The authors acknowledge the support of the LUT RESOURCE (Resource efficient production processes and value chains) research platform coordinated by LUT University and the by the Life IP on waste&#8212;Towards a circular economy in Finland (LIFE-IP CIRCWASTE-FINLAND) project (LIFE 15 IPE FI 004). Funding for the project was received from the EU Life Integrated program, companies, and cities.

1. Identification and pre-treatment
<ol>
	<li>Identify polymers in plastic with the portable near-infrared (NIR) spectroscopy tool in the spectral range of 1600&#8211;2400 nm. Contact the polymer with spectroscopy tool and determine the polymer by the measured reflectance.
	<ol>
		<li>According to the identification curve of spectroscopy, analyze the identification results from the screen in the laboratory.</li>
	</ol>
	</li>
	<li>Based on the identification result, sort materials between the polymers and measure their respective weights. 
	NOTE: The material was sorted and weighted according to the measured identification results. Selected polymers for further processing were ABS, PE, and PP with the amounts, 27.1, 14.2, and 44.7 kg, respectively.</li>
	<li>Perform size reduction for the selected plastic materials in laboratory conditions with a crusher apparatus. Place collected and identified materials into the apparatus that crushed materials with the mechanical force of hammer impacts.
	<ol>
		<li>Crush plastic materials using a single-shaft shredding system with a crusher/shredder apparatus equipped with a sieve size varying from 10 to 20 mm.</li>
		<li>Subject the plastic fragments to a low-speed crusher, equipped with a 5 mm sieve. Ensure that the material is homogenous.</li>
	</ol>
	</li>
	<li>Measure the material amounts for composites. Show a recipe as an example and present these materials in the relative amounts of plastic, wood, coupling agent, and lubricant (64, 30, 3, and 3 wt%, respectively). 
	NOTE: Three different composites were studied in this study. The recycled plastic polymers from the CDW were ABS, PP, and PE. The filler of the composite material was wood flour, which was prepared from a dried spruce species (Picea abies) size reduced using crushing equipment and sieved for a homogeneous size (20 mm mesh). Commercial additives of coupling agent and lubricant were used. The compositions and name of the prepared materials are shown in Table 1.</li>
</ol>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Material</td>
			<td>Polymer 
			/ amount</td>
			<td>Wood</td>
			<td>CA</td>
			<td>Lubr</td>
		</tr>
		<tr>
			<td>CDW-ABS</td>
			<td>ABS / 30</td>
			<td>64</td>
			<td>3</td>
			<td>3</td>
		</tr>
		<tr>
			<td>CDW-PP</td>
			<td>PP / 30</td>
			<td>64</td>
			<td>3</td>
			<td>3</td>
		</tr>
		<tr>
			<td>CDW-PE</td>
			<td>PE / 30</td>
			<td>64</td>
			<td>3</td>
			<td>3</td>
		</tr>
	</tbody>
</table>
Table 1: The composition of the studied materials. The name of the sample consists of the included matrix component, recycled acrylonitrile butadiene styrene (ABS), polypropylene (PP), and polyethylene (PE) from the construction and demolition waste (CDW). The amounts of wood, coupling agent (CA) and lubricant (Lubr.) were the same in all samples.
2. Processing of WPC materials with extrusion technology after size reduction treatment
<ol>
	<li>Transfer the identified and pre-treated materials into closer the next (agglomeration) processing step. 
	CAUTION: The plastic material of ABS includes a styrene component. The International Agency for Research on Cancer considers that styrene is &#8220;possibly carcinogenic to humans&#8221;. Therefore, the agglomeration step in action was not included in the filming but its process is outlined in this work. Additionally, only PP or PE polymer was used in the extrusion production during filming.</li>
	<li>Perform agglomeration of the material.
	<ol>
		<li>Mix all components of the process (polymer, wood, coupling agent, and lubricant) in an apparatus that consists of a turbomixer and a cooler. Agglomerate the materials in the turbomixer until the temperature of the materials reached 200 &#176;C. Due to the combined effect of temperature and friction, the granules materials were formed after the treatment process of agglomeration.</li>
		<li>Cool the materials after turbomixer treatment for 4-7 minutes in a cooler apparatus.</li>
	</ol>
	</li>
	<li>Evacuate material from the process and collect up agglomerated material.</li>
	<li>Transfer the agglomeration&#8211;treated materials to the next process step (extrusion).
	<ol>
		<li>Click the control panel of the extrusion machine and check for the correct parameters. The average barrel and tool temperatures varied between 167 and 181 &#176;C, and 183 and 207 &#176;C, respectively. The melt temperature varied between 164 and 177 &#176;C, and the die pressures were between 3.7 and 5.9 MPa. Adjust parameters because recycled materials are heterogeneous, and the process requires professional control.</li>
		<li>Compound the components using a conical counter-rotating twin-screw extruder with 15 kg/h material output. The parameters of the materials are presented in Table 2. After the extrusion process, the profile material of the composite was generated.</li>
	</ol>
	</li>
</ol>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Material</td>
			<td>Barrel T &#176;C</td>
			<td>Tool T &#176;C</td>
			<td>Melt T &#176;C</td>
			<td>Melt 
			Pressure (bar)</td>
			<td>Feeding 
			rate (kg/h)</td>
			<td>Avg.Screw 
			speed (rpm)</td>
		</tr>
		<tr>
			<td>CDW-ABS</td>
			<td>181 &#177; 11.9</td>
			<td>189 &#177; 14.7</td>
