environmental lab

When you flush the toilet do you ever think, “Man, all this good stuff is just going to waste?” Ok, probably not. But in the future your home or office may be partially heated by that human waste, thanks to geothermal sewage. What exactly is geothermal sewage, you cringe? It’s the process by which the heat from a wastewater line is repurposed to heat a nearby facility such as a hotel or apartment building. The heat transfer is accomplished by filtering solids from the wastewater and passes through a heat pump before reaching the building.

In China geothermal sewage has already been installed in a few buildings, including the Beijing Train Station. Now a wastewater treatment facility in Philadelphia is beginning the first US trial with this technology. It is a company in Philadelphia, NovaThermal Energy, that is making geothermal sewage possible by developing a proprietary filter material that can efficiently remove waste without requiring pretreatment.

Currently the technology requires that a target building be adjacent to large sewer mains, but if this pilot project is successful it could change our attitudes about sewage (and poop). David Henderson of XPV Capital in Toronto may have said it best: “Wastewater is a terrible name for wastewater. There are incredibly valuable resources in a wastewater flow: energy, nutrients, other materials, water itself.” It’s just a matter of separating the good from the bad.

Read this Forbes piece for more information

We recently updated our Standard method and Application guide to include more filter recommendations for environmental analysis applications. These additions include topics such as the EPA method for extracting oil and grease from water and the Field Leach Test method from the United States Geological Survey. New methods are in addition to our existing collection of procedures which includes topics like air sampling, bacteria counting, and silt density index.

The product recommendations that we provide with the methods are based on the requirements set forth by the procedure, as well as input from customers and suppliers.

Check out the updated Standard Method & Application Guide

This week the Occupational Safety and Health Administration (OSHA) fined a carbon steel foundry in Wisconsin $95,480 for willfully overexposing their workers to crystalline silica, a known carcinogen. Ironically, this news comes shortly after a group of citizens petitioned the Wisconsin Department of Natural Resources (DNS) to adopt more stringent rules governing emissions of respirable crystalline silica.

Crystalline silica is a particularly dangerous air pollutant because it is a basic component of soil, sand, brick, granite and other common materials. As a byproduct of many everyday industrial processes like mining, construction, and glass manufacturing, it is a ubiquitous presence for some workers. Industrial processes that involve abrasive blasting or the use of sand and quartz are also sources of crystalline silica exposure, which is why many of these workers are concerned over the increasing popularity of fracking in their state. The hydraulic fracturing (AKA “Fracking”) process involves fracturing rock layers with a fluid that includes sand or ceramic material in order to extract the gas underneath. As you can tell from the description, stirring up compressed rock dust and sand particles is a definite health concern, so it’s good to see those at risk aware of it and addressing the matter.

The petitioners are asking the Wisconsin DNS to classify respirable crystalline silica as a hazardous air pollutant under their air toxics rule. Furthermore, the petitioners recommend that the DNS comply with the standard set by the State of California Office of Environmental Health Hazard Assessment which dictates a limit of 3 micrograms per cubic meter and requires consistent monitoring and enforcement.

Determining the concentration of crystalline silica and amorphous silica by the National Institute for Occupational Safety and Health (NIOSH) standards requires capturing particulates from an air sample on a 0.45 micron, 25 mm diameter Silver Membrane Filter and then analyzing the particulate matter for silica using X-Ray diffraction (XRD). See NIOSH methods 7500 and 7501 for the complete procedure.

Read the full petition by Wisconsin citizens here.
Also see this report on silica from the Wisconsin DNS.

The Environmental Protection Agency announced last week that they are planning to develop standards for wastewater discharges produced by natural gas extraction from underground coalbed and shale formations (a process commonly referred to as “Fracking”). This method of extraction involves fracturing rock formations by injecting them with a pressurized fluid consisting mostly of water, a little bit of sand, and some chemical additives as well. The debate over the possible environmental consequences of fracking is a hot button issue right now, and since its popularity has grown to the point where it now accounts for about 15% of all natural gas production in the US, it is understandable that the EPA wants to look into setting some uniform regulations.

Any potential EPA standards in this area can be broken down into two areas: shale gas standards and coalbed methane standards. In shale gas extraction, wastewater is prohibited from being discharged into waterways. Instead, it is either recycled back into use or sent to a treatment plant. Unfortunately, many of these treatment plants are not properly equipped to handle shale gas wastewater so the EPA will look into standards that could be implemented on wastewater before it reaches the treatment plant.

Creating a coalbed methane standard for wastewater treatment is a little bit trickier, since there aren’t any national standards for it yet. Currently it is up to individual states to regulate where the wastewater is discharged and what pre-treatment standards to follow. The EPA is hoping to address the matter by creating a uniform standard for the whole nation.

Based on the current EPA schedule, a proposed rule should come in 2013 for coalbed methane and 2014 for shale gas. This is to allow the EPA time to consult with stakeholders and allow for public comment.

