Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Biogas originates from biogenic material and is a type of biofuel.
One type of biogas is produced by anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste and energy crops. This type of biogas comprises primarily methane and carbon dioxide. The other principal type of biogas is wood gas which is created by gasification of wood or other biomass. This type of biogas is comprised primarily of nitrogen, hydrogen, and carbon monoxide, with trace amounts of methane.
The gases methane, hydrogen and carbon monoxide can be combusted or oxidized with oxygen. Air contains 21 percent oxygen. This energy release allows biogas to be used as a fuel. Biogas can be used as a low-cost fuel in any country for any heating purpose, such as cooking. It can also be used in modern waste management facilities where it can be used to run any type of heat engine, to generate either mechanical or electrical power. Biogas can be compressed, much like natural gas, and used to power motor vehicles and in the UK for example is estimated to have the potential to replace around 17 percent of vehicle fuel.Biogas is a renewable fuel, so it qualifies for renewable energy subsidies in some parts of the world.
Another definition what is Biogas?
Biogas is generated when bacteria degrade biological material in the absence of oxygen, in a process known as anaerobic digestion. Since biogas is a mixture of methane (also known as marsh gas or natural gas, CH4) and carbon dioxide it is a renewable fuel produced from waste treatment. Anaerobic digestion is basically a simple process carried out in a number of steps that can use almost any organic material as a substrate - it occurs in digestive systems, marshes, rubbish dumps, septic tanks and the Arctic Tundra. Humans tend to make the process as complicated as possible by trying to improve on nature in complex machines but a simple approach is still possible, as I hope you see in some of the links below. As methane is very hard to compress I see its best use as for stationary fuel, rather than mobile fuel. It takes a lot of energy to compress the gas (this energy is usually just wasted), plus you have the hazard of high pressure. A variable volume storage (flexible bag or floating drum are the two main variants) is much easier and cheaper to arrange than high pressure cylinders, regulators and compressors.
Hot to Make BioGas and How to Use Them?
These how to make biogas from human waste. Human Waste as a Resource.
Treating human waste through Anaerobic Digestion is an incredibly ethical sanitation technology. Anaerobic Digestion occurs in biodigesters and produces a fuel (biogas), removes Biochemical Oxygen Demand (BOD) from sewage, conserves nutrients (especially nitrogen compounds) and most importantly reduces pathogens. Human waste damages the environment because it is loaded with BOD, nutrients, and anthropozoonotic diseases. This can cause a host of environmental problems that can lead to ecosystem collapse such as rendering a water body uninhabitable for many organisms. Untreated sewage causes algal blooms, red tide, and so called dead zones. Humans also suffer from untreated sewage (also called black water). Waterborne disease transmitted through human excrement is a leading cause of death worldwide, especially in the so-called developing world. Some diseases caused by untreated human sewage are Cholera, Typhoid fever, Paratyphoid fever, Salmonella, Dysentery, Gastroenteritis, Leptospirosis, Meningitis, Hepatitis, and various parasitic diseases.
The amount of biogas that can be yielded from human waste is limited in comparison with livestock manure and other feedstocks. Are stomachs are just too efficient! David House states in his excellent book that 1000 lbs of humans produces about 0.6 cubic meters of biogas (enough cooking fuel for about 1 to 2 persons). But that amount quickly adds up, please reference the internet for example projects especially in Rwanda, India and Thailand.
Untreated sewage, along with causing a prevalence of disease, developing countries are also disposing of valuable nutrients in places where fertilizers aren’t available. Biodigesters turn waste into a biofertilizer. There is also a major flaw in the sewage treatment systems of developed countries where enormous amounts of energy are used to aerate and treat sewage; Anaerobic Digestion treats sewage and also produces energy rather than consumes it. This article discusses considerations for human waste treatment and various options are outlined.
Important! Considerations
A handful of considerations need to be made for treating human waste. There are IMPORTANT disease related issues and some common physical considerations. The number 1 issue is handling human waste. Operators that handle human waste without any precautions will inevitably get sick. The waste handling process must consider the handlers. Ideally a waste treatment system will eliminate any direct handling by humans.
Typical biodigester effluent is NOT sterile. Anaerobic digestion creates a competitive environment where pathogens are out competed by non-infectious microorganisms and therefore are edged out in terms of populations. This means that pathogens are REDUCED, but not entirely eliminated. However, studies in thermophilic biodigesters (45-55 degrees C) have shown a much greater reduction of pathogens than in ambient temperature and lower temperature biodigesters (see biodigesters capable of controlling pathogens section). A waste treatment system needs to address the issue of disease during the process via pre or post treatment or the effluent needs to be disposed of accordingly.
One common consideration in designing biodigesters to fit into an already existing system is that usually human excrement is heavily diluted to facilitate movement. Toilet flushes consume large volumes of water (range from 1.3 to 2.5 gallons but about 2 gallons in the US) and designing a biodigester with for example a 30-day hydraulic retention time (HRT) for treating flushed waste requires a very large volume biodigester at a 2 gallon per flush dilution. There are biodigester designs, however, that can handle an HRT, or the amount of time a biodigester retains a waste, of only a few hours. These designs are sludge retaining reactors such as an Upflow Anaerobic Sludge Blanket (UASB) and even better performing Fixed Film Reactors. One last important factor to consider is ammonia toxicity as human waste has been reported to have a low C: N ratio. This problem can be solved via dilution and co-digestion of a carbon rich feedstock such as molasses. Animal waste is inherently safer to treat then human waste because they tend to carry less human pathogens, though consideration for some manure born pathogens ought to be made as well.
Treatment Methods: Heat Pre-treatment
During this process human excrement would be pasteurized to 70 degrees C before entering the biodigester. This would be done best before dilution to reduce energy costs and can be done using waste steam, passive solar heating, or direct combustion of biogas or any other fuel source. The process would make more of the human excrement available for Anaerobic Digestion and would in fact likely increase the amount of biogas produced. Heat pre-treatment can also lower the HRT. Sterilization upfront will deal with any pathogen related effluent issues down the line and produce a biofertilizer for comestible (fit for human consumption) crops.
Treatment Methods: Treatment through Retention
Very long retention times for sewage have the ability to virtually destroy pathogens. The amount of time human excrement should be retained varies. In a very warm climate you may want to retain the waste for 60-90 days, however in cold climates (20 degrees C and below) 150 or more days of retention are recommended. Retention time can be controlled via the biodigester HRT or by holding the effluent for an additional period of time. The option that is the most economic should be considered as well as safety factors such as the access to holding tank and any other issue that involves potential exposure to humans and animals. Safety Warning: Retention methods to destroy pathogens should be confirmed by lab results before adoption.
