[0001] The thermal power plant invention for non-pelletized grape pomace biomass is used
for heat generation and hot water production for both individual and industrial consumers.
Winegrowers and single or multifamily housing units, guesthouses and companies in
wine-growing areas are the first categories of beneficiaries targeted by this invention
due to the existence of cheap and large quantities of grape pomace biomass. Also among
the possible beneficiaries are the owners of greenhouses and solariums who will be
able to heat large volumes of air with low costs and an almost zero carbon footprint.
[0002] Currently, there are a number of thermal power plants with burners that utilize biomass
in the form of pellets and a relatively small number of thermal plants that can use
non-pelletized biomass, but none that can burn this biomass in optimal yield conditions
and with minimal pollution in an almost raw, non-pelleted state, respectively the
grape pomace.
[0003] Although the existing thermal plants can also burn pellets or wood chips very well,
the main challenge, namely to be able to use the abundant and very cheap biomass represented
by pomace, remained unsolved.
[0004] A thermal power plant is currently known Patent of invention no.
RO 134 445 which refers to a thermal power plant and how to obtain and use thermal energy, by
burning solid fuels and biomass for the purpose of heating domestic, commercial, production
spaces, holiday homes, greenhouses and animal care spaces . The power plant, according
to the invention, uses water or air as a heating agent and consists of a main body
in which combustion takes place and a secondary body in which heat is exchanged, arranged
in a common enclosure surrounded by a jacket through which it circulates the heating
agent. The main body has a combustion chamber that features a telescopic mount at
the top, a fuel supply door and a combustion disc that rests on the burned fuel, an
air intake fan that forces air into the firebox through a connection that transfers
the hot fumes from the combustion chamber to the secondary body. It features a flue
gas collector and a hot gas recuperator equipped with a coil, making the water supply.
The collected fumes are evacuated by an exhaust fan, the circulation of the thermal
agent is ensured by a pipe and the return by another pipe.
[0005] A peasant thermal power plant for greenhouses is also known, invention patent no.
RO133992 (A2), which produces hot thermal agents, water and air, but also household water, intended
for rural households, being used for heating surfaces with solariums/greenhouses,
as well as shelters on farms for raising animals, but also for household utilities
The power plant according to the invention consists of a lower floor, equipped with
a combustion tank into which an air pipe enters, and with a solid fuel supply door.
Some heating sub-assemblies are connected to this lower floor, above which is axially
positioned a middle floor, in which there is a baffled sub-assembly, which is provided
with a tubular space delimited by an outer jacket and an inner jacket, and connected
with a tubular space of the lower floor. Above them, a last upper floor is mounted,
whose enclosures, a domestic water tank and a tubular enclosure with rock salt, are
heated by the hot air that rises from the middle floor through some pipes, and the
combustion tank is made up of a cylindrical pot, the access for cleaning the ash from
it is through a sliding door .
[0006] A solid fuel thermal power plant is also known, invention patent no.
RO133520 (A2), which consists of a vertical sheet steel heat exchanger, a secondary steel heat
exchanger, a chamotte vertical wall, a fuel inlet, a metallurgical cement insulation.
A base plate with a grate, an ashtray provided with an access hole and a door with
a draft adjustment slot, an enclosure with a connection for secondary intake air,
a primary intake air duct from the ash, a duct secondary intake air path from the
premises, a flow connection, a return connection, a connection for draining water
from the central unit, a smoke chamber with an inspection door. Constructively, a
thermal reaction loop is created which has the effect of triggering two processes:
the drying of the solid fuel, this allowing the power plant to be fed with wood with
high humidity, even 50%, and the self-heating of the solid fuel until reaching the
gasification temperature of at least 300 degrees°C, the process continuing to self-generate
through the thermal reaction loop, from its own energy resulting during combustion
until the fuel is exhausted.
[0007] All thermal power plants presented above have the disadvantage that they cannot ensure
the efficient combustion of the pomace biomass, which has a great calorific value
of approx. 5.8 KWh/kg (dry beech wood, usually taken as a benchmark, has 5 kWh/kg,
and category I pellets have 5.5 kwh/kg). As of now, it is very difficult to start
the ignition of the pomace, its combustion is difficult to control, and the residual
pollutant emissions are difficult to maintain within the limits provided by the European
regulations in force.
