Clean Technol., ol. 23, No. 4, December 2017, pp. 388-392 청정부품 / 제품설계 통기성필름제조공정의전과정평가 안중우 * 성신여자대학교청정융합과학과서울특별시강북구도봉로 76 가길 55 ( 미아동 ) (2017 년 3 월 8 일접수 ; 2017 년 7 월 24 일수정본접수 ; 2017 년 7 월 24 일채택 ) Life Cycle Assessment on Process of Breathable Film Production Joong Woo Ahn* Department of Interdisciplinary Eco Science, Sungshin Women's University 55 Dobong-ro 76ga-gil, Gangbuk-gu, Seoul, 142-732, Korea (Received for review March 8, 2017; Revision received July 24, 2017; Accepted July 24, 2017) 요 약 본연구에서는통기성필름의제조공정에대한환경영향특성을분석하기위해전과정평가를수행하였다. 특성화와정규화결과, 영향범주별환경영향은지구온난화가약 97%. 인간독성 2% 의기여도를나타났다. 주요기여도는투입물인고밀도폴리에틸렌 (HDPE) 과폴리프로필렌 (PP) 그리고에너지인전력으로나타났다. 세부공정에서는혼합단계 (Mixing) 가 57%, 부착단계 (Lamination) 29% 압출단계 (Extruder) 10% 순으로높은환경영향기여도를보였다. 환경영향을개선하기위해서는전력사용량을감소시키거나원재료인 HDPE 나 PP 를제외한수율향상을고려한새로운공정시스템설계가필요하다. 주제어 : 통기성필름, 전과정평가, 환경영향 Abstract : In this study, a quantitative environmental impact assessment for the production process of breathable film was conducted employing Life Cycle Assessment (LCA) methodology. Among the various categories, Global Warming (GW) accounted for the highest impact (97%) followed by Human Toxicity (HT). And the key substances of various impact categories included HDPE, PP, and electricity. In the production process, the high impact resulted from mixing process (57%), lamination process (29%), and extruder process (10%). To improve environmental impact, it is necessary to design a new process system that reduces the amount of electricity used and that increases production yields, if raw materials such as HDPE and PP owe excluded. Keywords : Breathable film, Life cycle assessment, Environmental impact 1. 서론 통기성필름은기체및수증기는투과하나액체등은투과할수없는연속된기공이필름내부에분포되어있는구조를가지고있는기능성필름으로유아용기저귀, 일회용방한, 방수등의위생용품에사용되고있다. 이러한통기성필름의제조방법중연신법 Choi [1] 을이용한통기성필름은폴리에틸렌과무기물이균일하게혼합되어만들어진펠렛 (pellet) 을압출과연신등의공정으로내부의기공이연속적이며균일하게형성된다. 후속공정인라미네이팅 (Laminating) 공정 Kim and Kim [2] 은통기성필름과다른소재를복합하는공정으로기저귀의경우통기성필름과부직포를복합한제품이개발되고있다. 이러한공정으로제조되는통기성필름의투입원료및에너지와배출되는물질을분석하여기술적환경가치를파악하는것은확대되고있는통기성필름시장에서고려해야될사항이다. 본연구는통기성필름제조공정의전과정평가 (Life Cycle Assessment) 를통한환경성평가를세부공정단계로구별하여주요공정과기여물질을규명하고한다. * To whom correspondence should be addressed. E-mail: jwahn@sungshin.ac.kr; Tel: +82-2-920-7897; Fax: +82-2-920-2786 doi: 10.7464/ksct.2017.23.4.388 pissn 1598-9712 eissn 2288-0690 This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licences/ by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 388