Treatment Methods: Post Treatment and Sterilization
Biodigester effluent may also be treated in a secondary treatment phase such as Ultrafiltration, Ultraviolet Light (UV), a Treatment Wetland, Composting, or Aerobic Treatment. Ultra filtration consists of running the effluent through a membrane that only allows solubles to pass through. At the moment this technology is more likely to be used in the developed world but appropriate solutions using materials such as mangroves and other plants might be used. Ultrafiltration is practical for concentrated wastewaters that have had most solids settled out. UV treatment is a common water treatment technology however may only be practical for dilute effluents where turbidity is not an issue. A treatment wetland provides additional treatment as well as habitat for wildlife. Essentially a movement gradient is created and planted with wetland plants that facilitate nutrient and pathogen removal. This is the way wastewaters, such as storm runoff, are naturally treated in the environment. A composting process maybe allowed used to treat the effluent however it must first be dried to facilitate aeration, which is land and energy intensive. Care must be made to ensure that no one breathes in the dust from the fresh effluent during this process. The effluent may also go through an aerobic treatment process to polish the effluent however this is expensive, intensive, and removes nutrients from a productive system. Other waste treatment options may include sand filters and clarifiers.
Treatment Methods: Biodigesters Capable of Controlling Pathogens
As previously alluded to, some biodigester processes are able to control virtually all the pathogens found in sewage. These are thermophilic biodigesters, phase biodigesters, and staged biodigesters. In a thermophilic biodigester the environment within the biodigester is so hot that many pathogens are unable to survive. The environment is also far more competitive than in a regular biodigester. Pathogens are usually acclimated and most happy around body temperature. Fortunately many of the organisms capable of carrying out Anaerobic Digestion are thermophiles, or heat loving organisms. However caution must be made with the previously mentioned ammonia toxicity, as thermophilic biodigesters are far more sensitive to this issue than ambient and lower temperature biodigesters. A phase biodigester separates the respective phases that material must undergo during the anaerobic digestion process. Organic material undergoes hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Essentially a container can facilitate the conversion of organics to solubles (hydrolysis), the production of acids (acidogenesis and acetogenesis) or methane production (methanogenesis). In phase Anaerobic Digestion two or more containers are used to separate the phases. This can be done physically (removing organics as they are hydrolysed), chemically (inhibiting methane production or buffering acids to a pH where methanogenesis can occur) or biologically (acidifying the first reactor(s)). If a reactor is allowed to acidify to inhibit methane production the low pH will also create an extreme environment where some pathogens are unable to live. After an acidic environment they will be introduced to a methane-producing environment that additionally removes pathogens through microbial competition. A two-phase biodigester capable of eliminating pathogens might have an acidifying first tank, which is then fed into a thermophilic, methane producing second tank. Staged biodigesters can work in the same way by changing the competition mechanisms in various stages (reactors) though still not quite separating the phases.
Applying Effluent
Completely eliminating pathogens is not necessary when adequate care is given to applying the effluent. Biodigester effluent that still contains pathogens can be applied into subterranean leachfields (with a clarifier), used for non-edible crops and in some cases forage crops, and applied directly to land. However all these things require safety considerations. The amount of human exposure needs to be taken into consideration. Groundwater and water body contamination are all potential threats to releasing effluent not completely void of pathogens into the environment. Direct land application needs to take direct exposure into account such as use of land by children and adults. Non-edible crops are another option and also allow for nutrient capture. Crops could include energy crops, biomass production, and many others. Exposure to humans however is again a risk that must be accounted for. The simplest and safest way to dispose of effluent is to simply inject it in an already existing sewer system.
Conclusion
Biodigesters offer a variety of benefits to the person interested in ethical treatment of human waste. The most important consideration, which has not necessarily always been effectively managed, is the danger pathogens in human waste pose to health. These systems are scalable from the household, community level to the larger industrial scale applications. Successful applications can be found worldwide and as well as in history. Best of all, Anaerobic Digestion offers to turn waste into a resource.
source : Making Biogas from Human Waste
BioGas One of Alternative and Renewable Energy
Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Biogas originates from biogenic material and is a type of biofuel.
One type of biogas is produced by anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste and energy crops. This type of biogas comprises primarily methane and carbon dioxide. The other principal type of biogas is wood gas which is created by gasification of wood or other biomass. This type of biogas is comprised primarily of nitrogen, hydrogen, and carbon monoxide, with trace amounts of methane.
The gases methane, hydrogen and carbon monoxide can be combusted or oxidized with oxygen. Air contains 21 percent oxygen. This energy release allows biogas to be used as a fuel. Biogas can be used as a low-cost fuel in any country for any heating purpose, such as cooking. It can also be used in modern waste management facilities where it can be used to run any type of heat engine, to generate either mechanical or electrical power. Biogas can be compressed, much like natural gas, and used to power motor vehicles and in the UK for example is estimated to have the potential to replace around 17 percent of vehicle fuel.Biogas is a renewable fuel, so it qualifies for renewable energy subsidies in some parts of the world.
Another definition what is Biogas?
Biogas is generated when bacteria degrade biological material in the absence of oxygen, in a process known as anaerobic digestion. Since biogas is a mixture of methane (also known as marsh gas or natural gas, CH4) and carbon dioxide it is a renewable fuel produced from waste treatment. Anaerobic digestion is basically a simple process carried out in a number of steps that can use almost any organic material as a substrate - it occurs in digestive systems, marshes, rubbish dumps, septic tanks and the Arctic Tundra. Humans tend to make the process as complicated as possible by trying to improve on nature in complex machines but a simple approach is still possible, as I hope you see in some of the links below. As methane is very hard to compress I see its best use as for stationary fuel, rather than mobile fuel. It takes a lot of energy to compress the gas (this energy is usually just wasted), plus you have the hazard of high pressure. A variable volume storage (flexible bag or floating drum are the two main variants) is much easier and cheaper to arrange than high pressure cylinders, regulators and compressors.
Hot to Make BioGas and How to Use Them?
These how to make biogas from human waste. Human Waste as a Resource.
Treating human waste through Anaerobic Digestion is an incredibly ethical sanitation technology. Anaerobic Digestion occurs in biodigesters and produces a fuel (biogas), removes Biochemical Oxygen Demand (BOD) from sewage, conserves nutrients (especially nitrogen compounds) and most importantly reduces pathogens. Human waste damages the environment because it is loaded with BOD, nutrients, and anthropozoonotic diseases. This can cause a host of environmental problems that can lead to ecosystem collapse such as rendering a water body uninhabitable for many organisms. Untreated sewage causes algal blooms, red tide, and so called dead zones. Humans also suffer from untreated sewage (also called black water). Waterborne disease transmitted through human excrement is a leading cause of death worldwide, especially in the so-called developing world. Some diseases caused by untreated human sewage are Cholera, Typhoid fever, Paratyphoid fever, Salmonella, Dysentery, Gastroenteritis, Leptospirosis, Meningitis, Hepatitis, and various parasitic diseases.