[0008] This invention solves the above technical problem by designing a thermal plant with
a
rotary burner equipped with a stainless-steel coil and self-cleaning for the burning of non-pelletized
biomass made of grape pomace resulting from the industrial pressing of grapes. This
rotary burner can generate a temperature of 600-800 degrees C at which the biomass
self-ignites and burns almost completely and uniformly.
[0009] The cylindrical shape of the burner and the automatic cleaning mode engaged by rotating
the basket burner by 6π with respect to the fixed cleanser make it possible for the
plant to break the lumps of silicates formed due to high temperatures and to empty
impurities, gravel or metals which would prevent the combustion of biomass.
[0010] The smoke circuits as well as the compartments of the thermal plant have been designed
to maximize the surface and the contact time between the hot exhaust gases and the
water in the jacket of the plant. This design maximizes the heat transfer and minimizes
the temperature of the exhaust gases which does not exceed 80 degrees C
[0011] To reduce the number of polluting particles, the emission gases are filtered through
a filter loaded with biomass of different granulations, coming from the same source
- the vine.
[0012] The constructive solution contains a Programmable Logic Controller (PLC) that controls
the complete combustion cycle of the plant.
[0013] Combustion takes place in a self-cleaning burner - a metal cylinder that can stand
high temperatures and has a thickness of 6-8 mm with holes of 5-6 mm as well as a
cut-out portion - the mouth of filling. The rotation of the burner basket by 6π with
respect to the fixed cleanser is done by an electric motor-reducer which, by means
of a pinion chain, drives a metal tube that tilts the burner basket. Inside this tube,
which rotates together with the with glow plugs and airburner basket, there is another
fixed metal tube, attached to the cleanser, which contains the glow plugs at one end
and a fan at the other end, that blows the primary combustion air over the glow plugs.
The other end of the cleanser is welded to one end of the stainless-steel coil that
sits in the flame and preheats the secondary combustion air.
[0014] A second fan blows air through this coil into the double-walled cleanser with 3-5
mm holes which combustion air is provided from all directions. As the coil heats up
to 600-800 degrees C the hot air now becomes the main air that provides combustion
and re-ignites the biomass without the need for glow plugs. The air blown through
the cooled glow plugs now reduces and becomes secondary air.
[0015] A feed auger driven by a gear motor takes the biomass from a vat and transports it
to the burner basket with glow plugs and air holes. The hot gases are directed through
the body of the plant to a metal cover that returns them through a system of pipes
that pass through a water-cooling jacket. When they reach the end of the pipes, the
hot gases reach another metal cover and are returned again through other pipes parallel
to the first ones that again pass through the jacket with cooling water, once again
giving up part of the caloric energy to the water in the plant.
[0016] Finally, the gases are discharged and cooled through the heat recovery unit to a
temperature lower than 80 degrees C.Finnaly, a cyclone-filter battery from where a
variable flow exhauster, takes them purified and discharging them into the atmosphere.
[0017] The filter has three layers of filter materials formed from biomass residues resulting
from the processing of grapes: the first layer, providing coarse filtration is located
in a cylinder of stamped sheet and consists of dried and chopped bunch residues up
to a maximum of 20 mm. The second medium filtration layer is located in a sheet metal
cylinder welded to the extension of the cluster screen and is made of 2-15 mm granulated
pomace. The cylinder filled with filter material has a ring welded to the upper part
with a sealing gasket that isolates another ring welded to the inside of the filter
housing. The last very fine filter layer contains a layer of 5-10 cm thick mineral
or welding wool. The degree of clogging is measured by a vacuum sensor that sends
the information through 4-20 V currents to the PLC that adjust the exhaust gases draft.
[0018] The door of the thermal power plant is made of thermally insulated metal, and has
some holes drilled for mounting the burner and the variable flow fans that blow air
through the coil and through the air tube containing the glow plugs. A metallic threaded
rod is fixed to the pinion and its free end periodically arrives near the proximity
sensor that regulates the position of the basket's feed opening. The filling of the
vat with biomass is switched on/off using another motor-reducer controlled by a level
sensor.
The invention presents the following advantages:
[0019]
- 1. There are larger vineyards with numerous wine producers worldwide and where large
amounts of pomace are found that are difficult to reintegrate into the environment
and neutralize. They can be observed all year-round decomposing under the open sky.
