DR. AZIL BAHARI ALIAS

SOLID WASTE MANAGEMENT

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SOLID WASTEMANAGEMENT

PRINCIPLESPROCESSING &

TREATMENTFINAL DISPOSAL

IntroductionFramework

Waste quantities and characteristics

Storage & Collection

MRFComposting

Waste-to-EnergyRDF

Sanitary landfill

NON-TECHNICAL CONSIDERATION

RegulatoryFinancialPolicies

Management/ System

Learning outcomesTo explain different the different types of wastes

To define domestic/household/industrial solid wastes

To explain and describe waste generation theory ( able to calculate waste generation per capita)

To describe and analyze waste management hierarchy

Definitions Solid wastes (non hazardous) - wastes arising from human

activities and are normally solid as opposed to liquid or gaseous and are discarded as useless or unwanted.

Focused on urban waste (MSW) generated in residential and commercial environments.

Construction wastes – from work on individual residences and commercial buildings

Demolition waste – dirt, stones, bricks, plastics, lumber, pipes

Agricultural wastes – from agricultural residues, manures

Yard waste – from grass, leaves

Food waste –from household, restaurants, etc.

Add on data on municipal solid waste composition/generation in malaysia – pie chart

(SOURCES: WORLD BANK, 2000)

20??.........City of Garbage!!!!!

Why bother???FLASH FLOOD

1960s

VECTOR & VERMINSDISEASES

Waste generation theoryRaw Materials

Manufacturing

Processing and recovery

Secondary manufacturing

consumer

Final disposal

Raw materials, products and recovered materials

Waste materials

Residential

Commercial

Institutional

Construction & demolitions

Municipal services

Agricultural

Industrial

Municipal Solid Waste

Treatment plant sites(incinerators)

Types & sources

Details: table 3-1 p.41 (textbook)

WASTE CHARACTERIZATION

Physical Chemical Biological

A. Specific weightB. Moisture contentC. Particle size distributionD. Field capacityE. Permeability

A. Proximate analysisB. Ultimate analysisC. Energy content

A. Volatiles solidsB. Lignin contentsC. Biodegradable fractionA. Odors

Physical propertiesA. Specific weight lb/yd3, a volume measure and, therefore, subject to interpretation and variable.

Beware of reporting: loose, as found in containers, un-compacted, compacted.Refer Table 4-1 for typical specific weight range

B. Moisture content Wet-weight relationship:M , eq.4-1, p.72Varies from 15-40%, use 21%, food and yard wastes very high-70%; paper, plastics and inorganics very low-3%.Important consideration for transformation processes: energy recovery (incineration) and composting. Rain soaked trash will way more than its dry counterpart, a consideration at the weighing scales

C. Particle size distribution

Imprint consideration in the recovery of materials, pre-processing antecedent to a classification or sorting process – Screens

D. Field Capacity (FC)

The amount of moisture that can be retained in a waste sample subject to the downward pull of gravity. Water in excess of FC will flow out of the waste as leachate.50-60% for uncompacted, commingled waste from residential and commercial sources.

E. Permeability Measures the movement of gasses and liquids in landfills. K, eq. 4-7, p.76k= 10-11 to 10-12 m2 in the vertical and 10-10 in the horizontal.

Chemical propertiesA. Proximate analysis

Includes the following tests:MoistureVolatile combustible matterFixed carbon (combustible residue after volatile matter is removed)Ash (weight of residue after combustion in an open crucible

B. Ultimate analyses

Determination of the percent C, H, O, N, S, and ash.Opportunity to calculate chemical formula, which then can be used in various chemical and biological reactions.Elemental analyser

C. Energy content

Potentially critical element in incineration. Can be measured or calculated.DuLong Formula:

Btu/lb = 145C +610(H2 - O2/8) + 40S +10N eq.4-10, p.86Constituents are % by weight

D. Fusing point of ash

Define as T at which the ah resulting from the burning of waste will form of solid (clinker) – by fusion and agglomeration Typical fusing T for the formation of clinker from solid waste range from2000-2200°F (1100-1200°C)

Biological propertieso VS, volatile solids, ignition at 550°C is often used as a measure of the biodegradability of the organic fraction.

o Lignin – a polymeric material containing aromatic rings with methoxyl group (-OCH3),-present in some paper products such as newsprint and fiberboard)

o Biodegradable Fraction (BF) – biodegradability of organic compounds (see table 4.7, pg 88) based on lignin content.

