別紙41 (課程博士(英文))Date of submission (month day, yeal、)January lo,2019

Depanment
Environmental
StudentlD Number

D 123430

and Life

SupeTvisoTS
HIROYUKIDAIMON

Sciences

TATSUO OGUCHI

Dunuwila Mudiyansela套e pasan

Pplicant's nameTharuka Dunuwila

Abstract(Doctor)

Integration ofprocess Analysis and Decision・Making Tools f01'
T北le ofThesis

the sustainabiⅡty hnprovements in Raw Rubber Manufacture(天然ゴム製造における持続可能性改善のためのプロセス分析と意思決定ツールの統合)
Approx.80o words

Raw rubber manufacture is an industry mainly based in developing countries inSouth and south East Asia.1t has been a prominent source which brings foreign revenue
to such countries. Reported as material・, energy・, and labor・intensive, this industry has
been confronted with high cost of manufacture, 10w cost efficiency and various
environmentalissues. Therefore, the main aim ofmy research has been addressing theseissues through improving raw rubber manufacture to have less lnaterial and monetary
10sses, envh'onmental and negative socia11mpacts. Manufacturing major raw rubber
Products ofcrepe rubber, concentrated latex, and ribbed smoked sheets in sri Lanka hasbeen subjected to this research.

Firstly, crepe rubber and ribbed smoked sheet manufacture were analyzed using anovel method to reach the aim. This method deployed:1) material aow analysis (MFA),
material aow cost accounting (MFCA) and environmental Hfe cycle assessment(ELCA)
to quantify material ao、Ns and waste, monetary losses, and greenhouses gas (GHG)
emissions,2) pareto and what・ifanalyses,information from aeld inta'views and literature
to develop improvement options; and 3) re・execution of MFA, MFCA and ELCA toforesee the degree of improvement. simple cost benefit analysis was also employed toknow the flnancial feasibility of improvement options.1n terms of crepe rubber
manufacture, water and chemical use found to be the factors affecting monetary losses
Whereas electricity had been a key driver of GHG emissions.＼入7hile monetary losses 、vere
found negli部ble in ribbed smoked sheet manufacture, firewood use had been a InaJor
factor affecting GHG emissions. Based on field interviews and literature, viable

Improvement options were developed; for instance, instalHng water reuse system, re、determining dry rubber content and insta11ing solar panels were proposed for reducing
Water, chemicals and electricity, respectively in crepe rubber manufacture. To reduce
丘rewood use in ribbed smoked sheet manufacture, an efficient smoke house Consulnlng

Iess fire、Nood was proposed.1mprovement options were foreseen to be saving water,
Chemical, energy and firewood to give remarkable financial and environmental benefits

for both manufacturing lines. Meanwhile, the simple cost beneat analysis indicated thataⅡ improvement options were financiaⅡy feasible
Secondly, the previous method was further modified to be applied to concentrated
Iatex manufacture. Discounted cash aow analysis (DCFA) and greenhouse gas payback
time (GPBT) were integrated in this regard for a detailed economic and environmental
feasibility assessment. Nove110ss reduction efflciency (LRE) index was also introduced
to measure overaⅡ efficiency of improvement options. Rubber losses and chemical
Consumption were found to be main factors affecting monetary losses lNhereas electricity
Consumption was identified as a key driver of GHG emissions. similar to previous
research, appHcable improvement options were proposed based on field interviews andIiterature. Extending sedimentation time during the addition of chemicals and insta11ing
trap tank were amongst the improvement options proposed for reducing chemicals andrubber loss, respectively.1nsta11ing inverters and solar panels were proposed t0 10wer
electricity consumption to a11eviate GHG emissions. Results were promising as large

Proportion ofmonetary losses and environmentalimpacts were foreseen to be loW引'ed by
the proposed improvement options. As per DCFA and GPBI, proposed improvement
Options were found to be economicaⅡy and environmentaⅡy feasible. Novel LRE index

Was proven to be effective as it could identi6ed insta11ing trap tank as tl〕e best option ofa11.

Not scrutinizing socialimpacts ofnaturalrubber manufaCれlre 、Nas a major lacuna inboth methods; hence, tl〕irdly, we tried performing a socia11ife cycle assessment (SLCA)
SLCAis arelativelynewdiscipHne andhas no designatedmethod orframeworkpublishedyet.1herefore, a new method based on Analytic Hierarchical process (AHP) wasdeveloped for conducting sLCA. Quantifiability ofnegative and positive socialimpacts,and foreseeability of the improvement in social aspect wa'e the key features of thismethod. This method was used to scrutinize the socialimpact ofworkers at a ra、N rubber
factory in sri Lanka. Results daimed that health and safety, and social benefit/socialSecurity of workers were affected thereby jeopardizino working conditions, and healthand safety ofthe country or area. proposing countermeasures for the identified issues, theextentto which the said aspects can be improved was clarified