JPS6284767A - Deodorizing liquid - Google Patents

Abstract

(57) [Abstract] 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 the invention of a deodorizing liquid for the purpose of more effectively and economically deodorizing so-called bad odors in the living environment.

[Conventional technology]

The main odors in the living environment that occur in daily life are the odors of rotting animals and plants, such as toilet odors, rotting garbage odors, odors from poultry and pig farms, and odors from fish and meat processing plants.
Its components are mainly ammonia, hydrogen sulfide, mercaptan,
It is a complex odor that is a mixture of several types of malodorous components, including amines. It can be said that ammonia and hydrogen sulfide account for the majority of the malodorous components. These bad odors in the living environment are inevitably increasing with the increase in the consumption lifestyle of the people, and effective countermeasures against them are now desperately needed as a field of environmental pollution.

By the way, it has been conventionally believed that an aqueous solution of glyoxal is effective as a deodorizing agent for this bad odor in the living environment. This is because an aqueous solution of glyoxal directly reacts with malodorous components and converts them into other substances, and also has little negative impact on microorganisms that decompose waste and remove bacteria. Examples of inventions for turning glyoxal into a gel include JP-A-49-1333'9, JP-A-49-99146, and JP-A-50-29507, and inventions for turning glyoxal into a solid powder include, for example, JP-A-49-1333'9. 35542, etc., but as for aqueous solutions, for example, glyoxal and pH 5
As a deodorizing agent characterized by containing a buffer solution of pH 5 to 9, Japanese Patent Publication No. 48-3383 proposed glyoxal perpetuate (using a buffer) adjusted to pH 5 to 9 in the toilet tank, septic tank, or in the wastewater of the septic tank. Japanese Patent Publication No. 53-43575 was published as a method for deodorizing human waste and its processed materials, which is characterized by the addition of human waste (excluding regulated products).

(Problems to be Solved by the Invention) However, the above-mentioned known examples regarding glyoxal aqueous solutions had various drawbacks.

Since glyoxal is a highly reactive dialdehyde, it is particularly reactive with ammonia and its derivatives, and the pH of the glyoxal aqueous solution does not have a direct significant effect on the reaction with ammonia, but it does not have a significant effect on the reaction with hydrogen sulfide. pl+ of glyoxal aqueous solution has a large influence, and pi
(When is about 1 to 3, the reaction rate is extremely slow. Therefore,
As in the above-mentioned known example, p)I5 is added to glyoxal aqueous solution.
It has been considered to use a Mjj solution of ~9 or to adjust the pH value alone to 5 to 9, but the reaction rate against hydrogen sulfide is still insufficient by adjusting the pH value alone, and the economic efficiency is still insufficient. There were also some problems.

That is, in the deodorizing reaction of glyoxal, a particularly large amount of glyoxal is required relative to ammonia and hydrogen sulfide, and the weight ratio is 1 part ammonia to 2 parts glyoxal, and 1 part hydrogen sulfide to 1.5 parts glyoxal.
It becomes 4.

Therefore, while maintaining the characteristics of the conventional glyoxal aqueous solution, we conducted a separate chemical reaction with hydrogen sulfide to remove ammonia and hydrogen sulfide, which are the main components of bad odors in the living environment, as efficiently and economically as possible. The development of a deodorizing liquid that does not have any effect on microorganisms that decompose filth has been awaited.

[Means and effects for solving the problems] The present invention is novel in order to achieve the above object.

That is, the pH of the glyoxal aqueous solution is set to 3.5 to 4.
Limited to 5. If this pH value is 5 or more, the reaction rate against hydrogen sulfide becomes faster by itself, but as shown in later experimental examples, this is still not sufficient. An industrially produced glyoxal aqueous solution with a pH value of 3 or less has the disadvantage that the reaction against hydrogen sulfide is considerably slow and that it kills microorganisms. Therefore, the pH value is limited as mentioned above, so as not to affect microorganisms.
It was decided that the reaction to hydrogen sulfide would be solved by a separate method. As already explained, the reaction to ammonia has little relation to the p)l value of the glyoxal aqueous solution, but it can be said that the reactivity is relatively good at pH 3.5 to 4.5 since it is in a weakly acidic range.

Based on the original effectiveness of glyoxal aqueous solution as a deodorizing liquid, we decided to use the reaction of ferrous sulfate to treat hydrogen sulfide and separate and remove it as iron sulfide. The sulfuric acid produced in this reaction process reacts with ammonium ions in the odor-containing liquid to remove ammonia odor and further synergistically enhance the deodorizing effect and speed. In addition, ferrous sulfate is added to the glyoxal aqueous solution with water so that its content is 3% or less. Add as l. And the content is 0.3 to 0.8
% is generally preferred, but the content may be further increased in places where particularly large amounts of hydrogen sulfide and ammonia are generated, such as physical waste dumps.

Further, the concentration of the ferrous sulfate aqueous solution is preferably about 1 a% or less.

Note that if the content exceeds 3%, precipitates are likely to be formed, the reaction will be poor, and it will not be effective.

〔Example〕

Example 1 At a frozen ground treatment plant in Kyoto Prefecture, the results of an experiment on the deodorizing effect of thickened sludge in the treatment plant are as follows.

(A) When glyoxal aqueous solution (concentration 10%) adjusted to pl+6 is used (B) When 20.6 ferrous sulfate is added to the glyoxal aqueous solution (concentration 10%) adjusted to pH 4.5 of the present invention Example 2 The results of an experiment conducted at a dust treatment plant in Higashiosaka City regarding the deodorizing effect of concentrated sludge in the dust treatment plant are as follows.

(A) When a glyoxal aqueous solution (concentration 10%) adjusted to pH 6 is used (B) Ferrous sulfate of 0.4! From the above example, the removal rate for hydrogen sulfide is significantly improved and the removal rate for ammonia is almost complete, as well as the consumption rate is reduced by half, compared to conventional known examples. It has been proven that only one is required.

〔Effect of the invention〕

As described above, the present invention not only has (1) almost complete deodorizing effect on ammonia and hydrogen sulfide, but also (2)
It is economical in that the amount consumed to achieve this effect is less than half that of conventional deodorants. It also serves as an indicator of the effectiveness of the hour wheel, and has great practical effects in that it is not necessary to conduct a point-by-point analysis, and the timing of replacement due to the passage of the period of use can be easily determined by visual inspection.

Claims (1)

[Claims] 1. A deodorizing liquid characterized by adding an aqueous solution of ferrous sulfate to a glyoxal aqueous solution adjusted to pH 3.5 to 4.5 to reduce the ferrous sulfate content to 3% or less.