Biogas from Slaughterhouse Wastes

Slaughterhouse waste (or abattoir waste) disposal has been a major environmental challenge in all parts of the world. The chemical properties of slaughterhouse wastes are similar to that of municipal sewage, however the former is highly concentrated wastewater with 45% soluble and 55% suspended organic composition. Blood has a very high COD of around 375,000 mg/L and is one of the major dissolved pollutants in slaughterhouse wastewater.

slaughterhouse-waste

In most of the developing countries, there is no organized strategy for disposal of solid as well as liquid wastes generated in abattoirs. The solid slaughterhouse waste is collected and dumped in landfills or open areas while the liquid waste is sent to municipal sewerage system or water bodies, thus endangering public health as well as terrestrial and aquatic life. Wastewater from slaughterhouses is known to cause an increase in the BOD, COD, total solids, pH, temperature and turbidity, and may even cause deoxygenation of water bodies.

Anaerobic Digestion of Slaughterhouse Wastes

There are several methods for beneficial use of slaughterhouse wastes including biogas generation, fertilizer production and utilization as animal feed. Anaerobic digestion is one of the best options for slaughterhouse waste management which will lead to production of energy-rich biogas, reduction in GHGs emissions and effective pollution control in abattoirs.

Anaerobic digestion can achieve a high degree of COD and BOD removal from slaughterhouse effluent at a significantly lower cost than comparable aerobic systems. The biogas potential of slaughterhouse waste is higher than animal manure, and reported to be in the range of 120-160 m3 biogas per ton of wastes. However the C:N ratio of slaughterhouse waste is quite low (4:1) which demands its co-digestion with high C:N substrates like animal manure, food waste, crop residues, poultry litter etc.

Slaughterhouse effluent has high COD, high BOD, and high moisture content which make it well-suited to anaerobic digestion process. Slaughterhouse wastewater also contains high concentrations of suspended organic solids including pieces of fat, grease, hair, feathers, manure, grit, and undigested feed which will contribute the slowly biodegradable of organic matter. Amongst anaerobic treatment processes, the up-flow anaerobic sludge blanket (UASB) process is widely used in developing countries for biogas production from abattoir wastes.

Slaughterhouse waste is a protein-rich substrate and may result in sulfide formation during anaerobic degradation. The increased concentration of sulfides in the digester can lead to higher concentrations of hydrogen sulfide in the biogas which may inhibit methanogens. In addition to sulfides, ammonia is also formed during the anaerobic digestion process which may increase the pH in the digester (>8.0) which can be growth limiting for some VFA-consuming methanogens.

Transforming Waste to Energy: The Electrician’s Role

Let’s imagine a world where waste does not end up in landfills. Instead, a world where every piece of discarded item becomes a valuable resource that generates energy. This is not just a dream, but also a rapidly developing field of sustainable development known as waste-to-energy transformation.

The role of an electrician in this transformative process cannot be overestimated. Their skills and understanding of the underlying principles guide the successful transformation and harnessing of energy from trash.

role of electrician in WTE plant

Understanding Waste-to-Energy Conversion

Primarily, it’s crucial to understand the workings of waste-to-energy conversion. As inferred from the terminology, this process involves repurposing waste materials – spanning from household scraps to industrial residues – into electricity, heat or fuel.

The methodologies adopted entail diverse techniques, yet their core objective remains consistent: to cut down greenhouse gas emissions while concurrently producing beneficial energy.

Electrician’s Role: Critical Overview

Now let’s consider how a local electrician in Liverpool features into this equation. For starters, waste-to-energy plants require sophisticated electrical systems to manage the complex processes involved in converting waste into power—everything from initial intake to combustion or biological conversion then onto generating electricity with steam turbines or internal combustion engines.

Entities specialized in turning waste materials into renewable energy highly value the crucial hands-on skills and technical knowhow of professionals – recognizing them as key actors in ensuring that these cutting-edge facilities function effectively day in and day out.

Tech Skills Required by Electricians

In particular, electricians’ tasks often encompass installation, maintenance, inspection and repair of the electrical components these systems have. Henceforth they need professional abilities beyond average household wiring jobs like designing and implementing specialized electrical circuits supportive for high-powered industrial machinery.

Indeed, their responsibilities may also intertwine with an understanding of computer control systems provided modern waste management equipment often comes with computer-aided operation enabled.

