ここで、「押し出し」とは、系内の薬液（塩基性洗浄液又は過酸化水素洗浄液）を純水で追い出すこと、即ち純水による薬液置換で、同一系での押し出しなら使用薬液の薬品濃度に依存せず押し出し工程時間はほぼ同じとなり、理想的には系の容量の１倍量分の純水を用いる。また、「リンス」とは押し出し後に、配管表面に付着したり、配管溜りや、継ぎ手部分に残っている薬品を純水で綺麗に洗い流す（リンスする）ことで、同一系であっても使用薬液の薬品濃度に依存して洗浄時間は異なってくるもので、高濃度の場合ほど長時間が必要になる。「押し出し」では、例えば純水貯槽を純水に置換してから、ポンプを使いサブシステムに該純水を一気に流し込んでリターン配管の末端近辺からブローする等の操作を行う。本明細書では、「押し出し」と「リンス」の両者を纏めて「押し出し洗浄」と言うこともある。従って、純水による塩基性洗浄液の押し出しとリンスとを行う工程を「第一の押し出し洗浄工程」、純水による過酸化水素洗浄液の押し出しとリンスとを行う工程を「第二の押し出し洗浄工程」とも言うものとする。また、押し出し洗浄の際の「純水」は「超純水」の場合もあり、純水又は超純水を用いると考えればよい。
Here, “extrusion” means that the chemical solution in the system (basic cleaning solution or hydrogen peroxide cleaning solution) is purged with pure water, that is, chemical replacement with pure water. The extrusion process time is almost the same without depending on it, and ideally, pure water equivalent to one volume of the system capacity is used. “Rinse” is a chemical solution that can be used even in the same system by exfoliating (rinsing) chemicals that adhere to the pipe surface or remain in the pipe pool or joints with pure water after extrusion. The cleaning time varies depending on the chemical concentration, and the higher the concentration, the longer the time required. In the “extrusion”, for example, the pure water storage tank is replaced with pure water, and then the pure water is poured into the subsystem at once using a pump and blown from the vicinity of the end of the return pipe. In the present specification, both “extrusion” and “rinsing” may be collectively referred to as “ extrusion cleaning”. Therefore, the process of extruding and rinsing the basic cleaning solution with pure water is the “first extrusion cleaning process”, and the process of extruding and rinsing the hydrogen peroxide cleaning solution with pure water is the “second extrusion cleaning process”. It shall also be said. In addition, “pure water” at the time of extrusion cleaning may be “ultra pure water”, and it may be considered that pure water or ultra pure water is used.
図２は、図１の様なサブシステムを含む超純水製造供給装置の一例を示す配管系統図である。一次純水はラインＬ１を通って純水貯槽１１に送られる。純水貯槽１１とラインＬ２及びＬ３でタンク循環系（薬液調製循環系）を構成して均一な薬液を調製する際に用いられる。シャワーボール１２は純水貯槽１１の内壁にも液を散布する様になっている。通常運転中はラインＬ７にある弁Ｖ２は閉じた状態である。新規立ち上げ時あるいは定期検査等による休止後の再立ち上げ時には弁Ｖ２の先にラインＬ８を仮設し、弁Ｖ２を開き、ラインＬ８とラインＬ７を介してＴＭＡＨやアンモニア等のアルカリ薬剤の塩基性洗浄原液（濃厚薬液）又は過酸化水素原液（濃厚薬液）のそれぞれ所定量をラインＬ２に注入する。その際、ラインＬ２上にある弁Ｖ３の開度を調節することで上記濃厚薬液と循環液の流量を調節し、ポンプＰにより弁Ｖ５を開いたラインＬ３を経由して純水貯槽１１に貯留されている純水に上記濃厚薬液を導入して、タンク循環系を循環させることにより純水と混合し、均一な薬液として調製する。この際、弁Ｖ４は閉じておくのが好ましい。上記濃厚薬液の注入手順としては、例えば、洗浄した綺麗な容器に濃厚薬液を張り、チューブなどの仮設ラインＬ８を介して注入し、液が少なくなったら空気が入らない様に容器に純水を入れて残存薬液を注入する様な操作を繰り返すことによって、所定量の濃厚薬液を注入することができる。また、それぞれの濃厚薬液注入後はラインＬ８、ラインＬ７を純水で洗浄し、弁Ｖ２は閉じ、仮設ラインＬ８は撤去する。純水貯槽１１の内壁を純水で洗浄（リンス）する際は弁Ｖ１及びＶ６を閉じ、弁Ｖ７を開き、ラインＬ１から分岐したラインを通して一次純水をシャワーボール１２から散布するのが好ましい。調製された薬液を洗浄に用いる際は、弁Ｖ２及びＶ５を閉じ、弁Ｖ４を開いて、ポンプＰで薬液をサブシステム１３に送り込み、使用場所に超純水を送る配管系であるラインＬ４、ユースポイント配管系、残余の超純水を戻すリターン配管系であるラインＬ５を包含する超純水製造供給装置の循環系に薬液を行き渡らせる。ラインＬ６は、押し出し洗浄の初期の段階で一気にブローするのに用いるバイパスラインで、これを用いる際は弁Ｖ８を閉じ、弁Ｖ９を開く。弁Ｖ１０は圧力制御弁であり、循環洗浄の際や通常運転の際などの圧力や流量を制御する。排水ブローの際には弁Ｖ１１を開き、弁１２を閉じるが、循環系の通常運転の際には弁Ｖ１２を開き、弁１１を閉じる。計器１４は、ｐＨ、導電率、又は抵抗率等の水質を測定する測定計器である。図２では、測定計器１４は分岐したサンプリングラインＬ９上にあるが、例えばラインＬ５等のメインライン上にあってもよい。分岐の場合、各水質はオンライン測定でも、オフライン測定でもよい。また、測定計器１４は、常時設置ではなく、装置立ち上げ試運転用に仮設置してもよい。
