5^th World Convention on Recycling and Waste Management September 11-12, 2017 Singapore

How to Produce Energy from Waste

The most common and popular method for waste to energy generation is ‘Incineration‘. Incineration is also a very highly debated technology, due to the concerns it raises regarding safety and environmental impact. In simple terms it stands for a type of waste treatment process, where the organics from the waste collected are burnt at high temperatures. Waste treatments that are conducted involving high temperatures are called Thermal treatment. The heat generated from this thermal temperature is then used to create energy.

Several countries in the world, especially in Europe are experimenting with Incineration as an alternate means of energy production; Sweden, Germany and Luxembourg to name a few.

Thermal technologies:

Depolymerisation  and pyrolysis Often said to be a replication or representation of the conditions under which fossil fuels were created, Depolymerisation has its own sets of benefits and limitations.

Gasification is another developing process employed for waste to energy generation. Gasification converts carbonaceous substances into carbon dioxide, carbon mono oxide and some amount of hydrogen. Pyrolysis is another waste to energy process, used majorly in industrial processes.  Pyrolysis employs agricultural waste or organic waste from industries .Plasma arc gasification as the name suggests uses plasma technologies to obtain syngas or synthesis gas. A plasma torch is used to ionize gas and there after obtain synthesis gas. The process generates electricity while compressing the waste.

Non-thermal technologies:

Fermentation is also being developed as a form of management. Waste to energy is an emerging innovative set of technologies aimed at better sustenance of the environment, with minimum damage to the ecosystems. With these technologies developing by day and their acceptance increasing amongst households and industrial set-ups worldwide, waste to energy is seen as a development tool for emerging countries. The MBT technology stands for Mechanical Biological treatment. The technology uses domestic waste as well as industrial and commercial waste to generate products.

hazardous-waste management, the collection, treatment, and disposal of waste material that, when improperly handled, can cause substantial harm to human health and safety or to the environment. Hazardous wastes can take the form of solids, liquids, sludge’s, or contained gases, and they are generated primarily by chemical production, manufacturing, and other industrial activities. They may cause damage during inadequate storage, transportation, treatment, or disposal operations. Improper hazardous-waste storage or disposal frequently contaminates surface and groundwater supplies. People living in homes built near old and abandoned waste disposal sites may be in a particularly vulnerable position. In an effort to remedy existing problems and to prevent future harm from hazardous wastes, governments closely regulate the practice of hazardous-waste management. Proper treatment, storage and disposal are required.

 There are eight major groups of waste management methods, each of them divided into numerous categories. Those groups include source reduction and reuse, animal feeding, recycling, composting, fermentation, landfills, incineration and land application. You can start using many techniques right at home, like reduction and reuse, which works to reduce the amount of disposable material used.

Methods of Waste Disposal

·        Landfill

·        The Landfill is the most popularly used method of waste disposal used today. This process of waste disposal focuses attention on burying the waste in the land

·        Incineration/Combustion

·        Incineration or combustion is a type disposal method in which municipal solid wastes are burned at high temperatures so as to convert them into residue and gaseous products. .

·        Recovery and Recycling

·        Resource recovery is the process of taking useful discarded items for a specific next use. These discarded items are then processed to extract or recover materials and resources or convert them to energy in the form of useable heat, electricity or fuel.

·        Recycling is the process of converting waste products into new products to prevent energy usage and consumption of fresh raw materials. Recycling is the third component of Reduce, Reuse and Recycle waste hierarchy. The idea behind recycling is to reduce energy usage, reduce volume of landfills, reduce air and water pollution, reduce greenhouse gas emissions and preserve natural resources for future use.