Importance of Environmental Impact Awareness

Moreover their significant roles don’t simply halt at technicalities alone nonetheless extend towards contributing positively towards environmental conservation efforts too . Being part of this revolutionary industry can affect electricians’ perception about electrical efficiency promoting practices which consequently deliver broader societal benefits.

Hence their occupation is more than just another job; it empowers them with the capability to make measurable positive influence on the world. Each time they step on-site – armed with skills and environmental consciousness – they take an active stance against climate change.

Case Studies: Electricians’ Contributions

There have been numerous proprietary instances illustrating how these specialists helped enable sustainable practices . One such impressive example came to light within Alberta Canada; wherein local electricians partnered with Enerkem, a biofuels producer, creating one of the first full-scale municipal solid waste-to-biofuel facilities worldwide .

Similarly Denmark – prominently recognized for its dedication toward sustainability – observed its local electricians’ substantial contributions ensuring successful operations regarding Amager Bakke, Copenhagen-based hi-tech waste-to-energy plant considered a futuristic marvel that skis atop its green roof function .

Sysav–WTE-plant-Sweden

Sweden is one of the best proponents of waste-to-energy in the world

Future Prospects: Waste to Energy

Witnessing such case studies illustrates the immense possibilities latent within this promising sector. Present observations merely skim the surface, barely hinting at the vast dormant potential beneath. If you’re considering embarking on a career as an electrician, this realm can be particularly lucrative.

However, even for those already nestled in this field, taking up proactive roles to shape our upcoming sustainable future could not only solidify your position but potentially make you a trendsetter spearheading the environmental revolution.

Accelerating Green Trends: Electricians’ Spotlight

Amid the world speeding up green initiatives, electricians can shine bright like a beacon, lighting our path and accelerating progression towards waste-to-energy practices. They play a key role in catalyzing a chain of transformation, which comprehensively explores sustainable energy options while producing significantly less waste.

Their cutting-edge expertise, combined with their proactive stewardship, sets them apart as vanguards in this stimulating era of ecological evolution. The discovery and adoption of creative solutions for transforming waste have amplified their importance within our daily lives. More than ever, they’re appreciated – not merely for keeping our homes powered but also for relentlessly fuelling innovations that make significant strides towards environmental preservation.

Harnessing the Power of Waste: The Road Forward

The continuous exploration and application of waste-to-energy mechanisms demonstrate a future where conservation isn’t solely about restriction, but also about innovative utilization. And herein lies the genuine value of being actively involved in this field.

Final Thoughts

As we forge ahead into the tumultuous frontiers of the 21st century, meeting the daunting challenge of climate change head-on demands astutely leveraging every resource at our disposal. In this crucial mission, tradespeople with specialized knowledge bear gifted potential to significantly steer our progress towards a greener planet.

Electricians hold a cardinal role in this context of environmental regeneration. They bridge the gap between the burgeoning field of waste-to-energy conversion and real-life application. Beyond just technical operators, they are inadvertent harbingers of sustainability, contributing constructively to counter mounting environmental concerns.

The Energy Potential of Palm Kernel Shells

The Palm Oil industry in Southeast Asia and Africa generates large quantity of biomass wastes whose disposal is a challenging task. Palm kernel shells (or PKS) are the shell fractions left after the nut has been removed after crushing in the Palm Oil mill. Kernel shells are a fibrous material and can be easily handled in bulk directly from the product line to the end use. Large and small shell fractions are mixed with dust-like fractions and small fibres. Moisture content in kernel shells is low compared to other biomass residues with different sources suggesting values between 11% and 13%.

palm-kernel-shells

Palm kernel shells contain residues of Palm Oil, which accounts for its slightly higher heating value than average lignocellulosic biomass. Compared to other residues from the industry, it is a good quality biomass fuel with uniform size distribution, easy handling, easy crushing, and limited biological activity due to low moisture content. PKS can be readily co-fired with coal in grate fired -and fluidized bed boilers as well as cement kilns in order to diversify the fuel mix.

The primary use of palm kernel shells is as a boiler fuel supplementing the fibre which is used as primary fuel. In recent years kernel shells are sold as alternative fuel around the world. Besides selling shells in bulk, there are companies that produce fuel briquettes from shells which may include partial carbonisation of the material to improve the combustion characteristics.

As a raw material for fuel briquettes, palm shells are reported to have the same calorific characteristics as coconut shells. The relatively smaller size makes it easier to carbonise for mass production, and its resulting palm shell charcoal can be pressed into a heat efficient biomass briquette.

