【０００１】
【発明の属する技術分野】
本発明は、発電プラント、化学プラント等の起動運転時、復水系統、給水系統に流れる復水・給水および各種プラントにおいて流通する流体に含まれる懸濁固形物を効果的に除去するろ過装置およびその運転方法に関する。
【０００２】
【従来の技術】
各種プラントにおいて流通する流体において懸濁固形物を除去する方法について、以下に発電プラントを参照して説明する。火力発電プラントや原子力発電プラント等の発電プラントでは、起動運転時、復水・給水中に含まれる、例えば酸化鉄等の懸濁固形物を除去するろ過装置として復水・給水処理装置が設けられている。
【０００３】
この復水・給水処理装置は、例えばポリエチレン等の高分子材で作製された中空糸膜フィルタをモジュールとし、このモジュールをろ過器内に収容し、処理水を中空糸膜フィルタの外側から内側に流し、膜表面で懸濁物質を除去するようになっている。そして、モジュールにした中空糸膜フィルタは、運転中の水質、例えば導電率、ろ過器の入口、出口の圧力差、処理水の収量等が予め定められた量を超えたとき交換するようになっている。
【０００４】
ところで、起動運転時、処理水は、温度が低く、粘性も比較的高い。このため、中空糸膜は、処理水の流れの抵抗が大きくなり、その定格流量をろ過することができなくなり、場合によっては目詰まりを起す可能性もあった。
【０００５】
目詰まりの防止手段には、中空糸膜を収容するろ過器の入口側と出口側とを互いに連絡させるバイパスラインを設け、バイパスラインに設けた弁を起動運転時、全開しておき、徐々に弁開度を絞って定格流量になると弁を全閉にする運転方法が、例えば特開平１１−４２４２４号公報（特許文献１参照）に開示されている。
【０００６】
【特許文献１】
特開平１１−４２４２４号公報
【０００７】
【発明が解決しようとする課題】
特開平１１−４２４２４号公報は、ろ過器の入口側と出口側とを結ぶバイパスラインに弁を備え、この弁を全開から徐々に絞り、処理水を急激に中空糸膜フィルタに流さないようにしているので、中空糸膜に与えられる流量抵抗を少なくさせている点で優れているものの、それでも幾つかの課題点を抱えており、その一つに圧力変動の対処手段がある。
【０００８】
復水・給水処理装置は、運転開始の初期時から高温・高圧の処理水をバイパスラインに流すことがある。高温・高圧の処理水がバイパスラインに流れると、弁の開度を徐々に絞っていく関係上、圧力変動が起り、処理水はフラッシュ（沸騰）する。処理水がフラッシュすると、バイパスラインは、もはやそれを抑制することができず、遂にはその影響が中空糸膜フィルタにも伝わり、中空糸膜フィルタは圧力変動に基づく圧力差（押圧力）によって座屈し、本来の処理能力を著しく低下させることがあった。
【０００９】
また、定格運転に入る前の昇温過程時、処理水はその粘性が低下し、透水性能が増加する。このため、中空糸膜フィルタは、軟化し、圧力変動に伴う圧力差に抗しきれず、座屈し、処理水の定格量を充分に処理できない等の問題があった。
【００１０】
本発明は、このような事情に基づいてなされたもので、ろ過器内に収容する中空糸膜フィルタの入口側と出口側との圧力差が常時一定値になるように維持させ、また、処理水の温度上昇率が常時一定値になるように弁の開度を自動制御し、中空糸膜フィルタを安定運転させるろ過装置およびその運転方法を提供することを目的とする。
【００１１】
【課題を解決するための手段】
本発明に係るろ過装置は、上述の目的を達成するために、請求項１に記載したように、プラントに設けられ中空糸膜フィルタを収容するろ過器と、このろ過器の入口および出口に設けられた入口弁と出口弁と、前記ろ過器の入口圧力とその出口圧力との圧力差が予め定められた圧力以下になるように前記入口弁および出口弁を開閉させる弁開閉信号を演算する制御装置とを備えたものである。
【００１２】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項２に記載したように、プラントに設けられ中空糸膜フィルタを収容するろ過器と、このろ過器の入口および出口に設けられた入口弁と出口弁と、前記ろ過器の入口圧力とその出口圧力との圧力差が予め定められた圧力以下でかつ前記ろ過器の器内温度が予め定められた温度上昇速度以下になるように前記入口弁および出口弁を開閉させる弁開閉信号を演算する制御装置とを備えたものである。
【００１３】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項３に記載したように、前記ろ過器は、その入口側に系統水ラインの系統水用弁の入口側から分岐しバイパス用弁を介装したバイパスラインと、その系統水用弁の出口側に処理水用弁を介装して接続する処理水ラインと、この処理水ラインに設けたオーバフロー用弁と、前記ろ過器に接続されたパージ用弁と、前記ろ過器の入口側と出口側との圧力差を検出する差圧計と、そのろ過器内の温度を検出する温度計と、そのろ過器の入口側および出口側のうちいずれか少なくとも一方に補給水用弁を介装した補給水ラインとを備えたものである。
【００１４】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項４に記載したように、系統水ラインに設けられ中空糸膜フィルタを収容しかつ並列に配置する複数のろ過器と、前記系統水ラインと前記ろ過器の各々の入口側との間に設けられ、系統水を１箇所に集めて前記ろ過器のそれぞれに分配するマニホールドと、前記ろ過器のそれぞれから出た処理水を１箇所に集める合流管と、この合流管からの処理水を系統水ラインに案内する処理水ラインと、前記ろ過器の入口側と出口側との圧力差を検出する差圧計と、前記ろ過器の器内温度を検出する温度計とを備えたものである。
【００１５】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項５に記載したように、ろ過器は、その入口側と出口側との圧力差および器内の温度との信号のうち、いずれか少なくとも一方の信号に基づいて演算される弁開閉演算信号によって開閉させる入口弁を備えたものである。
