Design for environment applied to rice production

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1 Design for environment applied to rice production Leda Coltro 1*, Luiz Fernando M. Marton 2, Fábio Panciera Pilecco 2, Ademar Cadore Pilecco 2, Lucas Felini Mattei 2 1 Institute of Food Technology ITAL, Packaging Technology Center CETEA, Campinas, SP, Brazil 2 Pilecco Nobre Alimentos Ltda., Alegrete, RS, Brazil Corresponding author. ledacolt@ital.sp.gov.br ABSTRACT Life cycle thinking was applied to the rice production system in order to evaluate the possibilities of environmental impact reduction. Improvements have been applied to several stages of the life cycle as follow: 1) Irrigation, 2) Drying, 3) Core and clean stage, 4) Packaging and 5) Transport. The work was carried out from June 2012 to August The functional unity adopted was 1,000 kg of packed rice (5 kg packs), available at retail. The system boundary considered the field operation, including transportation after harvest, fertilizer production, packaging and transport until the retail. The results have shown the new rice production system has significant environmental performance improvement, mainly water (approx. 200,000 L/t) and energy consumption (approx MJ/t) as well as GHG emission (approx.. 30 kg CO2 eq/t) and yield (1,152 kg/ha), being the new irrigation system responsible for the majority of the benefits. Keywords: rice, irrigation, environmental performance, design for environment, life cycle thinking 1. Introduction Rice cropping fields are important contributor to climate change since they are a major methane source. The area of rice cropping fields in the world is gradually increasing and this area is expected to continue expanding as the world population increases. So, mitigating methane emission in these areas is an important issue. This can be accomplished through water management practices. According to study developed in central Japan by Kudo et al (2014), a compound treatment with a combination of flooding, midseason drainage and intermittent drainage may be an effective water management practice for mitigating greenhouse gas emission and maintaining rice yield. Study developed by Perret et al (2013) on rice production in the North-eastern Thailand in 2010 evaluated 45 diverse rice cropping systems according to three systems, namely wet-season rain-fed, wet-season irrigation, and dry-season irrigation systems. According to the authors, a wide-ranging performances and impacts were observed, despite cropping practices were relatively homogeneous. The differences among the systems were originated mostly from differences in yield, which were largely impacted by water supply. The results showed the low performances and high impacts of dry-season irrigated systems, since they require mostly blue water, while the two other systems rely primarily on green water. Besides, the dry-season irrigated systems require more energy, labor, fertilizers, pesticides, and ultimately yield lower production. Khoshnevisan et al (2014) applied LCA to evaluate the environmental impact of consolidated rice farms (CF) farms that have been integrated to increase the mechanization index, and traditional farms (TF) small farms with lower mechanization index, in Guilan Province, Iran. The results have shown that the energy ratios for CFs and TFs were 1.6 and 0.9, respectively. The two main reasons for the higher energy ratio by the CFs are the total input energy in the CFs was less than that of the TFs and the CFs employed better agricultural management, including the use of higher-yielding varieties of rice that generated higher yields. Then, the results showed that CFs produced fewer environmental burdens per ton of produced rice. The same conclusion was reached for landbased functional unity, which indicates that the differences between the two types of farms were not caused by a difference in their production level, but rather by improved management on the CFs. The study also showed that electricity accounted for the greatest share of the impact for both types of farms, followed by P-based and N-based chemical fertilizers. The LCA results indicated that the use of more mechanical power and an associated increase in the mechanization index will lead to better environmental performance rather than increased environmental burdens from rice cultivation. Besides, the cultivation of higher yielding rice varieties and the use of agricultural inputs according to crop requirements and soil analyses can improve the environmental performance as well. Rice straw can cause environmental impacts if burned in situ in the field. Then, Silatertruksa and Gheewala (2013) conducted life cycle assessment of four rice straw utilization systems, which are (1) direct combustion for electricity, (2) biochemical conversion to bio-ethanol and biogas, (3) thermo-chemical conversion to bio-dme, and (4) incorporation into the soil as fertilizer, in order to compare their environmental performances. According

