DEGRADABLE AND NON DEGRADABLE FRACTION OF SOLID WASTE THROUGH AN OPEN LOOP APPROACH
3.1INTRODUCTION
The waste within households, communities, markets, and public service actions is an inevitable byproduct of human activities. These activities are domestic, agricultural, commercial, industrial, and satisfying the growing needs of habitats resulting in the generation of waste. Due to growing industrialization, urbanization, and prospering economy in India, the production of Municipal Solid Wastes (MSW) has increased to a large extent which results in difficulties for its management to people and urban local bodies (ULB). The generation of solid waste, composition, and treatment methods varies for different countries depending upon the existing management system, prevailing economic conditions, and other associated factors. The mismanagement of solid waste and unscientific disposal may lead to health hazards and environmental problems. Thus, the generated solid waste, if managed properly, can be reused as a source for energy generation and fuel recovery. The proper management of garbage needs cooperation and collaboration for efficient delivery and comprises the aspects for the production of waste, collection, transportation, recycling, treatment, and final disposal. The MSW is termed as unwanted material generated from various activities from residential, commercial, institutional sectors, agricultural activities, etc. The US Environmental Protection Agency defines MSW as trash or garbage which consists of everyday items like furniture, clothing, grass, packaging, food scraps, appliances, packaging, etc. that comes from schools, hospitals, homes, and business. The different sources of MSW were shown in Figure 3.1. The municipal solid waste mainly arises from household waste and commercial waste, including degradable and non-degradable matters. The generated waste is heterogeneous, constituting paper, plastic, food waste, glass, metals, textiles, yard waste, and other miscellaneous materials. The generation and management of MSW have emerged as a growing problem at worldwide, regional, and local levels due to economic development and the fast-growing population in developing countries. The problems due to different issues, including urbanization, increased the population and increased consumption of goods and services, thereby increasing the generation of waste. The ineffective problem management of waste majorly in urban areas is because of the unscientific approach for waste management, which has worsened the problems of environmental pollution, the health of people, hygiene. Thus, for effective and sustainable management of waste, source, and composition, the rate of waste generation, collection, transportation, pretreatment, and disposal methods need to be understood.
Figure 3.1 Municipal Solid Wastes Sources
Additionally, the disposal of waste in open land is a common practice in most developing countries. This method of disposing of waste in public areas causes severe health hazards and adverse environmental effects. So, the construction of an engineered landfill is one of the practical and environmentally acceptable methods of disposing of waste. The biodegradable and nonbiodegradable fraction of MSW hurts both soil and groundwater. The leachate generated due to the decomposition of garbage migrates through soil, leading to contamination of soil and groundwater. Leachate is a brown liquid containing heavy metals, toxic chemicals including solvent, organic, or inorganic salts affecting the groundwater and soil properties. The dumping of waste thus severely affects the engineering properties of soil like compressibility, permeability, shear strength, California Bearing Ratio (CBR) values, and other related parameters. Further, continuous disposal leads to the settlement of soil and causes structural damage to the landfill. The solution of contaminated soil and MSW is complicated because of biodegradability, heterogeneous nature, and density variability of waste. Thus, the analysis of geotechnical properties and settlement behavior of land is essential for consideration of the end-use of landfills for recreational purposes. The waste dumped in the landfill site decomposed due to the presence of a significant amount of organic matter presents, thus causing a considerable amount of settlement. The settlement of MSW occurs over a long period, which can be up to 30-50% of the initial height of the waste and contributes to different settlement rates. The settlement of MSW is due to high compressibility under the influence of biodegradation of organic content and overburden load. The overburden load in landfill occurs due to additional overlying waste layer and thus increasing the stress at various depths. Additionally, stability is a significant concern to be overlooked during the designing of landfills. The disposal of waste creates challenges for landfill designing and operation, mostly in hilly terrain. The elaborate characteristics and composition of waste, thus making it necessary for analyzing settlement, slope stability, seepage, and cracking of components of landfills. Therefore, despite explaining the characteristics of waste for management and selecting suitable treatment options, the geotechnical aspects of waste, soil, and settlement behavior of MSW need to be considered for determining the structural stability and designing the landfill.