【００１６】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項６に記載したように、前記マニホールドは、その入口側に系統水ラインから供給される系統水を１箇所に集める集水タンクを備えたものである。
【００１７】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項７に記載したように、前記処理水ラインは、処理水タンクを備えたものである。
【００１８】
また、本発明に係るろ過装置は、上述の目的を達成するために、請求項８に記載したように、ろ過装置は、発電プラントの低圧給水加熱器の出口側、湿分分離器と脱気器とを結ぶ蒸気管、脱気器と給水ポンプとの間、高圧給水加熱器の出口側のうち、いずれか少なくとも一以上の位置に設置したものである。
【００１９】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項９に記載したように、起動運転時、系統水ラインに設けられ、中空糸膜フィルタを収容するろ過器の入口側圧力と出口側圧力との圧力差が予め定められた圧力以下になるよう弁開閉信号を演算し、前記系統水ラインから供給される系統水の流量を制御する方法である。
【００２０】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項１０に記載したように、起動運転時、系統水ラインに設けられ中空糸膜フィルタを収容するろ過器の入口側圧力と出口側圧力との圧力差が予め定められた圧力以下で、かつ前記ろ過器の器内温度が予め定められた温度上昇速度以下になるよう前記ろ過器の入口および出口に設けられた入口弁および出口弁の弁開閉信号を演算し、前記系統水ラインから供給される系統水の流量を制御する方法である。
【００２１】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項１１に記載したように、起動運転時、ろ過器に水を予め満たしておく方法である。
【００２２】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項１２に記載したように、起動運転時、ろ過器に水を予め満たした後、通水を行う方法である。
【００２３】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項１３に記載したように、起動運転時、ろ過器内のガスをパージさせた後、水を満たす方法である。
【００２４】
また、本発明に係るろ過装置の運転方法は、上述の目的を達成するために、請求項１４に記載したように、起動運転時、ろ過器内のガスを不活性ガスで置換した後、水を満たす方法である。
【００２５】
【発明の実施の形態】
以下、本発明に係るろ過装置およびその運転方法の実施形態を図面および図面に付した符号を引用して説明する。
【００２６】
図１は、本発明に係るろ過装置およびその運転方法の第１実施形態であるろ過装置およびその運転方法を示す概念図である。
【００２７】
本実施形態に係るろ過装置は、系統水ラインとなる復水・給水ライン１に復水・給水用弁２を備えるとともに、系統水用弁である復水・給水用弁２の出口側の復水・給水ライン３に設けられ、処理水用弁４を介装させた処理水ライン５に接続するろ過器６と、このろ過器６の入口側と復水・給水ライン１の復水・給水用弁２の入口側とを接続させる、バイパス用弁１６を介装させたバイパスライン７とを備えている。
【００２８】
また、ろ過装置は、ろ過器６の入口側および出口側のそれぞれに第１補給水用弁８および第２補給水用弁９を介装させた補給水ライン１０と、ろ過器６内のガス等をパージさせるパージ用弁１１と、ろ過器６内の処理水のオーバフローを処理させるオーバフロー用弁１２とを備えている。
【００２９】
一方、ろ過器６は、器内に中空糸膜フィルタ１３を収容するとともに、器外に器内の温度を測定する温度計１４と器内の入口圧と出口圧の差圧を測定する差圧計１５とを備える一方、これら温度計１４、差圧計１５の検出信号に基づいてバイパスライン７のバイパス用弁１６、復水・給水用弁２および処理水用弁４のそれぞれに弁開閉信号を与える制御装置１７を備えている。
【００３０】
このような構成を備える本実施形態に係るろ過装置において、起動運転開始前、バイパス用弁１６と処理水ライン５の処理水用弁４は閉弁させ、復水・給水ライン１の復水・給水用弁２を開弁させ、復水・給水を復水・給水ライン１，３に流通させる。
【００３１】
ろ過器６に復水・給水の通水を開始するとき、本実施形態に係るろ過装置およびその運転方法は、差圧計１５から検出された差圧信号ａを制御装置１７に与え、ここで演算し、ろ過器６に収容する中空糸膜フィルタ１３が損傷あるいは座屈しない予め定められた設定差圧以下となる弁開度を求め、その弁開度演算信号ｂをバイパス用弁１６に与え、復水・給水の原水をろ過器６に供給する。
【００３２】
バイパス用弁１６を設定開度、例えば全開させた後、制御装置１７は、差圧計１５から検出された差圧信号ａが予め定められた設定差圧を超えないように弁開度を演算し、その弁開度演算信号ｃを処理水ライン５の処理水用弁４に与えて開弁させ、最後に設定開度、例えば全開させるとともに、この間、復水・給水用弁２も中空糸膜フィルタ１３が損傷等を起こさせない範囲内に弁開度が制御される。
【００３３】
このように、本実施形態に係るろ過装置およびその運転方法は、各弁の弁開度を制御した後、復水・給水の原水をろ過器６に流し、ここで原水に含まれる懸濁固形物等の除去を開始する。
【００３４】
次に、ろ過器６内の水温が上昇すると、その粘性が低下するので、本実施形態に係るろ過装置およびその運転方法は、ろ過器６内の差圧を予め定められた設定差圧下に維持させながら復水・給水用弁２を弁開度演算信号ｄによって閉弁させ、ろ過器６への原水供給量を増加させ、最後に定格流量に至らしめる。
【００３５】
