Peter and I traveled to Dar es Salaam this past Tuesday, February 4th. After an hour long taxi ride, we became well acquainted with the city’s traffic-jammed streets filled with vendors weaving between trapped vehicles and peddling everything from peanuts to giant stuffed animals to the unhappy drivers. Eventually, we made it to the Safari Inn, where we established basecamp (and enjoyed the luxury of consistent air conditioning!) for the next three days.
The next day, we got up bright and early to catch our taxi to the University of Dar to meet Dr. Rajabu, a senior lecturer in the energy engineering department and longtime collaborator with DHE since the rocket stove project. There, we also got to meet Christian “Rui” Lohri, a researcher from the Swiss Federal Institute of Aquatic Science and Technology, who was serving as a co-advisor for two of Dr. Rajabu’s master students, Adam and Elia. Despite struggling to find the Engineering College (our taxi driver, Salim, had to ask the local residents for directions), we arrived just in time to sit in on their weekly project meeting.
For their master’s work, both students are focused on developing low-cost processors for the drying and carbonization steps of converting waste biomass into charcoal. Adam’s project is a solar powered biomass dryer that uses a solar collector to heat air being drawn through a drying rack by an electric-powered fan. The solar collector also has an insert for a charcoal stove so that air can be heated during cloudy days. Elia’s project is a carbonizer made of a brick and a rotatable oil drum. Basically the rotating mechanism makes the process more efficient by using the produced pyrolysis gases to make the process self-sustaining.
After the project meeting, we had a quick lunch before we hopped into Dr. Rajabu’s car to take a bumpy road trip through Dar’s mountainous back-roads to visit several of the briquetting sites in the city. The first was a technology farm run by Tatedo (Tanzania Traditional Energy Development and Environment Organization) showcasing several batch carbonizers including dirt mounds and large scale brick-and-oil drum retorts, greenhouse biomass driers, and motorized briquetting processors such as a briquette extruder, and “pillow case” briquette press. Afterwards, we stopped by ARTI (Appropriate Rural Technology Institute) Energy’s Tanzania headquarters, where we got to see their oil drum TLUD carbonizers (essentially big scale versions of the demonstration TLUD on campus), and their hand-powered briquette extruders. To top off the visit, we talked with the executive director, Nachiket W. Potnis, and one of the program officers about their business model. ARTI expects to produce and sell 4000 tons of charcoal by the end of the year! It’s exciting to see at these places how charcoal briquetting can be successful and make an impact at a large scale.