Life Cycle Assessment of Animal Feeds Prepared from Liquid Food Residues: A Case Study of Rice-Washing Water
- Akifumi Ogino *a,
- Mitsuyoshi Ishidaa,
- Hideyuki Ohmoria,
- Yasuo Tanakaa,
- Takahiro Yamashitaa,
- Hiroshi Yokoyamaa,
- Kenji Tatsugawab,
- Satoru Ijirib and
- Tomoyuki Kawashimaac
- a Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization (NARO), 2 Ikenodai, Tsukuba, Ibaraki 305-0901, Japan
b Shokkyo Co., Ltd., 5-9 Matsukawacho, Minami-ku, Hiroshima 732-0826, Japan
c present address: Japan International Research Center for Agricultural Sciences (JIRCAS), 1-1 Ohwashi, Tsukuba, Ibaraki 305-8686, Japan. Assigned to Associate Editor Barbara Amon
Life cycle assessment (LCA) was used to compare the greenhouse gas (GHG) emissions and energy consumption of three methods used to produce animal feed from concentrated rice-washing water (CRW) and disposing of the rice-washing water through wastewater treatment. Four scenarios were compared using LCA: (i) producing concentrated liquid feed by centrifugation (CC) of CRW with wastewater treatment and discharge of the supernatant, (ii) producing concentrated liquid feed by heating evaporation (HC) of CRW, (iii) producing dehydrated feed by dehydration (DH) of CRW, and (iv) wastewater treatment and discharge of nonconcentrated rice-washing water (WT). The functional unit (FU) was defined as 1 metric ton of rice washed for cooking or processing. Our results suggested that the energy consumptions of CC, HC, DH, and WT were 108, 322, 739, and 242 MJ per FU, respectively, and the amounts of GHG emissions from CC, HC, DH, and WT were 6.4, 15.8, 45.5, and 22.5 kg of CO2 equivalents per FU, respectively. When the produced feed prepared from CRW was assumed to be transported 200 km to farms, CC and HC still emitted smaller GHGs than the other scenarios, and CC consumed the smallest amount of energy among the scenarios. The present study indicates that liquid feed production from CRW by centrifugation has a remarkably reduced environmental impact compared with the wastewater treatment and discharge of rice-washing water.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2012. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.