JP3053482B2 - Method for controlling injection amount of aluminum compound in treatment of wastewater containing fluorine and aluminum and fluorine removing device - Google Patents
Method for controlling injection amount of aluminum compound in treatment of wastewater containing fluorine and aluminum and fluorine removing deviceInfo
- Publication number
- JP3053482B2 JP3053482B2 JP3331522A JP33152291A JP3053482B2 JP 3053482 B2 JP3053482 B2 JP 3053482B2 JP 3331522 A JP3331522 A JP 3331522A JP 33152291 A JP33152291 A JP 33152291A JP 3053482 B2 JP3053482 B2 JP 3053482B2
- Authority
- JP
- Japan
- Prior art keywords
- fluorine
- wastewater
- aluminum
- concentration
- aluminum compound
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5209—Regulation methods for flocculation or precipitation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
- C02F1/5245—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/12—Halogens or halogen-containing compounds
- C02F2101/14—Fluorine or fluorine-containing compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/18—Nature of the water, waste water, sewage or sludge to be treated from the purification of gaseous effluents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/001—Upstream control, i.e. monitoring for predictive control
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/003—Downstream control, i.e. outlet monitoring, e.g. to check the treating agents, such as halogens or ozone, leaving the process
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/40—Liquid flow rate
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Removal Of Specific Substances (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は、弗素(本明細書におい
ては「弗素イオン」を意味する)及びアルミニウム(本
明細書においては「アルミニウムイオン」を意味する)
を含有する廃水処理におけるアルミニウム化合物注入量
の制御方法に関するものであり、更に詳しくは、弗素及
びアルミニウムを含有する廃水中の弗素分をアルミニウ
ム化合物により除去する廃水処理方法において、該アル
ミニウム化合物の注入量を制御する方法に関する。BACKGROUND OF THE INVENTION The present invention relates to fluorine (herein "fluoride ion") and aluminum (herein "aluminum ion").
More particularly, the present invention relates to a wastewater treatment method for removing a fluorine content in wastewater containing fluorine and aluminum by an aluminum compound, and more particularly to a method for controlling the injection amount of the aluminum compound. Related to the method of controlling.
【0002】[0002]
【従来の技術】石炭火力発電所において生ずる排煙脱硫
廃水(以下、「脱硫廃水」と言う)には、弗素分が含有
されており、アルミニウム化合物を使用して、かかる廃
水中の弗素分を水酸化アルミニウムと共沈させ、共沈沈
澱物の形で除去する廃水処理方法が広く行われている。
ここで、「アルミニウム化合物」とは、上記の「水酸化
アルミニウム」を生成することができるものであれば何
でもよく、硫酸アルミニウム、ポリ塩化アルミニウム、
明礬等を例として挙げることができ、溶液状で使用して
も固体状で使用してもよい。これらのアルミニウム化合
物の中でも硫酸アルミニウムを使用するのが一般的であ
る。2. Description of the Related Art Flue gas desulfurization wastewater (hereinafter referred to as "desulfurization wastewater") generated in a coal-fired power plant contains fluorine, and an aluminum compound is used to reduce the fluorine content in such wastewater. BACKGROUND ART Wastewater treatment methods for coprecipitating with aluminum hydroxide and removing in the form of coprecipitated precipitates are widely used.
Here, the “aluminum compound” may be anything that can produce the above “aluminum hydroxide”, such as aluminum sulfate, polyaluminum chloride,
Alum or the like can be mentioned as an example, and it may be used in the form of a solution or in the form of a solid. Of these aluminum compounds, aluminum sulfate is generally used.
【0003】しかしながら、石炭火力発電所における脱
硫廃水中の弗素濃度は、例えば、発電のために使用する
石炭の種類(炭種)や排煙脱硫装置の方式(スート分離
方式やスート混合方式)、更には例え炭種が同一であっ
ても発電負荷量によって異なるのが一般的である。[0003] However, the fluorine concentration in the desulfurization wastewater in a coal-fired power plant depends on, for example, the type of coal (coal type) used for power generation, the type of flue gas desulfurization equipment (soot separation method or soot mixing method), Furthermore, even if the type of coal is the same, it generally differs depending on the power generation load.
【0004】従来、このような弗素含有廃水の弗素分除
去装置を用いた処理は、手動により薬品量の調節を行う
のが実情であった。Heretofore, in the treatment using such a fluorine-removing apparatus for the fluorine-containing wastewater, the actual amount of the chemical has been adjusted manually.
【0005】図4は、一例として、石炭火力発電所の運
転時間の経過に伴う脱硫廃水の弗素濃度の変化をモデル
的に表したグラフ図である。この図の横軸は運転時間を
表し、縦軸は弗素濃度を表す。脱硫廃水中の弗素濃度
は、図4に示されるように、運転時間の経過とともに変
動するが、従来、弗素の分析は時間と労力を要するの
で、予想弗素濃度(A)を基凖にして、一定注入率で硫
酸アルミニウム等のアルミニウム化合物を注入しつつ弗
素分除去装置を運転する場合が多かった。FIG. 4 is a graph showing, by way of example, a model representation of the change in the fluorine concentration of the desulfurization wastewater with the elapse of the operation time of a coal-fired power plant. The horizontal axis of this figure represents the operation time, and the vertical axis represents the fluorine concentration. As shown in FIG. 4, the fluorine concentration in the desulfurization wastewater fluctuates with the elapse of the operation time. However, conventionally, the analysis of fluorine requires time and labor, and therefore, based on the expected fluorine concentration (A), In many cases, the fluorine removing device was operated while injecting an aluminum compound such as aluminum sulfate at a constant injection rate.
【0006】[0006]
【発明が解決しようとする問題点】この場合、廃水中の
実際の弗素濃度が予定弗素濃度(A)より低濃度(C)
〔即ち、濃度変動の山が下〕であれば、硫酸アルミニウ
ムの過剰注入となり、ランニングコストの上昇を招くこ
ととなる。逆に、実際の弗素濃度が予定弗素濃度(A)
より高濃度(B)〔即ち、濃度変動の山が上〕であれ
ば、アルミニウム化合物注入量が不足することとなり、
弗素分除去の効率が低下し、処理水質の悪化を招き、放
流基準水質を満足できなくなる。従来、かかる不都合が
多々見られていた。In this case, the actual fluorine concentration in the wastewater is lower than the expected fluorine concentration (A) (C).
If [the peak of the concentration fluctuation is below], excessive injection of aluminum sulfate is caused, which leads to an increase in running cost. Conversely, the actual fluorine concentration is the expected fluorine concentration (A)
If the concentration (B) is higher (that is, the peak of the concentration fluctuation is higher), the amount of the aluminum compound injected becomes insufficient,
The efficiency of fluorine removal is reduced, and the quality of treated water is deteriorated, so that the discharge standard water quality cannot be satisfied. Conventionally, such inconveniences have been frequently observed.
【0007】また、脱硫廃水中にはアルミニウム分(ア
ルミニウムイオン)が存在し、このアルミニウム分が弗
素除去に有効利用されうることも明らかとなっている。
しかしながら、脱硫廃水中のアルミニウム濃度も排煙脱
硫装置の運転状況や使用する石炭の種類等によって異な
ってくるのが一般的である。[0007] It has also been clarified that aluminum (aluminum ions) is present in the desulfurization wastewater, and that this aluminum can be effectively used for removing fluorine.
However, the aluminum concentration in the desulfurization wastewater also generally varies depending on the operating conditions of the flue gas desulfurization unit, the type of coal used, and the like.
