Tag Archives: petroleum

Let them (Rice University scientists) show you how to restore oil-soaked soil

I did not want to cash in (so to speak) on someone else’s fun headline so I played with it. Hre is the original head, which was likely written by either David Ruth or Mike Williams at Rice University (Texas, US), “Lettuce show you how to restore oil-soaked soil.”

A February 1, 2019 news item on ScienceDaily on the science behind lettuce and oil-soaked soil,

Rice University engineers have figured out how soil contaminated by heavy oil can not only be cleaned but made fertile again.

How do they know it works? They grew lettuce.

Rice engineers Kyriacos Zygourakis and Pedro Alvarez and their colleagues have fine-tuned their method to remove petroleum contaminants from soil through the age-old process of pyrolysis. The technique gently heats soil while keeping oxygen out, which avoids the damage usually done to fertile soil when burning hydrocarbons cause temperature spikes.

Lettuce growing in once oil-contaminated soil revived by a process developed by Rice University engineers. The Rice team determined that pyrolyzing oil-soaked soil for 15 minutes at 420 degrees Celsius is sufficient to eliminate contaminants while preserving the soil’s fertility. The lettuce plants shown here, in treated and fertilized soil, showed robust growth over 14 days. Photo by Wen Song

A February 1, 2019 Rice University news release (also on EurekAlert), which originated the news item, explains more about the work,

While large-volume marine spills get most of the attention, 98 percent of oil spills occur on land, Alvarez points out, with more than 25,000 spills a year reported to the Environmental Protection Agency. That makes the need for cost-effective remediation clear, he said.

“We saw an opportunity to convert a liability, contaminated soil, into a commodity, fertile soil,” Alvarez said.

The key to retaining fertility is to preserve the soil’s essential clays, Zygourakis said. “Clays retain water, and if you raise the temperature too high, you basically destroy them,” he said. “If you exceed 500 degrees Celsius (900 degrees Fahrenheit), dehydration is irreversible.

The researchers put soil samples from Hearne, Texas, contaminated in the lab with heavy crude, into a kiln to see what temperature best eliminated the most oil, and how long it took.

Their results showed heating samples in the rotating drum at 420 C (788 F) for 15 minutes eliminated 99.9 percent of total petroleum hydrocarbons (TPH) and 94.5 percent of polycyclic aromatic hydrocarbons (PAH), leaving the treated soils with roughly the same pollutant levels found in natural, uncontaminated soil.

The paper appears in the American Chemical Society journal Environmental Science and Technology. It follows several papers by the same group that detailed the mechanism by which pyrolysis removes contaminants and turns some of the unwanted hydrocarbons into char, while leaving behind soil almost as fertile as the original. “While heating soil to clean it isn’t a new process,” Zygourakis said, “we’ve proved we can do it quickly in a continuous reactor to remove TPH, and we’ve learned how to optimize the pyrolysis conditions to maximize contaminant removal while minimizing soil damage and loss of fertility.

“We also learned we can do it with less energy than other methods, and we have detoxified the soil so that we can safely put it back,” he said.

Heating the soil to about 420 C represents the sweet spot for treatment, Zygourakis said. Heating it to 470 C (878 F) did a marginally better job in removing contaminants, but used more energy and, more importantly, decreased the soil’s fertility to the degree that it could not be reused.

“Between 200 and 300 C (392-572 F), the light volatile compounds evaporate,” he said. “When you get to 350 to 400 C (662-752 F), you start breaking first the heteroatom bonds, and then carbon-carbon and carbon-hydrogen bonds triggering a sequence of radical reactions that convert heavier hydrocarbons to stable, low-reactivity char.”

The true test of the pilot program came when the researchers grew Simpson black-seeded lettuce, a variety for which petroleum is highly toxic, on the original clean soil, some contaminated soil and several pyrolyzed soils. While plants in the treated soils were a bit slower to start, they found that after 21 days, plants grown in pyrolyzed soil with fertilizer or simply water showed the same germination rates and had the same weight as those grown in clean soil.

