Module 4 PDF Notes - lecture note PDF

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MODULE 4 4.0 COLLECTION AND TRANSPORTATION o The most importation element o The most costly functional element Activities: o Picking up solid wastes o Hauling wastes to new location o Unloading the collection vehicle 4.1

Collection Services

4.1.1 Municipal collection o Curb, alley, backyard or setout-setback o Daily collection or every 2 days o Manual method used include lifting and carrying loaded containers to collection vehicle, rolling container to the vehicle and emptying the containers 4.1.2 Commercial, Industrial and High-rise apartment collection o For larger apartment building o Residential complexes o Daily collection (early morning/late evening) o Large containers – moveable or stationary with compactor to reduce volume 4.2

Collection Methods

The most important and costly functional element is collection (60-80% of total cost). Methods of collection will significantly influence the quality and quantity of recovered material and the mode of disposal. 4 types collection methods: 4.2.1 Communal Collection o The house owners take the wastes to the collection point. o The waste collector will collect the waste from the communal storage bin o Commonly used in high-rise apartments, condominium, markets, hawker centres, commercial areas. 4.2.2 Block Collection o The householders deliver the waste to the collection vehicle o Collection intervals 2-3 times a week o Arrival of vehicle is informed by ringing a bell or familiar musical note 4.2.3 Curbside Collection o The residents will place the wastes in bins by the roadside

o After collection, the empty bins are taken back by owners o Waste sorting may also were carried out by residents, or by waste collector 4.2.4 Door to Door Collection o Curbe service: terrace and link house o Alley service or back lane collection o Set-out set-back service: 2 group of collector ( to clear bins & to return the bins) o Set-out service: collection from individual houses, bungalow o Backyard service: sack is used to collect refuse from few houses and emptied into collection vehicle 4.3 Type of Collection System Collection system based on mode of operation 4.3.1 Hauled-Container Systems (HCS) o Containers used for the storage of wastes are hauled to the processing, transfer, or disposal site, emptied, and returned to either their original location or some other location. o Suitable for complex apartments, shopping centres o 2 types: tilt-frame container, and trash-trailer. o The collector is responsible for driving the vehicle, loading and unloading empty containers, and emptying the contents of the container at the disposal site. 4.3.2 Stationary-Container System (SCS) o Containers used for the storage of wastes remain at the point of waste generation, and the empty collection vehicle will collect the waste from one point to the next containers. o 2 types of stationary-container systems: self-loading compactors and manually loaded vehicles o Vehicles equipped with a compaction mechanism. Suitable for smaller generation-rate-house to house collection. o Trips to the disposal site, transfer station, or landfill made after collection vehicle is full.

4.4

Analysis of Collection Time

Stationary Container System

Exchange container mode

(0.10 – 0.25)

5. COLLECTION ROUTES Once equipment and labour requirements have been determined, collection routes must be laid out so that both the collectors and equipment are used effectively. In general, the layout of collection routes involves a series of trials. There is no universal set of rules that can be applied to all situations. Some heuristic guidelines that should be taken into consideration when laying out routes are as follows: 1. Existing policies and regulations related to such items as the point of collection and frequency of collection must be identified. 2. Existing system characteristics such as crew size and vehicle types must be coordinated. 3. Wherever possible, routes should be laid out so that they begin and end near arterial streets, using topographical and physical barriers as route boundaries. 4. In hilly area, routes should start at the top of the grade and proceed downhill as the vehicle becomes loaded. 5. Routes should be laid out so that the last container to be collected on the route is located nearest to the disposal site. 6. Wastes generated at traffic-congested locations should be collected as early in the day as possible. 7. Sources at which extremely large quantities of wastes are generated should be serviced during the first part of the day. 8. Scattered pickup points (where small quantities of solid waste are generated) that receive the same collection frequency should, if possible, be serviced during one trip or on the same day. 5.1    

Establishing collection routes Preparation of location maps of the waste generation sources, Data analysis Preliminary layout of routes, Evaluation of the preliminary routes and the development of balanced routes by successive trials....