JPH0356771B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to an exhaust gas purification method for adsorbing and removing odors and gases discharged into the atmosphere from sources of odors and gases such as factories, thereby eliminating so-called causes of pollution. BACKGROUND OF THE INVENTION Odors and gases are mixed into the gas discharged into the atmosphere from factory chimneys, etc., and this causes pollution. Conventionally, methods for treating the above-mentioned odors and gases can be roughly divided into combustion methods, gas phase treatment methods using the oxidizing action and masking effect of ozone, and adsorption methods using activated carbon or the like. Problems to be Solved by the Invention However, the combustion method heats and oxidizes odor and gas components, resulting in air pollution such as NOX and SOX.
Further, catalyst poisons such as sulfur, halogen tar, and metals degrade performance and shorten life, and furthermore, when the throughput is large, a huge amount of energy is required. In addition, in the gas phase treatment method using ozone,
It has no treatment effect on ammonia, and if ozone is used in excess, activated carbon is required to remove the toxic residual ozone, which is expensive. Furthermore, in the adsorption method using activated carbon, activated carbon cannot adsorb hydrophilic odors and gases, so unless these hydrophilic odors and gas components are removed in advance, a stable adsorption effect in a low concentration range cannot be expected. In addition, hydrogen sulfide is the main source of odors and gases emitted from factories, etc., and aldehydes, ammonia, etc. are also responsible. On the other hand, although activated carbon is effective in adsorbing organic compounds with relatively large molecular weights, it is not very effective in adsorbing hydrogen sulfide and the like with small molecular weights as mentioned above. In addition, all treatment methods are not effective in adsorbing a wide range of odors and gases, so it is necessary to combine treatment methods depending on the type of odors and gases.
There were problems such as complicated processing steps, long processing times, and increased processing costs. Therefore, the present invention uses an adsorbent that can be manufactured easily and at low cost to effectively adsorb and remove various odors and gases in exhaust gas, prevent the occurrence of pollution, and treat It is an object of the present invention to provide a method for purifying exhaust gas that can simplify the process, thereby reducing processing time and processing cost. Means for Solving the Problems The technical means of the present invention for solving the above problems is to use coal flyash and cement as main raw materials, ammonium chloride, potassium chloride, magnesium chloride, sodium chloride, calcium chloride, A charged adsorbent formed by mixing sodium sulfate, citric acid, and cobalt chloride, which is a granulated continuous pore material, is placed in an adsorption tower, and gases from sources of odor and gas are passed through the adsorption tower. , odors, and gases are adsorbed onto the above-mentioned adsorbent. As the above-mentioned adsorbent, ammonium chloride 0.04-0.05%, potassium chloride 0.07-0.095%, magnesium chloride 0.015-0.02 per 1000 kg of coal flyash and 50-200 kg of cement, which are the main raw materials, are used.
%, sodium chloride 0.015-0.02%, calcium chloride 0.015-0.02%, sodium sulfate 0.001-0.002
%, citric acid 0.0005-0.001%, cobalt chloride
Used at a weight ratio of 0.0001 to 0.0002%. Further, when an electromagnetic field is applied, a weight ratio of 5 to 20% kaolinite and 0.001 to 0.01% barium oxide is used, and when potassium permanganate is used, a weight ratio of 0.002 to 0.01% is used. By mixing coal fly ash with an aqueous solution of cement, calcium ion reactions are activated when the cement is in the liquid phase, and humic acid, which is a high molecular compound that inhibits the solidification reaction of cement, is mixed with ammonium chloride, sodium sulfate, and citric acid. The particles of SiO ₂ , Al ₂ O ₃ , MgO, K, and Na, which are the main components of coal fly ash, are reacted with the calcium of the cement to normalize the hydration and setting reaction of the cement. The hardened material, which is solidified by providing permeability to calcium ions in the cement through the action of sodium chloride and potassium chloride, becomes a granulated continuous pore material, which is the opposite of a cement solidified material.