·        Plasma gasification

Plasma gasification is another form of waste management. Plasma is a primarily an electrically charged or a highly ionized gas. Lighting is one type of plasma which produces temperatures that exceed 12,600 °F . With this method of waste disposal, a vessel uses characteristic plasma torches operating at +10,000 °F which is  creating a gasification zone till 3,000 °F for the conversion of solid or liquid wastes into a syngas

As the world population produces more and more trash, it is high time to examine the evolution of the waste management and recycling business and the use of robotics in managing this recoverable waste stream. The effective use of such smart technology is regarded as a major step forward in managing and recycling waste. Americans alone are responsible for producing a hopping 220 million tons of waste a year. This number is far more than any other nation in the world .Because of this fact both the government and environmental associations have developed numerous methods of dealing with the problem. Waste management is that solution, a rather complex issue that encompasses more than 20 different industries. Waste management is collection, transportation, and disposal of garbage, sewage and other waste products. Waste management is the process of treating solid wastes and offers variety of solutions for recycling items that don’t belong to trash. It is about how garbage can be used as a valuable resource. Waste management is something that each and every household and business owner in the world needs.

Flexible treatment of petrochemical and oil waste disposal:

Treatment of petrochemical wastes using  plasma technology offers commercial advantage over existing waste management options whilst reducing landfill liabilities and ensuring the conservation of natural resources. It offers a clean and cost effective solution for oil waste disposal and petrochemical waste management.

Plasma principal advantages in petrochemical and sludge treatment disposal include:

Oily Sludges generated during oil tank cleaning operations are as follows:

·        Hazardous Waste Streams Contaminated with Heavy Metals and Persistent Organic Pollutants (POPs; e.g. PCBs and HCBs)

·        Secondary residues from alternative treatment processes

·        Naturally Occurring Radioactive Materials (NORM)

·        Acid tars generated from benzole refining, oil re-refining and white oil production

Process: The heat and ultra-violet light properties of plasma technology treats contaminated petrochemical waste materials so that the pollutant is destroyed and the bulk mass material is recovered as a safe, inert building product, so completing the sustainability cycle.

HOW TO RECYCLE YOUR PRINTER

Used printers and printer cartridges have a major impact on landfill space and the environment. More than 350 million used printer cartridges end up in landfills every year. A woeful 70% of printer cartridges aren’t recycled although they can be remanufactured three to four times before they actually wear out. The heavy metals in printers account for much of the lead, cadmium, copper, and chromium found in landfills. It takes 450 to 1,000 years for printer cartridge waste to break down. Recycling a used printer cartridge saves energy, water, and keeps trash out of the landfill. Recycling a printer cartridge saves almost a gallon of oil (the amount of oil needed to manufacture a new printer cartridge), avoids water contamination caused by leeching of heavy metals into the soil, and keeps about two pounds of waste out of the landfill. Discarded printer cartridges add 400,000 tons of waste to landfills every year. A company can dramatically reduce their carbon footprint by recycling printers and printer cartridges. An electronics recycling company will normally sell used but working printers on the grey market because the printer has value above its scrap value. Used printer cartridges will be remanufactured and sold or sold to other companies that remanufacture printer cartridges. Printers and printer cartridges that have reached the end of their life are scrapped for their metals and plastic content. Printer cartridges have both precious metal and copper components. Printers have steel and copper as well, but they are also home to toxic metals such as lead, cadmium, and chromium. That is another important reason these electronic devices should be sent to All Green Recycling.

Disposal of Photographic Chemicals and Film

No photo chemicals with a pH of less than or equal to 2 or greater than or equal to 12.5 can be disposed of down the drain.

Spent Developer (alkaline) and Spent Stop Bath (acidic): may be combined in a single container (with good ventilation) to neutralize the solutions (pH ~7) and make them nonhazardous. Then the combined solution can be disposed of down the sink.

Fixers, toners, reducers or intensifiers: cannot be placed untreated down the sink because they contain silver and other heavy metals. These chemicals should be combined into one container and labelled as Hazardous Waste. Dispose of through EH&S using the online Chemical Waste Pickup Request Form.

Darkrooms which have a silver recovery unit installed must ensure that all spent fixer flows through the silver recovery unit, rendering the solution non-hazardous; the fixer solution may then be disposed of down the drain. Individuals using darkrooms which do not have a silver recovery unit should contact EH&S at 392-8400 to determine whether or not a unit can be installed for this purpose.

All unused, concentrated photographic materials: must be handled by EH&S as a hazardous waste.

