Material and energy flow analysis of the Malawian tea industry

Abstract

This paper briefly reviews the material and energy flows of the Malawian tea industry, in order to identify opportunities and reduce its environmental impacts. The review also details the concept and methodology as well as studies on applications of material and energy flow analysis. Environmental impacts are calculated with a life cycle assessment approach, using CML methodology. Results indicate that green leaf consumption in the studied factories ranged from 4.19 to 6.33 kg green leaf/kg made tea (MT), with an average of 4.96 kg per kg of made tea compared to 4.5 and 4.66 kg green leaf for tea factories in Kenya and Sri Lanka, respectively. Average wood consumption in Malawian tea factories is 3.35 kg/kg made tea and specific water consumption ranged from 1.92 to 8.32 kg/kg MT. In addition, the average value of greenhouse gas (GHG) emissions for eight factories is 4.32 kg of CO2-eq/kg MT as compared to 2.27 and 2.7 kg CO2-eq/kg in similar factories in Kenya and Sri Lanka, respectively. The major sources emitting GHG are from boiler fuel combustion and stand-by diesel power generation system. The study indicates that global warming has the highest environmental impact (88%), followed by acidification (6%) and eutrophication (2%), whereas human toxicity is lowest (<1%). The findings demonstrate how MEFA provides early recognition of environmental problems and how it can be used to establish priorities for improving operations in the existing factories.

Sustainable scenarios for alkaline protein extraction from leafy biomass using green tea residue as a model material

“…The LCA results are quantified in detail for the most relevant impact categories for China and tea production, i.e. climate change, ozone depletion, terrestrial acidification, eutrophication, photochemical oxidant formation, particulate matter formation, water depletion, natural land transformation, and fossil depletion.…”

“…Little is published on the environmental impacts of tea cultivation and processing . The CO 2 equivalent emissions for tea cultivation and harvesting under Kenyan conditions are estimated around 0.111–0.133 kg CO 2 equivalent/kg fresh tea leaves .…”

Integrated Material Flow Analysis and Process Modeling to Increase Energy and Water Efficiency of Industrial Cooling Water Systems

“…MFA is based on the mass‐balance principle derived from the law of mass/energy conservation, which states that mass and energy are neither created nor destroyed by physical processes. Therefore, material inputs must equal material outputs plus changes in stocks for every process (Ayres ; Taulo and Sebitosi ). MFA encompasses a variety of analytical approaches (OECD ) and is widely applied in different fields, including industrial ecology, resource management, waste management, and environmental management (Allesch and Brunner ; Bai et al.…”

Environmental sustainability and financial performance of the small‐scale tea processors in Kenya

“…For example, 1 kg of made tea is estimated to cause between 2.51 and 5.41 kg of CO 2 equivalent emissions and consumes between 0.42 and 1.08 kWh of electricity. The resulting environmental impact include global warming (88%), acidification (6%), eutrophication (2%), and human toxicity of about 1% (Taulo & Sebitosi, ). The tea processors struggle to promote environmentally friendly practices to minimize their ecological footprint.…”

“…The resulting environmental impact include global warming (88%), acidification (6%), eutrophication (2%), and human toxicity of about 1% (Taulo & Sebitosi, 2016). The tea processors struggle to promote environmentally friendly practices to minimize their ecological footprint.…”