2 to the authors, the bio-ethanol pathway resulted in the highest environmental performance in relation to reductions in global warming and resource depletion potentials. Rice straw bio-dme was preferable in relation to reduction in acidification potential. Rice straw electricity and fertilizer brought several environmental benefits. However, removal of agricultural residues must be managed carefully since excessive residue removal can degrade the longterm productive capacity of soil resources. Rice (160.3 g/day) and beans (182.9 g/day) are the basis of Brazilians food consumption (IBGE, 2011), that is why rice has been chosen as one of the 18 products of the project End-to-End Sustainability developed by Walmart Brasil and its main suppliers (Walmart, 2013). In this project, Pilecco Nobre Alimentos Ltda. implemented several improvements in the rice production with the aim of reducing the environmental impact of the product with the assistance of CETEA/ITAL. Life cycle thinking was applied to the rice production system in order to evaluate of possibilities of reducing the environmental impact of the rice production. 2. Methods This work was conducted in accordance with the International Standard ISO/TR (ISO/TR 14062, 2002). Taking into account the life cycle thinking, improvements have been applied to several stages of the life cycle of rice production as shown in Table 1. The goal of this work was to reduce the environmental impact of rice production. Traditional rice production system was established as a baseline case against which the impacts of the conditions could be quantified. Table 1. Life cycle stages and respective improvements applied to the rice production. Life cycle stage Traditional production system (baseline) New production system Irrigation Irrigated rice cropping system Underground drip irrigation rice cropping system Drying Firewood furnace and temperature rate system with high grains breakage Steam radiators and homogeneous temperature system with reduced grains breakage Core and clean Without rice recovery Rice recovery after straw removal Packaging Plastic packaging from non-renewable resource Plastic packaging from renewable resource, sugar cane Transport Conventional diesel truck fleet Diesel S10 and more efficient truck fleet The work was carried out from June 2012 to August The new irrigation system was implemented by Pilecco Nobre Alimentos Ltda. in a cultivation area of 64 hectares, in Alegrete, Rio Grande do Sul, Brazil. The functional unity adopted was 1,000 kg of packed rice (5 kg packs), available at retail. The system boundary considered the field operation, including transportation after harvest, fertilizer production, packaging and transport until the retail (Figure 1). Only the steps that have been improved were taken into account. The emissions from fertilization and methane emission from rice fields were calculated using IPCC models (IPCC, 2006). System boundaries Energy Production Fertilizers Production Rice Cultivation Rice Processing T Rice at retail Packaging T = Transport Figure 1. System boundaries adopted in this work.

3 Farm specific data along with industrial production data have been combined in order to model a rice production system. GHG emission factors for transport and energy production were obtained from GHG Protocol Brasil (2012). The environmental aspects relative to the fertilizers production were taken from recognized database and included in the boundary. The inventory quantities fossil/renewable primary energy demand (PED), land use and water use were analyzed. GWP (100 years), eutrophication (EU) and acidification (AP) were estimated according to the CML method (GUINÉE, 2002). 3. Results The improvements applied to rice cultivation, processing and transport are described below as well as the gains of these changes to the environmental impact of the product Irrigation The rice cropping system used in the traditional production system baseline case (Figure 2a) employs continuous irrigated field, which needs a pumping system with a high flow demand since this process is based on water drainage from the pumping point to all the crop area. Due to the high extension of the irrigated area, this takes several days to complete irrigation. Besides, in this process occurs a great water loss due to evaporation and shifting in the channels, as well as contamination of the catchment rivers by fertilizers and pesticides. (a) (b) Figure 2. Irrigation of rice cropping system moved from: (a) Irrigated system to (b) Underground drip irrigation system. The substitution of the irrigated system by the underground cropping system (Figure 2b) allows absorption of the water directly by the radicular system of the plant avoiding water loss by evaporation and shifting since it is based on a system of channels that directs the water flow always to the same place. Besides, the underground cropping system allows all fertilizers and pesticides be applied without loss. The installed pumping power of the underground drip irrigation system is significantly lower than the irrigated system due to the higher water flow in the canalizations. As a result, the underground drip irrigation system has lower energy and water use than the irrigated system, besides lower aquatic eutrophication and ecotoxicity Drying The rice drying process consists of reducing the humidity of the rice grain, still with straw, to values of approx. 10% in order to avoid fermentation and pest propagation (worm, moth, caterpillar). The traditional processes use dryers with furnaces feed by rice straw or firewood to generate hot gases, which gradually remove the humidity from the rice grain. If this process is not well controlled it can degrade the grain by breakage due to formation of temperature gradient. The breakage of the rice grain can also occurs due to the high recirculation the traditional dryers require in order to get high productivity. Broken grains are not used as quality rice.