At this time, by reacting calcium chloride with cement, the hydration and setting time of cement can be shortened, and by reacting calcium ions with magnesium chloride, shrinkage of cement can be prevented, and cobalt chloride can be used. Each of the above reactions can be activated by this. The chemical composition of this granulated continuous pore body is SiO ₂ 50-70%;
Al ₂ O ₃ 10-30%, MgO2-3%, CaO10-20%,
Na is 5 to 10%, SiO ₄ Al ₂ O ₄ tetrahedron shares oxygen atoms to form an oxidized ring, and a three-dimensional framework is manufactured by making this continuous, with a pore diameter of 50 Å 300 Å and a specific surface area of 10 m ² /g ~ 15m ² /g, some of the Si in this is replaced with Al, producing a -1 valent charge, which is neutralized by Na ⁺ , K ⁺ ,
It becomes an aluminum silicate compound containing cations such as Ca ⁺⁺ inside. When producing the granulated continuous pore body, an electromagnetic field is applied as necessary, and at this time, kaolinite and barium oxide can prevent a decrease in the sustaining force of the magnetic force when the electromagnetic field is applied. Further, by supporting potassium permanganate on the surface of the granulated continuous pore material, it is possible to prevent odor from being removed and increase the specific surface area of the granulated continuous pore material. Here, if ammonium chloride is less than 0.04%, each component except potassium permanganate will be difficult to dissolve, and if it is more than 0.05%, the strength of the granulated continuous pore material will decrease. If the potassium chloride content is less than 0.07%, the cement's ability to penetrate calcium ions will be poor;
If it exceeds %, not only will it be difficult to dissolve, but the effect of imparting permeability to calcium ions will not improve. If magnesium chloride is less than 0.015%, shrinkage cracks will occur in the granulated continuous pore material, and if it is more than 0.02%, the granulated continuous pore material will expand. sodium chloride
If it is less than 0.015%, the cement's ability to penetrate calcium ions will be poor, and if it is more than 0.02%, it will not only be difficult to dissolve, but the effect of imparting penetration power to calcium ions will not improve. Calcium chloride is 0.015
If it is less than 0.02%, the strength of the granulated continuous pore material cannot be enhanced, and if it is more than 0.02%, there is a risk that the granulated continuous pore material may be destroyed due to water breaking phenomenon. If sodium sulfate is less than 0.001%, the cement cannot be hardened rapidly, and if it is more than 0.002%, the long-term stability of the cement strength is poor. citric acid
If it is less than 0.0005%, each component except potassium permanganate will be difficult to dissolve, and if it is more than 0.001%, the strength of the granulated continuous pore material will decrease. cobalt chloride
If it is less than 0.0001%, it will not be possible to activate the ionic activity of each component except potassium permanganate, and if it is more than 0.0002%, not only will the effect not be improved, but it will also be expensive. In addition, among the kaolinite, barium oxide, and potassium permanganate that are added as needed, if kaolinite is less than 5%, the aluminum component and trace elements will be insufficient, resulting in a decrease in replacement ability, and if it is more than 20%, the mixing ratio will decrease. The effectiveness decreases due to lack of Al ₂ O ₃ . If barium oxide is less than 0.001%, the magnetic force will not persist when an electromagnetic field is applied, and if it is more than 0.01%, it will not only be less effective but also expensive. potassium permanganate
Less than 0.002%, the oxidizing ability is inferior, and even more than 0.01% does not improve the effect. In addition, if the SiO ₂ and Al ₂ O ₃ components contained in the coal fly ash, which is the main raw material, are insufficient, they can be replenished with bentonant or clay, and if it is necessary to increase the strength of the granulated continuous pore material. It is sufficient to increase the amount of cement and use sand as aggregate.
In this case, it is desirable to use 20 to 40% of sand per 1000 kg of coal fly ash. Effect The above adsorbent is formed into a granulated continuous pore body with micropores and macropores of 50 Å to 300 Å.
