Land Pollution – At a Glance
Globally, about 2.01 billion tons of municipal solid waste is generated annually (with at least a third not managed in an environmentally safe manner. High income countries account for only 16% of the population but generate about 34% of the world’s waste.
Over 350 million tons of hazardous waste has been discarded globally so far this year. In just one generation, the production of man-made chemicals has increased by 40,000% from 1 million tons to about 400 million tons annually.
Since the 1950s, the world has produced more than 8.3 billion tonnes of plastic , with 60% of that plastic either ended up in a landfill or the natural environment. Around 300 million tonnes (an equivalent of entire human population) of plastic waste is produced every year.
Waste management is often the highest single budget item ( 20% of municipal budgets ) for local administrations in low-income countries.
With the rapid urbanization, population growth and economic development of countries, landfills, industrial activities, hazardous waste, deforestation, and agricultural activities that pollute the land have increased, leading to over 90% of waste being dumped or burned in low-income countries, toxic pollution that affects over 200 million people across the world- 1 in 3 children affected by lead poisoning and a loss of 24 billion tons of topsoil every year.
Working with local organizations, Pure Earth is an example of an international NGO that is focusing on toxic land pollutions in low- and middle-income countries that affect the health of citizens by offering assessment, remediation, risk mitigation of chemical and legacy toxic hotspots preventing re-contamination and guard against future pollution. Using tools such as the x-ray fluorescence analyzer, toxins in the soil are identified within 30 seconds allowing the rapid location and determination of the extent of contamination and potentially start live-saving cleanup. Recently in collaboration with Netguru, Pure Earth has developed an app, Report Pollution to crowd source pictures and stories of pollution and health impacts, to share with citizens and decision makers for remediation and a public site with APIs for an information platform as part of the Toxic Sites Identification Program.
A recent study conducted in Canada, showed that honey collected from urban beehives can provide an accurate measure of how polluted the city is, thus honey testing provides a way to monitor environmental changes in an area.
Monitoring and information management, serves as an enabler for decision making in solid waste management, information such as the volume of waste being generated in local areas, emissions from landfills, history of waste collection at households, activities of trucks to recovery of fees, access to accurate and timely information allows operators and governments to design and management more efficient waste management systems.
In Quito, Ecuador, the municipal waste collection company, which serves 2.2 million citizens and collects 1900 tons of waste daily, is using a central online data management system to monitor its services in real time, optimizing the management of its internal management system and improving external cleaning services. Using GIS and handheld devices they are also able to monitor household behavior and provide door to door information for citizens to participate in waste collection, scheduling and tracking of routes and local waste disposal sites.
In England, the Greater Manchester waste disposal authority is using big data for planning disposal services, in collaboration with University of Manchester, using the information collected formulate policies for waste management and to incentivize recycling.
Soil contamination can also be detected with hyperspectral imagery (e.g. from aerial monitoring or some satellites) e.g. for heavy metals or uranium tailings.
Of the 2.01 billion tons of municipal solid waste annually, only 19% is recovered through recycling and composting, even though 51% of waste generated in high income countries is recyclable, in low-income countries recyclable waste accounts for only 20% of the waste stream.(World Bank).
As more countries combat the issue of managing solid waste, more waste to energy plants are being built to convert waste using incineration, gasification, pyrolysis or anerobic digestion to produce energy for heating, electricity, biogas and biofertilizer and other materials, In the U.S., there are currently 77 waste-to-energy facilities in 22 states, processing 95,023 tons of waste each day, with the capacity to generate 20,800 gigawatt hours of electricity a year. Europe has over 400 such plants, and another 300 are found in other parts of the world, in Sweden 99.3% of household waste is recycled into energy.
Bioremediation is adjusting the soil's environmental conditions to stimulate microorganisms to break down contaminants in an aerobic (with oxygen) or anaerobic (without oxygen) environment. For an oil spill in Iraq, UNEP provided a demonstration to government officials that the ideal setting for bacteria to speed up and break down the oil was adding nutrients from manure and a bulking agent that consisted of wood chips and water. This method is suitable for most oil spills.