The amount of biogas that can be yielded from human waste is limited in comparison with livestock manure and other feedstocks. Are stomachs are just too efficient! David House states in his excellent book that 1000 lbs of humans produces about 0.6 cubic meters of biogas (enough cooking fuel for about 1 to 2 persons). But that amount quickly adds up, please reference the internet for example projects especially in Rwanda, India and Thailand.
Untreated sewage, along with causing a prevalence of disease, developing countries are also disposing of valuable nutrients in places where fertilizers aren’t available. Biodigesters turn waste into a biofertilizer. There is also a major flaw in the sewage treatment systems of developed countries where enormous amounts of energy are used to aerate and treat sewage; Anaerobic Digestion treats sewage and also produces energy rather than consumes it. This article discusses considerations for human waste treatment and various options are outlined.
Important! Considerations
A handful of considerations need to be made for treating human waste. There are IMPORTANT disease related issues and some common physical considerations. The number 1 issue is handling human waste. Operators that handle human waste without any precautions will inevitably get sick. The waste handling process must consider the handlers. Ideally a waste treatment system will eliminate any direct handling by humans.
Typical biodigester effluent is NOT sterile. Anaerobic digestion creates a competitive environment where pathogens are out competed by non-infectious microorganisms and therefore are edged out in terms of populations. This means that pathogens are REDUCED, but not entirely eliminated. However, studies in thermophilic biodigesters (45-55 degrees C) have shown a much greater reduction of pathogens than in ambient temperature and lower temperature biodigesters (see biodigesters capable of controlling pathogens section). A waste treatment system needs to address the issue of disease during the process via pre or post treatment or the effluent needs to be disposed of accordingly.
One common consideration in designing biodigesters to fit into an already existing system is that usually human excrement is heavily diluted to facilitate movement. Toilet flushes consume large volumes of water (range from 1.3 to 2.5 gallons but about 2 gallons in the US) and designing a biodigester with for example a 30-day hydraulic retention time (HRT) for treating flushed waste requires a very large volume biodigester at a 2 gallon per flush dilution. There are biodigester designs, however, that can handle an HRT, or the amount of time a biodigester retains a waste, of only a few hours. These designs are sludge retaining reactors such as an Upflow Anaerobic Sludge Blanket (UASB) and even better performing Fixed Film Reactors. One last important factor to consider is ammonia toxicity as human waste has been reported to have a low C: N ratio. This problem can be solved via dilution and co-digestion of a carbon rich feedstock such as molasses. Animal waste is inherently safer to treat then human waste because they tend to carry less human pathogens, though consideration for some manure born pathogens ought to be made as well.
Treatment Methods: Heat Pre-treatment
During this process human excrement would be pasteurized to 70 degrees C before entering the biodigester. This would be done best before dilution to reduce energy costs and can be done using waste steam, passive solar heating, or direct combustion of biogas or any other fuel source. The process would make more of the human excrement available for Anaerobic Digestion and would in fact likely increase the amount of biogas produced. Heat pre-treatment can also lower the HRT. Sterilization upfront will deal with any pathogen related effluent issues down the line and produce a biofertilizer for comestible (fit for human consumption) crops.
Treatment Methods: Treatment through Retention
Very long retention times for sewage have the ability to virtually destroy pathogens. The amount of time human excrement should be retained varies. In a very warm climate you may want to retain the waste for 60-90 days, however in cold climates (20 degrees C and below) 150 or more days of retention are recommended. Retention time can be controlled via the biodigester HRT or by holding the effluent for an additional period of time. The option that is the most economic should be considered as well as safety factors such as the access to holding tank and any other issue that involves potential exposure to humans and animals. Safety Warning: Retention methods to destroy pathogens should be confirmed by lab results before adoption.
Treatment Methods: Post Treatment and Sterilization
Biodigester effluent may also be treated in a secondary treatment phase such as Ultrafiltration, Ultraviolet Light (UV), a Treatment Wetland, Composting, or Aerobic Treatment. Ultra filtration consists of running the effluent through a membrane that only allows solubles to pass through. At the moment this technology is more likely to be used in the developed world but appropriate solutions using materials such as mangroves and other plants might be used. Ultrafiltration is practical for concentrated wastewaters that have had most solids settled out. UV treatment is a common water treatment technology however may only be practical for dilute effluents where turbidity is not an issue. A treatment wetland provides additional treatment as well as habitat for wildlife. Essentially a movement gradient is created and planted with wetland plants that facilitate nutrient and pathogen removal. This is the way wastewaters, such as storm runoff, are naturally treated in the environment. A composting process maybe allowed used to treat the effluent however it must first be dried to facilitate aeration, which is land and energy intensive. Care must be made to ensure that no one breathes in the dust from the fresh effluent during this process. The effluent may also go through an aerobic treatment process to polish the effluent however this is expensive, intensive, and removes nutrients from a productive system. Other waste treatment options may include sand filters and clarifiers.
Treatment Methods: Biodigesters Capable of Controlling Pathogens
As previously alluded to, some biodigester processes are able to control virtually all the pathogens found in sewage. These are thermophilic biodigesters, phase biodigesters, and staged biodigesters. In a thermophilic biodigester the environment within the biodigester is so hot that many pathogens are unable to survive. The environment is also far more competitive than in a regular biodigester. Pathogens are usually acclimated and most happy around body temperature. Fortunately many of the organisms capable of carrying out Anaerobic Digestion are thermophiles, or heat loving organisms. However caution must be made with the previously mentioned ammonia toxicity, as thermophilic biodigesters are far more sensitive to this issue than ambient and lower temperature biodigesters. A phase biodigester separates the respective phases that material must undergo during the anaerobic digestion process. Organic material undergoes hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Essentially a container can facilitate the conversion of organics to solubles (hydrolysis), the production of acids (acidogenesis and acetogenesis) or methane production (methanogenesis). In phase Anaerobic Digestion two or more containers are used to separate the phases. This can be done physically (removing organics as they are hydrolysed), chemically (inhibiting methane production or buffering acids to a pH where methanogenesis can occur) or biologically (acidifying the first reactor(s)). If a reactor is allowed to acidify to inhibit methane production the low pH will also create an extreme environment where some pathogens are unable to live. After an acidic environment they will be introduced to a methane-producing environment that additionally removes pathogens through microbial competition. A two-phase biodigester capable of eliminating pathogens might have an acidifying first tank, which is then fed into a thermophilic, methane producing second tank. Staged biodigesters can work in the same way by changing the competition mechanisms in various stages (reactors) though still not quite separating the phases.