Water and gas can be circulated well, and the voids, that is, the specific surface area as a whole are large, and the liquid phase,
It has adsorption ability for both gas phase and electrically captures cations such as Na ⁺ , K ⁺ , and Ca ⁺⁺ by generating -1 valent charge and neutralizing this charge. By passing the exhaust gas containing odors and gases through the adsorption tower containing this adsorbent, the odors and gases contained in the gas connected to the adsorbent are absorbed into the numerous micro- and macro-pores of the adsorbent. It can be absorbed and absorbed. By using an adsorbent with the above properties, it is possible to effectively adsorb not only hydrophobic neutral substances in exhaust gas but also various malodors and gases such as acidic malodorous components, salty malodorous components, and hydrophilic substances. I can do it. The reaction formula of the above adsorbent for alkaline malodorous components and acidic malodorous components is shown below. [Reaction formula for alkaline malodorous components] NH ₃ +A-H→NH ₄ -A (CH ₃ ) ₃ +A-H→(CH ₃ ) ₃ NH-A H ₂ S+B-OH→B-HS+H ₂ O CH ₃ SH+B- OH→CH ₃ S−B+H ₂ O [Reaction formula for acidic malodorous components] NO+KMnO ₄ →KNO ₃ +MnO ₂ 3H ₂ S+8KMnO ₄ →3K ₂ SO ₄ +8MnO ₂ +2KOH+2H ₂ O CH ₃ SH+2KMnO ₄ →CH ₃ SO ₃ 2MnO ₂ +KOH 3(CH ₃ ) ₂ S + 4KMnO ₄ +2H ₂ O → 3(CH ₃ ) ₂ SO ₂ +4MnO ₂ +4KOH The adsorbent used in the present invention can be easily and inexpensively prepared by mixing the material into an aqueous solution and then drying it. Furthermore, the treatment process can be simplified by being able to effectively adsorb the various odors and gases mentioned above. Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic explanatory diagram showing an embodiment of the present invention. In Figure 1, 1 is the source of odor and gas; 2 is the source of odor and gas;
Reference numeral 4 denotes a blower that sends gas from the source 1 through the exhaust pipe 3, and 4 an adsorption tower filled with an adsorbent 5 through which the gas sent by the blower 2 through the exhaust pipe 3 passes. Then, the gas from the source 1 is caused to flow into the adsorption tower 4 through the exhaust pipe 3 by the blower 2, and the adsorbent 5 in the adsorption tower 4 adsorbs the odor and gas in the gas, and the treated gas is Emitted into the atmosphere from chimneys, etc. To explain the details of the above adsorbent 5, coal fly ash 1000Kg, Portland cement
130Kg, 300Kg of sand, 400g of ammonium chloride,
Potassium chloride 900g, magnesium chloride 175g, sodium chloride 175g, calcium chloride 175g, sodium sulfate 15g, citric acid 7.5g, cobalt chloride
It was selected to have a blending ratio of 1.5g. Adsorbent 5 was manufactured in the following manner using the above blending ratio. Dissolve 1000 kg of coal fry ash, 400 g of mixed powdered ammonium chloride and 600 g of potassium chloride in 150 kg of water, and mix with a mixer.
It was dried at 20°C (which can be appropriately selected between 5 and 80°C) to neutralize the ions adsorbed on the coal fly ash. Next, as a secondary treatment, 300 kg of sand was added to the coal fly ash after the primary treatment and mixed, followed by 130 kg of Portland cement.
Kg was added and mixed. Next, mix 300 g of powdered potassium chloride and 175 g of magnesium chloride.
