Tveskaeg article: The Right Frequency

NanoNord has big expectations for their online NMR-sensor for determination of different matters in sewage sludge. The sensor is not only contributing to optimizing the processes of biogas production; the ambition is to deliver a platform with countless options, which will revolutionize the water processing industry.

Sewage from waste water treatment plants (WWTP) can be recognized as an asset that can reduce the consumption of energy within these facilities and their overall 'carbon footprint'. Many Danish plants therefore have an integrated digester to convert sewage sludge into biogas, but the missing knowledge of the composition of the sludge is decreasing the efficiency of the production, according to Michael Beyer who is chemist at NanoNord and the project manager of the multi-NMR platform.

There is currently a big demand for optimizing the biogas production, not only in farm-based digesters, but especially in waste water treatment plants. Today you don't have many robust sensors at disposal to measure the conditions in and around the anaerobic digesters. The amount of dry matter content in the sewage sludge near the entrance to the digester is somewhat known, typically based on manual laboratory analysis or using often unreliable dry matter sensors.
Often it is known by experience when to add new sludge, and how much should be added, says Michael Beyer and continues:
There are many different microorganisms in the digester that create the microbiological community, and it's not all of them who potentially produce biogas. Some of them complicate the process with their metabolism, especially if the parameters aren't optimal. In general you can't really do much else than varying the feed-rate of the sludge, and see what happens. The options for optimizing the ongoing chemical processes are limited in today’s facilities.
The first step towards a more efficient biogas production is on-line measurements of the sewage sludge contents for relevant substances.
With Nanonord’s technology you can get precise information of the sludge’s methane producing potential, because the technology is able to measure the content of many NMR active isotopes in the sludge.
When you know what you add to the digester, you can classify and adjust your doses along with the process. Furthermore, knowledge of accumulation of inhibitors like ammonium inside the digester can help preventing process inhibition before it gets out of control.
All this makes a more efficient production possible, according to Michael Beyer.

One of the next natural steps is to integrate our NMR-sensor to on-line deliver separate measurements for nitrate, nitrite, ammonium and ‘inhibitors’ such as chlorine and metals for monitoring other waste water treatment processes like the Anammox process. Such process monitoring is today currently limited by missing availability of suitable on-line monitoring tools Michael continues.

Branch of known technology

The technology Tveskaeg, which NanoNord refers to as the product, has already been proven. Ole Jensen, CEO:
Nuclear magnetic resonance is about exposing the water to be measured with a high magnetic field, while simultaneously emitting and receiving radiowaves – The same as you will experience during a hospital MRI-scanning.
The substances –or NMR isotopes - we detect, in this case oxygen (dry matter content), nitrogen and phosphate and many more - each have their own NMR frequency, and with the right frequencies and advanced digital signal processing you can in many cases measure the exact amount of each such targeted isotopes in their relevant chemical bindings.

NanoNord already has experience with the NMR-technology. The company has in cooperation with iNano at Aarhus University, developed and with relevant industrial leaders in the ship-equipment field marketed the product CatGuard, which measures the amount of aluminium oxides in ship fuel. A monitoring process that can prevent engine failure and general degradation. NanoNord has also published articles on a mobile sensor to measure nitrogen, phosphor, and potassium in manure, to help farmers optimize manure handling.

Facts about Tveskaeg
Online NMR sensor for determination of dry matter content, nitrogen, phosphorous, silicon, sodium, aluminum, copper, lithium, chlorine, arsenic, beryllium, lead, mercury, cadmium, potassium and more in sewage sludge or any other water mixture.
The sensor is based on nuclear magnetic resonance measurements (NMR), requires no consumables and self-calibrating providing reliable systems with low total cost of ownership.
The sensor gives direct high precision quantitative measurements of NMR sensitive isotopes in the media. This enables for example increased efficiency of the biogas production process via better process control.

“You can measure nearly everything, as long as it can be pumped through our 9 mm borehole. Our NMR sensor technology has incredible many industrial uses in water and oil applications, which we are nowhere near finished investigating“, says managing director Ole Jensen

World News

No one before us has developed an NMR-sensor for sewage waste analysis, says Michael Beyer.
The available methods which often involve a destructive preparation of the sample you extract, typically by letting the sample react to chemicals, heating, vaporizing, fire, etc. It's time consuming, expensive and not environmentally appropriate. Alternative sensor types have the disadvantage that they have to be in direct contact with the sewage sludge or are dependent on optic windows, which have to stay clean.
Sensory equipment does not survive for very long in these environments without continual and expensive maintenance, says Ole Jensen and adds: Those are some challenges that you don't have with an NMR-sensor. Michael Beyer explains: The NMR-technology is virtually contact-free; the content which in this case would be sewage waste only gets in contact with a Teflon™ pipe. Therefore there would be no degradation. Skeptics talking about insufficient sensitivity of NMR-sensors are quickly dismissed at NanoNord:
Some have been dismissive and said we would never be able to get it working, because the technology isn't as sensitive as other sensor types. But we have the advantage, that we can often measure the same sample over a long period of time – multiple hours – without spoiling the sample. With that we can achieve the same sensitivity, and it's still way more efficient than having to extract a sample, then ship it off for analysis and waiting for the result, says Michael Beyer. Less maintenance means that the overall cost of an NMR-based measuring system is lower than other technological solutions.

Platform with great potential

The dream scenario, according to the CEO of NanoNord, is to create a flexible and open platform, that others can create software NMR algorithms for, with the goal of measuring a vast amount of substances of different matters. This is the goal of the Tveskaeg platform.
This one platform could replace a myriad of other type of sensors; you can measure unbelievably many things, which today requires specific sensors. It could revolutionize the water industry. Our current mission is to demonstrate that the technology works in this area, and simultaneously confirming that it's in no way limited to measuring these exact substances in waste, or in the water sector for that matter, says Ole Jensen. His enthusiasm about the potential of NMR-technology is tangible; the opening dialog with potential partners has increased his faith that Tveskaeg will be a huge success.
We're talking with the important players on the market, Danish as well as foreign. They all say it's a huge leap forward what we're doing, says Ole Jensen who has had many years of experience as an entrepreneur and is used to dealing with international organizations.
The interest is huge, and everything suggests we're holding an extremely attractive technology and products to go with it.
Besides developing Tveskaeg, the time is being used on establishing relevant cooperators and finding the right commercial partner. The technology is ready for shipment in products before the end of the year 2015. - And more than that, I'd think we're ready for the market with the universal platform version of the technology in 2016, says Ole Jensen.