Only in Romania, for example, approx. 70,000 tons of pomace/year are produced with
an energy potential of 440 GWh, i.e. approx. 0.7 KWh for each liter of wine that is
produced. The thermal plant according to the invention can utilize this biomass.
- 2. The construction of the thermal power plant ensures optimal yield combustion with
minimal pollution of the pomace-type biomass in an almost raw, non-pelletized state.
- 3. This thermal plant effectively solves all these drawbacks with a near-zero C footprint.
[0020] An embodiment of the invention is given next in connection with figures 1 to 12,
which represent:
- fig 1 - general drawing of the thermal plant;
- fig. 2a, 2b - rotary burner assembly drawings;
- fig. 3 - feeding auger drawing;
- fig. 4 - burner basket image;
- fig. 5 - metallic coil image;
- fig.6 - cleanser with glow plugs and air holes drawing;
- fig. 7 - proximity sensor;
- fig. 8 - motor -reducer;
- fig. 9 - water flow sensor;
- fig. 10 a and 10 b - sections through the thermal plant;
- fig. 11 - diaphragm working positions drawing;
- fig. 12 - filter drawing
- fig. 13 - ash discharge system
[0021] The thermal plant is made up of the following main components according to (fig.
1):
- A the rotary burner with self-cleaning which is a constructive and functional innovation
(see more fig. 2a,2b,);
- B the body of the power plant which represents a constructive innovation;
- C heat recuperator ;
- D battery cyclone-oenofilter and which is a novelty of the filter material;
- E ash disposal system.
[0022] The cylindrical shape of the burner basket and the automatic cleaning mode by rotating
it by 6π with respect to the fixed cleanser make it possible to break the lumps of
silicates formed due to high temperatures and to empty impurities, gravel or metals
that prevent the combustion of biomass.
[0023] The smoke circuits as well as the compartments of the thermal plant have been designed
to maximize the surface and the contact time between the hot exhaust gases and the
water in the plant jacket, which maximizes the heat transfer as well as an minimizes
exhaust gas temperature in the atmosphere of maximum 80 degrees C.
[0024] C-through the heat recuperator, the fans that ensure combustion take hot air from
the recuperator, increase the efficiency of the plant, lower the temperature of the
gases discharged into the atmosphere and bring in air from outside the technical room.
The concentration of CO2 inside the technical room will not increase, unlike most
biomass thermal power plants because in this plant the combustion is done with air
from outside.
[0025] D-battery cyclone filter carries out exhaust gas filtration in two steps -a) the cyclone
makes a gravitational separation of the solid particles in suspension in the burnt
gases
- b) the filter cleans the gases coming out of the cyclone by passing them through the
filter material. The filter material is also composed of biomass. It is efficient,
cheap, ubiquitous in vineyards, with a minimal impact on the environment and consists
of successive layers of bunches of grapes and pomace. It can also be used as a standalone
filter for air or other gases. It has been successfully experimented with filtering
the syn-gas used in internal combustion engines, in which case a layer of ceramic
wool is added to protect the engine valves. This filter can also be used to filter
the air introduced from the outside inside the living spaces by adding in the final
layer filter plates that are common and cheap in the wine industry and can go up to
a grain size of 0.45 mm, that is to say it can be obtained pure, almost sterile air.
Description of the component parts of the burner (fig. 2).
[0026] The construction of the burner is made of a metal biomass vat (1) in which the pomace
is stored for distribution to the burner basket. A feeding auger (2) takes the biomass
from the vat (1) and transports it to the burner basket (3). The burner basket (3)
is a metal cylinder resistant to high temperatures with a thickness of 6-8 mm and
holes of 5-6 mm with a cut-out portion of the mouth of the basket ("a" in fig. 4),
through which the biomass supply is made at the beginning of the cycle when the mouth
of the basket "a" is positioned upwards as well as the discharge of ash and lumps
of silicates by repeatedly rotating the mouth of the basket "a" downwards.
[0027] The rotation of the burner basket (3) is done by the metal tube (14) which is rotated
by means of the pinion (5) by an electric motor-reducer (8).
[0028] An air blower (6) provides primary air by blowing air through the glow plugs (7)
during the ignition phase, but which provides secondary air during the burning phase.