3.2 WASTE GENERATION
3.2.1 GLOBAL WASTE GENERATION
Breaking of the ecological diversity in the environment those results in environmental pollution is the main factor caused by humans. The growing population and increase in consumption have resulted in a large production of waste worldwide. The developed countries are having a high rate of per-person waste generation as compared to developing, which is mainly influenced by public habits, the lifestyle of habitats, and economic growth. As per the report of the World Bank, the total solid waste generation is expected to increase from 2.01 billion tons in the year 2016 to 3.4 billion tons in the next 30 years. The age of MSW across the globe was estimated to be 13.3% of the total waste generated and is increasing at a very high rate. As per the report of the World Bank, presently, the global annual generation of waste is expected to grow from 2.01 billion tons in 2016 to 3.4 billion tons over the next 30 years.
In September 2018, the World Bank announced that our global waste production is predicted to rise by 70 percent by 2050 unless we take urgent action. Humankind currently produces two billion tons of waste per year, between 7.6 billion people. Population increase may be part of the problem. Still, it’s levels of consumption within a handful of developed nations, and their gross mismanagement of waste, that have led to this environmental catastrophe. The United States is the biggest generator of waste per capita worldwide, with each citizen producing an average of 808 kilograms per year – almost a tonne – and more than doubles that of citizens of Japan. However, as the Global Waste Index highlights, it’s not just the generation of waste that will threaten our planet in the upcoming decades – but the way we choose to manage it.
The Global Waste Index offers a comprehensive breakdown of the most environmentally-friendly methods of waste management. It ranks the 36 countries within the Organization for Economic Co-operation and Development (OECD) according to how effectively they manage their waste per capita.
3.3 FACTORS:
On a per capita level, we uncovered the amount of waste in each country that ends up recycled, incinerated, on a landfill site, on an open dump, or unaccounted for – i.e., untraced – over a year.
Waste Generated Per Capita: The kilograms of waste produced per person.
Recycled: The kilograms of waste converted into new materials.
Incineration: The kilograms of waste disposed of via controlled combustion.
Landfill: The kilograms of waste disposed of via burial.All types of landfill sites were included (unspecified, sanitary, controlled).
Open Dump: The kilograms of waste dumped illegally.
Unaccounted: the kilograms of untraceable waste.
3.3.1 RECYCLING:
Recycling is the process of converting waste materials into new materials and objects. The recyclability of a substance depends on its ability to reacquire the properties it had in its virgin state. It is an alternative to “conventional” waste disposal that can save material and help lower greenhouse gas emissions. Recycling can prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, thereby reducing: energy usage, air pollution (from incineration), and water pollution (from landfilling).
Recycling is a critical component of modern waste reduction and is the third component of the “Reduce, Reuse, and Recycle” waste hierarchy. Thus, recycling aims at environmental sustainability by substituting raw material inputs into and redirecting waste outputs out of the economic system.
There are some ISO standards related to recycling, such as ISO 15270:2008 for plastics waste and ISO 14001:2015 for environmental management control of recycling practice.
Recyclable materials: It includes many kinds of glass, paper, cardboard, metal, plastic, tires, textiles, batteries, and electronics. The composting or other reuse of biodegradable waste—such as food or garden waste—is also a form of recycling. Materials to be recycled are either delivered to a household recycling center or picked up from curbside bins, then sorted, cleaned, and reprocessed into new materials destined for manufacturing new products.
In the strictest sense, recycling of a material would produce a fresh supply of the same content—for example used office paper would be converted into new office paper or used polystyrene foam into original polystyrene. This is accomplished when recycling certain types of materials, such as metal cans, which can become a can again and again, indefinitely, without losing purity in the product.[6] However, this is often difficult or too expensive (compared with producing the same product from raw materials or other sources), so “recycling” of many products or materials involves their reuse in providing different materials (for example, paperboard) instead. Another form of recycling is the salvage of certain materials from complex products, either due to their intrinsic value (such as lead from car batteries, or gold from printed circuit boards) or due to their hazardous nature (e.g., removal and reuse of mercury from thermometers and thermostats).
