Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul 2010 Seasonal Variation on Combustible Set-outs under “Door-to-door” Collection Method with “Pay-as-you-throw” system 1 Shinya Suzuki, Ayako Tachifuji, Yasushi Matsufuji Department of Civil Engineering, Fukuoka University Nanakuma, Johnan-ku, Fukuoka, Japan

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 1-1 Background in Japan 1)Increasing number of municipalities begun “charge” for waste collection - in many cases, “Pay-as-you-throw” system - by using specific waste bag 2) Some municipalities convert way of waste collection - from “station” collection (traditional method in Japan) - to “door-to-door” collection 2) Some municipalities convert way of waste collection - from “station” collection (traditional method in Japan) - to “door-to-door” collection - specify common waste collection point for multiple households - unspecified people dispose of waste carelessly, which makes there dirty - too heavy for elderly people or physically-challenged people to bring waste - specify common waste collection point for multiple households - unspecified people dispose of waste carelessly, which makes there dirty - too heavy for elderly people or physically-challenged people to bring waste - Each household set out waste bag in front of entrance of housing - clarify waste generator’s responsibility, stimulate waste separation - anxiety on increase of cost of waste collection - Each household set out waste bag in front of entrance of housing - clarify waste generator’s responsibility, stimulate waste separation - anxiety on increase of cost of waste collection Specific waste bag - in order to realize waste minimization effectively

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 1-2 Objective In previous our study, - most households decided to use only 1 kind of waste bag - from long time experience - tended to keep from setting out waste bag - for adjustment of amount of waste in bag - additional survey in summer season In previous our study, - most households decided to use only 1 kind of waste bag - from long time experience - tended to keep from setting out waste bag - for adjustment of amount of waste in bag - additional survey in summer season For better management on waste collection, To clarify characteristics on waste set-outs - set-out frequency, - number of waste bag, - capacity of waste bag,- weight of waste bag But, seasonal variation still remained to be clarified - under “door-to-door” collection method - with “pay-as-you-throw” system - under “door-to-door” collection method - with “pay-as-you-throw” system

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 2-1 Solid Waste Management Fukuoka city, Japan One district in “Fukuoka city” was selected for survey of combustible waste - 1,664 peoples- 673 households - 9,800 people/km 2 Typical residential area in Japan. “Fukuoka city”, 8th largest city, 1.4 million people, - for MSW, “pay-as-you-throw” system, since Oct ) Combustibles, 2) Incombustibles, 3) recyclables “Glasses and PET bottles”, 4) Bulky waste Combustibles - average unit amount of waste: 0.6 (kg/person/day) (90% of MSW) - 10% reduction occurred by introducing “pay-as-you-throw” system - Households can buy any capacity they like - collected twice a week in night time under “door-to-door” collection method Combustibles - average unit amount of waste: 0.6 (kg/person/day) (90% of MSW) - 10% reduction occurred by introducing “pay-as-you-throw” system - Households can buy any capacity they like - collected twice a week in night time under “door-to-door” collection method - 15 litters (15 yen/bag), 30 litters (30 yen/bag), 45 litters (45 yen/bag; )

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 2-2 Analytical Methods 50 sample households 50 sample households - with a variety of household size - used specified waste collection point - on Mar. 7 th 2006, Mar. 10 th, Mar. 14 th, Mar. 17 th, continuously in spring - on Aug. 26 th 2008, Aug. 29 th, Sep. 2 nd, Sep. 5 th, continuously in summer - enabled us to confirm retention time in each waste bag In summer season, many households set out “garden waste” with usual combustible waste generated from daily activities, - such households have been excluded from this analysis. In summer season, many households set out “garden waste” with usual combustible waste generated from daily activities, - such households have been excluded from this analysis. Actual measurement survey on amount of waste - to clarify actual status on waste set-outs Actual measurement survey on amount of waste - to clarify actual status on waste set-outs

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-1-1) Actual Status on Waste Set-out Pattern 6 CATEGORIES confirmed for waste set-outs in summer season - more than 2bags? 1 bag? - 45 L? 30 or 15 L? 6 CATEGORIES confirmed for waste set-outs in summer season - more than 2bags? 1 bag? - 45 L? 30 or 15 L? CATEGORY 3) was not confirmed in spring season. - changed capacity of waste bag - to avoid long storage of waste - to keep from bad smell CATEGORY 3) was not confirmed in spring season. - changed capacity of waste bag - to avoid long storage of waste - to keep from bad smell

