In
France, it is well known, we have more oil but we still have
ideas
Preamble
The
discomfort of unpleasant odors has become a social problem.
Some bad smells are, moreover, detrimental to our health
like other products with little or no smell.
The odors harmful or not, that we breathe daily are
decisive for our well-being and our health.
Over
time, the individual manages to get used to the bad
smells and these being invisible, no provision is generally
taken to protect themselves from it.
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Who is the inventor ?
The
inventor, chemical engineer of Research & Development in pharmaceutical
industry, now retired and independent researcher, is the nephew
of André Bondouy,
the founding President of the company
SEPPIC.
The
process was
born from the imagination of a Normand chemist born
in the mythical village who saw circulating the first
car equipped with an engine designed by Édouard
Delamare-Deboutteville
(1856 à 1901) who
had the idea in 1883 to equip a hunting wagon with a
gas engine.
But the experiment ended abruptly with the explosion
of the gas container.
The following year he designed and ran the first petrol
car powered by an internal combustion engine.
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How was PTC System born ?
PTC
System is a totally new and innovative design technology that
was patented for France in July 2018 with an international
extension for 152 countries registered in August 2018.
The
idea of the process is the result of the observation of the
reaction of an organic molecule with a sulfur derivative very
malodorous, in this case the condensation between chloroethanol
and dodecylmercaptan, giving rise to a new organic molecule
perfectly odorless very easily biodegradable.
This
observation was the trigger to look for a simple and inexpensive
reagent and if possible easily accessible.
The DAVID process is born.
Research has been undertaken for the choice of an organic
molecule already marketed, affordable, easy and safe to use.
Innovation is therefore based on the implementation of an
original formulation, without any oxidant, which acts on the
pollutant by transforming it into an odorless and bio-available
organic compound.
This formulation is based on a molecule well known and used
in chemistry since the 19th century for the synthesis of various
specialties. The use of this molecule in the fields we are
interested in is the key to the process, which represents
a very important advance on the technical and economic levels.
PTC
System is a technology for purifying gaseous, liquid or vesicular
aerosol compositions containing pollutants that are harmful
to health and the environment, or simply smelly.
-
Pollutants are Volatile Inorganic Compounds (VICs)
- CO2,
COS, NOx, halohydric acids, H2S, SO2, SOCl2, SO2Cl2,
etc...
- Pollutants
are Volatile Organic Compounds (VOCs)
-
amine, amide, nitrile, aldehyde, ketone, ester, carboxylic
acid, alcohol, thiol, disulfide, thioester, halogenated
organic compounds, phosgene and hydrogen cyanide,
etc...
The
originality of the process resides on the one hand in the
choice of the reagent which combines with the pollutants to
be treated and on the other hand in the final natural biological
destruction in the purification station not generating any
new gaseous pollution.
This
purification system is unique in its design and applications.
It makes it stand out from the competition and to improve
the productivity of the capture / treatment facilities, as
long as its
economic record
is advantageous.
The new patent is based on the existing patent of the DAVID
process (Process for the purification of gaseous or liquid
effluents containing sulfur derivatives) for which it constitutes
an improvement.
view history
Industry
sector
Process for the purification of gaseous or liquid
effluents containing sulfur derivatives
The
present invention relates to a process for the purification
of gaseous or liquid effluents containing sulfur
derivatives (H2S, alkyl mercaptan, SO2).
The
process has been the subject of a French, European
and US patent.
An improvement is currently the subject of a new
patent.
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Hydrogen
sulphide (H2S) and mercaptans (R-SH)
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H2S
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Méthanethiol
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Hydrogen
sulphide is an extremely poisonous gas, smelly even when
it is present in very small quantities, and corrosive.
Its presence as well as that of alkyl mercaptans which
have the same disadvantages as H2S from the olfactory
point of view in the effluents (gaseous or liquid), industrial
in particular, represent a considerable danger for the
health of the living organisms or the plant environment.
It
is therefore of utmost importance in the fight against
pollution, to eliminate hydrogen sulphide as well as the
alkyl mercaptans present in industrial effluents (industries
related to energy, chemistry, wood, paper and viscose,
food industry), waste (industry of animal by-products,
manure, household waste) or in treatment plants.
