JPS5949856A - Feed water controlling method of wet-type dust collector - Google Patents

Abstract

PURPOSE:To control effectively the water feeding of a wet-type dust collector conforming to a restriction for soot and dust, by discharging circulating suspended matters together with a drain, and feeding water, corresponding in quantity to the discharging water quantity to a water circulating line, and controlling the feeding quantity of a pH adjusting agent. CONSTITUTION:After catching dust and mist of sulfuric acid at the front and rear chambers 12 and 13 of a wet-type dust collector 11, a dust collecting waste water is returned to a circulating water tank 14 and is circulated to the collector 11 after being filtered by a auto-strainer 16. A drain, containing solid matters separated by the strainer 16, is discharged out of the system. Further, an alkaline pH adjusting liquid is injected to a circulating water tank 14 through a pH controlling device 18 to neutralize the circulating water into a prescribed pH. On the other hand, a fresh water is replenished to the tank 14 as the descreased portion of circulating water caused by the drain discharge. Further, the fresh water is intermittently fed as a washing water to the rear chamber 13 of the dust collector 11 by an intermittently acting pump 20.

Description

[Detailed Description of the Invention] The present invention is /! This article relates to a method for controlling water supply in a Type 111 dust collector.

Conventionally, the water supply method for a wet-type Its dust machine was as shown in Figure 1 (Al
Alternatively, the method shown in (13) is adopted. Figure 1 (
A) In the O) method, the dust wastewater discharged from the wet drain dunk 2 is sent to the water treatment equipment, and the treated water from the water treatment equipment is circulated to the collector 1 as washing water. It is something that makes you In addition, as shown in Fig. 1 (in the pigeon method, part of the dust collection drainage stored in the drainage tongue 2 is sent to the water treatment membrane (+ii+, and the amount of this blown water is the same as blow water), and the make-up water d is sent to the circulation tank 3. It is used to replenish and supply the dust collector 1.

However, due to the recent tightening of soot and dust emission regulations for boiler plants, whereas previously the treated gas from the flue gas desulfurization equipment was afterburned before being discharged from the chimney.

4. In order to reduce the concentration of soot and dust from the flue gas stack, a wet dust collector is required to remove the sulfuric acid mist and residual boiler dust carried over from the flue gas desulfurization equipment.
This has led to a demand for the establishment of unprecedented economical water treatment systems.

By the way, the -9 of the boiler plant is 1 (1) and the 4 ([J-type dust 1] installed after the u1 smoke desulfurization equipment^1 is
The aim is to capture the sulfuric acid mist and boiler dust remaining in the outlet gas of the flue gas desulfurization equipment.For this purpose, the wet dusting machine's 1ilB7 (circulation supplied as Iy'3) is ；■Water is enough)・I Toka 1
The concentration of suspended solids contained in it is 1 to have 7 Cal.
At the same time, at the same time, it is necessary to collect sulfuric acid mist having a corrosive effect on the material inside the machine. + of
In order to increase FJj from tJ1 meal, it is necessary to adjust and supply the piJ value. On the other hand, from the condition that the wet collector pμ@ is installed as an end unit of a boiler plant, l! IA type dust collector (+) Minimizes carryover of water mist due to water to prevent deterioration of afterburning efficiency, and also reduces carryover [and suspended solid content in water mist] Therefore, it is necessary to supply circulating water.

Kii and Akira are talking about Lki IIN information (= it was made after talking, and it satisfies the above ``2'' required for the water of wet dust collectors in L to make boiler plants comply with strengthened soot and dust emission regulations. However, at the same time, considering the economical efficiency, 1. Wet collection μ) 2 Cedar, Rabbit 0) Water supply side/1i41')j method 11 is provided.

That is, the non-inventive method is 1 wet type 1 dust collection 1 some 1 to 1 skewer.''1. Ruj
ljl Wash the exhaust dust again and add purified water from 1 to 1! i+! Circulation of the circulating water line that supplies the four types of Nido machines 5. lj Suspended solids contained in the water are removed from the system as drenin 4
．． It l+seshime, its drain [according to 44~]
1 water to the circulating jγ3 water line, and the above circulating water line 7.
This is a water supply system Wll+ method for a wet type dust collector, characterized in that the supply M of the W product is controlled by adjusting p supplied to the circulating water line according to the detected value of p I-(of p I-(p) of j(p)1.