【0008】このため、脱硫廃水中のアルミニウム分を
弗素除去に有効利用する場合は、或る基準の脱硫廃水中
含有アルミニウム濃度(通常は、計画値)を想定し、不
足分のアルミニウム化合物注入量を設定することが一般
的である。この方法では、前述と同様に、アルミニウム
化合物の過不足が生じ、運転経費の上昇、処理水質の安
定化が図れない等の問題が生じていた。For this reason, when the aluminum content in the desulfurization wastewater is to be effectively used for removing fluorine, a certain standard of the aluminum concentration in the desulfurization wastewater (generally, a planned value) is assumed, and the aluminum compound injection amount of the shortage is assumed. It is common to set In this method, as described above, there are problems such as excess and deficiency of the aluminum compound, an increase in operating cost, and an inability to stabilize the quality of treated water.
【0009】しかも、上記の場合、脱硫廃水中のアルミ
ニウム濃度が弗素濃度と同調して変動するとは限らず、
殆ど相関関係の無い状態で変化することが多い。従っ
て、廃水中の弗素濃度のみの測定では、適正なアルミニ
ウム化合物注入量が決定できない等、脱硫廃水処理装置
は従来の総合廃水処理装置とは異なった運転管理を必要
とする。Moreover, in the above case, the aluminum concentration in the desulfurization wastewater does not always fluctuate in synchronization with the fluorine concentration.
It often changes with little correlation. Accordingly, the desulfurization wastewater treatment apparatus requires an operation management different from that of the conventional general wastewater treatment apparatus, for example, the measurement of only the fluorine concentration in the wastewater cannot determine the appropriate amount of the aluminum compound to be injected.
【0010】処理水質の安定化を図ろうとすれば、アル
ミニウム化合物の過剰注入を余儀無くされ、アルミニウ
ム化合物消費量の増加に伴うコスト増大の問題を生じて
いた。また、流入廃水の弗素やアルミニウムの濃度変動
を吸収し、流入廃水の性状を極力均一化させるために、
前段に充分大容量の貯留槽とその為の均一化設備を設け
る必要が有った。In order to stabilize the quality of the treated water, an excessive injection of the aluminum compound has been inevitable, resulting in a problem of an increase in cost due to an increase in the consumption of the aluminum compound. In addition, in order to absorb fluctuations in the concentration of fluorine and aluminum in influent wastewater and to make the properties of influent wastewater as uniform as possible,
It was necessary to provide a sufficiently large storage tank and a homogenizing facility for it in the former stage.
【0011】従って、本発明は、上記の諸問題を解決せ
んとするものであり、弗素含有廃水の弗素分除去処理に
おいて、アルミニウム化合物注入量を必要最小限に留め
ることをその主目的とし、更には処理水質の安定化をも
図らんとするものである。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and the main object of the present invention is to minimize the amount of aluminum compound to be injected in a fluorine-containing wastewater treatment process. Aims to stabilize the quality of treated water.
【0012】かかる諸問題の解決に当たっては、弗素分
除去装置へ流入する廃水流量の変動、流入廃水中の弗素
濃度の変動及び流入廃水中のアルミニウム濃度の変動に
対応したアルミニウム化合物注入量の制御手段を案出す
ること、アルミニウム化合物の注入量が過剰とならない
ように必要最小限とする手段を案出すること、更には、
廃水の弗素イオン濃度及びアルミニウムイオン濃度の変
動に伴う処理水質の変動を目標値と比較してフィードバ
ックするにしても、廃水処理が少なくとも反応→pH調
整→沈澱分離というプロセスを踏むために制御時定数が
桁違いに大きいという問題を解決する手段を案出するこ
とが必要であった。In order to solve the above-mentioned problems, a control means for controlling the amount of the aluminum compound injected corresponding to the fluctuation of the flow rate of the wastewater flowing into the fluorine removing device, the fluctuation of the fluorine concentration in the wastewater and the fluctuation of the aluminum concentration of the wastewater. And devising means for minimizing the necessary amount so that the injection amount of the aluminum compound is not excessive,
Even if fluctuations in treated water quality due to fluctuations in the fluoride ion concentration and aluminum ion concentration of wastewater are compared with target values and fed back, the wastewater treatment must be controlled at least in order to go through a process of reaction → pH adjustment → precipitation and separation. It was necessary to devise a means to solve the problem that was significantly larger.
【0013】[0013]
【問題点を解決するための手段】本発明者等は、かかる
観点から鋭意検討した結果、本発明を完成するに到っ
た。Means for Solving the Problems The present inventors have made intensive studies from such a viewpoint, and as a result, have completed the present invention.
【0014】即ち、本発明によれば、流入する廃水の流
量を検出する廃水流量検出器、流入廃水の弗素濃度を検
出する廃水弗素濃度分析計、及び流入廃水のアルミニウ
ム濃度を検出する廃水アルミニウム濃度分析計を備えた
弗素及びアルミニウム含有廃水から弗素分を除去する弗
素分除去装置の制御方法において、前記廃水弗素濃度分
析計からの弗素濃度信号により、弗素分除去に必要なア
ルミニウム濃度を予め定めた計算式又は乗算係数により
算出し、この算出必要アルミニウム濃度から前記廃水ア
ルミニウム濃度分析計からのアルミニウム濃度信号を減
算し、更に前記廃水流量検出器からの流入廃水流量信号
を乗算する演算回路によりアルミニウム化合物注入量を
演算出力する弗素及びアルミニウム含有廃水処理におけ
るアルミニウム化合物注入量の制御方法が提供される。That is, according to the present invention, a wastewater flow rate detector for detecting the flow rate of inflow wastewater, a wastewater fluorine concentration analyzer for detecting the fluorine concentration of inflow wastewater, and a wastewater aluminum concentration for detecting the aluminum concentration of inflow wastewater In a control method of a fluorine removing device for removing fluorine from waste water containing fluorine and aluminum provided with an analyzer, an aluminum concentration required for fluorine removal is predetermined by a fluorine concentration signal from the fluorine concentration analyzer for waste water. An aluminum compound is calculated by a calculation formula or a multiplication coefficient, by subtracting the aluminum concentration signal from the wastewater aluminum concentration analyzer from the calculated required aluminum concentration, and further multiplying by the inflow wastewater flow signal from the wastewater flow detector. Aluminization in the treatment of wastewater containing fluorine and aluminum for calculating and outputting the injection amount The method of the object injection amount is provided.
【0015】この弗素及びアルミニウム含有廃水処理に
おけるアルミニウム化合物注入量の制御方法において、
処理水の目標弗素濃度値をゼロでは無い排水許容限度内
の正の値に設定し、該目標弗素濃度値と処理水の弗素濃
度測定値との偏差の極性及びその大きさによりアルミニ
ウム化合物注入量の演算出力を補正する為の乗算係数を
算出する演算回路を設け、流入廃水流量を積算する積算
回路による積算値が前記処理水の弗素濃度検出位置まで
の前記弗素分除去装置の実効滞留容積値に達したと比較
回路が判断する毎に、前記補正乗算係数を演算・修正す
ると共に前記積算値をリセットする機能を前記弗素分除
去装置が備え、前記アルミニウム化合物注入量に前記補
正乗算係数を乗算した値をアルミニウム化合物注入量コ
ントローラーのリモート設定値としてアルミニウム化合
物注入量を制御するのが好ましい。In the method for controlling the amount of aluminum compound injected in the treatment of waste water containing fluorine and aluminum,
The target fluorine concentration of the treated water is set to a positive value within the allowable limit of drainage which is not zero, and the polarity of the deviation between the target fluorine concentration value and the measured fluorine concentration of the treated water and the magnitude thereof indicate the amount of the aluminum compound injected. An arithmetic circuit for calculating a multiplication coefficient for correcting the arithmetic output of the above is provided, and the integrated value obtained by the integrating circuit for integrating the inflow wastewater flow rate is an effective retention volume value of the fluorine component removing device up to the fluorine concentration detection position of the treated water. Each time the comparison circuit determines that the temperature has reached the above, the fluorine component removing device has a function of calculating and correcting the correction multiplication coefficient and resetting the integrated value, and multiplies the aluminum compound injection amount by the correction multiplication coefficient. It is preferable to control the aluminum compound injection amount by using the set value as a remote setting value of the aluminum compound injection amount controller.
