PHOSPHORUS REMOVAL FROM ETHANOL CONDENSED THIN STILLAGE TO PRODUCE A PROFITABLE, RECYCLED FERTILIZER, WHILE IMPROVING SURFACE WATER QUALITY.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: SMALL BUSINESS GRANT
• Reporting Frequency: Annual
• Accession No.: 1003325
• Grant No.: 2014-33610-22116
• Cumulative Award Amt.: $449,800.00
• Proposal No.: 2014-02755
• Project Start Date: Sep 1, 2014
• Project End Date: Aug 31, 2016
• Grant Year: 2014
• Program Code: [8.4]- Air, Water and Soils

Recipient Organization
Kansas Environmental Management Associates, LLC
6031 SW 37th Street
Topeka,KS 66614

Performing Department
(N/A)

Non Technical Summary
The expansion of the ethanol industry has led to the wide spread availability and economic pricing of distillers grains (DGS), resulting in significant amounts of DGS being commonly included in animal diets. DGS typically replaces corn and protein supplements in the ration, but is has a much higher phosphorus concentration than corn. Therefore, the inclusion of DGS in livestock rations can significantly increase the phosphorus content in the excreted manure. Reducing the concentration of phosphorus in DGS would reduce the amount of excess phosphorus being fed to livestock, thereby decreasing any risk of surface water pollution from manure phosphorus.This project aims build upon the success of the Phase I project by conducting further research and development aimed at recovering excess phosphorus from ethanol condensed thin stillage (CTS). The system will remove soluble phosphorus from CTS, by converting it to the insoluble magnesium phosphate compound. The removed phosphorus would be a useful fertilizer for field crops or horticultural use. Similar technology has already been successfully used to remove phosphorus from liquid manure at confined animal feeding operations. Removing phosphorus at the ethanol plant would be more efficient, and impact a larger number of livestock operations at minimal (if any) cost to the livestock producer. Phase I results indicate that a reduction of soluble phosphorus in the CTS by 72% could decrease the excreted phosphorus at a beef feedlot by 36% when fed at 40% dry matter inclusion rate in common feedlot rations. There is no other beef feedlot management practice or technology available to reduce the excreted phosphorus so substantially while maintaining the same ration.This project will determine the reactor configuration, equipment needs, and operating conditions required for successful operation at an ethanol plant, as well as determine the fertilizer production at those optimal settings and normal conditions. The project will also test the fertilizer efficacy relative to common commercial fertilizers. Successful completion of the project would put KEMA in a position to license the technology for full-scale, commercial production.

Animal Health Component

45%

Research Effort Categories

Basic

15%

Applied

45%

Developmental

40%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
133	0210	2000	40%
133	0210	2010	30%
133	0210	2020	30%

Knowledge Area
133 - Pollution Prevention and Mitigation;

Subject Of Investigation
0210 - Water resources;

Field Of Science
2010 - Physics; 2020 - Engineering; 2000 - Chemistry;

Keywords

distillers grain

ethanol

fertilizer

phosphorus reduction

Goals / Objectives
The projects technical objectives are:1. Determine pilot reactor configuration, equipment needs, and operating conditions required for successful integrated operation at an ethanol plant.2. Determine the fertilizer production based on the optimal magnesium amendment form and rate, the optimal reactor configuration, and the normal operating conditions.3. Determine the recovered phosphorus fertilizer efficacy relative to common phosphorus fertilizers.

Project Methods
For the laboratory and pilot phosphorus recovery experiments the design of the experimental matrix and analysis of results will be performed using software for Design of Experiments (Design-Expert 8.0.3, StatEase Inc.). Design-Expert software offers two level factorial screening designs, general factorial designs, response surface method (RSM) techniques, mixture design techniques, and the ability to do combined designs with process factors, mixtures components and categorical factors. Influent and effluent samples will be collected for each condition/replication and analyzed for the following: a. Total Phosphorus, b. Soluble Phosphorus, c. Soluble Magnesium, d. Percent Total Solids. The Total Phosphorus, Soluble Phosphorus, and Soluble Magnesium analysis will be performed on-site. Recovered phosphorus precipitate fertilizer samples will be collected and shipped off-site for analysis. Each condition/replication will be analyzed for: a. Total Phosphorus, b. Total Magnesium, c. Mineral Type.For the greenhouse fertilizer experiments, the study will be set up per soil as a two factor factorial (soil type, and rate) completely randomized block design (RCBD) with four replications. For the field experiments, the experimental design will consist of a factorial in a randomized complete block, with a factorial combination of 3 fertilizer sources and 4 rates and replicated 3 times. The experimental plan may be modified based on the results of the greenhouse trials. For both the greenhouse and field trials, statistical analysis will be completed using the PROC GLIMMIX procedure in SAS 9.2.