[0029] In the overall construction of the burner there is also a stainless steel coil (9),
a cleaner (10), air nozzles (11), an access door to the burner chimney (12), an air
blower (13).
[0030] The glow plugs (7) that initially ignite the biomass are mounted inside the tube
(4).
[0031] The stainless-steel coil (9) secures and heats the combustion air supplied by the
fan (13) by directing it through the holes of the cleaner (10) into the basket of
the burner (3).
[0032] The cleanser (detail fig. 6) is a fixed metal part with double walls and with air
holes (11) which has a triple role:
- 1- clean the basket of the burner(3) from the inside when it rotates,
- 2- distribute the hot combustion air
- 3- maintaining the flame and re-igniting the biomass after the cleaning cycle without
the intervention of glow plugs .
[0033] The air nozzles (11) are holes made in the inner lining of the cleaner with a diameter
of 3-5 mm arranged around the biomass in the basket burner.
[0034] The access door to the burner (12) is metallic, thermally insulated and has some
holes "c" made for mounting the burner A and the fan (13) with variable flow that
blows air through the serpentine (9).
[0035] A metal threaded rod (15) rotates integrally with the pinion (5) fixed to the bearing
(16) and its free end periodically actuates the proximity sensor (17), which commands
the motor-reducer (8) to stop the bin with its mouth up for the next cycle of filling
after counting three spins of it.
[0036] The permanent filling of the tank with biomass (1) is done from an external big buffer
tank and is controlled by a level sensor (18).
[0037] The feeding auger (2) is driven by a gear motor (19).
[0038] The temperature in the flue area is measured by a thermocouple (20), and the temperature
of the burner basket by another temperature sensor (21).
[0039] The oxygen concentration in the burnt gases to regulate the air flow in order to
obtain an efficient combustion is measured with a lambda probe (22).
[0040] The temperature sensor (23) measure the heating agent and controls the rate of biomass
supply .
[0041] The commands are provided by an automation box with Programmable Logic Controller
(PLC) .
[0042] A water flow sensor (25) - measures the water presure in the pipes and the flame
sensor (47) gives an alarm if the flame in the burner is accidentally extinguished.
Both sensors can stop the biomasa supply when a fault occurs.
Functional description
[0043] The thermal power plant operates in combustion cycles with parameters constantly
adjusted by a PLC unit according to a logic scheme created especially for this kind
of burner.
[0044] A complete combustion cycle contains 4 phases: filling, ignition, burning and cleaning.
The filling phase
[0045] The PLC commands the motor-reducer (19) to fill the basket burner (3) with biomass
from the tank (1). The basket burner is positioned with the mouth upwards so that
it can be filled with biomass. Its position is regulated by the PLC using a proximity
sensor (17). Filling time is under 1 min.
The ignition phase
[0046] The PLC turns on the fan (6) and the glow plugs (7) until the biofuel in the stack
ignites. The initial ignition time mainly depends on the granulation and moisture
of the biomass being 3-5 minutes
Burning phase of the biomass
[0047] After the biomass has been ignited, the PLC commands the glow plugs (7) to be turned
off, the fan (13) to be turned on and the biomass basket to be permanently fed. The
air in the coil in the flame heats up between 400-800 degrees and is further used
as primary combustion air.. The flow rate of the fan (13) and the amount of biomass
are controlled by the PLC that processes the information from the sensors. To avoid
the formation of large lumps of silicates and other compounds that block combustion,
the time of the combustion phase is limited to no more than 17 minutes.
[0048] In the following cycles, thanks to the high temperature of the air in the coil whose
thermal inertia has been increased by filling it with ceramic balls, the biomass can
also re-ignite by itself, without the need to restart the glow plugs. This fact reduce
energy consumption and extending their life.
Emptying/cleaning phase - cleaning
[0049] The programmed burning time is until 17 min. After this time, the PLC stops the fans
and the pomace supply, then commands the 6π rotation of the burner basket for cleaning
and the gravitational evacuation of ash and other combustion residues, and restarts
combustion cycle until the desired temperature of the thermal liquid set by the user
in the PLC.
Description of the thermal power plant
[0050] The thermal plant shown in section in fig. 10a and 10b was designed to extract as
much heat as possible from the energy produced during the combustion of the biomass
by increasing the surface area and contact time between the flame with the hot exhaust
gases on the one hand and the water in the cooling jacket (26) on the other part.