Sulfur
Dioxide (SO2)
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SO2
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The
presence of SO2 in effluents, particularly industrial
ones, also represents a considerable danger for the plant
environment. Indeed, its emission is responsible for an
increase of acidity in the atmosphere and generates the
phenomenon of acid rain.
The
SO2-producing industries include refineries, hydrocarbon
waste processing industries, chemical industries (mineral
chemistry: sulfuric acid and titanium oxide production,
organic chemistry), paper industries, agro-industries
food and materials industries. Various solutions have
been proposed for eliminating these various sulfur compounds
from the effluents (gaseous or liquid).
See
the articles::
Competitive Techniques and
Industrial Deodorization by
Bleach.
Technical
description of the DAVID process
The
DAVID process is carried out in a physico-chemical
deodorization process consisting of a transfer of
odorous gas molecules to a liquid phase.
This process is characterized by a chemical washing
of the stale air against the current, with the aid
of alkaline aqueous solutions, inside series placed
lathes.
These towers are lined with inert material that
promotes gas-liquid contact.
Depending on the nature of the compound to be removed,
a basic neutralizing agent is added to the wash
water in order to accelerate the gas-liquid transfer,
thereby increasing the efficiency of the treatment.
The additional addition of the specific reagent,
claimed in the DAVID process, in turn contributes
not only to intensifying this transfer process,
but also to regenerating the washings by chemically
modifying the absorbed molecules which have the
property of being odorless. and biodegradable.
The
DAVID process makes it possible to treat highly
concentrated gaseous effluents from odorous compounds.
Highly reliable, this technique achieves purifications
greater than 99% guarantee the total absence of
olfactory nuisances.
The characteristics of an inert material that promotes
packing (nature, specific surface, volume, height)
are calculated to optimize the gas-liquid contact
time and the transfer of molecules.
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How does this original process work ?
The DAVID process is carried out in a physico-chemical
process consisting of a transfer of gaseous molecules
to a liquid phase.
The
object of the present invention is to provide a process
for the purification of gaseous or liquid effluents containing
one or more sulfur derivatives, such as H2S, mercaptans
or SO2, which eliminates the disadvantages of the solutions
aimed at the same purpose proposed in the prior art, especially
in that the method according to the present invention
allows a quantitative purification efficiency of the order
of 100%, does not require any particular installation
(use of any gas washing column, for example), and provides
a stable, biodegradable and nontoxic substitution product.
The subject of the present invention is a process for
purifying effluents (gaseous or liquid) containing sulphurous
derivatives (H2S, alkyl mercaptan, SO2), characterized
in that it comprises:
(A) alkalinization of the effluent to be treated
at a pH>9 in the presence of a base of general formula
M-OH in which M represents an alkali metal, an alkaline
earth metal, a condensing agent between the part organic
form of a specific reagent and the sulfur derivative or
a phase transfer agent and in particular a quaternary
ammonium or a ligand.
(B) contacting the product obtained in (A) with
a specific organic reagent.
According
to an advantageous embodiment of said method, steps (A)
and (B) are carried out simultaneously. This capture and
depollution process also applies to the simultaneous treatment
of several sulfur derivatives for very large concentrations.
(C) The final destruction of the capture products
after the simultaneous process of absorption and chemical
modification (A + B) The operation is carried out in a
biological purification station.
The organic compounds present and formed during the condensation
reaction are digested by the aerobic bio-purification
process of the treatment plant.
The
principle of biological treatment is based on the degradation
of organic compounds by microorganisms. Organic matter
present in the main liquid substrate in the presence of
oxygen, nitrogen and phosphorus sources, trace elements
and water is degraded to CO2, H2O, S and metabolites (reaction
by-products ).
The
originality of the process resides on the one hand in
the choice of the reagent which combines with the pollutants
to be treated and on the other hand in the final natural
biological destruction in the purification station not
generating any new gaseous pollution. This purification
system is unique in its design and applications. It makes
it stand out from the competition and to improve the productivity
of the capture / treatment facilities, as long as its
economic
record is advantageous.
The new patent is based on the existing patent of the
DAVID process (Process for the purification of gaseous
or liquid effluents containing sulfur derivatives) for
which it constitutes an improvement.
Equipment needed for the DAVID
process
This
process is feasible on a single wash tower if the ammonia/amine
concentrations are less than 0.4 ppm.