BF = 0.83 - 0.028 LC eq.4-11, p.88

o Odors typically result from the anaerobic decomposition of the organic fraction.- Sulfate is reduced to sulfides and the to H2S.- Organic compounds containing a sulfur radical can lead to the formation of methyl mercaptan and aminobutyric acid.-detail pg. 89

100% MSW

90-97% TreatedVia MRF, RDF,

Incineration, Combustion

3-10% DisposedIn SLF

Waste management Hierarchy

Waste

•Recycled Material

(e.g Plastics)•Recovered

Material(e.g Gold, Silver,

Platinum)•New Products

•Methane Gas•Electricity

(Combustion)

Products

Energy

Wealth:Economy

EnvironmentSocial

(Sustainability)

FOUR Rs: REDUCTION

Reduce the amount material used Increasing the lifetime of the product Eliminating the need for product

REUSE Paper bags, newspapers, etc

RECYCLING HDPE, PVC, PP, PS

RECOVERY Process the refuse without prior separation. The desired material are separated at a central facilities (i.e

MRF)

Case StudyDiscuss in a group a case study of solid waste

management for the following continents : Malaysia, Japan, USA, UK, Australia, UAE. Highlight the following elements in your discussion:

Waste generation Waste collection, treatment & disposal system Problems and challenges occurs

Presentation in a group consist of SWM for each country (2 hours)

CALCULATION OF SOLID WASTE GENERATION

Objectives:

Expression for unit waste generation ratesMethods to estimate waste quantities1)Load-count analysis2)Weight-volume analysis3)Material-balance analysis

Calculation of waste generation per capita

IMPORTANCE OF WASTE QUANTITIESCompliance with federal and state waste

diversion programsIn selecting specific equipmentIn designing of waste collection routesMaterials recovery facilities (MRF’s)Disposal facilities

Expression for Unit Waste Generation Rates

Residential Residential Relative stability of residential wastes in Relative stability of residential wastes in a given location, lb/capita.daya given location, lb/capita.day

CommercialCommercial Relate the quantities with the number of Relate the quantities with the number of customers, lb/capita.dycustomers, lb/capita.dy

IndustrialIndustrial Basis of some repeatable measure of Basis of some repeatable measure of production.production.

lb/automobile or lb/plantlb/automobile or lb/plant

AgriculturalAgricultural Basis of some repeatable measure of Basis of some repeatable measure of production.production.

lb of manure/ ton of materiallb of manure/ ton of material

Lb of waste/ ton of raw materialLb of waste/ ton of raw material

Estimation of Solid Waste Quantities

a) Load-count / weight-volume analysis – the number of individual loads and waste characteristics (types, estimated volume)

b) Material mass balance analysis – determine the generation and movement of solid wastes at each generation source. (ex. 6-2, pg132)

c) statistical analysis – to determine the statistical characteristics and the distribution of the waste.

Load count analysis- Example 6.1

Material Balance analysis

Simplified statement

Min Mou

Accumulation = inflow - outflow + generationdM / dt = Min - Mout + rw

dM = rate of change of the weight of material stored (accumulated) within the study unit, lb/day

Min = sum of all the material flowing into the study unit, lb/day Mout = sum of all the material flowing out of study unit, lb/day rw = rate of waste generation, lb/day t = time, day

Note: Always write rw as positive in the parent equation and make a negative substitution as required in the final analysis.

Ex- 6-2, pg 132

A cannery receives on a given day 12 tons of raw produce, 5 tons of Cans, 0.5 tons of cartons

and 0.3 tons of miscellaneous materials. Of the 12 tons of raw produce, 10 tons become

processed product, 1.2 tons end up produce waste, which is fed to cattle, and the remainder

is discharged with the wastewater from the plant. Four tons of the cans are stored internally

for future us, and the remaining is used for package the product. About 3 percent of the cans

used are damaged. Stored separately, the damaged cans are recycled. The cartons are

used for packaging the canned product, except for 5 percent that are damaged and

subsequently separated for recycling . Of the miscellaneous materials, 25 percent is stored

internally for future use,; 50 percent becomes waste paper, of which 35% is separated for

recycling with the remainder being discharged as mixed waste; and 25 percent becomes a

mixture of solid waste materials. Assume the materials separated for recycling and disposal

are collected daily. Prepare a materials balance for the cannery on this day and a materials

flow diagram accounting for all the materials. Also determine the amount of waste per

ton of product.

