DE102021001543A1 - Closed atmosphere dryer - Google Patents

Abstract

The invention relates to a dryer (1, 23, 24) with a closed atmosphere for separating the volatiles. Mixtures of. Water and low boilers. Sewage sludge in a heating circuit (7). This is achieved by having a pipe (12) for mixtures of the distillates, an absorber (13, 18) for a binary mixture of NH3 and water H2O, in which one heat exchange medium is water and the other heat exchange medium the distillates from sewage sludge are provided and a feed line for the cold water H2O. (14, 19) This makes it possible to avoid the hotspots of sewage sludge mono-incineration when drying sewage sludge in a transport container (1, 23, 24) for investments in immissions-free and CO2-free objects.

Description

The invention is concerned with dryers in a closed atmosphere for the separation (separation) of water and low boilers from sewage sludge in order to demonstrate the separation of ammonia, NH3 from sewage sludge in the production of dry matter, to produce sewage sludge with little NH3 and the climate from climate gases such as CO2 and nitrous oxide N2O formed when burning NH3 with water to relieve.

The invention also deals with the goals of the climate summit in Glasgow to limit immissions to global warming of 1.5 ° C.

Recently, international corporations (Swiss Re Group) in the field of climate protection have learned that big goals in the investment portfolio are no longer enough, just as important is participation in the real economy, for the development of climate protection strategies. More details: Swiss Re publishes high climate targets; accelerates Race to net zero; March 16, 2021 / Christian Mumenthaler / Zurich and Guido Fürer. In the case of the investment, it is accordingly the case that the investments are intended as immissions-free and CO2-free objects.

For the reduction of ammonia NH3, which is harmful when burning with H2O, a law according to VO 641.711 from Switzerland is known, according to which the greenhouse gases CO2 and other climate-damaging gases, such as the nitrous oxide N2O formed when burning NH3, are identified with 298 times the CO2eq equivalent are. Accordingly, according to the current climate protection strategy, sewage sludge incineration plants are also affected because of the additional high immissions of climate-damaging gases from NH3 and further measures and investments are necessary for sewage sludge.

Furthermore, Switzerland's climate goals are named in the Energie Zukunft Schweiz magazine, according to which new concepts and new business cases with ambitious goals for Switzerland are addressed so that zero emissions and the use of limited resources are made possible in Switzerland's climate protection. (Energy Future Switzerland, Dec. 2018, Vincent Eckert, Swiss Re, Management Ltd, Adliswil). Accordingly, especially in Switzerland, with the most harmful, additional greenhouse gases from NH3 combustion, further measures are necessary.

The FOEN also knows about the reduction of the most harmful greenhouse gases, according to projects no.0117 and no.0159 in the Emmen sewage treatment plant by 2020, in less than 4 years 40,000 Mg CO2eq from nitrous oxide N2O during the incineration of sewage sludge in an after-treatment by a thermal fission at 960 ° C with 10,000 Mg CO2eq per year - net - to have eliminated. Accordingly, using the example of Zurich at 1,500,000 PE for the additional immission of (10,000 / 220,000 * 1,500,000) 68,181 Mg CO2eq per year, further measures are necessary. See example: below.

Disadvantage: the climate costs for additional CO2 immission, almost 800 times the level of the NH3 measured value: More details in the example: see below
68,000 Mg x 100 CHF = 6,800,000 CHF per year, to be paid from 2015, the start of sewage sludge incineration.

From this mono-incineration of sewage sludge in Zurich Werdhölzli it is known that 3.750 mg of NH3-containing sludge, together with 5 mg of water, H2O are burned every hour. Disadvantages are: global warming due to the displacement work p (v "- v ') of 5,000 kg steam, the immission of 40,000 Mg steam / a and the generation of the worst climate gas, namely nitrous oxide N2O in the amount of 68,181 Mg CO2eq documented by the FOEN 7 times the ARA Emmen Disadvantage: the hotspot of climate-damaging emissions near the city center.

Significant disadvantages: The hotspot with the additional immissions and consequential immissions costs due to the intake of sewage sludge from 1,100,000 PE from outside Zurich. The disadvantage is the devaluation of real estate and land in the hotspot, private and public, according to the state of the art (Swiss re). Example: 50 CHF / m2 for 84.7 km2 (84,700,000 m2 x 50 CHF / m2) 4,235,000,000 CHF depreciation due to inner-city, central sewage sludge incineration.

