摘要:
The ability of a waste gas cleaning spray drying absorber to tolerate substantial variations in the amount of waste gas to be cleaned is enhanced by a system which provides for introduction of any amount of waste gas that would overload the gas disperser(s) of the spray drying absorber, into said absorber via auxiliary apertures in the walls thereof thereby bypassing the gas disperser(s).A plant for cleaning fluctuating amounts of waste gas comprises a control system based on measurement of gas flow to the gas disperser(s).
摘要:
A gas distributor and heating device for a spray dryer which includes a feed liquid atomizer in a drying chamber, a gas distributor for supplying a uniform flow of gas, a guide duct for conveying the flow of gas from the gas distributor and to an outlet providing a flow of processing or drying gas to contact liquid droplets dispersed by the atomizer. A gas heater is located in the device between the gas distributor and the guide duct outlet to heat the gas just prior to its introduction into the spray chamber. This provides a high temperature drying gas close to the atomizer and avoids problems encountered in attempting to transfer a gas that has been heated at a location remote from the spray chamber. A guide duct in the form of an annular guide duct provides an annular flow of heated gas concentric with the atomizer. A gas burner extends circumferentially around the interior of the guide duct and is disposed to emit the gases of combustion in the direction of the outlet. The guide duct may also include a plate shielding a portion of the gas flow from direct contact with the burner and the gases of combustion to provide an insulating flow of gas between the annular duct and the combustion zone.
摘要:
Hot waste gas is desulfurized in a spray drying-absorption process performed in an absorption chamber wherein a fluidized layer of partially reacted absorbent is maintained in the bottom area. Improved conditions are obtained for the reaction between absorbent and sulfur oxides in the waste gas, whereby the use of inexpensive absorbents of relatively low reactivity, such as limestone, comes into consideration.
摘要:
A processing gas is supplied to the atomizing zone around an atomizing device arranged centrally in an atomizing chamber through a conical guide duct communicating with a horizontal spiral duct through an annular mouth. A gas distribution incorporating a simple and accurate adjustment of the deflection of the gas stream from the spiral duct into the conical guide duct is obtained by means of two separate sets of stationary guide vanes arranged relatively close to and overlying each other in the mouth, one of said sets being constructed to deflect the gas stream stronger than the other set to a direction with a considerably smaller tangential velocity component, a damper being arranged along the mouth to be adjustable in the height direction for controlling the ratio of the portions of the gas stream in the spiral duct conducted into each of the two vane sets.
摘要:
A method and apparatus for drying disintegrated fiber mass or paper pulp comprising substantially free single fibers and wads or lumps of fibers. The disintegrated fiber mass is exposed to hot drying air or gas at a temperature of at least 180.degree. C. Free fibers are separated from the fiber mass during or after the drying process in order to avoid or compensate for excessive heating and drying of these free fibers. This facilitates a later grinding process in which the dried fiber mass is ground after addition of water.
摘要:
A rotor for spreading a particulate product into a fluid bed comprises a shaft or core member defining an axis of rotation. Peripherally spaced spreading members extend outwardly from the shaft or core member, and the radial extensions of peripherally adjacent spreading members are different viewed in transverse sections of the rotor. The spreading members may form vanes or wings extending axially along the shaft or core member, and the spacing of the free edge of each vane or wing from the axis of rotation may vary along the length of the rotor.
摘要:
A processing gas is supplied to the atomizing zone around an atomizing device arranged centrally in an atomizing chamber through a conical guide duct communicating with a horizontal spiral supply duct through an annular mouth. A uniform gas distribution with respect to flow direction and velocity is obtained by means of guide vanes arranged with a small angular spacing in the mouth and comprising two succeeding vane sets, in which the vanes of one set are shaped to deflect the tangential gas stream in the spiral duct to a flow direction, for which the radial velocity component considerably exceeds the tangential component, whereas each vane of the other set positioned at the opening of the mouth towards the conical guide duct projects into the space between neighboring vanes of the first set and extends substantially parallel to tangential planes to said vanes at their internal edges.