Unit III Collection & Transfer Syllabus Methods of collection – Types of vehicles –Manpower requirement – Collection routes –Transfer Stations – Selection of locations, operations & maintenance –Options under Indian conditions

Introduction In the Municipal Solid waste Management system, Collection is an important aspect. Collection of solid waste in urban area is difficult and complex because generation of solid waste takes place in every home, every apartment, and every commercial and industrial facilities as well as in the streets, parks and even vacant areas. The mushroom-like development of suburbs further complicated the collection.

Amount of money spent for collection, transportation and disposal of solid waste, approximately 50 to 70% spent for collection phase. Waste Collection Includes not only gathering or picking up from various sources, but also hauling to location of collection vehicle emptied. The unloading of collection vehicle also considered.

Waste collection is carried out in 5 different phases as discussed below:

Phase 1: The individual house owner must transfer whatever is considered as waste to the refuse can, which may be inside (or) outside the home. Phase 2: The movement of the refuse can to the truck, which is usually done by the collection crew, called backyard collection. The can is moved to the street by the home occupant, the system is called, curb side collection

Phase 3: More & more separated materials and yard wastes are collected separately either in same truck (or) in separate vehicles from house to house. Phase 4: This phase is known as “truck routing”. The trucks must collect the refuse from many homes in the most efficient way possible. Phase 5: The fifth phase of the collection system involves the location of the final destination (e.g: MRF, disposal site, transfer station)

Methods of collection of Waste From Low-Rise Detached Buildings: The most common types of residential collection services include 1. Curb 2. Alley 3. Setout-setback and 4. Setout

Curb service: The homeowner is responsible for placing the containers to be emptied at curb on collection day and return the empty container to storage location until the next collection. 2. Alleys: part of layout of city or given residential area, alley storage of containers is common method.

Setout-setback: containers are setout from the homeowner’s property and setback the emptied container by collection crew. Setout: same as setout-setback service, expect that the homeowner responsible for returning the containers to their storage location.

Collection Waste placed at Curb by Manually and Mechanically

Satellite Vehicle Collection System

From Low- and Medium-Rise Apartments Curbside collection service is common. Maintenance staff responsible for transporting the containers to the street for curbside collection by manual or mechanical means. Where large containers used, the containers emptied mechanically using collection vehicles equipped with unloading mechanisms.

From High-Rise Apartments Mostly Large containers are used. Depending on size and type of container used, it may be emptied mechanically. Sometimes, the loaded containers may be hauled to an off-site location(e.g. materials recovery facility)

From Commercial-Industrial Facilities Both manual and mechanical means used. To avoid traffic congestion during day, wastes collected in the late evening and early morning hours. Where manual collection used, waste are put into plastic bags, cardboard boxes and other disposable containers placed at curb for collection.

If congestion is not a major problem and space for storing containers is available, collection service provided on the use of -movable containers, - large container with stationary compactors -large capacity open-top containers. Based on size, it may be emptied mechanically.

Types of Collection System According to mode of operation collection system classified into two categories: Hauled Container system (HCS) Storage containers hauled to disposal site, emptied and return to original or some other locations. 2. Stationary Container System (SCS) Storage containers remain at the point of generation, except moved to curb or other location to empty.

Hauled Container system (HCS) Suitable for removal of waste where the rate of generation is high. It reduces handling time It requires only one truck and driver Three main types of HCS 1. Hoist Truck 2. Tilt-Frame container 3. Trash-Trailer

Capacities of containers available for use in HCS Vehicle Container type Container capacity (yd3) Hoist Truck Used with stationary compactor 6 – 12 Tilt-frame Open top called drop or debris box Equipped with self compaction 12 – 50 15 – 40 20 – 40 Truck-tractor Open top trash-trailers Enclosed trailer mounted containers equipped with self-contained compaction mechanism

Hoist Truck

Tilt-frame

Truck-tractor

Personnel requirements for HCS Mostly a single collector – driver used. He is responsible for driving the vehicle, loading full containers onto vehicle, emptying the contents at disposal site (or transfer point) and redepositing the empty containers. Some cases, for safety reasons, both driver and helper used. Helper responsible for attaching and detaching chains or cables used in vehicles. A driver and helper always used where hazardous wastes to be handled.

Stationary Container System (SCS) Two main types: 1.Systems with mechanically loaded collection vehicles 2. Systems with manually loaded collection vehicles. Nowadays, all the collection vehicles equipped with internal compaction mechanisms.