There is also a proposal for global climate protection from WEF Davos 2020, known to reduce the risks to the world economy due to climate change by “planting trees” by multiples of 1,000,000,000 trees in order to separate CO2 gases; with a disadvantageous area requirement of 1 ha, for 13 Mg CO2 integration per year. Major disadvantage: lack of land as well as the supply of Sewage sludge of 1,100,000 PE from outside Zurich city, formation of hotspots at the headquarters of the insurance companies (Swiss Re).

One method for drying a moist sewage sludge is from the publication CH 644 683 known from SULZER-Escher Wyss AG, according to which the water is separated from the sewage sludge as a distillate at boiling point and the distillate is then condensed. Further measures are necessary to limit immission from mono-incineration and to reduce hotspots.

Furthermore, a guideline for the treatment of immissions is known from the amended TA Luft from March 26th, 2021 (draft resolution), according to which an avoidance of immissions in the treatment of sewage sludge in the 4-country corner, Germany, Austria, Liechtenstein and Switzerland is possible and necessary is.

The invention specified in claim 1 for more climate protection in the treatment of sewage sludge according to the state of the art in Switzerland, in which the most harmful greenhouse gases occur in mono-incineration and further emissions occur in the city center through the supply of sewage sludge, lies in the resulting consequential damage and Follow-up costs in Zurich are based on the problem of proposing a solution for separating the ammonia from the sewage sludge for drying the sewage sludge in order to separate NH3 from the sewage sludge with zero emissions, to avoid the formation of CO2eq emissions as N2O in the incineration and investments in To enable CO2-free areas without global warming and real estate and buildings. Another task is to avoid the delivery of moist sewage sludge to the metropolitan areas and additional immissions in the hotspots.

This problem is solved by the features listed in claim 1, of dryers with a closed atmosphere for separation (separation) of water and low boilers from sewage sludge as distillates, in which a pipeline is provided for discharging the excess of distillates, an absorber for the distillates from NH3 and water H2O is provided, in which a heat exchange medium and sorbent are water and the sorbent are the distillates from the sewage sludge,
and the sorbent is provided for sealing off the atmosphere, and in particular a feed line for water and a withdrawal line for sorbate are provided.

Advantageous further developments and embodiments of the invention are possible through the measures mentioned in dependent claims 2 to 8.

The advantages achieved with the dryer in a closed atmosphere consist in climate protection and in the separation of the NH3 from the moist sewage sludge - instead of the splitting of N2O at 960 ° C - and in the saving of global warming through the displacement work p (V "- V ') of water vapor and the immission from water vapor.

• ◯ Klärschlamm Trocknung dezentralisiert;
• ◯ Null (zero) Immission aus dem Trockner;
• ◯ Keine Werteminderung von Grund, Boden und Immobilien durch Immissionen;
• ◯ Erfüllung des CO2 Gesetzes VO 641.711 der Schweiz;
• ◯ Vermeidung der Folgekosten für CO2 - 68.000 Mg/a in Zürich;
• ◯ Vermeidung der zentralen Verbrennung und der Hotspots in den Städten.

Other advantages:

• ◯ decentralized sewage sludge drying;
• ◯ zero immission from the dryer;
• ◯ No depreciation of land, land and real estate due to immissions;
• ◯ Fulfillment of the CO2 law VO 641.711 of Switzerland;
• ◯ Avoidance of the follow-up costs for CO2 - 68,000 Mg / a in Zurich;
• ◯ Avoidance of central combustion and hotspots in cities.

An essential feature of the invention, with a pipeline for draining off the excess of distillates, is to drain the distillates formed from the sewage sludge. Achieved advantage: NH3 discharge integrated into the drying process.

Another feature of the invention is the sorbent to seal off the atmosphere. The advantage is that the liquid is 100% sealed against gas penetration and a condensation stage is formed when vapors enter; Essential advantage: Saving of energy without the work of displacement p (v "- v ') of water vapor (v"), without hotspot.

An advantageous embodiment of the invention is specified in claim 2. The development according to claim 2 makes it possible to provide a feed line for water and a withdrawal line for sorbate. The benefit achieved is: Features of batch operation as well as recycling of energy and integrated treatment of NH3.

