DE1658043C3 - Process for the purification of protein-containing waste water using the nitrogen-containing impurities present therein - Google Patents

Description

3 4

Results, for example after drying, as animal The result of a typical experiment is

feed. be used. BSIi ₅ before treatment 3160 mg / 1

The lignosulfonic acids are relatively high-molecular-weight _{ßSß after fermentation for 24 hours}

Substances which, however, have a somewhat vamerende molecular _{mjt Toru} | _{opsis ulilis 1810 mg /} ,

have weights. In each molecule, however, only 5 _{3S3 according to Niede} ' _{rsc} l} , _a g _{with ver} .

an acidic function on. As a result, the molecular _{edeher Lj} g _nin5u , _fonsäure .. 2000 mg /!

weight a certain importance for the precipitation _{ßSß after precipitation} | _{ag with ver} .

process. In general, lignosulphonic _{acids are less of a ligninäu} | _{fonic acid}

with an average molecular weight of about 500 _{and subsequent fermentation}

preferred. If the molecular weight was substantially io _{with ToruIopsjs utiljs} .

is less, the particles of the formed _{fend H hours} .. ₂ 4O mg / 1

Complex too small and light, so that failure

Causes difficulties. Is the molecular weight The synergistic effect is likely to be explained

on the other hand, much greater, the consumption is too borrowed in such a way that the precipitation of the protein substances and

large, precisely because only one acid function for every 15 polypeptides gives the microorganisms better nutritional

Lignin sulfonic acid molecule. Provided for different conditions. It is known that many

However, borrowed proteins can contain slightly different microorganisms in nutrient sub5i; a? .Ti

Molecular weights of lignosulfonic acid optimally large amounts of complex-bound nitrogen or

be, and an expedient form of too much nitrogen will not thrive at all.

The method according to the invention is characterized by 20 If the precipitation with a subsequent biological

from the fact that the precipitation is combined in two or more steps gical purification,

with sulfonic acids of different molecular weights achieved results. Case in point

tes is made. This will do another is:

Advantage achieved. It has been shown that proteins with _{ßSß before treatment} 3000 _mg / |

relatively high molecular weight best 25 _{ßSBs needle} loosing biological

with relatively high molecular weight Ligninsulfonsäuitn from purification 1800 mg / 1

are precipitated, while low molecular weight proteins BDB ₅ after precipitating with refined

preferably with low molecular weight ligninsulphonic ligninsulphonic acid 1600 mg / 1

acids precipitated from earth. By failing in two of the _{ßSßs according to Fäl] mj [LigninsuI} .

several. Stages one therefore achieves a coarse frac- 3 = fonsäure and subsequent ones

tiomerung of the proteins, wa ·. for their use of ten hour biological

Meaning can be. Cleaning ^ T 100 mg / 1

Several microorganisms are known to carry out the fermentation according to the invention. dal ¹ , one is particularly suitable for the above-mentioned Torulopsis utiiis. 35 Treatment in which the BOD ₅ amount upon precipitation

In general, the lignosulfonic acids with refined ligninsulfonic acid are increased from 3000 to 1600 mg / l

or their salts in refined form of a sulphite deposit, there was an increase when using sulphite liquor

which, as is known, would receive 4200 mg / l in addition to lignosulfonic acids.

contains significant amounts of pentoses and hexoses. In further experiments a solution of 50 g

prefer. 40 blood albumin treated in 5 l of water. The BSB ₅ / N ₂ -

It can happen that the ratio of proteins and the like was very unfavorable here, namely 6: 1. the

freed wastewater is so nutritionally poor that it was purposely achieved data:

it is moderate to slightly increase the nutritional content. BOD- before treatment 6000 mg / 1

