Solid Waste Management

Solid Waste Management Maribel U. Cruz , M.D.

Session Objectives 1. 2. 3. 4. 5. 6.

To define solid wastes and solid waste management To enumerate the general categories, types and sources of solid wastes To describe the situation regarding solid waste disposal in the Philippines To describe the waste hierarchy of SWM To cite the objectives of SWM To enumerate and explain the elements of SWM

Solid Waste Definition : All wastes arising from human & animal activities that are normally solid & that are discarded as useless or unwanted Three General Categories 4. Municipal wastes 5. Industrial wastes 6. Hazardous wastes

Municipal Solid Wastes Food wastes or Garbage Rubbish : paper, cardboard, plastic, textiles, rubber, leather, wood, glass, cans, metals Ashes & residues: materials remaining from the burning of wood, coal & other combustible wastes Demolition & construction wastes: stone, concrete, brick, lumber, plumbing, heating & electrical parts

Municipal Solid Wastes Special wastes: street sweepings, roadside litter, dead animals, abandoned vehicles, discarded appliances

Industrial Wastes Wastes arising from industrial activities and typically include rubbish, ashes, demolition and construction wastes, special wastes and hazardous wastes. Can include treatment plant wastes

Hazardous Wastes Wastes that pose a substantial danger immediately or over a period of time to human, plant & animal life Wastes which exhibit any of the ff; > Ignitability > Corrosivity > Reactivity > Toxicity

Types & Sources of Solid Wastes 1. 2. 3. 4. 5.

Household wastes Commercial & industrial wastes Farm & agricultural wastes Institutional wastes Miscellaneous & special wastes > sludge from water & waste water treatment plants, ash from incinerators street sweepings, demolition, constructions

Situationer

2. 3. 4.

5.

Problems associated with solid waste disposal: Pollution of water and food resources Burning of solid wastes destroys the fertility of the soil Exposure to smoke & fumes from burning wastes increases their risk of developing respiratory diseases Solid wastes become breeding sites of disease vectors

Situationer 1997 – means of solid waste disposal by HH nationwide included the following: > Individual burning – 48% > Municipal garbage collection – 30% > Open dumping – 6% > Burying – 5% > Composting – 4% > others – 7% Source: Solid Waste Management Bureau

Solid Waste Management Indicators Philippines 2003 Indicator MSW generated (tons/year) Collection efficiency Percentage waste recovered & reused

National

MM

10 million

2.5 mil

Urban 73% Rural 40% 13%

83%

Percentage MSW composted

10%

Percentage MSW recycled & sold

5%

Percentage of MSW disposed in controlled dumps No. of disposal facilities

25% 6-12% 30%

909

8

Situationer 2004 – MM generated more than 2 million tons of potentially recyclable materials > Plastic is the most common material recycled followed by metal, paper and glass MM generated 6,700 tons of garbage daily

Situationer 

In MM sources of wastes are: > households 74.1% > shops 9.4% > markets 7.6% > restaurants 7.5% > institutions 0.8% > street sweepings 0.4% > river clean-up 0.14%

Situationer 

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In MM, 90% of the wastes are collected by municipal collection system of which: > 25% are illegally dumped > 30% are collected by sanitary landfills > 33% are disposed in open dumps > 2% is recycled Of the remaining wastes that are collected, 4% are recycled by HH while 6% are selfdisposed generally into the river systems

Data from 47 municipalities revealed that 36% had waste recycling programs On the industrial side, among the 368 business establishments that were surveyed: > 49% - used public facilities > 25% - private contractors > 8% - composting > 7% - landfill > 4% - recycling > 1% - incineration

Solid Waste Management 

Definition: Interrelated system of appropriate technologies and mechanisms involved in the generation, collection, storage and processing, transfer & transport , and disposal of solid wastes at the lowest possible cost and risk to the health of the people and their environment.

National Solid Waste Management System Framework 2. 3. 4. 5.

Policy Objectives: Reduction of wastes generated at the source The reduction of wastes to extend the serviceability of final disposal sites Improvement of collection efficiency The provision of safe, environmentally friendly & acceptable way of disposing waste collected from source

Waste Hierarchy 

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Refers to an ordered sequence of initiatives that can be used to identify steps in addressing the amount of waste produced by society Waste avoidance  Reuse  Recovery  Recycling  Disposal

Functional Elements of Solid Waste Management 1. 2. 3. 4. 5. 6.