Applying Effluent
Completely eliminating pathogens is not necessary when adequate care is given to applying the effluent. Biodigester effluent that still contains pathogens can be applied into subterranean leachfields (with a clarifier), used for non-edible crops and in some cases forage crops, and applied directly to land. However all these things require safety considerations. The amount of human exposure needs to be taken into consideration. Groundwater and water body contamination are all potential threats to releasing effluent not completely void of pathogens into the environment. Direct land application needs to take direct exposure into account such as use of land by children and adults. Non-edible crops are another option and also allow for nutrient capture. Crops could include energy crops, biomass production, and many others. Exposure to humans however is again a risk that must be accounted for. The simplest and safest way to dispose of effluent is to simply inject it in an already existing sewer system.
Conclusion
Biodigesters offer a variety of benefits to the person interested in ethical treatment of human waste. The most important consideration, which has not necessarily always been effectively managed, is the danger pathogens in human waste pose to health. These systems are scalable from the household, community level to the larger industrial scale applications. Successful applications can be found worldwide and as well as in history. Best of all, Anaerobic Digestion offers to turn waste into a resource.
source : Making Biogas from Human Waste
One type of biogas is produced by anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste and energy crops. This type of biogas comprises primarily methane and carbon dioxide. The other principal type of biogas is wood gas which is created by gasification of wood or other biomass. This type of biogas is comprised primarily of nitrogen, hydrogen, and carbon monoxide, with trace amounts of methane.
The gases methane, hydrogen and carbon monoxide can be combusted or oxidized with oxygen. Air contains 21 percent oxygen. This energy release allows biogas to be used as a fuel. Biogas can be used as a low-cost fuel in any country for any heating purpose, such as cooking. It can also be used in modern waste management facilities where it can be used to run any type of heat engine, to generate either mechanical or electrical power. Biogas can be compressed, much like natural gas, and used to power motor vehicles and in the UK for example is estimated to have the potential to replace around 17 percent of vehicle fuel.Biogas is a renewable fuel, so it qualifies for renewable energy subsidies in some parts of the world.
Another definition what is Biogas?
Biogas is generated when bacteria degrade biological material in the absence of oxygen, in a process known as anaerobic digestion. Since biogas is a mixture of methane (also known as marsh gas or natural gas, CH4) and carbon dioxide it is a renewable fuel produced from waste treatment. Anaerobic digestion is basically a simple process carried out in a number of steps that can use almost any organic material as a substrate - it occurs in digestive systems, marshes, rubbish dumps, septic tanks and the Arctic Tundra. Humans tend to make the process as complicated as possible by trying to improve on nature in complex machines but a simple approach is still possible, as I hope you see in some of the links below. As methane is very hard to compress I see its best use as for stationary fuel, rather than mobile fuel. It takes a lot of energy to compress the gas (this energy is usually just wasted), plus you have the hazard of high pressure. A variable volume storage (flexible bag or floating drum are the two main variants) is much easier and cheaper to arrange than high pressure cylinders, regulators and compressors.
Hot to Make BioGas and How to Use Them?
These how to make biogas from human waste. Human Waste as a Resource.
Treating human waste through Anaerobic Digestion is an incredibly ethical sanitation technology. Anaerobic Digestion occurs in biodigesters and produces a fuel (biogas), removes Biochemical Oxygen Demand (BOD) from sewage, conserves nutrients (especially nitrogen compounds) and most importantly reduces pathogens. Human waste damages the environment because it is loaded with BOD, nutrients, and anthropozoonotic diseases. This can cause a host of environmental problems that can lead to ecosystem collapse such as rendering a water body uninhabitable for many organisms. Untreated sewage causes algal blooms, red tide, and so called dead zones. Humans also suffer from untreated sewage (also called black water). Waterborne disease transmitted through human excrement is a leading cause of death worldwide, especially in the so-called developing world. Some diseases caused by untreated human sewage are Cholera, Typhoid fever, Paratyphoid fever, Salmonella, Dysentery, Gastroenteritis, Leptospirosis, Meningitis, Hepatitis, and various parasitic diseases.
The amount of biogas that can be yielded from human waste is limited in comparison with livestock manure and other feedstocks. Are stomachs are just too efficient! David House states in his excellent book that 1000 lbs of humans produces about 0.6 cubic meters of biogas (enough cooking fuel for about 1 to 2 persons). But that amount quickly adds up, please reference the internet for example projects especially in Rwanda, India and Thailand.
Untreated sewage, along with causing a prevalence of disease, developing countries are also disposing of valuable nutrients in places where fertilizers aren’t available. Biodigesters turn waste into a biofertilizer. There is also a major flaw in the sewage treatment systems of developed countries where enormous amounts of energy are used to aerate and treat sewage; Anaerobic Digestion treats sewage and also produces energy rather than consumes it. This article discusses considerations for human waste treatment and various options are outlined.
Important! Considerations
A handful of considerations need to be made for treating human waste. There are IMPORTANT disease related issues and some common physical considerations. The number 1 issue is handling human waste. Operators that handle human waste without any precautions will inevitably get sick. The waste handling process must consider the handlers. Ideally a waste treatment system will eliminate any direct handling by humans.
Typical biodigester effluent is NOT sterile. Anaerobic digestion creates a competitive environment where pathogens are out competed by non-infectious microorganisms and therefore are edged out in terms of populations. This means that pathogens are REDUCED, but not entirely eliminated. However, studies in thermophilic biodigesters (45-55 degrees C) have shown a much greater reduction of pathogens than in ambient temperature and lower temperature biodigesters (see biodigesters capable of controlling pathogens section). A waste treatment system needs to address the issue of disease during the process via pre or post treatment or the effluent needs to be disposed of accordingly.
One common consideration in designing biodigesters to fit into an already existing system is that usually human excrement is heavily diluted to facilitate movement. Toilet flushes consume large volumes of water (range from 1.3 to 2.5 gallons but about 2 gallons in the US) and designing a biodigester with for example a 30-day hydraulic retention time (HRT) for treating flushed waste requires a very large volume biodigester at a 2 gallon per flush dilution. There are biodigester designs, however, that can handle an HRT, or the amount of time a biodigester retains a waste, of only a few hours. These designs are sludge retaining reactors such as an Upflow Anaerobic Sludge Blanket (UASB) and even better performing Fixed Film Reactors. One last important factor to consider is ammonia toxicity as human waste has been reported to have a low C: N ratio. This problem can be solved via dilution and co-digestion of a carbon rich feedstock such as molasses. Animal waste is inherently safer to treat then human waste because they tend to carry less human pathogens, though consideration for some manure born pathogens ought to be made as well.
