Patent ID: 11940213
Assignee: WENKER GMBH & CO. KG
Field: Chemical engineering (Chemistry)
Classification: CPC F  Y | IPC F

Claim 8:
9. A process for drying of drying goods in at least one thermodynamically controllable drying plant, wherein the drying goods are conveyed through at least one drying tunnel in a conveying direction and thereby dried, comprising:
exhaust gases containing volatile organic compounds are sucked off through at least one exhaust gas pipe from the at least one drying tunnel;
the exhaust gases are transported by at least one blower controlled by a frequency converter to at least one heat exchanger, whereby an amount of the sucked off exhaust gases is controlled;
the exhaust gases are, at least temporarily, heated to variable exhaust gas temperatures in the at least one heat exchanger by clean gas in at least one clean gas pipe upstream of at least one thermal post-combustion chamber facility;
the exhaust gases are transported through at least one cold bypass circumventing the at least one heat exchanger and connecting the at least one exhaust gas pipe upstream and downstream of the at least one heat exchanger, the at least one cold bypass being regulated by at least one pilot valve controlled by at least one control station, wherein the pilot valve remains temporarily open or closed or remains partially or completely open or closed during a complete drying process, wherein a temperature of exhaust gas is kept constant or is varied;
the exhaust gases are transported through the at least one exhaust gas pipe from the at least one heat exchanger to at least one burner;
the exhaust gases are mixed in varying amounts with fuel which is supplied by at least one fuel pipe;
the exhaust gases are burned in the at least one burner in at least one combustion chamber of at least one thermal post-combustion facility in at least one flame at variable combustion chamber temperatures;
the clean gas having variable temperatures is transported out of the at least one combustion chamber through the at least one clean gas pipe to the at least one heat exchanger, wherein the clean gas variably heats the sucked off exhaust gases at least temporarily;
the clean gas exiting the at least one heat exchanger is transported to at least one heat consumer, wherein a varying amount of heat is taken from the clean gas, which amount is used for varyingly heating of the at least one drying tunnel; and
the clean gas is released into atmosphere as clean gas exhaust, wherein an algorithm of at least one thermodynamic control unit is based on:, Equation I: Control Equation for a measuring station downstream of the heat exchanger:

ĖTNV[W]+ĖAG[W]=ĖWA[W]+ĖRGD[W];, Equation II: Control Equation relative to a vantage point of the at least one thermal post-combustion facility:

ĖTNV[W]=ĖWA[W]+ĖRGD[W]−ĖAG[W];, Equation III: control difference Δ upstream of the control unit:

Δ={ĖWA[W]+ĖRGD[W]−ĖAG[W]}−ĖTNV[W];, with ĖWA [W]+ĖRGD [W]−ĖAG [W]=target value and ĖTNV [W]=actual value, wherein the target value is defined as follows:
(i) ĖWA [W] as a heat reduction of the drying plant to be compensated,
(ii) ĖAG [W] as a recuperation of heat from the drying plant to be compensated/included, and
(iii) ĖRGD [W] as an energy content of the clean gas exhaust;, Regulating Variable: a volume stream {dot over (V)} at normal or standard conditions (temperature=273.15 K, pressure=1013.25 mbar); and, Equation IV: a combustion chamber temperature:

TBK=f({dot over (V)}variabel),, wherein {dot over (V)}variabel=volume stream of the clean gas in the at least one clean gas pipe.