Waste Generation On-site handling, storage & processing Collection Transfer & Transport Processing and recovery Disposal

Solid Waste Generation

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Definition : refers to the act or process of producing waste Source Reduction : reduction of solid waste before it enters the solid waste stream 3Rs of Solid Waste Mgt. at the source: Reduce- avoid wasteful consumption of goods & minimize waste Reuse- recovering materials intended for the same or different purpose without altering its physical characteristics Recycle-solid waste materials are transformed into new materials

On-Site Storage 2. 3. 4. 5. 6.

Containers for on-site storage should meet the following requirements: Provided with fitting covers to prevent access to flies and rodents Sufficient in size or number to store all the wastes between collection Made of water-proof material Small enough to be carried easily when filled with wastes Accessible to the collector, not subject to flooding & located away from food storage

On-Site Storage 

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Ecological Solid Waste Management Act of 2000 provides that segregation of wastes shall be primarily conducted at the source Wastes shall be segregated into biodegradable and non- biodegradable

Refuse Collection 2. 3.

4.

Important points to consider in solid waste collection are: Regular collection is necessary to avoid problems of storage Vehicles transporting refuse should be properly covered to prevent foul odors, eye-sores access to flies & scattering of waste materials in the streets The route to the final destination site should be as direct as possible from the point of origin & should avoid busy streets

Transfer and Transport Refers to the means & facilities used to effect the transfer of wastes from relatively small to larger vehicles & to transport them to processing centers or disposal sites

Processing Techniques Mechanical volume reduction Compaction Balling of papers for recycling Used to increase the life of landfills 2. Thermal volume reduction Incineration can reduce the volume of wastes by more than 90% Generation of toxic air pollutants: dioxins and furans 1.

Processing Techniques 3. Manual component separation Can be accomplished at the source, transfer stations, centralized processing stations or disposal sites Materials to be sorted or salvaged are: cardboard & high quality paper, newsprint, aluminum cans, glass, iron metals

Resource Recovery 

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Refer to the collection, extraction or sorting of recyclable materials from the waste stream for purpose of recycling, generating energy or production of a product for beneficial use The recyclable items are bought by manufacturing plants for processing to produce goods

Disposal of Solid Wastes In the homes particularly in rural areas, solid wastes may be disposed of satisfactorily in the ff. ways: 2. Burial- deposit solid wastes in pits & covered with soil > pit should be located at least 25 m. away from any well used for water supply 2. Open burning

3. Feeding to animals 4. Composting – controlled decomposition of organic matter by micro-organisms mainly bacteria & fungi, into humus-like product 5. Grinding & disposal sewer – “garbage grinders” attached to kitchen sinks 6. Sanitary Landfill- involves controlled disposal of solid wastes on or in the upper layer of earth’s mantle

Criteria for Establishment of a Sanitary Landfill 1.

Liners – a system of clay or geosynthetic membranes used to contain the leachate and to prevent contaminant flow to groundwater

6.

Leachate collection & treatment system > installation of pipes at the low areas of the liner to collect leachate for storage & eventual treatment & discharge

3. Gas control recovery system > series of vertical pipes or horizontal trenches containing permeable materials and perforated piping to collect gas for treatment of use as an energy source 4. Groundwater monitoring system – takes water samples representative of ground water quality 5. Cover – 2 forms of cover consisting of soil & geosynthetic materials to protect the waste materials

6. A daily cover is placed over the waste at the close of each day’s operations 7. A final cover or cap w/c is the material placed over the completed landfill to control infiltration of water, gas emission to the atmosphere & erosion

Summary  2. 3. 4. 5. 6. 7.

We have discussed: Definition of solid waste and solid waste management Three general categories, types and sources of solid waste Situation regarding solid waste disposal Waste hierarchy Objectives of solid waste management Elements of SWM

Health Care Waste Management

Session Objectives 1. 2. 3. 4. 5.

