distributed evenly over the array.
Q: What membrane type is good for what?
A: Reverse Osmosis = Dissolved metals, salts removal, high purity water Nano‐Filtration = BOD/COD reduction, dissolved solids, wastewater Ultrafiltration = Suspended solids removal, product dewatering Microfiltration = Large suspended solids removal, dewatering.
Q: What is the maximum operating temperature of a VSEP?
A: The maximum temperature is determined by the membrane. See the membrane list for particulars. There is a high temperature VSEP system which can operate at 130°C with a Teflon membrane.
Q: What pH can the membranes tolerate?
A: Again, this is always membrane‐dependent. Generally speaking, the more open the membrane, the better it is at extreme pH tolerance. We have filtered 54% phosphoric acid and we’ve filtered 50% sodium hydroxide. See the membrane list for particulars.
Q: Can your membranes tolerate chlorine and/or other strong oxidizers?
A: This is another membrane‐dependent factor. Some can take a little, others can take a lot. Most nano and RO membranes can’t tolerate much chlorine at all. We can easily overcome this problem by dosing the feed with a small amount of a reducing agent such as sodium metabisulfite. Membranes can take other oxidizers such as peroxides (i.e. NLR 550) but require great care in use.
Q: How often do you have to clean the membranes?
A: Anywhere from once a day to once a month. Average is once or twice a week.
Q: How high can you concentrate to in a VSEP system?
A: The record is 76% solids, which has been done on TiO2? . The real limitation is the gel point of a given feed material (suspended solids) or where the osmotic pressure is too high to overcome at 1000psi (dissolved solids).
Q: What is the maximum dissolved solids level (TDS) you can feed to a VSEP system?
A: This really only applies to RO applications. For practical purposes, the maximum TDS in the feed should be less than 10% (100,000 ppm).
Q: What is the maximum suspended solids level (TSS) you can feed to a VSEP system?
A: About 50% starting
Q: What is the pressure drop across the VSEP filter pack?
A: The answer is about 1 psi, however the question is really not germane to our system. The reason people ask this question is because it’s important in a cross‐flow membrane filtration system, as this is the major source of pump energy loss. In a VSEP system, the shear comes from the vibration, not the pump. 99% of the pressure drop occurs at the concentrate exit valve, which we can control to be whatever we want.
Customer Lab Testing FAQ
Q: How much does the standard lab test cost?
A: $1,200 ($1,800 or more for hazardous or multi‐stage tests)
Q: What do I get for my $1,200?
A: 5‐day test (membrane selection, process parameter optimization, concentration study, cleaning study) a complete report, some basic analytical and samples of the resulting permeate and concentrate. Extensive analytical testing is available for an additional charge.
Q: How much sample do you need?
A: A bare minimum of 50 litres. We would prefer to get 100 litres.
Q: What about shipping?
A: Customers are responsible for all shipping costs. If a sample is biologically active, the sample should be chilled and shipped overnight to New Logic. In such cases, you must closely coordinate the shipping date with the Lab staff to ensure a machine is available upon arrival of the sample.
Q: How long does all of this take?
A: There is typically about a one‐week wait from the time the sample arrives and the start of testing. The test takes about five days to complete. After the testing is completed, the report is generated about one to two weeks later. It’s about a month from start to finish.
Q: I can’t send my sample to your facility for testing. Can we do a lab test here at my plant?
A: Yes. It’s considerably more expensive, however, as you have to lease a pilot machine.
Q: How long will it take to get a pilot machine on site?
A: Typically within a month. We have to coordinate the machine as well as the technician.
Q: Do you have explosion‐proof pilot machines?
A: Yes, we have a Class I Div II machine available. The cost for this system is quoted on a case by case basis.
Q: What is the footprint of the pilot system?
A: Approximately 3’ x 6’ (0.91m x 1.8m)
Q: What is the size of the pilot system piping?
A: ½ inch (127mm)
Q: What is the temperature limitation of the pilot system?
A: 60‐100°C (membrane dependent)