【0016】更に、本発明によれば、アルミニウム化合
物を注入する反応槽を有する一次処理装置及び二次処理
装置を包含する弗素分除去装置であって、前記反応槽の
上流に流入廃水流量検出器並びに廃水弗素濃度分析計及
び廃水アルミニウム濃度分析計を備え、前記一次処理装
置と前記二次処理装置の間か前記二次処理装置の下流に
処理水弗素濃度分析計を所要に応じて備えており、前記
した本発明のアルミニウム化合物注入量の制御方法の実
施態様のいづれかに従った制御を行うための演算手段を
備え、更に、前記演算手段による演算結果に応じてアル
ミニウム化合物を前記反応槽に注入するためのアルミニ
ウム化合物注入手段を備えていることを特徴とする弗素
分除去装置も提供される。Further, according to the present invention, there is provided a fluorine removing device including a primary treatment device and a secondary treatment device having a reaction tank for injecting an aluminum compound, wherein a flow rate detector of an inflowing wastewater is provided upstream of the reaction tank. And a wastewater fluorine concentration analyzer and a wastewater aluminum concentration analyzer, and a treated water fluorine concentration analyzer is provided between the primary treatment device and the secondary treatment device or downstream of the secondary treatment device as required. Computing means for performing control according to any one of the above-described embodiments of the method for controlling the amount of aluminum compound injected according to the present invention, and further comprising: injecting an aluminum compound into the reaction tank in accordance with a result of computation by the computing means. A fluorine compound removing device provided with an aluminum compound injecting means for removing the fluorine.
【0017】本発明においても、上述したように、「ア
ルミニウム化合物」とは、「水酸化アルミニウム」を生
成することができるものであれば何でもよく、硫酸アル
ミニウム、ポリ塩化アルミニウム、明礬等を例として挙
げることができ、溶液状で使用しても固体状で使用して
もよい。本発明においても、硫酸アルミニウムを使用す
るのが一般的である。In the present invention, as described above, the "aluminum compound" is not limited as long as it can produce "aluminum hydroxide", and examples thereof include aluminum sulfate, polyaluminum chloride, and alum. And it may be used in the form of a solution or a solid. Also in the present invention, it is common to use aluminum sulfate.
【0018】以下、被処理廃水として脱硫廃水の場合を
中心として、本発明を具体的且つ詳細に説明する。Hereinafter, the present invention will be described specifically and in detail, focusing on desulfurization wastewater as the wastewater to be treated.
【0019】先ず、弗素分除去装置へ流入する廃水の弗
素濃度(F)を測定し、弗素除去に必要なアルミニウム
濃度(即ち、アルミニウム量、これを仮に「全アルミニ
ウム量」とする)を実機の運転で得られた計算式〔F
(x)〕又は簡易な乗算係数(α)により、上記弗素濃
度に応じて算出し、場合によっては更に流入廃水中のア
ルミニウム濃度(Al’、これを仮に「含有アルミニウ
ム量」とする)を測定し、この値を前記全アルミニウム
量から減算して、注入すべき「不足分アルミニウム量」
を算出し、更にこの「不足分アルミニウム量」をアルミ
ニウム化合物量に換算する。First, the fluorine concentration (F) of the wastewater flowing into the fluorine removal device is measured, and the aluminum concentration required for fluorine removal (that is, the amount of aluminum, which is temporarily referred to as “total aluminum amount”) is measured in the actual machine. The calculation formula [F
(X)] or a simple multiplication coefficient (α) to calculate according to the above-mentioned fluorine concentration, and in some cases, further measure the aluminum concentration (Al ′, which is temporarily referred to as “aluminum content”) in the inflow wastewater. Then, this value is subtracted from the total aluminum amount, and the “deficient aluminum amount” to be injected is set.
Is calculated, and this “deficient aluminum amount” is converted to an aluminum compound amount.
【0020】また、流入廃水量も変動するため、前記ア
ルミニウム化合物量に廃水流量検出器による流入廃水流
量信号(Q)を乗算して、その時点の流入廃水に対する
アルミニウム化合物注入量を求め、これによってアルミ
ニウム化合物注入量の制御を行う。Since the amount of inflow wastewater also fluctuates, the amount of aluminum compound is multiplied by the amount of inflow wastewater flow signal (Q) from the wastewater flow detector to obtain the amount of aluminum compound injected into the inflow wastewater at that time. The injection amount of the aluminum compound is controlled.
【0021】このアルミニウム化合物注入量に、好まし
くは、注入結果としてのフィードバック修正用の係数
(β)を乗算して、得られる値をアルミニウム化合物注
入流量コントローラーのリモート設定値として利用し、
アルミニウム化合物注入量を制御する。This aluminum compound injection amount is preferably multiplied by a feedback correction coefficient (β) as an injection result, and the obtained value is used as a remote setting value of the aluminum compound injection flow rate controller,
Control the amount of aluminum compound injected.
【0022】また、アルミニウム化合物の過剰注入防止
のため、処理水の目標弗素濃度(f)を許容されるゼロ
では無い正の値と設定し、これと処理水弗素濃度測定値
(F’)との偏差の大きさ(F’−f)及び極性(±)
により、乗算係数(β)をフィードバック修正するのが
好ましい。In order to prevent the aluminum compound from being excessively injected, the target fluorine concentration (f) of the treated water is set to an allowable positive value other than zero, and the target fluorine concentration (f ') of the treated water is measured. (F'-f) and polarity (±)
, It is preferable that the multiplication coefficient (β) is feedback corrected.
【0023】しかしながら、前述したように、アルミニ
ウム化合物を注入された廃水は、処理水として流出して
くるまでに相当の時間遅れを要するだけでなく、この時
間遅れが流入廃水流量によっても大きく変動するため、
過去の制御時点に対応するフィードバックを確実とする
ように、通常のフィードバック制御を用いる代わりに、
前記処理水の弗素濃度検出位置までの弗素分除去装置系
統内の実効滞留容積(Qs )を求め、流入廃水量の積算
値(Q T )が該実効滞留容積(Qs )に達する毎に、乗
算係数(β)を修正する演算を行わしめることとするの
が好ましい。なお、実効滞留容積とは、前記弗素分除去
装置内における処理水(以下の実施例においては一次処
理水と二次処理水がある)の弗素濃度検出位置までの実
際に水が通過して行く部分の容積である。However, as described above, the wastewater into which the aluminum compound has been injected not only requires a considerable time delay before flowing out as treated water, but also this time delay greatly varies depending on the flow rate of the inflowing wastewater. For,
Instead of using normal feedback control to ensure feedback corresponding to past control points,
The effective retention volume (Q s ) in the fluorine removal system up to the fluorine concentration detection position of the treated water is determined, and every time the integrated value (Q T ) of the inflow wastewater reaches the effective retention volume (Q s ) , It is preferable to perform an operation for correcting the multiplication coefficient (β). Note that the effective retention volume refers to the actual passage of the treated water (the primary treated water and the secondary treated water in the following embodiments) up to the fluorine concentration detection position in the fluorine content removing device. The volume of the part.
