Quimico

International Journal for Service Learning in Engineering Vol. 7, No. 1, pp. 69-92, Spring 2012 ISSN 1555-9033

Wastewater Treatment for a Coffee Processing Mill in Nicaragua: A Service-Learning Design Project
Michael D. Marsolek
Assistant Professor Civil and Environmental Engineering Seattle University

Patrick K. Cummings
BS Candidate Civil and Environmental Engineering Seattle Universitymarsolem@seattleu.edu

patrickc@seattleu.edu Michael Wayne
BS Candidate Civil and Environmental Engineering Seattle University

Joshua T. Alcantara
BS Candidate Civil and Environmental Engineering Seattle University

Josh.Alcantara@gmail.com

mikolwin@yahoo.com

Luis F. Quintero
BS Candidate Civil and Environmental Engineering Seattle University

Carlos Vallejos
Coordinator of Natural Sciences Facultyof Science, Technology, and Environment University of Central America – Managua

luisquintero2@me.com

carlosv@ns.uca.edu.ni

Charles F. Jackels
Professor Computing and Software Systems University of Washington – Bothell

Susan C. Jackels
Professor Department of Chemistry Seattle University

jackels@u.washington.edu

sjackels@seattleu.edu

Abstract - An undergraduate capstone design project teamconsisting of candidates for the BS degree in Civil and Environmental Engineering and faculty designed a wastewater treatment facility for a coffee processing mill in rural Nicaragua. The team visited Nicaragua to interview the client community, survey the actual site, and hold discussions with local development agencies, agricultural cooperatives, and potential contractors. Three alternativedesigns were developed, and the community chose one involving a settling basin and a series of three infiltration pits. The treatment system is expected to meet MARENA discharge standards for pH, turbidity, and chemical oxygen demand (COD) of discharge wastewater. The project team further secured sufficient funding from Tetra Tech, an environmental consulting firm, to build the coffee mill and thewater treatment facility. On a subsequent visit, the mill and treatment facility were seen to be well constructed and functional. Several important lessons regarding international service learning design projects were learned: the need for a large cost overrun buffer; the utility of having contributors on-site during both important decision making stages and construction; the value of working withlocal organizations to facilitate remote work projects; the possibility of private sponsorship and partnership for charitable projects; and the need to work with the community to design and select appropriate technologies. Index Terms: green coffee, coffee processing, wastewater treatment, engineering design, service learning

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International Journal for Service Learning in Engineering Vol. 7,No. 1, pp. 69-92, Spring 2012 ISSN 1555-9033

INTRODUCTION Strongly fluctuating world market prices for green coffee have long posed difficulties for small-scale coffee producers in developing nations. Over the period 1970-2010, for example, world coffee prices varied greatly, with the annual average ICO Composite Indicator Price fluctuating1,2 between an all-time high of $2.29/lb in 1977 to lessthan $0.46/lb in 2001. After languishing well below $0.60/lb during the early 2000s, it only rose to above $2/lb during 2011i. The period during the early 2000s, when coffee prices were very low, became known as the “Coffee Crisis”.3 One response to the widespread economic displacement and poverty of the Coffee Crisis was to emphasize production of higher quality coffee that also bore internationalcertifications such as Fair Trade and Organic. Success in these specialty markets, drawing prices as much as 40% above those of the commodity markets, required progress in two areas: 1) Adaptation of farms and methods to comply with the requirements of the desired certifications; and 2) Production of coffee of sufficiently high quality that it will be purchased. Certification alone does not...