the jet pump to be used for the method of the invention and to be included into the apparatus of the invention is of a very specific type as for instance detailed in ep 1 549 856 b1 and / or wo2006 / 010949 a1 . schematic cross - sections of such jet pumps are shown in and described in connection with fig5 and 6 . fig3 is a schematic diagram of a method and apparatus for an - aerobic digestion of waste water . the mechanical disruption of a sludge forms in the bottom of the digester is made be means of a steam jet pump as shown in fig5 and / or 6 . waste water is provided to screen means 201 . the liquid is fed to aerobic digestion means having as output purified water and sludge . the primary sludge of the screen means 201 and the sludge of the aerobic digester means 202 are fed to an an - aerobic digester means 203 . some sludge output of the an - aerobic digester means 203 is fed into the jet pump 1 , 101 . the disintegrated and / or liquefied sludge is recirculated to the inlet of the an - aerobic digesting means 203 . the remainder output of the an - aerobic digester means will be pressed and dried in the usual manner . the provision of the steam jet pump 1 , 101 instead of a homogenizer as known from the prior art mentioned above has the advantage that the wear and the costs are dramatically reduced . in accordance with an alternative the jet pump 1 , 101 could also be provided in addition or alternatively before the inlet of the an - aerobic digester means 203 such that all sludge to be fed into the an - aerobic digester means has to pass the steam jet pump 1 , 101 . alternatively or in addition a steam jet pump 1 , 101 as shown in and described in connection with fig5 or fig6 can be provided before the aerobic digester means 202 and / or the screen means 201 such that all material to be fed therein has to pass the steam jet pump 1 , 101 . the jet pump 1 , 101 can also potentially be used for treating or processing the aerobic sludge before it is entering the an - aerobic digester means . in accordance with the invention the jet pump 1 , 101 may be used for recirculation the sludge around the aerobic digester means and / or the an - aerobic digester means . according to the invention the jet pump 1 , 101 can also be used in combination with mechanical homogenisation , wherein the jet pump 1 , 101 is to be placed before the homogeniser in order to protect the homogeniser getting damages by the sludge containing sand and grit . according to the invention the primary sludge can be treated only . it is clear that the sludge may be treated in addition thereafter by a jet pump 1 , 101 . fig4 is a schematic diagram of a method and apparatus for an - aerobic digestion of waste water in accordance with another embodiment of the invention . same components as shown in fig3 have same reference numerals . in the following only the differences to the embodiment of fig3 will be described and reference is made to the description of the embodiment of fig3 . the output of the an - aerobic digester means 203 is not fed to the steam jet pump , but some of the sludge output of the aerobic digester 202 is fed into the steam jet pump 1 , 101 . the ph of the sludge may be increased before the treatment with the steam jet pump , for instance by adding naoh . the disintegrated and / or liquefied sludge is then fed to the an - aerobic digester means 203 . the steam jet pump 1 , 101 , as shown in and described in connection with fig5 and 6 , is connected such that liquefying of the cellulosic material takes place before fermenting the cellulosic material . fig5 shows a schematic cross - section of such a jet pump . the jet pump 1 comprises a tube 2 with a tube inlet 3 and a tube outlet 4 . in the wall of tube 2 there is provided an annular ring chamber 6 pipe 5 is connected to . the annular ring chamber 6 is connected to the inner space of tube 2 by nozzle 7 . in operation steam is pressed with a high pressure into pipe 5 and distributed in the annular ring chamber 6 . from the annular ring chamber 6 the steam is guided through nozzle 7 into tube 2 , thereby sucking liquid containing organic material into tube 2 . the organic and / or cellulosic material will be sucked into the tube due to the condensation of the steam into the liquid . there is a reduction in volume as the steam condenses creating a pressure drop in the tube that sucks the material into the tube . the area in the tube adjacent to the exit of nozzle 7 is functioning as a mixing chamber 8 . in operation high pressure steam is directed into pipe 5 , whereby liquid is sucked into the hollow tube 2 via tube inlet 3 , typically with a velocity of 8 to 10 m / s . in the mixing chamber 8 the liquid is mixed with the steam thereby creating a supersonic shockwave 9 because of the condensation of the steam and the high momentum of the steam exiting nozzle 7 . at the exit of nozzle 7 there are supersonic velocities of a mix of steam and water droplets of about 800 m / s . at the tube outlet 8 , the velocity will drop again to velocities of about 8 to 10 m / s . it is clear that the mixing chamber 8 and the supersonic shockwave 9 as shown in fig5 and 6 are only indications where the mixing takes place and shockwave occurs in the tube . it is not necessary that there are any means inserted into the tube in order to provide the mixing of the liquid with the steam and the generation of the supersonic shockwave . these effects are occurring because of the provision of the annular ring chamber 6 and the nozzle 7 directing steam into the liquid sucked into the tube . the high velocities of the water droplets containing the organic material cause a physical disintegration and / or liquefication of the organic material . any sludge agglomerates are physically mascerated to increase the efficiency of the an - aerobic digestion process of the invention by making the smaller agglomerates more accessible to the bacteria . as a result in the method and apparatus of the invention there is less digester sludge to be disposed of . in