起動運転開始操作中、本実施形態に係るろ過装置およびその運転方法は、復水・給水の温度上昇速度が高くなって中空糸膜フィルタ１３が損傷等を受けないように、温度計１４からの検出信号ｅと差圧計１５からの検出信号ａとに基づいて制御装置１７で弁開閉信号を演算し、その弁開閉演算信号ｄ，ｂ，ｃを復水・給水用弁２、バイパス用弁１６および処理水用弁４のそれぞれに与えて弁開度を調整する。
【００３６】
また、本実施形態に係るろ過装置およびその運転方法は、中空糸膜フィルタ１３に損傷等を与えないようにするため、復水・給水ライン１の復水・給水をろ過器６に通水する前に、ろ過器６内に体積変化が少なくなるよう水を予め満たし、差圧の変化を少なくさせることも行われる。この場合、パージ用弁１１とオーバフロー用弁１２を開弁させるとともに、第１補給水用弁８を開弁させ、補給ライン１０からの補給水をろ過器６に供給し、パージ用弁１１からガスを系外にパージさせる。
【００３７】
そして、パージ用弁１１から補給水がオーバフローしてろ過器６の入口側に水が満たされた後、パージ用弁１１を閉弁させる。さらに、オーバフロー用弁１２から補給水がオーバフローし、ろ過器６の出口側に水が満たされたとき、第１補給水用弁８およびオーバフロー用弁１２を閉弁させる。
【００３８】
このとき、差圧計１５の検出値が予め定められた設定差圧を超えないように、補給水の供給量が調整される。なお、ろ過器６の出口側に水を張る場合、第１補給水用弁８の代りに第２補給水用弁９を使用すれば、差圧を常に監視していなくとも補給水を供給することができ、時間の短縮につながる。
【００３９】
また、ろ過器６を水で満たした後、第１補給水用弁８からろ過器６に補給水ライン１０の補給水を供給し、オーバフロー用弁１２で水をオーバフローさせながら、中空糸膜フィルタ１３の膜内の気体をパージすると、膜の有効面積を増加させ、差圧の上昇を抑制することができるので、起動運転時間を比較的短くすることができる。
【００４０】
さらに、ろ過器６を水で満たすとき、パージ用弁１１およびオーバフロー用弁１２からポンプなどでガスのパージを併用すると、ろ過器６を系統に接続した場合、系統への酸素等のガスの供給が減り、溶存酸素等に基づく機器の腐食を抑制することができる。なお、補給水に不活性ガスを加えて水張テストを行えば、補給水中に含まれる酸素等の溶存化を少なくして機器の腐食を抑制することができる。
【００４１】
このように、本実施形態に係るろ過装置およびその運転方法は、中空糸膜フィルタ１３を収容するろ過器６の入口側をバイパスライン７を介して復水・給水ライン１に接続し、ろ過器６の出口側を処理水ライン５を介して復水・給水ライン３に接続し、各ライン１，７，５，３に介装させた各弁２，４，１６にろ過器６の差圧または温度の信号ａ，ｅに基づいて弁開閉信号ｄ，ｃ，ｂを演算する制御装置１７を備え、この制御装置１７から各弁２，４，１６に中空糸膜フィルタ１３が損傷しないように弁開閉信号ｄ，ｃ，ｂを与えて流量調整するので、ろ過器６に安定した運転を行わせることができる。
【００４２】
図２は、本発明に係るろ過装置およびその運転方法の第２実施形態であるろ過装置およびその運転方法を示す概念図である。
【００４３】
本実施形態に係るろ過装置は、系統水ラインである復水・給水ライン１に設けた復水・給水用弁２の入口側から分岐するマニホールド１８と、このマニホールド１８から並列に配置する第１ろ過器６ａ、第２ろ過器６ｂおよび第３ろ過器６ｃと、これら各ろ過器６ａ，６ｂ，６ｃから出た処理水を合流させる合流管１９と、この合流管１９から出た処理水を復水・給水用弁２の出口側に設けた復水・給水ライン３に戻す処理水ライン５とを備えたものである。
【００４４】
第１ろ過器６ａ、第２ろ過器６ｂおよび第３ろ過器６ｃは、それぞれ器内に中空糸膜フィルタ１３ａ，１３ｂ，１３ｃを収容するとともに、器外に器内の温度を測定する温度計１４ａ，１４ｂ，１４ｃおよび器内の入口部と出口部の圧力差を測定する差圧計１５ａ，１５ｂ，１５ｃのそれぞれを備える一方、入口側に第１入口弁２０ａ、第２入口弁２０ｂ、第３入口弁２０ｃをそれぞれを設け、出口側に第１出口弁２０ａ、第２出口弁２０ｂ、第３出口弁２０ｃをそれぞれ設けたものである。
【００４５】
このような構成を備える本実施形態に係るろ過装置において、例えば第１ろ過器６ａに復水・給水を通水するとき、第１実施形態と同様に、温度計１４ａおよび差圧計１５ａのそれぞれからの検出した温度信号および差圧信号に基づいて制御装置（図示せず）で弁開閉信号を演算し、その弁開閉演算信号を第１入口弁２０ａに与えて圧力調整した後、第１出口弁２１ａを開弁させる。なお、第２ろ過器６ｂ、第３ろ過器６ｃのそれぞれに復水・給水を通水するときも上述と同様な操作が行われる。
【００４６】
このように、本実施形態に係るろ過装置およびその運転方法は、複数のろ過器６ａ，６ｂ，６ｃを並列に配置し、各ろ過器６ａ，６ｂ，６ｃを自由に選択することによって復水・給水の処理を調整するので、各ろ過装置の個々の仕様に合せて設計することがなく、製造コストの低減化を図ることができる。
【００４７】
また、本実施形態に係るろ過装置およびその運転方法は、複数のろ過器を並列に配置したので、一つのろ過器が何らかの事情で故障しても、残りの他のろ過器で復水・給水の処理を行うことができ、復水・給水の処理を停止させることなく連続処理を行わせることができる。
【００４８】
なお、本実施形態に係るろ過装置およびその運転方法は、複数のろ過器６ａ，６ｂ，６ｃを並列に配置し、各ろ過器６ａ，６ｂ，６ｃの入口側に第１入口弁２０ａ、第２入口弁２０ｂ、第３入口弁２０ｃのそれぞれを介装させて共通のマニホールド１８を備えたが、この例に限らず、例えば、図３に示すように、さらに追設してマニホールド１８の入口側に、第１復水・給水用弁２ａを備えた第１復水・給水ライン１ａ、第２復水・給水用弁２ｂを備えた第１復水・給水ライン１ｂ、第３復水・給水用弁２ｃを備えた第１復水・給水ライン１ｃのそれぞれからバイパスされる第１バイパスライン７ａ、第２バイパスライン７ｂ、第３バイパスライン７ｃから供給される復水・給水の原水を１箇所に集める集水タンク２２を設けるとともに、各ろ過器６ａ，６ｂ，６ｃで復水・給水の原水を処理した処理水を一旦集合管１９で集合させ、その集合水を他の系統に供給する連絡管５に一旦処理水を集める処理水タンク２３を設けてもよい。