Treatment Methods: Heat Pre-treatment
During this process human excrement would be pasteurized to 70 degrees C before entering the biodigester. This would be done best before dilution to reduce energy costs and can be done using waste steam, passive solar heating, or direct combustion of biogas or any other fuel source. The process would make more of the human excrement available for Anaerobic Digestion and would in fact likely increase the amount of biogas produced. Heat pre-treatment can also lower the HRT. Sterilization upfront will deal with any pathogen related effluent issues down the line and produce a biofertilizer for comestible (fit for human consumption) crops.
Treatment Methods: Treatment through Retention
Very long retention times for sewage have the ability to virtually destroy pathogens. The amount of time human excrement should be retained varies. In a very warm climate you may want to retain the waste for 60-90 days, however in cold climates (20 degrees C and below) 150 or more days of retention are recommended. Retention time can be controlled via the biodigester HRT or by holding the effluent for an additional period of time. The option that is the most economic should be considered as well as safety factors such as the access to holding tank and any other issue that involves potential exposure to humans and animals. Safety Warning: Retention methods to destroy pathogens should be confirmed by lab results before adoption.
Treatment Methods: Post Treatment and Sterilization
Biodigester effluent may also be treated in a secondary treatment phase such as Ultrafiltration, Ultraviolet Light (UV), a Treatment Wetland, Composting, or Aerobic Treatment. Ultra filtration consists of running the effluent through a membrane that only allows solubles to pass through. At the moment this technology is more likely to be used in the developed world but appropriate solutions using materials such as mangroves and other plants might be used. Ultrafiltration is practical for concentrated wastewaters that have had most solids settled out. UV treatment is a common water treatment technology however may only be practical for dilute effluents where turbidity is not an issue. A treatment wetland provides additional treatment as well as habitat for wildlife. Essentially a movement gradient is created and planted with wetland plants that facilitate nutrient and pathogen removal. This is the way wastewaters, such as storm runoff, are naturally treated in the environment. A composting process maybe allowed used to treat the effluent however it must first be dried to facilitate aeration, which is land and energy intensive. Care must be made to ensure that no one breathes in the dust from the fresh effluent during this process. The effluent may also go through an aerobic treatment process to polish the effluent however this is expensive, intensive, and removes nutrients from a productive system. Other waste treatment options may include sand filters and clarifiers.
Treatment Methods: Biodigesters Capable of Controlling Pathogens
As previously alluded to, some biodigester processes are able to control virtually all the pathogens found in sewage. These are thermophilic biodigesters, phase biodigesters, and staged biodigesters. In a thermophilic biodigester the environment within the biodigester is so hot that many pathogens are unable to survive. The environment is also far more competitive than in a regular biodigester. Pathogens are usually acclimated and most happy around body temperature. Fortunately many of the organisms capable of carrying out Anaerobic Digestion are thermophiles, or heat loving organisms. However caution must be made with the previously mentioned ammonia toxicity, as thermophilic biodigesters are far more sensitive to this issue than ambient and lower temperature biodigesters. A phase biodigester separates the respective phases that material must undergo during the anaerobic digestion process. Organic material undergoes hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Essentially a container can facilitate the conversion of organics to solubles (hydrolysis), the production of acids (acidogenesis and acetogenesis) or methane production (methanogenesis). In phase Anaerobic Digestion two or more containers are used to separate the phases. This can be done physically (removing organics as they are hydrolysed), chemically (inhibiting methane production or buffering acids to a pH where methanogenesis can occur) or biologically (acidifying the first reactor(s)). If a reactor is allowed to acidify to inhibit methane production the low pH will also create an extreme environment where some pathogens are unable to live. After an acidic environment they will be introduced to a methane-producing environment that additionally removes pathogens through microbial competition. A two-phase biodigester capable of eliminating pathogens might have an acidifying first tank, which is then fed into a thermophilic, methane producing second tank. Staged biodigesters can work in the same way by changing the competition mechanisms in various stages (reactors) though still not quite separating the phases.
Applying Effluent
Completely eliminating pathogens is not necessary when adequate care is given to applying the effluent. Biodigester effluent that still contains pathogens can be applied into subterranean leachfields (with a clarifier), used for non-edible crops and in some cases forage crops, and applied directly to land. However all these things require safety considerations. The amount of human exposure needs to be taken into consideration. Groundwater and water body contamination are all potential threats to releasing effluent not completely void of pathogens into the environment. Direct land application needs to take direct exposure into account such as use of land by children and adults. Non-edible crops are another option and also allow for nutrient capture. Crops could include energy crops, biomass production, and many others. Exposure to humans however is again a risk that must be accounted for. The simplest and safest way to dispose of effluent is to simply inject it in an already existing sewer system.
Conclusion
Biodigesters offer a variety of benefits to the person interested in ethical treatment of human waste. The most important consideration, which has not necessarily always been effectively managed, is the danger pathogens in human waste pose to health. These systems are scalable from the household, community level to the larger industrial scale applications. Successful applications can be found worldwide and as well as in history. Best of all, Anaerobic Digestion offers to turn waste into a resource.
source : Making Biogas from Human Waste
Sensirion Launched Flow Sensor for Flow Rates Below 100 ml/min
Precise / Measurement in the Ml range. The reliable, inexpensive SLQ-HC60 fills a gap in the existing range of products for precise measurement in the low millimeter range. Up to now, precise, reliable and inexpensive sensors for measuring flow rates in the low milliliter range in automated systems have been difficult to find. Inexpensive mechanical solutions such as small paddlewheels do not adequately meet the requirements of many applications. Sensirion AG has now filled the gap between sensors for high flow rates and its own line of microsensor products for the microliter and nanoliter ranges. The new water resistant flow meter SLQ-HC60 operates without moving parts and grants highest reliability and media compatibility. Flow rates below 100 ml/min can be measured for a wide range of media. Also the detection of bubbles in the microliter range is possible.
The new MEMS-based sensor device is specifically designed for use in automated systems. This small, highly sensitive flowmeter enables precise measurement of dynamic flow rates with a response time of less than 50 ms. The SLQ-HC60 requires a supply voltage of 24V and provides a 0-10 V analog output signal. Media separation ensures that liquids only get into contact with glass, PEEK and TEFZEL during the measuring process. Protection rating is IP65. The simple, straight flow channel of the SLQ-HC60 has an inside diameter of 1.8 mm and can be connected to 1/8’’ or 3 mm plastic hoses via threaded couplings.