Biomass burning takes place inside the compartment (27) and the flame and hot gases
are directed through the body of the plant to the cover (28) from where they are returned
through a pipes system (29) that pass through the water jacket (26) and this part
of the heat. After reaching the compartment bounded by the covers (30) and (31), the
gases are returned again but through the pipes (32) which are partially immersed in
the water jacket (26) and reach the compartment bounded by the covers (28) and (33)
) being forced to escape through the pipes of the heat recuperator C .
[0051] For a more complete combustion, the gases are directed by the metal diaphragm with
a variable angle in fig. 11 to reach the hot refractory surface (34) on which the
ash falls from the burner basket (3) and where the thermal decomposition (pyrolysis)
of the last traces of organic matter takes place ( especially from the oleaginous
seeds present in the pomace), followed by their burning. Before leaving the thermal
plant, the gases pass through the heat recovery unit C cooled by the air captured
from the outside by the blowers that provide the oxygen necessary for combustion.
The gases thus cooled to a temperature lower than 80 degrees C are discharged through
a cyclone (35) and a filter (36) (Oeno-filter-cyclone battery fig.12) by an exhauster
(37) with adjustable flow also controlled by the PLC.
[0052] For the production of domestic hot water (DHW), the boiler is equipped with an auxiliary
recirculation pump that takes a fraction of the hot water from the boiler circuit,
heats a coil boiler and then returns the cooled water through the boiler return. Thus,
the water cooling jacket of the plant (26) constitutes a caloric energy buffer from
which the DHW boiler can be fed - domestic hot water even during the summer, the process
also being directed by the PLC logic unit.
Description of the Oeno-filter
[0053] This filter (36) in fig.12 has as a novelty the composition of the filter material
which is made up of biomass residues resulting from grape processing. This fact ensures
an extremely low cost but also environmental protection because the filter material
is also finally burned in the plant (except for the last layer of mineral wool) and
is not constituted as waste.
[0054] The first layer, of coarse filtration, is located in a stamped sheet metal cylinder
sieve (38) and consists of remains of dried and chopped bunches up to a maximum of
20 mm that form sinuous smoke channels. This channels cause unburned tars and suspended
particles to stop in this labyrinth.
[0055] The amount of filter media depends on the desired filter capacity (36).
[0056] The second layer, of medium filtration, is located in a welded sheet metal cylinder
(39) in the extension of the sieve with clusters and is made of pomace with a grain
size of 2-15 mm as it results directly from the sorting phase. This being denser than
the clusters creates sinuous channels of smaller sections and will retain medium and
small particles as well as other volatile substances that have escaped from the burner
and the coarse layer of clusters.
[0057] The filter cylinder has a ring (40) with a seal (41) welded at the top which seals
to another ring (42) welded to the inside of the filter housing (36).
[0058] Both filter materials, after being loaded with tars and particles that have escaped
unburned, are introduced into the plant's burner and burned together with the current
biomass, so they do not constitute waste
[0059] In order to obtain a last very fine filter layer, but also for a quick visual control
of the degree of retention of pollutants by the filtering biomass, a layer of approx.
5-10 cm thick mineral or ceramic wool is placed. The degree of clogging is measured
by a vacuum sensor (43) that sends the information via 4-20 V currents to the PLC
for draft regulation. A battery of two filters can be used that can be alternately
changed without having to turn off the boiler, in which case the vacuum sensor (43)
is mounted on the common filter gas supply pipe.
[0060] The filter can also be used for the air in habitable rooms of medium and large volumes,
having also been tested for industrial gases such as syn-gas produced from the same
biomass described above.
Ash disposal system
[0061] The evacuation of the ash is realized with the help of a flexible metal auger (44)
operated by an electric motor-reducer which transports it into a closed metal collector
45 as schematically illustrated in fig.13.
- Oenology is the science that deals with the study of vines and wine and their by-products,
that's why we considered it appropriate to introduce the prefix oeno considering that
grape pomace and filter material come directly from this field.
- • The energy consumption for the production of one liter of wine from the reception
of the grapes to bottling is calculated by the author to be about 0.04 KWh, from which
it follows that the winemaking of grapes can be transformed from an energy-intensive
process (17 GWh in 2023 only in Romania and over 1000 GWh worldwide) in an energy-generating
process.