【0024】以上を纏めると、以下の式のいづれかに従
いアルミニウム化合物注入量(Al)を演算することに
なる。なお、以下の式において、Kは装置固有の定数を
表し、γは実際に注入するアルミニウム化合物溶液の濃
度(あるいは密度)を表す。In summary, the aluminum compound injection amount (Al) is calculated according to one of the following equations. In the following formula, K represents a constant peculiar to the apparatus, and γ represents the concentration (or density) of the aluminum compound solution actually injected.
【0025】[0025]
【数1】〔詳細式〕 Al = K・〔F(x)−Al’〕・Q・β・1/γ## EQU1 ## [Detailed expression] Al = K. [F (x) -Al ']. Q..beta..1 / .gamma.
【0026】[0026]
【数2】〔簡易式〕 Al = K・〔F・α −Al’〕・Q・β・1/γ[Equation 2] [Simplified formula] Al = K · [F · α−Al ′] · Q · β · 1 / γ
【0027】[0027]
【作用】上記の様に構成された弗素分除去装置のアルミ
ニウム化合物注入量制御方法においては、脱硫廃水の発
電負荷の変動に伴う弗素濃度や含有アルミニウム濃度の
変動及び廃水流量の変動に対して実機で得られた正確な
計算式〔F(x)〕や乗算係数(α)により最適量のア
ルミニウム化合物の注入が直ちに自動的に行えるため、
負荷変動の大きな中間負荷の石炭火力発電所において
は、従来に比べて大幅なアルミニウム化合物等の薬品の
費用を節減できるようになる。According to the method for controlling the injection amount of aluminum compound in the fluorine removing apparatus having the above-described structure, the method for controlling the fluctuation of the fluorine concentration and the aluminum concentration and the fluctuation of the flow rate of the wastewater due to the fluctuation of the power generation load of the desulfurization wastewater is used. The optimum amount of the aluminum compound can be immediately and automatically injected by the accurate calculation formula [F (x)] and the multiplication coefficient (α) obtained in
In an intermediate-load coal-fired power plant having a large load variation, the cost of chemicals such as aluminum compounds can be significantly reduced as compared with the related art.
【0028】また、炭種の変動や炭種のブレンド比の変
更に伴う廃水の成分構成比の変動に対しても処理水の弗
素濃度によるアルミニウム化合物注入量補正機構による
制御を有効に作用させることも可能なので、従来の様に
処理水質を安全側に確保するためにアルミニウム化合物
を過剰に注入する必要が無くなるのみならず、発電負荷
の変動に合わせて運転員がアルミニウム化合物注入量の
設定変更をその都度行う必要も無くなった。Further, the control by the aluminum compound injection amount correction mechanism based on the fluorine concentration of the treated water effectively acts on the fluctuation of the composition ratio of the wastewater due to the fluctuation of the coal type and the change of the blend ratio of the coal type. Not only eliminates the need to inject excessive amounts of aluminum compound to ensure the treated water quality on the safe side as in the past, but also allows the operator to change the setting of the amount of injected aluminum compound according to fluctuations in the power generation load. You don't have to do it each time.
【0029】[0029]
【実施例】以下、図面を参照しつつ、本発明を実施例で
更に詳細に説明するが、本発明は実施例に限定されるも
のでは無い。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail by way of embodiments with reference to the drawings, but the present invention is not limited to the embodiments.
【0030】図1は、本発明に使用する弗素分除去装置
である廃水処理装置の一例における各処理工程と信号系
統を示すフローチャートである。FIG. 1 is a flowchart showing each processing step and a signal system in an example of a wastewater treatment apparatus which is a fluorine removal apparatus used in the present invention.
【0031】この装置は、脱硫廃水処理用装置であり、
図1において一次処理水16が流出する位置より左側は
一次処理装置であり、右側は二次処理装置(軟化装置)
である。This device is a desulfurization wastewater treatment device,
In FIG. 1, the left side from the position where the primary treatment water 16 flows out is a primary treatment unit, and the right side is a secondary treatment unit (softening unit).
It is.
【0032】この一次処理装置は、反応槽6(アルミニ
ウム化合物を注入)、第一凝集槽7(例えば、アニオン
系高分子凝集剤を助剤として使用)、第一沈澱槽15を
有し、更に附帯設備として、アルミニウム化合物貯槽1
2、アルミニウム化合物注入ポンプ13、アルミニウム
化合物注入コントロール弁9、pH調整剤注入バルブ1
8(例えば、苛性ソーダを注入)、pH調整剤貯槽(図
示されていない)を備えている。第一沈澱槽15には、
汚泥引抜きポンプ17が備えられている。反応槽6は、
上記pH調整剤注入バルブ18によるpH調整機能を有
し(pH値を約6〜約8に調整)、pH検出器19が備
えられている。This primary treatment apparatus has a reaction tank 6 (injecting an aluminum compound), a first flocculation tank 7 (for example, using an anionic polymer flocculant as an auxiliary), and a first precipitation tank 15. Aluminum compound storage tank 1 as ancillary equipment
2, aluminum compound injection pump 13, aluminum compound injection control valve 9, pH adjuster injection valve 1
8 (for example, caustic soda is injected), and a pH adjusting agent storage tank (not shown). In the first settling tank 15,
A sludge extraction pump 17 is provided. Reaction tank 6
It has a pH adjusting function by the pH adjusting agent injection valve 18 (adjusts the pH value to about 6 to about 8), and is provided with a pH detector 19.
【0033】二次処理装置は、軟化槽31(例えば、炭
酸ソーダ、苛性ソーダを注入)、第二凝集槽32(例え
ば、アニオン系高分子凝集剤を助剤として使用)、第二
沈澱槽33を有する。軟化槽31には、pH検出器36
が備えられ、第二沈澱槽33には、汚泥引抜きポンプ3
5が備えられている。The secondary treatment apparatus includes a softening tank 31 (for example, injecting sodium carbonate and caustic soda), a second flocculation tank 32 (for example, using an anionic polymer flocculant as an auxiliary), and a second precipitation tank 33. Have. In the softening tank 31, a pH detector 36 is provided.
The second settling tank 33 is provided with a sludge pulling pump 3
5 are provided.
【0034】脱硫廃水には一般にマグネシウム分(マグ
ネシウムイオン)が含まれており、例えば、軟化槽31
に炭酸ソーダに加えると共に苛性ソーダを注入してpH
が10を越えるように(例えば、約10.5)pH調整
すると、水酸化マグネシウムの沈澱が生成するが、恐ら
くこれに吸着される形で一次処理水に残存する弗素分の
かなりの部分が同時に沈澱し、従って、二次処理水中の
弗素濃度は更に低くなる。The desulfurization wastewater generally contains a magnesium component (magnesium ion).
To sodium carbonate and inject caustic soda to pH
If the pH is adjusted to exceed 10 (eg, about 10.5), a precipitate of magnesium hydroxide will form, but a significant portion of the fluorine remaining in the primary effluent will probably be absorbed at the same time. It precipitates and therefore the fluorine concentration in the secondary treatment water is even lower.
【0035】上記の弗素分除去装置において、流入廃水
2の弗素イオン濃度を連続的又は短時間の間隔で測定す
る廃水弗素濃度自動分析計3(例えば、イオン電極法を
利用、特開平3−51754号公報参照)により廃水の
弗素濃度Fを測定し、このFの信号を演算手段としての
例えばコンピューター100に入力し、必要な全アルミ
ニウム量を下記の式に従いコンピューターのCPUで計
算する。In the above-mentioned fluorine removing apparatus, an automatic analyzer 3 for measuring the fluorine ion concentration of the inflowing wastewater 2 continuously or at short intervals (for example, utilizing the ion electrode method, Japanese Patent Laid-Open No. 3-51754). The fluorine concentration F of the wastewater is measured according to the above-mentioned method, and a signal of this F is input to, for example, a computer 100 as arithmetic means, and the necessary total aluminum amount is calculated by the CPU of the computer according to the following equation.