Pure Earth also uses bioremediation techniques such as vermiculture and lime on some of their heavy metal remediation projects.
In some parts of the world, soil pollution is an increasing threat. In China, it is estimated that 20 percent of its farmland is contaminated by heavy metals, prompting a new Soil Pollution Prevention and Control Law that should help focus investment and technology (just as the Superfund did in the US) to address this critical challenge.
Fertilizer innovations using more “controlled release” mechanisms are being developed to allow more precise control of fertilizer release based on the soil’s temperature, acidity, or moisture changes.
Managing wastes on land become much more difficult when these are hazardous and require special ways to monitor and remediate. For example, radiation exposure from contaminated soil, surface or groundwater, and contaminated storage or other infrastructure require special approaches fueled by modern technology.
One of the negative consequences of the accelerated pace of technological obsolescence is discarded electronic waste (e-waste). About 54 million tons of e-waste was generated globally in 2019 (up by 21 percent in five years), with only 17.4 percent collected and recycled. Many innovative approaches are being developed around the world to address this growing problem (see an example from Ghana).
Phytoremediation is cleaning up the environment using plants. Plants will absorb the contaminants through their roots along with water and other elements in the soil. Hence, plants will remove the pollutants from their immediate environment. In Italy, a farmer’s entire herd of sheep that he used to make cheese and provide meat had to be culled when scientists found dioxin poison in his sheep. The contamination came from a steel plant, but the farmer could never graze sheep on his land without a cleanup. The farmer was using industrial hemp to leach contaminants from the soil.
Apps are also being used in waste management, In India an organization called I Got Garbage is operating in several cities, through their app waste pickers are matched with households and businesses that need waste collection services. It supports more than 10000 waste pickers and offers services from waste collection to local organics management and value-added recycling.
Mr. Trash Wheel, is a waste interceptor, that picks up litter floating in the Inner Harbor of Baltimore, Maryland, United States. Its unusual appearance, helps to build public awareness, of proper waste management.it is powered by both water and solar energy, the floating waste collected is moved to a dumpster behind the device, via a conveyor belt. There are currently 3 trash wheels and to date 1478 tons of solid waste have been collected from the Harbor.
Smart solar powered compacting bins are being used in several cities around the world e.g New York , Prague, Nitra, Newcastle these bins use solar energy and sensors to continually compact the waste that is deposited in the bins. In some cities the bins have increased the capacity of up to 700% and reduced collection by up to 85%. The sensors send real time data to online management systems e.g., to signal when the bin is full and needs to be emptied.
Low-income families in developing countries purchase the smallest product they immediately need instead of the large size package. Unfortunately, large-size products are 40 percent cheaper than the equivalent number of small products since marketing and packaging can account for 50 percent of the total cost. The additional price is a poverty tax since families do not have the money to buy the larger package. Environmentally more single use plastic will be disposed of, which will end up in the ocean. Algramo promotes reusable packaging, where they encourage citizens to pay for the product and not the package. Vending machines are used to sell lentils, rice, laundry detergent, and pet food from major manufacturers. The products are 30-40 percent cheaper than other vendors, and there is an additional discount of about 10 percent for reusing the packaging.
The concept is called packaging as a wallet where there is only a one-time charge for the package's life. The system works by having each packaging have an RFID chip refilled using vending machines connected to the IoT. The customer pre-charges their account online or in-store with cash and decides on how much to fill. The unit pricing is the same regardless of the quantity of volume purchased. Currently, Algramo has electric tricycles, which allow for home-based refills. The tricycles have less overhead and are cashless and enable products to be sold 30 percent less than in-store with an additional 11% discount if the customer uses their own packaging.