- • The grape pomace contains several types of combustible substances that contribute
to a high energy value of approx. 5.8 KWh/kg, namely cellulose, lignin, oil, sugar,
traces of alcohol, etc.
- • the pomace must be prepared for energy recovery - a stage that consists in drying
and sorting the biomass (which already results in granulated form from the process
of pressing the grapes in pneumatic presses). For a maximum yield, biomass with dimensions
of no more than 15 mm and humidity of no more than 10% is burned. Drying can be done
in dryers or, in the case of small and medium consumers, simply in the sun on concrete
platforms (approx. 30 tons/ 1000 m2 x season).
1. Thermal power plant for non-pelletized grape pomace biomass consisting of a main body, having a combustion chamber in which the combustion is
carried out and a secondary body in which the heat exchange is carried out, characterized by the fact that a unit Programmable Logic Controller (PLC) ensures control of a complete
combustion cycle of the thermal power plant made of a self-cleaning burner (A), in
which a stainless steel coil (9) enters to heat the primary combustion air supplied
by a fan (13) directing it through some nozzless of a fixed cleaner (10) into the
basket (3) of the burner in the form of a metal cylinder able to stand high temperatures
with a thickness of 6-8 mm and holes of 5-6 mm and with a cut-out portion (a) the
mouth of the basket, which can be rotated with 6π with respect to the fixed cleaner
(10), a feed auger (2) driven by a gearmotor (19) takes the biomass from a tank (1)
and transports it to the burner basket (3), the burning of the biomass is done in
a compartment (27) and the flame and hot gases are directed through the boiler body
(B) to a cover (28) from where through a system of pipes (29) they pass through a
water cooling jacket (26), reach a compartment bordered by some covers (30) and (31)
are directed through some pipes (32) which are also immersed in the water cooling
jacket (26), arrive in the compartment delimited by the covers (28) and (33) being
discharged through the pipes of the heat recovery unit (C), the cooled gases at a
temperature lower than 80 degrees C are discharged through a cyclone (35) and a filter
(36) which has three layers of filter material formed from biomass residues resulting
from the processing of grapes, by an exhauster (37) with adjustable flow, the ash
evacuation is realized with the help of an flexible auger (44).
2. Thermal plant for non-pelletized grape pomace biomass according to claim no. 1, characterized by the fact that the tilting of the basket burner (3) is done by the motor-reducer (8)
which drives the pinion (5) which rotates the metal tube (14) through a chain into
which the basket burner and a fan (6) blows the main air through two glow plugs (7)
during the ignition phase, the cleanser (10) is a fixed metal piece with double walls
and air nozzles (11), with 3-5 mm holes made into the inner wall, and arranged around
the biomass contained in the basket burner (3), the central door of the thermal plant
(12) is thermally insulated and has some holes (c) practiced for mounting the burner
(A) and the variable flow fans (13) that blow air through the coil (9), the glow plug
air tube (4) is a fixed metal pipe that enters the metal tube (14) and contains the
glow plugs (7) of ignition which guides the hot ignition air to the basket burner
(3), a metal threaded rod (15) is fixed to the pinion (5) through the free end that
periodically comes close to the proximity sensor (17) which regulates the position
of the feed mouth of the basket, stopping/starting the filling of the vat (1) with
biomass is controlled by a level sensor (18).
3. Thermal plant for non-pelletized grape pomace biomass according to claim no. 1, characterized in that the filter (36) has as a filtering element for a composition of biomass residues
resulting from the processing of grapes, the first layer of coarse filtration is located
in a cylinder (38) of a stamped sheet metal and consists of dry bunch residues chopped
up to a maximum of 20 mm, the second, medium filtration layer is in a sheet metal
cylinder (39) welded into the extension of the bunch sieve and is made of pomace with
a grain size of 2-15 mm, the filter material cylinder has a ring (40) welded to the
top with a sealing gasket (41) that seals another ring (42) welded to the inside of
the filter housing (36), a last very fine filter layer contains a layer of approx.
5-10 cm thick mineral wool, the degree of clogging is measured by a vacuum sensor
(43) which sends the information using electrical currents of 4-20 V to the PLC for
regulating the draft.