You can read the full announcement from the EPA here.

The simple act of machine washing our clothes may be causing serious environmental damage, according to a new study from University College Dublin. A research team led by Dr. Mark Browne has traced a path from washing machine wastewater to abnormally high concentrations of microplastic debris found all over the world. The problem arises because the synthetic fibers that many of today’s clothes are made of, polyester and acrylic, get rinsed by the machine. While we may not notice it, one cycle can strip as much 1,900 fibers off each piece of synthetic clothing! These dangerous fibers eventually make their way to the ocean and wash up on our beaches. Research also shows that the pollutants are eaten by mussels and locusts, which can then work their way up the food chain to humans.

As a part of this study Dr. Browne’s team investigated 18 sites on six continents and through forensic analysis was able to match the proportions of polyester and acrylic fiber present in these sites with their proportions in clothing. They also found a correlation between sites with greater-than-average concentrations of microplastics and their exposure to washing machine wastewater.

Microplastic debris doesn’t get a lot of attention now in the environmental community, but as the human population grows and synthetic fibers become more commonplace, they have the potential to be a major concern in the future. Since it is likely that any solution to the problem will include standard or experimental methods of wastewater treatment, including filtration (see Flat Sheet Membranes), we’ll continue to look out for possible cures.

Read the full study from the ACS Journal of Environmental Science & Technology
Learn more about the work of Dr. Browne

In searching for new weapons in their fight against the destructive mountain pine beetle, scientists at the USDA Forest Service are experimenting using filtration techniques to create more effective insecticide treatment. It is estimated that 8% of forests in the United States are at risk to insect or disease outbreaks; among this percentage the mountain pine beetle is considered the biggest threat.

It’s necessary to find new solutions to protect these trees because of concerns about the future availability of one of the most commonly used insecticide chemicals, carbaryl, for environmental reasons. A study published this year examined the effectiveness of different concentrations of carbaryl along with two other known insecticides, cyantraniliprole and Cyazypyr (30 Scrabble points!).

For this experiment the researchers performed two different assays, one involved exposing the beetles to insecticide with filter paper and one through a topical treatment. For both tests they used 1 mL of various concentrations of the insecticides along with 934-AH filter paper (1.5 micron pore size, 90 mm diameter) stored in a sterile petri dish and dried in a fume hood.

In the filter paper assay, small holes were drilled into the petri dish to provide ventilation and captured beetles were placed on the filter paper. The health of the beetles was then assessed at regular intervals to determine the effectiveness of each insecticide concentration. In the topical assessment, the insecticide was applied directly onto the beetles which were then placed on top of the filter discs.

The results of the filter paper assays, which the authors believes more closely approximates field conditions than topical assays, found that is possible that much smaller amounts of carbaryl could be effective in the field, which is good news for the environment as concerns over the toxicity of this chemical have grown. As such, the authors recommend that smaller concentrations of carbaryl be tried in the field. Take that, pesky beetles!

Read the full report here

Cruising around the Scandinavian coastline in November might not sound like the most ideal place to conduct an environmental impact study, but for Norway’s Institute of Marine Research it was necessary in order to investigate the levels of anthropogenic particles in the Skagerrak strait. As you can imagine, this setting presented some unique challenges for the research team. In order to gather and analyze microscopic samples from this body of water, which is located between Norway, Denmark and Sweden, researchers had to come up with some new sampling methods and fashion their own equipment to solve problems that had plagued previous studies.

Norwegian Researchers Hard at Work^

One key obstacle that these scientists needed to overcome was how to distinguish between anthropogenic particles, which are man-made bits of matter that impact the environment (i.e. oil-spill droplets, asphalt, rubber tire wear, fly ash), from those particles with similar characteristics which appear naturally (volcanic ash, peat). To make this distinction, the samples were subjected to morphology analysis of their color and texture to first determine their origin before being counted.

The second major challenge was how to prevent contamination, which is easier said than done considering the harsh and unpredictable nature of the sea. One of the steps the researchers took to solve this was to develop control samples, free of any contaminants, which they could actually bring on board the ship with them. To further reduce the potential of contaminating samples, they also created new methodology and constructed their own customized sampling apparatus.

You can see a schematic of the sampling equipment the Institute researchers built in their published study. Their setup involved a submersible water pump that was positioned inside a waterproof case connected to the sampling filter (10 μm hydrophobic polycarbonate membrane filters, along with a 30 μm square mesh nylon filter as a support) which was placed directly in the sea. To protect the filter from wave turbulence they modified one of our filter holders (this one) with a new outlet fitting and a larger, semi-enclosed inlet with a smooth surface. The filters were also placed in protective holders before and after filtration for protection and to reduce the risk of contamination. As an added protective measure, the filter apparatus was ultrasonically cleaned prior to use. The entire sampling apparatus was held 2 meters outside the boat (to further prevent contamination) and the sampling depth was limited to between 0.1 and 1.5 meters to protect it from large waves.