Palm kernel shells have been traditionally used as solid fuels for steam boilers in palm oil mills across Southeast Asia. The steam generated is used to run turbines for electricity production. These two solid fuels alone are able to generate more than enough energy to meet the energy demands of a palm oil mill. Most palm oil mills in the region are self-sufficient in terms of energy by making use of kernel shells and mesocarp fibers in cogeneration.

In recent years, the demand for palm kernel shells has increased considerably in Europe, Asia-Pacific, China etc. resulting in price close to that of coal. Nowadays, cement industries and power producers are increasingly using palm kernel shells to replace coal. In grate-fired boiler systems, fluidized-bed boiler systems and cement kilns, palm kernel shells are an excellent fuel.

Cofiring of PKS yields added value for power plants and cement kilns, because the fuel significantly reduces carbon emissions – this added value can be expressed in the form of renewable energy certificates, carbon credits, etc. However, there is a great scope for introduction of high-efficiency cogeneration systems in the industry which will result in substantial supply of excess power to the public grid and supply of surplus PKS to other nations. Palm kernel shell is already extensively in demand domestically by local industries for meeting process heating requirements, thus creating supply shortages in the market.

Palm oil mills around the world may seize an opportunity to supply electricity for its surrounding plantation areas using palm kernel shells, empty fruit branches and palm oil mill effluent which have not been fully exploited yet. This new business will be beneficial for all parties, increase the profitability and sustainability for palm oil industry, reduce greenhouse gas emissions and increase the electrification ratio in surrounding plantation regions.

Thermal Conversion of Tannery Wastes

Tanneries generate considerable quantities of sludge, shavings, trimmings, hair, buffing dusts and other general wastes and can consist of up to 70% of hide weight processed. Thermal conversion technologies by virtue of chemically reducing conditions, provides a viable alternative thermal treatment for tannery wastes, especially for chrome containing materials, and generates a chrome (III) containing ash. This ash has significant commercial value as it can be reconstituted.

tannery-wastes

All of the wastes generated by the tannery can be gasified following pre-treatment methods such as maceration, drying and subsequent densification or briquetting. A combined drying and gasification process could eliminate solid waste, whilst providing a combustible gas as a tax-exempt renewable energy source, which the tannery can directly reuse. Gasification trials have illustrated that up to 70% of the intrinsic energy value of the wastes currently disposed can be recovered as “synthesis gas” energy.

Gasification technology has the potential to provide significant cost benefits in terms of power generation and waste disposal, and increase sustainability within the leather industry. The gasification process converts any carbon-containing material into a combustible gas comprised primarily of carbon monoxide, hydrogen and methane, which can be used as a fuel to generate electricity and heat.

A wide range of tannery wastes can be macerated, flash dried, densified and gasified to generate a clean syngas for reuse in boilers or other Combined Heat and Power systems. As a result up to 70% of the intrinsic energy value of the waste can be recovered as syngas, with up to 60% of this being surplus to process drying requirements so can be recovered for on-site boiler or thermal energy recovery uses.

A proprietary technology has been in commercial operation at a tanyard on the West Coast of Norway since mid 2001. The process employs gasification-and-plasma-cracking and offer the capability of turning the tannery waste problem to a valorising source that may add values to the plant owner in terms of excessive energy and ferrochrome, a harmless alloy that is widely used by the metallurgical industry. The process leaves no ashes but a non-leaching slag that is useful for civil engineering works, and, hence, no residues for landfill disposal

Use of Sewage Sludge in Cement Industry

Cities around the world produce huge quantity of municipal wastewater (or sewage) which represents a serious problem due to its high treatment costs and risk to environment, human health and marine life. Sewage generation is bound to increase at rapid rates due to increase in number and size of urban habitats and growing industrialization.

sewage_sludge

An attractive disposal method for sewage sludge is to use it as alternative fuel source in cement industry. The resultant ash is incorporated in the cement matrix. Infact, several European countries, like Germany and Switzerland, have already started adopting this practice for sewage sludge management. Sewage sludge has relatively high net calorific value of 10-20 MJ/kg as well as lower carbon dioxide emissions factor compared to coal when treated in a cement kiln.

Use of sludge in cement kilns can also tackle the problem of safe and eco-friendly disposal of sewage sludge. The cement industry accounts for almost 5 percent of anthropogenic CO2 emissions worldwide. Treating municipal wastes in cement kilns can reduce industry’s reliance on fossil fuels and decrease greenhouse gas emissions.