To define health care waste To enumerate the categories of HCW and cite examples for each To describe the health care waste minimization scheme To describe the color coding scheme for HCW To cite the practices that should be observed in HCW management

Session Objectives 6. To discuss the different processes in health care waste treatment 7. To discuss the waste disposal systems for HCW

National Objectives for 2005-2010 Health care waste segregation, treatment and disposal are improved Indicators 3. Percentage of health care facilities disposing infectious & hazardous wastes according to approved means Target: 80% Baseline: 51% in NCR, DOH 1997 

Indicators , cont. 2. Number of approved healthcare waste treatment facilities at the regional level Target: at least 1 per region Baseline: 3 in Southern Tagalog, 1 in NCR Source: DENR, 2002 3. Number of healthcare facilities served by approved disposal facilities Target: at least one per region Baseline: to be determined

Indicators, cont. 4. Percentage of healthcare facilities practicing proper waste segregation Target: 100% of DOH hospitals Baseline: 69% of DOH hospitals Source: DOH, 2004

A study of 144 private & government hospitals in MM showed that > 86% practiced waste segregation > 59% pre-treated hazardous wastes chemical disinfection and autoclaving Waste collection was done by: > MMDA (38.9%) > Private contractors (35.4%) > Networking with other hospitals with incinerators (12.9%)

Health Care Waste 

2. 3. 4. 5.

Includes all the wastes that is generated or produced as a result of any of the following activities: Diagnosis, treatment or immunization of human beings or animals Research pertaining to the above activities Production or testing of biologicals Waste originating from minor or scattered sources

Categories of Health Care Waste 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

General waste Infectious waste Pathological waste Sharps Pharmaceutical waste Genotoxic waste Chemical waste Waste with high content of Heavy metals Pressurized containers Radioactive waste

General Waste  

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Comparable to domestic waste Comes costly from the administrative or housekeeping functions of health care establishments May also include waste generated during maintenance of health care premises Does not pose special handling problem or hazard to human health or to the environment

Infectious Waste  

Waste is suspected to contain pathogens This includes: Cultures & stocks or infectious agents from laboratory work Waste from surgery & autopsies on patients with infectious diseases Waste from infected patients in isolation wards

Infectious waste Wastes that has been in contact with infected patients undergoing hemodialysis Infected animals from laboratories Any other instruments or materials that have been in contact with infected patients or animals

Pathological Waste 

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Consist of tissues, organs, body parts, human fetus and animal carcasses, blood & body fluids Anatomical waste- recognizable human or animal body parts Can also be considered as a subcategory of infectious wastes

Sharps 

Includes needles, syringes, scalpels, saws, blades, broken glass, infusions sets, knives, nails & any other items that can cause a cut or puncture wounds

Pharmaceutical Waste 

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Includes expired, unused, spilt, and contaminated pharmaceutical products, drugs, vaccines and sera that are no longer required and need to be disposed of appropriately Also includes discarded items used in handling of pharmaceuticals

Genotoxic Waste 

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Includes cytostatic drugs, vomit, urine or feces from patients treated with cytostatic drugs, chemicals and radioactive materials Highly hazardous and may have mutagenic, teratogenic or carcinogenic properties

Chemical Waste 

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Consist of solid, liquid and gaseous chemicals from diagnostic, experimental work, cleaning & housekeeping and disinfecting procedures Maybe considered as hazardous or nonhazardous

Chemical Waste 

Chemical waste is considered hazardous if it has at least one of the following properties Toxic Corrosive Flammable Reactive Genotoxic

Waste with High Content of Heavy Metals Wastes with a high metal content Represent a subcategory of hazardous chemical waste & are usually highly toxic Mercury wastes generated from spillage of broken clinical equipment Cadmium waste comes from discarded batteries Reinforced wood panels containing lead

Pressurized Containers 

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Includes gases which are stored in pressurized cylinders, cartridges and aerosol cans Whether inert or potentially harmful, gases in pressurized containers should always be handled with care

Radioactive Wastes 

Includes disused sealed radiation sources, liquid & gaseous materials contaminated with radioactivity, excreta of patients who underwent radionuclide diagnostic and therapeutic applications , paper cups, straws, needles & syringes, test tubes, & tap water washings of such paraphernalia

Waste Minimization 

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Centered on the elimination or reduction of the health care waste stream Consist of source reduction, recycling, treatment and residual disposal Prior to the implementation of a waste minimization program, it is important to develop a baseline data of the amount of waste generated