GasWash module details
The process is characterized by a physicochemical
washing of the gaseous flow against the current,
using aqueous alkaline solutions, inside the
scrubber.
The basic neutralizing agent (soda or potash)
is added to the water to accelerate the gas-liquid
transfer, and thus increase the effectiveness
of the treatment.
The
additional addition of a specific reagent in
turn not only helps to intensify this transfer
process, but also to regenerate the washings
by chemically modifying the absorbed molecules
which have the property of being odorless and
biodegradable.
In the tower, air is introduced from the bottom
up and the washing solutions sprayed countercurrent,
from top to bottom.
These towers are lined with inert material that
promotes gas-liquid contact.
The tower is equipped with a recycling pump.
The foot of the tower serves as a retention
volume and as a suction cover for the recirculating
bath pump.
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Operating mode:
An
Excel
spreadsheet allows you to determine the amounts
of reagent and soda depending on the gas flow and to compare
the cost of treatment with bleach and other oxidants.
For that it is important to know and to inform precisely
in the blue boxes:
-
The hourly flow rate in m3
-
The daily treatment time
-
The concentration of the compounds to be collected in mg/m3
In
the suction tank is charged in the order the calculated
amounts of alkaline solution of soda or potash, then the
40% solution of the reagent. The additional water determined
in the spreadsheet corresponding to 20 volumes of the
pure reagent is charged. The reaction medium displays
a pH value>11.
The circulation pump is activated then the gas flow valve
is gradually released and controlled at the desired flow
rate. The end of the reaction is determined and controlled
by pH<9.
The process adapts to any type of installation already
existing
-
In the case of an installation with only one tower,
it is a unit operation (batch):
The
tower is emptied, the liquid effluent is discharged
to the industrial water receiving basin.
The tower can be reloaded for another operation.
Such
an installation can also operate continuously
with dosing pumps and simultaneous evacuation
of the washing juices.
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- In the case of an installation equipped with
several towers, it allows a continuous operation:
This
type of installation with 2 or 3 floors, or more,
will be suitable for continuous treatment.
Once
the arrival one turn era saturation controlled
by pH-metry (pH <9), the flow is switched to the
2 nd round. Meanwhile, the 1 st tower is reloaded
and so on ...
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The method according to the invention therefore does not
require specific specific equipment.
Biological
treatment of liquid effluents in wastewater treatment
plants:
The
process according to the invention makes it possible to
obtain an absolutely odorless and colorless liquid treated
product which can be directly discharged to a self-neutralization
pond or a water treatment basin of a treatment plant,
moreover, acidification does not regenerate mercaptan,
SO2 or hydrogen sulphide.
Biological treatment in wastewater treatment plants does
not create any new nuisance either at the station itself
or at the level of the sewerage network.
The BOD (Biological Oxygen Demand) and COD (Chemical Oxygen
Demand) measurements are consistent with rejection standards
and improved compared to conventional oxidative destruction
processes.
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Sustainable
Development Sector
Process
for the purification of gaseous, liquid or vesicular aerosol compositions
containing pollutants which are harmful to health and the environment
or which are simply odor-causing.
This
first experience in the field of odors has led this Engineer to
reflect and guide his research in other areas of industry and the
environment.
The
research quickly led to innovative improvements and a complete overhaul
of the DAVID process towards Sustainable Development with the invention
of the PTC system (Pollution Trap Concept).
This brand new system is currently the subject of an international
patent application.
Today,
the PTC system is mainly in the field of waste methanation (biogas
purification), a particularly advanced field.
According
to Ademe, the sector could provide more than 14% of French gas consumption
in 2030.
In its document "Contribution to the development of energy visions
2030-2050", the agency estimates that with 600 biogas plants per
year (ie almost half as much as in Germany), the accessible deposit
would be 6 Mtep primary in 2030 (ie 20% of the estimated gas consumption
for this period).
Whatever
the nature of the biogas, the PTC system separates the biogas from
its impurities (CO2, H2S, VOC, Siloxanes). The methane content of
biogas then goes from 45% to 98% and can be directly injected into
the national gas distribution network. The advantage of our PTC
process is that it uses reliable, robust, widely proven technology
that comes directly from industry. This system adapts according
to the variation of the methane richness according to the composition
of the incoming raw biogas.