【００４９】
なお、第１から第３の実施形態においては、プラントにおける系統水ラインとして発電プラントにおける復水・給水ラインについて説明したが、化学プラントにおける系統水ライン、廃棄物処理プラントにおける水処理系等の中空糸を採用したろ過器を用いたプラントに採用することができるのは勿論である。
【００５０】
図４は、発電プラントに組み込んだ本発明に係るろ過装置の第４実施形態を示す概念図である。
【００５１】
発電プラントは、蒸気発生器２４、高圧タービン２５、湿分分離器２６、低圧タービン２７、復水器２８、脱塩装置２９、低圧給水加熱器３０、脱気器３１、給水ポンプ３２、高圧給水加熱器３３を備えた復水・給水の循環回路になっている。
【００５２】
また、発電プラントは、湿分分離器２６で分離したドレンを加熱源として脱気器３１に供給し、脱気器３１内の復水・給水に含まれている溶存酸素を加熱脱気させる蒸気管３４と、高圧タービン２５からの高圧タービン抽気を高圧給水加熱器３３に供給して復水・給水を予熱させる高圧タービン抽気管３５と、低圧タービンからの低圧タービン抽気を低圧給水加熱器３０に供給して復水・給水を予熱させる低圧タービン抽気管３６とを備えている。
【００５３】
このような構成を備える発電プラントにおいて、本実施形態に係るろ過装置は、高圧給水加熱器３３の出口側、脱気器３１と給水ポンプ３２との間、湿分分離器２６と脱気器３１とを結ぶ蒸気管３４、低圧給水加熱器３０の出口側のうち、いずれか少なくとも一つ以上の位置にろ過器６を設けたものである。
【００５４】
したがって、本実施形態に係るろ過装置によれば、高圧給水加熱器３３の出口側、脱気器３１と給水ポンプ３２との間、湿分分離器２６と脱気器３１とを結ぶ蒸気管３４、低圧給水加熱器３０の出口側のうち、いずれか少なくとも一つ以上の位置に第１から第３の実施形態に係るろ過装置を設け、復水・給水あるいは高圧給水加熱器３３から脱気器３１に戻すヒータドレンに含まれる懸濁物等をろ過器６で除去する構成にしたので、懸濁物等の付着に起因するポンプの振動を抑制し、懸濁物付着による低圧給水加熱器３０、高圧給水加熱器３３、蒸気発生装置２４に組み込まれている伝熱管の腐食抑制伝熱効率の低下等を防止することができる。
【００５５】
【発明の効果】
以上の説明のとおり、本発明に係るろ過装置およびその運転方法は、ろ過器に収容する中空糸膜フィルタで系統水に含まれる懸濁物等を除去する際、器内を流れる系統水の差圧・温度に基づいて弁開閉信号を演算し、その弁開閉演算信号を系統水ラインに設けた系統水用弁、ろ過器の入口側のバイパスラインに設けたバイパス用弁、ろ過器の出口側の連絡管に設けた処理水用弁のそれぞれに与え、中空糸膜フィルタの損傷が発生しないように系統水の流量を制御するので、ろ過装置の運転を運転して行うことができる。
【００５６】
また、本発明に係るろ過装置およびその運転方法は、ろ過器に収容する中空糸膜フィルタで系統水に含まれる懸濁物等を除去する際、ろ過器を並列に配置させ、並列に配置させた各ろ過器に収容する中空糸膜フィルタで系統水を浄化させるので、運転中、一つのろ過器に事故が発生しても残りのろ過器で運転することができ、系統水の浄化を連続的に行うことができる。
【図面の簡単な説明】
【図１】本発明に係るろ過装置およびその運転方法の第１実施形態を示す概念図。
【図２】本発明に係るろ過装置およびその運転方法の第２実施形態を示す概念図。
【図３】本発明に係るろ過装置およびその運転方法の第３実施形態を示す概念図。
【図４】本発明に係るろ過装置の適用例を示す発電プラントの概念図。
【符号の説明】
１ 復水・給水ライン（系統水ライン）
１ａ 第１復水・給水ライン
１ｂ 第２復水・給水ライン
１ｃ 第３復水・給水ライン
２ 復水・給水弁
２ａ 第１復水・給水弁
２ｂ 第２復水・給水弁
２ｃ 第３復水・給水弁
３ 復水・給水ライン
４ 処理水用弁
５ 処理水ライン
６ ろ過器
６ａ 第１ろ過器
６ｂ 第２ろ過器
６ｃ 第３ろ過器
７ バイパスライン
７ａ 第１バイパスライン
７ｂ 第２バイパスライン
７ｃ 第３バイパスライン
８ 第１補給水用弁
９ 第２補給水用弁
１０ 補給水ライン
１１ パージ用弁
１２ オーバフロー用弁
１３ａ，１３ｂ，１３ｃ 中空糸膜フィルタ
１４ａ，１４ｂ，１４ｃ 温度計
１５ａ，１５ｂ，１５ｃ 差圧計
１６ バイパス用弁
１７ 制御装置
１８ マニホールド
１９ 合流管
２０ａ 第１入口弁
２０ｂ 第２入口弁
２０ｃ 第３入口弁
２１ａ 第１出口弁
２１ｂ 第２出口弁
２１ｃ 第３出口弁
２２ 集水タンク
２３ 処理水タンク
２４ 蒸気発生器
２５ 高圧タービン
２６ 湿分分離器
２７ 低圧タービン
２８ 復水器
２９ 脱塩装置
３０ 低圧給水加熱器
３１ 脱気器
３２ 給水ポンプ
３３ 高圧給水加熱器
３４ 蒸気管
３５ 高圧タービン抽気管
３６ 低圧タービン抽気管[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is a power generation plant, a start-up operation of a chemical plant, etc., a condensate system, a condensate / filtration device that effectively removes suspended solids contained in fluid flowing in various plants and condensate / water supplied to a water supply system, and It relates to the driving method.