【0036】[0036]
【数3】F(x)=a・logF2 +b・logF+C 〔但し、a、b、Cは定数〕F (x) = a · logF 2 + b · logF + C [where a, b and C are constants]
【0037】しかし、この演算が複雑なため、下記の係
数αを使うのが便利である。係数αは、実機及び各種フ
ィールドテストの結果より求めるもので、簡便に使用で
き、F×αとして、必要な全アルミニウム量を求めるこ
とができる。なお、αはコンピューター100のメモリ
ー部に格納されており、その値は1.7ないし4.0の
範囲に存在する。However, since this calculation is complicated, it is convenient to use the following coefficient α. The coefficient α is obtained from the results of actual equipment and various field tests, and can be easily used. The required total aluminum amount can be obtained as F × α. Note that α is stored in the memory unit of the computer 100, and its value is in the range of 1.7 to 4.0.
【0038】流入廃水2の含有アルミニウムイオン濃度
を連続的又は短時間の間隔で測定する廃水アルミニウム
濃度自動分析計4により含有アルミニウム濃度Al’を
測定し、このAl’の信号をコンピューター100に入
力し、CPUで〔(F(x)−Al’〕又は〔F・α−
Al’〕の減算を行い、注入により増加すべきアルミニ
ウム濃度を算出する。The aluminum concentration Al ′ is measured by a wastewater aluminum concentration automatic analyzer 4 for continuously or at short time intervals measuring the aluminum ion concentration of the inflowing wastewater 2, and a signal of this Al ′ is input to the computer 100. And [(F (x) -Al ′] or [F · α-
Al ′] is calculated, and the aluminum concentration to be increased by the implantation is calculated.
【0039】この値に流入廃水2の流量を検出する流量
検出器1よりの瞬時流量信号QをCPUで乗算し、更に
本装置に使用されている分析機器や測定機器等の各種機
器類の測定レンジ、制御レンジ及び使用単位によって決
まる装置固有の定数K(メモリー部に格納されている)
を乗算して、アルミニウム化合物濃度100%とした場
合の瞬時のアルミニウム化合物注入量が算出される。This value is multiplied by the CPU by an instantaneous flow rate signal Q from the flow rate detector 1 for detecting the flow rate of the inflow wastewater 2, and furthermore, measurement of various instruments such as analytical instruments and measuring instruments used in the apparatus. Device-specific constant K determined by range, control range and unit of use (stored in memory)
And the instantaneous aluminum compound injection amount when the aluminum compound concentration is 100% is calculated.
【0040】更に、実際のアルミニウム化合物溶液濃度
を測定するアルミニウム化合物濃度検出器11の濃度信
号γをコンピューター100に入力し、CPUで上記の
アルミニウム化合物濃度100%とした場合の瞬時のア
ルミニウム化合物注入量に1/γを乗算することにより
実液濃度におけるアルミニウム化合物注入流量が算出さ
れる。Further, the concentration signal γ of the aluminum compound concentration detector 11 for measuring the actual aluminum compound solution concentration is input to the computer 100, and the instantaneous aluminum compound injection amount when the above-mentioned aluminum compound concentration is set to 100% by the CPU. Is multiplied by 1 / γ to calculate the aluminum compound injection flow rate at the actual solution concentration.
【0041】なお、アルミニウム化合物濃度が常時一定
の溶液が用意される場合は、1/γを演算器の内部定数
に含めて取扱い、アルミニウム化合物濃度検出器11を
省略することもできる。When a solution having a constant aluminum compound concentration is prepared, 1 / γ is included in the internal constant of the arithmetic unit, and the aluminum compound concentration detector 11 can be omitted.
【0042】次に、上記「数1」又は「数2」の式にお
ける注入量補正乗算係数βを使用する好ましい態様の場
合については、例えば、図2のプログラム処理手順を示
すフローチャートで説明されている。Next, a preferred embodiment using the injection amount correction multiplication coefficient β in the above equation (1) or (2) will be described, for example, with reference to the flowchart of FIG. I have.
【0043】βは、下記の式で表される。Β is expressed by the following equation.
【0044】[0044]
【数4】β=1+RV(tn-1)+ΔRV(tn) 〔但し、ΔRV(tn)=k(F’−f)(tn)である。〕## EQU4 ## β = 1 + RV (tn-1) +. DELTA.RV (tn) [where, .DELTA.RV (tn) = k (F'-f) (tn) . ]
【0045】この式で、一次処理水16の弗素イオン濃
度を測定する一次処理水弗素濃度分析計14からの弗素
濃度信号F’と一次処理水16の弗素濃度目標値fとの
偏差(F’−f)による今回の補正値が、ΔRV(tn)=
k(F’−f)(tn)である。kは、1回毎の補正値に対
する比例係数である。前回までの補正値の累積値が、R
V(tn-1)である。In this equation, the deviation (F ') between the fluorine concentration signal F' from the primary treatment water fluorine concentration analyzer 14 for measuring the fluorine ion concentration of the primary treatment water 16 and the fluorine concentration target value f of the primary treatment water 16 is obtained. −f) is ΔRV (tn) =
k (F'-f) (tn) . k is a proportional coefficient for each correction value. The cumulative value of the correction values up to the previous time is R
V (tn-1) .
【0046】「数1」や「数2」の式が常時演算される
のに対し、「数4」の式は流入廃水量の積算値QT が実
効滞留容積QS (この場合、図1の弗素分除去装置にお
いて弗素濃度分析計14の位置までの実効滞留容積であ
る)に達する毎に演算される。即ち、QT ≧QS となっ
た時に係数βが新しい値に修正され、次回まで固定され
る。また、同時に流入廃水量積算値QT もゼロにリセッ
トされ、積算を再開する。In contrast to the equations (1) and (2) which are always calculated, the equation (4) is based on the fact that the integrated value Q T of the inflowing wastewater amount is the effective accumulated volume Q S (in this case, FIG. Is calculated every time the amount reaches the position of the fluorine concentration analyzer 14). In other words, the coefficient β is modified to a new value when it becomes a Q T ≧ Q S, is fixed until the next time. Further, the reset to zero inflow wastewater amount integrated value Q T at the same time, restarts the integration.
【0047】次に、図2のフローチャートに従って、コ
ンピューター100で行われるプログラム処理手順を説
明する。ある時点で、装置運転中と検知されると〔ステ
ップ(1)〕、次に前回のサイクルまでの流入廃水量の
積算回路による積算値が処理水の弗素濃度検出位置まで
の弗素分除去装置の実効滞留容積の値に達したか否かを
比較回路で判断し〔ステップ(2)〕、まだ達していな
ければ前回のサイクルと同じ記憶β値を用い、「数2」
(「数1」でもよい)の式の演算を演算回路で行い〔ス
テップ(3)〕、この結果に基づいてアルミニウム化合
物が反応槽6に注入される。次に今回の流入廃水流量を
前回までの同積算値に加算する〔ステップ(4)〕。Next, a program processing procedure performed by the computer 100 will be described with reference to the flowchart of FIG. At some point, when it is detected that the apparatus is in operation [Step (1)], the integrated value of the inflowing wastewater amount up to the previous cycle by the integrating circuit is used by the fluorine removing apparatus to reach the fluorine concentration detecting position of the treated water. The comparison circuit determines whether or not the value of the effective retention volume has been reached [step (2)]. If the value has not yet reached, the same stored β value as in the previous cycle is used, and "expression 2"
The operation of the formula (Equation 1) is performed by an arithmetic circuit [Step (3)], and an aluminum compound is injected into the reaction tank 6 based on the result. Next, the current inflow wastewater flow rate is added to the same integrated value up to the previous time (step (4)).