The
main sources of biogas
Beyond
the new public support mechanisms expected by market players, it
is above all "the structuring of the sector that is required as
a necessity. Inputs, the most common sources of biogas (containing
biomethane), come from voluntary or involuntary organic material
stores that originate from:
Livestock effluents (manure)
-
Slurry (composed of liquid and solid excrement of animals)
- Manure
(mixing manure with animal litter: straw, hay ...).
They represent the major part of the effluents.
Livestock
effluents are derived from livestock activities, particularly cattle
and pigs, and are located in livestock buildings.
Energy crops
These are crops grown primarily for energy production purposes.
They can be used as inputs in biogas plants that will use the energy
power of these plants.
Energy Intermediate Crops (CIVE) & Intermediate Nitrate
Trap Crops (CIPAN)
-
An intermediate energy culture (CIVE) is a culture implanted and
harvested between two main crops in a crop rotation.
CIVE can be harvested for use as an input into an agricultural
biogas plant.
-
A nitrate trap intermediate culture (CIPAN) is a temporary crop
of fast-growing plants intended to protect plots between two main
crops. These cutlery are mandatory in some areas or areas because
of nitrate pollution.
By using them for their growth, the canopy plants trap the remaining
nitrates at the end of the previous main crop.
Crop waste
Agricultural waste from crops (eg corn cane).
Sludge and by-products of the agro-food industries
The agri-food industries generate all sorts of co-products during
the technological processes they use to develop their finished products
(dairy products, meat, grain products, fruits and vegetables, etc...).
Once the product is valued, it will be called "co-product".
Sludges of agro-industrial origin come from slaughterhouses, dairies,
cheese factories, biscuits, breweries, canneries, etc...
Animal by-products (SPA)
European Regulation (EC) No 1069/2009 classifies animal by-products
into three categories.
It defines the manner in which the materials of each category must
or may be eliminated or upgraded for certain uses in order to maintain
a high level of hygiene.
Household waste
This is waste from households and assimilated waste.
Waste produced by municipal services, waste from collective sanitation,
street cleaning waste, market do not fall within this scope.
Green waste (DV)
Green waste refers to vegetable waste resulting from the maintenance
and renewal of public and private green spaces (parks and gardens,
sports fields, etc.), local authorities, public and parapublic bodies,
private companies and individuals.
Other waste (STEP sludge, etc.)
Sludge treated in urban wastewater treatment plants is the result
of human activity.
Their valuation for biomethane production has been authorized since
2014.
Why methanize our waste ?
Anaerobic
digestion, still underutilized, appears to be a response to
the dual issue of waste management and the development of
renewable energies; not to mention the fight against greenhouse
gases including CO2.
The
principle of anaerobic digestion consists of recovering organic
waste in order to recover it in the form of biogas by anaerobic
fermentation. Organic waste can come from agricultural activities
(manure, manure), industrial and tertiary (including waste
from LPNs) or communities (catering waste, grass clippings
...).
Biogas is composed in particular of methane in variable proportion,
which gives it an energy potential.
This biogas, after purification, is used to produce electricity
and / or heat. It can also be injected into the gas distribution
network, or even be used in fuel gas.
To
date, the
purification of biogas requires a succession of operating
phases.
The P.T.C. has the advantage of treating all the undesirable
compounds in a single operation.
In
addition to biogas, agricultural biogas allows the production
of a fertilizer material, the digestate, which can be spread
(as part of a spreading plan, or as a standard product after
composting). The development of anaerobic digestion is fully
in line with the objectives of the energy transition law for
green growth promulgated on August 18, 2015.
France
wants to develop by 2020 renewable energy up to 23% of the
energy mix, with a strong contribution of biomass to these
objectives (wood energy and biogas). Thus, the State sets
a goal of 1,500 methanizers in 3 years, and methanization
is at the heart of the plan Energy Methanization Nitrogen
Autonomy (EMAA) of March 29, 2013
(see
website http://agriculture.gouv/Plan-Energie-Methanisation).
It
should be noted that in this configuration, the biogas is
not purified therefore a source of olfactory nuisance due
to H2S and NH3.
On the other hand, fermentation CO2 is released into the atmosphere
(greenhouse gas).
The
current biogas-biomethane sector
The
uses of biomethane are the same as for natural gas: hot water,
heating, cooking, industrial needs, etc...
