Cases Overview

KNF Air Sampling Pumps Help Track Desert Dust

Specially customized KNF diaphragm pumps enable precise tracing of particulate matter air pollution from Sahara Desert

KNF air sampling pumps help tracking non-human particulate matter air pollution.

Orange skies, hazy sunshine, cars covered in dust: the reddish rain that descended on Southern and Central Europe in mid-March of 2022 was an unusually high concentration of Sahara dust. The Meteorological Observatory in Bavaria described it as an extraordinarily strong but very infrequent event. To gain a better understanding on the global effects of this phenomenon, the Detection of Non-Anthropogenic Air Pollution project (DNAAP) traces this particulate matter air pollution with the help of KNF air sampling pumps.

Global Phenomenon Fueled by Storms

Whirled up by storms in the Sahara, desert dust travels around the entire globe. When cyclones appear in the Mediterranean Sea, they can cause the particulate matter air pollution to become very strong. As a result, a yellow-red layer of dust can be seen with the naked eye in distant regions on windows and vehicles.

Inconspicuous Dust With a Tremendous Impact

These mineral particles have an average size of just a few micrometers. They can serve as fertilizer in nutrient-low regions, influence the Earth’s temperature by blocking out the sun and trigger cloud formation processes by providing condensation nuclei. The particles are also considered fine particulate matter air pollution with a negative impact on human health.

Tracking Dust in Real Time in the Mediterranean

The research project DNAAP collects data on particulate matter air pollution caused by natural phenomena in real time. Dust particles are measured using light absorption at locations in Cyprus, Spain and Slovenia. This provides information about the concentration of mineral dust, especially Sahara Desert dust, in the Mediterranean region. KNF air sampling pumps play a crucial role in the project.

Excluding Black Carbon From the Sample

DNAAP’s leading project partner, Aerosol d.o.o., uses the Magee Scientific Aethalometer Model AE33 for real-time measurement. To measure only non-anthropogenic particulate matter air pollution, it is necessary to filter out black carbon. This type of carbon is mostly the result of human activities such as slash-and-burn fires and the burning of fossil fuels. For this reason, a virtual impactor is connected upstream in order to separate the unwanted black carbon from the desert dust particles before they enter the analysis unit.

Sometimes, dust storms become so strong in the Sahara Desert that a yellow-red layer of dust can be seen on windows and vehicles in distant areas.
Sometimes, dust storms become so strong in the Sahara Desert that a yellow-red layer of dust can be seen on windows and vehicles in distant areas.

Air Sampling Pump Helps Purifying Dust

A customized KNF N 940 air sampling pump delivers the intake air to the virtual impactor. There, the air is divided into a main flow of 98 l/min and a minor flow of 2 l/min. Saharan dust is coarse, so the particles are inertially impacted into the minor flow. With the black carbon excluded, the minor flow containing the dust is then fed to the absorption photometer for analysis.

Second KNF Pump Helps Detecting Dust

In the Aethalometer, a KNF N 86 diaphragm gas pump delivers the minor flow at a defined volume to the device’s analysis chamber. There, the air is drawn through a filter tape. The tape is simultaneously illuminated by light while detectors measure the intensity of light transmitted through the tape. As desert dust accumulates, the intensity of light transmitted through the tape gradually decreases indicating the presence of particulate matter air pollution.

Customized Air Sampling Pumps

KNF plays a role in this project by providing pumps for the impactor as well as for the Aethalometer. Both pumps have been customized for their specific tasks and in accordance with the requirements of the operational environments. The KNF N 86 pump used as an air sampling pump in the Aethalometer was tailored to make installation quick and easy. This was achieved with the help of specially adapted plugs and sockets.

Maximum Reliability Through Customization

The customized air sampling pump in the impactor is based on a KNF N 940. It is specially equipped with parallel connected pump heads for a higher flow rate of 100 l/min and its aluminum pump heads have been anodized. This makes the pump head resistant to the humid environment of the measuring points, resulting in maximum durability.

Application With Demanding Conditions

The reliability and maintenance-free operations of the air sampling pumps are important for this application due to the coastal ambient conditions of the measuring points and their often-remote locations. The pump also uses a brushless DC electric motor. This motor type runs wear-free and is very robust, increasing the pump’s reliability even further.

Live Data Openly Available

KNF is proud to be a part of this project which helps humankind to trace particulate matter air pollution and to gain further insights into the functioning of our global climate. The data of the research project is open to the public and can be accessed online in real-time. On a map, the trajectory of various pollutants can also be seen.