“We knew we had a process that effectively cleans up oil-contaminated soil and restores its fertility,” Zygourakis said. “But, had we truly detoxified the soil?”

To answer this final question, the Rice team turned to Bhagavatula Moorthy, a professor of neonatology at Baylor College of Medicine, who studies the effects of airborne contaminants on neonatal development. Moorthy and his lab found that extracts taken from oil-contaminated soils were toxic to human lung cells, while exposing the same cell lines to extracts from treated soils had no adverse effects. The study eased concerns that pyrolyzed soil could release airborne dust particles laced with highly toxic pollutants like PAHs.

”One important lesson we learned is that different treatment objectives for regulatory compliance, detoxification and soil-fertility restoration need not be mutually exclusive and can be simultaneously achieved,” Alvarez said.

Here’s a link to and a citation for the paper,

Pilot-Scale Pyrolytic Remediation of Crude-Oil-Contaminated Soil in a Continuously-Fed Reactor: Treatment Intensity Trade-Offs by Wen Song, Julia E. Vidonish, Roopa Kamath, Pingfeng Yu, Chun Chu, Bhagavatula Moorthy, Baoyu Gao, Kyriacos Zygourakis, and Pedro J. J. Alvarez. Environ. Sci. Technol., 2019, 53 (4), pp 2045–2053 DOI: 10.1021/acs.est.8b05825 Publication Date (Web): January 25, 2019

Copyright © 2019 American Chemical Society

This paper is behind a paywall.

Cellulose nanocrystals (CNC), also known as nanocrystalline cellulose (NCC), and toxicity; some Celluforce news; anti-petroleum extremists

The February 2015 issue of Industrial Biotechnology is hosting a special in depth research section on the topic of cellulose nanotechnology. A Feb. 19, 2015 news item on Phys.org features a specific article in the special section (Note: A link has been removed),

Novel nanomaterials derived from cellulose have many promising industrial applications, are biobased and biodegradable, and can be produced at relatively low cost. Their potential toxicity—whether ingested, inhaled, on contact with the skin, or on exposure to cells within the body—is a topic of intense discussion, and the latest evidence and insights on cellulose nanocrystal toxicity are presented in a Review article in Industrial Biotechnology.

Maren Roman, PhD, Virginia Tech, Blacksburg, VA, describes the preparation of cellulose nanocrystals (CNCs) and highlights the key factors that are an essential part of studies to assess the potential adverse health effects of CNCs by various types of exposure. In the article “Toxicity of Cellulose Nanocrystals: A Review” , Dr. Roman discusses the current literature on the pulmonary, oral, dermal, and cytotoxicity of CNCs, provides an in-depth view on their effects on human health, and suggests areas for future research.

There has been much Canadian investment both federal and provincial in cellulose nanocrystals (CNC). There’s also been a fair degree of confusion regarding the name. In Canada, which was a research leader initially, it was called nanocrystalline cellulose (NCC) but over time a new term was coined cellulose nanocrystals (CNC). The new name was more in keeping with the naming conventions for other nanoscale cellulose materials such as  cellulose nanofibrils, etc. Hopefully, this confusion will resolve itself now that Celluforce, a Canadian company, has trademarked NCC. (More about Celluforce later in this post.)

Getting back to toxicity and CNC, here’s a link to and a citation for Maron’s research paper,

Toxicity of Cellulose Nanocrystals: A Review by Roman Maren. Industrial Biotechnology. February 2015, 11(1): 25-33. doi:10.1089/ind.2014.0024.