3.5 TREATMENT OF DEGRADABLE AND NON DEGRADABLE FRACTION OF SOLID WASTE MANAGEMENT:
The biodegradable fraction of SW consists of organic substrates of volatile solids (VS)
and ash. In the bioconversion processes, the potential will be observed in biodegradable volatile solids (VS) fraction mainly because of the presence of refractory volatile solids (RVs).
Generally, the organic fraction of solid waste is nearly 50 – 60% and has higher moisture content and is considered to be a sufficient feedstock for the biological processes.
In the 1990s, commercial and pilot scale degradation of organic wastes was performed
using anaerobic digestion (AD). In anaerobic digestion, solid waste materials are reduced before disposal into the environment. Several anaerobic microorganisms decompose complex organic matters into simpler forms and generate methane and CO2. This conversion of SW to safer and simpler ways is performed by different groups of fermentative, acetogenic, syntrophic, and the importance of cross disciplines on sustainable CE. This may consist of a smart energy concept, monitoring and protect the possibilities of any possible environmental degradation during waste valorization, collection of data through IoT etc. identified the shortcomings in applying the methodological approach to Circular Integrated Solid Waste Management System (CISWMS) and suggested that they can be resolved by expanding the boundaries of linear Integrated Solid Waste Management System (ISWMS). They also pointed out that for CISWMS, the environmental and economic benefits are yet to visible in the field level, and yet further study is required. Summary of some of the recent research works and their inferences on the circular economy.
A nonbiodegradable material is known as a substance that cannot be fragmented down
by microorganisms or natural organisms and is a significant source of pollution. Nonbiodegradable wastes neither get decomposed nor dissolved by natural agents. Various researches on recycled materials from nonbiodegradable solid wastes and their application. These wastes continue to remain on earth for centuries without any degradation. Thus, the threat, which is caused by these wastes, is far more critical than the biodegradable waste.
Moreover, these wastes cannot be decomposed and often get accumulated to make the biological cycles slow and toxic. There are two types of nonbiodegradable wastes- wastes, which can be recycled known as ―Recyclable waste‖ and which can’t be recycled known as Non-recyclable waste. There is an urgent need to increase the amount of waste that can be recycled and reused, especially in the construction industry. This will generate not only a potential business opportunity but also employment generation and environmental sustainability. Reuse is defined as using an unused or a waste product without many transformations and even without altering its shape and is original. Reuse means that a lesser amount of solid waste is produced. These waste products, which are discarded, can be used by those who require it. Various types of solid scraps that can be reused in construction activities are plastic, timber, glass, concrete, and ferrous as well as non-ferrous metals. Reuse of plastic can help in plastic – soil paver blocks for non-load bearing structures, and the timber products help in providing a framework and be reused several times. Glass helps in the production of construction activities such as tiles, bricks, and paver blocks and can be reused. Concrete from construction and demolished sites can be reused as temporary work. Ferrous and non-ferrous metals are used for the formwork of metals and can be used several times.
3.6 THE PROPOSED CIRCULAR ECONOMY MODEL:
The figures 3.2 are immense, meaning that there has to be a great deal of hidden potential. When considering this, we should ask ourselves – how can we make the whole lifecycle more efficient, reduce our production and consumption levels, and bring some of the generated waste back into the life cycle? The new approach is called the “Circular economy” since more material can “be kept” in the circle of production and consumption.
Figure 3.2 circular economy model
The representation of Environmental, Social, and Economic win of the Circular Economy is shown in the below figure 3.3.
Figure 3.3 flow of a circular economy
3.5.1 OPEN LOOP APPROACH:
Open-loop recycling means that a material is not recycled indefinitely and is eventually excluded from the utilization loop and becomes waste. The diagram in Figure 3.3 shows a material flow through the linear (open-loop) system. In this representation, stocks are shown with rectangular boxes, and transforming processes are demonstrated by hexagon boxes.
