CA1156697A

CA1156697A - Method of pneumatically conveying fine-grain fuel to a gasifier

Info

Publication number: CA1156697A
Application number: CA000360773A
Authority: CA
Inventors: Karl Peter; Heinz J. Filipiak; Wolfgang Grams
Original assignee: SAARBERG DR C OTTO GESELLSCHAFT fur KOHLEDRUCKVERGASUNG MBH
Current assignee: SAARBERG DR C OTTO GESELLSCHAFT fur KOHLEDRUCKVERGASUNG MBH
Priority date: 1979-09-22
Filing date: 1980-09-19
Publication date: 1983-11-08
Also published as: GB2059377B; FR2466044A1; PL226791A1; GB2059377A; BR8006000A; ZA805781B; DE2938369A1; AU6246680A; IN153341B

Abstract

ABSTRACT OF THE DISCLOSURE
A method of operating a device for the pneumatic conveyance of fine-grain fuels to a gasifier, in which the propellent gas and also a pressure maintaining gas (tensioning gas) are introduced into a tank provided with an entry lock, and feed the fuel to the gasifier via conveying pipes which is characterized in that the quantity of fuel supplied to the gasifier is controlled by a device which measures the difference between the pressure in the pressurized tank and the pressure in the gasifier.

Description

2 -A method of ?neu~ tically conveying fine-grain fuel to a ga~ifisr This invention relate~ to a method of operating a device for the pneumatic conveyance of fine-grain fuels to a gasifier, in which the ~ropellent gas and also a pressure maintaining ~ ten~oning ~as~
are introduced into a tank provided with an entry lock, ~nd feed the fuel to the gasifier via conveying pipes.
It ia known to pro~ide pressurized tanks of this kind ~rith no~zle a~semblies, i.e.~ vertically adjustable conduits ectending throu~h the ta~k wall for the conveying gas, an open pipe of the same size being disposed axially above the top end o~ the conduit and Oerving to convey the fuel - a ground and dried coal - to the gasifier. The bottom end of the conduit is adjustablG by up to about 50 ~ for example. The hei~ht of an ~ular gap betwee~ the t~o pipe ends can thus be adjusted and the gap can also be closed~
The object of thi~ invention is to control in the simple~t pos~ible way the qu~nti~y of fuel fed by the pre~Ouri~ed t2~k to the gasifier.
Experiments with pneumatic conveyors of thi~ ki.nd ha~e surprisin~ly sho~m that there is a l;~ear relationship bet.,een the quantity of fine-grain fuel fed to the gasi~ier throu~h the conduit connecting the pr~ssuriæed t~lk and the ~sifier~ ar.d ths di~ference in pressures between the pre~surized t~lk on the one hand and the gasifier on the other.
Accordingly, the invention propoces that the tran~mitter used to control the amount of fuel fed to the gasifier should be a device ,' :

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ch measures the said differenlial precs~eO The control can be effected, for example, by var~Jing the rate of flow Or the press~re maintaining ga~ fed into the pressurized tank. The control can al~o be effected by influencing other operating variable~ on which the amount of fuel fed to the conve~ing conduit is dependentO
The pre~sure-difference meaOuring device is connected to a device adjusted to the set-value of a s~ecific differential pressure equivalent to the required qua~tity of delivered coal. Ii` the actual value devlate~ from the set value~ a control member is actuated by me~ns of which the rate of flow of pre~sure maintaining gas i~ altered.

1 ~5~697 The accompanyin~ dra~"in~ show~ one exemplified embodiment of performance of the new proress in a plant for conveying fine-~rain fuel to a ga~ifier.
A ga~ifier 10 and a ~ressurized tank 11 are 3hown ~urely diagra~matically. Reference 12 denotes the fine-grain coal filling in the pressurized tanlcv Reference 13 denotes the propellent ~as supply pipe, which contains a valve 14 and which is ~ubject to the action of an instrument 26 for controlling the gas throughput. Reference 15 is the conduit for supp].~ing the flow of pressure maintaining gas, and this conduit contains a valve 16. The coal is conveyed from the tank 11 to the gasifier 10 via a conduit 17.
Conduit portion 13 and conveyin~ conduit 17 are connected by a conduit 18 extending through the tanlc 11. In6ide the filling 12, conduit 18 is provided ~.rth a clo6ure device 19 such that ~rhen it ia open the fine-grain fuel passes from the filling 12 into ccnduit 18 and then into the conveying conduit 17.
Reference 20 is a device which on the one hand i~ connected by a conduit 21 to ths ta~ç 11 and on the other hand ~via the ccnduit 22 to the ga3ifier 10. It mea~ure~ the di~ference in the pre~ures in the two device~ This differential pres6ure is an index of the amount of fine-grain material conveyed through the conduit 17.
The am.ount of fuel fed per unit of time to the gasifier 10 determines the differential pres~ure mea~ured in the device 20. To keep the a~ount of fuel con~tant, a specific value mu3t be maintained for the differential ~res~ure between ~he ga~ifier and the pre~surized tank.

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.' ' 1 1 5~69 ' ` ' Thia differential presaure value i~ fed to the set-value tra~3mitter 23. The device~ 20 and 23 act U~G~ the controller 24, I the latter detect~ deviations of the actual value measured by device 20 from the set value, it influences valve 16 via conduit 25, and hence the ~upply of pres~ure maintaining gas, in the direction ~uch that the predetermined value for the differential pre~sure bet~reen the pres~urized tank and the gasifier is re~tored, so that the quantity of fine-grain fuel delivered to the g~sifier via conduit 17 has the predetermined value~
It is clear that thi~ type of control for the operation of the gasifier i~ very simple and requires only simple equipment.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Method for the regulation of the throughput of pneumatically conveyed fine-particled fuel through a transport conductor, which is conducted through a container subjected to the pressure of a pressurizing gas and which joins the container with a gasifier, wherein the transport conductor contains closure means within the container for permitting the fine-particled fuel to pass into the transport conductor when the closure means is open, characterized in that the regula-tion of the amount of fuel led into the gasifier is effected in dependence upon the pressure difference between that in the container and that in the gasifier, which pressure difference is measured by known means and compared with a reference point, and in that the flow of the pressurizing gas led into the container is increased with variations of the pressure difference below the reference point and decreased with variations above the reference point.