The new MEMS-based sensor device is specifically designed for use in automated systems. This small, highly sensitive flowmeter enables precise measurement of dynamic flow rates with a response time of less than 50 ms. The SLQ-HC60 requires a supply voltage of 24V and provides a 0-10 V analog output signal. Media separation ensures that liquids only get into contact with glass, PEEK and TEFZEL during the measuring process. Protection rating is IP65. The simple, straight flow channel of the SLQ-HC60 has an inside diameter of 1.8 mm and can be connected to 1/8’’ or 3 mm plastic hoses via threaded couplings.
Electrochemical, Solid State Electrochemical and Thermocatalytic Gas sensors
Oxygen sensors usually work according to the amperometric method, in which an electrolysis flow is measured which is proportional to the oxygen concentration or the partial pressure. These sensors frequently have the disadvantage that the electrolyte material used is changed by the electrochemical reaction taking place. The sensor therefore has a limited working life, which is usually about one year.
The new electrochemical oxygen sensors from MST Intertrade (Germany) do not suffer from this disadvantage. They use a new type of electrolyte material, whose electrochemical reaction does not result in the passivation of the electrode. The working life quoted by the manufacturer is therefore at least 10 years (20.8% O2 at 20 ‘C). The sensitivity is reduced within three years by less than 15%, and after 10 years by a maximum of 30%. The sensors are available in two versions, with measuring ranges from 0% to 30% O2 or 0% to 100% O2. They can be sued in a very wide working temperature range -35’C to +50’C. The sensors show no cross-sensitivity with most gases. At a temperature of 20’C for example, 10% CO, 30% CO2 and 30% H2 do not interfere with the measurement. The company also offers micro-sensors, which are used particularly in the area of work safety for portable gas measuring devices.
These sensors are used for example in the mining industry, in order to warn miners of too low oxygen concentrations or dangerous methane concentrations. With a working life of at least three years, these sensors are also extremely durable.
The new electrochemical oxygen sensors from MST Intertrade (Germany) do not suffer from this disadvantage. They use a new type of electrolyte material, whose electrochemical reaction does not result in the passivation of the electrode. The working life quoted by the manufacturer is therefore at least 10 years (20.8% O2 at 20 ‘C). The sensitivity is reduced within three years by less than 15%, and after 10 years by a maximum of 30%. The sensors are available in two versions, with measuring ranges from 0% to 30% O2 or 0% to 100% O2. They can be sued in a very wide working temperature range -35’C to +50’C. The sensors show no cross-sensitivity with most gases. At a temperature of 20’C for example, 10% CO, 30% CO2 and 30% H2 do not interfere with the measurement. The company also offers micro-sensors, which are used particularly in the area of work safety for portable gas measuring devices.
These sensors are used for example in the mining industry, in order to warn miners of too low oxygen concentrations or dangerous methane concentrations. With a working life of at least three years, these sensors are also extremely durable.
IR Gas Sensors in Aluminum Cuvette with Improved Performance
In many applications in process- and analysis engineering, the exact detection of gas concentrations is dispensable. Contrary to other measurement processes, the sensors that are based on the infrared absorption offer important advantages. These sensors deploy the character of the gases, to absorb the infrared radiation at a specific wavelength. Since this is characteristic for the respective kind of gas, the sensor works very selectively and barely shows interference opposite to other gases. In compassion to electrochemical and catalytic sensors, these sensors do not show any seasoning effects.
With the new version of the smartMODULFLOW, the smartGAS (Germany) now offers an OEM-sensor that is based on the IR Radiant source, an interference filter for the wavelength selection and an IR dual detector is housed in an aluminum cuvette for this reason. This cuvette can be integrated into the process and can be flowed through with the respective gas. This buildup provides importing advantages, especially in procedural applications. The aluminum cuvette for example can be held at a constant temperature to exclude temperature dependent effects, As a result from this, a higher measurement accuracy can be achieved. By an additive isolation of the optical components of the gas flow, diverse flow effects can be minimized. Furthermore, the modular and easy to install construction allows a higher flexibility, because the measurement setup of smartGAS is easy to adjust to the customer specific measurement problem, for example by the adaptation of the light path.
The evaluation electronics with the interfaces of the sensor module resides on the board beyond the cuvette. Beneath the standard interfaces (4…20 mA, 0…2,5V) there also is a serial RS485 interface available. The also integrated watchdog, that observes the function of the sensors technology, is of high importance, especially at security relevant applications. The new aluminum version of the smartMODULFLOW is available for the following gases : Acetylene, Butane, Ethane, Ethylene, Carbon dioxide, Carbon monoxide, propane, Methane, R134a and sulfur hexafluoride.
With the new version of the smartMODULFLOW, the smartGAS (Germany) now offers an OEM-sensor that is based on the IR Radiant source, an interference filter for the wavelength selection and an IR dual detector is housed in an aluminum cuvette for this reason. This cuvette can be integrated into the process and can be flowed through with the respective gas. This buildup provides importing advantages, especially in procedural applications. The aluminum cuvette for example can be held at a constant temperature to exclude temperature dependent effects, As a result from this, a higher measurement accuracy can be achieved. By an additive isolation of the optical components of the gas flow, diverse flow effects can be minimized. Furthermore, the modular and easy to install construction allows a higher flexibility, because the measurement setup of smartGAS is easy to adjust to the customer specific measurement problem, for example by the adaptation of the light path.
The evaluation electronics with the interfaces of the sensor module resides on the board beyond the cuvette. Beneath the standard interfaces (4…20 mA, 0…2,5V) there also is a serial RS485 interface available. The also integrated watchdog, that observes the function of the sensors technology, is of high importance, especially at security relevant applications. The new aluminum version of the smartMODULFLOW is available for the following gases : Acetylene, Butane, Ethane, Ethylene, Carbon dioxide, Carbon monoxide, propane, Methane, R134a and sulfur hexafluoride.
Compact Sensors for Explosive Dust Atmospheres
Inductive proximity switches from the EGE (Germany) IGEX20 Series can be installed in Ex zone 20. Certified according to ATEX marking II 1D IP67 T80 ‘C, they are operated with 24 V DC (direct supply). They do not require an amplifier. The switches come in size. Featuring IP67 protection, the sensors are fit for rugged industrial environments. They can be connected via a fixed cable or an M12 plug connector.