In Figure 3.3 below, we see that natural resources extracted from the environment are transformed into a product via the manufacturing process. After its use, the product may be discarded as one of the outputs:
(a) A whole product that is not needed anymore
(b) An entire product that became obsolete (although still functional)
(c) Non-functional or old product because of its limited lifetime
(d) Recyclable/reusable parts or scrapped materials and
Those outputs enter one of the post-use channels – reuse, recycle, and garbage disposal, the latter contributing to the landfill. Reuse channel is usually limited, just postponing garbage disposal. Recycling loop results in producing another material, which is typical of lower grade and purity than the original article. It may be transformed further into a different product, which, after use, creates similar outputs. In the long run, a small part of the first resource may be stuck in the loop, but the majority of it becomes disposed of.
Figure 3.4 open-loop approach flow
The bottom line is: even if recycling and reuse are involved, eventual down-grading renders material non-usable, and it contributes to waste generation at the end of the lifecycle. Open-loop recycling postpones disposal and slows down the extraction of new natural resources but does not provide the ultimate solution to the problem.
The law also emphasizes that the products manufactured should be designed to minimize waste and ensure waste recovery and reuse. It is also planned for zero waste from 2009, resulting in 50 % of waste is recycled. Implementing EU guidelines, the law was revised in 2012, including an improved environment, climate, and resource protection. CE entered with the road-map to a support efficient Europe, and it was announced as a Circular Economy Package and upgraded to an Action Plan for the Circular Economy. Later the action plan proposed the amendment to legislation relating specifically to waste and landfills. However, the CE policies were formulated based on the general robust waste policies practiced
India’s circular economy aims to unlock climate-resilient growth and the national policymakers to develop an economic model based on recycling, reusing, and repairing raw materials and products. Government of India has launched National Biotechnology Development Strategy 2015-2020 to develop a bio-manufacturing hub and significantly invest in creating new biotech
products, develop infrastructure for R& D, commercialization and empower India’s human resources (https:// pib.nic.in/newsite/PrintRelease.aspx?relid=134035, Venkata Mohan et al., 2018). India is planning a sustainable economy by encompassing the domain of food, energy,
resource recovery, diagnostics, health care, and environment utilizing renewable resources for the
production of biobased products and biofuels (Venkata Mohan et al., 2018 and 2019).
The advancement of technologies also plays a crucial role in effecting practicing of solid waste management in the current scenario.
3.6 IoT-ENABLED SERVICE IN WASTE MANAGEMENT
Internet of Thing (IoT) is one of the smart communication technologies that interconnect
ordinary physical objects to the Internet and provides intelligent services (Atzori et al., 2010; Hannan et al., 2018). The concept of IoT envisioned connecting different kinds of sensors and actuators to the Internet via heterogeneous access networks enabled by various technologies. The main difference between the Internet and IoT is Internet connects intelligent devices. In contrast, IoT has the additional sensing layer and combines among the non-intelligent or weakly-intelligent methods to interpret the data effectively and provide smart services. IoT works under three visions like things oriented‖ ―Internet-oriented‖ and ―semantic-oriented‖ (Fig.10) (Giusto et al., 2010, Atzori et al., 2010; Bandyopadhyay et al., 2011; Malina et al., 2016). In smart city infrastructure, solid waste management (SWM) is one of the essential domains to be effectively monitored and managed. The IoT concept could be used for the process of tracking, collecting, segregating, transporting, storing, treatment, and disposal of SWM systems. By using sensors, the data collected from the garbage bins are sent through a gateway using the Lora transceiver module and sent to the cloud over the Internet using the MQTT (Message Queue Telemetry Transport) protocol. No SQL is a database that will be used to collect and store those data. It is inferred that the use of LoRa enables long-distance data transmission along with low power consumption as compared to wifi, Bluetooth, or Zigbee. ICT is playing a significant role in collection and resource recycling, and it has been established in China that 49 urban mining pilots implementing intelligent group (Xue et al., 2019). Human-human interaction collection (HH) and Human- Machine (HM) interaction collection are practiced. HH is drilled with several ICT tools by five steps: the generator gets an appointment about collection time and item using a smartphone
App, the server assigns collection order to the nearby location, the collector collects at the door, the collector sends the information to the server, and the generator receives the credit. WIFI or GPRS are used for data accomplishment. In HM, the collection is done by the machine. The machine is embedded with ICT devices such as sensors, barcodes, and data communication devices. First, the tool identifies the generator account, who has already registered, and then, the generator hands over the recyclable materials, followed by the computer sending the information to the server, and then, the generator will be credited. ICT tools barcode identifier, sensor monitors the recyclable data, and GSM/GPRS transmits to the server. The intelligent collection is an organized collection, and in the normative group, the system can identify the location and track the logistic
routes; data are accurate, traceable, and instant, have adapted material and cash flow. The
intelligent collection increases the recycling rate to 35 % by 2020 (Xue et al., 2019).
