From Freeway to Fragrance

Problem Statement

Design Approach

Scale Up

Timeline

Bench Scale Results

Economic Analysis

The purpose of the project was to design a useful, economically feasible add-on process with as many specifications as possible to an existing plant that creates tire oil as a waste product. The goal is to remove limonene from the waste tire oil stream, improving the profit of the plant and the quality of the remaining oil.

The most economical method to recover limonene from waste tire oil is to thermally crack the limonene into isoprene and later reform the limonene by dimerization. The advantage of this method is the formation of light chemicals in an otherwise heavy stream in the limonene reactor and the formation of heavy chemicals in an otherwise light stream in the isoprene reactor. The difference in the component boiling points in each stream makes purification of the final product simpler and reduces operating costs.

Product: Limonene (80%, Industrial)Basis (gal/hr) 3Operating Time (h/yr) 7440Sales Price ($/gal) $77

Product: Improved Reklaim OilBasis (L/hr) 62Operating Time (h/yr) 7440Sales Price ($/gal) $1

Direct-Production Cost $373,000 Fixed Charges $325,000 Plant Overhead Costs $140,000

Factory-Manufacturing Cost $838,000

General Expenses $400,000 Total Product Cost $1,238,000

Total Income $2,180,000

Fixed-Capital Investment $2,368,000 Working Capital $552,000

Total Capital Investment $2,920,000

Gross Earnings Before Taxes $942,000 Net Profits after 35% taxes $612,300 Average Annual ROI 21%

Payout Time (years) 2.0Net Present Worth $2,400,000 Discounted Cash Flow ROI 23.1%

Process ConversionCracking Limonene to Isoprene 95%Dimerizing Isoprene to Limonene 16%

Months 1 2 3 4 5 6 7 8 9 10 11 12

Additional Lab Scale Experiments

Site Analysis

Final Pilot Plant Sizing

Permitting

Order Parts and Equipment

Construction

Start-Up

Monitoring

Optimization

Recovering Limonene From Recycled Tires

Isoprene to Limonene Setup

Bench Scale Cracking Apparatus

Team MembersTianna Drew

Amanda EagleBrice SumnerSara Sumner

AdvisorsDr. M.F. Roll

Dr. D.C. Drown

Feed: 65 gallons per hour, 5% limonene, $0.37/gallonLimonene Product: 3 gallons per hour, 80% limonene, $77/gallonImproved Waste Oil: 62 gallons per hour, 0% limonene, $1/gallon

Sponsors:

Major John Riggins, Retired USAF