Principles of Waste Minimization     

Identify waste generation rates, current hazardous waste management strategies Commitment of health care establishment operators/owners to waste minimization Includes a written policy with specific goals, objectives & timeliness Train employees in hazardous waste handling & site specific waste minimization methods Be aware of and keep updated on the hazardous materials regulations

Methods of Waste Minimization 

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Eliminate use of a material or generate less waste Re-use Recycling Segregation of wastes Composting

Color Coding Scheme for Health Care Waste    

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Black – non-infectious waste Green – non-infectious wet waste Yellow – infectious & pathological waste Yellow with black band – chemical waste including those with heavy metals Orange – Radioactive waste Red – sharps & pressurized containers

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The following practices should be observed: Residuals of the general health care waste should join the domestic waste or municipal solid waste Sharps should all be collected together & placed in puncture proof containers with fitted covers Bags & containers for infectious waste should be marked with the international infectious substance symbol

Highly infectious waste & other hazardous waste should be treated immediately Cytotoxic waste should be collected in leak proof containers clearly labeled “Cytotoxic wastes” Radioactive waste should be segregated accdg. to its physical form & to its half-life and potency

Large quantities of chemical waste should be packed in chemical resistant containers & sent to specialized treatment facilities Wastes with a high content of heavy metals (e.g. cadmium or mercury) should be collected separately & sent to a waste treatment facility Aerosol containers may be collected with the general health care waste. They should not be burnt or incinerated. Anatomical waste should be disposed of in accordance with the local custom

Health Care Waste Treatment 

Aim: to change the biological & chemical character of the waste to minimize its potential to cause harm Incineration used to be the method of choice in treating health care wastes Most common technologies & processes are: thermal, chemical, irradiation, biological processes, encapsulation and inertization

Thermal Processes  

Rely on high heat to destroy pathogens Autoclave > uses high temperature & high pressure steam sterilization to inactivate most microorganisms > used for sterilization of reusable medical equipment

Chemical Disinfection 

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Presently being applied for treatment of health care waste Aldehydes, Chlorine compounds, phenolic compounds, etc. are added to waste to kill or inactivate pathogens Most suitable in treating blood, urine, stools and sewage or in treating infectious wastes containing pathogens

Biological Processes 

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Uses an enzyme mixture to decontaminate health care wastes Requires regulation of ph, enzyme level, temperature & other variables Design application is mainly for regional health care waste treatment centers Composting & vermiculture for treating and disposing of placental waste, food waste, yard trimmings & other organic wastes

Radiation Technology 

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Wastes containign potentially infectious microorganisms ( sewage sludge, biomedical wastes, wastewater) are treated using irradiation systems Four main elements of the waste handling system are: 1. Identification of the contaminated waste 2. Collection 3. Sterilization 4. Final disposal or recycling

Encapsulation  

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Appropriate for disposal of sharps & chemical and pharmaceutical residues Uses either cubic boxes made of high density polyethylene or metallic drums that are ¾ filled with sharps or chemical or pharmaceutical residues Containers are filled up with a medium like plastic foam, bituminous sand & cement mortar Reduces the risk of scavengers gaining access to health care wastes

Inertization  

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Suitable for pharmaceutical waste Involves the mixing of waste with cement & other substances before disposal Minimize the risk of toxic substances in the waste from migrating into the surface water or groundwater Mixture composed of 65% pharmaceutical waste, 15% lime, 15% cement, & 5% water

Waste Disposal Systems 

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Sanitary Landfill – designed to keep the waste isolated from the environment Safe burial on Hospital premises Septic or concrete vault – for the disposal of used sharps & syringes

Burial on Hospital Premises   

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Burial site should be lined with a material of low permeability like clay Only hazardous health care wastes should be buried Large quantities (>1kg) of chemical & pharmaceutical wastes should not be buried Burial site should be managed as a landfill

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Burial pit should be downhill & about 50 meters away from any body of water The bottom of the pit should be at least 1.5 meters higher than the ground water level On-site burial is for limited period of 1-2 years only & for small amounts of wastes ( 5-10 tons in total)

Summary  2. 3. 4. 5. 6. 7. 8.

We have discussed: Definition of health care waste Categories of health care wastes Health care waste Minimization Program Color coding scheme for HCW Practices that should be observed in health care waste disposal Processes in HCW treatment Waste disposal systems for HCW