Capacities of containers available for use in SCS Vehicle Container type Container capacity (yd3) Compactor, mechanically loaded Enclosed top and side - loading 1 – 8 Special containers used for the collection of residential wastes from individual residences 0.23 – 0.45 Compactor, manually loaded Small plastic or galvanized metal containers, disposable paper and plastic bags 0.08 – 0.21

Mechanically loaded collection vehicles

Manually loaded collection vehicles

Personnel requirements for SCS It depends on collection vehicle loaded mechanically or manually For mechanically loaded, a driver with helper used. Helper bringing loaded container to collection vehicle and returning the empty container. Occasionally, a driver and two helpers used where the containers to be emptied must be rolled to collection vehicle from inaccessible locations.

Where the collection vehicle loaded manually, For curb or alley service, two collector and a driver used. For backyard carry service a multiperson crew is used. In satellite-vehicle collection systems, one collector-driver used. In many cities multiperson crews are used for curb service as well as for back yard carry service.

Types of Collection Vehicles Almost all collections are based on collector and collection crews, which move through the collection service area with a vehicle for collecting the waste material. The collection vehicle selected must be appropriate to the terrain, type and density of waste generation. The most commonly used collection vehicle is the dump truck fitted with a hydraulic lifting mechanism.

A description of some vehicles types follows: Small-Scale Collection & Muscle-powered Vehicles Non-Compactor Trucks & Compactor Trucks (i) Small-scale Collection & Muscle Powered Vehicles: These are common vehicles used for waste collection in many countries and are generally used in rural hilly areas. These can be small rickshaws, carts, (or) wagons pulled by people (or) animals, and are less expensive, easier to build and maintain compared to other vehicles.

They are suitable for densely populated areas with narrow lanes, and squatter settlements, where there is relatively low volume of waste generated.

Non-Compactor Trucks: Non-Compactor trucks are efficient and cost effective in small cities and in areas where wastes tend to be very dense and have only little potential for compaction. When these trucks are used for waste collection, they need a dumping system to easily discharge the waste. It is generally required to cover the trucks in order to prevent residue flying off (or) rain soaking the wastes.

Trucks with capacities of 10-12 m3 are effective, if the distance between the disposal site and the collection area is less than 15Km. Non-compactor are generally used when labour cost is high.

Compactor Trucks: Compactor vehicles are more common these days, generally having capacities of 12-15 m3 due to limitations imposed by narrow roads. The weight of solid wastes collected per trip is 2 to 2.5 times larger since the wastes are hydraulically compacted. A compactor truck allows waste containers to be emptied into the vehicle from the rear, front (or) side.

Rear loading Packer truck

The advantages of the compactor collection vehicles include the following: (a) Container are uniform, large, covered and relatively visually inoffensive. (b) Waste is set out in containers so that the crew can pick them up quickly. ( c ) Health risks to the collectors and odour on the streets are minimized. (d) Waste is relatively inaccessible to the waste pickers.

Collection Vehicle Routing Efficient routing and re-routing of solid waste collection vehicles can help to decrease the cost by reducing the labour expended for collection. Routing procedures usually consists of the following two separate components: (a) Macro Routing – Defining size of routes (b) Micro Routing – Defining exact path of each route

Macro Routing It consists of dividing the total collection area into routes, in such a way as to represent a day’s collection for each crew. The size of each route depends on the amount of wastes collected per stop, distance between stops, loading time and traffic conditions. Natural barriers such as rail road embankments, rivers and roads with heavy competing traffic, can be used to divide route territories. As much as possible, the size and shape of route areas should be balanced.

Micro Routing: Using the results of the macro-routing analysis, micro-routing can define the specific path that each crew and collection vehicle will take on each collection day.

Results of micro-routing analysis should also be done by the review of experienced collection drivers.

Deciding Factors for Collection Vehicle Routing: The trial & error route development process is a relatively simple manual approach that applies specific routing patterns to block configurations. The map should show collection service locations, disposal (or) transfer sites, one-way streets, natural barriers and the area of heavy traffic flows.

Then, routes should be traced out onto the tracing paper using the following factors: (a) Routes should not be fragmented (or) overlapping. (b) Total collection (+) Hauling time reasonably constant for each route in the community. ( c ) The collection route should be started as close to the garage (or) motor pool as possible. (d) Heavily travelled streets should not be visited during rush hours.

(e) In case of one-way streets, it is best to start the route near the upper end of the street. (f) In case of dead-end streets, wastes must be collected by walking down, reversing the vehicle (or) taking a U-turn. (g) Higher elevations should be at the start of the route. (h) For collection from one side of the street at a time, it is generally best to route with many anti-clockwise turns around the blocks.

Based on the above rules, a typical vehicle routing is illustrated below:

Transfer Stations When the waste disposal unit is remote to the collection area, a transfer station is employed. A transfer station is an intermediate station between final disposal option and collection point in order to increase the efficiency of the system, as collection vehicles & crew remain closer to routes. In some situations, the transfer stations serves as a pre-processing plant, where wastes are dewatered & compressed. A centralized sorting and recovery of recyclable materials are also carried out at the transfer station.