[0002]
[Prior art]
A method for removing suspended solids from a fluid flowing in various plants will be described below with reference to a power generation plant. In a power plant such as a thermal power plant or a nuclear power plant, during startup operation, a condensate / water supply treatment device is provided as a filtration device for removing suspended solids such as iron oxide contained in the condensate / water supply. ing.
[0003]
This condensate / water supply treatment device has a hollow fiber membrane filter made of a polymer material such as polyethylene as a module, accommodates the module in a filter, and treats the treated water from the outside to the inside of the hollow fiber membrane filter. Flow to remove suspended matter at the membrane surface. The modular hollow fiber membrane filter is replaced when the water quality during operation, for example, the conductivity, the pressure difference between the inlet and outlet of the filter, the yield of the treated water, etc., exceeds a predetermined amount. ing.
[0004]
By the way, during the start-up operation, the treated water has a low temperature and a relatively high viscosity. Therefore, the resistance of the flow of the treated water to the hollow fiber membrane is increased, and the hollow fiber membrane cannot filter its rated flow rate. In some cases, the hollow fiber membrane may be clogged.
[0005]
The means for preventing clogging is provided with a bypass line for connecting the inlet side and the outlet side of the filter accommodating the hollow fiber membrane to each other, and the valve provided on the bypass line is fully opened during the start-up operation, and gradually opened. An operation method in which the valve is fully closed when the rated flow rate is reached by reducing the valve opening is disclosed, for example, in Japanese Patent Application Laid-Open No. H11-42424 (see Patent Document 1).
[0006]
[Patent Document 1]
JP-A-11-42424
[Problems to be solved by the invention]
Japanese Patent Application Laid-Open No. 11-42424 has a valve in a bypass line connecting an inlet side and an outlet side of a filter, and gradually narrows this valve from a fully opened state so that treated water does not flow rapidly into the hollow fiber membrane filter. Therefore, although it is excellent in that the flow resistance given to the hollow fiber membrane is reduced, it still has some problems, one of which is a means for coping with pressure fluctuation.
[0008]
In some cases, the condensate / feed water treatment device flows high-temperature / high-pressure treated water to the bypass line from the beginning of the operation start. When high-temperature and high-pressure treated water flows into the bypass line, pressure fluctuations occur because the opening degree of the valve is gradually reduced, and the treated water flashes (boils). When the treated water is flushed, the bypass line can no longer suppress it, and the effect is finally transmitted to the hollow fiber membrane filter, and the hollow fiber membrane filter is seated by a pressure difference (pressing force) based on pressure fluctuation. In some cases, it succumbs and significantly lowers its original processing capacity.
[0009]
In addition, during the temperature raising process before entering the rated operation, the viscosity of the treated water decreases, and the water permeability increases. For this reason, the hollow fiber membrane filter has problems that it softens, cannot withstand the pressure difference caused by pressure fluctuation, buckles, and cannot sufficiently handle the rated amount of the treated water.
[0010]
The present invention has been made in view of such circumstances, and has been made to maintain a pressure difference between an inlet side and an outlet side of a hollow fiber membrane filter housed in a filter so as to be always a constant value. It is an object of the present invention to provide a filtration device for automatically controlling the opening of a valve so that the rate of temperature rise of water always becomes a constant value and stably operating a hollow fiber membrane filter, and an operation method thereof.
[0011]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, a filtration device according to the present invention is provided at a plant, which is provided with a hollow fiber membrane filter, and which is provided at an inlet and an outlet of the filter, as described in claim 1. Control for calculating a valve opening / closing signal for opening / closing the inlet valve and the outlet valve such that the pressure difference between the inlet pressure and the outlet pressure of the filter becomes equal to or less than a predetermined pressure. And an apparatus.
[0012]
Further, in order to achieve the above object, a filtration device according to the present invention has a filter provided in a plant and containing a hollow fiber membrane filter, and an inlet and an outlet of the filter, as described in claim 2. The inlet valve and the outlet valve provided in the filter, the pressure difference between the inlet pressure and the outlet pressure of the filter is a predetermined pressure or less and the temperature inside the filter of the filter is a predetermined temperature rise rate or less And a controller for calculating a valve opening / closing signal for opening and closing the inlet valve and the outlet valve.
[0013]
Further, in order to achieve the above-mentioned object, the filter according to the present invention, as described in claim 3, has the filter branched from the inlet side of the system water valve of the system water line to the inlet side thereof. A bypass line interposed with a bypass valve, a treated water line connected to an outlet side of the system water valve with a treated water valve interposed therebetween, an overflow valve provided in the treated water line, A purge valve connected to the filter, a differential pressure gauge for detecting a pressure difference between an inlet side and an outlet side of the filter, a thermometer for detecting a temperature in the filter, and an inlet side of the filter And a makeup water line with a makeup water valve interposed on at least one of the outlet side.
[0014]
Further, in order to achieve the above-mentioned object, the filtration device according to the present invention includes a plurality of filtration devices provided in a system water line and accommodating hollow fiber membrane filters and arranged in parallel. And a manifold provided between the system water line and the inlet side of each of the filters, for collecting system water at one place and distributing the system water to each of the filters, and a treatment exiting from each of the filters. A merging pipe for collecting water at one place, a treated water line for guiding treated water from the merging pipe to a system water line, a differential pressure gauge for detecting a pressure difference between an inlet side and an outlet side of the filter, And a thermometer for detecting the inside temperature of the filter.
[0015]
Further, in order to achieve the above object, the filter according to the present invention, as described in claim 5, has a filter which is a signal of a pressure difference between an inlet side and an outlet side and a temperature inside the vessel. And an inlet valve that is opened and closed by a valve opening / closing operation signal calculated based on at least one of the signals.
