Biodegradable Pots - Replacing agricultural and horticultural plastics on campus

Executive Summary:

This project proposes the production of molded biodegradable pots to replace agricultural and horticultural plastic pots on campus. These pots will be made using switchgrass and brewer’s spent grain, both of which are readily available to the Paper and Bioproducts Center located in the basement of Bloedel Hall; a floor layout of this lab can be found attached to this proposal in Figure 2. The Paper and Bioresource Center focuses on conversion of raw bio-materials into pulp, paper, products, and fuels; making it a synergistic fit for this new sustainable molding technology. A current sustainability issue is resolved by fabricating these pots with up to 60% spent grains, preventing these grains entering landfill. Currently, a team of 5 Bioresource Science and Engineering (BSE) students has been established to begin production of these biodegradable pots, with the intent of creating a precedent of sustainable products on the UW campus. Our long-term goal is to provide the campus with sustainable alternatives to disposable plastics across campus organizations, research facilities, and classrooms wherever possible. 

Student Involvement:

This project will be entirely student-led by undergraduates in BSE, with support provided by ESRM students involved in SER. It is likely that student volunteers and student-employees involved will be student members of the Technical Association of the Pulp and Paper Industry (TAPPI), as this machinery is directly applicable to their industry. These students will be the ones in charge of production, quality control, and continued campus outreach, and will be sought out beginning in Autumn quarter 2017.

Additionally, production of these biodegradables will be integrated into BSE curriculum as a permanent part of Paper and Bioresource Center. This includes an introduction to the machinery in 200-level BSE courses, to prepare these process engineering students to study a sustainable production line later in their undergraduate career. Learning opportunities will continue into the students’ senior year during BSE 436 (a papermaking laboratory course) where the product can be analyzed and improved upon. The design-based BSE 480-481 courses is where students will explore design economics and perform a full LCA on the process. In total, the incorporation of this process into the curriculum accounts for 40 students consistently working on production, analysis, and improvements. Perhaps the most important stakeholders to this project are the future students who will gain valuable hands-on experience with the production of sustainable products. This technology will continue to be highly applicable to industry as more plastics are being replaced by molded pulp products.

Additionally, a possible avenue for student involvement is opening an opportunity for an ESRM student to take data on the end-use of the product’s life. This will provide valuable information for the production and improvement teams, and more data for the project’s progress. 

Education & Outreach:

To increase the market size after production, we plan to give away samples of our product to applicable campus groups. This involves contacting UW grounds, botanic gardens, and possibly food vendors on campus to see if our products are viable replacements for their plastics. In addition, there are several BSE student group-related events in which free samples and/or demonstrations can increase exposure of our product. For example, TAPPI holds an annual Christmas fundraiser, during which our products can be sold to the public. In addition, we can partner with sustainability-focused booths and tables at campus events in Red-Square and have them feature our product.

In terms of education, the technical process details related to both manufacturing and raw materials can be integrated into BSE curriculum across multiple classes and grade levels, involving freshman to senior students in sustainable production processes. ESRM/SER students, and those taking ESRM 412 as detailed in the ‘Student Involvement’ section will also be directly impacted in the education of biodegradable containers as well. We will begin incorporating process information into relevant class starting in Autumn quarter 2017 after production has begun. 

Environmental Impact:
  • Energy Use
  • Food
  • Living Systems and Biodiversity
  • Waste
  • Water
Project Longevity:

We currently have a start-up team of five BSE undergraduates that intend to work on this project until their graduation in June of 2018. This means the preparation and start-up will be overseen by these five students, and continued by the BSE and UW SER-affiliated students mentioned above. Pulp-molding production gives these students additional access to self-sustaining design projects, an asset that will always be in demand in the BSE program. Currently, prototype pots have been fabricated and characterized at the bench-scale. The next steps post-funding are ordering the molding machine parts and assessing physical utilities once the equipment arrives. Though we have attached the approval forms from grounds and facilities to install, it’s likely that we will contract-out the installation of equipment given the complexity of current infrastructure in the Paper and Bioresource Center. Figure 2 has the finalized location of the mold machine on the floor layout as approved by Kurt Haunreiter. As of now, the following are assured: supplier, start-up team, potential market through UW SER, raw materials, space, and infrastructure. Figure 1 shows a chart of the current start-up timeline through the end of August. Once the product is produced in a sustainable fashion, outreach and education of these campus biodegradable products can begin.

