CN1445012A - Method for solid-liquid separation of ferment fluid in carnine production - Google Patents

Abstract

A solid-liquid separation process for the biologically fermented inosine liquid includes such steps as acidifying regulating pH value to become neutral with NaOH solution, adding high-basicity aluminium-polychloride while high-speed stirring, adding cationic polyacrylamide, slow stirring for 3-5 min, deposition, getting supernatant, washing deposit 2-3 times with clean water, and filtering the supernatant, washing water and deposit. Its advantages are high removal rate of solid (98%), and high recovery rate of inosine (95% or more).

Description

A kind of solid-liquid separating method that is used for the inosine production fermented liquid

The invention belongs to inosine production fermented liquid coagulation isolation technique

The inosine production fermented liquid is meant the resulting mixed solution that contains multiple inosine substratum such as sugar, nitrogenous source, inorganic salt of inosine biological fermentation process.Because the microorganism growth metabolism is the ten minutes complex process, produce multiple elementary and secondary metabolite, make fermented liquid composition complexity, certainly melt the cell debris and the cell itself of generation as cell, sugar, protein-based colloidalmaterial that microbial metabolism generates, and the remaining nutritive substance that is not absorbed fully and utilize in the substratum, and the product inosine only accounts for a wherein less part.For the extraction and the purifying of follow-up inosine, at first need solid impurities such as colloidal state such as the microorganism cells of various fragmentations in the fermented liquid, sugar, protein and fiber grain thing are separated and remove.Because bio-fermented liquid is a complex system, microorganism cells and tiny, sugared, the protein-based gummous substance of fragment have increased the viscosity of fermented liquid simultaneously, thereby make the removal of solid impurity become difficult.

At present, the fermented liquid solid-liquid separation mainly adopts following several method: supercentrifugal process, and this method facility investment is bigger, and operation and maintenance cost is higher; Ultrafiltration process, this method is simple to operate, and product yield is higher, but ultra-filtration membrane is difficult in maintenance, and life cycle is too short; Coagulation Method (adding aluminum salts such as Tai-Ace S 150 separately), the powerful stirring or the centrifugal solid-liquid separation of carrying out.Because have the different colloidal impurity of a large amount of molecules in the fermented liquid, and the less electric charge of aluminium molecules of salt amount is low, is difficult to complete flocculation sediment, thereby it is low to separate clearance, product yield is not high.Especially at inosine fermentation broth, do not see economical and effective separating and extracting method so far as yet.

The invention provides a kind of cost-effective inosine fermentation broth flocculation separation method, that this method has is easy and simple to handle, less investment, good separating effect and economic dispatch advantage.Adopt present method to handle inosine fermentation broth, the filtrate that obtains clarification, solid impurity content is few, and the loss of product inosine is less, has improved the inosine yield of subsequent extracted, purifying process significantly.

The technology of the present invention key is: 1, at first with alkali lye acidifying fermented liquid pH value is adjusted to 6～8, not-acidified then adjust pH not; 2, add the flocculant of polymeric aluminium chloride of high-basicity, colloidal impurity is taken off rapidly surely; 3, adding small cations polyacrylamide coagulant aids again, to make it to form big floc particle settlement separate rapidly; 4, the sediment water washes repeatedly, and confuses upper clear liquid and separate through the plate-and-frame filter press press filtration together.Concrete operation method is: at first inosine fermentation broth is regulated pH value to 6～8 with NaOH solution, not-acidified uncomfortable, under the quick stirring velocity that per minute 200 changes, add concentration then and be the flocculant of polymeric aluminium chloride of 5% high-basicity, make that colloidal solid takes off surely in the inosine fermentation broth, add 0.2% cationic-type polyacrylamide coagulant aids subsequently, continue to stir 1 minute fast, under the stirring velocity that per minute 50 changes, stirred slowly 3～5 minutes then, form the bulk floc particle, left standstill 10～15 minutes, inclining supernatant liquor, and sediment washs 2～3 times with clear water, and wash water and supernatant liquor mix through the plate-and-frame filter press press filtration.Sediment after will washing at last carries out press filtration through plate-and-frame filter press again to be handled.Then all filtrates are mixed, be used for follow-up inosine product abstraction process, filter cake is disposed direct incineration disposal through dehydration.

Below by example the present invention is done to describe in detail.

Embodiment one

Get inosine fermentation broth 2.95L after the acidifying in coagulator, this fermented liquid pH value 3.5, inosine content is 3.093%, admittedly outstanding thing content 3.734g/L.The NaOH solution of adding 30% is regulated pH to 6～8, under the stirring velocity that per minute 200 changes, add 5% high-basicity flocculant of polymeric aluminium chloride 750ml earlier, adding concentration again after 2～3 minutes is 0.2% cationic-type polyacrylamide coagulant aids 240ml, continue to stir 1 minute, under the speed that per minute 50 changes, stirred slowly 3 minutes then, sedimentation 10 minutes, incline and supernatant liquor, with twice washing of 3L moisture sediment, wash water mixes with supernatant liquor, crosses the plate-and-frame filter press of diatomite precoated layer, sediment is crossed plate-and-frame filter press then, obtain filtrate 6.315L, admittedly filtrate inosine content 1.405% is outstanding thing content 0.0158g/L, conversion inosine yield is 97.2%, admittedly outstanding thing clearance 99.1%.

Embodiment two

Get unacidified inosine fermentation broth 3L in coagulator, the pH value 6.0 of this fermented liquid, inosine content is 3.409%, admittedly outstanding thing content 2.961g/L.Under the stirring velocity that per minute 200 changes, add 5% high-basicity flocculant of polymeric aluminium chloride 750ml earlier, adding concentration again after 2～3 minutes is 0.2% cationic-type polyacrylamide coagulant aids 180ml, continue to stir 1 minute, under the speed that per minute 50 changes, stirred slowly 3 minutes then, sedimentation 10 minutes, inclining supernatant liquor, with twice washing of 3L moisture sediment, wash water mixes with supernatant liquor, cross the plate-and-frame filter press of diatomite precoated layer, sediment is crossed plate-and-frame filter press then, obtains filtrate 6.388L, filtrate inosine content 1.365%, admittedly outstanding thing content 0.0221g/L, the yield of conversion inosine is 95.3%, admittedly outstanding thing clearance 98.4%.

Claims (3)

1, the present invention is a kind of cost-effective inosine bio-fermented liquid solid-liquid separating method, its treatment process is at first acidifying fermentation liquid to be regulated pH value to 6～8 with NaOH solution, not-acidified uncomfortable, and this fermented liquid is pumped into flocculation stir (200 rev/mins) fast in the stirred reactor.

2, described under quick agitation condition as right 1, at first add the flocculant of polymeric aluminium chloride of basicity more than 80% by the flocculation program, and then the adding molecular weight is cationic-type polyacrylamide or the chitin flocculation agent of 800-100 ten thousand, handle hypsokinesis through flocculating settling and go out upper clear liquid, sediment washs with clear water.

3, mix with wash water as right 2 described upper clear liquids, adopt the flame filter press press filtration of diatomite precoated layer to separate, the sediment after the washing separates through the plate-and-frame filter press press filtration again, at last all filtrates is mixed, and is used for follow-up inosine abstraction process.