Phương pháp nghiên cứu thu gom và vận chuyển rác nghiên cứu tại 6 địa bàn của Hà Nội

79 TẠP CHÍ KHOA HỌC VÀ CÔNG NGHỆ Tập 48, số 2, 2010 Tr. 79-89 PHƯƠNG PHÁP NGHIÊN CỨU THU GOM VÀ VẬN CHUYỂN RÁC NGHIÊN CỨU TẠI 6 ĐỊA BÀN CỦA HÀ NỘI NGÔ KIM CHI, NGUYỄN MINH TÂM, ĐẶNG NGỌC PHƯỢNG 1. INTRODUCTION Ha Noi is in the strong urbanization process, the recent population increases 3.45% per year. Living standard of Hanoi citizen increases resulting to domestic waste generation rate increase too with the rate of 0.545 – 0.572 kg/person/day [1]. Hanoi discharged more than 3300 tons/day of household and business waste. Although the waste collection ratio is gradually increasing in recent years but the waste volume is non stop increasing and improving transportation and collection effectiveness is always most important and difficult problem for Hanoi city. Researching waste collection and transportation will contribute to understand the existing situation and then give the effectively proper proposals as well as supervising and assessing tools of waste collection and transportation system [2]. Waste collection and transportation takes the cost of worker, equipment and financial investment for urban solid waste management. Applying the method on time and motion study can assess source separation effectiveness at Nguyen Du ward (0.38 km2, 11315 people, Urban Environmental Company Number 3 with 23 workers are responsible for), Phan Chu Trinh ward (0.41 km2, 8306 people, Urban Environmental Company Number 2 and 23 workers are responsible for), in which organic wastes are transpoted to Cau Dien composting plant, household inorganic waste is discharged into the 240l waste container then dumped at Nam Son landfill site. An expansion in whole Hanoi had launched by the survey at Kim Giang ward (0.22 km2, 10118 people, Thanh Cong cooperative is responsible), Nghia Tan ward (0.57 km2, 22790 people, Tay Do Comopany is responsible) Me Tri (7.06 km2, 22406 people, Thanh Cong cooperative is responsible for) and Dong Anh town (4.57 km2, 28899 people, Dong Anh Urban Environmental Company is responsible for this) [3]. Besides, study was also implemented in said above collection environmental companies to discover the existing status, makes comparison and proposals on solid waste collection and transportation not only for themselves but for other urban environmental companies in Hanoi. 2. METHODOLOGY 2.1. Procedure Waste collection and transportation method was used surveyed forms from making the survey plan of hand push cart/ container and shifting at the loading points (making up the map of loading points, handcart routes, collection shifts, the movement from a loading point to an other, number of loading points and waste amount, working time, start time and the last loading point). The collection and transportation process contains followed stages: 1) Studying the selected areas- making the area map of collection line, table 1) loading point, handcart/collection bin, 80 collection workers (CWs) (collection frequency, number of collection worker, and estimation the waste quantity) ; 2) Unify the sample size: there is twelve lines of hand cart, six lines of lorry at Phan Chu Trinh and Nguyen Du; 3) Traning staff, surveyor and organizing survey; 4) Analysing data; 5) Result- conclusion and proposals. Table 1. Collection shedudle at 6 surveyrd site in Hanoi Figure 1.2. Waste generation frequency of Phan Chu Trinh and Nguyen Du wards 81 2.2 Making the survey form Principal activities need to survey consist of loading point, kind of mobilize waste barrel, lorry, waste level in the barrel and all kinds of waste are encoded to being convenient the date treatment. Survey forms for handcart and waste loading turcks are displayed in the table 2 and table 3. Table 2. Survey form for handcarts Ward: Worker code: Mission: Working time: Survey day : Survey timetable : Weather: Working attitude: Work burden: No Activity Other (note) Start time Finish time Location Note 1 2 Table 3.Survey form for waste loading trucks Ward: Worker code: Mission: Working time : Survey day : Survey timetable Weather: Working attitude: Work burden No Start time , loading point, finish time Meter Coming time Arriving time Number of barrel at the loading point Hand push cart size Waste level in the barrel Waste : household waste/ business/Other Started time of loading waste Finish time of loading waste Waste 1 2... 