One of the relevant valuations still unknown is the valuation
in fuel.
The use of biomethane in transportation fuel (referred to
as bioGNV) would reduce greenhouse gas emissions in this sector.
In addition, it being understood that bioGNV and NGV (natural
gas for vehicles) have the same chemical composition, gas-powered
vehicles and filling stations can be powered by bioGNV without
technical modifications.
Diagram of the classical die
The
classic purification of biogas
To date, the purification of biogas is carried out mainly
for the valorization of biomethane by injection into natural
gas distribution networks of fossil origin.
The
diagram below shows the complexity of such a purification
plant comprising several treatment units and it will be noted
that the CO2, momentarily trapped, is released into the atmosphere.
Such installations represent a significant cost in terms of
investment and operation (costs of activated charcoal among
others).
PTC
System, innovating by its simple but particularly effective
technology, finds a preponderant place among current
purification techniques of biogas.
Purification of biogas with PTC System
It is the only known to completely eliminate in the same operation
and on a single unit of treatment CO2, N2, O2, H2O, H2S, NH3,
Siloxanes , Organochlorines or Organofluorines.
This
technology is the only one that does not require biogas compression
throughout the purification cycle and whose methane losses
will be less than 0.1%.
For biogas
resulting from the metering of the following inputs:
- Garbage
- Sludge
of Treatment Plant
- Disclaimer
Food
For biogas
derived from the mishandling of agricultural waste:
Biogas
from agricultural waste inputs producing between 50 and 100
mg / m3 of ammonia will be pretreated with a sulfuric acid
solution in the H2SO4 module.
The
"AciWash" module is intended for the capture
of H2S and other acidic compounds.
The
"AmiWash" module
produces high purity biomethane (> 98% CH4)
This biogas purification module consists of removing carbon
dioxide (CO2) once hydrogen sulphide (H2S) and other undesirable
acidic biogas compounds have been captured by the AciWash
module.
For this AmiWash proposes to put the biogas in contact with
a solution of amines in a physico-chemical absorption column
so that the carbon dioxide separates from the methane.
The implementation of a very selective reaction with carbon
dioxide makes it possible to obtain both a biomethane and
a high purity carbon dioxide after treatment with the AciWash
module.
The
"GasWash" module completes
the chemical modification of the compounds captured by the
AciWash module before the final destruction of the capture
products in the biological treatment plant.
The organic compounds present and formed during the condensation
reaction are digested by the aerobic bio-purification process
of the treatment plant.
See an example of
treatment
See the biogas treatment model
Biological
treatment of liquid effluents in wastewater treatment plants:
The
process according to the invention makes it possible to obtain
an absolutely odorless and colorless liquid treated product
which can be directly discharged to a self-neutralization
pond or a water treatment basin of a treatment plant, moreover,
acidification does not regenerate mercaptan, SO2 or hydrogen
sulphide.
Biological treatment in wastewater treatment plants does not
create any new nuisance either at the station itself or at
the level of the sewerage network.
The BOD (Biological Oxygen Demand) and COD (Chemical Oxygen
Demand) measurements are consistent with rejection standards
and improved compared to conventional oxidative destruction
processes.
Currently, what is the CO2 balance
of an anaerobic digestion unit ?
Each
m3 of biogas from anaerobic digestion helped to avoid the
release into the atmosphere of 2.3 kg of carbon
dioxide (CO2) responsible for global warming.
An anaerobic digestion unit of 2 MW, by the methanisation
principle, thus prevents the emission of about 9000 t of CO2
into the atmosphere.
However, it must be borne in mind that each m3 of biogas produced
always contains between 20 and 40% of CO2, ie between 3 kg
and 6 kg, which are finally released into the atmosphere,
or during biomethane purification by competing techniques,
either in the use of biogas without purification.
It should be noted that this same methanisation unit of 2
MW, which consumed about 4 Mm3 of biogas, still emitted between
800 t and 1,600 t of CO2 in the atmosphere depending on the
nature of the methanised substances.
