JPS58131121A - Deodorizing method - Google Patents

Abstract

PURPOSE:To obtain sufficient deodorizing effect as a whole, by deodorizing a gas to be treated containing malodorous components by matured compost and activated carbon or hypochlorite soda and matured compost in two stags. CONSTITUTION:A gas 1 to be treated is introduced into a humidifier 3 through a blower 2 to be conditioned so as to impart predetermined water content to matured compost in a deodorizing tank 4 in the next stage and the conditioned gas 1 to be treated is introduced into a deodorizing tank 3. Most of ammonia, hydrogen sulfide and mercaptan and a part of methyl sulfide and methyl disulfide in the gas 1 to be treated are removed by the aged compost. In the next step, the partially treated gas 1 is introduced into an activated carbon tank 5 to remove residual malodorous components. In other method, a gas 11 to be treated is introduced into an oxidative washing tower 13 by a blower 12 to be subjected to deodorizing treatment by scattering a sodium hypochlorite solution from the top of the tower 13 through a pump 14, and the partially treated gas is subsequently passed through a matured compost layer 18 through a diffusion pipe 17 to be deodorized.

Description

DETAILED DESCRIPTION OF THE INVENTION In the treatment of malodorous gas containing odorous components such as ammonia and hydrogen sulfide, deodorization using aged compost and 1[11 deodorization methods (lI-combination), making use of the characteristics of each, can be carried out as a whole. This article relates to a deodorizing method that performs sufficient deodorization.

It has been recognized that aged compost obtained by fermenting conventional sewage sludge compost-8 is highly effective in deodorizing, and a deodorizing device using compost as a deodorizing agent has been proposed. However, all of these were deodorized using a single deodorizing device using compost, so the fact that some of the many odor components cannot be sufficiently deodorized with compost is ignored, and sufficient deodorizing effects are not achieved. In many cases, it was not possible.

The purpose of the present invention is to provide a completely complete deodorizing method by rationally combining the fully open deodorizing method for aged compost with other deodorizing methods.

The following description will be given based on an uninvented ft example.

Aged compost made by fermenting sewage sludge, livestock waste, etc. is known to have a deodorizing effect, and it has been proposed to use this aged compost to deodorize foul-smelling gases.

The invention was an improvement in the deodorizing method using aged compost, and the following table shows the results of a deodorizing experiment using aged compost.

In the experiment shown in the table above, multi-component, complex odors were applied to a column filled with aged compost to a height of 100α at a flow rate of 0.5 cII/Se.
The analysis results after 20 days when aerated at C were shown. In other words, aged compost has a considerable deodorizing effect on the highly polar ammonia, hydrogen sulfide, and methyl mercaptan, but it has no deodorizing effect on the less polar methyl sulfide and methyl disulfide. found.

Therefore, when using aged compost as a deodorizing agent, consider this point and combine other deodorizing methods for components that cannot be deodorized with aged compost to achieve a sufficient overall deodorizing effect. It is necessary to obtain it.

An embodiment of the invention will be explained with reference to FIG.

The gas to be processed 1Fi is guided to a humidifier (or dehumidifier) 3 via a blower 2, and the humidity of the gas to be processed is adjusted. This is to maintain the moisture content of the aged compost in the next stage deodorizing tank 4 at a predetermined value, and can be omitted when the humidity of the gas to be treated is always maintained within an appropriate range. Most of the ammonia, hydrogen sulfide, methyl mercaptan, and a portion of methyl sulfide, methyl disulfide, etc. in the gas to be treated are removed by the aging compost, and then led to the activated carbon tank 5 in the subsequent stage. By contacting the gas to be treated with the foil charcoal, most of the odor components are removed, and the odor is deodorized to below the limit that can be detected by the sense of smell.

Due to the use of activated carbon in the latter stage, activated carbon does not have the effect of removing blister against highly polar substances such as ammonia, but has a large absorption capacity t for substances with low polarity such as methyl disulfide. I can do it. In other words, according to the method shown in Figure 1, it is possible to take advantage of the respective characteristics of aged compost and activated carbon, and not only can sufficient deodorization be performed as a whole, but also the activated carbon It is also possible to extend the lifespan.

FIG. 2 is a block diagram showing a second embodiment according to the invention. The gas to be treated 11 is guided through a blower 12 to an oxidation cleaning tower 13 using sodium hypochlorite. The sodium hypochlorite solution is sprayed from the upper part of the washing tower by the pump 141C and is used for circulation. At this time, the washing tower may be a simple spray tower or a packed tower filled with Raschig rings or the like. In addition, it is desirable to maintain the concentration of sodium hypochlorite at 100 to soo ppm in terms of effective chlorine concentration.
adjusted by. When the pH of the solution is on the acidic side, the oxidizing power is strong, but a large amount of oxidizing chlorine such as chlorine gas is generated from the solution, whereas on the alkaline side, the oxidizing power of methyl disulfide is small, but the oxidizing power of methyl disulfide is small. Since the pH is weak, it is desirable to keep the pH in the neutral range of 6 to 8. At this time, a small amount of oxidizing chlorine generated and odor components remaining without being oxidized are removed by the subsequent aging compost layer 18).

Aged compost may be filled into a deodorizing tank as shown in Figure 1, but if the aeration rate is increased rapidly, the deodorizing effect of aged compost will be weakened, so if the amount of gas to be treated is large, It is preferable to introduce the gas to be treated (through the diffuser pipe 17) into the stacked layer of the ripening combustor as shown in FIG.

If the matured compost layer is allowed to dry out too much, its deodorizing effect will decrease, so measures such as sprinkling with water are required depending on the situation.

In the case of non-invention, most of the ammonia, methyl mercaptan, methyl sulfide, methyl disulfide, hydrogen sulfide, trimethylamine, etc. contained in the gas to be treated are oxidized with sodium hypochlorite. After oxidation cleaning,
Since residual odor components such as hydrogen sulfide and the generated oxidizing chlorine can be removed by aging compost, a sufficient deodorizing effect can be obtained as a whole.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are block diagrams used when carrying out the deodorizing method of the present invention. 1.11... Gas to be treated 2.12... Blower 3... Humidifier or dehumidifier 4... Aged compost filling tank 5... Activated carbon tank 13... Oxidation absorption tower Sodium salt solution J14・
... Pump 15 ... Overflow pipe 16 ... Supply pipe 17 ... Diffusion pipe 18 ... 1 person outside the aging compost layer ゛

Claims (2)

[Claims] (1) In a deodorizing method that uses the entire aged compost as a deodorizer, the gas to be treated that contains all the odor components is further guided to the activated carbon adsorption layer after passing through the aged compost layer, and the aged compost and activated carbon are separated. A deodorizing method that uses t% to deodorize in stages. (2) In the deodorizing method where all the gas to be treated containing odor components is used as a total deodorizing agent, an absorption tower using sodium hypochlorite is installed before the aging compost layer, and the gas to be treated is converted into sodium hypochlorite. A deodorizing method that is characterized by deodorizing in two stages of aging and composting.