Progress 07/01/22 to 08/31/23

Outputs
Target Audience:Our target audience is twofold. First are domestic municipalities that use facultative and oxidation algae pond technology for their wastewater treatment needs. There are an estimated 8000 of these ponds systems within the US. Our initial focus will be on developing a network of facilities in California; but will eventually also include clusters of facilities in other regions of the US. We will focus is on facilities that are under regulatory pressure for exceeding their permitted discharge limits. Within the US, we estimate this to be roughly 2400 domestic facilities based on available databases published by the USEPA. Within this category, our initial focus has been onfacilitieswithin California's State Water Board Region 5 where there are nearly 180 ponds systems within the region permitted by the State Water Board. Our preliminary analyses of available databases suggest that more than 50 of these systems have had at least 50 discharge violations in the last 5 years. We have contacted 43 of them and are learning about the challenges they face and working to educate facility staff on the opportunity to beneficially reuse the algae from their pond systems. The next targeted audience are the bioproduct manufacturers to whom we will sell the dried algae biomass. At this stage we are working closely with two bioproducts manufacturers, Heliae Development LLC who makes biostimulants from microalgae for agricultural applications and a bioplastic resin producer, Algix LLC. Algix's 2022 demand for biomass was 500 tons and is expected to grow exponentially. This expected growth is in large part due to the recently passed Environmental Social Governance regulations in the European Green Deal's Circular Economy Action Plan that was passed late in 2022. These new regulations will require bio-based plastics to be sustainably sourced and will prioritize organic waste and by-products as feedstock. Currently most other bioplastic technologies depend on high molecular weight carbohydrates and are often in competition with food resources such as corn, sugarcane, tapioca etc. An additional niche of interest within the greater bioproduct market is the agricultural sector and the production of biofertilizers and biostimulants. Crop biofertilizers and biostimulants have both economic and environmental benefits. They support crop health and productivity in ways that chemical fertilizers do not, while avoiding fossil fuels in their manufacture. Biofertilizers and biostimulants are two major overlapping categories of natural organic bioproducts applied to soils, seeds, or foliage to increase crop productivity. As opposed to other sources of organic material such as food waste and bacterial biosolids, the N-P-K ratio of algae is nearly ideal for fertilizers and fosters health, aggregation, and microbial community within the soil. We continue to actively pursue this market as we believe it stands to offer the most benefit to rural communities and has the potential to handle moist material which could significantly reduce the cost of processing. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project Principal Investigator attended the California Association of Santitation Agencies (CASA) Partnering for Impact conference in June of 2023 to learn more about other innovative biosolids handling practices within the municipal wastewater industry as a whole within the state of California. How have the results been disseminated to communities of interest?Meetings with stakeholders took place over the duration of the project and final project presentations for each participating community are currently being scheduled. Further dissemination will take place through participation in California Water Environment Association meetings throughout the Central Valley of California. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The work associated with this project determined the use of waste grown algaeas a feedstock for bioproducts is a feasible endeavor. The suitability of the material for use in bioplastics was demonstrated analytically for seven of the nine tested samplesbased on several key metrics of the algae including, moisture, ash and protein content and the presence of odor compounds. The use of waste derived algae as a feedstock for biostimulants was also determined to be a plausible path forward, in part because of algae's past demonstrated biostimulant properties and also due to the ability to use a higher moisture content feedstock, thereby having the potential to reduceCAPEX and OPEX of the centralized processing facility. The technical and economic viability of the proposed concept was investigated through bench scale and some short duration full scale trials of several different harvesting and dewatering technologies as well as through biomass productivity estimations using representative samples from four facilities. The results of these trialswere combined with feedback from stakeholders to identify the optimal equipment and installation design for the most number of prospective facilities. Costs of this design were determined for facilities of various sizesand theinstalled cost was estimated for the Hilmar facitlity in the California Central Valley. The expansion of participating facilitiesfrom the initial 5 to include anadditional ten facilities would put the business case on a trajectory toward generating3500 tonnes of algae biomass annually. Given the average size and algae production capacity of pond systems in this region, achieving 4000 tonnes annualy would requirean additional 20-25 systems to join the network. Certainly,expansion to this size is an intensive undertakingrequiringsignificant outreach and marketing. However,given the economic and environmental benefits described in more detail below and positive feedback during the phase I work, it is promising path with environmental and economic benefits to the communities being served. In terms of the economic feasibility and benefits to the rural communities in which these wastewater treatment pond systems operate;the costs of this proposed harvesting-dewatering + off site haulingand ultimately drying solution were found to actually be less than if communities continued in the business as usual scenario and were faced with the maintenance costs associated with not harvesting the biomass and/or permit exceedance violations. While the up front costs of installing the harvest and dewater equipment are obviously more than the immediate costs associated with base caseoperations, the longer terms costs associated with having to dredge the ponds more than make up for the up front and investment and maintenance costs. This is evident when comparing the 25 year net present cost of $2,919,050 for the harvest + dewater upgrade to $3,125,000 associated with the dredging and the potential for permit violations, driving the 25 yr net present cost up to $3,812,500. While these differences in costs over 25 years may beminimal, there is still long term savings associated with the upgrade. Moreover, the improvement in water quality of the effluentand estimated 82% reduction in greenhouse gas emissions confer significant environmental beneftis on top of the reduction in long term cost of operationsto the community. The feasibility of the centralized processing facility, particularlythe costs associated with drying the algae biomass to < 10% moisture content is dependent eventually on a minimum of 4000 tonnes of biomass annually. To achieve this quantity of biomass, the network is heavily dependent on three of the largest pond systems within the region. One avenue currently being investigatedto minimize the risk associated with this dependence, is to further explore the possibility of upcycling to products that do not require the biomass to be so dry This path forward has a number of dependencies that were outside of the scope of this phase I project but will form the basis of our proposed Phase II work. These include but are not limited to technical aspects related to dewatered algae storage and stabilization, the effect of storage time and stabilization techniques on biostimulant performance, the types of coagulants and polymers required for dewatering and their subsequent effect on biostimulant performance. Partnership models for this particular pathway will also require further investigation as they would be dependent on the biostimulant production facility being co-located with the biomass aggregation facility. This is because shipping material that is 80% water over more than 40-100 miles would likely be cost prohibitive. In addition to the potential for this pathway to be more financially stable, and perhaps even more important, are the ancillary benefits associated with the local production and use of a regenerative agricultural product within rural regions of this country, where the benefits are immediately impactful environmentally and economically.

Publications