[0016]
In addition, in order to achieve the above object, in the filtration device according to the present invention, the manifold collects the system water supplied from the system water line at one point in the manifold at the inlet side. It has a water collection tank.
[0017]
Moreover, in order to achieve the above-mentioned object, in the filtration device according to the present invention, the treated water line is provided with a treated water tank.
[0018]
Further, in order to achieve the above-mentioned object, the filtration device according to the present invention is configured such that the filtration device includes an outlet side of a low-pressure feedwater heater of a power plant, a moisture separator, and a deaerator. It is installed at at least one of at least one of a steam pipe connecting the vessel, a space between the deaerator and the water supply pump, and an outlet side of the high pressure water heater.
[0019]
In addition, in order to achieve the above-mentioned object, a method for operating a filtration device according to the present invention is provided in a system water line at the time of start-up operation to accommodate a hollow fiber membrane filter. This is a method for controlling the flow rate of system water supplied from the system water line by calculating a valve opening / closing signal so that the pressure difference between the inlet side pressure and the outlet side pressure of the vessel becomes equal to or less than a predetermined pressure.
[0020]
In addition, in order to achieve the above object, a method of operating a filtration device according to the present invention provides a filter that is provided in a system water line and accommodates a hollow fiber membrane filter in a system water line, as described in claim 10. The pressure difference between the inlet side pressure and the outlet side pressure is equal to or less than a predetermined pressure, and provided at the inlet and the outlet of the filter so that the inside temperature of the filter is equal to or less than a predetermined temperature rising rate. And calculating the valve opening / closing signals of the inlet valve and the outlet valve, and controlling the flow rate of system water supplied from the system water line.
[0021]
Further, the operating method of the filtration device according to the present invention is a method in which the filter is filled in advance with water during the start-up operation, in order to achieve the above-mentioned object.
[0022]
In addition, in order to achieve the above object, a method of operating a filtration device according to the present invention includes, as described in claim 12, a method in which water is passed after a filter is filled with water in advance during startup operation. It is.
[0023]
In addition, in order to achieve the above-mentioned object, a method of operating a filtration device according to the present invention includes a method of purging gas in a filter during a start-up operation and then filling the water with water as described in claim 13. It is.
[0024]
In addition, in order to achieve the above object, the operation method of the filtration device according to the present invention, as described in claim 14, performs water replacement after replacing the gas in the filter with an inert gas during startup operation. Is a way to satisfy
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a filtration device and a method of operating the filtration device according to the present invention will be described with reference to the drawings and reference numerals attached to the drawings.
[0026]
FIG. 1 is a conceptual diagram illustrating a filtration device and a method for operating the filtration device according to a first embodiment of the present invention.
[0027]
The filtration apparatus according to the present embodiment includes a condensate / water supply valve 2 in a condensate / water supply line 1 serving as a system water line, and a condensate / water supply valve 2 on the outlet side of the system water valve. A filter 6 provided in the water / water supply line 3 and connected to a treated water line 5 provided with a treated water valve 4 interposed therebetween, and a condensate / water supply of the inlet side of the filter 6 and the condensate / water supply line 1. And a bypass line 7 having a bypass valve 16 interposed therebetween for connecting the inlet side of the valve 2.
[0028]
Further, the filtration device includes a makeup water line 10 in which a first makeup water valve 8 and a second makeup water valve 9 are interposed on the inlet side and the outlet side of the filter 6, respectively. A purge valve 11 for purging the water and the like, and an overflow valve 12 for treating an overflow of the treated water in the filter 6 are provided.
[0029]
On the other hand, the filter 6 accommodates the hollow fiber membrane filter 13 inside the vessel, and a thermometer 14 for measuring the inside temperature outside the vessel and a differential pressure gauge for measuring the differential pressure between the inlet pressure and the outlet pressure inside the vessel. And a valve opening / closing signal to each of the bypass valve 16, the condensate / water supply valve 2, and the treated water valve 4 of the bypass line 7 based on the detection signals of the thermometer 14 and the differential pressure gauge 15. The control device 17 is provided.
[0030]
In the filtration device according to the present embodiment having such a configuration, before the start-up operation is started, the bypass valve 16 and the treated water valve 4 of the treated water line 5 are closed, and the condensed water / water supply line 1 is condensed / condensed. The water supply valve 2 is opened, and the condensed water / water supply flows through the condensed water / water supply lines 1 and 3.
[0031]
When the condensing / supplying of water to the filter 6 is started, the filtering device and the operation method thereof according to the present embodiment provide the differential pressure signal a detected from the differential pressure gauge 15 to the control device 17, where the calculation is performed. Then, a valve opening that is equal to or less than a predetermined set differential pressure at which the hollow fiber membrane filter 13 accommodated in the filter 6 is not damaged or buckled is obtained, and the valve opening calculation signal b is given to the bypass valve 16, Raw water for condensate / supply is supplied to the filter 6.
[0032]
After the bypass valve 16 is set to a preset opening, for example, fully opened, the control device 17 calculates the valve opening so that the differential pressure signal a detected from the differential pressure gauge 15 does not exceed a predetermined differential pressure. The valve opening degree calculation signal c is supplied to the treated water valve 4 of the treated water line 5 to open the valve, and finally the set opening degree, for example, is fully opened. The valve opening is controlled within a range where the filter 13 does not cause damage or the like.
[0033]
As described above, in the filtering device and the operation method according to the present embodiment, after controlling the valve opening of each valve, the raw water of the condensed water / supply water flows into the filter 6, where the suspended solids contained in the raw water are The removal of objects etc. is started.
[0034]
Next, when the water temperature in the filter 6 rises, its viscosity decreases. Therefore, the filtering device and the operation method thereof according to the present embodiment maintain the differential pressure in the filter 6 at a predetermined set differential pressure. Then, the condensate / water supply valve 2 is closed by the valve opening calculation signal d to increase the amount of raw water supplied to the filter 6 and finally reach the rated flow rate.