Intelligent Transportation Systems (ITS) include IoT components such as RFIDs, sensors,
cameras, actuators, and surveillance systems for efficient waste collection. Advanced Decision Support System (DSS) incorporates a model for data sharing between truck drivers in real-time to perform waste collection and dynamic route optimization using IoT components. The SWW is the real field data; hence, it is advisable to design a cloud system for the organization of waste collection processes and applications for waste truck drivers. Software-as-a-service (SaaS) to the commercial waste management company was used. The study inferred that implementing onboard surveillance cameras in conjunction with a cloud DSS system and dynamic routing models can give a significant increase in cost-effectiveness.
Figure 3.5 IoT enable service in waste management
The Internet of Things” paradigm as a result of the convergence of different visions are shown in the below picture 3.6.
Figure 3.6 Internet of Things” paradigm as a result of the convergence of different visions
3.6.1 METHODOLOGY
Software
Hardware
3.6.1.1 SOFTWARE:
The Raspberry Pi is a series of small single-board computers developed in the United Kingdom by the Raspberry Pi Foundation to promote the teaching of basic computer science in schools and developing countries. The original model became far more popular than anticipated, selling outside its target market for uses such as robotics. It now is widely used even in research projects, such as for weather monitoring, because of its low-cost and portability. It does not include peripherals (such as keyboards and mice) or cases. However, some accessories have been involved in several official and unofficial bundles. The organization behind the Raspberry Pi consists of two arms. The first two models were developed by the Raspberry Pi Foundation. After the Pi Model B was released, the Foundation set up Raspberry Pi Trading, with Eben Upton as CEO, to develop the third model, the B+. Raspberry Pi Trading is responsible for developing technology while the Foundation is an educational charity to promote the teaching of basic computer science in schools and developing countries. According to the Raspberry Pi Foundation, more than 5 million Raspberry Pis were sold by February 2015, making it the best-selling British computer. By November 2016, they had sold 11 million units, and 12.5 million by March 2017, making it the third best-selling “general-purpose computer.” In July 2017, sales reached nearly 15 million. In March 2018, sales reached 19 million. In December 2019, sales reached 30 Million. Most Pis are made in a Sony factory in Pencoed, Wales, while others are made in China and Japan.
Figure 3.7 Raspberry pi 3
3.6.1.2 HARDWARE:
- ULTRASONIC SENSOR:
An ultrasonic sensor is an instrument that measures the distance to an object using ultrasonic sound waves. An ultrasonic sensor uses a transducer to send and receive ultrasonic pulses that relay back information about an object’s proximity. An ultrasonic sensor is an electronic device that measures the distance of a target object by emitting ultrasonic sound waves and converts the reflected sound into an electrical signal. Ultrasonic waves travel faster than the speed of audible sound (i.e., the music that humans can hear). Under the Waste Act, waste holders, such as private individuals, property owners, or companies, are primarily responsible for the management of waste. An exception to this rule is the responsibility municipalities, and certain manufacturers may have for organizing waste management.
Ultrasonic sensors work by emitting sound waves at a frequency too high for humans to hear. They then wait for the sound to be reflected, calculating the distance based on the time required. This is similar to how radar measures the time it takes a radio wave to return after hitting an object.
While some sensors use a separate sound emitter and receiver, it’s also possible to combine these into one package device, having an ultrasonic element alternate between emitting and receiving signals. This type of sensor can be manufactured in a smaller package than with separate elements, which is convenient for applications where size is at a premium.
While radar and ultrasonic sensors can be used for some of the same purposes, sound-based sensors are readily available—they can be had for just a couple dollars in some cases—and in certain situations, they may detect objects more effectively than radar.