E. On the other hand, it can be appropriate. Ammonia to _BOD " _{after 2} 4 hours biological
Use an easily accessible nitrogen source 45 'Reinipnnc with active
for a microorganism and its growth forms sludge 4600 mg / l
not hindered if it is used in suitable quantities _{after the} precipitation. Ammonia e.gncl also da / u, ^J _edc , _ter , jgninsulphonic acid. . 900 mg / 1
Give the liquid a suitable pH value to ν.ι _{BSß n; I never} go wrong with
- often about 6 or 6 to 7. On the other hand, one can use 50 ^J cdclter ligninsulphonic acid and
optionally sugary waste materials, such as. B. subsequent 24 hour
Molasses, to promote the growth of the micro- biological cleaning ~. ... 50 mg / 1.
Clog the organism. If ammonia is added,

and the waste water with sulfuric acid or: j,.! zsäiire The process of the invention is described below

was made acidic, ammonium sulfate or 55 is explained using an exemplary embodiment:
-chloride form, which are also easily exploitable

StickstörTquellen are the growth of the micro example
Promote organisms. Before biological cleaning

If necessary, the storage controller can be disconnected. During an experiment on a technical scale

will. 60 were 6 m ^{3 of} wastewater from a potato starch factory

As mentioned, the handling according to the invention leads to treatment. The wastewater contained 3 g of nitrogenous

lung, d. H. first precipitation with lignin sulfonic acids and compounds and 3 g reducible sugar per liter

then fermentation and biological purification to one and was totaled with 2700 g lignin sulfonic acid

synergistic effect, as from the following sodium salt, ie 450 g each in ³ and one as large

emerges. 65 amount of sulfuric acid that a pH of about 4.5

The cleaning effectuiii! on the wastewater is reached here, treated, [Lie stickMofThaltigfn Ver

through the BOD

consumed oxygen per liter of wastewater) (Dotailanalysc was not carried out) from

teins and their decomposition products, d. H. Polypeptides with larger or smaller chain lengths and amino acids. With the addition of the ligninsulphonic acid salt the proteins precipitated almost instantaneously and formed a slurry of them. The slurry was filtered through a sand filter in which the sand was covered with silica. A minor one Amount of the clear filtrate was washed back through the filter, with an essentially Concentrated slurry was produced, from which the precipitated proteins were obtained in a known manner and could be used afterwards.

The clear filtrate still contains 1.7 g nitrogen-containing compound per liter, namely dissolved: peptides and Amino acids. The sugar content was not affected by the treatment.

The pH of the clear filtrate was 4.5 and was increased to 6 ^{by adding 180 g of liquid ammonia per m 3.} In addition, 0.5 kg of beet sugar molasses with a sugar content of about 50% and a culture of the fermentation sponge Torulopsis utilis were added ^{per m 3 of filtrate.} It wur'e a submere fermentation in the liquid at a temperature of 30 ⁰ C for 18 hours under air flow of 3 m ³ of air per hour, corresponding to about 1/2 ³ m air per m ^{3 of} liquid per hour performed. After fermentation was complete, 4.8 m ^{3 of} the liquid were removed. The suspended particles, ie practically exclusively microorganisms, were removed from this. The isolation was carried out by means of centrifuges. In the case of larger systems, however, previous filtration should often be useful. During centrifugation, 8 g of compressed yeast per liter of liquid were obtained.

The remaining 1.2 m ³ were used as inoculating liquid for a new fermentation, which was otherwise carried out in the same way and with similar results.

The fermentation, as described, is most expediently submerged in suitable basins or tanks and made during ventilation. It is also possible to ferment as surface fermentation in open boxes to be carried out in a manner known per se.

The table below shows the reduction in the BOD ₅ value in the treated wastewater, measured on samples before precipitation with sodium lignin sulfonic acid, immediately after precipitation and after fermentation during the periods indicated in the table.

ao giving new number of hours.

