Monthly Archives: September 2016

Sterlitech is launching new stir bar assemblies for the HP4750 family of stirred cells. The new design has the following features and benefits:

• A strong magnet for better mixing
• Secure design to eliminate the risk of damage to membrane
• Complete disassembly for cleaning
• Composed of chemical resistant PTFE and SS316 parts

Stir bar assemblies are commonly used in dead-end filtration cells, such as HP4750, HP4750X, to induce turbulence at the membrane surface in order to reduce the membrane fouling. To browse our complete selection of stirred cells, parts and accessories, please visit https://www.sterlitech.com/stirred-cells.html

Researchers from the European Monitoring Center for Drugs and Drug Addiction are zeroing in on public toilets in Europe to identify drug use patterns across the continent. Over the past decade, sewage plant wastewater has been a top source for monitoring drug consumption. However, due to the rising number of new psychoactive substances on the market, scientists have had to come up with new ways to identify suspicious chemicals more effectively. In a recent publishing entitled “Assessing illicit drugs in wastewater”, the EMCDDA expounds on new methodologies for scanning through sewage water to identify drug use trends in different cities. Part of the report includes references to studies that sourced and analyzed wastewater directly from public toilets where drug use was thought to be common. According to the paper, this technique allows researchers to carry out more geographically detailed analyses as well as identify drugs whose uses are still unknown. Through the traditional

When particles of a known and defined size are removed via filtration, it is fairly easy to choose the right filter by simply selecting a pore size smaller than the particle. But what happens when you need to filter a very dirty solution that contains an innumerable amount of particle sizes? If a pore size too small is chosen, a cake layer of debris will form on the membrane surface and foul it completely. If too big of a pore size is selected, then a large portion of the solids will pass right through the filter. Because it could be easily overdone, it’s usually not a good idea to stack multiple filters in the same filter holder and process it all at once. So what is an effective solution to this problem?

Enter the world of pressure drop! Back in 1856, French hydrogeologist Henry Darcy figured out the physics behind fluid flow in a filter medium while he was working in Dijon, France (yes, also the little town that gave us great mustard). Henry figured out that in order

In 2015, the US Food and Drug Administration (FDA) signed off on new legislation to finalize the Food Safety Modernization Act (FSMA), which requires food and beverage manufacturers to be more proactive to minimizing food-borne contamination from microorganisms. The FDA now places more effort on the individual companies to test food products according to the new guidelines in various parts of the production process. These processes can be ideal places to draw fluid samples for bacterial capture and subsequent analysis. The use of membrane filters to evaluate bioburden in these types of liquids is the standard means of recovering and quantifying potentially harmful microorganisms. Does this sound like it makes for more work for the food processors in our communities? It might, but Sterlitech Corporation can help!

According to the new regulations, high-risk food producers will be inspected more frequently, will have to maintain more detailed records, and establish clear food safety

What is silt density index (SDI)?
Silt density index (SDI) estimates the quantity of suspended solids and colloids inside of water. SDI is measured following the ASTM D19.08 Standard Test Method for Silt Density Index (SDI) of Water, using a 0.45 micron membrane. SDI provides information about the fouling potential of water treatment equipment, including membrane filtration systems, and therefore is commonly used in their design and choice.

Is SDI a reliable fouling propensity parameter? How is it used?
SDI is a simple and helpful tool extensively used in pilot or large-scale treatment plants as a standard test to verify the fouling potential of RO and NF membranes. However, using SDI to estimate the fouling intensity of water treatment equipment has some limitations. Even though SDI is measured using a dead-end filtration unit, hydrodynamic conditions in dead-end filtration units are not representative of the hydrodynamic