통기성필름제조공정의전과정평가 389 2. 통기성필름의전과정평가 2.1. 목적정의통기성필름의제조공정각단계에서발생되는환경부하를분석하여정량적인환경영향을평가하며, 영향범주별주요영향물질과공정을규명하여보다환경친화적제품생산을위한개선방안을찾고자한다. 2.2. 범위정의 2.2.1. 기능및기능단위, 기준흐름통기성필름의기능은공기통풍성과방수기능을요구하는일회용위생제품의소재로, 기능단위와기준흐름은 Table 1과같이동일하게정의하였다. 2.2.2. 시스템경계본연구의시스템경계는원료인폴리에틸렌과탄산칼슘을혼합하여고분자압출기를통해성형된필름에통기성을형성후완제품까지의공정단계로 Gate to Gate로정의하였다. 2.2.3. 데이터범주데이터범주는원료물질, 보조물질, 용수, 에너지, 제품, 부산물, 대기및수계배출물, 고형폐기물로구분하였다. 2.2.4. 데이터품질요건본연구의데이터는현장데이터와국가및해외 LCI 데이터로구분되며, 시간적경계는지난 1년공정별로수집한업체의현장데이터이며, 상위및하위공정의연결은국가및해외 LCI 데이터를사용하였다. 지역적경계는수송공정의제외로해당지역데이터를국내 LCI 데이터와동일하게설정하였다 (Table 2). 랩 (wrap) 은고밀도폴리에틸렌 (HDPE), 부직포 (non-woven fabrics) 와라벨 (label) 은폴리프로필렌 (PP), 잉크 (ink) 와용매 (solvent) 는유기화학물질 (chemicals organic), 폐유기용제 (organic solvents) 와휘발성유기물 (volatile organic compounds) 은유해폐기물 (hazardous waste) 의 LCI DB를적용하였다. 2.3. 전과정목록분석 2.3.1. 공정흐름도폴리에틸렌 (PE) 과탄산칼슘 (CaCo 3) 을원료로하는통기성필름의제조공정은 Figure 1과같다. 제조공정별환경부하값과원인규명을위해실제제조단계에맞춰총 8개의단위공정인혼합 (Mixing), 압출 (Extruding), 냉각 (Cooling), 연신 (Extender), 프린팅 (Printing Dry), 부착 (Lamination), 절취 (Slitting), 포장 (Wrapping) 으로구별하였다. 혼합단계에서는폴리에틸렌 (HDPE) 과탄산칼슘 (CaCo 3) 을교반기를통해혼합하는공정이며압출단계에서다이스를통해필름으로성형후냉각단계에서성형된필름을결정시키게된다. 연신단계에서는통기성을형성하며프린팅단계에서는프린팅후잉크를필름에정착시키게된다. 부착단계는통기성필름과부직포에열을가하여접착시킨후절단단계에서제품을절취한후포장단계를거쳐통기성필름이제조된다. 2.3.2. 데이터수집및계산데이터수집은업체의현장데이터를공정별로수집하였으며, 상위및하위흐름의연결은환경부와산업통상자원부에서구축한국내 LCI 데이터베이스 [3] 를적용하였다. 해외 LCI 데이터베이스는 Ecoinvent Kim et al. [4] 에서구축한데이터베이스를사용하였다 (Table 3). 2.2.5. 가정및제한사항 투입물질중 PE 수지 (polyethylene), 포장지 (wrapping paper), Table 1. Scope definition Function Functional unit Reference flow Breathable films used in the manufacture of disposable sanitary products Amount of breathable film 1 kg 1 kg of breathable film Table 2. Data quality Group Temporal Regional Technological Up/Down stream Most recent data Transport stage Production stage - 2015 Annual data Local data - Local data - - Technologies of the target company Figure 1. Process flow diagram for breathable film.