For instance, while radar, or even light-based sensors, have a difficult time correctly processing clear plastic, ultrasonic sensors have no problem with this. They’re unaffected by the color of the material they are sensing.
On the other hand, if an object is made out of a material that absorbs sound or is shaped in such a way that it reflects the sound waves away from the receiver, readings will be unreliable.
If you need to measure the specific distance from your sensor, this can be calculated based on this formula:
Distance = ½ T x C
(T = Time and C = the speed of sound)
At 20°C (68°F), the speed of sound is 343 meters/second (1125 feet/second), but this varies depending on temperature and humidity. Robot navigation comes to mind, as well as factory automation. Water-level sensing is another good use and can be accomplished by positioning one sensor above a water surface. Another aquatic application is to use these sensors to “see” the bottom of a body of water, traveling through the water, but reflecting off the bottom surface below.
Though it might not be immediately apparent, if configured correctly, ultrasonic sensors can even measure fluid flow rates. In the simplest case, an emitter and a receiver (separate in this configuration) are aligned with the flow of a fluid. Since sound is traveling through a moving medium, the speed of sound relative to these elements will be increased or decreased by the velocity of the liquid. This can be applied to flow inside pipes by aligning these two elements at an angle to each other, calculating the effective velocity increase based on the trigonometric relations between the two.
Flow rate accuracy can be increased by using data from multiple ultrasonic elements, giving results accurate to within a fraction of a percent.
- The ultrasonic sensors sense the distance.
- The data recorded by the ultrasonic sensors is sent to the wifi module through the Arduino Uno
- . The wifi module sends a notification to the servers, in turn, notified the authorities with the required data.
- ARDUINO MEGA
Arduino is an open-source prototyping platform used for building electronics projects. It consists of both physical programmable circuit board and software or IDE (Integrated Development Environment) that runs on your computer, where you can write and upload the computer code to the physical board. The Arduino Mega is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. The 8-bit board with 54 digital pins, 16 analog inputs, and four serial ports. The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with an AC-to-DC adapter or battery to get started. The Mega 2560 board is compatible with most shields designed for the Uno and the former boards Duemilanove or Diecimila.
Figure 3.8 Arduino Mega
FLOW CHART:
The flow chart representations of the IoT enable service in solid waste management are shown below.
Figure 3.7 flow chart representations
3.7 RESULTS AND DISCUSSION
It is potentially cheap and straightforward to implement, making it ideal for use in well-defined systems was the relationship between input and output is direct and not influenced by any outside disturbances. The stability can be measure in the process. It is more stable when compared to the existing approach.
Figure 3.9 stability
The Percentage weight loss of plastics in the simulator as a function of incubation time are shown in the below picture 3.10.
Figure 3.10 Percentage of weight loss Vs. Incubation time.
The Total gas production from the simulators with various plastics and synthetic MSW are shown in figure 3.11.
Figure 3.12 gas production Vs. time
3.8 SUMMARY
The present review explores the potential of biodegradable and nonbiodegradable fractions of solid waste through a closed-loop integrated refinery process for the recovery of bioenergy and value-added products. The integrated refinery processes target for zero waste discharge, considering the trash from one process will be the feedstock for other means is a superior approach for the sustainable valorization of solid waste. The central concept of this integrated refinery processes is to shift the paradigm from a linear economy to circular for a greener footprint. It is a need to change the conventional disposal of solid waste to a closed-loop integrated refinery approach, which is sustainable that could promote an efficient economy and reduce the environmental impacts. The study infers that treating the biodegradable fraction of waste with simultaneous production of bioenergy and recycling, reusing, and recovering the nonbiodegradable fraction of waste will pave a path toward a circular economy. The study has discussed in detail about the liquid and gaseous biofuels synthesized from the biodegradable fraction of waste and their applications in internal combustion engines as single fuel and multifuel
engines. The non-biodegrade fraction of solid waste that could be recovered and reused for different applications such as construction, pavement, etc., Also, the study discusses the circular economy’s policies, which helps to stimulate the economy of the country and identify the pathways to maximize the local resources. The paper also briefly reviews that IoT based technologies are useful tools to tackle the problems faced by the present stable waste management system.