Dispatch from Helsinki

In the 1970s, when trash-collecting pneumatic tubes were introduced, Finnish municipalities took a pass on incorporating them into the infrastructure. I am not sure why this is. It could have been timing. Tapiola, just west of Helsinki, a highlight of postwar new town planning, was conceived a decade before before Sweden’s million homes program (1965–74) first adapted pneumatic collection at a municipal scale. Or it could have to do with economics, or housing policy. Finland’s welfare state was less developed than its Scandinavian neighbors’.

Kruunuvuorenselkä, a Helsinki new town that utilizes pneumatic waste systems

Somehow Finland also missed the second wave, thirty years later, when tubes were installed in eco-neighborhoods and historic city centers in Europe and in new high-rise cities in Asia and the Middle East. Despite this, Finland may have a hand in what could someday be seen as pneumatic waste-collection’s third wave: tube networks that make modern garbage collection infrastructure so accessible that it becomes as ubiquitous as the bentwood furniture Finnish designers brought to living rooms in the 1950s and ’60s. A Finnish company, MariMatic, recently developed a new generation of pneumatic technology whose innovations can be traced back not to cities and sanitation but to a source less obvious: the sea. 

Shipworks at Turku, Finland, where some of the world’s largest cruise ships are built and outfitted with MariMatic’s food waste collection system, “Taifun”

Cruise ships are billion-dollar mini-cities that carry thousands of passengers and crew, in addition to all of the food, drink, and other supplies they will consume, and, of course, all the waste those passengers produce. Many of the world’s largest are built in Finland and employ a unique fire prevention system developed by Göran Sundholm, an Elon Musk-type figure who has over a thousand patents to his name and an airplane hangar-sized research-and-development facility he calls “Legoland.” In the 1970s Sundholm developed a system for joining steel pipes so that offshore oil derricks could be assembled underwater without torch welding (thus lessening both risk and costs). Sundholm applied his experience with high-pressure pipelines to develop the first commercially viable application of a system that smothers fires with water vapor instead of streams of water—efficient not just in practice, but in the tight confines of cruise ships.

Sundholm bought a manufacturer of vacuum systems used to pipe food waste from industrial processing plants and other high volume kitchens in controlled environments, including cruise ship galleys. Noticing that the infrastructure for pneumatic collection of garbage had not changed in years, Sundholm decided to enter the market by seeking the types of efficiency improvements he’d developed for other kinds of pipelines. He proposed a pipe made of a plastic composite that offers significantly less friction than steel, so that less energy would be required to pull material through it. Plastic can bend slightly to avoid obstacles and can be joined without welding, which makes installation faster and cheaper. Most important, from an energy-use perspective, it takes less air—and therefore less power—to generate a vacuum in a smaller pipe. Since the 1960s the diameter of pneumatic collection pipe has been dictated by the size of the material it carried—collection bags could get stuck in smaller pipes. Sundholm overcame this by devising a mechanical device that shapes full-size bags to fit a pipe the diameter of a dinner plate, almost forty percent smaller than conventional tubes. 

Within a few years several MariMatic systems will begin operating, including what will be the world’s largest: a 900-ton-per-day facility capable of handling all the refuse generated by the 1.5 million pilgrims who visit the Masjid Al-Haram, or Grand Mosque, in Mecca during the annual haj. 

Rendering of Marimatic’s planned project in Mecca

For now the only way to see their equipment is to visit Sundholm’s Legoland or a recent installation on the outskirts of Tampere, Finland’s third-largest city. Simo Isoaho, the former director of the regional waste management authority, proposed a pneumatic system for a subdivision in Vuores after seeing one in Sweden. As a chemical engineering professor and longtime local politician, he was uniquely qualified to convince fellow decision makers to consider the strategy and to assess the technical qualifications of MariMatic’s technology (which at that point existed only at Legoland). MariMatic’s proposal, which provided the greatest energy efficiency and lowest cost, was selected over that of its two competitors. Vuores’s system currently consumes 45 kwh of electricity per of material ton collected, which is less than half the electricity typically required by pneumatic systems. 

System inlets for residential use in the new town of Vuores | photo: Benjamin Miller

The terminal in Vuores | photo: Benjamin Miller

Helsinki is in the midst of transforming its industrial waterfront. Three of the city’s current urban renewal projects include pneumatic collection. The first, built with Envac pipes, began operating last year in Kalasatama, a new “smart city” district east of the harbor. MariMatic won the next contract for Kruunuvuorenranta, another new waterfront neighborhood. It is too soon to tell whether these projects will be completed as planned, but the presence of multiple projects and competing technologies implies that planners are already learning from each other. 

The MariMatic story, like that of Finnish design, is a reminder that the some of the most powerful ideas come from outsiders. Proponents of pneumatic collection should be encouraged to know that an inventor from such high-stakes industries as fire safety and oil and gas drilling is taking the strategy to new levels of performance by designing fresh approaches to proven techniques. As the cost of pneumatic networks comes down (and the price of truck collection goes up), the cost of installing pneumatic collection infrastructure should become more competitive. As the demand for pneumatic infrastructure grows, manufacturers will invest more to meet local codes, engineers will learn how to specify it, planners will begin to understand when and where it should be used, and government agencies will recognize its benefits by awarding incentives. Green building organizations will offer LEED points, developers will see a marketing advantage, and on and on in a virtuous cycle of technological and administrative evolution until trash tubes are as common and as widely appreciated as the Marimekko poppy on a canvas bag.