FIG. 2 is a piping diagram showing an example of an ultrapure water production and supply apparatus including the subsystem as shown in FIG. The primary pure water is sent to the pure water storage tank 11 through the line L1. The pure water storage tank 11 and the lines L2 and L3 constitute a tank circulation system (chemical solution preparation circulation system) and are used when preparing a uniform chemical solution. The shower ball 12 sprays liquid also on the inner wall of the pure water storage tank 11. During normal operation, the valve V2 on the line L7 is closed. At the time of new start-up or at the time of re-start-up after a pause due to periodic inspections, etc., a line L8 is temporarily installed at the end of the valve V2, the valve V2 is opened, and the basicity of alkali chemicals such as TMAH and ammonia via the lines L8 and L7 A predetermined amount of each of the cleaning stock solution (concentrated chemical solution) or the hydrogen peroxide stock solution (concentrated chemical solution) is injected into the line L2. At that time, the flow rate of the concentrated chemical solution and the circulating fluid is adjusted by adjusting the opening degree of the valve V3 on the line L2, and stored in the pure water storage tank 11 via the line L3 where the valve V5 is opened by the pump P. The concentrated chemical solution is introduced into the pure water and mixed with pure water by circulating through the tank circulation system to prepare a uniform chemical solution. At this time, the valve V4 is preferably closed. Examples of the concentrated chemical solution injection procedure, for example, span the concentrated chemical solution to clean container and washed, and injected through a temporary setting line L8, such as a tube, pure water in the container so as to prevent air from entering When the liquid becomes less A predetermined amount of concentrated chemical solution can be injected by repeating the operation of injecting the remaining chemical solution. Further, after each of the concentrated liquid injection is cleaning line L8, line L7 with pure water, closing the valve V2, the temporary setting line L8 is removed. When cleaning (rinsing) the inner wall of the pure water storage tank 11 with pure water, the valves V1 and V6 are closed, the valve V7 is opened, and primary pure water is preferably sprayed from the shower ball 12 through a line branched from the line L1. When the prepared chemical liquid is used for cleaning, the valves V2 and V5 are closed, the valve V4 is opened, the chemical liquid is sent to the subsystem 13 by the pump P, and a line L4 which is a piping system for sending ultrapure water to the place of use, The chemical solution is distributed to the circulation system of the ultrapure water production and supply apparatus including the line L5 which is the return point piping system for returning the remaining ultrapure water. Line L6 is a bypass line used for blowing at a stroke in the initial stage of extrusion cleaning. When this is used, valve V8 is closed and valve V9 is opened. The valve V10 is a pressure control valve, and controls the pressure and flow rate during circulating cleaning and normal operation. During drainage blow, the valve V11 is opened and the valve 12 is closed, but during normal operation of the circulation system, the valve V12 is opened and the valve 11 is closed. The meter 14 is a measuring meter that measures water quality such as pH, conductivity, or resistivity. In FIG. 2, the measuring instrument 14 is on the branched sampling line L9, but may be on the main line such as the line L5. In the case of branching, each water quality may be measured online or offline. Moreover, the measuring instrument 14 may be temporarily installed for the apparatus start-up test operation instead of being always installed.