Basic Transfer Technologies:

Types of Transfer Stations: Depending upon the size, transfer stations can be either of the following types: (i) Small to Medium Transfer Stations (ii) Large Transfer Stations

Small to Medium Transfer Stations: These are direct discharge station that provides no intermediate waste storage area. The capacities are generally small ( < 100 tonnes/day) and medium ( 100-300 tonnes/day) These stations includes a recyclable material separation and processing units. The required over all station capacity (number & size of containers) depends on the size and population density of the area served and the frequency of the collection.

Large Transfer Stations These are designed for heavy commercial use by private and municipal collection vehicles. The typical operational procedure for a larger station is as follows: When collection vehicles arrive at the site, they are checked in for billing, weighted and directed to the appropriate dumping area. Collection vehicles travel to the dumping area and empty the wastes into a waiting trailer, a pit (or) a platform.

After unloading, the collection vehicle leaves the site, and there is no need to weigh the departing vehicle, if its weight (empty) is known. Transfer vehicles are weighed either during (or) after loading, trailers can be more consistently loaded to just under maximum legal weights and this maximize payloads and minimizes weight violations.

Benefits of Transfer Stations: Reduces overall community truck traffic by consolidating smaller loads into larger vehicles. It offers more flexibility in waste handling and disposal options. It reduces air pollution, fuel consumption and road wear by consolidating trash into fewer vehicles. Allows for screening of wastes for special handling. Reduces the traffic at disposal facility. Offers citizens facilities for convenient drop-off of waste and recyclables.

Factors Affecting Site Selection (or) Location of Transfer Stations Site selection should be based on following criteria: Selecting sites that have direct access to truck routes, highways and rail terminals. Providing adequate space within the facility site so that customers waiting to use the transfer station do not interrupt traffic on public roads. Arranging the site so that traffic flows are not adjacent to properties that are sensitive to noise. The site should large enough to accommodate all required functions and possibly future expansion should be centrally located in the area where waste is generated.

Operation & Maintenance of a Transfer Station Six categories can be finalized and can be explained under “Operation & Maintenance of a Transfer Station”. They are: (i) Operation & Maintenance plans (ii) Facility Operating Time (iii) Interacting with the people (iv)Waste Screening (v)Emergency Situation (vi)Record Keeping

Operation & Maintenance Plans Operating a successful station involves properly executing many tasks Facility operating schedules, including days of the week, hours each day & holidays. Staffing plan that lists duties by job title, minimum staffing levels and typical work schedules. Description of acceptable & unacceptable wastes. Operating methods for each component of the facility & description of maintenance procedure for each component. Employee training Safety rules & regulations Recordkeeping procedures Emergency Procedures

Facility Operating Hours Operating hours need to consider neighboring land uses, as well as the operating hours of disposal sites. Depends on individual circumstances. Many large facilities located in urban industrial zones operate 24 hours, 7 days / week. Suburban & rural transfer stations commonly open early in the morning (6.am to 7.am) and close in the late afternoon (4.pm to 5.pm) In many cases, the best trailer must be loaded with sufficient time to reach the disposal site before it closes (4.pm to 6.pm)

Interacting with the Public Every transfer station has its neighbors, whether they are industrial, commercial, residential (or) merely a vacant land. When developing a community outreach plan, transfer station operators should consider the following: Develop a clear explanation of the need for the transfer stations & its benefits. Develop a clear process for addressing community concerns. Designate one person as official contact for neighborhood questions & queries Organize periodic facility tours. Establish positive relationships by working with community based organizations

Waste Screening Transfer station operators should screen for unacceptable materials before, during & after customers unload. And operators should tell customers where they can dispose off wastes.

Emergency Situations Transfer station operators should prepare for emergency, at minimum, the following emergency events should be anticipated. Power Failure: The plan should address how to record customer information, collect fees and load transfer trailers during a power outage. Unavailability of Transfer Vehicles: The plan should address what to do if poor weather, road closures (or) strikes prevent empty transfer vehicles from arriving at the transfer station.

Unavailability of Scales: The plan should describe record keeping and fee assessment in the event that scales are inoperable. Fire: Fire response and containment procedures should address fire’s found in incoming loads, temporary storage, compaction equipment, transfer vehicles and other locations. Injuries to employees (or) customers: The plan should include first aid procedures and emergency phone numbers of nearby hospitals.

Record Keeping Medium & large transfer stations typically record the following information as part of their routine works. Incoming Loads: date, time, company, driver name, truck number, origin of load, fee charged. Outgoing Loads: date, time, company, driver name, truck number, type of waste. Facility operating log: Noting any unusual events during the operating day.

Complaint Log: Noting the date, time, complaining party, nature of the complaint. Accidents (or) releases: Details of any accident (or) waste releases into the environment. Maintenance Records: For mobile and fixed equipments.