The SHT21Generation of Digital Humidity Sensors
Sensirion ( Switzerland ) is launching its new generation of humidity and temperature sensors at Sensor+Test 2009. The SHT21 conforms to the current trend of saving space and reducing energy consumption. The new humidity sensor incorporates the existing strengths of the successful SHT11 while significantly enhancing and improving them. For instance, The SHT21 sensor not only features long-term stability, full calibration and a digital interface, but also supports additional communication modes, including analog modes. In addition, sensor reliability and performance have been boosted by using advanced semiconductor technology
The QFN components are resin encapsulated to minimize the sensor dimensions. With a 3 x 3-mm footprint and a height of 1.1mm, the sensor fulfills practical every wish with regard to the compactness of integrated sensors. Encapsulation of the semiconductor chip also provides reliable protection against ambient conditions and thus increases the stability of the sensor. Like the sensors in the SHT1x series, the SHT21 can be processed in a reflow oven. It is correspondingly suitable for use in mass production. To meet the demands of complex applications, the manufacturing concept has been significantly improved with regard to test routines. Numerous innovations have also been introduced to futher improve quality insurance.
The QFN components are resin encapsulated to minimize the sensor dimensions. With a 3 x 3-mm footprint and a height of 1.1mm, the sensor fulfills practical every wish with regard to the compactness of integrated sensors. Encapsulation of the semiconductor chip also provides reliable protection against ambient conditions and thus increases the stability of the sensor. Like the sensors in the SHT1x series, the SHT21 can be processed in a reflow oven. It is correspondingly suitable for use in mass production. To meet the demands of complex applications, the manufacturing concept has been significantly improved with regard to test routines. Numerous innovations have also been introduced to futher improve quality insurance.
CMOS Digital Photo IC for Colour Sensing
Hamamatsu Photonics (UK) introduce a 12-bit digital output colour sensor photo IC. The S9706 device consist of a matrix photodiode array, coupled to a RGB (Red, Green, and Blue) filter matrix to give colour response. The device is combined with “in house” CMOS processing electronics and is all contained within a monolithic silicon chip.
The output of the S9706 is in 12-bit digital format with the colour intensity of red,green and blue read out sequentially at potentially high speed. The S9706 is easily operated with a standard 3.3V CMOS power supply and has higher speed and is much lower in cost than three colour image sensors. It is also highly accurate and is easier to implement than current discrete three colour photodiodes.
The S9706 is ideal for applications such as colour sensors for displays (LCD, televisions & monitors), colour rendering for LED backlights, office and industrial lighting control, in-line industrial product inspection, colour printing applications, bank note verification, environmental sensors and a wide variety of other optical sensors requiring colour measurements.
The output of the S9706 is in 12-bit digital format with the colour intensity of red,green and blue read out sequentially at potentially high speed. The S9706 is easily operated with a standard 3.3V CMOS power supply and has higher speed and is much lower in cost than three colour image sensors. It is also highly accurate and is easier to implement than current discrete three colour photodiodes.
The S9706 is ideal for applications such as colour sensors for displays (LCD, televisions & monitors), colour rendering for LED backlights, office and industrial lighting control, in-line industrial product inspection, colour printing applications, bank note verification, environmental sensors and a wide variety of other optical sensors requiring colour measurements.
Stainless Steel Level Pressure Sensors Available On Fast Delivery High Performance Sensors at Low Cost
GE Sensing & Inspection Technologies (UK) is introducing its new 1030 Series Druck stainless level pressure sensor in response to a market demand for a low cost, high performance sensor which offers fast delivery times. Its development has been made possible by applying volume batch manufacturing techniques and by fitting cables to units individually. As a result the 1030 brings the performance and quality of what was previously a bespoke product to a much wider audience.
The new 1030 features a fully welded, 316 stainless steel construction and offers a 4-20mA output for zero to full scale pressure. Operating FS pressure range extends from 3.5 to 100 mH2O gauge. It has an accuracy of 0.25% full scale and can be submerged in all fluids compatible with its stainless steel body, its polyurethane cable and its Delrin nose cone. The vented polyurethane electrical connection cable has integral Kevlar strain relief cord rated to 54kg load and water ingress protection is to IP68 at 700 mH2O. Cable is available in lengths from 1 to 600m and is factory fitted to individual orders.
As lan Abbott, product manager, level, at GE Sensing & Inspection Technologies confirms. “ Because the new hydrostatic liquid level sensor is now batch produced, there is no longer any requirement for a minimum order quantity and instruments can be delivered on site with very short lead times.”
The new 1030 features a fully welded, 316 stainless steel construction and offers a 4-20mA output for zero to full scale pressure. Operating FS pressure range extends from 3.5 to 100 mH2O gauge. It has an accuracy of 0.25% full scale and can be submerged in all fluids compatible with its stainless steel body, its polyurethane cable and its Delrin nose cone. The vented polyurethane electrical connection cable has integral Kevlar strain relief cord rated to 54kg load and water ingress protection is to IP68 at 700 mH2O. Cable is available in lengths from 1 to 600m and is factory fitted to individual orders.
As lan Abbott, product manager, level, at GE Sensing & Inspection Technologies confirms. “ Because the new hydrostatic liquid level sensor is now batch produced, there is no longer any requirement for a minimum order quantity and instruments can be delivered on site with very short lead times.”
The HCN/C-100 Sensor Tool for Hydrogen Cyanide
Membrapor (Switzerland) has successfully developed a sensor for Hydrogen Cyanide (HCN). The HCN/C-100 exhibits an exceptionally short response time of t90 < 20 s. With a sensitivity of 600 nA/ppm and a very stable baseline it is perfectly suitable for measurements in the lower ppm-range. This sensor is meant for the use in HCN monitors to protect workers for accidental releases of hydrogen cyanide gas. The HCN/C-100 is suited for use in the extraction of precious metals such as gold and silver, in electroplating, metallurgy and in the production of a wide range of organic chemicals, e.g., acrylonitrile, methyl methacrylate, and adiponitrile that are used in producing synthetic fibers and plastics.
The cross-sensitivity of the HCN/C-100 to carbon monoxide and to hydrogen is only 2% and the sensor life expectancy is 2 years. Since our last participation at the Sensor+Test exhibition, the product range of Membrapor was expanded by another 32 sensors. Membrapor also provides customer-specific solutions. Therefore, please take this opportunity to meet us and to discuss your applications at our booth 12-274 at Sensor+Test in Nuremberg.
The cross-sensitivity of the HCN/C-100 to carbon monoxide and to hydrogen is only 2% and the sensor life expectancy is 2 years. Since our last participation at the Sensor+Test exhibition, the product range of Membrapor was expanded by another 32 sensors. Membrapor also provides customer-specific solutions. Therefore, please take this opportunity to meet us and to discuss your applications at our booth 12-274 at Sensor+Test in Nuremberg.
The Corona CAD HPLC Water Detector Control Software
Waters Corporation ( USA ) and ESA Biosciences announced today the availability of the Corona CAD HPLC detector control in Waters Empower 2 Chromatography Data Software (CDS).
