JPS6236094A - Bad smell reducing method - 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] [Field of Industrial Application] The present invention relates to a method for reducing bad odors generated during the production of organic chemical fertilizers. The purpose is to reduce the odor concentration generated by controlling the PH1i of the by-product vegetable fertilizer itself or organic compound fertilizer when using available vegetable by-products, so-called by-product vegetable fertilizers. It is something to do.

[Conventional technology]

The production of organic chemical fertilizers is generally accompanied by the generation of foul odors, and the generation of such foul odors has become a pollution problem, and companies that generate such odors have been conducting various studies for many years on measures to eliminate this odor.

By-product vegetable fertilizers, which are generally the source of bad odors in organic chemical fertilizers, are
It is mainly a by-product in the food industry or fermentation industry, and the material is derived from vegetable raw materials.
Known examples of these include soy sauce lees fertilizer, tobacco waste fertilizer, amino acid by-product fertilizer, dried bacterial cell fertilizer, and fermentation by-product fertilizer, among which a representative example is molasses alcohol fermentation waste liquid.

The residue after adding ammonium bicarbonate, etc. to the molasses liquid, fermenting and concentrating it, and separating the crude oil alcohol is the molasses alcohol fermentation waste liquid, which is a so-called by-product vegetable fertilizer containing organic nitrogen and potassium.

This fertilizer contains organic nitrogen and potassium,
It is effectively used in the fertilizer industry as an excellent organic raw material.

Therefore, in the production of chemical fertilizers, the three fertilizer raw materials (nitrogen, phosphoric acid, and processing) are set to an appropriate composition, ammonia, sulfuric acid, etc. are added to this, and chemical operations are applied to granulate, dry, cool, and It is produced by sieving, etc., and in this granulation process, the above-mentioned molasses alcohol fermentation waste liquid is added to produce an organic chemical fertilizer.

However, although this molasses alcoholic fermentation waste liquid does not have much of the odor characteristic of organic acids at room temperature, it may ferment if stored for a long period of time, such as during the summer.
When it is reacted with sulfuric acid during the fertilizer process and heated with drying gas, various organic acids, which are bad-smelling components, are vaporized and released into the atmosphere, which causes bad odors.

Gas washing methods, adsorption methods, combustion methods, oxidation methods, and the like are well known methods for deodorizing such bad odors, and these methods have achieved certain effects when practiced.

[Problems to be Solved by the Invention] Each of the above-mentioned methods for deodorizing bad odors requires large-scale equipment, and the latter two methods in particular have high processing costs. There is a problem in terms of economics, and although the former can be seen to be somewhat effective if treated with only this product, it cannot be said to be perfect yet.

Furthermore, bad odor is a sensory pollution and has a strong subjective element.
Humans' sense of smell differs slightly depending on habituation, fatigue, and individual living environment.

Therefore, the expectations of residents in the affected areas are not whether there is a bad odor, but whether there is a bad odor or not.

Therefore, even if bad odor is removed to a large extent, it does not seem to have been reduced or alleviated to the human senses. .

Regarding this, the Weber-Fechner law and Steepens' theory are known.

However, the aversiveness indication is the basic measure for expressing the bad odor as damage, and the inventors of this invention believe that it is appropriate to indicate the odor concentration as a criterion for determining deodorization efficiency, and compared the three points. As a result of intensive investigation into the causes of malodors and their elimination using the odor concentration measured using the odor bombardment method, we learned that the cause of malodors is an organic acid commonly known as humic acid.

Subsequently, the present invention was completed as a result of research and testing on a method that can reduce this humic acid malodor in an economical and process-wise inexpensive and easy method.

Note that the three-point comparison odor detection method described above uses three
This method involves injecting the problematic Haraoku into one of the plastic bags in the side, diluting the original odor until the judge can no longer distinguish it from other odorless bags, and calculating the dilution factor. This method has attracted attention in recent years as a method that can complement the blind spots of conventional odor measurement methods, which are limited to instrumental measurement methods.