Photographic film: must be recycled through EH&S.

Many councils now collect food waste, which can be recycled in several ways including: In-vessel composting involves mixing food waste with garden waste – shredding it and then composting it in an enclosed system for around 2-4 weeks (temperatures of up to 70°C speed up the process and ensure any harmful microbes are killed off. The material is then left outside to mature for a further 1-3 months with regular turning and checks to ensure quality before going on to be used as soil conditioner. Reducing food waste is a major issue and not just about good food going to waste; wasting food costs the average family with children almost £60 a month and has serious environmental implications too .The amount of food we throw away is a waste of resources. Just think about all the energy, water and packaging used in food production, transportation and storage. This all goes to waste when we throw away perfectly good food. Cheese is a good example – feeding and milking the cows, cooling and transporting the milk, processing it in to cheese, packing it, getting it to the shops, keeping it at the right temperature all the time. If it then gets thrown away it will most likely end up in a landfill site, where, rather than harmlessly decomposing as many people think, it rots and actually releases methane, a powerful greenhouse gas.

We’ve long ago learned the motto: Recycle, Reduce, and Reuse. And it’s easy to apply on a personal level. Industrial waste recycling includes chemical waste, e-waste, metal waste, plastic waste, paper recycling, rubber recycling etc.  Many industrial processes have the potential to produce hazardous waste. To help potential hazardous waste generators identify if they produce hazardous waste, it provides examples of hazardous wastes that are typically generated by specific industries and provide suggestions for how to recycle, treat or dispose of the wastes according to federal regulations. The most important benefit of industrial recycling is the fact that you are putting less strain on the Earth’s resources by finding ways to reuse or recycle industrial waste. When industrial waste materials and by-products are reused, it decreases the need to produce new raw materials. Less waste also lessens our need for landfills, allowing that land to be used for other purposes, and reduces the greenhouse emissions and other gas pollutants that originate as waste in landfills breaks down. Additionally, you can also reduce costs by purchasing raw materials made from recycled materials. Aluminium, for example, is one of the fastest and easiest materials to recycle and is used in numerous manufacturing industries. But you’re paying almost twice as much when you purchase fresh aluminium over recycled aluminium.

Introduction to Wastewater Treatment Processes

Wastewater treatment is closely related to the standards and/or expectations set for the effluent quality. Wastewater treatment processes are designed to achieve improvements in the quality of the wastewater. The various treatment processes may reduce:

·        Suspended solids (physical particles that can clog rivers or channels as they settle under gravity)

·        Biodegradable organics (e.g. BOD) which can serve as “food” for microorganisms in the receiving body.

·        Pathogenic bacteria and other disease causing organisms These are most relevant where the receiving water is used for drinking, or where people would otherwise be in close contact with it; and

·        Nutrients, including nitrates and phosphates. Widely used terminology refers to three levels of wastewater treatment: primary, secondary, and tertiary (or advanced).

·        Primary (mechanical) treatment is designed to remove gross, suspended and floating solids from raw sewage. It includes screening to trap solid objects and sedimentation by gravity to remove suspended solids. This level is sometimes referred to as “mechanical treatment”, although chemicals are often used to accelerate the sedimentation process.

·        Secondary (biological) treatment removes the dissolved organic matter that escapes primary treatment. This is achieved by microbes consuming the organic matter as food, and converting it to carbon dioxide, water, and energy for their own growth and reproduction. The biological process is then followed by additional settling tanks (“secondary sedimentation", see photo) to remove more of the suspended solids.

·        Tertiary treatment is simply additional treatment beyond secondary! Tertiary treatment can remove more than 99 per cent of all the impurities from sewage, producing an effluent of almost drinking-water quality.

