according to fig1 there is illustrated a reactor vessel of the type disclosed in the parent patent application ser . no . 44347 / 75 ( ser . no . 625 , 311 ) comprising a reactor tube 112 , a driven feed device for driving waste products through the reactor tube between entrance and delivery ends thereof , a heating device around said reactor tube for heating the waste products in the vessel , an airtight charging hopper including air exclusion locks , an airtight delivery chamber , and a blower ( not shown ) the suction end of which is connected to the delivery end of the reactor tube . the apparatus is arranged on a platform in such a way that the reactor tube 112 lies substantially horizontally . on the entrance side , which is on the left in the drawing , the apparatus is pivotably mounted on a bearing block 101 , in a pivot bearing 102 . at the delivery end , which is represented in the right hand part of the drawing , a pair of lifting links 104 are mounted below the apparatus which is to be supported , one end of one link being connected to the platform and one end of the other link being connected to the delivery end of the apparatus . the lifting links 104 are operable via a threaded spindle 103 which operates on their adjacent ends and which is threadedly mounted at 105 in a pivotably mounted nut . if the threaded spindle 103 is rotated via the hand wheel 106 in such a way that the end of the threaded spindle moves to the right , the lifting links are thereby extended in such a way that the delivery end of the apparatus is raised . however , other lifting devices can be used depending upon the weight of the apparatus . in fig2 the apparatus is illustrated in the position in which the threaded spindle 103 is moved so far to the right that the lifting links 104 are in line and have thus lifted the apparatus to the maximum extent . as is evident from fig2 the reactor tube 112 ascends relatively steeply from the entrance end to the delivery end . a fluid level shown by a dot - dash line in fig2 can thereby be produced . the gaseous substances can collect in the space in the reactor tube which is represented by shading in fig2 . by tilting the tube 112 in this way , the reaction time of waste products in the tube 112 can be controlled as no fluid substances can emerge from the delivery end of the reactor device if the incline of the reactor tube 112 is suitably adjusted . the incline of the reactor tube 112 can easily be optimally adjusted during operation in dependence upon the products being treated and in dependence upon the progress of the pyrolisis . fig3 shows a perspective view of a hollow driving shaft 114 , on which radially projecting paddle blades 120 are mounted at a predetermined angle of attack . the paddle blades 120 , together with the hollow driving shaft 114 , form the feed device for the products which are to be treated in the reactor tube 112 . fig4 illustrates in detail in a cross - section through the hollow shaft 114 , the means by which the paddle blades 120 are fastened to the hollow driving shaft 114 . a threaded pin 121 which is fixed radially to the paddle blade 120 serves to fasten the paddle blade 120 , which pin passes through corresponding openings in the hollow driving shaft 114 and is fastened on the opposite side by a nut 122 . in order to vary the angle of attack of one paddle blade 120 , it is sufficient to slacken the nut 122 , so that the paddle blade 120 can then be rotated in the desired manner and the nut 122 can finally be tightened again . with the aid of the arrangement represented in fig4 the angle of attack of the individual paddle blades can be adjusted in a simple manner to the desired amount , depending upon the progress of the method or upon the product which is being treated . with the aid of the arrangement represented in fig4 by varying the angle of attack of the blades , the feed velocity can be optimally adjusted in each of the preheating / gasification / delivery zones . a paddle blade 120 which extends over a particularly large arc is represented in fig5 . the arc occupied by the paddle blade 120 in fig5 is almost 180 °. the fastening of the paddle blade represented in fig5 corresponds to the arrangement which is represented in fig4 . paddle blades extending over particularly large arcs are especially suitable for use in conjunction with a heated hollow shaft 114 . if a hot fluid is conducted through the hollow shaft 114 , the paddle blades 120 are also heated with the hollow shaft 114 , and by this means good heat transference to the product being treated in the reactor tube can be obtained . in this case a transverse tube 123 is inserted gastightly into the hollow shaft 114 ( fig6 ). here , the gastightly inserted transverse tube 123 serves the purpose , on the one hand , of accepting the threaded pin 121 of the paddle blade 120 , and on the other hand , of preventing an escape of the hot fluid which is conducted through the hollow shaft 114 via the connection of the paddle blade 120 to the hollow shaft 114 . the shaft of the threaded pin 121 is a sliding fit in the transverse tube 123 in order to promote good heat transference . the transverse tube 123 is advantageously welded to the hollow shaft 114 , in order to produce a durable gastight connection . there has thus been described apparatus for carrying out pyrolysis of waste products of the type mentioned at the outset , which may contain fluid products or deposits and which can treat them for a predetermined time in the reactor and with a consistently high degree of efficiency .