			<td>177</td>
			<td>50</td>
			<td>15</td>
			<td>14</td>
		</tr>
		<tr>
			<td>CDW-PP</td>
			<td>170 &#177; 10.4</td>
			<td>207 &#177; 8.62</td>
			<td>164</td>
			<td>37</td>
			<td>15</td>
			<td>15</td>
		</tr>
		<tr>
			<td>CDW-PE</td>
			<td>167 &#177; 8.51</td>
			<td>183 &#177; 10.1</td>
			<td>164</td>
			<td>59</td>
			<td>15</td>
			<td>13</td>
		</tr>
	</tbody>
</table>
Table 2: Processing parameters of the composite materials. (Values after the &#8216;&#177;&#8217;-mark indicate standard deviations. Avg. = average)
3. Sampling of produced materials and analyzes of properties
<ol>
	<li>Prepare samples for mechanical property tests in the laboratory.
	<ol>
		<li>Cut samples from extruded profiles with a machine (i.e., a sliding table saw). Three different size specimens are needed for tests: flexural, tensile, and impact strength.</li>
		<li>Determine the size of test samples according to the applicable standards, based on the recommendation of EN 1553416. According to the standard, test a minimum of five specimens but the number of measurements may be more than five if greater precision of the mean value is required.</li>
	</ol>
	</li>
	<li>Saw test samples from the extruded materials for the flexural property test, according to the standard EN 31017.
	<ol>
		<li>Use a sliding table saw with the following dimensions for the sample: 800 mm x 50 mm x 20 mm (length, width, thickness).</li>
		<li>Manufacture 20 samples for the analysis of flexural properties (strength and modulus).</li>
	</ol>
	</li>
	<li>Saw test samples from the extruded materials for the tensile property test, according to the standard EN ISO 527 218. Use the sliding table saw to cut the material into the following dimensions: 150 mm x 20 mm x 4 mm (length, width, thickness).
	<ol>
		<li>Set the material preforms for machining of a dumb-bell shape via computer numerical control (CNC). The width of the sample at its narrow portion was 10 mm, and the cross-sectional surface area of the sample was 4 mm x 10 mm, where the tensile stress was addressed. The length of the narrow portion was 60 mm, ending in a rounded corner with a radius of 60 mm.</li>
		<li>Make 20 samples for the analysis of tensile properties (strength and modulus).</li>
	</ol>
	</li>
	<li>Saw test samples from the extruded materials for the impact strength test, according to the standard EN ISO 179-119.
	<ol>
		<li>Use the sliding table saw to cut the samples into the following dimensions: 80 mm x 10 mm x 4 mm (length, width, thickness). Make 20 samples for the analysis of impact strength property.</li>
	</ol>
	</li>
	<li>Move the test material into the 23 &#176;C and 50% relative humidity condition chamber, according to standard EN ISO 29120, until a constant mass is reached. Ensure that samples are conditioned before the testing of material properties.</li>
	<li>Perform the tests (flexural, tensile, and impact). Determine the mechanical features of specimens by flexural and tensile strength tests with a testing machine in accordance with the EN 31017 and EN ISO 527-218 standards, respectively.
	<ol>
		<li>Perform flexural strength and modulus test for each of 20 samples, using the testing apparatus. Set flexural test sample at the support of two points and apply a load to the center of sample by clicking Test start in the computer program that controls the testing apparatus, with a pre-load of 15 N and test speed of 10 mm/min. The test stops automatically after recording the result. Remove test sample from the support tools and set a new sample on the tools.
		<ol>
			<li>Repeat procedure until 20 samples were tested and results from the program were registered. The computer program calculates average results from the test. 
			NOTE: The protocol can be paused here while test tools will be changed for the testing apparatus.</li>
		</ol>
		</li>
		<li>Perform tensile strength and modulus test for 20 machined (dumb-bell-shaped) samples. Set the tensile test sample between the test tools and attach pneumatic clamps, which will keep the sample in the tools during the test. Start the test from the computer control panel, with a pre-load of 10 N and test speed of 2 mm/min, and attach an extension meter tool immediately after the test start. 
		NOTE: The extension meter tool measures the tensile modulus from the sample. Each test stopped automatically after its result was recorded.
		<ol>
			<li>Remove the test sample from the tool after each test and set a new sample on the tools. Repeat procedure for all samples. The computer program calculates average result values.</li>
		</ol>
		</li>
		<li>Perform an impact strength test with an impact tester, according to standard EN ISO 179-119. Set the 10 mm x 4 mm size of (width, thickness) sample between the support, reset the force and release the impact hammer of 5 kpcm. 
		NOTE: The impact strength test sample ruptures due to the impact of hammer and the amount of absorbed energy is visible in the tester indicator.
		<ol>
			<li>Record the result and repeat the for the 20 samples, after which the average value of impact strength is calculated. The recorded results were in &#8220;kpcm&#8221; unit, which was changed into joule (J), and the results were presented as a kilojoule per square meter. 
			NOTE: The span between sample support (distance between the lines of the contact the of sample) in the impact strength test was 62 mm or, alternatively, 20x its thickness.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Analyze the results from the mechanical tests, which are presented in Figure 1, Figure 2 and Figure 3.</li>
</ol>

