JPH0248520B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a method for producing organic chemical fertilizer using molasses alcohol fermentation waste liquid as part of the raw material.
The present invention relates to a method for reducing bad odor generated during manufacturing.

[Conventional technology]

The production of organic chemical fertilizers that uses molasses alcohol fermentation waste liquid as a part of the raw material is accompanied by the generation of bad odors during production, and the generation of such bad odors poses a pollution problem.
Fertilizer manufacturers have been conducting various studies on deodorizing measures for many years.

This molasses alcoholic fermentation waste liquid is the residue after adding ammonium bicarbonate etc. to the molasses liquid, fermenting and concentrating it, and separating the crude alcohol.
It falls under the so-called by-product vegetable fertilizer that contains potassium, and because it contains organic nitrogen and potassium,
It is effectively used in the fertilizer industry as an excellent organic raw material.

The production of chemical fertilizers involves setting the three fertilizer components of nitrogen, phosphoric acid, and potassium to an appropriate composition, adding ammonia, sulfuric acid, etc., and performing chemical operations such as granulation, drying, cooling, 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, this molasses alcohol fermentation waste liquid is
At room temperature, the characteristic odor of organic acids is not noticeable, but if stored for a long period of time such as in the summer, it may ferment, react with sulfuric acid during the process of making fertilizer, and be heated with drying gas. As a result, various organic acids, which are malodorous components, are vaporized and released into the atmosphere, which causes malodors.

To deodorize such bad odors, gas washing method, adsorption method,
Combustion methods, oxidation methods, etc. are known, and implementation of these various methods has achieved some degree of effectiveness in deodorizing bad odors.

[Problem that the invention seeks to solve]

Each of the above-mentioned methods for deodorizing bad odors requires large-scale equipment, and the latter two methods in particular have an economical problem due to high processing costs; If this method is used alone, some effects can be seen, but it cannot be said to be perfect yet.

Furthermore, bad odor is said to be a sensory pollution and has a very strong subjective element.In particular, people's sense of smell varies depending on their habituation, fatigue, and personal living environment, so residents of affected areas have expectations regarding the degree of odor. It doesn't matter, it either smells or it doesn't.

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 Stevens' theory are known.

However, aversiveness is the basic measure for expressing the bad odor as damage, and the inventors of this invention believe that it is appropriate to express the odor concentration as a criterion for determining deodorization efficiency, so they decided to use a three-point comparison method. As a result of intensive investigation into the causes of bad odors and their elimination using the odor concentration measured using the odor bag method, we discovered that the cause of bad odors was an organic acid commonly known as humic acid. This invention was completed as a result of research and testing on a method that can reduce the amount using a process that is inexpensive and easy.

The three-point comparison odor bag method described above involves injecting the problematic odor into one of a set of three plastic bags filled with odorless air, and determining whether the odor bag can be distinguished from other odorless bags by a judge. It is a method that dilutes the original odor until it disappears and then calculates the dilution factor (dilution factor), and has recently attracted attention as a method that can complement the blind spots of conventional odor measurement methods that rely only on instrumental measurement methods.

[Means for solving problems]

This invention is a method for reducing the bad odor generated during the production of organic chemical fertilizer by controlling the pH during the production process, and in which waste molasses is added as an organic raw material to fertilizer components containing nitrogen, phosphoric acid, potassium, etc. When producing an organic compound fertilizer by adding alcoholic fermentation waste liquid, the method is characterized in that the pH of the organic compound fertilizer during hydration is adjusted to 5.5 or more and less than 6.5 before the granulation step.

This invention is to control the PH during hydration of organic compound fertilizer to a predetermined range before the granulation step in the production of organic compound fertilizer; good.

However, a more effective control is to perform the necessary PH control on the blackstrap alcoholic fermentation waste liquid.

The odor concentration of this molasses alcohol fermentation waste liquid is
Normally 1000 to 3000 by heating or heating
Depending on the storage conditions, there may be cases of more than 3000, and the odor is quite bad.

In addition, the pH fluctuates in the range of approximately 4.8 to 5.4.

A method for adjusting the pH of such molasses alcohol fermentation waste liquid to 5.5 or more and less than 6.5 is to add an alkaline component as described below.

In this case, the alkaline component can also be mixed in advance into the main component of the chemical fertilizer.

As the alkaline substance added to the molasses alcohol fermentation waste liquid, it is preferable to add caustic soda or caustic potash, but it is also possible to add other alkaline substances such as magnesium hydroxide, calcium hydroxide, calcium oxide, etc. as solid substances. .

However, the addition of calcium compounds and magnesium compounds in the alkaline substances reacts with organic acids to form precipitates, so this treatment may be troublesome, but before the granulation process of chemical fertilizer production, calcium This problem can be solved by adding a magnesium compound or the like.

It goes without saying that the method of the present invention may be used to adjust the pH as described above alone, but it may also be carried out in combination with the gas cleaning method or adsorption method described above.