The use of sewage sludge as alternative fuel in clinker production is one of the most sustainable option for sludge waste management. Due to the high temperature in the kiln the organic content of the sewage sludge will be completely destroyed. The sludge minerals will be bound in the clinker after the burning process. The calorific value of sewage sludge depends on the organic content and on the moisture content of the sludge. Dried sewage sludge with high organic content possesses a high calorific value.  Waste coming out of sewage sludge treatment processes has a minor role as raw material substitute, due to their chemical composition.

The dried municipal sewage sludge has organic material content (ca. 40 – 45 wt %), therefore the use of this alternative fuel in clinker production will save fossil CO2 emissions. According to IPCC default of solid biomass fuel, the dried sewage sludge CO2 emission factor is 110 kg CO2/GJ without consideration of biogenic content. The usage of municipal sewage sludge as fuel supports the saving of fossil fuel emission.

Sludge is usually treated before disposal to reduce water content, fermentation propensity and pathogens by making use of treatment processes like thickening, dewatering, stabilisation, disinfection and thermal drying. The sludge may undergo one or several treatments resulting in a dry solid alternative fuel of a low to medium energy content that can be used in cement industry.

The use of sewage sludge as alternative fuel is a common practice in cement plants around the world, Europe in particular. It could be an attractive business proposition for wastewater treatment plant operators and cement industry to work together to tackle the problem of sewage sludge disposal, and high energy requirements and GHGs emissions from the cement industry.

Biofuels from MSW – An Introduction

Nowadays, biofuels are in high demand for transportation, industrial heating and electricity generation. Different technologies are being tested for using MSW as feedstock for producing biofuels. This article will provide brief description of biochemical and thermochemical conversion routes for the production of biofuels from municipal solid wastes.

drop-in-biofuels

Biochemical conversion

The waste is collected and milled, particles are shredded to reduce the size of 0.2-1.22 mm. MSW is pretreated to improve the accessibility of enzymes and make use of the enzymes in the bacteria for biological degradation on solid waste. The mixture of biomass is mixed with sulfuric acid and sodium hydroxide and autoclaved. After steam treatment, the mixture is filtered and washed with deionized water. The pre-treated mixture is then dried and drained overnight. The pre-treatment process improves the formation of sugars by enzymatic hydrolysis, avoids the loss of carbohydrate and avoids the formation of by-products inhibitory.

After pre-treatment (pre-hydrolysis), the mixture undergoes enzymatic hydrolysis for conversion of polysaccharides into monomer sugars, such as glucose and xylose. The common enzymes used for starch-based substrates are amylase, pullulanase, isomylase and glucoamylase. Whereas for lignocellulose based substrates cellulases and glucosidases.

Finally, the mixture is fermented; sugars are converted to ethanol by using microorganisms such as, bacteria, yeast or fungi. The cellulosic and starch hydrolysates ethanolic fermentation were fermented by M. indicus at 37 °C for 72 h. The fungus uses the hexoses and pentoses sugars with a high concentration of inhibitors (i.e. furfural, hydroxymethyl furfural, and acetic acid).

The composition of MSW feedstock effects the yield of the subsequent processes. A high composition of food and vegetable waste is more desirable, as these wastes are easily degradable and result in high yields compared to paper and cardboard.

Thermochemical conversion

Gasification process is carried out by treating carbon-based material with either oxygen or steam to produce a gaseous fuel which requires high temperature and pressure. It can be described as partial oxidation of the waste. At first waste is reduced in size and dried to reduce the amount of energy used in the gasifier.

Biomass_Gasification_Process

Layout of a Typical Biomass Gasification Plant

 

The carbonaceous material oxidizes (combines with oxygen) to produce syngas (carbon monoxide and hydrogen) along with carbon dioxide, methane, water vapor, char, slag, and trace gases (depending on the composition of the feedstock). The syngas is then cleaned to remove any sulfur or acid gases and trace metals (depending on the composition of the feedstock).

The main uses of syngas are direct burning on site to provide heat or energy (by using boilers, gas turbines or steam driven engines) and refined to liquid fuels such as gasoline or ethanol.

Syngas can then be converted into biofuels and chemicals via catalytic processes such as the Fischer-Tropsch process. The Fischer-Tropsch process is a series of catalytic chemical reactions that convert syngas into liquid hydrocarbons by applying heat and pressure. Hydrocracking, hydro-treating, and hydro-isomerization can also be part of the “upgrading” process to maximize quantities of different products.