The article is open access at this time. For anyone who doesn’t have the time to read it, here’s the conclusion,

Current studies of the oral and dermal toxicity of CNCs have shown a lack of adverse health effects. The available studies, however, are still very limited in number (two oral toxicity studies and three dermal toxicity studies) and in the variety of tested CNC materials (CelluForce’s NCC). Additional oral and dermal toxicity studies are needed to support the general conclusion that CNCs are nontoxic upon ingestion or contact with the skin. Studies of pulmonary and cytotoxicity, on the other hand, have yielded discordant results. The questions of whether CNCs have adverse health effects on inhalation and whether they elicit inflammatory or oxidative stress responses at the cellular level therefore warrant further investigation. The toxicity of CNCs will depend strongly on their physicochemical properties—in particular, surface chemistry, including particle charge, and degree of aggregation, which determines particle shape and dimensions. Therefore, these properties—which in turn depend strongly on the cellulose source, CNC preparation procedure, and post-processing or sample preparation methods, such as lyophilization, aerosolization, sonication, or sterilization—need to be carefully measured in the final samples.

Another factor that might affect the outcomes of toxicity studies are sample contaminants, such as endotoxins or toxic chemical impurities. Samples for exposure tests should therefore be carefully analyzed for such contaminants prior to testing. Ideally, because detection of toxic chemical contaminants may be difficult, control experiments should be carried out with suitable blanks from which the CNCs have been removed, for example by membrane filtration. Moreover, especially in cytotoxicity assessments, the effect of CNCs on pH and their aggregation in the cell culture medium need to be monitored. Only by careful particle characterization and exclusion of interfering factors will we be able to develop a detailed understanding of the potential adverse health effects of CNCs.

If I understand this rightly, CNC seems safe (more or less) when ingested orally (food/drink) or applied to the skin (dermal application) but inhalation seems problematic and there are indications that this could lead to inflammation of lung cells. Other conclusions suggest both the source for the cellulose and CNC preparation may affect its toxicity. I encourage you to read the whole research paper as this author provides good explanations of the terms and summaries of previous research, as well as, some very well considered research.

Here’s more about Industrial Biotechnology’s special research section in the February 2015 issue, from a Feb. 19, 2015 Mary Ann Liebert publishers press release (also on EurekAlert*),

The article is part of an IB IN DEPTH special research section entitled “Cellulose Nanotechnology: Fundamentals and Applications,” led by Guest Editors Jose Moran-Mirabal, PhD and Emily Cranston, PhD, McMaster University, Hamilton, Canada. In addition to the Review article by Dr. Roman, the issue includes Reviews by M. Rose, M. Babi, and J. Moran-Mirabal (“The Study of Cellulose Structure and Depolymerization Through Single-Molecule Methods”) and by X.F. Zhao and W.T. Winter (“Cellulose/cellulose-based nanospheres: Perspectives and prospective”); Original Research articles by A. Rivkin, T. Abitbol, Y. Nevo, et al. (“Bionanocomposite films from resilin-CBD bound to cellulose nanocrystals), and P. Criado, C. Fraschini, S. Salmieri, et al. (“Evaluation of antioxidant cellulose nanocrystals and applications in gellan gum films”); and the Overview article “Cellulose Nanotechnology on the Rise,” by Drs. Moran-Mirabal and Cranston.

Meanwhile Celluforce announces a $4M ‘contribution’ from Sustainable Development Technology Canada (SDTC), from a Feb. 16, 2015 Celluforce news release,

CelluForce welcomes the announcement by Sustainable Development Technology Canada (SDTC) of a contribution of $4.0 million to optimize the extraction process of Nanocrystaline Cellulose (NCC) from dry wood pulp and develop applications for its use in the oil and gas sector. The announcement was made in Quebec City today [Feb. 16, 2015] by the Honourable Greg Rickford, Minister of Natural Resources and Minister for the Federal Economic Development Initiative for Northern Ontario.

NCC is a fundamental building block of trees that can be extracted from the forest biomass and has unique properties that offer a wide range of potential applications. Measured in units as small as nanometres, these tiny structures have strength properties comparable to steel and will have uses in a variety of industrial sectors. In particular, NCC is touted as having the potential to significantly advance the oil and gas industry.

Our Government is positioning Canada as a global leader in the clean technology sector by supporting innovative projects aimed at growing our economy while contributing to a cleaner environment,” said the Honourable Greg Rickford, Canada’s Minister of Natural Resources. [emphasis mine] “By developing our resources responsibly, exploring next-generation transportation and advancing clean energy technology, the projects announced today will create jobs and improve innovation opportunities in Quebec and across Canada.”