【0048】かかるサイクルを繰り返し、ステップ
(2)でQT ≧QS の条件を満足することとなったら、
「数4」の式の演算を演算回路で行い〔ステップ
(5)〕、新しい注入量補正乗算係数βを求め、これを
次回サイクルからのステップ(3)の演算に用いる。こ
の場合、流入廃水流量の前記積算回路の積算値をゼロに
リセットする〔ステップ(6)〕。そこから、新たな
「β」を用いてステップ(2)→ステップ(3)→ステ
ップ(4)のサイクルを繰り返し、再度QT ≧QS の条
件を満足したらステップ(5)→ステップ(6)と進
む。かかる処理手順が繰り返される訳である。[0048] repeat such a cycle, if it decided to satisfy the conditions of Q T ≧ Q S in step (2),
The calculation of Expression 4 is performed by a calculation circuit [Step (5)], and a new injection amount correction multiplication coefficient β is obtained, and this is used for the calculation of Step (3) from the next cycle. In this case, the integrated value of the inflow wastewater flow rate in the integrating circuit is reset to zero [step (6)]. From there, step by using the new "β" (2) → step (3) → step repeating the cycle of (4), If you are satisfied with the conditions of re-Q T ≧ Q S step (5) → step (6) And proceed. That is, the processing procedure is repeated.
【0049】上述の場合には、注入量乗算係数βを求め
るための弗素濃度の測定を一次処理水16を用いて行う
フィードバック制御であるが、代わりに二次処理水37
を用いて二次処理水弗素濃度分析計34により処理水の
弗素イオン濃度を測定して、これをF’としてフィード
バックしても全く同様に制御することができる。後者の
場合、実効滞留容積QS は、図1の弗素分除去装置にお
ける二次処理水弗素濃度分析計34の位置までの実効滞
留容積である。In the above case, the feedback control is performed using the primary treatment water 16 to measure the fluorine concentration for obtaining the injection amount multiplication coefficient β.
Can be controlled in exactly the same way by measuring the fluoride ion concentration of the treated water with the secondary treated water fluorine concentration analyzer 34 and feeding it back as F '. In the latter case, the effective residence volume Q S is the effective retention volume to the position of the secondary treated water fluorine concentration analyzer 34 in the fluorine content removing device of FIG.
【0050】また、一次処理水弗素濃度分析計14と二
次処理水弗素濃度分析計34の両方を設けてもよい。こ
の場合、例えば、流入廃水流量や流入廃水の弗素イオン
濃度の単位時間当りの変動が或る値を越えた時は一次処
理水弗素濃度分析計14による一次処理水弗素イオン濃
度信号を注入量乗算係数βを求めるために用い、それ以
外の時は二次処理水弗素濃度分析計34による二次処理
水弗素イオン濃度信号を注入量乗算係数βを求めるため
に用いるようにしてもよい。こうすれば、前者の場合は
後者の場合に比して実効滞留容積が小さいので、流入廃
水流量や流入廃水弗素イオン濃度の急激な変動に対して
より短時間で対応できるという利点が有り、一方、流入
廃水流量や流入廃水弗素イオン濃度の変動がそれ程大き
くない時は、所望の処理水質により密接に関係する二次
処理水弗素イオン濃度信号でより精密にフィードバック
制御できるという利点も確保できる。また、この目的の
ために処理水弗素濃度分析計を共用とし、サンプルライ
ンを交互に切り換え可能とし、一次処理水弗素イオン濃
度も二次処理水弗素イオン濃度も一つの処理水弗素濃度
分析計で測定できるようにしてもよい。Further, both the primary treatment water fluorine concentration analyzer 14 and the secondary treatment water fluorine concentration analyzer 34 may be provided. In this case, for example, when the variation per unit time of the inflow wastewater flow rate and the influent wastewater fluoride ion concentration exceeds a certain value, the primary treatment water fluorine concentration signal from the primary treatment water fluorine concentration analyzer 14 is multiplied by the injection amount. The coefficient β may be used to determine the coefficient β, and in other cases, the secondary treatment water fluoride ion concentration signal from the secondary treatment water fluorine concentration analyzer 34 may be used to determine the injection amount multiplication coefficient β. In this case, since the former case has a smaller effective retention volume than the latter case, there is an advantage that it is possible to respond to a rapid change in the inflow wastewater flow rate or the influent wastewater fluoride ion concentration in a shorter time. In addition, when the fluctuation of the inflow wastewater flow rate and the inflow wastewater fluoride ion concentration is not so large, the advantage that the feedback control can be performed more precisely by the secondary treatment water fluoride ion concentration signal which is more closely related to the desired treatment water quality can be secured. Also, for this purpose, the treated water fluorine concentration analyzer is shared, and the sample line can be switched alternately, so that the primary treated water fluoride ion concentration and the secondary treated water fluoride ion concentration can be one treated water fluoride concentration analyzer. The measurement may be performed.
【0051】処理水弗素濃度目標値fをゼロではない排
水許容限度内の正の値に設定するとは、具体的には、弗
素濃度分析計14又は34の測定限界値(下限)より高
く、測定誤差値より大きな値で且つ排出許容限度内の値
に設定することを意味し、これはアルミニウム化合物の
過剰注入を避ける制御を行うためである。なぜならば、
弗素濃度分析計14又は34の測定限界値+測定誤差値
の値以下にf値を設定すると、過剰注入によってF’が
弗素濃度分析計14又は34の測定限界値+測定誤差値
の値以下になった時には、過剰注入かどうか、その過剰
注入度合いも判別できなくなるからである。To set the treated water fluorine concentration target value f to a positive value within the allowable limit of drainage which is not zero, specifically, is set higher than the measurement limit value (lower limit) of the fluorine concentration analyzer 14 or 34, This means setting the value to a value larger than the error value and within the allowable discharge limit, in order to perform control to avoid excessive injection of the aluminum compound. because,
If the f value is set to be equal to or less than the measurement limit value of the fluorine concentration analyzer 14 or 34 plus the measurement error value, the excess injection will cause F ′ to fall below the measurement limit value of the fluorine concentration analyzer 14 or 34 plus the measurement error value. This is because, when this happens, it becomes impossible to determine whether the injection is excessive or not, and the degree of excessive injection.
【0052】この様にして求められた「数1」又は「数
2」の式によるアルミニウム化合物注入量Alは、アル
ミニウム化合物注入流量コントローラー10のリモート
設定値として設定され、アルミニウム化合物注入流量検
出器8により実測された注入量とコンピューター100
で比較調整され、注入量コントロール弁9への開度指令
MV値(操作出力値、manipulating value)として出力
される。なお、注入量を制御する駆動部のコントロール
弁9については、必ずしもコントロール弁でなくても良
く、例えば、コントロール弁を無くしてアルミニウム化
合物注入ポンプ13としてプランジャー型定量ポンプを
使用し、このプランジャー型定量ポンプにストローク制
御や回転数制御を組み合わせたものでも良い。The aluminum compound injection amount Al obtained by the equation (1) or (2) thus obtained is set as a remote set value of the aluminum compound injection flow rate controller 10 and the aluminum compound injection flow rate detector 8 Injection amount measured by computer and computer 100
And output as an opening command MV value (operation output value, manipulating value) to the injection amount control valve 9. The control valve 9 of the drive unit for controlling the injection amount is not necessarily a control valve. For example, a plunger type metering pump may be used as the aluminum compound injection pump 13 without the control valve. A combination of stroke control and rotation speed control with the type metering pump may be used.