2.3 Training of the surveyors, organizing of the implementation, fulfill of the forms 2.4 Creating the summary table and analyzing data 2.4.1 General table Table 4. General form for handcart Working shift Worker code 1 2 3 4 5 6 7 8 9 10 11 12 Total Time (ti), h:m:s A, : - : ∑i= Ck . ti Total time Ratio, % A, : - : Ck.ti/∑i=1-12 Ck . ti 100% Total time 100% 82 Table 5. General form for loading truck Organic or Inorganic: Weekdays: Worker code 1_D_1 Shifts day: shift 1 Route numbers of one trip Ward cord Code of loading points (LP)/ Destination, etc. Arrival time Departure time Loading time (depature time- arrival time) inc. waiting time Waiting time at the loading point Travel time (arrival time- depature time) Distance of Collection / Trans- portation Number of Collection Containers Estimated amount of waste Type of Sources h:m:s h:m:s h:m:s h:m:s h:m:s met kg 1.Start 1 6:16:02 - - - - - 2 1 4 6:30:40 6:32:52 0:02:12 0:14:38 6100 2 294 1 3 1 5 6:34:00 6:36:35 0:02:35 0:01:08 300 3 492 1 4 6 6:38:04 6:41:14 0:03:10 0:01:29 700 3 1+2 5 7 6:42:15 6:46:03 0:03:48 0:01:01 200 4 1+2 6 8 6:47:36 7:01:22 0:03:20 0:10:26 0:01:33 400 3 3 7 9 7:04:10 7:10:20 0:06:10 0:02:48 700 8 1 8 10 7:13:50 7:22:54 0:09:04 0:03:30 800 7 1+2 9 11 7:28:32 7:32:35 0:04:03 0:05:38 1300 5 3 10 12 7:35:48 7:46:24 0:10:36 0:03:13 800 11 1 11 13 7:49:06 7:56:20 0:07:14 0:02:42 500 7 1 12. Finish 3 9:28:24 9:42:17 0:13:53 1:32:04 50900 0 2.4.2 Summary table Table 6. Analyzing table for handcart Activity code of worker Working shift Worker code 1 2 3 4 5 6 7 8 9 10 11 12 Total Ratio, % A, : - : Total time 100 B, : - : Total time 100 Total average 100 83 Table 7. Analyzing table for transportation truck code Formular Unit Average Summary table of raw date Distance from garage to the first loading point a m 17963 11319 10000 28307 Distance in the survey area b m 4400 2588 3843 1445 Distance from the survey area to dumping site c m 13838 55219 13400 48697 Time from garage to the first loading point d h:m:s 0:51:44 0:22:13 0:29:06 0:48:19 Collection time in the survey area Loading time e h:m:s 0:37:47 0:22:58 0:44:00 0:26:17 Movement f g-e h:m:s 0:19:25 0:10:02 0:12:58 0:05:49 Total g h:m:s 0:57:12 0:32:16 0:56:57 0:25:40 Time of transporting waste h h:m:s 0:34:18 1:47:15 0:36:48 1:34:27 Stopping time at the dumping site h' h:m:s 0:13:14 0:16:58 0:09:05 0:28:35 Number of loading point in the survey area i 20 7 9 5 Number of waste container of surveyed area j 33 22 47 26 Number of waste in the survey area k kg 2213 2401 2568 3254 Date calculation Loading time/container e/j s/barr el 77.6 65.1 56.3 62.4 Loading time of 1kg (average) e/k s/kg 1.1 0.6 1 0.4 Total of loading time and moving time g/k s/kg 1.7 0.8 1.3 0.5 Velocity from garage to survey area a/1000/d km/h 21.6 25.5 20.9 32.1 Velocity in the survey area b/1000/f km/h 13.9 21.1 18 17.8 Velocity from survey area to the end c/1000/h km/h 24.8 31.8 22.4 33.3 84 III. RESULT AND DISCUSSION 3.1. Investigated results 3.1.1 Results at Phan Chu Trinh, Nguyen Du and four sites in Hanoi Table 8. Daily collection waste quantity in Nguyen Du, Phan Chu Trinh wards Daily waste quantity of each ward (kg) Day 5/8/2008 (Tus) 6/8/2008 (Wed) 7/8/2008 (Thur) 8/8/2008 (Fri) 9/8/2008 (Sat) 10/8/2008 (Sun) 11/8/2008 (Mon) Average Nguyen Du 16025 15833 15362 13105 15008 15690 12865 14841 Phan Chu Trinh 10990 12327 11092 11492 11658 8610 11461 11090 Table 8 shows that, daily waste was quantity collected in Nguyen Du ward is higher than in Phan Chu Trinh ward, Nguyen Du ward need 18 waste collectors for one working day without day-off collectors/shift. One waste collector in Nguyen Du and Phan Chu Trinh wards averagely collected 824.5kg waste/day and 616kg/day respectively. Collected waste in Nguyen Du ward was more effective than in Phan Chu Trinh ward. In the time from 20 pm to 23 pm, 72.9 % of generated waste and collected waste in Nguyen Du ward and 73.5% of them in Phan Chu Trinh ward, table 1, figure 1 and 2. The same calculation with four other areas, in average, Kim Giang ward was 782 kg/person/day, Nghia Tan ward was 847 kg/person/day, Me Tri commune was 640 kg/person/day and Dong Anh town was 503 kg/person/day. Me Tri commune and Dong Anh town has a volume of waste dumped on site then one waste collector collected averagely waste less than others. 