The new software option responds to the needs of laboratories that have standardized on Water Alliance HPLC System and the ESA Corona CAD charged-aerosol HPLC detector for analytical and preparative-scale HPLC analyses. Scientists now have single-point system management and control over the entire system including the Corona CAD detector in Empower 2 software. By raising the level of compatibility, Waters is striving to give customers the ability to achieve higher productivity and efficiency.
ESA will provide free-of-charge the Empower 2 Software driver to its existing Corona CAD customers. New customers will receive the driver set within the instrument’s start up kit.
The new software option responds to the needs of laboratories that have standardized on Water Alliance HPLC System and the ESA Corona CAD charged-aerosol HPLC detector for analytical and preparative-scale HPLC analyses. Scientists now have single-point system management and control over the entire system including the Corona CAD detector in Empower 2 software. By raising the level of compatibility, Waters is striving to give customers the ability to achieve higher productivity and efficiency.
ESA will provide free-of-charge the Empower 2 Software driver to its existing Corona CAD customers. New customers will receive the driver set within the instrument’s start up kit.
Sensitive LCMS-2020 System Mass Spectrometer
Shmadzu (Germany) has introduced a new compact LCMS-2020 single quadrupole mass spectrometer, which features the world’s fastest scanning capabilities. Utilising patent pending ultrafast (UF) technology, the LCMS-2020 has faster measurement speed and significantly higher sensitivity than any other single quadrupole analyzer. This provides more accurate detection of trace impurities in environmental pollutants and other contaminants.
The new UFscanning technology achieves mass spectrum measurement speeds of 15,000 u/sec without sacrificing sensitivity or resolution, thus obtaining the best chromatography for the fastest LC conditions. The novel UFswitching technology achieves industry-leading 15 ms polarity switching, enabling accurate data from even the fastest chromatographic peaks without any loss of peak height.
The new UFscanning technology achieves mass spectrum measurement speeds of 15,000 u/sec without sacrificing sensitivity or resolution, thus obtaining the best chromatography for the fastest LC conditions. The novel UFswitching technology achieves industry-leading 15 ms polarity switching, enabling accurate data from even the fastest chromatographic peaks without any loss of peak height.
Niton XL3T Series XRF Analyzer with Large Area Drift Detector
Thermo Fisher Scientific (USA) introduce Thermo Scientific Niton XL3t Series with geometrically optimized large area drift detector (GOLDD) technology. The Niton analyzer’s groundbreaking GOLDD technology delivers improvements in light element detection, overall sensitivity and measurement times – as much as 10 times faster than conventional Si-PIN detectors, and up to three times more precise than conventional smaller, silicon drift detectors.
Thermo Fisher Scientific was able to surpass the performance of conventional Si-PIN and SDD detectors by combining the award-winning Niton XL3t 50kV,2-watt X-ray tube, closely optimized geometry and patented signal processing hardware and software. When combined with the company’s proprietary large area drift detector, it creates GOLDD technology, delivering superior performance in the form of faster analysis and lower detection limits. Furthermore, this innovation allows light element detection of magnesium, aluminum, silicon, phosphorus and sulfur without helium or vacuum purging, a significant productivity and user benefit.
“ The Niton XL3t with GOLDD technology brings true lab-quality performance to a handheld XRF analyzer,”said Bob Wopperer, director of business development for portable analyzer products within Thermo Fisher Scientific. “ The product is easy to use, delivers fast analysis, is extremely accurate, and can measure light elements without helium or vacuum assistance. These features make it the ideal, multi-purpose tool for analyzing metal alloys, carrying out mining exploration and mapping, detecting soil contaminants, or screening toys, electronics and other consumer goods for prohibited substances.”
For example, the Niton XL3t GOLDD is the definitive tool for scrap metal recycling, making it easier to sort aluminum, titanium and bronze alloys, as well as achieving superior performance for tramp and trace element analysis. And in mining exploration, the instrument’s low detection limits are designed to allow geologist to identify anomalies at or below the averages naturally found in the earth’s crust, something previously not possible with handheld XRF.
Thermo Fisher Scientific was able to surpass the performance of conventional Si-PIN and SDD detectors by combining the award-winning Niton XL3t 50kV,2-watt X-ray tube, closely optimized geometry and patented signal processing hardware and software. When combined with the company’s proprietary large area drift detector, it creates GOLDD technology, delivering superior performance in the form of faster analysis and lower detection limits. Furthermore, this innovation allows light element detection of magnesium, aluminum, silicon, phosphorus and sulfur without helium or vacuum purging, a significant productivity and user benefit.
“ The Niton XL3t with GOLDD technology brings true lab-quality performance to a handheld XRF analyzer,”said Bob Wopperer, director of business development for portable analyzer products within Thermo Fisher Scientific. “ The product is easy to use, delivers fast analysis, is extremely accurate, and can measure light elements without helium or vacuum assistance. These features make it the ideal, multi-purpose tool for analyzing metal alloys, carrying out mining exploration and mapping, detecting soil contaminants, or screening toys, electronics and other consumer goods for prohibited substances.”
For example, the Niton XL3t GOLDD is the definitive tool for scrap metal recycling, making it easier to sort aluminum, titanium and bronze alloys, as well as achieving superior performance for tramp and trace element analysis. And in mining exploration, the instrument’s low detection limits are designed to allow geologist to identify anomalies at or below the averages naturally found in the earth’s crust, something previously not possible with handheld XRF.
The 7693A Automated Liquid Sampler (ALS)
The 7693A ALS is a completely new design, offering substantial gains in throughput, flexibility, sample preparation automation and serviceability for all current Agilent (Asia) benchtop GC models. The new ALS is modular, letting user configure the exact autosampler they need – starting from basic injector with a 16-sample turret, and later adding capabilities as needs expand. Options include a second injection tower, a 150-vial sample tray and a vial heater/mixer/barcode reader for long unattended operation.
Agilent’s exclusive fast-injection technology is twice the speed of any competitive ALS. Injection time of less than 100 milliseconds minimizes samples degradation and the effects of needle discrimination. The two-injector configuration doubles sample throughput. Agilent offers an optional Heater/Mixer/Barcode reader module that can automate a number of pre-injection procedures. This offers substantial savings in time and labour, and operator-to-operator variability is eliminated. Solvent consumption and waste expense can be trimmed by as much as 90 percent.
Agilent’s exclusive fast-injection technology is twice the speed of any competitive ALS. Injection time of less than 100 milliseconds minimizes samples degradation and the effects of needle discrimination. The two-injector configuration doubles sample throughput. Agilent offers an optional Heater/Mixer/Barcode reader module that can automate a number of pre-injection procedures. This offers substantial savings in time and labour, and operator-to-operator variability is eliminated. Solvent consumption and waste expense can be trimmed by as much as 90 percent.
