JPS63236599A - Biological purifying method of diethanolamine in sewage - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the biological purification of sewage, and more particularly, the present invention relates to a method for purifying jetanolamine in sewage.

[Conventional technology]

The present invention will prove useful in businesses dealing with the purification of natural gas from sulfur components such as hydrogen sulfide, mercaptans, these steps being
A 30% aqueous solution of jetanolamine is used,
This jetanolamine aqueous solution is subjected to chemical desorption for the removal of the sulfide metals and then purified over activated carbon in a specific adsorber, and the purified jetanolamine is subjected to the above production cycle. will be returned to.

Sewage discharged from equipment suitable for the amine purification of natural gas from its sulfur components is characterized by varying concentrations of jetanolamine, with jetanolamine concentrations of 30
Highly concentrated sewage with 00-15000 zy/d1 and jetanolamine 50-100 zg/J
It is divided into two streams: the slightly contaminated sewage containing x';

The first of the two streams cannot currently be purified and continues to pollute the environment by burying it in underground absorption strata.

These methods of removing contamination do not eliminate the risk of contaminants entering surface water or groundwater.

Gas processing plant sewage, which is slightly contaminated with jetanolamine, contains a small amount (
Contains methanol (1-50 mg/da), di- and polyethylene glycols, condensed gas hydrocarbons, mercaptans, surfactants and pyridines.

Such sewage is subjected to treatment in biological purification plants, where it is treated with activated sludge.

Nowadays, industrial purification of sewage utilizes methods of biodegradation of nitrogen-containing compounds with the aid of microorganisms. Thus, for example, aniline and dye industry sewage containing aniline, nitrobenzene, diphenylaniline is treated with microorganisms Bacillus and Pseudomonas.

This microbial mixture is introduced into sewage, the ratio of microbial mixture to sewage being 1:5 to 30. This known method cannot be used for the purification of sewage containing jetanolamine, since the microorganisms used are not able to degrade jetanolamine. Moreover, the known technology requires the use of large amounts of microorganisms and is time consuming (No. 812,763 of the Union of Soviet Socialist Republics).
No. Inventor's Certificate, March 15, 1981 Public 1m, CI.

(See C02F 3/34).

Methods of biological purification by activated sludge of sewage discharged by gas processing plants are known in the prior art;
There, biogenic additives
ditive) consists of jetanolamine.

This activated sludge reduces the salt content of purified sewage,
and degree of purification of sewage
fi-cation) (inventor's certificate of the Union of Soviet Socialist Republics No. 835969, June 1981)
Published on May 7th, C1, C02F 31021).

This method is effective only in the case of sewage slightly contaminated with jetanolamine (not exceeding 1 OOH/J1").

For high concentrations of jetanolamine in the sewage purified by this method, the activated sludge microorganisms do not achieve complete decomposition of the jetanolamine.

That is, the oxidizing ability of microorganisms rapidly decreases, resulting in a decrease in the degree of purification of sewage. On the other hand, 2000 ag/, :Im
``At higher concentrations, the activated sludge dies and the purification process stops.6 [Problems to be Solved by the Invention] The main purpose of the present invention is to eliminate jetanolamine, which is present in high concentrations in sewage. The object of the present invention is to provide a biological purification method for sewage that utilizes microorganisms that decompose sewage.

[Means for solving problems]

This problem is solved by providing a method for biologically removing ethanolamine from sewage, which method involves culturing microorganisms on sewage containing ethanolamine, minerals, and trace elements, and this cultivation step. This is achieved by carrying out up to the point where the sewage is purified from jetanolamine, where, according to the invention, the function of the microorganisms is carried out by the living groups of the microorganisms Pseudomonas and Bacillus (
The microorganisms were selected by natural selection when activated sludge was cultivated on a nutrient medium containing high concentrations of jetanolamine.

According to the invention, the microbial mixture is about 98-99%
In order to obtain a degree of purification of 1:1,000 to 5,000, the ratio of sewage to volume should be 1:1,000 to 5,000.

According to the present invention, in order to maintain a degree of sewage purification of around 98%, this purification operation should be carried out at a pH of 7.2 to 8.8.

[Effect]

Other objects and advantages of the invention will become apparent from the following detailed description of a method for purifying sewage of jetanolamine and from examples of the realization of said method.

The present inventor has been studying the species of the microbial and protozoan communities in activated sludge of a biological purification plant that processes sulfur-containing natural gas. This activated sludge was proven to be enriched with microorganisms capable of oxidizing low concentrations of dissolved organic matter contained in the sewage water specific to a given industry.

For example, jetanolamine is used in Bacillus (Bacillus)
1us) and Pseudomonas
It has been proven that it is oxidized by bacteria of the genus Nas.