3.1.2 Investigative result of collection by hand push cart Surveying activity at three shifts showed that each shift has their typical activities. Although there was the time changing among shifts, main activities takes most of time such as (1)Cleaning the sewage, (2) Sweeping and picking street waste/leaf; (4) Collecting waste barallel; (10) Talking rest; (11) Being on duty at collection point to train citizen; (12) Waiting to loading waste, table 9 and 10. In which Activity 2: This takes much more time, waste collector had to sweep and pick street waste. In fact, they some time had to turn around in one place to pick waste, because of freely discharging. This symptom is normal in the lines which is surface of the road and has business activity, the temporarily discharged places such as tension poles, small markets. Activity 4: Collecting and storing waste bucket at two source separation wards, waste collectors were not only sweeping and picking waste but also distributing waste bucket of 240l (organic and inorganic waste bucket) along the collection points. One worker collected and stored 8 to 10 waste buckets in the rush hour (17h30-18h) within crowded traffic. If citizen would self manage collection points then it will save money and labor of waste worker and equipment finance. Activity 10: In three working shifts, evening had the least rest time, they are quite strenuous, and it should to work in shifts to ensure the fair. Activity 12: Waiting time for loading waste is so 85 long, there is much insufficiency because of no strong relationship among waste collectors and truck driver. Table 9. Ratio of main activities in Phan Chu Trinh and Nguyen Du wards Pilot wards Main activities Wards Working shift Ratio, % 2 4 10 11 12 Nguyen Du Morning, 5 h -15 h 65.73% 2.83% 17.20% 0.00% 7.85% Afternoon, 15 h -2 h 56.01% 8.09% 7.18% 11.56% 4.03% Night, 17 h – 2 h 52.82% 11.10% 6.82% 4.35% 9.87% Phan Chu Trinh Morning, 5 h – 15 h 80.35% 0.00% 11.89% 0.00% 0.79% Afternoon, 15 h – 2 h 74.67% 0.26% 12.68% 0.00% 5.59% Night, 17 h – 2 h 39.28% 5.47% 5.87% 23.64% 9.35% Note: (1)Cleaning the sewage, (2) sweeping and picking up waste/ leaf; (4) collecting and storing waste bucket; (10) having rest; (11) being on duty at collection point to guide citizens; (12) waiting for loading waste Table 10. Main activities at Kim Giang, Me Tri, Nghia Tan and Dong Anh sites Survey areas Main activites Location Working shift Ratio, % 1 2 4 10 12 Kim Giang Morning, 5 h – 15 h 4.00% 73.82% 1.16% 13.35% 0.00% Night 1, 17 h – 12 h 0.00% 45.24% 8.53% 25.39% 5.59% Night 2, 17 h – 2 h 1.93% 58.15% 5.16% 14.41% 7.01% Me Tri Morning 1, 3 h – 10 h 1.04% 48.08% 10.26% 3.87% 18.91% Morning 2, 5 h – 11 h 29.94% 48.82% 3.56% 12.88% 0.00% Nghia Tan Night time, 16 h – 24 h 1.27% 61.21% 4.25% 10.10% 13.93% Dong Anh Morning, 4 h – 10 h 7.22% 72.97% 2.89% 4.81% 0.49% In four expansion sites, there was a change. The activity 1 takes most time, 29.94% in Me Tri commune. Other activities are suitable for each survey areas. 