390 안중우 Table 3. Data sources for LCI Group Material Data category Input Energy Output HDPE (High-Density Polyethylene) Main material Data source Survey Calculation Estimation Remark It replaced the polyethylene, wrapping paper, wrap CaCO 3 Main material - RPP (Random Polypropylene) Sub-materials It replaced the non-woven fabrics, label Recycled paper Sub-materials It replaced the paper core, pad Chemicals organic Sub-materials It replaced the ink, solvent Electricity - - Heating oil - - Process oil - - Breathable film Product - Waste HDPE Recycling - Waste oil Recycling - Hazardous waste Incineration It replaced the organic solvents, nolatile organic compounds 2.4. 전과정영향평가전과정영향평가는산업통상자원부 ( 구지식경제부 ) 의영향평가방법론과특성화 (Characterization) 및정규화 (Normalization) 인자를적용하여 Phae et al. [5] 분류화, 특성화, 정규화단계로수행하였으며, 영향범주는오존층파괴 (Ozone Layer depletion, OD), 산성화 (Acidification, AD), 자원고갈 (Abiotic resource depletion, ARD), 지구온난화 (Global warming, GW), 부영양화 (Eutrophication, EUT), 광화학산화물생성 (Photochemical oxidation creation, POC), 인간독성 (Human toxicity, HT), 생태독성 (Ecotoxicity, ET) 총 8개범주를고려하였다. 2.4.1. 특성화결과 통기성필름 1 kg 제조를기준으로계산된특성화값은 Figure 2 및 Table 4와같다. 영향범주주요물질은오존층파 Figure 2. Environmental impact of materials in process of breathable film production. Table 4. Results of characterization Impact category OD AD ARD GW EUT POC HT ET Unit kg CFC11 kg SO 2 1/yr kg CO 2 3- kg PO 4 kg C 2H 4 kg 1,4 DCB kg 1,4 DCB HDPE 1.64.E-08 1.18.E-03 2.11.E-02 1.09.E+00 1.26.E-03 1.33.E-03 1.90.E-02 1.77.E+00 CaCO 3 2.70.E-10 1.32.E-05 1.73.E-05 4.27.E-03 2.17.E-06 2.11.E-07 3.63.E-04 1.24.E+00 Input RPP 1.15.E-08 8.20.E-04 1.06.E-02 4.39.E-01 1.93.E-04 7.44.E-04 1.59.E-02 8.47.E-01 Re-Paper 1.12.E-08 1.77.E-04 3.19.E-04 4.87.E-02 2.96.E-05 5.41.E-06 1.17.E-02 8.81.E-01 Chem-organic 5.79.E-08 2.22.E-04 6.57.E-04 6.60.E-02 3.46.E-05 2.50.E-05 4.89.E-02 9.74.E+00 Waste HDPE -2.84.E-09-1.07.E-04-3.55.E-03-1.54.E-01-2.01.E-04-2.32.E-04-3.11.E-03-2.70.E-01 Output Waste oil 1.56.E-14 1.86.E-07 1.08.E-06 1.63.E-04 1.35.E-08 3.29.E-09 7.98.E-07 8.55.E-03 Hazardous waste 5.50.E-11 4.30.E-05 3.65.E-05 1.09.E-02 5.33.E-06 9.80.E-08 5.55.E-02 4.39.E+00 Electricity 2.14.E-10 5.19.E-04 1.07.E-03 3.08.E-01 9.68.E-05 2.29.E-05 9.64.E-04 1.39.E-01 Energy Heating oil 1.93.E-09 6.51.E-07 1.24.E-05 2.40.E-04 1.67.E-07 8.24.E-08 1.90.E-04 1.03.E-01 Process oil 4.10.E-11 1.50.E-07 1.13.E-06 1.40.E-05 1.45.E-08 6.25.E-09 5.82.E-05 1.67.E-03
