JPH0459099A - Method for deodorizing sludge - Google Patents

Abstract

PURPOSE:To rapidly and continuously deodorize and decompose sludge and to prevent discharge of offensive odor into the environment by impregnating a powdery carrier with liquid deodorization substance excellent in deodorization effect to obtain a deodorant and utilizing this deodorant. CONSTITUTION:A powdery carrier is impregnated with a liquid deodorization substance to obtain a deodorant. This deodorant is added to sludge and thereafter sludge is dehydrated. The utilized liquid deodorization substance is not especially limited but stabilized chlorine dioxide and wood vinegar, etc., are desirably utilized. As the utilized powdery carrier, known every material (e.g. powdery calcium silicate, fine powdery silica, activated alumina, talc, diatomaceous earth, charcoal and clay) may be utilized. The loadings of the deodorant depend on the kind thereof and the composition of sludge but are regulated to about 5-3000ppm as the amount of the deodorization substance in the carrier for sludge. Further as a dehydration method of sludge, known every method is utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for safely, rapidly and effectively deodorizing and decomposing sludge.

[Prior Art] One of the problems in treating sludge is that of bad odor. As a countermeasure against this problem, a proposal has been made to perform a deodorizing treatment as a pretreatment for the aggregation step (for example, Japanese Patent Laid-Open No. 164343/1983).

However, this method requires complicated processing steps.

■Hydrogen peroxide, chlorine, etc. are sometimes used as processing agents, but there is a risk of secondary pollution.

■Some liquid deodorizing substances have excellent deodorizing ability, such as stabilized chlorine dioxide and wood vinegar.If the liquid state of the liquid is added to wastewater, too much deodorizing substance will remain in the sludge after coagulation treatment. , it is difficult to obtain sufficient effects for deodorizing sludge. Furthermore, even if liquid deodorizing substances are sprayed on the sludge after flocculation treatment, the effect is only on a part of the surface layer;
Since the process is complicated, it is not suitable for practical use.

■Also, there has been a proposal to add a powdered fungicide in the form of a suspension (Japanese Unexamined Patent Publication No. 1-224098).
Basically, it only has the effect of suppressing bad odors that newly occur due to the action of putrefactive bacteria, and has a weak deodorizing effect on already generated malodorous substances.11) Use powder that is insoluble or poorly soluble in water. Therefore, the disinfectant only acts on the contact area between the powder and sludge.
There were problems such as the time required for the effect to be achieved.

[Problems to be Solved by the Invention] The objects of the present invention are: (1) to be able to quickly and effectively deodorize and decompose sludge without complicating the conventional sludge treatment process, and (2) to avoid the generation of secondary pollution. The purpose of this invention is to provide a method for deodorizing sludge.

[Means for Solving the Problems 1] That is, the present invention is a method for deodorizing a dehydrated cake by adding a deodorizing agent to sludge and then dehydrating it. This relates to a method for deodorizing sludge, characterized in that it is added as a sludge.

[Function] In the sludge deodorizing method of the present invention, by using a powder carrier impregnated with a liquid deodorizing substance, the deodorizing substance is quickly and continuously released from the carrier as it is added to the sludge, and the entire sludge is Because it acts on the skin, it is possible to obtain a rapid and continuous deodorizing effect.

The liquid deodorizing substance used in the method of the present invention is not particularly limited, but it is preferable to use stabilized chlorine dioxide or wood vinegar. These substances not only have a deodorizing or deodorizing effect, but also have sterilizing ability, so they are extremely effective in deodorizing sludge, deodorizing and decomposing existing malodorous substances, and preventing the generation of new malodorous substances through the action of putrefactive bacteria. .

As the powder carrier used in the present invention, any known carrier may be used, such as calcium silicate powder, finely divided silica, activated alumina, talc, diatomaceous earth, charcoal, clay, etc. Further, the liquid deodorizing substance impregnated with the sludge may be in the form of granules or pellets to some extent as long as it is dispersed after the sludge is added.

Depending on the composition of the sludge to be treated, it is also effective to use a combination of deodorizing agents in which a powdered carrier is impregnated with a plurality of deodorizing substances. The amount of deodorizer added depends on the type of deodorizer and the composition of the sludge, but the amount of deodorization in the carrier for the sludge! The amount of F31J is about 5 to 3000 ppm, preferably about 10 to 1.000 ppm.

Note that any known method can be used to dewater the sludge. In addition, if the present invention is not used during the aggregation treatment process,
The carrier is effective because it forms flocs together with the solid content in the sludge due to the action of the flocculant, and the gradually released deodorizing substance continuously acts on the sludge solid content to deodorize and decompose it.

[Examples] Example 1 A deodorizer was prepared by using calcium silicate powder as a carrier and impregnating it with a stabilized chlorine dioxide solution (concentration 50.00 ppm) at a weight ratio of 11.

Next, the deodorizing agent and a polymer flocculant were added to the sludge water to flocculate the solid content, and after dehydration treatment, changes in the odor of the sludge solid content over time were measured.

■The amount of deodorizer added is 1,000 as the amount of stabilized chlorine dioxide.
1) l] Ill and 500 ppm, and for comparison, odor was also measured in the case where no deodorizing agent was added.

(2) Clifflock PA374 manufactured by Kurita Industries, Ltd. was used as a polymer flocculant.

(2) Odor measurement was carried out using a Votaful type odor sensor XP-329 manufactured by Shin-Cosmos Electric Co., Ltd.

■Measurement results are displayed using the following formula.

■Measurement results elapsed time Opening 278 261 250
288 Deodorizer 100pp+n addition 255
224 162 138 Deodorizer 500ppm
Addition 233 206 149 124
[Effects of the Invention] In the present invention, by using a deodorizing agent in which a powder carrier is impregnated with a liquid deodorizing substance having an excellent deodorizing effect, the deodorizing substance in the carrier is gradually released and acts continuously. The sludge is quickly and continuously deodorized and decomposed during the dewatering process and subsequent processes, and does not emit any bad odor into the environment. In addition, there is little transfer of deodorizing substances into the desorbed liquid during the dehydration process, so it can be used in licks, sewage, human waste treatment facilities, etc. without adversely affecting the biological tank in the aeration tank. .

Claims (1)

[Claims] A method for deodorizing sludge, in which a deodorizing agent is added to the sludge, followed by dehydration treatment to deodorize a dehydrated cake, the method comprising adding a powdered carrier impregnated with a liquid deodorizing substance as the deodorizing agent.