“World-class research led to the development of this ground breaking extraction process and placed Canada at the leading edge of NCC research”, stated René Goguen, Acting President of CelluForce Inc. “This announcement by SDTC sets the stage for the pre-commercial development of applications that will not only support Canada’s forest sector but also the oil and gas sector, both of which are important drivers of the Canadian economy.”

This project will further improve and optimize the process developed by CelluForce to extract nanocrystalline cellulose (CelluForce NCC™) from dry wood pulp. In addition to improving the extraction process, this project will investigate additional applications for the oil-and-gas industry such as cementing using this renewable forestry resource.

There’s very little information in this news release other than the fact that CelluForce’s $4M doesn’t need to be repaid seeing it’s described as a ‘contribution’ rather than an investment. The difference between a contribution and a grant, which is what these funds used to be called, somewhat mystifies me unless this is a translation issue.

As for the news release content, it is remarkably scant. This $4M will be spent on improving the extraction process and on applications for the oil and gas industry. Neither the improvements nor the possible applications are described. Hopefully, the government has some means of establishing whether or not those funds (sorry, the contribution) were used for the purposes described.

I am glad to see this in this news release, “Our Government is positioning Canada as a global leader in the clean technology sector …” although I’m not sure how it fits with recent attempts to brand environmentalists as part of an ‘anti-petroleum’ movement as described in a Feb. 19, 2015 post by Glyn Moody for Techdirt (Note: A link has been removed),

As Techdirt has been warning for some time, one of the dangers with the flood of “anti-terrorist” laws and powers is that they are easily redirected against other groups for very different purposes. A story in the Globe and Mail provides another chilling reminder of how that works:

The RCMP [Royal Canadian Mounted Police] has labelled the “anti-petroleum” movement as a growing and violent threat to Canada’s security, raising fears among environmentalists that they face increased surveillance, and possibly worse, under the Harper government’s new terrorism legislation.

As the Globe and Mail article makes clear, environmentalists are now being considered as part of an “anti-petroleum” movement. That’s not just some irrelevant rebranding: it means that new legislation supposedly targeting “terrorism” can be applied.

It seems logically incoherent to me that the government wants clean tech while condemning environmentalists. Whether or not you buy climate change science (for the record, I do), you have to admit that we are running out of petroleum. At heart, both the government and the environmentalists have to agree that we need new sources for fuel. It doesn’t make any sense to spend valuable money, time, and resources on pursuing environmentalists.

This business about the ‘anti-petroleum’ movement reminds me of a copyright kerfuffle including James Moore, currently the Minister of Industry, and writer Cory Doctorow. Moore, Minister of Canadian Heritage at the time, at some sort of public event, labeled Doctorow as a ‘radical extremist’ regarding his (Doctorow’s) views on copyright. The comments achieved notoriety when it appeared that Moore and the organizers denied the comments ever took place. The organizers seemed to have edited the offending video and Moore made public denials. You can read more about the incident in my June 25, 2010 post. Here’s an excerpt from the post which may explain why I feel there is a similarity,

… By simultaneously linking individuals who use violence to achieve their ends (the usual application for the term ‘radical extremists’) to individuals who are debating, discussing, and writing commentaries critical of your political aims you render the term into a joke and you minimize the violence associated with it.

Although with ‘anti-petroleum’, it seems they could decide any dissension is a form of violence. It should be noted that in Canada the Ministry of Industry, is tightly coupled with the Ministry of Natural Resources since the Canadian economy has been and continues to be largely resource-based.

For anyone interested in CelluForce and NCC/CNC, here’s a sampling of my previous posts on the topic,

CelluForce (nanocrystalline cellulose) plant opens (Dec. 15, 2011)

Double honours for NCC (ArboraNano and CelluForce recognized) (May 25, 2012)

You say nanocrystalline cellulose, I say cellulose nanocrystals; CelluForce at Japan conference and at UK conference (Oct. 15, 2012)

Designing nanocellulose (?) products in Finland; update on Canada’s CelluForce (Oct. 3, 2013) Note: CelluForce stopped producing NCC due to a growing stockpile.