<ol>
	<li>The World Bank. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+a+Waste+2.0:+A+Global+Snapshot+of+Solid+Waste+Management+to+2050.">What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050.</a> International Bank for Reconstruction and Development/The World Bank. , (2018).</li><li>Llatas, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+model+for+quantifying+construction+waste+in+projects+according+to+the+European+waste+list.">A model for quantifying construction waste in projects according to the European waste list.</a> Waste Management. 31, 1261-1276 (2011).</li><li>Waste streams, Construction and Demolition Waste (CDW). European Commission (EC) Available from: <a target="_blank" href="https://ec.europa.eu/environment/waste/construction_demolition.htm">https://ec.europa.eu/environment/waste/construction_demolition.htm</a> (2019)</li><li>Plastics - the Facts 2018. PlasticsEurope Available from: <a target="_blank" href="https://www.plasticseurope.org/application/files/6315/4510/9658/Plastics_the_facts_2018_AF_web.pdf">https://www.plasticseurope.org/application/files/6315/4510/9658/Plastics_the_facts_2018_AF_web.pdf</a> (2018)</li><li>European Commission (EC). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Communication+from+the+Commission+to+the+European+Parliament,+the+Council+the+European+Economic+and+Social+Committee+and+the+committee+and+the+Committee+of+the+Regions,+COM.">Communication from the Commission to the European Parliament, the Council the European Economic and Social Committee and the committee and the Committee of the Regions, COM.</a> European Commission (EC). , (2015).</li><li>Directive 2008/98/EC. European Union (EU) Available from: <a target="_blank" href="https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32008L0098&amp;from=EN">https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32008L0098&amp;from=EN</a> (2008)</li><li>Anugwom, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lignin+as+a+functional+additive+in+a+biocomposite:+Influence+on+mechanical+properties+of+polylactic+acid+composites.">Lignin as a functional additive in a biocomposite: Influence on mechanical properties of polylactic acid composites.</a> Industrial Crops &amp; Products. 140, 111704 (2019).</li><li>Sommerhuber, P. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Life+cycle+assessment+of+wood-plastic+composites:+Analysing+alternative+materials+and+identifying+an+environmental+sound+end-of-life+option.">Life cycle assessment of wood-plastic composites: Analysing alternative materials and identifying an environmental sound end-of-life option.</a> Resources, Conservation and Recycling. 117, 235-248 (2017).</li><li>Hyv&#228;rinen, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+the+use+of+construction+and+demolition+waste+on+the+mechanical+and+moisture+properties+of+a+wood-plastic+composite.">The effect of the use of construction and demolition waste on the mechanical and moisture properties of a wood-plastic composite.</a> Composites Structures. 210, 321-326 (2019).</li><li>Liikanen, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Construction+and+demolition+waste+as+a+raw+material+for+wood+polymer+composites+-+Assessment+of+environmental+impacts.">Construction and demolition waste as a raw material for wood polymer composites - Assessment of environmental impacts.</a> Journal of Cleaner Production. 225, 716-727 (2019).</li><li>V&#228;ntsi, O., K&#228;rki, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+assessment+of+recycled+mineral+wool+and+polypropylene+utilized+in+wood+polymer+composites.">Environmental assessment of recycled mineral wool and polypropylene utilized in wood polymer composites.</a> Resources, Conservation and Recycling. 104, 38-48 (2015).</li><li>Geyer, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production,+use+and+fate+of+all+plastics+ever+made.">Production, use and fate of all plastics ever made.</a> Science Advances. 3, 1-5 (2017).</li><li>Global Plastic Recycling Market: Snapshot. Transparency Market Research Available from: <a target="_blank" href="https://www.transparencymarketresearch.com/plastic-recycling-market.html">https://www.transparencymarketresearch.com/plastic-recycling-market.html</a> (2018)</li><li>Turku, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Durability+of+wood+plastic+composites+manufactured+from+recycled+plastic.">Durability of wood plastic composites manufactured from recycled plastic.</a> Heliyon. 4, (2018).</li><li>Turku, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+wood+plastic+composites+manufactured+from+recycled+plastic+blends.">Characterization of wood plastic composites manufactured from recycled plastic blends.</a> Composite Structures. 161, 469-476 (2017).</li><li>National Standards Authority of Ireland. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CEN+-+EN+15534-1:2014+++A1:2017,+Composites+made+from+cellulose-based+materials+and+thermoplastics+(usually+called+wood-polymer+composites+(WPC)+or+natural+fibre+composites+(NFC))+-+Part+1:+Test+methods+for+characterisation+of+compounds+and+products.">CEN - EN 15534-1:2014 + A1:2017, Composites made from cellulose-based materials and thermoplastics (usually called wood-polymer composites (WPC) or natural fibre composites (NFC)) - Part 1: Test methods for characterisation of compounds and products.</a> National Standards Authority of Ireland. , (2014).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EN+310:1993,+Wood-based+panels+-+Determination+of+modulus+of+elasticity+in+bending+and+of+bending+strength.">EN 310:1993, Wood-based panels - Determination of modulus of elasticity in bending and of bending strength.</a> International Organization for Standardization. , (1993).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EN+ISO+527+2,+Plastics+-+Determination+of+tensile+properties+-+Part+2:+Test+conditions+for+moulding+and+extrusion+plastics.">EN ISO 527 2, Plastics - Determination of tensile properties - Part 2: Test conditions for moulding and extrusion plastics.</a> International Organization for Standardization. , (2012).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EN+ISO+179-1,+Plastics+-+Determination+of+Charpy+impact+properties+-+Part+1:+Non-instrumented+impact+test.">EN ISO 179-1, Plastics - Determination of Charpy impact properties - Part 1: Non-instrumented impact test.</a> International Organization for Standardization. , (2010).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EN+ISO+291,+Plastics+-+Standard+atmospheres+for+conditioning+and+testing.">EN ISO 291, Plastics - Standard atmospheres for conditioning and testing.</a> International Organization for Standardization. , (2008).</li><li>Klyosov, A. A., Klyosov, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composition+of+Wood-Plastic+Composite+Deck+Boards:+Thermoplastic.">Composition of Wood-Plastic Composite Deck Boards: Thermoplastic.</a> Wood-plastic composites. , 50-74 (2007).</li><li>Martikka, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improving+durability+of+wood-mixed+waste+plastic+composites+with+compatibilizers.">Improving durability of wood-mixed waste plastic composites with compatibilizers.</a> IOP Conference Series: Materials Science and Engineering. 490, 1-9 (2019).</li><li>Martikka, O., K&#228;rki, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Promoting+recycling+of+mixed+waste+polymers+in+wood-polymer+composites+using+compatibilizers.">Promoting recycling of mixed waste polymers in wood-polymer composites using compatibilizers.</a> Recycling. 4, (2019).</li><li>Keener, T. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maleated+coupling+agents+for+natural+fibre+composites.">Maleated coupling agents for natural fibre composites.</a> Composites: Part A. 35, 357-362 (2004).</li><li>Sain, M., Pervaiz, M., Oksman Niska, K., Sain, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+properties+of+wood-polymer+composites.">Mechanical properties of wood-polymer composites.</a> Wood-polymer composites. , 101-117 (2008).</li><li>Rocha, D. B., Rosa, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupling+effect+of+starch+coated+fibers+for+recycled+polymer/wood+composites.">Coupling effect of starch coated fibers for recycled polymer/wood composites.</a> Composites: Part B. 172, 1-8 (2019).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EN+ISO+178:2010,+Plastics+-+Determination+of+flexural+properties.">EN ISO 178:2010, Plastics - Determination of flexural properties.</a> International Organization for Standardization. , (2010).</li><li>Klyosov, A. A., Klyosov, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flexural+Strength+(MOR)+and+Flexural+Modulus+(MOE)+of+Composite+Materials+and+Profiles.">Flexural Strength (MOR) and Flexural Modulus (MOE) of Composite Materials and Profiles.</a> Wood-plastic composites. , 225-318 (2007).</li></ol>