Circular economy is enabling the conversion of organic waste into energy, heat and natural fertilizer for farmers, In Freetown , Sierra Leone, organic waste, which makes 84% of the city’s waste, that would have been left to decompose in landfills are collected and converted into clean energy, using 40 waste to energy digesters (50-100Kw), called Waste Transformers. The energy generated is currently providing power for a Women’s Hospital. This system solves a part of the shortage of power, reduces the cost waste collection in the city, creating jobs, while providing a fertilizer, called biogas digestates for local farmers. This project is a partnership between, The Waste Transformers and Masada Waste Management Limited. The Waste Transformers have partnered with other organizations to provide similar waste to energy and fertilizer projects in Amsterdam, Netherlands and Cape Town, South Africa.
In many parts of the world, rice farmers do not have good alternatives to dispose of rice straw after a harvest. Burning straw and stubble will release carbon dioxide gas and particulate matter that is detrimental to the environment and humans. Leaving it on the field will release methane gas. An alternative from Thailand is boiling the rice straw without chemicals will convert it to a pulpy mass that will be later processed into biodegradable paper and packaging for the to-go food containers. An estimate on product life is that the rice starch container can stay leakproof from heat, grease, and liquid for two hours.
South Korea is transitioning from the clean to green through various initiatives driven by technology. In the ‘Third Energy Master Plan (2019-2040)’, South Korea plans to significantly cut back coal power and raise the share of renewables to 35% by 2040, in other sectors South Korea has led in various technological innovations towards achieving low carbon green growth, some of which are highlighted below:
In 1999, the Korean Ministry of Environment (MOE) introduced a waste disposal verification system to prevent illegal waste disposal. When the system was first introduced, a paper voucher system was established to track the disposal process and pursue legal action against illegal waste management. However, it was inconvenient for waste generators, transporters, and disposers to process them at the site and was overly time consuming because the vouchers were written by hand and mailed. There were limitations as well, for administrative bodies to prevent illegal activities, as they were unable to track the entire process, and confirm the 26 million vouchers issued every year. In response to these problems, the MOE introduced new technologies and systems for real-time tracking. As a result Allbaro, an online waste disposal verification system was developed.
Allbaro is a comprehensive waste management system, integrating the waste manifest system and other specialized waste treatment systems such as the RFID-based medical waste management system and the construction waste information management system, etc.
Allbaro is composed of three parts: a waste handover system, a waste approval and licensing system, and an analytical processing system. Under the waste handover system, waste generators, transporters, and disposers input information on waste handover (type, amount, and date) on the Internet and can monitor the online process in real time. The electronic transfer forms can be drawn up, waste control register automatically managed and waste record reports can be drawn up and submitted, the license/approval application/modification on waste, statistical data analysis on waste can all be accessed online.
Waste Transfer and Takeover Information Management
It manages the entire waste disposal process, from generation to disposal, by registering waste handover information online or through RFID-based technology. This system prevents illegal waste disposal, as the administrative organizations can verify the information submitted by generators, collectors, and managers in real time.
Waste Authorization & Licensing Process
When industrial waste is generated, or disposed of, the process should be reported or approved, and verification statements should be issued by the administrative organizations. These waste-related authorizations and licensing processes are computerized, which enhances the efficiency of business users and administrative organizations.
Waste Statistical Analysis System
The accumulated waste-related statistics stored in the Allbaro System is used as a critical basis for establishing waste related policy.
RFID technology is used for both landfill management and food waste disposal. Landfill sites rely on accurate weight data to charge for waste disposal. A scale or weighbridge system at the entrance to the site weighs waste vehicles on arrival, records and verifies load data and reweighs the vehicle once the load has been deposited. Data is stored and can be transferred to back office systems in order to meet legislative reporting requirements and improve efficiency.
Citizens also use RFID technologies as they dispose of their food waste by scanning an RFID card on bins installed at their apartment complexes. They are charged according to the weight of what they throw away. They are charged according to the weight of their waste, the waste is processed into feed for livestock and biogas, which is used partly to power the recycling plant. In the last 6 years there has been a reduction of 47000 tons in food waste.