There’s a lot more about CNC on this blog* should you care to search. One final note, I gather there’s a new interim boss at CelluForce, René Goguen replacing Jean Moreau.

* EurekAlert link added Feb. 20, 2015.

* ‘on the CNC blog’ changed to ‘about CNC on this blog’ on March 4, 2015.

“Sensational” 15% can become up to 50% oil recovery rate from dead oil wells with nanoparticle-enhanced water

Texas, the Middle East, and/or Alberta leap to mind before Norway and China when one thinks of research into oil extraction, which makes this June 14, 2013 news item on Nanwerk about a Norway-China collaboration particularly intriguing,

When petroleum companies abandon an oil well, more than half the reservoir’s oil is usually left behind as too difficult to recover. Now, however, much of the residual oil can be recovered with the help of nanoparticles and a simple law of physics.

Oil to be recovered is confined in tiny pores within rock, often sandstone. Often the natural pressure in a reservoir is so high that the oil flows upwards when drilling reaches the rocks containing the oil.

In order to maintain the pressure within a reservoir, oil companies have learned to displace the produced oil by injecting water. This water forces out the oil located in areas near the injection point. The actual injection point may be hundreds or even thousands of metres away from the production well.

Eventually, however, water injection loses its effect. Once the oil from all the easily reached pores has been recovered, water begins emerging from the production well instead of oil, at which point the petroleum engineers have had little choice but to shut down the well.

The petroleum industry and research community have been working for decades on various solutions to increase recovery rates. One group of researchers at the Centre for Integrated Petroleum Research (CIPR) in Bergen, collaborating with researchers in China, has developed a new method for recovering more oil from wells – and not just more, far more. [emphasis mine]

The Chinese scientists had already succeeded in recovering a sensational 15 per cent of the residual oil in their test reservoir when they formed a collaboration with the CIPR researchers to find out what had actually taken place down in the reservoir. Now the Norwegian partner in the collaboration has succeeded in recovering up to 50 per cent of the oil remaining in North Sea rock samples.

The ?, 2013 article (Nanoparticles helping to recover more oil) by Claude R. Olsen/Else Lie. Translation: Darren McKellep/Carol B. Eckmann for the Research Council of Norway, which originated the news item, explains what is left after the easy oil has been extracted and how this news technique squeezes more oil out of the well,

Water in an oil reservoir flows much like the water in a river, accelerating in narrow stretches and slowing where the path widens.

When water is pumped into a reservoir, the pressure difference forces the water away from the injection well and towards the production well through the tiny rock pores. These pores are all interconnected by very narrow tunnel-like passages, and the water accelerates as it squeezes its way through these.

The new method is based on infusing the injection water with particles that are considerably smaller than the tunnel diameters. When the particle-enhanced water reaches a tunnel opening, it will accelerate faster than the particles, leaving the particles behind to accumulate and plug the tunnel entrance, ultimately sealing the tunnel.

This forces the following water to take other paths through the rock’s pores and passages – and in some of these there is oil, which is forced out with the water flow. The result is more oil extracted from the production well and higher profits for the petroleum companies.

The article writers do not provide a description of the nanoparticles but they do describe the genesis of this Norwegian-Sino collaboration,

The idea for this method of oil recovery came from the two Chinese researchers Bo Peng and Ming yuan Li who completed their doctorates in Bergen 10 and 20 years ago, respectively. The University of Bergen and China University of Petroleum in Beijing have been cooperating for over a decade on petroleum research, and this laid the foundation for collaboration on understanding and refining the particle method.

At first it was not known if the particles could be used in seawater, since the Chinese had done their trials with river water and onshore oilfields. Trials in Bergen using rock samples from the North Sea showed that the nanoparticles also work in seawater and help to recover an average of 20?30 per cent, and up to 50 per cent, more residual oil.