Below, 7) IB Referring to Figure 2, the uninvented -¥li+4
Explain an example.

FIG. 2 is a flowchart of a wet dust collector system employing the water supply control method according to the invention.

In the figure, 11 is /! ii! It is a type dusting machine (1), and there are 1111 chambers 12 and a rear chamber 13 inside.
ing. Then, the exhaust gas exiting the flue gas desulfurization device passes through the dust collector JXAtz in the order of the front chamber 12 and the rear chamber 13 as shown by arrows in the figure. 14 is a circulating water tank. A 4F water circulating water pump 15 stored in the circulating water tank 14 continuously sprays the water into the front chamber 12 and rear chamber 13 of the wet dust collector 11 via an auto strainer 16. . The sprayed cleaning water in the front chamber 12 and the rear chamber 13 collects boiler dust and sulfuric acid mist contained in the exhaust gas, and returns to the circulating water tank 14 through separate routes as dust collection wastewater. Therefore, although the circulating water flowing from the circulating water tank 14 to the auto-strainer 16 has a high concentration of suspended solids, the auto-strainer I6 filters out the solids, and the 1112 purified water has sufficient dust collection ability. As a wet gathering', '4 machines 1
1. Me'-tost 1/-
160) Is the drain contaminated with the solids separated by I6 an auto-strainer? This drain flow M is controlled to a constant flow i11 by an automatic flow rate control device 17 provided in the drain piping. To adjust the value, add NaOH solution or Ca(01-'L solution'G)7 to rim lt+ the collected sulfuric acid mist.
Luca'J □ni'l: pH%I,! I! J47rt is injected into Flit tE4 fl Senkan water tank 14 and 2
). This p I''+i14. i The liquid regulating flow M returns to the circulating water tank 14 and the pH value of the water is adjusted to the pH value of the water. It is controlled so that it is neutralized. In this case, the acid +7.t:ffJ: becomes stronger as well.
Dust collection and drainage pI (values should be recorded in p II 8, 1.1 and 0) shall be used as reference information. R
Solution 0) It is designed to stop p41 decrease by μJ5. On the other hand, as the drain water from the auto-strainer 6 (2, therefore, circulating water: 5) decreases, new water (water for industrial use) is replenished into the water tongue 14 to compensate for the decrease. It has become so. That is, (l+'i Kansui Kunkutan is provided with a water level adjustment device 19, and when the water level of the circulating water tank 14 decreases, V is adjusted until the predetermined water level is restored.
``Replenish water.Also, use a timer to intermittently produce fresh water (industrial water).
0, the cleaning water is supplied intermittently (every 5 to 10 minutes/2 minutes) to the rear chamber 13 where the dust load in the wet type I1 is low.

1] 2) According to the method of water supply control in the wet dust collector system shown in Fig. 2, the cleaning water is supplied to the dust collector (2) The circulating port where the suspended solids concentration in the water is controlled below a fixed value. At the same time, the p l-I value can be maintained within a predetermined range.In addition, new po (neutral and By adopting a method of purifying z1L with industrial water (with a low concentration of water), water mist due to carryover will be reduced.
・Can be made into a stand-alone compact facility.

As described in detail above, according to the present invention, an effective wet-type soot that is suitable for boiler plants where soot and dust regulations have been strengthened]
This method can provide several water supply control methods.

[Brief explanation of the drawing]

i1', Figure 1 (N and (phrase) are explanatory diagrams showing the conventional water supply method for wet dust collection, respectively, and Figure 2 shows a wet dust collection system that adopts the water supply control method that is an embodiment of the present invention. In the flowchart, 1). 11...l!11] Formula collection common machine I2...target chamber, 13. Rear chamber 14...circulating water tank, 15 pump 16...auto strainer 17... Flow, control device 18...pH control device 19...water level adjustment device 2θ...pump

Claims (1)

[Claims] The dust collection wastewater discharged from the wet dust collector is supplied to the wet dust collector again as washing water.The suspended solids contained in the circulating water of the circulating door water line are discharged outside the system as a drain. The wet type dust collector is characterized in that the circulating water line is replenished with a new pn according to the detected value of the circulating water, and a supply meter of pHRIM chemicals to be supplied to the circulating water line is controlled according to the detected value of the pn of the circulating water. Water supply control method.