SLC Waste to Energy Town consisting of 폐자원에너지타운, 자연력에너지타운, 바이오에너지타운, 환경문화단지
A comprehensive plan to utilize most potential energy resources was established since 2008 by Korean government, many Waste to Energy (WTE) facilities such as Solid Refuse Fuel (SRF) manufacturing and power plants and bio-gas plants have been newly constructed. Also, the government has promoted energy conversion of WTE plants by segregating waste to produce higher calorific value SRFs and increasing recycling rates as well.
In 2016, about 24% household waste, 6% industrial waste, 18% hazardous waste, 0.5% construction waste in Korea are being used for energy recovery (Seo, Y. C. et al, 2016). The technologies that are currently being used for energy production from waste are thermochemical conversion process like incineration, gasification, pyrolysis; mechanical conversion processes like SRF manufacturing; biological conversion processes like anaerobic digestion for biogas production.
Currently more than 50 combustion (incineration) plants are in commercial operation producing energy from waste. The existing incineration plants are mainly for disposal of waste. However, they are inefficient at electricity production and contribute to air pollution thus, gasification and melting technology have been introduced. There many gasification plants being operated in Korea. The capacity of these plants varies from 10 ton/day to 150 ton/day. Several biodiesel production plants using pyrolysis technologies are under development. The expected outputs of these plants are 55,000 tons/year to 120,000 tons/year (Seo, Y. C. et al, 2016).
Waste containing organic matter can be separated and pelletized into solid fuel. Due to its high heating value (HHV), it is combusted or converted to energy at boilers and cogeneration plants. The Korean government has planned to promote energy conversion efficiencies of WTE plants by segregating waste to produce higher calorific SRF and to increase recycle rates. Currently, biogas produced in Korea from waste is used for heating, electricity or as fuel in thermal power plants. The Biogas comprises of livestock manure, food waste, sewage sludge, organic municipal solid waste, and organic industrial waste using anaerobic processes.
Best Practice of Using Biogas from Landfill
50MW Landfill Gas Electricity Generation
Korea has the world’s largest power plant utilizing landfill gas which could provide electricity for 43,000 of residents. Landfill gas is collected through the header pipe and unwanted gas is treated in an incinerator; and the remaining recyclable gas is transferred to be generated as power or collected and transferred a to leachate treatment or boiler management facility. Landfill gas generated during waste disposal at landfill is collected through horizontal and vertical gas collection pipes installed in the landfill, and all landfill gas captured by the power plants is then converted from gas to energy in a resource recycling system.
This process increases the collection efficiency of landfill gas generated at the landfill sites and gas collected for recycling (50MW Power Plant) through appropriate treatment (incineration) to reduce greenhouse gas emissions. Registered as a CDM (Clean Development Mechanism) project, it has created economic and environmental benefits by generating electric power worth of US $30 million annually and a certified emission reduction of 800,000 CO2 tons.
Conversion Process to Produce Energy from Waste
1) Mechanical conversion – SRF (solid refuse fuel)
Waste and biomass with organic components can be separated and pelletized as solid fuel forms Due to its high heating value, it is combusted or converted to energy at boilers, cogeneration plants.
2) Conventional Thermal conversion – combustion (incineration)
Combustion or Incineration is a conversion or disposal process to burn the organic components in biomass or waste by introducing sufficient air (oxygen) to obtain energy. The existing incineration plants mostly for stable disposal of waste. However, their energy efficiency is very low, sometimes only heat is generated. Due to the emission of air pollutants, it is not sustainable, so gasification and melting technology have been introduced.
3) Thermal conversion – Gasification
Waste gasification technology is to produce synthesis gas (syngas) by reacting waste with partially supplying oxidizing agents (air, oxygen, steam). The main compositions of syngas are the same as fuel gas such as methane (CH4), hydrogen(H2) and carbon monoxide (CO). After purification steps, syngas can be used as a clean fuel. Syngas can be used as fuel for combustion boilers, power generation (gas turbine, steam turbine) and to convert into chemical raw materials (hydrogen, methanol, ammonia, DME, SNG etc.)
Further information on other waste to energy facilities and how they are operated are available from the following videos:
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