The
composition of biogas and thus its impurities varies according
to the nature
Composants
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Ordures ménagères
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Boues de station d’épuration
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Déchets agricoles
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Déchets de l’industrie
agro-alimentaire
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CH4
% vol
|
50 - 60
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60 - 75
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60 - 75
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68
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CO2
% vol
|
38 - 34
|
33 - 19
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33 - 19
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26
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N2
% vol
|
5 -0
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1-0
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1 - 0
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-
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O2
% vol
|
1 - 0
|
< 0,5
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< 0,5
|
-
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H2O % vol
|
6 (à 40 ° C)
|
6 (à 40 ° C)
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6 (à 40 ° C)
|
6 (à 40 ° C)
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H2S
mg/m3
|
100 - 900
|
1000 - 4000
|
3000 – 10
000
|
400
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NH3 mg/m3
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-
|
-
|
50 - 100
|
-
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Siloxanes mg/m3
|
20 - 250
|
Traces
|
-
|
-
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Organochlorés ou organofluorés mg/m3
|
100 - 800
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-
|
-
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-
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An
INERIS report (15/12/2009) mentions carbon oxysulfide (COS)
concentrations in the order of 0.047 to 0.29 mg / m3 in biogas
from methanisation of sewage sludge.
Biomethane: Towards a cost of production
finally competitive ?
The
P.T.C. System is the only technology known to date, making
it possible to sustainably eliminate and recover CO2 from
methanisation in the form of carbonates, which is particularly
valuable in industry.
It allows the total capture, sustainable and in a single operation
of the CO2 but also of all polluting volatile compounds (N2,
O2, H2O, H2S, NH3, Siloxanes,
Organochlorines or Organofluorines).
The
P.T.C. System allows a cost of production of biomethane 3
times cheaper than the competition and therefore reduces the
cost difference between fossil-based methane and biomethane
to incorporate it into the network.
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The
valorization of biogas
Consisting mainly of methane and carbon dioxide, biogas is
efficiently recovered in biomethane
through purification processes.
This technique, called anaerobic digestion, is caused in digesters,
during the treatment of household waste, industrial or agricultural
waste and sewage
sludge.
Biogas, resulting from the fermentation of this waste, is
a source of renewable energy which after purification can
replace natural gas of fossil origin.
Farmers, industrialists and local authorities thus treat their
waste while enhancing their energy and economic potential.
The purification solution P.T.C. allows the valorization of
all biogas for the injection to the natural gas network, the
production of vehicle fuel (biomethane gas or liquid) or the
production of renewable hydrogen after reforming the biomethane.
The
purification technology by the P.T.C. System
In order to transform biogas into a substitute for natural
gas, it must be rid of all pollutants.
The P.T.C. System proposes a technical solution that today
allows biogas producers to use it effectively in biomethane
through its purification process.
The technology used makes it possible to eliminate carbon
dioxide (recyclable CO2) sustainably, and to eliminate in
the same operation N2, Siloxanes,
Organochlorines or Organofluorines.
The
hydrogen sector,
based on anaerobic digestion, should logically find its place
in the near future.
http://www.innovalor.fr/biogaz-biomethane.htm
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The
cycle of sustainable elimination of pollutants
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The
P.T.C. System is part of this new concept of purification
/ depollution.
This
system is currently the only known to permanently eliminate
CO2 and can be recycled in the
industrial sector.
In a period that is particularly conducive to the development
of alternative energies to fossil fuels, the prospect of integrating
biogas into the French energy landscape is of interest from
a political, economic and environmental point of view.
In
fact, the valorization of domestic, industrial and agricultural
organic residues or the treatment of wastewater meet the notions
of sustainable development and renewable energy, clearly explained
in recent international agreements and commitments.
The
environmental impact of the implementation of biogas recovery
channels results in a significant reduction in the greenhouse
gas emissions.
Recent
fluctuations in the costs of importing fossil fuels have also
positively influenced the renewed economic interest in energy
production from biogas, whether directly in the form of high
purity methane gas. or in the form of electricity.
The
cost price of biomethane completely purified by P.T.C. System
is 0.054 € / kWh. when the cost price in competing systems
is
0.15 €/ kWh.
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The
P.T.C. System allows a cost of production of biomethane
3 times cheaper than the competition and therefore reduces
the cost difference between fossil-based methane and biomethane
to incorporate it into the network.
On the other hand, the technology of P.T.C. allows extremely
simple biogas purification equipment whose investment cost
is incommensurate with the currently existing processes.
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