Circwaste-project receives financial support from EU for the production of its material. The views reflected within the content are entirely the project&#8217;s own and the EU commission is not responsible for any use of them.

The mechanical properties of WPC play an important role in deciding the suitability of these products in various applications. WPC consists of three main ingredients: plastic, wood, and additives. The mechanical properties of fiber-based composites depend on the length of the used fiber, where &#8220;critical fiber length&#8221; is the term used to indicate sufficient reinforcement25. In addition to the properties of ingredients, the quality of raw materials is the important factor for the perform...

Global waste generation has grown significantly throughout history and is predicted to increase by tens of percentages in the future unless action is taken1. In particular, high-income countries have generated more than one-third of the world&#8217;s waste although they account for only 16% of the global population1. The construction sector is a significant producer of this waste due to rapid urbanization and population growth. According to estimates, approximately one-third of global solid waste is formed by construction and demolition projects; however, exact values from different areas are missing2. In the European Union (EU), the amount of construction and demolition waste (CDW) is approximately 25%&#8211;30% of total waste generation3, and includes valuable and significant secondary raw materials, like plastic. Without organized collection and management, plastic may contaminate and adversely influence ecosystems. In 2016, 242 million tons of plastic waste were generated in the world1. The share of plastic recycled in Europe was only 31.1%4.
Resource scarcity has created a need to change practices toward a circular economy, in which the aims are to use waste as a source of secondary resources and recover waste for reuse. Economic growth and minimized environmental impacts will be created by the circular economy, which is a popular concept in Europe. The European Commission adopted a European Union Action Plan for a circular economy, which set goals and indicators for contributions5.
Tighter environmental regulations and laws are contributing to the construction sector putting more effort into waste management and material recycling issues. For example, the European Union (EU) has set targets for material recovery. From the year 2020 onwards, the material recovery rate of non-hazardous CDW should be 70%6. The composition of CDW may vary widely across geographical locations but some common characteristics can be identified, including, for example, plastic that is a potential and valuable raw material for wood-polymer composites. The reutilization of plastic is a concrete step towards a circular economy in which virgin plastic polymers are substituted by recycled polymer.
Composite materials are a multi-phase system, consisting of a matrix material and reinforcing phase. Wood-polymer composite (WPC) typically contains polymers as the matrix, wood materials as reinforcement, and additives for improving adhesion, such as coupling agents and lubricants. WPC can be known as an environmentally friendly material because the raw material can be sourced from renewable materials, such as polylactic acid (PLA) and wood. According to the latest innovation7, the additives of WPC can be based on renewable sources. Additionally, the source of the raw material can be recycled (non-virgin) materials, which is an ecologically and technically superior alternative8. For example, researchers have studied extruded WPC that contains CDW, and found that the properties of CDW&#8211;based composites were at an acceptable level9. Utilization of recycled raw materials as a component for WPC is also acceptable from the environmental aspect, as proved by several assessments. Overall, it has been demonstrated that utilizing CDW in WPC production can decrease the environmental influences of CDW management10. In addition, it has been found that using recycled polypropylene (PP) plastic in WPC has the potential to reduce global warming11.
The amount of available recycled polymers will increase in the future. Global plastic production has increased approximately 9% as per year, on average, and it is expected that this increment will continue in the future12. The most general plastic polymer types are, inter alia, polypropylene (PP) and polyethylene (PE). The shares of total demand for PE and PP were 29.8% and 19.3%, respectively, in Europe in 20174. The global plastic recycling market is expected to grow at an annual growth rate of 5.6% during the period 2018&#8211;202613. One of the main applications in which plastics is used is building and construction. For example, almost 20% of the total demand for European plastic was associated with building and construction applications4. From an economic perspective, the use of recycled polymers in WPC manufacturing is an interesting alternative, leading to the production of materials with low cost. Previous research has shown that physical effects have a stronger influence on extruded materials made from secondary plastic compared to the corresponding virgin material, but properties depend on the plastic source14. However, the use of recycled plastic decreases the strength of WPC due to lower compatibility15. Variation between the structures of plastic polymers causes concerns for re-use and recycling, which contribute to the importance of plastic sorting based on the polymer.
This study intends to assess the utilization of plastic material from CDW as a raw material for WPC. The polymer fractions assessed in the study are acrylonitrile butadiene styrene (ABS), polypropylene (PP), and polyethylene (PE). These are known as universal plastic fractions within CDW. The polymer fractions are treated with general manufacturing processes, such as agglomeration and extrusion, and are tested with universal mechanical property tests. The primary objective of the study is to discover how the properties of WPC would alter if recycled polymers were used as a raw material in matrix instead of primary virgin polymers.
Based on the (local) waste management center (Etel&#228;-Karjalan J&#228;tehuolto Oy), it was shown how plastic-rich CDW is stored. It was demonstrated that a great amount plastic material is included and some examples of CDW plastic polymers were shown. Researchers collected the most suitable polymers for further processing, such as ABS, PP, and PE. The desired polymers (PE, PP, ABS) were identified using portable near infrared (NIR) spectroscopy. WPC product examples were presented in which where collected plastic materials could be utilized as a raw material. The definition of the composite and its advantages were explained.