[Solve the problem. means for

This invention is a method for reducing the bad odor generated during the production of organic chemical fertilizers by controlling the pH during the production process. In producing an organic compound fertilizer by adding fertilizer, the pH of the organic compound fertilizer during hydration is adjusted to 4.5 or more and less than 6.5 before the granulation step.

The following describes in detail the removal of bad odors during the production of organic chemical fertilizers using molasses alcohol fermentation waste liquid, which emits extremely unpleasant bad odors, as a by-product vegetable fertilizer element.

This invention is to control the pH during hydration of an organic compound fertilizer to a predetermined range before the granulation step during production of the organic compound fertilizer, but the control is not performed at any step before the granulation step. Good too.

However, a more effective control is to perform the required pH control on the waste liquid of molasses alcohol fermentation.

The odor concentration of this molasses alcohol fermentation waste liquid is usually 1,000 to 3,000 when heated, and depending on the storage conditions, it can exceed 3,000 in some cases, and it has a considerable odor. .

In addition, compared to the old P, it fluctuates in the range of approximately 4.8 to 5.4.

The pH of the molasses alcohol fermentation waste liquid is 5.5 or higher 6
．． A simple and economical method for adjusting the molecular weight to less than 5 is to add an alkaline component as described below. In this case, the alkaline component can be mixed in advance into the main component of the chemical fertilizer.

As the alkaline substance to be added to the molasses alcohol fermentation waste liquid, it is preferable to add -acid group-alkali soluble caustic soda or caustic potash.

It is also possible to add other alkaline substances, such as magnesium hydroxide, calcium hydroxide, calcium oxide, etc., as a solid substance.

However, the addition of calcium compounds and magnesium compounds among the alkaline substances may react with organic acids to form precipitates, and this treatment may be troublesome.

This problem can be solved by adding calcium, magnesium compounds, etc. before the granulation process of chemical fertilizer production.

Of course, the method of the present invention may be used to adjust the pH described above alone, but it may also be carried out in combination with the gas cleaning method or adsorption method described above.

[For production]

As mentioned above, the odor concentration of molasses alcoholic fermentation waste liquid can be reduced by warming or heating, usually from 1°000 to 3,000°C.
000, and depending on storage conditions, it can reach 3,000 or more, and has a considerable odor.

In addition, the pH fluctuates from 4.8 to 5.4, and the inventors believe that this change in PR is mainly due to the respective amounts of amine compounds and organic acids, and by neutralizing this, the pH changes.
We investigated how the odor changes when the value is changed.

That is, various amounts of caustic soda corresponding to the pH of the molasses alcohol fermentation waste liquid were added, and the odor concentration of the generated foul-smelling gas was measured using a three-point comparative odor detection method.
The optimum pH value when the odor concentration is the lowest was investigated in detail.

As a result, when directly neutralizing molasses alcoholic fermentation waste liquid, it is best to set the pH to a maximum of 6.5; if this value is exceeded, the generation of amine compounds will increase the generation of bad odors, and the odor of exhaust gas will increase. At this optimum point, the concentration can be reduced by more than 50% compared to the conventional method.

By adjusting the pH of the molasses alcohol fermentation waste liquid to a range of 5.5 or more and less than 6.5, the occurrence of bad odors was reduced, but this is because the transpiration of organic acids is significantly reduced. It is assumed that.

On the other hand, when the pH is 6.5 or more, the amine compound forming the salt with the organic acid evaporates, which is thought to be the cause of the bad odor.

Also, if the pH is less than 5.5, the odor reduction effect is weak.
This does not meet the purpose of this invention.

In addition, when measuring the PH of solid substances such as chemical fertilizers, 5 g of sample is heated at 500 m j! Accurately put it in a volumetric flask and make 40
After adding 0Ill and shaking for 80 minutes using a shaker that rotates 30 to 40 times per minute, water was added up to the marked line and immediately filtered through dry filter paper, and the pH of the liquid was measured.

〔Example〕

Hereinafter, this invention will be described in more detail with reference to Examples. Note that "parts" in the examples are "parts by weight."

Implementation ■ 340 parts of ammonium sulfate (ammonium sulfate), 40 parts of ammonium phosphate (ammonium phosphate), 370 parts of lime superphosphate, chloride treatment 1
An organic chemical fertilizer was produced using 34 parts of the dried bacterial fertilizer, 68 parts of the dried bacterial fertilizer, and 100 parts of the by-product vegetable fertilizer (molasses alcohol fermentation waste liquid).