Waste Management in Qatar

Waste management is one of the most serious environmental challenges faced by the tiny Gulf nation of Qatar. mainly on account of high population growth rate, urbanization, industrial growth and economic expansion. The country has one of the highest per capita waste generation rates worldwide of 1.8 kg per day.

Qatar produces more than 2.5 million tons of municipal solid waste each year. Solid waste stream is mainly comprised of organic materials (around 60 percent) while the rest of the waste steam is made up of recyclables like glass, paper, metals and plastics.

landfill-qatar

Municipalities are responsible for solid waste collection in Qatar both directly, using their own logistics, and indirectly through private sector contract. Waste collection and transport is carried out by a large fleet of trucks that collect MSW from thousands of collection points scattered across the country.

The predominant method of solid waste disposal in Qatar is landfilling. The collected is discharged at various transfer stations from where it is sent to the landfill. There are three landfills in Qatar; Umm Al-Afai for bulky and domestic waste, Rawda Rashed for construction and demolition waste, and Al-Krana for sewage wastes. However, the method of waste disposal by landfill is not a practical solution for a country like Qatar where land availability is limited.

Solid Waste Management Strategy

According to Qatar National Development Strategy 2011-2016, the country will adopt a multi-faceted strategy to contain the levels of waste generated by households, commercial sites and industry – and to promote recycling initiatives. Qatar intends to adopt integrated waste hierarchy of prevention, reduction, reuse, recycling, energy recovery, and as a last option, landfill disposal.

A comprehensive solid waste management plan is being implemented which will coordinate responsibilities, activities and planning for managing wastes from households, industry and commercial establishments, and construction industry. The target is to recycle 38 percent of solid waste, up from the current 8 percent, and reduce domestic per capita waste generation.

Five waste transfer stations have been setup in South Doha, West Doha, Industrial Area, Dukhan and Al-Khor to reduce the quantity of waste going to Umm Al-Afai landfill. These transfer stations are equipped with material recovery facility for separating recyclables such as glass, paper, aluminium and plastic.

Domestic Solid Waste Management Centre

One of the most promising developments has been the creation of Domestic Solid Waste Management Centre (DSWMC) at Mesaieed. This centre is designed to maximize recovery of resources and energy from waste by installing state-of-the-art technologies for separation, pre-processing, mechanical and organic recycling, and waste-to-energy and composting technologies.

At its full capacity, it treats 1550 tons of waste per day, and is expected to generate enough power for in-house requirements, and supply a surplus of 34.4 MW to the national grid.

Future Outlook

While commendable steps are being undertaken to handle solid waste, the Government should also strive to enforce strict waste management legislation and create mass awareness about 4Rs of waste management viz. Reduce, Reuse, Recycle and Recovery. Legislation are necessary to ensure compliance, failure of which will attract a penalty with spot checks by the Government body entrusted with its implementation.

Improvement in curbside collection mechanism and establishment of material recovery facilities and recycling centres may also encourage public participation in waste management initiatives. When the Qatar National Development Strategy 2011-2016 was conceived, the solid waste management facility plant at Mesaieed was a laudable solution, but its capacity has been overwhelmed by the time the project was completed. Qatar needs a handful of such centers to tackle the burgeoning garbage disposal problem.

Everything You Should Know About MSW-to-Energy

You know the saying: One person’s trash is another’s treasure. When it comes to recovering energy from municipal solid waste — commonly called garbage or trash— that treasure can be especially useful. Instead of taking up space in a landfill, we can process our trash to produce energy to power our homes, businesses and public buildings.

In 2015, the United States got about 14 billion kilowatt-hours of electricity from burning municipal solid waste, or MSW. Seventy-one waste-to-energy plants and four additional power plants burned around 29 million tons of MSW in the U.S. that year. However, just 13 percent of the country’s waste becomes energy. Around 35 percent is recycled or composted, and the rest ends up in landfills.

MSW-to-Energy

Recovering Energy Through Incineration

The predominant technology for MSW-to-energy plants is incineration, which involves burning the trash at high temperatures. Similarly to how some facilities use coal or natural gas as fuel sources, power plants can also burn MSW as fuel to heat water, which creates steam, turns a turbine and produces electricity.