Before failing 4720

After failing 2810

Fermentation after 1 hour 2140

Fermentation after 3 hours 1430

Fermentation after b hours 780

Fermentation after 9 hours 570

Fermentation after 12 hours 430

Fermentation after 18 hours 98

Claims (5)

Extent to CO. and possibly N? can be transformed, so that organically bound nitrogen is even returned to the patent claims: inorganic form. It is also known to cause wastewater to precipitate 1. Process for purifying protein-containing 5 proteins and similar substances contained therein, Wastewater using the polypeptides present in it to be cleaned with lignin sulfonic acid, nitrogenous impurities, thereby reducing the biological oxygen consumption characterized in that one first pacifies the waste water to a certain extent but not, Polypeptides and similar nitrogenous genes can be reduced, and nitrogenous ones can be used Substances in the sewage by means of ligninsulphon- io substances of the sewage to a certain extent as acids or their salts completely or partially. falls, then separates the precipitated substances, it is also known to sugar sorts in wastewater remaining wastewater to fermentation means in advance with different microorganisms a suitable organism and / or a biological ferment. But even this cannot be satisfactory subject to logical purification. 15 Reduction of the biological oxygen consumption 2. The method according to claim 1, thereby marked can be achieved. draws that the precipitation can be divided into two or a special difficulty both in the bio- several stages with lignin sulfonic acids or logical purification of protein-containing wastewater their salts with different molecular as well as in the utilization of sugar sorts in weight carries out. 20 wastewater lies in the fact that the amount of N-containing 3. The method according to claim 1 or 2, characterized in that compounds compared to the amount of charcoal are often widely hydrated as ligninsulphonic acid in the wastewater to be treated here Sulphite filing used. above the optimum of the individual organisms in the 4. The method according to claim 1 or 2, characterized by a biological filter. This means that the Orgage indicates that one refined to precipitate does not grow as well as it does with one Ligninsulphonic acids or salts thereof reduce the relative amount of N-containing compounds turns. would do. Either the system must immediately 5. The method according to claim 1, characterized by being large, or the wastewater is draws that one of the precipitated pro-inadequately cleaned, with that of the cleaning product If waste water is released ammonia or water diverted away from the plant or fermentation plant continues optionally sugary material, e.g. B. molasses, a much too high biological oxygen consumption at dt ·: fermentation either in one gift or has. added in portions and the fermented wastewater It has now surprisingly been shown that subjected to biological cleaning after avoiding the disadvantages described and If necessary, the fermentation pathogen is separated off beforehand for a reduction in the biological acidity has. Substance consumption of the wastewater at a very low price can achieve. The invention therefore relates to a method for the purification of protein-containing wastewater under 40 Exploitation of the nitrogenous Impurities, which is characterized by The aim of the invention is that the proteins, polypeptides and the like are first used drive a purification of wastewater, with low nitrogenous substances in wastewater means Content of suspended and dissolved material, lignosulfonic acid or its salts in whole or in part this material precipitating proteins and polypeptides 45, then separating the precipitated substances and includes. As examples of such wastewater, there can be used the remaining wastewater by fermentation from dairies, butchers, potato mills, a suitable organism and / o'.hr an organic Subjects fishmeal factories, canning factories and other logical purification. Factories for proteinaceous foods and fodder- When the proper process occurs substances are mentioned. 50 synergistic effect, d. i.e. that the reduction The organic substances contained in the wastewater will increase the biological oxygen consumption punches usually have a certain value than the sum or the product of the reduction means if you z. B. for lining materials, each of the two steps are processed individually, be able. The use of this value reduces the precipitation of proteins with lignin sulfonic acid Wastewater treatment expenses. 35 or its salts takes place practically at an acidic pH value, It is known to purify wastewater by biological rhyme- preferably at pH 4 to 5 and particularly useful- to be cleaned with suitable biological filters. moderate at pH 4.5. In practice, the failure occurs This is generally a very good downgrade, therefore normal with the free lignosulfonic acids, too Setting of the biological oxygen consumption when added in the form of salts thereof cleaned wastewater achieved. The procedure has to be 60. The pH value is regulated by however, the disadvantage that biological filters are both acid, preferably strong mineral Acid requires high investment costs as well as operating costs. In general, sulfuric acid or salt and that the substances retained in the filter used acid. The choice will be mainly can not or almost not be exploited. You judge neutrally by the price. One becomes practical can optionally be more modest than 65 a th ligninsulphonic acids, for example stoeotriometric Diingerstoffe are exploited, but otherwise add quantities of the mineral acid. The nicer- vcrlorcn, as it is mainly a complex of proteins from the product included on the filter active organisms consumed and in significant and lignosulfonic acids and can with very good