<table>
	<tbody>
		<tr>
			<td>Agglomeration</td>
			<td>Plasmec</td>
			<td>TRL100/FV/W</td>
			<td>apparatus of turbomixer</td>
		</tr>
		<tr>
			<td>Agglomeration</td>
			<td>Plasmec</td>
			<td>RFV 200</td>
			<td>apparatus of cooler</td>
		</tr>
		<tr>
			<td>CNC router</td>
			<td>Recontech</td>
			<td>F2 - 1325 C</td>
			<td>CNC machine</td>
		</tr>
		<tr>
			<td>Condition chamber</td>
			<td>Memmert</td>
			<td>HPP260</td>
			<td>constant climate chamber</td>
		</tr>
		<tr>
			<td>Coupling agent</td>
			<td>DuPont</td>
			<td>Fusabond E226</td>
			<td>commercial coupling agent additive</td>
		</tr>
		<tr>
			<td>Crusher 1 (crusher/shredder )</td>
			<td>Untha</td>
			<td>Untha LR 630</td>
			<td>10-20 mm sieve</td>
		</tr>
		<tr>
			<td>Crusher 2 (low-speed crusher)</td>
			<td>Shini</td>
			<td>Shini SG-1635N-CE</td>
			<td>5 mm sieve, granulator</td>
		</tr>
		<tr>
			<td>Extruder</td>
			<td>Weber</td>
			<td>Weber CE 7.2</td>
			<td>conical counter-rotating twin-screw</td>
		</tr>
		<tr>
			<td>Lubricant</td>
			<td>Struktol</td>
			<td>TPW 113</td>
			<td>commercial lubricant additive</td>
		</tr>
		<tr>
			<td>NIR spectroscopy</td>
			<td>Thermo Fisher Scientific</td>
			<td>Thermo Scientific microPHAZIR PC</td>
			<td></td>
		</tr>
		<tr>
			<td>Recycled material ABS from CDW</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Recycled material PE from CDW</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Recycled material PP from CDW</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sliding table saw</td>
			<td>Altendorf</td>
			<td>F-90</td>
			<td>circular saw/sliding table saw</td>
		</tr>
		<tr>
			<td>Testing apparatus</td>
			<td>Zwick</td>
			<td>5102</td>
			<td>impact tester</td>
		</tr>
		<tr>
			<td>Testing machine</td>
			<td>Zwick Roell</td>
			<td>Z020</td>
			<td>allround-line materials testing machine</td>
		</tr>
		<tr>
			<td>Wood flour (Spruce) material</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>WPC example material</td>
			<td>UPM Profi</td>
			<td></td>
			<td>Decking board</td>
		</tr>
	</tbody>
</table>

the effect of construction and demolition waste plastic fractions on wood-polymer composite properties

Construction and demolition waste (CDW), including valuable materials such as plastics, have a remarkable influence on the waste sector. In order for plastic materials to be re-utilized, they must be identified and separated according to their polymer composition. In this study, the identification of these materials was performed using near-infrared spectroscopy (NIR), which identified material based on their physical-chemical properties. Advantages of the NIR method are a low environmental impact and rapid measurement (within a few seconds) in the spectral range of 1600-2400 nm without special sample preparation. Limitations include its inability to analyze dark materials. The identified polymers were utilized as a component for wood-polymer composite (WPC) that consists of a polymer matrix, low cost fillers, and additives. The components were first compounded with an agglomeration apparatus, followed by production by extrusion. In the agglomeration process, the aim was to compound all materials to produce uniformly distributed and granulated materials as pellets. During the agglomeration process, the polymer (matrix) was melted and fillers and other additives were then mixed into the melted polymer, being ready for the extrusion process. In the extrusion method, heat and shear forces were applied to a material within the barrel of a conical counter-rotating twin-screw type extruder, which reduces the risk of burning the materials and lower shear mixing. The heated and sheared mixture was then conveyed through a die to give the product the desired shape. The above-described protocol proved the potential for re-utilization of CDW materials. Functional properties must be verified according to the standardized tests, such as flexural, tensile, and impact strength tests for the material.