Several methods and technologies can play a role in burning trash to create electricity. The most common type of incineration plant is what’s called a mass-burn facility. These units burn the trash in one large chamber. The facility might sort the MSW before sending it to the combustion chamber to remove non-combustible materials and recyclables.

These mass-burn incineration systems use excess air to facilitate mixing, and ensure air gets to all the waste. Many of these units also burn the fuel on a sloped, moving grate to mix the waste even further. These steps are vital because solid waste is inconsistent, and its content varies. Some facilities also shred the MSW before moving it to the combustion chamber.

Gasification Plants

Another method for converting trash into electricity is gasification. This type of waste-to-energy plant doesn’t burn MSW directly, but instead uses it as feedstock for reactions that produce a fuel gas known as synthesis gas, or syngas. This gas typically contains carbon monoxide, carbon dioxide, methane, hydrogen and water vapor.

Approaches to gasification vary, but typically include high temperatures, high-pressure environments, very little oxygen and shredding MSW before the process begins. Common MSW gasification methods include:

  • Pyrolysis, which involves little to no oxygen, partial pressure and temperatures between approximately 600 and 800 degrees Celsius.
  • Air-fed systems, which use air instead of pure oxygen and temperatures between 800 and 1,800 degrees Celsius.
  • Plasma or plasma arc gasification, which uses plasma torches to increase temperatures to 2,000 to 2,800 degrees Celsius.

Syngas can be burned to create electricity, but it can also be a component in the production of transportation fuels, fertilizers and chemicals. Proponents of gasification report that it is a more efficient waste-to-energy method than incineration, and can produce around 1,000 kilowatt-hours of electricity from one ton of MSW. Incineration, on average, produces 550 kilowatt-hours.

Also Read: The Role of an Electrician in a Waste-to-Energy Plant

Challenges of MSW-to-Energy

Turning trash into energy seems like an ideal solution. We have a lot of trash to deal with, and we need to produce energy. MSW-to-energy plants solve both of those problems. However, a relatively small amount of waste becomes energy, especially in the U.S.

Typical layout of MSW-to-Energy Plant

This lack may be due largely to the upfront costs of building a waste-to-energy plant. It is much cheaper in the short term to send trash straight to a landfill. Some people believe these energy production processes are just too complicated and expensive. Gasification, especially, has a reputation for being too complex.

Environmental concerns also play a role, since burning waste can release greenhouse gases. Although modern technologies can make burning waste a cleaner process, its proponents still complain it is too dirty.

Despite these challenges, as trash piles up and we continue to look for new sources of energy, waste-to-energy plants may begin to play a more integral role in our energy production and waste management processes. If we handle it responsibly and efficiently, it could become a very viable solution to several of the issues our society faces.

How Can You Produce Your Own Biogas?

The idea of biogas is anything but new. People have been experimenting with making biogas for many generations. Biogas is made by converting organic waste into energy. It’s a huge win for the environment because it utilizes what is otherwise considered waste, but it’s a big win for pocketbooks too.

Organic waste includes the byproducts of human food production (think potato peels, carrot peels, the tops of turnips, etc) but it also includes manure. Any manure is fair game, think about cows, pigs, chickens, rabbits, goats — virtually any farm animal produces mounds of this each day.

This manure produces very high levels of methane gas which is horrible for the environment. By using this manure to create biogas, we remove the danger of creating heat-trapping gases in our atmosphere that raises the temperature of the entire planet. Using it for biogas production can also help to reduce global warming.

How Do We Produce Biogas?

Biogas is produced from the breakdown of organic waste in an environment that is void of oxygen. We call this environment anaerobic and the process is process is called anaerobic digestion. Two products are created from this process. One is digestate. Digestate can be used for fertilizer and even as livestock bedding.  The other product is biogas. Biogas can be used for heating, electricity production and as a clean vehicle fuel.

It’s essentially like composting all of the materials, but in an environment without oxygen and in the temperature range of around 35 to 40 degrees Celsius and pH of around 7. This is optimal to produce biogas. Biogas can be converted into an upgraded form of gas by removal of carbon dioxide that can be used like natural gas. It can be used as-is as an engine fuel. It can be used as fuel in a vehicle, sometimes without modification.

How Can You Produce Your Own Biogas?

Just imagine being on your own off-grid property, running a hundred head of cattle, growing your own food and canning it. You’ve got meat covered, your food is stocked and you are prepared for just about anything. But what about fuel? Imagine what a game-changer it could be if you were able to produce your own fuel from the waste from your cattle and your garden scraps or food residuals! You can!

