Aqueous particle generation with a 3D printed nebulizer

• Main Authors: M. Rösch, D. J. Cziczo
• Format: Article
• Language: English
• Published: Copernicus Publications 2020-12-01
• Series: Atmospheric Measurement Techniques
• Online Access: https://amt.copernicus.org/articles/13/6807/2020/amt-13-6807-2020.pdf

<p>In this study, we describe the design and testing of a high-output-stability, constant-liquid-feed nebulizer using the Venturi principle to generate liquid particles from solutions. This atomizer, the PRinted drOpleT Generator (PROTeGE), was manufactured using stereolithography (SLA) printing. Different concentrations of ammonium sulfate solutions were used to characterize the size and number concentration of the generated particles. A comparison of a 3D printed 0.5 mm orifice against a commercially available 0.5 mm brass orifice using the same ammonium sulfate solution was also performed. The particle number concentration generated with the printed orifice was higher, by <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>∼</mo><mo>×</mo><mn mathvariant="normal">2</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="26pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="43ac3ff1ae1688277be9dbf9f129701b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-13-6807-2020-ie00001.svg" width="26pt" height="10pt" src="amt-13-6807-2020-ie00001.png"/></svg:svg></span></span>, than the particle number concentration generated with the brass orifice.</p> <p>PROTeGE is also capable of dispersing polystyrene latex (PSL) spheres for calibration purposes. The particle number concentrations obtained in this study ranged from <span class="inline-formula">∼</span> 10 000 cm<span class="inline-formula">⁻³</span> for 0.75 <span class="inline-formula">µ</span>m to <span class="inline-formula">∼</span> 100 cm<span class="inline-formula">⁻³</span> for 5.0 <span class="inline-formula">µ</span>m PSL particles with a dependence on the concentration of the dispersed solution. For the different concentrated ammonium sulfate solutions particle number concentrations from <span class="inline-formula">∼</span> 14 000 cm<span class="inline-formula">⁻³</span> for 0.1 g L<span class="inline-formula">⁻¹</span> to 7600 cm<span class="inline-formula">⁻³</span> for 5.0 g L<span class="inline-formula">⁻¹</span> were measured. An additional measurement with a scanning electrical mobility system (SEMS) was performed for the 0.6 g L<span class="inline-formula">⁻¹</span> solution to measure particles in the size range of 10 to 1000 nm. The generated particle number size distributions (PNSDs) showed a maximum at 50 nm with particle number concentrations of <span class="inline-formula">∼</span> 40 000 cm<span class="inline-formula">⁻³</span>. PROTeGE is easy to manufacture and operate, low in maintenance, and cost-effective for laboratory and field generation of particles from aqueous media in a size range of 10 to 5000 nm.</p>