This fact served as the basis for the directional selection of a life group consisting of any microorganisms of the above genus capable of oxidizing jetanolamine at concentrations exceeding 100 OH/1 m3. A method for the purification of amine-containing sewage is realized by culturing microorganisms in sewage containing jetanolamine, trace elements and the previously introduced phosphorus sources, such as orthophosphoric acid, at a concentration of more than 1 O00xg/dx. is represented by the living groups of microorganisms, Pseudomonas and Bacillus.

The inventors selected the above microorganisms by natural selection by culturing activated sludge used in biological purification methods of waste left after the treatment of hydrogen sulfide-containing natural gas.

The nutrient medium used for this purpose contained jetanolamine at various concentrations. At the maximum concentration of jetanolamine in the medium, separation of living groups of Pseudomonas and Bacillus microorganisms was performed. Thus, the inventors have obtained a living population of the above-mentioned microorganisms, which are capable of decomposing high concentrations of jetanolamine, and which are capable of decomposing other specific types of sewage discharged by public utilities that process hydrogen sulfide-containing gases. resistant to attack by pollutants.

In order to guarantee a high degree of purification (99%) of sewage containing jetanolamine in an amount of 1000 x g/4 m3 or more, the above microbial life group should be present at a ratio of 1:10 to the volume of sewage.
Advantageously, it is introduced into the sewage to be purified in a ratio of from 0.00 to 5000, and the pH of the sewage is preferably maintained in the range from 7.2 to 8.8.

The separation of the microorganisms, Pseudomonas and Bacillus life groups, should occur simultaneously with the purification of the sewage, so that the selection step has no effect on the duration of the appropriate biological purification.

〔Example〕

Example 1 This biological purification is formed in a facility for amine loading of natural gas from sulfur components in a gas processing plant.
It is intended to decontaminate highly concentrated jetanolamine-containing sewage.

In order to isolate the living groups of microorganisms Pseudomonas and Bacillus applied to jetanolamine, an industrial aerated tank (ae rotank)
Activated sludge collected from the aeration area of xytank))
Culture on nutrient medium containing jetanolamine at various concentrations.

The sewage is neutralized to pH 7.5 with orthophosphoric acid, thus introducing a suitable amount of phosphorus. 1. Next, 500 g of living organisms of microorganisms, Pseudomonas and Bacillus, are added to 5001 m of neutralized sewage. Group to sewage ratio of 1:
1000 is set.

A laboratory biological reaction tank (work area volume = 3, OJx co) is filled with living groups of microorganisms, Pseudomonas and Bacillus, and an adc.
Neutralized sewage containing oxidation of biocenosis (this sewage has a pH of 7.5 and a chemical oxygen demand of 1).
y He nconsumption) 1480zy
/Ji3, biochemical oxygen demand
loxygen de+sand)420zg/J
z3) and with air input,
The oxygen concentration dissolved in this reaction tank is 6mg/l1m
``Let this be the case. Continue this purification process for 10 days.''

The parameters of sewage purification are summarized in the table below.

Example 2 Sewage is stripped of jetanolamine under conditions similar to Example 1. However, the concentration of jetanolamine is set to sewage pH 8.0, chemical oxygen demand 3000xg/e11,
Biochemical oxygen demand site 840H/11m3, 2000
zy/lx.

To the sewage having the above composition, 170 g of living groups of microorganisms, Pseudomonas and Bacillus, are added to set the living group to sewage ratio of 1:3000. This purification step is the same as described in Example 1.

Various parameters of sewage purification are shown in the table below.

Example 3 Purification of jetanolamine in sewage is carried out in the same manner as in Example 1.

However, the concentration of jetanolamine is pH 8.8, chemical oxygen quenching! ! The amount was 450011 F/, /II, and the biochemical oxygen demand ML was 1280 H/, L++3 at 3000 &lF/da3. To the sewage with such a composition, 100 FI of living groups of microorganisms, Pseudomonas and Bacillus were added, and the ratio of living groups to sewage was reduced to 1.
: Set to 5000. This purification method is the same as that outlined in Example 1.

Purification parameters are given in the table below.

(The following is a blank space) [Effects of the Invention] According to the present invention, the purification level (puri) of sewage containing jetanolamine at a concentration of 1000 H/lx3 or more
fication degree) is 98-99%
can be reached.

Representative person

Claims (3)

[Claims] (1) A biological purification method for diethanolamine in sewage containing diethanolamine, a phosphorus source, and trace elements, in which microorganisms are cultured until the sewage is purified from diethanolamine, wherein the microorganism is a microorganism. , a sewage diethanolamine organism, which is represented by the living groups of the genera Pseudomonas and Bacillus, and is selected by natural selection when culturing activated sludge in a nutrient medium containing a high concentration of diethanolamine. Scientific purification method. (2) The living group of the above microorganisms is 1 per volume of the above sewage.
The biological purification method for diethanolamine in sewage according to claim 1, wherein the ratio is from 1000 to 5000. (3) Biological purification of diethanolamine in sewage according to claim 1 or 2, wherein the purification step is carried out at a pH of 7.2 to 8.8. Method.