To investigate the effect of CDW plastic polymer on the mechanical properties of WPC, three different polymer types as a matrix were studied. Table 1 presents the composition of materials and Table 2 reports the manufacturing processes. The material of CDW-PP requires a higher treatment temperature for tools but, correspondingly, melt pressure was lower compared to the other materials (CDW-ABS and CDW-PE).
Figure 1 presents the fl...

Watch this Scientific Journal Video about The Effect of Construction and Demolition Waste Plastic Fractions on Wood-Polymer Composite Properties at JoVE.com

The Effect of Construction and Demolition Waste Plastic Fractions on Wood-Polymer Composite Properties

Secondary material streams have been shown to include potential raw materials for production. Presented here is a protocol in which CDW-plastic waste as a raw material is identified, followed by various processing steps (agglomeration, extrusion). As a result, a composite material was produced, and mechanical properties were analyzed.

Construction and demolition waste (CDW), including valuable materials such as plastics, have a remarkable influence on the waste sector. In order for ...

the-effect-construction-demolition-waste-plastic-fractions-on-wood

Research

Education

JoVE Core

JoVE Journal

Civil Engineering

Environment

Unit 1

Wood

SCIENTISTS IN ACTION

6.8K Views.  LUT University. Secondary material streams have been shown to include potential raw materials for production. Presented here is a protocol in which CDW-plastic waste as a raw material is identified, followed by various processing steps (agglomeration, extrusion). As a result, a composite material was produced, and mechanical properties were analyzed.

Video: The Effect of Construction and Demolition Waste Plastic Fractions on Wood-Polymer Composite Properties

Waste Water Derived Electroactive Microbial Biofilms: Growth, Maintenance, and Basic Characterization

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup controlled by a potentiostat. Thereby the use of potentiostats allows an exact adjustment of the electrode potential and ensures reproducible microbial culturing conditions. During growth the current production is monitored using chronoamperometry (CA). Based on these data the maximum current density (jmax) and the coulombic efficiency (CE) are discussed as measures for characterization of the bioelectrocatalytic performance. Cyclic voltammetry (CV), a nondestructive, i.e. noninvasive, method, is used to study the extracellular electron transfer (EET) of electroactive bacteria. CV measurements are performed on anodic biofilm electrodes in the presence of the microbial substrate, i.e. turnover conditions, and in the absence of the substrate, i.e. nonturnover conditions, using different scan rates. Subsequently, data analysis is exemplified and fundamental thermodynamic parameters of the microbial EET are derived and explained: peak potential (Ep), peak current density (jp), formal potential (Ef) and peak separation (&#916;Ep). Additionally the limits of the method and the state-of the art data analysis are addressed. Thereby this video-article shall provide a guide for the basic experimental steps and the fundamental data analysis.

Chronoamperometric growth of anodic electroactive microbial biofilms in a fed-batch reactor using a three-electrode setup, controlled by a potentiostat, is demonstrated. The extracellular electron transfer is characterized using cyclic voltammetry in the presence of the electron donor and in the absence of the electron donor. Fundamental data analysis is demonstrated.

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup ...

Methods for Facilitating Microbial Growth on Pulp Mill Waste Streams and Characterization of the Biodegradation Potential of Cultured Microbes

The kraft process is applied to wood chips for separation of lignin from the polysaccharides within lignocellulose for pulp that will produce a high quality paper. Black liquor is a pulping waste generated by the kraft process that has potential for downstream bioconversion. However, the recalcitrant nature of the lignocellulose resources, its chemical derivatives that constitute the majority of available organic carbon within black liquor, and its basic pH present challenges to microbial biodegradation of this waste material. Methods for the collection and modification of black liquor for microbial growth are aimed at utilization of this pulp waste to convert the lignin, organic acids, and polysaccharide degradation byproducts into valuable chemicals. The lignocellulose extraction techniques presented provide a reproducible method for preparation of lignocellulose growth substrates for understanding metabolic capacities of cultured microorganisms. Use of gas chromatography-mass spectrometry enables the identification and quantification of the fermentation products resulting from the growth of microorganisms on pulping waste. These methods when used together can facilitate the determination of the metabolic activity of microorganisms with potential to produce fermentation products that would provide greater value to the pulping system and reduce effluent waste, thereby increasing potential paper milling profits and offering additional uses for black liquor.

Industrial wastes can be collected and modified to analyze microbial growth. Lignocellulose extraction techniques provide components to analyze specific biodegradation ability. Gas chromatography-mass spectrometry identifies fermentation products of microorganisms grown on pulping waste. These methods determine the metabolic capacity of microorganisms to degrade pulping waste.

The kraft process is applied to wood chips for separation of lignin from the polysaccharides within lignocellulose for pulp that will produce a high ...