The Biogas Digester makes it possible, and fairly easy, for you to start producing your own biogas. Buy a ready-made biodigester for around $700-$1000 dollars and start producing your own biogas to meet your fuel requirements. They are containers designed to do the work for you and help you collect the fruits of your composted and digested waste.

Build your own! China has approximately 30 million Biodigesters in use in its rural areas. Rural Chinese areas are far removed from cities that have gas stations. It simply isn’t accessible as it is in the US. Many rural people have learned to make their own biodigesters to fill their fuel needs.

offgrid-biodigester

You need a tank that is sealed with an access hole on one side for adding organic waste. You have another access to an outlet. That is where you collect the liquid run-off that can be used for fuel.

The bottom of the main unit is the digestion chamber. From that is an outlet where the digestate can be collected and used as fertilizer. The main chamber typically has a domed top to allow for the room that will be necessary for the expansion of the gases formed inside. By being sealed, the unit creates that all-important anaerobic environment.

Useful Links

A tank that demonstrates the size and simplicity of a tank that can be purchased and used in the backyard.

https://www.etsy.com/listing/705458580/portable-home-biogas?gpla=1&gao=1&

This is a very in-depth article with directions for creating your own biodigester from Science Direct – https://www.sciencedirect.com/topics/engineering/biogas-digester

Waste Management in Sweden: Perspectives

Sweden is considered as a global leader in sustainable waste management and in the reduction of per capita carbon footprint. The country consistently works to lower its greenhouse gas emissions, improve energy efficiency and increase public awareness. Over the past 10 years, Sweden developed methods of repurposing waste, so less than one percent of the total waste generated in the country makes it to landfills. To accomplish this, the country changed their perspective of garbage.

Increase Recycling

Recycling is a part of Swedish culture. Residents regularly sort recyclable materials and food scraps from other waste in their homes before disposal. This streamlines the recycling process and reduces the effort required to sort large volumes of waste at larger recycling centers. As another way to promote recycling, the Swedish government created legislation stating recycling centers must be within 1,000 feet of residential areas. Conveniently located facilities encourage citizens to properly dispose of their waste.

Repurpose Materials

Citizens are also encouraged to reuse or repurpose materials before recycling or disposing of them. Repurposing and reusing products requires less energy when compared to the recycling or waste disposal process. As Swedes use more repurposed products, they reduce the volume of new products they consume which are created from fresh materials. In turn, the country preserves more of its resources.

Invest in Waste to Energy

Over 50 percent of the waste generated in Sweden is burned in waste-to-energy facilities. The energy produced by these facilities heats homes across the country during the long winter months. Localized heating — known as district heating — has improved air quality throughout the nation. It’s easier and more economical to control the emissions from several locations as opposed to multiple, smaller non-point sources.

Another benefit of waste-to-energy facilities is that ash and other byproducts of the burning process can be used for road construction materials. As a whole, Sweden doesn’t create enough waste to fuel its waste to energy plants — the country imports waste from its neighbors to keep its facilities going.

In the early 1990’s, the Swedish government shifted the responsibility for waste management from cities to the industries producing materials which would eventually turn to waste. To promote burning waste for energy, the government provides tax incentives to companies which make more economically attractive.

Impact of Waste-to-Energy

Although Sweden has eliminated the volume of trash entering landfills, they have increased their environmental impacts in other ways. Waste-to-energy facilities are relatively clean in that most harmful byproducts are filtered out before entering the environment, though they still release carbon-dioxide and water as their primary outputs. On average, waste-to-energy plants generate nearly 20 percent more carbon-dioxide when compared to coal plants.

 

waste-management-sweden

Coal plants burn and release carbon which is otherwise sequestered in the ground and unable to react with the earth’s atmosphere. Waste-to-energy facilities consume and release carbon from products made of organic materials, which naturally release their carbon over time. The downside to this process is that it frees the carbon from these materials at a much faster rate than it would be naturally.

The reliance on the waste-to-energy process to generate heat and the tax incentives may lower Swedish motivation to recycle and reuse materials. The country already needs to import trash to keep their waste-to-energy plants running regularly. Another disadvantage of this process is the removal and destruction of finite materials from the environment.

Even though Sweden continues to make strides in lowering their environmental impact as a whole, they should reevaluate their reliance on waste to energy facilities.