While it will take many more studies before conclusions can be drawn about the state of this particular body of water, the scientists were encouraged by the results of the new methodology they created. They note in the conclusion how these improvements have standardized the sampling and reduced the risk of contamination. The scientists also suggest that this sampling equipment could be adapted for larger particles.

To read the full study, visit here.
^Image from Survey of microscopic anthropogenic particles in Skagerrak. Lysekil and Flødevigen 2010-11-20, Institute of Marine Research.

After our last post discussing how experiments with carbon nanotubes (CNT’s) might greatly improve the effectiveness of reverse osmosis desalination now comes a new report from the Institute of Physics that shows researchers are getting closer to making this a reality. Already over a billion people do not have regular access to clean water and the problem will likely get worse as the demand for drinkable water is expected to grow dramatically in the near future. With natural sources increasingly scarce, this urgent need means there is an intense global interest in any potentially viable forms of water purification.

Right now the main issues preventing RO desalination on a large-scale basis are that the membranes used to perform seawater to freshwater separation do not remove salt ions with enough efficiency and they also require great amounts of energy (and therefore expense) in order to purify the water. Jason Reese, a Professor of Thermodynamics and Fluid Mechanics at the University of Strathclyde and also the author of this report, states, “The holy grail of reverse-osmosis desalination is combining high water-transport rates with efficient salt-ion rejection.” Incredibly, these little carbon nanotubes may be able to satisfy both of these requirements for widespread adoption.

Early tests and simulations have shown that CNT membranes could have water permeability that is 20 times greater than today’s materials. Additionally, carbon nanotubes can be chemically tailored to better reject salt ions, thus improving upon the desalination process in multiple key areas.

While it is still early, these features are promising enough that scientists such as Professor Reese feel it is a very real possibility that this application of nanotechnology could be used to curtail our growing water demand.

Read more about this report here.

An increase in salinity levels at the North Reverse Osmosis Water Plant in Kill Devil Hills (yes, that’s the town name) that had been creating stress for some local officials has been explained in a recent study. Researchers from nearby Duke University found that the rising salinity levels at this coastal aquifer are the result of fossil seawater and not seawater intrusion, as had been feared. Since the well’s installation in the late 1980’s salinity has more than doubled from about 1,000 mg/L to about 2,500 mg/L. There was much cause for relief however, when researchers were able to attribute the rise to fossilized seawater and not to seawater leaking in from the coast.

According to the director of the study, Duke Professor Avner Vengosh, knowing the source of the salinity increase is important because fossil seawater raises salinity, “At a relatively slow and steady rate that is more manageable and sustainable than the rapid increase we’d see if there was modern-day seawater intrusion.” As a result of this study the community will be able to rely on this aquifer for decades to come without having to resort to more expensive seawater desalination techniques which require more energy and advanced filtration methods.

Current treatment for groundwater desalination includes the use of reverse osmosis (RO) membranes to separate dissolved salts from potable water. Even with the rising salinity level these membranes remove around 96 to 99 percent of the dissolved salts. RO membranes also remove between 16 and 42 percent of the boron and 54 to 75 percent of the arsenic from the groundwater. Additional treatment following reverse osmosis desalination continues to remove arsenic until it is within safe drinking levels (10 parts per billion, according to the EPA).

Because seawater consistently has more salt than groundwater it requires more energy to treat, and therefore the cost is higher. Per this report on desalination from the Pacific Institute, “Energy is the single largest variable cost for a desalination plant, varying from one-third to more than one-half the cost of produced water.” The report also states, “At these percentages, a 25% increase in energy cost would increase the cost of produced water by 11% (for RO plants).” In looking at these percentages, it’s easy to see why the plant was concerned about seawater intrusion. Thanks to this research, the local citizens can drink easier knowing they have a supply of healthy, affordable water for a long time to come.

Click here to learn more about this case.

Here’s further evidence that monitoring your company's waste output is something you should probably keep an eye on…

Yesterday the former environmental, health & safety manager for AMCAN Beverages, Inc. (A subsidiary of Coca-Cola) pled guilty to falsifying reports about their plant's wastewater discharge. He now faces up to 3 years in prison and/or upwards of $250,000 in fines for directing employees to dilute wastewater samples before they were sent for off-site testing and then reporting on the tampered results.

The company was caught when the City of American Canyon’s own wastewater treatment plant staterd experiencing operational problems relating to Biological Oxygen Demand (BOD) and Total Suspended Solids (TSS) measurements and began a covert investigation into industrial discharges in the area, leading them to AMCAN.

If only Captain Planet was still around to call on, he'd take pollution down to zero...

Read more details on the case here.

And yes, we do offer plenty of different products for TSS measurements as well as bench scale systems for municipal/industrial waste and wastewater purification.