Design and Construction of an Urban Runoff Research Facility

As the urban population increases, so does the area of irrigated urban landscape. Summer water use in urban areas can be 2-3x winter base line water use due to increased demand for landscape irrigation. Improper irrigation practices and large rainfall events can result in runoff from urban landscapes which has potential to carry nutrients and sediments into local streams and lakes where they may contribute to eutrophication. A 1,000 m2 facility was constructed which consists of 24 individual 33.6 m2 field plots, each equipped for measuring total runoff volumes with time and collection of runoff subsamples at selected intervals for quantification of chemical constituents in the runoff water from simulated urban landscapes. Runoff volumes from the first and second trials had coefficient of variability (CV) values of 38.2 and 28.7%, respectively. CV values for runoff pH, EC, and Na concentration for both trials were all under 10%. Concentrations of DOC, TDN, DON, PO4-P, K+, Mg2+, and Ca2+ had CV values less than 50% in both trials. Overall, the results of testing performed after sod installation at the facility indicated good uniformity between plots for runoff volumes and chemical constituents. The large plot size is sufficient to include much of the natural variability and therefore provides better simulation of urban landscape ecosystems.

This paper describes the design, construction, and function of a 1,000 m2 facility containing 24 individual 33.6 m2 field plots equipped for measuring total runoff volumes with time and collection of runoff subsamples at selected intervals for quantification of chemical constituents in the runoff water from simulated home lawns.

As the urban population increases, so does the area of irrigated urban landscape. Summer water use in urban areas can be 2-3x winter base line water use ...

A Bending Test for Determining the Atterberg Plastic Limit in Soils

The thread rolling test is the most commonly used method to determine the plastic limit (PL) in soils. It has been widely criticized, because a considerable subjective judgment from the operator that carries out the test is involved during its performance, which may affect the final result significantly. Different alternative methods have been put forward, but they cannot compete with the standard rolling test in speed, simplicity and cost.
In an earlier study by the authors, a simple method with a simple device to determine the PL was presented (the &#34;thread bending test&#34; or simply &#34;bending test&#34;); this method allowed the PL to be obtained with minimal operator interference. In the present paper a version of the original bending test is shown. The experimental basis is the same as the original bending test: soil threads which are 3 mm in diameter and 52 mm long are bent until they start to crack, so that both the bending produced and its related moisture content are determined. However, this new version enables the calculation of PL from an equation, so it is not necessary to plot any curve or straight line to obtain this parameter and, in fact, the PL can be achieved with only one experimental point (but two experimental points are recommended).
The PL results obtained with this new version are very similar to those obtained through the original bending test and the standard rolling test by a highly experienced operator. Only in particular cases of high plasticity cohesive soils, there is a greater difference in the result. Despite this, the bending test works very well for all types of soil, both cohesive and very low plasticity soils, where the latter are the most difficult to test via the standard thread rolling method.

The traditional standardized test for determining the plastic limit in soils is performed by hand, and the result varies depending on the operator. An alternative method based on bending measurements is presented in this study. This allows the plastic limit to be obtained with a clear and objective criterion.

The thread rolling test is the most commonly used method to determine the plastic limit (PL) in soils. It has been widely criticized, because a ...

Evaluating the Effect of Environmental Chemicals on Honey Bee Development from the Individual to Colony Level

The presence of pesticides in the beekeeping environment is one of the most serious problems that impacts the life of a honey bee. Pesticides can be brought back to the beehive after the bees have foraged on flowers that have been sprayed with pesticides. Pesticide contaminated food can be exchanged between workers which then feed larvae and therefore can potentially affect the development of honey bees. Thus, residual pesticides in the environment can become a chronic damaging factor to honey bee populations and gradually lead to colony collapse. In the presented protocol, honey bee feeding methods are described and applied to either an individual honey bee or to a colony. Here, the insect growth regulator (IGR) pyriproxyfen (PPN), which is widely used to control pest insects and is harmful to the development of honey bee larvae and pupae, is used as the pesticide. The presenting procedure can be applied to other potentially harmful chemicals or honeybee pathogens for further studies.

Herein we present a method to feed pesticide contaminated food to both an individual honey bee and a beehive colony. The procedure evaluates the pesticide effect on individual honey bees by in vivo feeding of basic larval diet and also on the natural condition of beehive colony.

The presence of pesticides in the beekeeping environment is one of the most serious problems that impacts the life of a honey bee. Pesticides can be ...

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Microplastics act as vector of potentially toxic organic contaminants with unpredictable effects. This protocol describes an alternative methodology for assessing the levels of organochlorine pesticides adsorbed on plastic pellets and identifying the polymer chemical structure. The focus is on pressurized fluid extraction and attenuated total reflectance Fourier transform infrared spectroscopy.

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

The Effect of the Application of Thyme Essential Oil on Microbial Load During Meat Drying

Meat is a high protein meal that is used in the preparation of jerky, a popular food snack, where preservation and safety are important. To assure food safety and to extend the shelf life of meat and meat products, the use of either synthetic or natural preservatives have been applied to control and eliminate foodborne bacteria. A growing interest in the application of natural food additives for meat has increased. Microorganisms, such as Escherichia coli, contaminate meat and meat products, causing foodborne illnesses. Therefore, it is necessary to improve the meat conservation process. However, the use of essential oils when the meat is being dried has not been deeply studied. In this regard, there is an opportunity to increase the value of dried meat and reduce the risk of foodborne illnesses by applying essential oils during the drying process. In this protocol, we present a novel method of applying thyme essential oil (TEO) during meat drying, specifically in vapor form directly in a drying chamber. For evaluation, we use Minimal Inhibitory Concentration (MIC) to detect the number of harmful bacteria in the treated samples compared to raw samples. The preliminary results show that this method is a viable and alternative option to synthetic preservatives and that it significantly reduces microbial load in dried meat.