4 So, in the second semester of 2012 a drying system that uses vapor from thermal power plant feed by rice straw instead of firewood was installed - GEEA project - Alegrete Electric Energy Producer Ltd.. Besides elimination of the firewood, this new system has a differentiated system of drying rack that allows a more homogeneous distribution of the hot air avoiding the breakage of the grains due to temperature gradient, as shown in Figure 3. Since this drying system is more efficient than the traditional one, it reduces the recirculation of grains inside the equipment, which decreases the breakage by moving. (a) Grain Flow (b) Hot Air In Saturated Air Out Air Flow in the Drying Rack Uniform Grains Output Figure 3. Drying systems: (a) traditional drying rack, (b) new system of drying rack. The benefits of this improvement are the use of renewable energy from waste as well as a better yield of whole rice grains Core and clean All rice straw generated by Pilecco Nobre is sent to GEEA - Alegrete Electric Energy Producer Ltd., where it is used as raw material to produce electric energy and silica. However, a fraction of rice without straw as well as rice still with straw is lost during the straw removal process, being forwarded with the straw itself to electric energy generation. The new rice production system has a rice recovery from straw (Figure 4) which works by weight difference between the straw and the grain. This improvement allowed to recover the rice that used to be burnt with the straw and then increased the yield of the productive system. Figure 4. Equipment for rice recovery after straw removal Packaging The packaging of the rice was changed from polyethylene from non-renewable resource to polyethylene from renewable resource (ethanol from sugar cane). The polyethylene from renewable resource has the same properties,

5 performance and versatility of applications as the polyethylene from non-renewable resource, which makes easy its use. For the same reason it is recyclable in the same recycling chain of the traditional polyethylene. The benefits of this improvement are the use of renewable resources and reduction of non-renewable resources consumption (oil), as well as decrease of GHG emissions Transport The transport of rice used to be in a truck fleet based on traditional diesel consumption, which emits 500 mg of sulfur per liter of diesel and has an average fuel consumption of 0.33 L of diesel per km. The improvement of this life cycle stage was based on the substitution of seven trucks by new trucks that uses diesel S10 which emits 10 mg of sulfur per liter of diesel, besides an average fuel consumption of 0.29 L of diesel per km. The benefits of this improvement are reduction of non-renewable resources consumption (oil), as well as lower GHG emissions and acidification potential than the previous fleet. Table 2 summarizes the relative reduction of the environmental impacts considered in this work, taking into account all the improvements made in the rice production system, while Figure 5 shows the contribution of each improvement. Table 2. Improvement of the environmental performance of the rice production system evaluated: Traditional vs New production system. (Functional unity = 1,000 kg of packed rice). Parameter Improvement Yield (kg/ha) 1, Primary energy demand (MJ) Electric energy consumption (MJ) Non-renewable energy (MJ) Water consumption (L) -198, Non-renewable resources (kg) Firewood consumption (kg) Rice waste (kg) Land use (ha) GWP (100yr) (kg CO 2 eq) Aquatic eutrophication (kg PO 4 ---eq) Aquatic acidification (kg SO 2 eq)

