Biosolids are the nutrient-rich, organic by-product of the wastewater treatment process which can be recycled and used to enhance soil conditions.
The USDA Certified BioPreferred Product Label is designed to provide useful information to consumers about the biobased content of the product. The label assures a consumer that the product contains a USDA-verified amount of renewable biological ingredients.
BioPreferred products provide all the benefits as conventional products; they are cost-comparative, readily available (made by small companies and large corporations), and perform as well or better than their petroleum containing counterparts.
Products need to meet a minimum biobased content set by the USDA. The manufacturers of these products must test the biobased content at an independent, third party laboratory.
When Class A, exceptional quality (EQ) biosolids are produced using a drying or thermal process, the end product can often contain varying amounts of dust. A dusty product can create issues related to uneven spreading patters, drifting and improper  nutrient placement.
When biosolid fertilizer is pressed through specially designed dye plates, the friction of the process produces heat. At the proper temperature, the naturally occurring lignen in the biosolids is released to help in the formation of the pellet. Lignen is a complex organic polymer found in the tissue of most plants, therefore it is naturally present in biosolids.