accordance with the invention nozzle 7 can be an annular ring or a series of pipes distributed along the extension of the annular ring chamber and / or the circumference of the tube . according to an embodiment of the invention having a nozzle comprising pipes , the pipes may be oriented in angle in order to create a vortex in the tube . fig6 shows another embodiment of a jet pump 101 mainly corresponding to the jet pump 1 shown in fig5 . similar parts have been designated with reference numerals increased by 100 . in the following the additional components and / or features are described . for the corresponding features and components reference is made to the description of jet pump 1 as shown in fig5 . the form of annular ring chamber 106 and nozzle 106 has been optimized in order to create a supersonic shock zone 109 . there are annular ring chambers 110 , 112 with pipes and / or nozzles 111 , 113 through which additives or additions can be supplied into tube 102 . the annular ring chambers 110 , 112 have respective connections ( not shown ) for supplying the materials to be added , such as acids and / or enzymes to be used for the hydrolyse of complex polysaccharides . fig7 to 10 are further embodiments of the invention mainly corresponding to the embodiments as shown in and described in connection with fig3 and 4 . the same reference numerals are used to designate similar or identical components . in the following only the differences are described . in the embodiments of fig7 to 10 there are filter means 204 provided to filter the material exiting the an - aerobic digester means 203 . according to the embodiment of fig7 there are two jet pumps 1 , 101 provided as shown in and described in connection with fig5 and 6 . jet pump a is provided between the outlet of the aerobic digester means 202 where the sludge is exiting and the inlet an - aerobic digester means 203 . the primary sludge from the screen filter means 201 is fed directly into the inlet of the an - aerobic digester means 203 bypassing jet pump a . alternatively the primary sludge of the screen filter means may be directed through jet pump a or a further jet pump ( not shown ). jet pump b is arranged and connected in order to treat and recirculate the an - aerobic sludge exiting the an - aerobic digester means to the inlet of the an - aerobic digester means . fig8 is an embodiment of the invention where jet pump b of the embodiment of fig7 is omitted . fig9 is an embodiment of the invention where jet pump a of the embodiment of fig7 is omitted . fig1 is an embodiment where a jet pump 1 , 101 as shown in and described in connection with fig5 or 6 is provided between the outlet of screen filter means 201 and the inlet of the an - aerobic digester means 203 in order to treat the primary sludge of the screen filter means 201 before entering the an - aerobic digester means . in accordance with the invention embodiments comprising the use of a jet pump in any of the positions as shown in fig7 to 10 are envisaged , either alone or in any possible combination . for instance the provision of three jet pumps at the position as shown in fig8 , as shown in fig9 and as shown in fig1 is possible . in accordance with the invention , in addition and preferably before or better instead of the homogenizer as used in the prior art methods and apparatuses , a jet pump creating a supersonic shock wave to disintegrate and / or liquefy the organic material and / or sludge is used . accordingly a jet pump as described above and as known in the prior art for other purposes and being incorporated by reference is to be used instead of the homogenizer . in other applications the jet pump can be used in the process before the homogenizer . a large proportion of the world biofuel is currently produced from primary materials such as sugar and corn . however , the use of primary food products is inflating the price of food . for this reason , attention is being placed on the economic production of biofuel from secondary plant materials such as grass , sugar beet waste and corn stalks . the waste material must be reduced in size and preferably completely mascerated in order to solubilise the constituent cellulose . once solubilised , the cellulose must be hydrolysed to convert it to carbohydrates that can then be fermented using yeast or bacteria to convert the carbohydrate to ethanol or butanol . the dilute alcohol stream that is produced is then evaporated and then distilled before final drying using a molecular sieve . the use of the steam jet pump which is schematically shown for instance in fig5 or 6 offers a low cost means of rapidly solubilising the cellulose following mechanical disintegration using for example a chopping device . the steam jet pump can also contribute to hydrolysis of the cellulose through the heating effect and by addition of acid prior to entering the pump . an overview of known methods for producing biofuel is disclosed at the home page of the u . s . department of energy , energy efficiency and renewable energy , section biomass program : information resources , which web site address is http :// www1 . eere . energy . gov / biomass / abcs_biofuels . html . the whole disclosure thereof is hereby incorporated by reference . firstly complex polysaccharides are to be converted into simple sugars by hydrolysis . acids and enzymes are used to catalyse the hydrolysis . secondly sugars are converted to ethanol by fermentation caused by yeast or bacteria which fed on the sugars . thereby ethanol and carbon oxide is produced out of the sugar . according to the method and apparatus of the present invention the biomass containing polysaccharide is treated with a jet pump creating a supersonic shock wave . thereby the biomass is liquefied and the polysaccharide may be at least partly hydrolysed . accordingly the invention also relates to a method and an apparatus for microbiologic fermentation of cellulosic material , wherein a jet pump for liquefying pre - cut or pulverised cellulosic material is used .