3.1.3 Investigative result of waste transportation by trucks 3.1.3.1 Collection effectiveness, quantity and velocity in Nguyen Du and Phan Chu Trinh wards 86 Table 11. Comparison collection effectiveness between two wards Unit Comparing effectiveness between two wards , average value PCT_Organic PCT_Inorganic ND_Organic ND_inorganic Loading time/container s/ container 77.6 65.1 56.3 62.4 Loading time/1kg waste s/kg 1.1 0.6 1 0.4 Loading time total and moving time/1kg waste s/kg 1.7 0.8 1.3 0.5 Velocity from garage to surveyed wards km/h 21.6 25.5 20.9 32.1 Velocity in the surveyed wards km/h 13.9 21.1 18 17.8 Velocity from surveyed wards to Nam Son/Cau Dien km/h 24.8 31.8 22.4 33.3 Nguyen Du ward loaded organic waste quickly (56.3 s / 77.6 s) because organic waste quantity is not much at collection point, reduction the self loading point and there is a support from waste collectors. If collect organic waste bin at the same location, loading activity will be more convenient but the waste collectors will be harder. Collection effectiveness is higher in Nguyen Du ward, waste quantity is much more, and worker is harder and is hurried. Generally, velocity of the trucks are slow and depending on out side factors such as rush hour, ward geography, traffic density and street area. 3.1.3.2. Collection effectiveness and waste quantity in Kim Giang, Me Tri, Nghia Tan and Dong Anh sites. Table 12. Collection effectiveness at Kim Giang, Me Tri, Nghia Tan and Dong Anh Unit Comparing effectiveness at four wards, average value Kim Giang Me Tri Nghia Tan Dong Anh Loading time/ container s/container 55 68.4 54.7 56.6 Loading time/1kg waste s/kg 0.33 0.26 0.32 0.44 Loading time total and moving time/1 kg waste s/kg 0.35 0.29 0.44 0.76 Velocity from garage to surveyed wards km/h 15.27 22.88 25.45 23.25 Velocity in the surveyed wards km/h 7.08 27.54 20.75 22.03 Velocity from surveyed wards to Nam Son/Cau Dien km/h 23.01 28.73 33.78 28.76 87 Me Tri had the smallest collection time of one kg of waste then Me Tri commune had the largest collection effectiveness. Collection effectiveness in Dong Anh is the least. Me Tri commune has the great quantity of waste (waste are fully and highly stored) so that even loading time/1kg of waste is big but general effectiveness is still higher. Comparison within surveyed sites according to loading time total and moving time in the surveyed area, collection effectiveness of Dong Anh town is not high because the distance between two loading points is quite far (more than 5 km) and the small loading capacity (less than 3 tons) that do not compress waste effectively so that the effectiveness is lesser than using high loading capacity truck. Me Tri commune has only two main loading points along the main and large road so that the moving time is effective, many hand push carts gathered at the loading points making the loading more effectiveness. In general, the trucks run slowly in the survey area for loading waste. Other reasons such as, traffic jam, stopping within traffic light, high traffic density in the survey area also impact working effectiveness of the truck transportation. So that, it need to arrange moving time and collection routes in the street line to reach the optimal collection effectiveness. Average collection effectiveness of organic waste and inorganic waste are 1 s/kg and 0.5 s/kg respectively in two pilot wards. In the four expansion sites, average collection time is 0.34 s/kg. The waste container of 240l collects waste lesser and loading point per 1 kg collected waste is higher. Table 13. Investigative result summary of waste collection at 6 survey areas in Hanoi. Area Area km2 Population (people) Waste quantity (ton/day) Waste quantity (kg/person/day) Number of waste collector (people) Waste quantity of waste collector (kg/person) Nguyen Du 0.38 11315 14.8 1.31 18 824 Phan Chu Trinh 0.41 8306 11.1 1.34 18 616 Nghia Tan 0.57 28899 53.4 1.85 63 847 Kim Giang 0.22 10118 6.3 0.62 8 782 Me Tri commune 7.06 22790 25.6 1.12 40 640 Dong Anh town 4.57 22406 16.1 0.72 32 503 3.2 Conclusion Use the above study methodology allows determining the collection effectiveness and the result show the existing situation. This is one suitable method to survey the waste collection and movement. In two pilot wards, organic waste were separated and dumped at site with the rate of 20% in Nguyen Du ward and 25% in Phan Chu Trinh ward. Activity of freely discharging waste into pavement is still popular. It needs to communicate and remind citizen to over this situation, it will reduce the collection time, it not only increase waste collection effectiveness but also create nice urban lifestyle. Besides, it needs to: 1) Reducing the waiting time for loading waste, loading waste lately to reduce traffic jam, arranging again the collection time of hand push cart. 2) Maintenance sour separation at the collection point, discharging waste properly. 