통기성필름제조공정의전과정평가 391 괴범주에서는프린팅단계에투입되는잉크와용제 (Chemicals organic) 가 57%, 주원료인고밀도폴리에틸렌 (HDPE) 16%, 부직포와라벨 (RPP) 이 11%, 페이퍼코어와패드에사용된 Recycled paper가 11% 로나타났다. 산성화범주에서는 HDPE 38%, RPP 27%, 전력이 17% 로나타났으며지구온난화범주도 HDPE 51%, RPP 21%, 전력이 15% 의기여도를보였다. 자원고갈의경우 HDPE 56%, RPP 28%, 전력 3% 와부영양화범주에서 HDPE 69%, RPP 11%. 전력 5%, 광화학산화물생성범주에서 HDPE 56%, RPP 32%, 전력 1% 로산성화와지구온난화범주에비해전력의기여도가낮았다. 그밖에인간독성범주에서는소각되는유기용제와휘발성유기화합물 (hazardous waste) 이 36%, 잉크및용제 31%, HDPE 12%, 생태독성범주에서도유기용제와휘발성유기화합물이 50%, 잉크및용제 23%, HDPE가 9% 의기여도를보였다. 2.4.2. 정규화결과통기성필름 1 kg 제조공정에대한정규화결과는 Table 5와같으며, 전체공정에대한영향범주별기여도는지구온난화가 97% 로주요영향범주로나타났으며다음으로인간독성이 2% 로나타났다. 단위공정별기여도는 Figure 3과같이원료혼합단계 (Mixing) 가 57%, 통기성필름을맞붙이는부착단계 (Lamination) 가 29%, 필름에통기성을형성하는압출단 계 (Extruder) 가 10%, 잉크를필름에정착시키는프린팅단계 (Printing Dry) 가 5% 의순으로나타났다. 각공정의물질별기여도는혼합단계에서는원료인 HDPE가 70%, 부착단계에서는부직포로사용된폴리프로필렌 (RPP) 이 81%, 압출단계에서는전력이 99%, 프린팅단계에서는잉크와용제가 69% 으로나타났다. 다시재활용되는합성수지와포장지는압출단계와부착단계에서미미한환경부하삭감효과 (Avoided Impact) 를보였으나절취단계 (Slitting) 에서환경부하삭감효과가음 (-) 의값으로나타났다. 4. 결론본연구에서는통기성필름제조공정의환경부하량을전과정평가를적용하여정량화했으며 8가지영향범주에대하여분석하였다. 특정영향범주에대한투입물및배출물의상대적기여도를보기위해특성화단계를실시했으며, 산성화, 지구온난화, 자원고갈, 부영양화, 광화학산화물생성범주에서고밀도폴리에틸렌 (HDPE) 와폴리프로필렌 (PP) 그리고전력순서로높은기여도를보였다. 인간독성과생태독성범주에서는유기용제와휘발성유기화합물과잉크및용제가주요물질로나타났으며오존층파괴범주에서는잉크와용제및 HDPE로규명되었다. 정규화를통해영향범주별로비교한결과, 지구온난화가 97% 로주요영향범주로나타났으며단위공정별기여도는혼합단계 (Mixing) 가 57%, 부착단계 (Lamination) 29%, 압출단계 (Extruder) 10%, 프린팅단계 (Printing Dry) 가 5% 로나타났다. 통기성필름의제조공정에서환경부하감소를고려한다면환경영향력이큰주요물질의함량을줄이거나환경영향이적은물질로대체할수있는방법을도출하는것이이상적인방법 Lim [6] 이지만폴리에틸렌이나폴리프로필렌처럼투입되는원재료에의한환경부하가월등히높은경우그다음환경영향인자로규명된전력량의감소와통기성필름의공정별수율을향상시킬수있는공정시스템설계가환경영향을저감하는방안이될수있을것으로판단된다. 감사 Figure 3. Normalization result of process for breathable film production. 이논문은성신여자대학교 2016년도성신여자대학교학술연구조성비지원에의하여연구되었음 Table 5. Normalization result of process forbreathable film Mixing Extruder Extender Printing Dry Lamination Slitting Re-winding Wrapping OD 6.69.E-10 4.44.E-12 8.37.E-11 2.36.E-09 5.79.E-10-1.09.E-10 3.12.E-11 4.26.E-10 AD 4.65.E-02 1.28.E-02 1.09.E-04 1.05.E-02 4.04.E-02-1.19.E-03 4.82.E-04 6.91.E-03 ARD 5.16.E-01 1.59.E-02 4.33.E-04 1.73.E-02 3.26.E-01-8.07.E-02 5.45.E-04 1.19.E-02 GW 5.93.E+03 1.05.E+03 4.93.E+00 4.25.E+02 3.01.E+03-5.77.E+02 1.85.E+01 3.00.E+02 EUT 1.62.E-02 7.64.E-04 6.18.E-06 5.23.E-04 3.17.E-03-2.34.E-03 2.66.E-05 4.95.E-04 POC 1.34.E-02 1.26.E-04 1.38.E-06 2.59.E-04 9.46.E-03-2.24.E-03 3.82.E-06 1.71.E-04 HT 2.63.E+01 7.89.E-01 1.18.E+00 1.43.E+02 2.71.E+01-3.90.E+00 1.10.E+00 1.51.E+01 ET 4.86.E+00 1.36.E-01 2.62.E-01 2.30.E+01 1.71.E+00-3.88.E-01 9.85.E-02 1.35.E+00
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