g, sodium chloride 175g, calcium chloride 175g
g, 15 g of sodium sulfate, 7.5 g of citric acid, and 1.5 g of cobalt chloride are dissolved in 100 g of water to make an aqueous solution, and this aqueous solution is added by spraying into the mixer during the above mixing, mixed and heated to 80°C (5 g). ~80℃
(the curing process can be accelerated by increasing the temperature). This made it possible to form a granulated continuous pore body (potassium permanganate attached to the surface of the granulated continuous pore body did not affect the adsorption effect itself, so it was not attached). The granulated continuous pore body _which is the adsorbent ₅ produced in this manner is shown schematically in _FIG . It has a three-dimensional framework structure in which oxygen atoms are shared to form an oxygen ring and this is continuous, and the hole 5a
(small) and 5b (large) had a diameter of 50 Å to 300 Å, and a specific surface area of 10 to 15 m ² /g. Since the specific surface area of coal fly ash is 0.9 to 1 m ² /g, the above adsorbent 5 was able to significantly increase it. Next, a test example of the present invention using a granulated continuous pore material as the adsorbent 5 and a comparative test example using conventional activated carbon will be explained. As mentioned above, hydrogen sulfide is a malodorous substance that is the source of odors and gases emitted from factories and the like, so an adsorption test for hydrogen sulfide was conducted in the following manner. [Test equipment] Detler bag (100) filled with sample gas
Connect the blower to the column (22mm
Ф), the column was packed with adsorbent 5 or activated carbon, and the column was connected to a flow meter. [Test conditions] Sample gas: H ₂ S Gas concentration: Two types: 150 ppm and 1100 ppm Gas flow rate: 10 ml/sec Amount of adsorbent 5 or activated carbon packed into the column: Two types: 10 g and 20 g Column temperature: 25°C ± 1 C. Superficial velocity: 2.6 cm/sec The results of the H ₂ S breakthrough time test under the above test conditions and equipment are shown in the table below.

[Table] As is clear from the above test results, gas concentration
At 1100ppm, 5 adsorbent and 10 activated carbon each.
Comparing the breakthrough times when using activated carbon, it was 1.4 hours when using adsorbent 5, and 5 hours when using adsorbent 5. It can be inferred that the adsorption effect is significantly better than that of activated carbon in other cases as well. Also, the adsorbent 5
It has been confirmed through tests that it can also adsorb odors and gases other than hydrogen sulfide, examples of which are shown in the table below.

[Table] As shown above, the gas containing the odor and gas from the source 1 is passed through the adsorbent 5 of the adsorption tower 4 by the blower 2, and the odor and gas are adsorbed by the adsorbent 5, making it odorless and harmless and releasing it into the atmosphere. air pollution, etc.
The causes of pollution can be removed. In order to apply an electromagnetic field to the adsorbent 5 used in the present invention, it is sufficient to add 200 kg of kaolinite and 1 kg of barium oxide in the secondary treatment step and apply an electromagnetic field during the reaction of the secondary treatment step. The above adsorption effect can be further improved by applying an electromagnetic field to. In addition, after the above secondary treatment, as a tertiary treatment, 50 g of powdered potassium permanganate was dissolved in 100 g of water, mixed with a mixer, and heated at 20°C (5 to 80°C can be selected as appropriate). By drying, an adsorbent supporting potassium permanganate can be produced, thereby preventing the release of gas and odor. The above-mentioned adsorbent 5 absorbs odor and gas concentration in the gas,
The amount to be used may be appropriately selected depending on the contact time with the gas, etc. Effects of the Invention In summary, according to the present invention, the adsorbent used can be easily produced at low cost by mixing the material in an aqueous solution and then drying the adsorbent. In addition, this adsorbent is formed into a granulated continuous pore body with micropores and macropores, and has adsorption performance for both liquid and gas phases, and is also electrically charged. By passing exhaust gas containing various odors and gases through the tower, they can be effectively adsorbed, thereby simplifying the flow system. Therefore, the time required for processing can be shortened, and processing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the exhaust gas purification method of the present invention, and FIG. 2 is a schematic diagram showing an adsorbent used in the present invention. 1... Source of odor and gas, 2... Blower, 4
...Adsorption tower, 5...Adsorbent.

Claims (1)

[Claims] 1 Coal fly ash and cement, which are the main raw materials, ammonium chloride, potassium chloride, magnesium chloride, sodium chloride, calcium chloride,
A charged adsorbent formed by mixing sodium sulfate, citric acid, and cobalt chloride, which is a granulated continuous pore material, is placed in an adsorption tower, and gases from sources of odor and gas are passed through the adsorption tower. , odor, and gas are adsorbed by the above-mentioned adsorbent.