An advantageous embodiment of the invention is specified in claim 3. The development according to claim 3 makes it possible to provide a heating circuit on the dryer. The advantage is the use of various types of waste heat, from flue gases, digester gases, salt, energy storage and methane, ketones, electrical as heating.

An advantageous embodiment of the invention is specified in claim 4. The development according to claim 4 makes it possible to provide a fan on the absorber. The advantage: plant security and transport security of operating volumes.

An advantageous embodiment of the invention is specified in claim 5. The development according to claim 5 makes it possible to provide an absorber with several separation stages. Advantage: batch operation and several absorber levels. Significant advantage: increased separation efficiency of NH3.

An advantageous embodiment of the invention is specified in claim 6. The development according to claim 6 makes it possible to provide a disposal line for sorbates in the macaw. The condensate of the distillates in the heated sorbates in the Ara (sewage treatment plant) can advantageously be used. Advantage: zero emissions with 100% recycling of waste heat with integration of the NH3.

An advantageous embodiment of the invention is given in claim 7 with dryers in a closed atmosphere for separation (separation) of water and low boilers from sewage sludge as distillates, in which a transport container is provided for dry material, a pipe is provided for discharging the excess of distillates, a Absorber for the distillates from NH3 and water H2O is provided, in which a heat exchange medium and sorbent water and ammonia and the sorbent are the distillates from sewage sludge and the sorbent is provided for a closure of the atmosphere. The advantage achieved: The container net area of 13.88 m2 for a 20 'container and the net area consumption of (2 x 13.88) 27.76 m2 for one container at the filter press and one in the drying station. The main advantage: the space required when integrating the NH3 separation.

• 1 Trockner bei geschlossener Atmosphäre

An advantageous development of the invention is given in claim 8 for transport containers with nozzles for hot gases, inflow floors for dry material and outlet nozzles for gases used for integration into the circuit. The advantage achieved: simplicity, drying and NH3 separation with little staff required. This is because if the container from the filter press is filled over 24 hours, then no personnel is required. Further advantages of the climate-positive invention are shown in the drawing 1 shown and described mathematically in examples. Show it:

• 1 Closed atmosphere dryer

• • eine Trennung von NH3 bei 100 °C, 133 °C über dem Siedepunkt möglich ist, im Transportcontainer bei Null Emission;
• • Erderwärmung entfällt, keine Verdrängungsarbeit P(v" - v') von Dämpfen, kein Hotspot durch Klärschlamm;
• • Abwärmen zurückgeführt und Primärenergie gespart wird;
• • Klimapositivität der Anwohner möglich ist, wenn die Kondensation der überschüssigen Destillate als Energiegewinn möglich ist;
• • Verringerung des Hotspot Zürich um 1.100.000 EW;
• • Ein dezentraler Flächenverbrauch aus 2 x 13,88 m2 für 2 Containerstellplätze vorgesehen ist;
• • Wasser-Kreisläufe und Pumpen durch die Bauweise der Quench Kühler nach F28C 3/06 gespart sind;
• • eine Summierung der CO2 Gutschriften aus der Vermeidung der CO2 Emission und des Hotspot möglich ist.

A dryer integrated into a circuit is in 1 Shown as a scheme that comes from a dryer 1 , constructed from a transport container on wheels, an inflow base 2 for receiving sewage sludge, fed from a chamber filter press, a filling 3 with sewage sludge on the inflow tray 2 , a free space 4th , a blanket 5 of the container 1 , from a nozzle 6th for a feed of heated gases from a circuit 7th , from a nozzle 8th in the cycle 7th leading out of a fan 9 , a device 10 for dust separation, from one heating stage 11 with the continuing pipeline in the circuit 7th , from a releasable connection on the nozzle 6th , a further releasable connection on the nozzle 8th and for the discharge of excess distillates from the dryer 1 , from a sampling line 12th to an absorber 13th , in the version as quench cooler, with a task line 14th for cold water and a withdrawal line 15th of the water heated by steam condensation, from further lines 16 , a fan 17th for sucking off excess distillates, an absorber 18th for the absorption of low boilers NH3 in cold water, with feed lines 19th and a removal line 20th as well as a pressure measuring point 21 with an electronic connection 22nd to the speed-determined delivery volume of the fan 17th for a controlled operating pressure at the measuring point 21 , a regression 26th the non-condensable is constructed in such a way that

• • a separation of NH3 at 100 ° C, 133 ° C above the boiling point is possible, in the transport container with zero emissions;
• • There is no global warming, no work of displacement P (v "- v ') of vapors, no hotspot from sewage sludge;
• • waste heat is recycled and primary energy is saved;
• • Climate positivity of the residents is possible if the condensation of the excess distillates is possible as energy gain;
• • Reduction of the Zurich hotspot by 1,100,000 inhabitants;
• • A decentralized space consumption of 2 x 13.88 m2 for 2 container spaces is planned;
• • Water circuits and pumps are saved due to the design of the quench cooler according to F28C 3/06;
• • It is possible to add up the CO2 credits from avoiding CO2 emissions and the hotspot.

Major advantage: Integration of the NH3 separation in the transport container, without the formation of nitrous oxide N2O, without hotspot.

Next is in 1 a bypass pipeline 25th for setting a constant flow in the circuit and an underframe 23 on wheels 24 shown, whereby the transport container is displaceable.

In addition to the representation in 1 with the discharge of the excess gases there are other connections of the pipeline 12th possible, which are not listed in detail. It is important that excess gases are diverted from the circuit via the transport container so that the advantages of plant safety, personal protection and explosion protection remain. The advantage is: The security of the integrated separation of NH3 up to 100 ° C through the connection of the transport container.

Further advantages of the invention are shown as an example for sewage treatment plants that work without thermal decomposition of N2O and without nitrous oxide formation from NH3, with the savings compared to the prior art: FOEN - nitrous oxide project No. 0117 Emmen CO2 reduction according to the law VO 641.711 CH Elimination of CO2eq emissions from nitrous oxide N2O Mono-incineration in sewage treatment plant Emmen near Lucerne Great Emmen 220,000 pe Priority at the FOEN, submission of the application December 19, 2014 investment 3,000,000 CHF Amortization via CO2 payment in the first year 2015 Nitrous oxide separation in 4 years as CO2eq, net 40,000 Mg / a Funding / remuneration 3,000,000 / 10,000 t-net 300 CHF / Mg CO2eq, net Savings for Zurich, allocated area 84.7 km2 Reference area of the sewage treatment plant 8,470 ha Sewage treatment plant with mono-incineration Werdhölzli Commissioning, with nitrous oxide from NH3 August 2015 Nominal CO2 immission: 10,000 * 1,500,000 / 220,000 PE 68,181 Mg CO2eq / a Climate damage through CO2 68,181 Mg CO2 / a Mud dry 30,000 / 8,000 3.75 mg / h Evaporation 40,000 / 8,000 5 mg / h Global warming through displacement work - 40.5 kcal / kg p (v "- v ') Geothermal heating 235 kW * 8,000 1,883 MWh / a Untreated quantity from the Emmen project - net 68,000 Mg CO2eq / a Major disadvantage: Hotspot Zurich Immission pollution on 8,470 ha 84,700,000 m2 Financial loss at 50 CHF / m2 4,235,000,000 CHF Avoidance of damage: from sewage sludge incineration near the city and the sludge supply of 1,100,000 inhabitants from outside in the hotspot Zurich. Sewage sludge drying after 1 Savings, shown using the example of Lindau (B) Sludge feed via pump and Chamber filter press Nominal amount, dry 2.7 mg / d Nominal water volume - 68% 5.9 mg / d Feed wet 8.6 mg / d Required space for 8.6 mg of wet sludge (1) 20 'container Net space requirement according to DIN 13.88 m2 Calorific value Ho at 2,500 kcal / kg 10,450 kJ / kgTs Drying at 100 ° C with distillates: Heat requirement 5,900 kg * 2,215 kJ 13,070,000 kJ / d Nominal cycle - distillates 16,000 kg / h Nominal heat emission delta T 90 ° C Nominal dryer output 16,000 * 0.46 * 90 ° C * 4.18 2,768,000 kJ / h Nominal operating time 13,070 / 2,768 4.7 hours of operation Operating time / nominal hours 365 * 4.7 1,715 hours / a Main advantage: distillates with high specific heat Nominal data Lindau sewage treatment plant It's on, 10 mg sludge / d Disposal by road transport, for thermal disposal Specific costs 330 € / mg sludge Savings 3,300 € / d * 365 days € 1,204,500 / a With the following savings, Economic goods made from dry sewage sludge 2.7 Mg / d - NH3 free Energy storage at Ho 10,450 kJ / kg 7,848 kWh / d Heat price of € 0.03 / kWh 235 € / d 365 days a year € 86,000 / a CO2eq * Avoidance according to Swiss law - gross 0.1 Mg CO2eq / inhabitant and others 45,000 PE using Lindau as an example, gross * 4,500 Mg CO2eq / a Amount of savings at 100 € / Mg CO2 450,000 € / a Savings from calorific values € 86,000 / a From current costs € 1,204,500 / a Total savings - without hotspots - 1,740,000 € / a *) These values have been confirmed several times by NH3 diagnoses in SULZER absorbers within the scope of acceptance reports, including from (13th - 24th) October 1982 in Kyoto.

• Klimaschutz nach dem Stand der Technik (Swiss Re), Dezentralisierung der Klärschlamm Trocknung, Entlastung von Klimagasen von 1.100.000 EW in Zürich, Vermeidung von Wertverlusten bei Immobilien und Verringerung der Hotspots.

Achieved advantages in climate protection for Switzerland:

• State-of-the-art climate protection (Swiss Re), decentralization of sewage sludge drying, relief of climate gases from 1,100,000 inhabitants in Zurich, avoidance of loss of value in real estate and reduction of hotspots.

Significant advantage, the physical material data used: The boiling point of NH3 at - 33.34 ° C; The evaporation pressure at 100 ° C in anhydrous sewage sludge; Displacement work 169 kJ / kg steam at 100 ° C according to E. Schmidt; NH3 absorber several separation stages at lower temperatures. The result achieved - Integration of the NH3 evaporation at </ = 100 ° C. - Zero emissions of CO2eq from NH3.

Improvement in climate protection:

Avoidance of the hotspots of mono-incineration of sewage sludge.

List of reference symbols

1

dryer

2

Inflow tray

3rd

Filling with dry goods - filling quantity

4th

free space

5

Ceiling of the container

6th

Connection for hot gases

7th

Circuit, hot for gases

8th

Outlet nozzle, for gases used

9

fan

10

Dust separation, device for ...

11

Heating level

12th

Pipeline, extraction line

13th

absorber

14th

Feed line

15th

Water extraction line

16

continuing management

17th

fan

18th

Absorber for NH3

19th

Supply lines

20th

Removal of line

21

Pressure measuring point

22nd

electronic connection

23

Underframe

24

bikes

25th

Bypass pipeline

26th

Return, conduction

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• CH 644683 [0011]

Claims (8)

Closed atmosphere dryer for separation (separation) of water and low boilers from sewage sludge as distillates, whereby (1) a pipe (12) is provided for discharging the excess of distillates, (2) an absorber (13) is provided for the distillates from NH3 and water H2O, in which a heat exchange medium and sorbent are water and ammonia and the sorbent is the distillates from sewage sludge, (3) and the sorbent (sorbent) is provided for a closure of the atmosphere. Dryer according to the above Claim 1 , a feed line (14) for water and a withdrawal line (15) for sorbate being provided. Dryer according to one of the preceding claims, wherein a heating circuit (7) is provided on the dryer (1). Dryer according to one of the preceding claims, wherein a fan (17) is provided on the absorber (13). Dryer according to one of the preceding claims, wherein an absorber (13, 18) with several separation stages is provided. Dryer according to one of the preceding claims, wherein a disposal line (20) for sorbates is provided in the macaw. Dryer in a closed atmosphere for separation (separation) of water and low boilers from sewage sludge as distillates Claim 1 , whereby (1) a transport container (1, 24, 25) is provided in a closed atmosphere, (2) a pipe (12) is provided for discharging the excess of distillates, (3) an absorber (13) for the distillates from NH3 and Water H2O is provided, in which a heat exchange medium and sorbent water and ammonia and the sorbent are the distillates from sewage sludge, (4) and the sorbent is provided for a closure of the atmosphere. Dryer according to the preceding claim, with nozzles (6) for hot gases, inflow bases (2) for dry material (3) and outlet nozzles (8) for gases used for integration in the circuit (7) being provided in transport containers (1, 24, 25) are.

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