Introduction to Solid Waste Management

Introduction to Solid Waste

• Solid waste accumulates at the point of creation.
• Categorization is based on the economic sector responsible for the waste.

Types of Solid Waste

Mining Waste

• Generated in three ways: surface materials left behind from mining, tailings stored in ponds, and drainage with hazardous materials.

Agricultural Waste

• Includes waste from livestock and crop harvesting.
• 90% is repurposed as fertilizer.

Industrial Solid Waste

• Waste from non-mining industrial processes.
• Estimated annual production is 200-600 million metric tons.
• Includes demolition waste, sludge, and combustion ash.

Municipal Solid Waste (MSW)

• Unwanted materials discarded by people.
• Annual production is 210 million metric tons.
• Includes items like broken or worn-out products, temporary-use items (like magazines, bottles).

Understanding Municipal Solid Waste

• Discarded items include broken or worn-out products, or temporary-use products.
• Temporary use products (magazines, bottles) generate much of the waste.

U.S. Municipal Solid Waste Statistics

• Annual generation is 230 million metric tons of MSW.
• Per capita waste is 2 kg (4.4 lbs) daily. This has increased by 70% since 1960.

Municipal Solid Waste Generation Rates

• A graph shows total and net generation of MSW per capita over the years.
• Higher living standards correlate with increased per capita waste.

Waste Generation Based on Living Standards

• Higher living standards correlate with increased per capita waste.

Waste Disposal Methods

• Traditional methods include dumping outside city limits, often burned. Continuous use in remote areas.
• Modern techniques include landfills, incineration, source reduction, composting, and recycling.
• Current methods include windrow systems, aerated piles, and enclosed vessels.

Landfill Management

• Municipal landfills use impermeable clay layers and membranes.
• Mechanisms for managing liquid and gas outputs.
• Cost-effective but poor design creates environmental concerns.
• Visual representation of landfill management practices.
• Decrease in the number of U.S. landfills over time.

Incineration Process

• Controlled burning of refuse.
• 12% of U.S. municipal solid waste is incinerated.
• Heat can be captured for electricity, offsetting disposal costs.
• Risks include air quality issues and concentrated toxic ash.

Challenges of Incineration

• Despite regulations, pollutants may still be released.
• Construction costs of incinerators are between $50 million and $400 million.
• U.S. EPA is skeptical of new waste-to-energy facilities and prefers recycling.

Source Reduction

• Prevent waste generation at the source, by wise material selection.
• Focus on designing, purchasing, and utilizing materials effectively.

Practicing Source Reduction

• Design changes reduce packaging waste, notably on soft drink bottles.
• Efficiency enhancements in production processes.

Avoiding Waste Generation

• Recommendations to reduce hazardous materials and reuse items to slow entry into the waste stream.

Economic Incentives for Waste Reduction

• Businesses benefit from minimized waste, which reduces disposal costs and pollution.

Composting

• Uses natural decomposition for organic waste.
• Can be implemented on a small scale (backyard composting).
• Benefits of composting are illustrated through visual aids.
• Approximate 3,800 facilities are operating across the U.S.

Recycling Overview

• Includes recycling and composting.
• Accounted for approximately 35% of solid waste stream diverted from disposal in 2011.
• Economic incentives (e.g., deposit-refund programs) lead to significant increase in beverage container disposal rates.
• Laws in some states require waste separation by residents and businesses, which leads to higher rates of recycling.

Historical Recycling Rates, Curbside Recycling Programs, Innovative Recycling Initiatives

• Graph showing recycling rates from 1960–2012.
• Specific material recycling rates of 2012.
• Significant increase in curbside recycling programs from 1990 to 2011, serving the population.
• Incentives like Recyclebank illustrate success of recycling programs.

Recycling Challenges, Environmental Impact of Plastics, Increasing Plastic Waste

• Technical issues with the diversity of recyclable plastics.
• Plastic bag issues impacting marine life.
• Graph depicting plastic proportion increasing in trash over decades.
• Comparison of municipal solid waste disposal methods globally.

Changes in Waste Disposal Methods Over Time

• Graph illustration of the shift in waste disposal methods from 1960 to 2012.