6 Figure 5. Contribution analysis of the improvements made in the rice production system to the impact categories evaluated. 4. Discussion The combined modifications clearly produced substantial benefits for the environmental performance of rice production, mainly reduction of water, energy and firewood consumption as well as GWP and aquatic acidification. The key opportunity in terms of environmental benefit is the reduction of water consumption (approx. 200,000 L/t of rice) which is quite relevant due to the water scarcity we are facing nowadays because of the climate change. According to the last IPCC report (2014), the already observed and the projections of climate change for the South America will compromise the water availability for this region and direct impacts should occur in the domestic and industrial water supply as well as in sectors strongly water dependent as hydroelectricity production and agriculture. Besides, the yield increased by 15%, which means less land use for cultivation, reduction of inputs (fertilizers, pesticides etc.) and associated emissions, besides feeding more people. The new irrigation system was responsible for the majority of the environmental impact reductions, i.e. electric energy and water consumption, land use, yield, aquatic eutrophication and acidification. Besides, this improvement contributed also to reduce the non-renewable resources consumption and GHG emissions. The new drying system contributed to the reduction of firewood consumption, while the improvement made in the core and clean stage reduced the rice waste. The change in the packaging material contributed to reduce the non-renewable resources and non-renewable energy use as well as GHG emissions. The modification made in the transport stage contributed to reduce the same burdens than the new packaging, but with lower reduction of the non-renewable resources and non-renewable energy use. 5. Conclusion Aquatic acidification (kg SO2 eq) Aquatic eutrophication (kg PO4---eq) Yield (kg/ha) GWP (100yr) (kg CO2 eq) Land use (ha) Rice waste (kg) Firewood consumption (kg) Non-renewable resources (kg) Water consumption (L) Non-renewable energy (MJ) Electric energy consumption (MJ) Primary energy demand (MJ) 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Irrigation Drying Core and clean Packaging Transport This work supplied important results for the better environmental performance of the rice production, making this product a lower environmental impact than the traditionally cultivated rice.

7 An expressive reduction of water consumption was observed in the rice cultivation due to the substitution of the irrigated rice cropping system by the underground drip irrigation rice cropping system, besides other benefits like reduction of energy use, fertilizer and pesticide loss and GHG emissions. The 15% increased yield was mainly a result of the new cultivation system. Acknowledgement The authors are grateful to Pilecco Nobre Alimentos Ltda. for the financial support. The authors also thank all the people who have contributed to this study or by responding the questionnaires or for their useful comments during the development of this project. 6. References GHG Protocol Brasil (2012) Especificações do programa brasileiro GHG protocol. 1a ed., 76p. Guinée JB (2002) Handbook on LCA: Operational guidelines to the ISO Standards. Netherlands. IBGE (2011) Pesquisa de orçamentos familiars : Análise do consume alimentar pessoal no Brasil. IBGE: Coordenação de Trabalho e Rendimento. Rio de Janeiro: IBGE, 150p. IPCC (2006) 2006 IPCC Guidelines for National Greenhouse Gas Inventories. Prepared by the National Greenhouse Gas Inventories Programme. Eggleston, H.S. Buendia, L., Miwa, K., Ngara, T., Tanabe, K. (Eds.). IGES. Japan. IPCC (2014) Climate Change 2014: Impacts, Adaptation, and Vulnerability. Prepared by the National Greenhouse Gas Inventories Programme. Christopher Field, Vicente Barros, Katharine Mach, Michael Mastrandrea (Eds.). WGII AR5. INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ISO (2002) ISO/TR 14062: environmental management: integrating environmental aspects into product design and development. Genève. 24p. Khoshnevisan B, Rajaeifar MA, Clark C, Shamahirband S, Anuar NB, Shuib NLM, Gani A (2014) Evaluation of traditional and consolidated rice farms in Guilan Province, Iran, using life cycle assessment and fuzzy modeling. Science of the Total Environment 481: Kudo Y, Noborio K, Shimoozono N, Kurihara R (2014) The effective water management practice for mitigating greenhouse gas emissions and maintaining rice yield in central Japan. Agriculture, Ecosystems and Environment 186:77 85 Perret SR, Thanawong K, Basset-Mens C, Mungkung R (2013) The environmental impacts of lowland paddy rice: A case study comparison between rainfed and irrigated rice in Thailand. Cash Agric. 22: Silatertruksa T, Gheewala SH. (2013) A comparative LCA of rice straw utilization for fuels and fertilizer in Thailand. Bioresource Technology 150: Walmart, End-to-End Sustainability (Publication in Portuguese) 3 rd ed p. Available in: