EP3694624A1 - Système de séparation d'une installation de désulfuration de gaz de combustion d'un navire - Google Patents

Système de séparation d'une installation de désulfuration de gaz de combustion d'un navire

Info

Publication number
EP3694624A1
EP3694624A1 EP18779619.8A EP18779619A EP3694624A1 EP 3694624 A1 EP3694624 A1 EP 3694624A1 EP 18779619 A EP18779619 A EP 18779619A EP 3694624 A1 EP3694624 A1 EP 3694624A1
Authority
EP
European Patent Office
Prior art keywords
chimney
separation system
flue gas
lamella
drops
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP18779619.8A
Other languages
German (de)
English (en)
Inventor
Detlef Weber
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP3694624A1 publication Critical patent/EP3694624A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D45/00—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces
    • B01D45/04—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by utilising inertia
    • B01D45/08—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by utilising inertia by impingement against baffle separators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/32—Arrangements of propulsion power-unit exhaust uptakes; Funnels peculiar to vessels

Definitions

  • the invention relates to a separation system of a flue gas desulphurisation plant of a ship.
  • this separation system should ensure that ships equipped with this system meet the requirements of the new emission regulations at sea.
  • this separation system should overcome the known problem of chimney rain (heavy drop ejection from a wet chimney).
  • this separation system taking into account the operational experience of recent decades, the pollution of the droplet (the flue gas flow direction) following components reduce, if possible minimize.
  • Flue gases from diesel-fueled marine engines are desulphurized predominantly by the wet scrubbing process for exit from a chimney.
  • the sulfur-containing flue gas is passed through a container which is located in the flue gas flow direction in front of the chimney.
  • the sulfur-containing flue gas is sprayed with seawater (suspension solution) and the S0 2 located in the flue gas bound in the spray drops of this suspension solution.
  • seawater suspension solution
  • S0 2 located in the flue gas bound in the spray drops of this suspension solution.
  • the larger spray droplets collect in a sump arranged below the inlet due to gravity to wastewater, which can be purified in further process steps, smaller of these spray droplets are entrained by the gas stream.
  • the separation system separates the droplets and optionally also dry solids from the flue gas stream, in which it deflects the latter several times in the separation system by means of flow resistances.
  • the drops and the dry solids are exposed to centrifugal forces. They can not follow the flue gas in its path, but bounce off the flow resistances that cause the diversion of the flue gas flow, also referred to as "baffles.”
  • the drops are thereby deposited on these baffles and thus removed from the flue gas flow
  • the separation systems regularly comprise packets of plate-like and curved deflecting bodies, these regularly rigidly suspended deflecting bodies being usually configured in such a way that channels are formed The aim of this configuration is, on the one hand, to cause a strong diversion of the flue gas and, on the other hand, to minimize "blockage" of the flue gas path by flow resistances.
  • the baffles or deflection bodies are also generally called “lamellas", the impact bodies correspond to “lamellar separators” or else only “lamellas.”
  • the common lamellas of the various manufacturers differ in terms of geometry, lamella spacings, deflection and design (" Roof “,” flat “or” horizontally “flowed).
  • the chimney rain is also caused by a breakthrough from the separation system.
  • Cracking means that the droplets leave the separation system on the downstream side, either because the separation system does not work (contamination, incorrect configuration or excessive flue gas velocity), or because the washing of lamellae causes the break-through of washing drops and breaks through the separation system.
  • the drops of the chimney draft are on the one hand rather acidic, since sulfuric acid is present in them, on the other hand, these drops have a high solids content.
  • the sulfuric acid comes from the combustion process in the diesel engine. Sulfur-containing diesel was burned and, accordingly, the content of S0 2 and some S0 3 in the flue gas is relatively high.
  • the liquid is a dilute sulfuric acid and accordingly highly aggressive and corrosive. The solid becomes, since with washing the accumulated Melten solids enter the liquid and then run mostly, to a small extent but also entrained.
  • these drops which then fly out of the chimney and into the surroundings, lead to clearly visible contamination on the ship's walls and surfaces.
  • a oily slat only works very limited.
  • the oil prevents the build-up of a water film on the lamellar surface.
  • this film of water is very important because it absorbs and binds the approaching drops.
  • the drop to be deposited hits a surface which has become oily, it will burst and be thrown back into the flue gas stream, instead of being deposited in the water film or on the surface of the lamella. It creates so-called secondary spray. The just deposited drops are thus thrown back into the flue gas and continue to fly.
  • the configuration of the separation system should preferably be such that only a minimum of space is used and that the amount of chimney rain is reduced and minimized as far as possible to an unavoidable level.
  • a precipitator whose effect is based on the impact of the drops - a baffle or a lamella - will also quickly accumulate oily components on the surface under the given ambient conditions, which then prevent the build-up of an approaching drop of absorbing water film. This significantly affects the separation function.
  • the basic principle of the baffle is (as already mentioned) that form water films on the baffles, which ensure that the drops do not sputter on impact and continue to fly as a reduced spray, but that the amount of liquid of the drops is absorbed by the water film and bound - - lent without secondary spray.
  • a lubricated separator can not train this water film, it does not work because of that. So it must be found an alternative solution that makes the water film is no longer necessary. If the spraying drops then spray, this must be done in a preferably pressure-reduced or even unpressurized room so that the secondary drops are not re-entered into the gas flow.
  • baffles or lamellae should preferably be easy to pull and ideally also during operation, so that they can be exchanged and / or cleaned. As a result of this cleaning, the oiling can be reduced and preferably also kept at a minimum value. Therefore, then the for the deposition negative influence of the VER ⁇ lung reduced and ideally to be reduced to a minimum.
  • the replacement of the fins should preferably be done during operation in order to avoid downtime of the diesel engine can.
  • the cleaning of the slats can then take place offline.
  • the separation system is preferably to be designed so that this replacement can be carried out without risk to the personnel during operation. It is also an object of the invention to keep the REA as small as possible. Small means in this case that the height of the entire system is minimized. The height of ships is limited, and the chimney can not protrude arbitrarily high out of the ship. It is therefore necessary to keep the height necessary for the separation system as small as possible, preferably to minimize.
  • a lamella must be washed regularly to remove fine ash or other solids that, on the one hand, clog the separation system over time and, on the other hand, form deposits on the lamellae which progressively worsen deposition.
  • the washing leads in the side effect to a short-term considerable ejection of liquid in the form of chimney rain.
  • the clean gas that is produced after passing through the REA is known to be a saturated gas with a high temperature of, for example, 50 ° C. to 65 ° C.
  • a high temperature for example, 50 ° C. to 65 ° C.
  • condensation takes place on the chimney walls because the chimneys stone wall is usually 20 ° C to 50 ° C colder than the flue gas.
  • the condensate is - if a sufficient amount of which has formed - demolished from the clean gas and ejected in the form of chimney rain from the chimney.
  • These three types of formation lead to sulfuric acid-containing chimney rain, which is correspondingly corrosive.
  • the separation system according to the invention should preferably reduce all three types of origin, minimizing as far as possible.
  • the inventive deposition system at least one longitudinally elongated blade whose longitudinal direction is aligned transversely or obliquely to the flow direction of the flue gas, comprising a chamber with a réellere- ckenden in the longitudinal direction opening, wherein the opening in one of the flow direction is arranged facing side of the blade, at least a portion of the entrained by the gas stream drops and spray drops is passed directly into this chamber.
  • these drops collide against the walls of the chamber, but this does not result in the formation of secondary spray, unlike a blade known in the art, which can be entrained by the gas flow, since no gas flow flows within the chamber.
  • the inventive design of the blade the impact is removed from the gas path to prevent the formation and removal of the secondary spray.
  • a preferred embodiment of the separation system has one or a plurality of modules, each module comprising at least one, preferably a plurality of lamellae.
  • each module or modules it is then particularly preferred for the module or modules to be designed and arranged in such a way that they respectively define an inflow area which faces the flow direction.
  • the gas flow is preferably directed to the inflow surface.
  • the at least one lamella in contrast to the prior art is not installed in a container of REA, through which the flue gas flows before exiting in flue gas ducts or in a chimney, but in the chimney.
  • the overall height of the container is significantly shortened, for example by 1,000 to 2,000 mm, which meets the desire to reduce the space requirements of the REA to minimize possible.
  • the installation in the chimney also makes it possible to replace the slats during operation. Because it is not completely avoidable with a lamella exchange that leaks occur and flue gas can escape. This is a significant problem for personnel, especially when the work has to be done in a closed room where the container is located.
  • the at least one lamella is arranged in the vicinity of the outlet opening of the chimney. This solves the problem of condensate ejection.
  • the condensates formed in the wet chimney are carried with the flue gas to the separator and separated there before the flue gas emerges from the chimney.
  • the cross section of the chimney near the outlet can be made significantly larger than the cross section of the chimney. The flue gas velocity is thereby reduced and there is a lower pressure drop in the separator and the separation efficiency is improved.
  • a lamella is particularly effective in reducing or even avoiding chimney rain, which comprises: a) a surface profile having regions preferably angled in an alternate sense, and b) at least first and second longitudinal profiles in each case a central region and two adjoining edge regions at opposite edges of the middle region, each of which ends in an outer edge, which are preferably angled in accordance with the surface profile, at least the first and the second longitudinal profile each having its middle region on one
  • the area of the surface profile are fixed offset in such a way that the edge regions of a longitudinal profile are spaced at preferably parallel areas of the surface profile with a distance, and at least the outer edge of one of the edge regions of the first longitudinal profile to the outer edge of a Randbe- Rich of the second longitudinal profile has a distance, so that between the areas of the surface profile and the edge regions, a chamber and between the two outer edges of the edge regions, the opening is formed.
  • this chamber separator The special function of this chamber separator is that the drops do not bounce in the flue gas flow against a resistance but rather fly into the chamber and there bounce in the space against the plates. The result of this is that the secondary drops produced by the impact are not thrown back into the flue gas flow, but remain in the chamber and separate there. It lacks the sweeping gas flow, which could cause a transfer of the secondary drops.
  • Oiling leads to the fact that no film of water can form on the surface, which could absorb the bouncing drops. This leads to the significantly increased deposition of secondary drops. In the chamber, this does not matter, because the receiving gas flow is missing.
  • the secondary drops are either carried away by the following drops or they precipitate out by gravity - but usually do not get back into the gas stream.
  • At least two longitudinal profiles are attached to such a lamella on both sides of the surface profile.
  • the separation system can be further improved and the cleaning cycle can be extended by placing a roller separator in the head of the REA tank.
  • this roller separator has the function of reducing the amount of drops in the flue gas and, on the other hand, of intercepting and binding oily components before they reach the actual separator.
  • FIG. 2 is a perspective view of a blade used in this case
  • Fig. 3 used in a separation system according to the invention
  • Lamella again in a perspective view; 4 shows a module comprising a plurality of lamellae of the type shown in FIG. 3;
  • Fig. 5 shows a first embodiment of a separation system according to the invention in a sectional side view
  • FIG. 6 shows a further embodiment of a separation system according to the invention in a FIG. 5 corresponding view.
  • the in Fig. 1, belonging to the prior art separation system comprises a container 7, through which a flue gas stream 9 in the flow direction R, that is passed from bottom to top.
  • the container 7 has a lateral inlet E.
  • the container 7 comprises a sump T, which serves to collect liquid.
  • an outlet U is provided, through which the collected liquid can be discharged and optionally fed to a further use or cleaning.
  • the flue gas flows through a spray assembly 5, with which in the flue gas liquid in the form of a spray for binding S0 2 or S0 3 and washing out of solids is supplied. Drops are formed which have absorbed S0 2 or S0 3 as well as the solids content.
  • a test port 8 is provided which enables the introduction or connection of corresponding measuring devices or measuring probes.
  • droplet separators which consist of a plurality of laterally juxtaposed layers of Abscheiderlamellen, for example - as shown in FIG. 2 shown schematically - consist of curved layers of flat material.
  • FIG. 2 shown schematically - consist of curved layers of flat material.
  • an inventive separation system comprises a lamella 1, which comprises at least one chamber 2 with an opening 2a extending in the longitudinal direction L of the lamella.
  • An embodiment of such a blade is shown in Fig. 3. It comprises a surface profile 14 with regions 15 which are preferably angled in an alternating manner.
  • At least one first and one second longitudinal profile 16, 17 each having a central region 18 and two edge regions 19, 19 'adjoining opposite edges of the central region in an outer edge 20, 20 ⁇ end, which are angled in accordance with the surface profile, each with its central region 18 each attached to a portion 15 of the surface profile 14 offset such that the edge regions 19, 19 ⁇ of a longitudinal profile parallel to extending portions 15 of Surface profiles 14 are spaced at a distance D.
  • At least the outer edge 20 ⁇ of one of the edge regions 19 of the first longitudinal profile 16 has the outer distance 20 of an edge portion 19 of the second longitudinal profile 17 at a distance A, so that between the areas 15 of the surface profile 14 and the two edge regions 19 ⁇ 19, the chamber 2 and between the two outer edges 20 ⁇ 20 of the edge regions 19 ⁇ 19, the opening 2a is formed.
  • On both sides of the surface profile 14th are each two longitudinal profiles 16, 17 attached. It has been shown that a separator with such a lamella substantially reduces the formation of chimney rain. This can be explained by the fact that at least some of the drops do not bounce off outer surfaces and form a secondary spray, but enter the chamber 2 and possibly fail to enter the flue gas stream 9 in a rebound of walls of the chambers forming secondary spray.
  • a plurality of lamellae 1 can be combined to form a module by preferably parallel and further preferably equidistant arrangement, preferably such that the module can be arranged in the separation system such that it forms an inflow surface F, which is transversely or obliquely to Flow direction R runs.
  • the mist eliminator 6 is not disposed within the container 7, but in the chimney S itself and here in the vicinity of its outlet opening 10.
  • the spray assembly 5 is located near the upper end of the container 5.
  • the modules 13 comprising a plurality of lamellae 1 shown in FIG. 4 are arranged flat such that the inflow surface F extends transversely to the flow direction of the flue gas R.
  • a removable receptacle 21 is provided, which is designed such that the modules 13 are exchangeable during operation of the ship's diesel. This interchangeability during operation is particularly possible, since the modules are arranged within the chimney, so that 21 possibly exiting gases during the change process in the area of the exchange pickup directly into the open.
  • the modules 13 are arranged in such a way that - with respect to the flow direction of the flue gas - with a respective adjacent module, the shape of a V or an inverted V
  • the inflow surfaces F of the modules 13 thus run obliquely to the flow direction of the flue gas R.
  • a multi-layer roller separator 22 is arranged in the upper region of the container 7, also referred to as "absorber head". Its function is, on the one hand, to reduce the amount of drops in the flue gas and, on the other hand, to absorb and bind oily components before they reach the modules 13. With the help of the roller separator, the separation efficiency of the separation system can be further improved and the cleaning cycles can be extended.
  • this second embodiment of the separation system 200 essentially corresponds to the first exemplary embodiment, so reference is made to the description thereof.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Treating Waste Gases (AREA)
  • Separating Particles In Gases By Inertia (AREA)
  • Gas Separation By Absorption (AREA)
  • Exhaust Gas After Treatment (AREA)

Abstract

L'invention concerne un système de séparation d'une installation de désulfuration de gaz de combustion d'un navire pour la séparation de gouttes d'un gaz de combustion, qui s'écoule, de préférence avec une composante d'écoulement orientée verticalement vers le haut, dans une direction d'écoulement (R) et qui sort à travers l'ouverture de sortie d'une cheminée, comportant au moins une lamelle (1) allongée dans une direction longitudinale (L), dont la direction longitudinale (L) est orientée de façon transversale ou oblique par rapport à la direction d'écoulement (R). La lamelle (1) comprend au moins une chambre (2) pourvue d'une ouverture (2a) s'étendant dans la direction longitudinale (L), l'ouverture (2a) étant disposée respectivement sur un côté de la lamelle (1) faisant face à la direction d'écoulement (R).
EP18779619.8A 2017-10-10 2018-09-25 Système de séparation d'une installation de désulfuration de gaz de combustion d'un navire Withdrawn EP3694624A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE202017106122.1U DE202017106122U1 (de) 2017-10-10 2017-10-10 Abscheidesystem einer Rauchgasentschwefelungsanlage eines Schiffes
PCT/EP2018/075915 WO2019072543A1 (fr) 2017-10-10 2018-09-25 Système de séparation d'une installation de désulfuration de gaz de combustion d'un navire

Publications (1)

Publication Number Publication Date
EP3694624A1 true EP3694624A1 (fr) 2020-08-19

Family

ID=63713854

Family Applications (1)

Application Number Title Priority Date Filing Date
EP18779619.8A Withdrawn EP3694624A1 (fr) 2017-10-10 2018-09-25 Système de séparation d'une installation de désulfuration de gaz de combustion d'un navire

Country Status (6)

Country Link
EP (1) EP3694624A1 (fr)
JP (1) JP2020536726A (fr)
KR (1) KR20200062195A (fr)
CN (1) CN111246925A (fr)
DE (1) DE202017106122U1 (fr)
WO (1) WO2019072543A1 (fr)

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3405511A (en) * 1966-05-16 1968-10-15 Burgess Manning Co Vane type separator
DE1289030C2 (de) * 1967-11-25 1974-10-31 Steinmueller Gmbh L & C Vorrichtung zur Abscheidung von Fluessigkeiten aus Gas-Fluessigkeits-Gemischen
DE2251173C2 (de) * 1972-10-19 1979-08-30 L. & C. Steinmueller Gmbh, 5270 Gummersbach Abscheidevorrichtung
JPS6012114A (ja) * 1983-06-30 1985-01-22 Isuzu Seisakusho:Kk 排ガス浄化処理装置
FR2598800B1 (fr) * 1986-05-14 1990-10-05 Framatome Sa Separateur de particules liquides a ailettes
DE202010016752U1 (de) * 2010-12-17 2011-03-10 Rea Plastik Tech Gmbh Rollenabscheider als Feinstabscheider zur Vermeidung von Schornsteinregen
NO335786B1 (no) * 2013-02-22 2015-02-16 Marine Global Holding As Marin eksosgassrensing
WO2017151167A1 (fr) * 2016-03-03 2017-09-08 Belco Technologies Corporation Système d'épurateur de gaz d'échappement destiné à de multiples sources
JP6104491B1 (ja) * 2017-01-20 2017-03-29 三菱日立パワーシステムズ株式会社 船舶用脱硫装置および該船舶用脱硫装置を搭載した船舶

Also Published As

Publication number Publication date
CN111246925A (zh) 2020-06-05
JP2020536726A (ja) 2020-12-17
WO2019072543A1 (fr) 2019-04-18
DE202017106122U1 (de) 2019-01-14
KR20200062195A (ko) 2020-06-03

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