Solution 1. On the given day

12 tons of raw produced5 tons of cans0.5 tons of cartons0.3 tons of miscellaneous materials

2. As a results of internal activities

a) 10 tons of product is produced, 1.2 tons of produced waste is generated, and the remainder of the produce is discharged with the wastewater

b) 4 tons of cans are stored and the remainder is used, of which 3 percent are damaged

c) 0.5 tons of cans are used of which 3 percent are damaged

d) 25 percent if the miscellaneous materials is stored; 50% becomes paper waste, of which 35 percent is separated and recycled, with the remainder disposed of as mixed solid waste; the remaining 25% of the Miscellaneous materials are disposed of as mixed waste.

Contd…3. Determine the required quantitiesa) Waste generated from raw producei. Solid waste fed to cattle = 1.2 ton (1089 kg)ii. Waste produced discharged with wastewater

= (12-10-1.2) ton= 0.8 ton (726 kg)

b) Cansi. Damaged and recycled = (0.03)(5-4) ton =

0.03 ton ( 27 kg)ii. Used for production of product = (1-0.03) =

0.97 ton (880 kg)

Cntd…C) cartons i. damaged and recycled = (0.03)(0.5 ton) = 0.015 ton ( 14 kg)ii. Cartons used in product= (0.5-0.015) ton= 0.485 ton (440 kg)

d) Miscellaneous materials i. Amount stored = (0.25)(0.3ton)= 0.075 ton(68 kg)ii. Paper separated and recycled – (0.50)(0.35)(0.3 ton)=

0.053 ton ( 48 kg)iii. Mixed waste (0.3-0.075)-0.053 ton = 0.172 ton(156 kg)

e) Total weight of product = (10+0.97+0.485) ton = 11.455 ton ( 10,392 kg)

f) Total material stored = (4+0.075) ton = 4.075 ton ( 3696 kg)

Cntd…4. Prepare a material balance and flow diagram for the cannery

for the day A) The appropriate materials balance equation:

Amount of material stored = inflow – outflow – waste generation

B) the materials balance quantities are as follows: i. material stored= (4.0 + 0.075) ton = 4.075 ton ii. Material input = (12.0+5.0+0.5+0.3) ton = 17.8 ton iii. Material output =

(10+0.97+0.485+1.2+0.03+0.015+0.053) ton = 12.753 ton

iv. Waste generation = (0.8+0.172) ton = 0.972 ton

The final materials balance is 4.075 = 17.8-12.753-0.972 ( mass balance checks)

1. Material Flow Diagram

4.075 t Stored

internally

12 t raw

5 t cans

5 t cartons

0.1 t misc.

11.455 t products

1.2 t waste fed to cattle

0.03 t cans recycled

0.015 t cartons recycled

0.053 t paper recycled

0.8 t waste ProduceDischarge With wastewater

0.172 tMixed waste

Cntd….5. Determine the amount of waste per ton of

product a) Recyclable material=

(1.2+0.03+0.015+0.053)ton/11.455 ton = 0.11 ton/ton

b) Mixed waste = (0.8+0.172) ton / 11.455 ton = 0.085 ton/ton

Statistical analysisFor many large industrial activities but

impractical to provide container capacity to handle the largest conceivable quantity of SW to be generated in a given day

Must be based on the generation rates and characteristics of the collection system

Steps and formulation SEE APPENDIX D –pg 917-929

Example 6.3 (pp. 134)

Factor that Effect Generation Rates Source Reduction and Recycling. Design with disposal in

mind. Public Attitudes and Legislation. If not reimbursed, the

public must be recruited to a "tree saving" mentality. Legislation includes bottle laws, green waste pick-ups.

Geographic and Physical Factors. The bigger the yard and the longer the growing season, the more the waste. Seasonal, fall leaves, Christmas gifts, spring cleanup. Kitchen grinders contribute a minimal reduction.

Frequency. More waste is collected if the frequency is increased. Note that more wastes are not generated.

Variations in distribution

Highly variable, local studies should be considered, collected data is expensive and of limited value; make sure that collected data is useful before collecting.

Location, warmer more affluent communities generate more wastes.

Season, T3-8, p.56, More yard and food wastes in the summer; more glass and metals in the winter.

Economics and others.

Calculation of waste generation per capita

Example 6.4