[0035]
During the start-up operation start operation, the filtration device and the operation method according to the present embodiment are provided with a thermometer 14 from the thermometer 14 so that the temperature rise rate of the condensate / supply water is increased and the hollow fiber membrane filter 13 is not damaged. Based on the detection signal e and the detection signal a from the differential pressure gauge 15, the controller 17 calculates a valve opening / closing signal, and converts the valve opening / closing calculation signals d, b, c into the condensate / water supply valve 2, the bypass valve 16 And to each of the treated water valves 4 to adjust the valve opening.
[0036]
In addition, in the filtration device and the operation method according to the present embodiment, the condensate / water supply of the condensate / water supply line 1 is passed through the filter 6 so as not to damage the hollow fiber membrane filter 13. Before that, the filter 6 may be filled with water in advance so as to reduce the volume change to reduce the change in the differential pressure. In this case, the purge valve 11 and the overflow valve 12 are opened, the first makeup water valve 8 is opened, and makeup water from the makeup line 10 is supplied to the filter 6. The gas is purged out of the system.
[0037]
After the makeup water overflows from the purge valve 11 and the inlet side of the filter 6 is filled with water, the purge valve 11 is closed. Further, when makeup water overflows from the overflow valve 12 and the outlet side of the filter 6 is filled with water, the first makeup water valve 8 and the overflow valve 12 are closed.
[0038]
At this time, the supply amount of the makeup water is adjusted so that the detection value of the differential pressure gauge 15 does not exceed a predetermined set differential pressure. When water is supplied to the outlet side of the filter 6, if the second makeup water valve 9 is used instead of the first makeup water valve 8, the makeup water is supplied even if the differential pressure is not constantly monitored. Can save time.
[0039]
After filling the filter 6 with water, the supply water of the makeup water line 10 is supplied to the filter 6 from the first makeup water valve 8, and the water is overflowed by the overflow valve 12. Purging the gas in the film 13 increases the effective area of the film and suppresses the increase in the differential pressure, so that the start-up operation time can be relatively shortened.
[0040]
Further, when the filter 6 is filled with water, the purging of the gas from the purge valve 11 and the overflow valve 12 by a pump or the like is also used. When the filter 6 is connected to the system, supply of gas such as oxygen to the system is performed. And corrosion of equipment based on dissolved oxygen and the like can be suppressed. In addition, if the water filling test is performed by adding an inert gas to the makeup water, the dissolution of oxygen and the like contained in the makeup water can be reduced and the corrosion of the equipment can be suppressed.
[0041]
As described above, in the filtration device and the operation method according to the present embodiment, the inlet side of the filter 6 accommodating the hollow fiber membrane filter 13 is connected to the condensate / water supply line 1 via the bypass line 7. 6 is connected to the condensate / water supply line 3 via the treated water line 5 and the differential pressure of the filter 6 is applied to each of the valves 2, 4, and 16 interposed in the lines 1, 7, 5, and 3, respectively. Alternatively, a control device 17 for calculating the valve opening / closing signals d, c, b based on the temperature signals a, e is provided, and the control device 17 prevents the valves 2, 4, 16 from damaging the hollow fiber membrane filter 13. Since the flow rate is adjusted by giving the valve opening / closing signals d, c, and b, the filter 6 can be operated stably.
[0042]
FIG. 2 is a conceptual diagram showing a filtration device and a method for operating the filtration device according to a second embodiment of the present invention.
[0043]
The filtration device according to the present embodiment includes a manifold 18 branching from an inlet side of a condensate / water supply valve 2 provided in a condensate / water supply line 1 which is a system water line, and a first arrangement arranged in parallel from the manifold 18. The filter 6a, the second filter 6b, and the third filter 6c, a merging pipe 19 for merging the treated water from the respective filters 6a, 6b, 6c, and a treated water flowing out of the merging pipe 19 are returned. A treated water line 5 is provided on the outlet side of the water / water supply valve 2 and returns to the condensate / water supply line 3.
[0044]
Each of the first filter 6a, the second filter 6b, and the third filter 6c accommodates a hollow fiber membrane filter 13a, 13b, 13c inside the vessel, and a thermometer 14a for measuring the temperature inside the vessel outside the vessel. , 14b, 14c and differential pressure gauges 15a, 15b, 15c for measuring the pressure difference between the inlet and outlet in the vessel, while the first inlet valve 20a, the second inlet valve 20b, the third inlet are provided on the inlet side. A valve 20c is provided, and a first outlet valve 20a, a second outlet valve 20b, and a third outlet valve 20c are provided on the outlet side.
[0045]
In the filtration device according to the present embodiment having such a configuration, for example, when condensed water / supply water is supplied to the first filter 6a, similarly to the first embodiment, each of the thermometer 14a and the differential pressure gauge 15a A control device (not shown) calculates a valve opening / closing signal based on the detected temperature signal and differential pressure signal, gives the valve opening / closing calculation signal to the first inlet valve 20a, adjusts the pressure, and then adjusts the first outlet valve. The valve 21a is opened. The same operation as described above is performed when condensing and supplying water to each of the second filter 6b and the third filter 6c.
[0046]
As described above, the filtration device and the operation method thereof according to the present embodiment are configured such that the plurality of filters 6a, 6b, and 6c are arranged in parallel, and each of the filters 6a, 6b, and 6c is freely selected to condense water. Since the treatment of the water supply is adjusted, the production cost can be reduced without designing the filter in accordance with the individual specifications of each filtration device.
[0047]
In addition, in the filtering device and the operation method according to the present embodiment, since a plurality of filters are arranged in parallel, even if one filter fails for some reason, condensing and supplying water with the remaining other filters. And the continuous treatment can be performed without stopping the condensate / supply water treatment.