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-1-2) Difference of Waste Set-out Pattern In summer season, households tended to set out, - more frequently, more than 2 bags, with smaller capacities of waste bag - Percentage of 30 or 15 L of waste bag was much higher In summer season, households tended to set out, - more frequently, more than 2 bags, with smaller capacities of waste bag - Percentage of 30 or 15 L of waste bag was much higher

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-2-1) Unit Amount of Waste in each CATEGORY Distribution of unit amount of waste changed - in some CATEGORIES Distribution of unit amount of waste changed - in some CATEGORIES C-1) 45 L >2 bags C-4) 45 L 1 bag C-2) 2 kinds >2 bags C-5) 2 kinds 1 bag C-6) 30 or 15 L 1 bag C-3) 30 or 15 L >2 bags C-4): 1.0 – 2.0 (kg/household/day) - in spring season 1.0 – 1.5 (kg/household/day) - in summer season C-3): near 1.5 (kg/household/day) - in summer season C-4): 1.0 – 2.0 (kg/household/day) - in spring season 1.0 – 1.5 (kg/household/day) - in summer season C-3): near 1.5 (kg/household/day) - in summer season To clarify relationships between waste set-out pattern and amount of waste, Coverage of each unit amount of waste: - very narrow Coverage of each unit amount of waste: - very narrow

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-2-2) Seasonal Change of Waste Set-outs Capacity: 30 or 15 L Capacity: 45 L More than 2 bags 1 bag Spring Summer VARIABLE ZONE Relationships between number and capacity of waste bag In spring season, -Households who have a large amount of waste: - tend to use larger capacity of waste bag - tend to use 45 L and set out 1 bag every time In spring season, -Households who have a large amount of waste: - tend to use larger capacity of waste bag - tend to use 45 L and set out 1 bag every time In summer season, -Some households changed capacity of waste bag In summer season, -Some households changed capacity of waste bag Variable zone was formed only around border line of more than 2 bags or 1 bag every time Larger amount of waste Smaller amount of waste

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-2-3) Impact on Profile of Waste Set-outs Spring Summer 30 or 15 L >2 kinds 45 L We should take care of annual change of waste amount Seasonal change of waste set- outs occurred only for limited households – 1.5 (kg/household/day) - as stated before – 2.0 (kg/household/day) - set out more than 2 kinds of waste bag Seasonal change of waste set- outs occurred only for limited households – 1.5 (kg/household/day) - as stated before – 2.0 (kg/household/day) - set out more than 2 kinds of waste bag Seasonal change - very small - negligible Seasonal change - very small - negligible

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 3-3-1) Annual change? 30 or 15 L >2 kinds 45 L C-4)C-2)C-3) Amount of waste still continued to decrease gradually - distribution of unit amount of waste will change year after year - drastic change of waste set-outs will occur in near future? Amount of waste still continued to decrease gradually - distribution of unit amount of waste will change year after year - drastic change of waste set-outs will occur in near future?

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 4-1 Conclusions Seasonal variation on waste set-outs Actual condition survey in one district in Fukuoka city, Japan Seasonal variation on waste set-outs Actual condition survey in one district in Fukuoka city, Japan But households who used smaller capacities of waste bag were restricted - between (kg/household/day) But households who used smaller capacities of waste bag were restricted - between (kg/household/day) Seasonal variation really existed - in summer season, households tend to set out - more frequently, more than 2 bags, with smaller capacities - to avoid long storage of waste - to keep from bad smell Seasonal variation really existed - in summer season, households tend to set out - more frequently, more than 2 bags, with smaller capacities - to avoid long storage of waste - to keep from bad smell So, this seasonal change of waste set-outs - very small - negligible So, this seasonal change of waste set-outs - very small - negligible

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul Introduction 2. Materials and Methods 3. Results and Discussion 4. Conclusions 4-2 Conclusions But, we should take care of annual change of waste amount -Amount of waste still continued to decrease gradually - by introducing “pay-as-you-throw” system, -Coverage of each unit amount of waste - very small But, we should take care of annual change of waste amount -Amount of waste still continued to decrease gradually - by introducing “pay-as-you-throw” system, -Coverage of each unit amount of waste - very small Perhaps drastic change of waste set-outs will occur in near future? We should check such change in summer season! - easier for us to find change of waste set-outs We should check such change in summer season! - easier for us to find change of waste set-outs

Shinya Suzuki, Fukuoka University, Japan. APLAS Seoul 2010 Thank you very much for your attention !