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In the late 1960s, the first Tehran Master Plan (TMP) was envisioned by a constellation of local and foreign experts. The TMP, which has been extensively studied, is usually credited to big-name planner and architect Victor Gruen. Scholars have neglected the contributions of local professionals in shaping the plan. Many depict the TMP as the product of Cold War geopolitics and a scheme directly exported to Tehran to facilitate top-down modernization promoted by the pro-American Shah. This popular narrative flattens the complexity of transnational urbanism and obscures the transformative role performed by locals therein. Through archival studies and conducting interviews with local planners involved in the TMP, this paper aims to discover the complex nexus between national and international actors and unravel how Iranian planners collaborated with foreign counterparts to negotiate Tehran’s urban problems and project the future of the city. This paper argues that Gruen served as a figurehead to validate the formation of the first planning document for Tehran by young local planners who had their own planning agenda. The conclusion argues that the transnationalism of planning practices in Iran grew out of an attempt to institutionalize a modern planning regime compatible with global standards while nurturing local experts.

In der vorliegenden Arbeit wurden unterschiedliche land- und forstwirtschafliche Brennstoffe (Holz, Stroh, Getreideganzpflanzen, Heu, Rapspress-kuchen) und deren Aufbereitungsformen (Häckselgut, Pellets) praxistypisch an einer Kleinfeuerungsanlage (50 kW) untersucht. Weitere Einflussgrößen waren der Wärmeleistungsbereich (30 bis 100 % der Nennwärmeleistung) sowie der Brennstoffwassergehalt. Zielgrößen für die Beurteilung waren die Emissionen von Kohlenstoffmonoxid (CO), Staub, Gesamtkohlenstoff (Gesamt-C) und Stickstoffoxiden (NOx), die Partikelgrößenverteilung des Staubes, die Emissionen von polyzyklischen aromatischen Kohlenwasserstoffen (PAK), chlorhaltigen Schadstoffen (Dioxine und andere) und Schwermetallen sowie der Wirkungsgrad der Feuerungsanlage. Zusätzlich wurden eine Reihe von Qualitätsmerkmalen im Brennstoff und in den Aschen (Nähr- und Schadstoffgehalte, einschließlich Schwermetalle, Chlor, Dioxine, PAK) betrachtet. Unterschiede zwischen den landwirtschaftlichen Brennstoffen und Holz bestanden vor allem bei den Staub- und NOx-Emissionen. Letztere waren mit circa 330 bis 480 mg pro Nm3 (Normkubikmeter bei 13 % Sauerstoffgehalt) beim Halmgut (Stroh, Ganzpflanze, Heu) um den Faktor 2 bis 3 höher als beim Holz. Staub lag mit circa 170 bis 250 mg/Nm3 sogar um etwa das 3- bis 5-fache höher. Der Feinstaub (aerodynamischer Durchmesser, dae < 10 µm) hat mit circa 65 bis 95 % den höchsten Anteil an der gesamten Staubemission; bei Halmgut setzt sich die Feinstaubfraktion sogar größtenteils aus Korngrößen des Submikronbereiches (dae < 1 µm) zusammen. Die Emissionen von polyzyklischen aromatischen Kohlenwasserstoffen sind eng mit den CO- und Gesamt-C-Emissionen korreliert, wobei auch hier die Einjahrespflanzen-Brennstoffe Nachteile gegenüber Holz aufweisen. Die am CO-Ausstoß gemessene Verbrennungsqualität scheint jedoch keine wesentliche Auswirkung auf das Niveau des Ausstoßes von Dioxinen (PCDD/F) zu haben. Dafür ist vor allem der Chlorgehalt im Brennstoff entschei, In the present investigation various forestry and agricultural fuels (wood, straw, whole plant grain, hay, rape seed expeller) in different treatments (chopped, pelleted) were investigated under practical conditions in a small-scale multi-fuel furnace (50 kW). Additionally, power range (30 to 100 % of the nominal power output) and fuel moisture effects were investigated. Target values were the emissions of carbon monoxide (CO), dust, total organic carbon (TOC) and nitrogen oxides (NOx), the size distribution of dust particles, the emission of polycyclic aromatic hydrocarbons (PAH), harmful substances containing chlorine (dioxins and others) and heavy metals, as well as the efficiency of the furnace. Additionally, a number of quality characteristics in fuels and ashes were considered (plant nutrient concentrations and harmful substances such as heavy metals, chlorine, dioxins and PAH). Differences between agricultural crops (herbaceous fuels) and wood were mainly observed for NOx- and dust emissions. The latter ranged between 330 and 480 mg/m3 (at standard flue gas conditions and 13 % oxygen), which is around 2 to 3 times higher than for wood. Dust emissions were approximately 170 to 250 mg/m3 for herbaceous fuels, which is even 3 to 5 times higher than for wood. The fine dust particles (aerodynamic diameter, dae < 10 µm) has the highest share of the total dust in the flue gas (65 to 95 %); with herbaceous fuels, these fine dust emissions are even mainly below the sub micron fraction (dae < 1 µm). The emissions of PAH are closely correlated to CO and TOC emissions. Here the disadvantages of fuels from annual crops compared to wood fuel clearly show. The quality of combustion as shown by the CO-emission level does not seem to have an effect on the output level of dioxins (PCDD/F). This proves that the content of chlorine in the fuel is crucial. The results for the PCDD/F-emission of herbaceous fuels are approximately 17 times higher than for wood fuel, which ranged ar