3) Arranging optimal collection routs, manpower of working shifts. 88 4. CONCLUSION, PROPOSAL Method of researching waste collection and transportation is the basic tool for quantitative decription of time and motion of waste and will be an effective tool to survey the solid waste management. This methodology need to supported and documented to do the technical method and tools for determining solid waste collection effectiveness while this method is still lack of technical guide and insufficiency in Vietnam. Acknowledgement: Studied results were based on the survey on time and motion in Phan Chu Trinh and Nguyen Du wards and four sites in Hanoi (Kim Giang, Me Tri, Nghia Tan and Dong Anh) carried out in 2008, with finance supported by JICA-3R Hanoi project, JICA experts guided and discussed detailly of methodology and survey forms. We would like to thank the enthusiastic guides of Mr Hirata, Ms Nguyen Huong Giang and staff of Urban Environmental Company Number 2, 3 and Thanh Cong Cooperative, Tay Do Environmental Company, Dong Anh Environmental Company for suppoting the method and supervising during the implementing all surveys in 2008. REFERENCE 1. Report on solid waste management in Hanoi, JICA-3R-Hanoi project, 2008. 2. Study on solid waste management plan for Ulanbator City, Mongolia, JICA newsletter volume 7. 3. Report on time and motion of waste at Phan Chu Trinh and Nguyen Du, JICA-3R HN project, 2008 4. Annual statistic year book, 2007. SUMMARY STUDY METHOD ON TIME AND MOTION OF SOLID WASTE COLLECTION AND TRANSPORTATION CASE STUDY IN 6 SITES OF HANOI One method of time and motion study on solid waste collection and transportation was used in 6 investigated sites in Hanoi. Survey sheets have been designed and trained to carrying out study waste collection by hand push cart/waste bins along assigned routes and the load by trucks at the loading point in the streets, volume of collected waste, time of loading and transportation, time of each activity of waste collection. The results showed that; sweeping and picking up waste discharged in to the pavements was the most time consuming accounting for 60% of the total time. One waste collector collected an average of about 824kg/person/day, an average volume of 14.8tons/day colleted in Nguyen Du ward; average of 616kg/person/day and the amount of 11 tons/day collected in Phan Chu Trinh ward. The organic waste with about 20-25% of the total generated waste was separated from the normal – landfilled waste going to the Cau Dien composting plant by waste separation at source (WSS) in Phan Chu Trinh and Nguyen Du wards. In other sites without WSS such as Kim Giang, Me Tri, Nghi Tan, Dong Anh town, the volume of waste is 6,3 tons/day, 25,6 tons/day, 53,4 tons/day, 16,1 tons/day respectfully. One waste collector collected an average of 782, 640, 847, 503kg/person/day in Kim Giang, Me Tri, Nghia Tan, Đong Anh town. 89 The results showed that the good habitude of discharging waste at regulated place and time should be maintained and encouraged in order to increase the effectiveness of the waste collection and transportation. The distribution of manpower as well as optimal the collection route and schedule should be done to increase the productivity of waste collection and transportation. The mentioned study method on time and motion of waste collection and transportation as well as its use will create an effective tool and permit to carry out quantitatively the solid waste collection and transportation in Hanoi with the specific characteristics of narrow routes. It is need to detailed and technical document this study method in order to create one useful tool and technical method to investigate municipal solid waste management in Vietnam. Địa chỉ: Nhận bài ngày 12 tháng 4 năm 2009 Liên hiệp Khoa học sản xuất Công nghệ Hoá học, Viện Khoa học và Công nghệ Việt Nam.