[Effect]

The odor concentration of molasses alcohol fermentation waste liquid is usually 1000 to 3000 by heating.
Depending on storage conditions, it can reach 3,000 or more, and has a considerable odor.

In addition, the PH fluctuates between 4.8 and 5.4, and the inventors believe that the PH fluctuation is mainly due to the respective amounts of amine compounds and organic acids, and by neutralizing this, the PH value can be adjusted. We investigated how the odor changes when the odor changes.

In other words, various amounts of caustic soda were added depending on the pH of the molasses alcohol fermentation waste liquid, and the odor concentration of the generated foul-smelling gas was measured using the three-point comparative odor bag method. The optimal PH value was investigated in detail.

As a result, when directly neutralizing molasses alcoholic fermentation waste liquid, a high pH value of 6.5 is recommended;
When this value is exceeded, the generation of amine compounds increases the occurrence of bad odors, and at this optimum point, it has become possible to reduce the odor concentration of exhaust gas by more than 50% compared to conventional methods.

Although the reason for this is not clear, it is presumed that the transpiration of organic acids is significantly reduced, resulting in a reduction in offensive odor.

On the other hand, if the pH is 6.5 or higher, the amine compound that makes the salt with the organic acid will evaporate, which is undesirable and may cause bad odor.If the pH is less than 5.5, the effect of reducing the bad odor will be weak. This does not meet the purpose of this invention.

To measure the PH of solid substances such as chemical fertilizers, accurately place 5 g of the sample in a 500 ml volumetric flask, and add approximately 50 ml of water.
Add 400ml and shake at 30-40 rpm for 1 minute.
After shaking for 30 minutes, 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."

Example 1 Organic chemical synthesis using 340 parts of ammonium sulfate (ammonium sulfate), 40 parts of ammonium phosphate (ammonium phosphate), 370 parts of lime superphosphate, 134 parts of potassium chloride, 68 parts of dried bacterial fertilizer, and 100 parts of molasses alcoholic fermentation waste liquid. Manufactured fertilizer.

PH of the molasses alcohol fermentation waste liquid used for this
was 5.3, and the odor concentration was 2550.

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 molasses alcohol fermentation waste liquid before treatment was 2550, and the odor concentration of exhaust gas was 170.
After treatment, the odor concentration of molasses alcohol waste liquid is 1180,
The odor concentration of exhaust gas was 80, the odor around the factory disappeared, and the discomfort caused by organic acids disappeared.

In addition, the product organic chemical fertilizer obtained in this way has its PH
has increased from 4.2 to 5.4, which can provide favorable results for users who dislike soil acidification due to fertilizers.

To measure the pH of solid substances such as chemical fertilizers, accurately collect 5 g of a sample into a 500 ml volumetric flask, add approximately 400 ml of water, and shake for 30 minutes with a shaker at 30 to 40 revolutions per minute. , water was added up to the marked line and the liquid was immediately filtered through dry filter paper.

Example 2 An organic chemical fertilizer was produced using 430 parts of ammonium sulfate, 150 parts of ammonium phosphorus, 185 parts of potassium chloride, 150 parts of dried bacterial fertilizer, 10 parts of steamed bone meal, and 140 parts of molasses alcohol fermentation waste liquid.

At this time, the pH of the molasses alcohol fermentation waste liquid was 5.2.
The odor concentration of waste liquid was 3740, and the odor concentration of exhaust gas was 120.

10 parts of 11% caustic soda was added to this to adjust the pH to 6.0.

As a result, the odor concentration of molasses alcohol fermentation waste liquid after adding caustic soda was 1740, and the odor concentration of exhaust gas was
50, and the pH of the product also increased from 5.4 to 6.5, which is favorable in terms of fertilizer application.

In addition, records are compiled based on the reports of dozens of odor monitors in the vicinity of this factory, categorized by major odor sources.
In the year leading up to April 2017, there were 12 reports of fertilizer odor, of which 10 were reported before the implementation of the odor reduction method of this invention, but after implementation, the number dropped sharply to 2. .

〔Effect of the invention〕

As described above, according to the present invention, the pH during hydration of an organic compound fertilizer is controlled within a predetermined range before the granulation step in the production of an organic compound fertilizer using waste molasses alcohol fermentation liquid as an organic raw material. This makes it possible to reduce bad odors easily and economically, and the present invention is effective and valuable as a technology related to pollution prevention.

In addition, according to this invention, the organic chemical fertilizer as a product obtained increases its PH and shifts in the direction of lowering the degree of acidity, but this is due to the fact that 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.

Claims (1)

[Claims] 1 Fertilizer ingredients including nitrogen, phosphoric acid, potassium, etc.
A method for reducing bad odor, which comprises adjusting the PH of the organic compound fertilizer during hydration to 5.5 or more and less than 6.5 before the granulation step, when producing an organic compound fertilizer by adding molasses alcohol fermentation waste liquid as an organic raw material. .