Pure water and concentrates are recovered from dilute fermentation substrates or wash waters, e.g. in winemaking cellars, beverage and glucose production and breweries

摘要

Pure water and concentrates are recovered by extraction and concentration of dilute substrates or wash waters stabilized with a recycled volatile bactericidal additive. Pure water and concentrates are obtained from dilute substrates or wash waters mainly containing sugars and volatile compounds from fermentation, by: (a) storage of the dilute substrates or wash waters stabilized by addition of a volatile bactericidal product; (b) column extraction of the volatile compounds to produce a concentrated bactericide solution for recycling and for production of concentrated organic distillates; (c) evaporative concentration of the treated substrates with elimination of volatile organic acids from the vapor by scrubbing in a column supplied with an alkaline solution; (d) combination of the concentrates; and (e) storage and stabilization of the purified water for further use. An Independent claim is also included for an installation for carrying out the above process, comprising: (i) a stirred storage tank (SSD) for the dilute substrate (SD) mixed with absorption liquor (BV) and a volatile bactericide (aBV); (ii) a heat exchanger (R) for preheating the dilute substrate; (iii) extraction and concentration columns (CS, CC) fitted with condensers (C1, C2); (iv) a non-condensed product transfer system and a volatile bactericide absorption column (CA) for producing the absorption liquor (BV); (v) an energy efficient evaporator (EV) which concentrates the substrate transferred from the extraction column (CS) and which consists of an exchange surface, a cyclone separator, a column for vapor scrubbing with alkaline solution (CLA), a thermocompressor (TC) fed with pressurized steam and a mechanical steam compressor (C); (vi) a stirred storage tank for the treated water (ET) which can be supplied with volatile bactericide after stabilization; (vii) a stirred storage tank for the concentrated and reconstituted wort (SMR); and (viii) a stirred storage tank for the concentrated distillates (SDC). Preferred Features: The volatile bactericide is a solution of SO2 or formaldehyde, recycled with greater than 98% efficiency. The purified water (ET) comprises the condensed vapors from the evaporator (EV) and is reused for washing operations. The extraction column (CS) is heated solely by steam (VbP) from the evaporator (EV), the steam optionally being compressed by mechanical compression. The evaporator (EV) is a cascade type evaporator in which liquid is recirculated and distributed by a conical spray nozzle and which has an exterior/interior tube temperature difference of 3-8 deg C. The scrubber column has an upper stage fed with condensate and a lower stage fed with recirculated alkaline solution.