[0048]
The filtering device and the operation method according to the present embodiment include a plurality of filtering devices 6a, 6b, 6c arranged in parallel, and a first inlet valve 20a, a second filtering device, and a second filtering device on the inlet side of each filtering device 6a, 6b, 6c. Although the common manifold 18 is provided by interposing each of the inlet valve 20b and the third inlet valve 20c, the present invention is not limited to this example. For example, as shown in FIG. A first condensate / water supply line 1a provided with a first condensate / water supply valve 2a, a first condensate / water supply line 1b provided with a second condensate / water supply valve 2b, a third condensate / water supply Raw water supplied from the first bypass line 7a, the second bypass line 7b, and the condensed water supplied from the third bypass line 7c, which is bypassed from each of the first condensate / water supply lines 1c provided with the valve 2c. And a water collection tank 22 The treated water obtained by treating the condensed water / supply water in the filters 6a, 6b, 6c is once collected in the collecting pipe 19, and the collected water is once collected in the connecting pipe 5 for supplying the collected water to another system. 23 may be provided.
[0049]
In the first to third embodiments, the condensate / water supply line in the power plant has been described as the system water line in the plant, but the system water line in the chemical plant, the hollow water treatment system in the waste treatment plant, and the like. Needless to say, it can be adopted in a plant using a filter employing a yarn.
[0050]
FIG. 4 is a conceptual diagram showing a fourth embodiment of the filtration device according to the present invention incorporated in a power plant.
[0051]
The power plant includes a steam generator 24, a high-pressure turbine 25, a moisture separator 26, a low-pressure turbine 27, a condenser 28, a desalination unit 29, a low-pressure feedwater heater 30, a deaerator 31, a feedwater pump 32, and a high-pressure feedwater. A condensing / supplying water circulation circuit having a heater 33 is provided.
[0052]
Further, the power generation plant supplies the drain separated by the moisture separator 26 as a heating source to the deaerator 31, and heats and degass dissolved oxygen contained in the condensate / water supply in the deaerator 31. A pipe 34, a high-pressure turbine bleed pipe 35 for supplying high-pressure turbine bleed air from the high-pressure turbine 25 to the high-pressure feedwater heater 33 to preheat condensate and feedwater, and a low-pressure turbine bleed air from the low-pressure turbine to the low-pressure feedwater heater 30 And a low-pressure turbine bleed pipe 36 for supplying and preheating condensed water / supply water.
[0053]
In the power plant having such a configuration, the filtration device according to the present embodiment includes an outlet side of the high-pressure feed water heater 33, between the deaerator 31 and the feed pump 32, the moisture separator 26 and the deaerator 31. The filter 6 is provided at any one or more of the steam pipe 34 connecting to the outlet and the outlet side of the low-pressure feedwater heater 30.
[0054]
Therefore, according to the filtration device of the present embodiment, the steam pipe 34 connecting the moisture separator 26 and the deaerator 31 between the outlet side of the high-pressure feed water heater 33, the deaerator 31 and the water supply pump 32. The filter device according to the first to third embodiments is provided at at least one or more positions on the outlet side of the low-pressure feed water heater 30, and the deaerator is connected to the condensate / water feed or high-pressure feed water heater 33. Since the suspension and the like contained in the heater drain returned to 31 are configured to be removed by the filter 6, vibration of the pump caused by the adhesion of the suspension and the like is suppressed, and the low-pressure feed water heater 30 due to the adhesion of the suspension and the like. It is possible to prevent corrosion of the heat transfer tube incorporated in the high-pressure feed water heater 33 and the steam generator 24 and to prevent a decrease in heat transfer efficiency.
[0055]
【The invention's effect】
As described above, the filtration device and the operation method thereof according to the present invention provide a method of removing a suspension or the like contained in system water by a hollow fiber membrane filter housed in the filter, when the system water flowing through the system is removed. A valve opening / closing signal is calculated based on the pressure and temperature, and the valve opening / closing calculation signal is used for the system water valve provided on the system water line, the bypass valve provided on the bypass line on the inlet side of the filter, and the outlet side of the filter. And the flow rate of the system water is controlled so as not to cause damage to the hollow fiber membrane filter, so that the operation of the filtration device can be performed.
[0056]
Further, the filtration device and the operation method thereof according to the present invention, when removing the suspended matter and the like contained in the system water with the hollow fiber membrane filter housed in the filter, the filter is arranged in parallel, the filter is arranged in parallel Since the system water is purified by the hollow fiber membrane filters housed in each filter, even if one filter has an accident during operation, it can be operated with the remaining filters, and continuous purification of the system water can be performed. Can be done
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a first embodiment of a filtration device and an operation method thereof according to the present invention.
FIG. 2 is a conceptual diagram showing a second embodiment of a filtration device and an operation method thereof according to the present invention.
FIG. 3 is a conceptual diagram showing a third embodiment of the filtration device and the operation method thereof according to the present invention.
FIG. 4 is a conceptual diagram of a power plant showing an application example of the filtration device according to the present invention.
[Explanation of symbols]
1 Condensation / water supply line (system water line)
1a First condensate / water supply line 1b Second condensate / water supply line 1c Third condensate / water supply line 2 Condensate / water supply valve 2a First condensate / water supply valve 2b Second condensate / water supply valve 2c Third condensate Water / water supply valve 3 Condensate / water supply line 4 Treated water valve 5 Treated water line 6 Filter 6a First filter 6b Second filter 6c Third filter 7 Bypass line 7a First bypass line 7b Second bypass line 7c Third bypass line 8 First make-up water valve 9 Second make-up water valve 10 Make-up water line 11 Purge valve 12 Overflow valves 13a, 13b, 13c Hollow fiber membrane filters 14a, 14b, 14c Thermometers 15a, 15b , 15c Differential pressure gauge 16 Bypass valve 17 Controller 18 Manifold 19 Merging pipe 20a First inlet valve 20b Second inlet valve 20c Third inlet valve 21a First outlet valve 21b Second outlet valve 21c Third Mouth valve 22 Water collecting tank 23 Treated water tank 24 Steam generator 25 High-pressure turbine 26 Moisture separator 27 Low-pressure turbine 28 Condenser 29 Desalination device 30 Low-pressure water heater 31 Deaerator 32 Water pump 33 High-pressure water heater 34 Steam pipe 35 High pressure turbine bleed pipe 36 Low pressure turbine bleed pipe