The pH of the molasses alcohol fermentation waste liquid used for this was 5.
3. The odor concentration was 2.550.

8 parts of 12.5% caustic soda was added to this molasses alcohol waste liquid, the pH was adjusted to 6.5, and the operation was carried out as described above.

As a result, the odor concentration of the molasses alcohol waste liquid before treatment was
, 550 and the odor concentration of the exhaust gas became 170. After the treatment, the odor concentration of the waste molasses alcohol waste liquid became 1.1800 and the odor concentration of the exhaust gas became 80. The odor around the factory also disappeared and the unpleasant feeling caused by the organic acid disappeared.

In addition, the product organic chemical fertilizer thus obtained has a pH of 4.2.
This has increased from 5.4 to 5.4, which can provide favorable results for users who dislike soil acidification due to fertilizers.

In addition, when measuring Pl+ in solid substances such as chemical fertilizers, 5g of sample is used.
Accurately put the solution into a 50On+42 volumetric flask, add Honsuri 40Oralt, shake it for 30 minutes with a shaker that rotates 30 to 40 times per minute, add water up to the marked line, and immediately filter the liquid with dry filter paper. The pH of the sample was measured.

Organic chemical fertilizer is manufactured using 430 parts of ammonium sulfate, 150 parts of ammonium phosphorus, 185 parts of chloride processing, 150 parts of dried bacterial fertilizer, 10 parts of steamed bone meal, and 140 parts of by-product vegetable fertilizer (molasses alcohol fermentation waste liquid). did.

At this time, the pH of the molasses alcohol fermentation waste liquid was 5.2, the odor concentration of the waste liquid was 3,740, and the odor concentration of the exhaust gas was 120.

To this was added 10 parts of 11% caustic soda and the pH was adjusted to 6.0. As a result, the odor concentration of the molasses alcohol fermentation waste liquid after addition of caustic soda was halved to L740 and exhaust gas odor concentration was 50, and the product pH increased from 5.4 to 6.5, which is favorable in terms of fertilizer application. .

In addition, we have compiled records of major odor sources based on reports from dozens of odor monitors in the vicinity of this factory. There were 12 cases where odor was reported, of which 10 were reported before the implementation of the odor reduction method of this invention.
After implementation, the number of cases decreased sharply to two.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to control the circle 1 at the time of hydration of the organic compound fertilizer within a predetermined range before the granulation process in the production of the organic compound fertilizer, and in particular, to control the circle 1 during hydration of the organic compound fertilizer, which contains an organic acid, etc. By adding an alkaline substance to by-product organic fertilizer substances such as molasses alcohol fermentation waste liquid and controlling the pH within a predetermined range, it is possible to easily and economically reduce bad odors, and this technology has been developed as a technology related to pollution prevention. It is an effective and valuable invention.

Further, according to the present invention, the pH of the organic compound fertilizer obtained as a product increases and the degree of acidity decreases, but this is because the acidification of the soil is prevented when applying the fertilizer. The method of the present invention has great utility value in this respect as well.

Patent applicant Toa Kasei Co., Ltd. Procedure Neho Seisho (Method) % formula % 1. Indication of the case 1985 Patent Application No. 85693 2. Name of the invention Offensive odor reduction method 3. Person making the amendment Case and Relationship between Patent applicant August 26, 1988 (shipping date) 6. Column 7 of "Title of the invention" of the specification subject to amendment, Contents of the amendment (1) As the title of the invention on page 1 of the specification, " The phrase ``Offensive odor reduction method (pollution prevention related technology)'' will be corrected to ``Offensive odor reduction method.''

Claims (1)

[Claims] When producing organic compound fertilizer by adding by-product vegetable fertilizer as an organic raw material to nitrogen, phosphoric acid, potassium fertilizer, etc., P during hydration of the organic compound fertilizer is determined before the granulation process.
A method for reducing bad odor, comprising adjusting H to 4.5 or more and less than 6.5.