Method for producing PHA by continuous treatment of molasses alcohol wastewater via mixed halophilic bacteria

Abstract

The invention relates to a method for producing PHA by continuous treatment of molasses alcohol wastewater via mixed halophilic bacteria and belongs to the technical field of production of PHA. The method comprises the following steps of carrying out activation culture on mixed halophilic sludge to obtain halophilic activated sludge, carrying out enrichment culture on the molasses alcohol wastewater inside an SBR reactor by virtue of mixed halophilic bacteria colony, carrying out continuous PHA production on molasses wastewater inside a continuous flow reactor and recovering PHA in the discharged residual sludge. The PHA is synthesized by virtue of the mixed bacteria colony instead of a pure bacteria colony, strict sterilization procedures is not required, the process is simplified and the cost is saved; the continuous flow process is simple, compared with the fermentation process, the repeated replacement of the fermentation broth is not required, the repeated inoculation of bacterial sludge is not required, the continuous water inlet and continuous water outlet are achieved, respective process parameters tend to a constant value and is simply implemented, the automatic control is facilitated, the method is easily operated in engineering, the yield of PHA is high, the continuous production of PHA is achieved and the resource utilization of residual sludge is also achieved.

Description

technical field [0001] The invention belongs to the technical field of PHA production, and relates to a technical method for synthesizing polyhydroxyalkanoate (PHA) by treating molasses alcohol waste water in a continuous plug-flow reactor by using halophilic mixed flora. The invention is especially suitable for resource recovery in the pretreatment of molasses alcohol wastewater, and has multiple advantages of waste utilization, resource recovery and reduction of PHA industrial production costs. Background technique [0002] At present, worldwide, the industrial production of PHA generally adopts the method of biofermentation with pure bacteria and single substrate. For example, Metabolix Corporation of the United States has created a genetically recombined Escherichia coli K12 strain, which uses glucose as a substrate for fermentation, and can obtain 90% cell dry weight PHA product production in 24 hours. The German Biomer company uses Alcaligenes latus strains to ferment...

AI Technical Summary

Problems solved by technology

However, the batch fermentation process has obvious defects: ① During the fermentation process, acid-base solution must be continuously added to the fermenter to control the pH, and special dosing equipment must be configured; the fermenter must be cleaned and disinfected after each cycle; It is necessary to replace the fermentation broth, etc., which consumes a lot of manpower, material resources, and power; ②The production cycle is short, because the bacteria have a certain growth law during batch fermentation, they all go through the lag phase, logarithmic growth phase, stable phase and The decline period, and each batch of fermentation must go through the stages of strain expansion fermentation, equipment washing, sterilization, etc.; ③The production efficiency is low, because the entire fermentation cycle includes the time of discharging, washing tanks, feeding, and sterilizing, it is actually effective The fermentation time is short and the fermentation efficiency is very low