【0053】図3は、一例として、脱硫廃水中の弗素濃
度とアルミニウム濃度、第二沈澱槽から得られる二次処
理水の弗素濃度(「フィードバック無」の場合と二次処
理水の弗素濃度による「フィードバック有」の場合)の
経時変動を表すグラフ図である。この図3において、横
軸は運転日数を表し、縦軸は濃度を表す。このグラフ
は、セミロググラフで、縦軸の濃度目盛は対数目盛であ
る。FIG. 3 shows, by way of example, the fluorine concentration and the aluminum concentration in the desulfurization wastewater, the fluorine concentration of the secondary treatment water obtained from the second precipitation tank (in the case of “no feedback” and the fluorine concentration of the secondary treatment water). FIG. 9 is a graph illustrating the temporal variation of “with feedback”). In FIG. 3, the horizontal axis represents the number of operating days, and the vertical axis represents the concentration. This graph is a semi-log graph, and the density scale on the vertical axis is a logarithmic scale.
【0054】図3において、曲線(a)は廃水のアルミ
ニウム濃度であり、曲線(b)は廃水の弗素濃度であ
り、曲線(c)は「フィードバック無」の場合の二次処
理水の弗素濃度であり、曲線(d)は「フィードバック
有」の場合の二次処理水の弗素濃度である。In FIG. 3, curve (a) shows the aluminum concentration of the wastewater, curve (b) shows the fluorine concentration of the wastewater, and curve (c) shows the fluorine concentration of the secondary treated water in the case of "no feedback". And curve (d) represents the fluorine concentration of the secondary treated water in the case of “with feedback”.
【0055】「フィードバック有」の制御を行った方
が、「フィードバック無」の場合と比べて、二次処理水
の弗素濃度の変動巾が小さくなり、好ましいことが分か
る。It can be seen that the control with "feedback" is preferable because the fluctuation range of the fluorine concentration of the secondary treatment water is smaller than the control without "feedback".
【0056】なお、本発明における「数1」又は「数
2」の式の演算は、専用の演算器の他に、制御用コンピ
ューターでも、市販品で上記演算が可能なワンループ・
コントローラーでも、パソコンやシーケンサーの演算回
路でも使用できる。In the present invention, the arithmetic operation of the expression (Equation 1) or (Equation 2) can be performed not only by a dedicated operation unit but also by a control computer using a commercially available one-loop operation which can perform the above operation.
It can be used as a controller, or as an arithmetic circuit for a personal computer or sequencer.
【0057】[0057]
【発明の効果】以上説明してきたように、本発明によれ
ば、弗素含有廃水の性状変動、廃水流量変動に対して、
ほぼリアルタイムでアルミニウム化合物の適正量の注入
ができ、更に、必要に応じて微妙な補正修正機構により
アルミニウム化合物の過剰注入の防止ができるため、特
に負荷変動の大きな中間負荷石炭火力発電所の脱硫廃水
では、アルミニウム化合物やその他の薬品の使用量が大
幅に低減可能となる。As described above, according to the present invention, fluctuations in the properties of the fluorine-containing wastewater and fluctuations in the flow rate of the wastewater can be prevented.
It is possible to inject an appropriate amount of aluminum compound in near real time and, if necessary, to prevent excessive injection of aluminum compound with a delicate correction and correction mechanism. Thus, the amount of use of the aluminum compound and other chemicals can be significantly reduced.
【0058】流入廃水の流量・性状等の変動に対する自
動追従が従来に比較して格段に改善されるため、運転員
の負担も軽減される。Automatic follow-up to fluctuations in the flow rate and properties of the inflow wastewater is remarkably improved as compared with the related art, so that the burden on the operator is reduced.
【図1】本発明に使用する弗素分除去装置を含む廃水処
理装置の一例における各処理工程と信号系統を示すフロ
ーチャートである。FIG. 1 is a flowchart showing each processing step and a signal system in an example of a wastewater treatment apparatus including a fluorine content removing apparatus used in the present invention.
【図2】注入量補正乗算係数βによる制御系のプログラ
ム処理手順を示すフローチャートである。FIG. 2 is a flowchart showing a program processing procedure of a control system based on an injection amount correction multiplication coefficient β.
【図3】本発明の制御方法に従った場合の廃水処理効果
を説明する図で、脱硫廃水中の弗素濃度とアルミニウム
濃度、第二沈澱槽から得られる二次処理水の弗素濃度
(フィードバック無の場合とフィードバック有の場合)
の経時変動を表すグラフ図である。FIG. 3 is a diagram for explaining the wastewater treatment effect when the control method according to the present invention is used, and shows the fluorine concentration and aluminum concentration in the desulfurization wastewater, and the fluorine concentration of the secondary treatment water obtained from the second precipitation tank (without feedback). With and with feedback)
FIG. 5 is a graph showing the time-dependent fluctuation of.
【図4】石炭火力発電所の運転時間の経過に伴う脱硫廃
水の弗素濃度の変化をモデル的に表したグラフ図であ
る。FIG. 4 is a graph schematically showing a change in the fluorine concentration of the desulfurization wastewater with the elapse of the operation time of the coal-fired power plant.