Microorganisms such as Escherichia coli that contaminate meat products cause foodborne illnesses. The use of essential oils in the meat drying process has not been deeply studied. Here, we present a novel method of applying thyme essential oil to meat during drying to reduce the microbial load in dried meat.

Meat is a high protein meal that is used in the preparation of jerky, a popular food snack, where preservation and safety are important. To assure food ...

Optimized Procedure for Determining the Adsorption of Phosphonates onto Granular Ferric Hydroxide using a Miniaturized Phosphorus Determination Method

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric hydroxide (GFH), with little effort and high reliability. The phosphonate, e.g., nitrilotrimethylphosphonic acid (NTMP), is brought into contact with the GFH in a rotator in a solution buffered by an organic acid (e.g., acetic acid) or Good buffer (e.g., 2-(N-morpholino)ethanesulfonic acid) [MES] and N-cyclohexyl-2-hydroxyl-3-aminopropanesulfonic acid [CAPSO]) in a concentration of 10 mM for a specific time in 50 mL centrifuge tubes. Subsequently, after membrane filtration (0.45 &#181;m pore size), the total phosphorus (total P) concentration is measured using a specifically developed determination method (ISOmini). This method is a modification and simplification of the ISO 6878 method: a 4 mL sample is mixed with H2SO4 and K2S2O8 in a screw cap vial, heated to 148-150 &#176;C for 1 h and then mixed with NaOH, ascorbic acid and acidified molybdate with antimony(III) (final volume of 10 mL) to produce a blue complex. The color intensity, which is linearly proportional to the phosphorus concentration, is measured spectrophotometrically (880 nm). It is demonstrated that the buffer concentration used has no significant effect on the adsorption of phosphonate between pH 4 and 12. The buffers, therefore, do not compete with the phosphonate for adsorption sites. Furthermore, the relatively high concentration of the buffer requires a higher dosage concentration of oxidizing agent (K2S2O8) for digestion than that specified in ISO 6878, which, together with the NaOH dosage, is matched to each buffer. Despite the simplification, the ISOmini method does not lose any of its accuracy compared to the standardized method.

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric hydroxide, with little effort and high reliability. In a buffered solution, the phosphonate is brought into contact with the adsorbent using a rotator and then analyzed via a miniaturized phosphorus determination method.

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric ...

Construction of a Low-cost Mobile Incubator for Field and Laboratory Use

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water quality. However, commercially available incubators are often costly, difficult to transport, not flexible in terms of volume, and/or poorly adapted to local field conditions where access to electricity is unreliable. The purpose of this study was to develop an adaptable, low-cost and transportable incubator that can be constructed using readily available components. The electronic core of the incubator was first developed. These components were then tested under a range of ambient temperature conditions (3.5 &#176;C - 39 &#176;C) using three types of incubator shells (polystyrene foam box, hard cooler box, and cardboard box covered with a survival blanket). The electronic core showed comparable performance to a standard laboratory incubator in terms of the time required to reach the set temperature, inner temperature stability and spatial dispersion, power consumption, and microbial growth. The incubator set-ups were also effective at moderate and low ambient temperatures (between 3.5 &#176;C and 27 &#176;C), and at high temperatures (39 &#176;C) when the incubator set temperature was higher. This incubator prototype is low-cost (&lt; 300 USD) and adaptable to a variety of materials and volumes. Its demountable structure makes it easy to transport. It can be used in both established laboratories with grid power or in remote settings powered by solar energy or a car battery. It is particularly useful as an equipment option for field laboratories in areas with limited access to resources for water quality monitoring.

This paper describes a method for building an adaptable, low-cost and transportable incubator for microbial testing of drinking water. Our design is based on widely available materials and can operate under a range of field conditions, while still offering the advantages of higher-end laboratory-based models.

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water ...

Measuring the Shape and Size of Activated Sludge Particles Immobilized in Agar with an Open Source Software Pipeline

Experimental bioreactors, such as those treating wastewater, contain particles whose size and shape are important parameters. For example, the size and shape of activated sludge flocs can indicate the conditions at the microscale, and also directly affect how well the sludge settles in a clarifier.
Particle size and shape are both misleadingly &#39;simple&#39; measurements. Many subtle issues, often unaddressed in informal protocols, can arise when sampling, imaging, and analyzing particles. Sampling methods may be biased or not provide enough statistical power. The samples themselves may be poorly preserved or undergo alteration during immobilization. Images may not be of sufficient quality; overlapping particles, depth of field, magnification level, and various noise can all produce poor results. Poorly specified analysis can introduce bias, such as that produced by manual image thresholding and segmentation.
Affordability and throughput are desirable alongside reproducibility. An affordable, high throughput method can enable more frequent particle measurement, producing many images containing thousands of particles. A method that uses inexpensive reagents, a common dissecting microscope, and freely-available open source analysis software allows repeatable, accessible, reproducible, and partially-automated experimental results. Further, the product of such a method can be well-formatted, well-defined, and easily understood by data analysis software, easing both within-lab analyses and data sharing between labs.
We present a protocol that details the steps needed to produce such a product, including: sampling, sample preparation and immobilization in agar, digital image acquisition, digital image analysis, and examples of experiment-specific figure generation from the analysis results. We have also included an open-source data analysis pipeline to support this protocol.

The size and shape of particles in activated sludge are important parameters that are measured using varying methods. Inaccuracies arise from non-representative sampling, suboptimal images, and subjective analysis parameters. To minimize these errors and ease measurement, we present a protocol specifying every step, including an open source software pipeline.

Experimental bioreactors, such as those treating wastewater, contain particles whose size and shape are important parameters. For example, the size and ...