Progress 09/01/14 to 08/31/16

Outputs
Target Audience:Ethanol production managers and personnel involved in corn oil recovery from ethanol sidestreams. Changes/Problems:During this reporting period a change was made to not pursue fertilizer efficacy testing as was previously planned. Although the budgeted funds for this task had not been expended, it would have required a project extension, and seemed fruitless given the nonprofitable fertilizer production estimate that had been determined as a result of the pilot testing. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Final results have not been dessiminated at this time. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? This project aims build upon the success of the Phase I project by conducting further research and development aimed at recovering excess phosphorus from ethanol condensed thin stillage (CTS). The system will remove soluble phosphorus from CTS, by converting it to the insoluble magnesium phosphate compound. The removed phosphorus would be a useful fertilizer for field crops or horticultural use. Similar technology has already been successfully used to remove phosphorus from liquid manure at confined animal feeding operations. Removing phosphorus at the ethanol plant would be more efficient, and impact a larger number of livestock operations at minimal (if any) cost to the livestock producer. Phase I results indicated that a reduction of soluble phosphorus in the CTS by 72% could decrease the excreted phosphorus at a beef feedlot by 36% when fed at 40% dry matter inclusion rate in common feedlot rations. There is no other beef feedlot management practice or technology available to reduce the excreted phosphorus so substantially while maintaining the same ration. The Phase II project is complete. The following describes progress towards the specific technical objectives: Technical Objective 1. Apilot reactor was built and tested during the reporting period. The configuration was determined prior to the build and optimized during testing. The pilot reactor equipment sourcing and construction took place primarily during the first nine months of this reporting period, with most of the testing taking place during the last 3 months. Data was collected and analyzed regarding system performance. The project confirmed that up to 98.6% of the dissolved phosphorus could be converted to a solid form using the pilot reactor. Unfortunately, the reaction time was significantly longer than Phase I testing had predicted, requiring a longer residence time in the reactor, and therefore, either a larger reactor, or a multi-stage reactor. While that was anunpredicted problem, it can be successfully dealt with, and was during pilot testing. It does however negatively effect the economic model, by driving up the cost of the treatment system. However, the larger problemthat was encountered was thedifficulty separating the produced phosphorus solids. The sizeof the solid particles produced in the scaled-up pilot system(5-50 microns)were significantly smaller thanthe particle size produced in the bench-scale system (20-60 microns).Only 25% of the solids grew to a size largerer than 25 microns, which made the hydrocyclone less efficient at recovering the produced solids.The hydrocyclone wasonly able to recover 15-25% of the phosphorus-rich solids, while the remaining75-85%remained in the thin stillage as suspended solids. Thiswas a negative finding and a significant one. the econimic modelwas basedon recovering a higher percentage of thephosphorus solids for sale as a fertilizer. Technical Objective 2. The fertilizer production (17% phosphorus concentration)is estimated to be 810 tonsper year from a 55 million gallon per year ethanol plant. This is less than half of the previously estimatedannual fertilizer volume based on Phase Idata.The lower production is a result of lower than predicted solids recovery, described above. Atcurrent prices this is not a profitable production rate. Technical Objective 3. Recovered phosphorus efficacy was not evaluated during this period. Due to the significantly lower thanprofitable fertilizer production, it was determined that a project extension (which would have been necessary) was not warranted to complete the efficacy trials on the recovered solids.

Publications

Progress 09/01/14 to 08/31/15

Outputs
Target Audience:Ethanol production managers, and personnel who oversee the corn oil recovery and distillers grainsmarketing at ethanol plants. Changes/Problems:More bench-scale work has been performed in preparation for pilot testing than originally planned. Early pilot preparation work indicated a need for additional bench-scale work prior to pilot testing, and this has delayed constructing andtesting the pilot system. This bench-scale work has been fruitful, allowing for more focused pilot testing, in terms of operating parameters/conditions. It has also resulted in the pilot system being constructed as a batch system rather than a continuous system. This will ease operation and testing, without compromising results. Results to date, from bench-scale work and modeling, indicate greater magnesium use than previously estimated, and a need to account for changes in the fat/oil characteristics as a result of the treatment process. Changes to the fat/oil profile could affect feed value of the remaining distillers grains. Results also indicate a likelyhood for small fertilizer particles to form, increasing the importance of hydrocyclone optimization for fertilizer removal. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Preliminary results have been shared with the cooperating ethanol plant. At this time that is the extent of the dissemination. What do you plan to do during the next reporting period to accomplish the goals?The pilot system is currently under construction. During the next reporting period its construction will be finished and the pilot testing will be completed. This will allow for further fertilizer testing, possible patent application(s), and for sharing the results with the broader ethanol industry.

Impacts
What was accomplished under these goals? This project aims build upon the success of the Phase I project by conducting further research and development aimed at recovering excess phosphorus from ethanol condensed thin stillage (CTS). The system will remove soluble phosphorus from CTS, by converting it to the insoluble magnesium phosphate compound. The removed phosphorus would be a useful fertilizer for field crops or horticultural use. Similar technology has already been successfully used to remove phosphorus from liquid manure at confined animal feeding operations. Removing phosphorus at the ethanol plant would be more efficient, and impact a larger number of livestock operations at minimal (if any) cost to the livestock producer. Phase I results indicated that a reduction of soluble phosphorus in the CTS by 72% could decrease the excreted phosphorus at a beef feedlot by 36% when fed at 40% dry matter inclusion rate in common feedlot rations. There is no other beef feedlot management practice or technology available to reduce the excreted phosphorus so substantially while maintaining the same ration. The Phase II project is still in progress, thus is still working towards accomplishing the technical objectives and overall goal. The following describesprogress towards the specific technical objectives: Technical Objective 1. The pilot reactor configuration and equipment needs have been determined and KEMA is in the process of acquiring the equipment and supplies needed for pilot testing. The operating conditions have also been determined based on the bench-scale work and will be tested at the pilot scale once the reactor is built. Technical Objective 2. The fertilizer production has been estimated based on bench-scale work and will be validated once the pilot scale system is built. Technical Objective 3. The fertilizer efficacy has been tested in the greenhouse, but results are not yet available.

Publications