1 廃水流量検出器 2 流入廃水 3 廃水弗素濃度分析計 4 廃水アルミニウム濃度分析計 6 反応槽 7 第一凝集槽 8 アルミニウム化合物流量検出器 9 アルミニウム化合物注入コントロール弁 10 アルミニウム化合物注入コントローラー 11 アルミニウム化合物濃度検出器 12 アルミニウム化合物貯槽 13 アルミニウム化合物注入ポンプ 14 一次処理水弗素濃度分析計 15 第一沈澱槽 16 一次処理水 17 汚泥引抜きポンプ 18 pH調整剤注入バルブ 19 pH検出器 31 軟化槽 32 第二凝集槽 33 第二沈澱槽 34 二次処理水弗素濃度分析計 35 汚泥引抜きポンプ 36 pH検出器 37 二次処理水 100 コンピューター REFERENCE SIGNS LIST 1 Wastewater flow detector 2 Inflow wastewater 3 Wastewater fluorine concentration analyzer 4 Wastewater aluminum concentration analyzer 6 Reaction tank 7 First coagulation tank 8 Aluminum compound flow detector 9 Aluminum compound injection control valve 10 Aluminum compound injection controller 11 Aluminum compound concentration detection 12 Aluminum compound storage tank 13 Aluminum compound injection pump 14 Primary treatment water fluorine concentration analyzer 15 First precipitation tank 16 Primary treatment water 17 Sludge extraction pump 18 pH adjusting agent injection valve 19 pH detector 31 Softening tank 32 Second flocculation tank 33 Second precipitation tank 34 Secondary treatment water fluorine concentration analyzer 35 Sludge extraction pump 36 pH detector 37 Secondary treatment water 100 Computer
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鳥屋尾 守 愛知県名古屋市緑区大高町字北関山20番 地の1 中部電力株式会社 電力技術研 究所内 (72)発明者 ▲浅▼野 宗光 愛知県名古屋市緑区大高町字北関山20番 地の1 中部電力株式会社 電力技術研 究所内 (72)発明者 高田 ▲とき▼男 東京都文京区本郷5丁目5番16号 オル ガノ株式会社内 (72)発明者 高見 英俊 東京都文京区本郷5丁目5番16号 オル ガノ株式会社内 (56)参考文献 特開 昭60−202789(JP,A) 特開 昭60−197293(JP,A) 特開 昭58−143878(JP,A) 実開 昭52−24762(JP,U) (58)調査した分野(Int.Cl.7,DB名) C02F 1/00 - 1/78 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mamoru Torio 1 at Kita-Kanzan, 20-chome, Odaka-cho, Midori-ku, Nagoya-shi, Aichi Power Equipment Research Institute, Chubu Electric Power Co., Inc. (72) Inventor (72) Inventor Takada ▲ Toki ▼ Male 5-5-1, Hongo, Bunkyo-ku, Tokyo Organo Stocks, 20-1, Kita-Sekiyama, Odaka-cho, Midori-ku, Nagoya-shi, Aichi, Japan In-company (72) Inventor Hidetoshi Takami 5-5-16-1 Hongo, Bunkyo-ku, Tokyo Organo Co., Ltd. (56) References JP-A-60-202789 (JP, A) JP-A-60-197293 (JP, A) Japanese Patent Application Laid-Open No. Sho 58-1443878 (JP, A) Japanese Utility Model Application Sho 52-24762 (JP, U) (58) Fields investigated (Int. Cl. 7 , DB name) C02F 1/00-1/78
Claims (3)
検出器、流入廃水の弗素濃度を検出する廃水弗素濃度分
析計、及び流入廃水のアルミニウム濃度を検出する廃水
アルミニウム濃度分析計を備えた弗素及びアルミニウム
含有廃水から弗素分を除去する弗素分除去装置の制御方
法において、前記廃水弗素濃度分析計からの弗素濃度信
号により、弗素分除去に必要なアルミニウム濃度を予め
定めた計算式又は乗算係数により算出し、この算出必要
アルミニウム濃度から前記廃水アルミニウム濃度分析計
からのアルミニウム濃度信号を減算し、更に前記廃水流
量検出器からの流入廃水流量信号を乗算する演算回路に
よりアルミニウム化合物注入量を演算出力する弗素及び
アルミニウム含有廃水処理におけるアルミニウム化合物
注入量の制御方法。1. A wastewater flow rate detector for detecting a flow rate of an inflowing wastewater, a wastewater fluorine concentration analyzer for detecting a fluorine concentration of the inflowing wastewater, and a wastewater aluminum concentration analyzer for detecting an aluminum concentration of the inflowing wastewater. And a control method of a fluorine removing device for removing fluorine from aluminum-containing wastewater, wherein a fluorine concentration signal from the wastewater fluorine concentration analyzer is used to determine an aluminum concentration required for fluorine removal by a predetermined calculation formula or a multiplication coefficient. Calculate and subtract the aluminum concentration signal from the wastewater aluminum concentration analyzer from the calculated required aluminum concentration, and further calculate and output the aluminum compound injection amount by an arithmetic circuit that multiplies the inflow wastewater flow signal from the wastewater flow detector. A method for controlling the amount of aluminum compound injected in treating wastewater containing fluorine and aluminum.
排水許容限度内の正の値に設定し、該目標弗素濃度値と
処理水の弗素濃度測定値との偏差の極性及びその大きさ
により前記アルミニウム化合物注入量の演算出力を補正
する為の補正乗算係数を算出する演算回路を設け、流入
廃水流量を積算する積算回路による積算値が前記処理水
の弗素濃度検出位置までの前記弗素分除去装置の実効滞
留容積値に達したと比較回路が判断する毎に、前記補正
乗算係数を演算・修正すると共に前記積算値をリセット
する機能を前記弗素分除去装置が備え、前記アルミニウ
ム化合物注入量に前記補正乗算係数を乗算した値をアル
ミニウム化合物注入量コントローラーのリモート設定値
としてアルミニウム化合物注入量を制御することを特徴
とする請求項1に記載の弗素及びアルミニウム含有廃水
処理におけるアルミニウム化合物注入量の制御方法。2. The target fluorine concentration value of the treated water is set to a positive value within the allowable limit of drainage which is not zero, and the polarity and magnitude of the deviation between the target fluorine concentration value and the measured fluorine concentration value of the treated water are set. And a calculation circuit for calculating a correction multiplication coefficient for correcting the calculation output of the aluminum compound injection amount, wherein the integrated value obtained by the integration circuit for integrating the inflow wastewater flow rate is such that the fluorine content up to the fluorine concentration detection position of the treated water is obtained. Each time the comparison circuit determines that the effective retention volume value of the removing device has been reached, the fluorine component removing device is provided with a function of calculating and correcting the correction multiplication coefficient and resetting the integrated value. The aluminum compound injection amount is controlled by using a value obtained by multiplying the aluminum compound injection amount by the correction multiplication coefficient as a remote setting value of an aluminum compound injection amount controller. Of controlling the amount of aluminum compound injected in the treatment of wastewater containing fluorine and aluminum described above.
有する一次処理装置及び二次処理装置を包含する弗素分
除去装置であって、前記反応槽の上流に流入廃水流量検
出器並びに廃水弗素濃度分析計及び廃水アルミニウム濃
度分析計を備え、前記一次処理装置と前記二次処理装置
の間か前記二次処理装置の下流かあるいは双方に処理水
弗素濃度分析計を所要に応じて備えており、請求項1又
は2のいづれかに記載のアルミニウム化合物注入量の制
御方法を行うための演算手段を備え、更に、前記演算手
段による演算結果に応じてアルミニウム化合物を前記反
応槽に注入するためのアルミニウム化合物注入手段を備
えていることを特徴とする弗素分除去装置。3. A fluorine removal device including a primary treatment device and a secondary treatment device having a reaction tank for injecting an aluminum compound, wherein a flow rate detector of an inflowing wastewater and a fluorine concentration analyzer of a wastewater upstream of the reaction tank. And a wastewater aluminum concentration analyzer, wherein a treated water fluorine concentration analyzer is provided as necessary between the primary treatment device and the secondary treatment device, downstream of the secondary treatment device, or both. An arithmetic means for performing the method of controlling the injection amount of aluminum compound according to any one of 1 and 2, further comprising an aluminum compound injection means for injecting an aluminum compound into the reaction tank in accordance with a calculation result by the arithmetic means. A fluorine component removing device, comprising:
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3331522A JP3053482B2 (en) | 1991-11-21 | 1991-11-21 | Method for controlling injection amount of aluminum compound in treatment of wastewater containing fluorine and aluminum and fluorine removing device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3331522A JP3053482B2 (en) | 1991-11-21 | 1991-11-21 | Method for controlling injection amount of aluminum compound in treatment of wastewater containing fluorine and aluminum and fluorine removing device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0615279A JPH0615279A (en) | 1994-01-25 |
JP3053482B2 true JP3053482B2 (en) | 2000-06-19 |
Family
ID=18244596
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JP3331522A Expired - Fee Related JP3053482B2 (en) | 1991-11-21 | 1991-11-21 | Method for controlling injection amount of aluminum compound in treatment of wastewater containing fluorine and aluminum and fluorine removing device |
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JP (1) | JP3053482B2 (en) |
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JP4765373B2 (en) * | 2005-03-31 | 2011-09-07 | 栗田工業株式会社 | Method and apparatus for treating fluorine-containing wastewater |
JP6982759B2 (en) * | 2018-02-13 | 2021-12-17 | 三菱重工パワー環境ソリューション株式会社 | Water treatment system |
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1991
- 1991-11-21 JP JP3331522A patent/JP3053482B2/en not_active Expired - Fee Related
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