Environmental Problem:

Many organizations on campus work with plants for landscaping, agriculture, and horticulture research. Although the end-uses strive to be a sustainable as possible, currently, most of these plants are housed in disposable plastic plant pots. These plastic pots are often washed out for re-use using excess water and possibly bleach, creating hazardous runoff. By offering a biodegradable plant pot, this project hopes to decrease the carbon footprint, water-use, and waste associated with the use of disposable pots. At the same time, soil health and plant growth will be improved by nutrients in the pot that originate from pulp, brewer’s spent grain, and black liquor fertilizer. Finally, the molding machine’s use to make the pots will serve as an example of sustainable manufacturing on a pilot scale.

Environmental benefits of these biodegradable pots include:

  • Better aeration for roots
  • Improved growth and survival
    • Decay of the pot allows roots to grow out into surrounding soil whereas planted (roots are unable to expand when planted from plastic containers, thereby reducing growth and survival [1]).
  • Prevention of transplant shock
  • Less fertilizer needed compared to peat pots, reducing possibility of burnt roots [2]
  • Increased nutrients in the soil through the use of brewer’s spent grain – this reduces the amount of grain in landfills
    • Study showed distillery waste combined with peat compost enhanced the contents of nitrogen, phosphorus, potassium, calcium, and sodium in the soil [3].
    • Increasing distillery waste by 25% has a positive effect on seedling height [3].


[1]M. Theuer, "Plant pot that fertilizes when it biodegrades", US 20050188612 A1, 2017.

[2]J. Pullen, "Cellulosic molded transplanter pot or other products containing bagasse components", US 3102364 A, 2017.

[3]M. Bustamante, C. Paredes, R. Moral, E. Agulló, M. Pérez-Murcia and M. Abad, "Composts from distillery wastes as peat substitutes for transplant production", Resources, Conservation and Recycling, vol. 52, no. 5, pp. 792-799, 2008.

Explain how the impacts will be measured:

While production start-up is our priority, monitoring the impacts of the pots is an important aspect of this project. There are three possible pathways for data collection; all of them are entirely student-led and could directly compare CO2 emissions, water consumption, waste, and soil/plant health related to our biodegradable products in comparison to that of plastic containers. Since the entire process from raw bio-materials to end-product is conducted on campus, a full life-cycle-assessment (LCA) of our products can be conducted by these students.

  1. The first monitoring method is providing an opportunity for data collection for an Environmental Science & Resource Management (ESRM) student’s capstone project via our partnership with UW Society of Ecological Restoration (SER). This will begin after production once Autumn quarter begins in September 2017.
  2. Secondly there is an opportunity for this project to be analyzed by Bioresource Science and Engineering (BSE) students in the BSE 426 and 436 lab classes. In both cases, at least one life-cycle-assessment can be conducted by a group of students each year, in addition to process efficiency modifications.
  3. Lastly, as per the CSF’s suggestion, integration with ESRM 412 “Native Plant Production” could be a valuable source of research for efficacy regarding the growth of native plants in our pots. This data could then be fed to the BSE students working on production to continuously improve product qualities.
Total amount requested from the CSF: $70,000
This funding request is a: Grant
If this is a loan, what is the estimated payback period?:


Itemized Budget - Biodegradable Pots
NameFixed or VariableQuantityUnit Price (quantity included)Reorder necessary?
Machinery - Directly from quote
Operation PlatformFixed11285.72No
Control Cabinet for pulping and forming systemFixed13587.32No
Reciprocating forming machineFixed19142.89No
Auto drain systemFixed13428.59No
Hot-pressing machineFixed16031.77No
Hot press and forming mold X4Fixed418095.28No
Parts shippingFixed14000No
Other - Estimated Costs
Installation, (infrastructure wiring, piping)Fixed115000No
Sprayer (for black liquor fertilizer)Fixed12500No
Chemicals (release agents, shipping)Variable11000Once per year
Raw materials and shippingVariable11000Variable
Equipment sparesVariable12000Variable

Non-CSF Sources:

Non-CSF Funding SourcesCoverage
Paper and Bioresource Center maintenance budget Chemicals, raw materials, and spare parts beyond 1st year of operation
Project Completion Total: $70,000


TaskStartEstimated Completion DateDuration (Days)
Mould Machine4/01/178/01/17122
Purchase Order6/01/176/02/171
Install MCC7/01/177/15/1714
Pull Wire7/10/177/05/174
Equipment Install8/05/178/14/179
Install Auxillary Equipment8/05/178/10/175
Install Molding Unit8/07/178/14/177
Procedure Development8/05/178/10/175
Potential Problem Analysis8/01/178/03/172
Schedule "A" items8/03/178/04/171
Start up8/14/178/25/1711
Machine CCO (Construction Check Out)8/14/178/18/174