Each year, approximately 100 million tires are processed by the recycling industry. In the past, scrap tires — generated when an old, worn tire is replaced with a new tire — were often dumped illegally in lakes, abandoned lots, along the side of the road and in sensitive habitats. At tire recycling facilities, the main piece of equipment is the tire shredder, which uses powerful, interlocking knives to chop tires into smaller pieces. Shredding a tire at room temperature using such knives is called ambient shredding. Tires can also be shredded through a cryogenic process that uses liquid nitrogen to freeze them at a sub-zero temperature. Such temperatures cause the physical properties of the tires to change dramatically and become very brittle. The tire is placed in an enclosure in which powerful hammers smash the tire apart. Cryogenic grinding is used to make fine crumb rubber powders that are then used in products such as synthetic turf. The non-rubber portions of the tire also are recycled. For example, the steel beads that give the tire its shape and structure are recovered by recyclers and processed into specification grade product used by steel mills for the production of new steel. The future for tire recycling is strong. Applications for scrap tire rubber — such as rubberized asphalt—have become recognized for their preferable properties and is gaining in prominence and widespread use. Many states already use rubberized asphalt when they design, reconstruct or repair their roadways and it is used for several simple and straightforward reasons: it can cost less, provide safety benefits and last longer than conventional asphalt.

Plastic is among the most popular and important materials used in the modern world. However, its popularity is part of the huge problem and reason why plastics should be recycled. Instead of throwing them away polluting the land and our water bodies, we can optimize the lifespan of plastics by recycling and reusing them.

Plastic recycling refers to the process of recovering waste or scrap plastic and reprocessing it into useful product. Due to the fact that plastic is non-biodegradable, it is essential that it is recycled as part of the global efforts to reducing plastic and other solid waste in the environment. The following is a step by step process of plastic recycling:1) collection, 2)sorting, 3)shredding, 4)cleaning,5)melting.

After the melting process, the plastic pieces are then compressed into tiny pellets known as nurdles. In this state, the plastic pellets are ready for reuse or be redesigned into new plastic products. It is important to point out that recycled plastic is hardly used to make identical plastic item or its previous form. It is in this pellet form that plastics are transported to plastic manufacturing companies to be redesigned and be used in making other useful plastic products.

 E-waste is electrical and electronic equipment of any kind that has been discarded. Recycling e-waste protects human and environmental health. Improper disposal of e-waste leads to environmental pollution and this may in turn harm human health. The best way to treat e-waste is to recycle it properly. E-waste comprises many different components and requires specialised equipment to dismantle, shred, process and extract the constituent materials that can then be turned into new products. This has to be performed within a controlled system to prevent pollution and ensure workplace safety and health. Recycling e-waste also helps to conserves our earth’s precious natural resources. Recycled material is used to make new products. This reduces the need to mine virgin raw materials from the earth, which are limited in supply. Reducing the need for mining also lowers pollution, as the process of mining has an impact on our environment. Common types of e-waste includes mobile phones, computer and mobile phone batteries, Home appliances, such as TVs, fridges, air conditioners, washing machines, lamps & lighting, electronic toys etc.

The vegetable oil before being discarded should be sent for recycling so that it can be recycled as bio diesel or other household purposes. It is always better to recycle your cooking oil and grease then put it into your sink. Cooking oils and grease can cause your sewers to backup which could damage your home or threaten the environment. vegetable oil refining is a process to transform vegetable oil into fuel by hydrocracking or hydrogenation. Hydrocracking breaks larger molecules into smaller ones using hydrogen while hydrogenation adds hydrogen to molecules. These methods can be used for production of gasoline, diesel, and propane. The diesel fuel that is produced has various names including green diesel or renewable diesel .In the past waste oils were collected by pig farmers as part of food waste from pig swill bins. The grease was skimmed off the swill tanks and sold for further processing, while the remaining swill was processed into pig food.

To avoid the potential risks associated with chemical wastes, it is important that people always monitor the use, storage, and disposal of products with potentially hazardous substances in their homes. Improper disposal of HHW can include pouring them down the drain, on the ground, into storm sewers, or in some cases putting them out with the regular trash.

The dangers of such disposal methods might not be immediately obvious, but improper disposal of these wastes can pollute the environment and pose a threat to human health. Certain types of chemical wastes have the potential to cause physical injury to sanitation workers, contaminate septic tanks or wastewater treatment systems if poured down drains or toilets. They can also present hazards to children and pets if left around the house.