基于PLC的造紙廢水中段水控制系統(tǒng)設(shè)計(jì)

電氣自動(dòng)化論文編號(hào):ZD676    論文字?jǐn)?shù):28039,頁(yè)數(shù):67

目 錄
摘  要 I
ABSTRACT II
1 緒論 1
1.1 引言 1
1.2 國(guó)內(nèi)外發(fā)展?fàn)顩r 2
2 方案選定 3
2.1 厭氧法 3
2.1.1 升流式厭氧污泥反應(yīng)器（UASB） 3
2.1.2 內(nèi)循環(huán)（IC）厭氧反應(yīng)器 3
2.2 SBR+絮凝沉淀法處理中段水 4
2.3 好氧處理法 5
2.4 方案確定 7
3 中段水好氧處理的自動(dòng)控制 8
3.1控制工藝流程 8
3.2 液位控制設(shè)計(jì) 9
3.3 進(jìn)反應(yīng)器廢水溫度控制 10
3.4 PH控制單元設(shè)計(jì) 11
3.5 營(yíng)養(yǎng)物質(zhì)投加控制 13
4 硬件部分設(shè)計(jì) 14
4.1 PLC控制系統(tǒng)設(shè)計(jì)原則和設(shè)計(jì)步驟 14
4.2控制總體要求 16
4.3系統(tǒng)硬件配置 16
4.4  PLC選型及傳感器的連接 17
4.5硬件連接圖 24
4.5.1電氣控制A柜 24
4.5.2 電氣控制B柜 28
4.5.2 電氣控制C柜 28
5 中段水PLC控制程序部分設(shè)計(jì) 30
5.1 STEP7軟件的設(shè)計(jì)步驟 30
5.2 程序總體設(shè)計(jì)方案 30
總結(jié) 37
致謝 38
參考文獻(xiàn) 39
附錄Ⅰ 控制地址表 40
附錄Ⅱ 子程序介紹 54

摘  要
  造紙廢水按產(chǎn)工藝主要分三部分：蒸煮黑液，中段廢水，紙機(jī)網(wǎng)下白水。中段廢水的處理是重點(diǎn)和難點(diǎn)。制漿中段廢水指的是經(jīng)黑液提取后的蒸煮漿料在洗滌，篩選，漂白以及打漿的過(guò)程中所派出的廢水。
   文章針對(duì)制漿中段廢水的特點(diǎn)特出了一套結(jié)構(gòu)簡(jiǎn)單應(yīng)用效果良好的中段廢水好氧處理過(guò)程控制方案。廢水處理采用好氧生化處理技術(shù)，利用好氧微生物在多氧條件下對(duì)有機(jī)物的很強(qiáng)大的分解功能，采用人工的控制技術(shù)從而去除造紙中段廢水中的BOD、COD以及SS成分。針對(duì)中段水處理工藝要求以及好氧處理控制過(guò)程特點(diǎn)，采用基于S7-300PLC的DCS控制系統(tǒng)。結(jié)合過(guò)程控制原理，可以實(shí)現(xiàn)報(bào)警、監(jiān)控以及先進(jìn)算法自動(dòng)控制的系統(tǒng)。
 該方案采用上位監(jiān)控計(jì)算機(jī)和下位機(jī)PLC相結(jié)合的控制方法。上位監(jiān)控計(jì)算機(jī)負(fù)責(zé)與PLC進(jìn)行通訊，對(duì)整個(gè)廢水處理流程進(jìn)行監(jiān)視和操作，并具有數(shù)據(jù)記錄、故障報(bào)警、參數(shù)設(shè)置等功能。下位機(jī)PLC對(duì)現(xiàn)場(chǎng)的PH、流量、溫度，液位信號(hào)及泵閥的運(yùn)行情況、故障等信號(hào)進(jìn)行采集，并根據(jù)預(yù)先編制的控制程序輸出控制各種泵閥的指示信號(hào)，同時(shí)完成將下位機(jī)的信號(hào)傳到監(jiān)控計(jì)算機(jī)內(nèi)以接受監(jiān)控計(jì)算機(jī)指令。
關(guān)鍵詞：PLC，中段水，好氧處理，控制系統(tǒng)

ABSTRACT
 Paper production process wastewater in accordance with the main three parts: cooking liquor, the middle of wastewater, under the White Paper Network. The middle of wastewater treatment is a key and difficult. Pulp and refers to the middle of wastewater extracted by the cooking liquor in the pulp washing, screening, bleaching and beating in the process of sending the waste water.
 In this paper, pulp and the middle of the characteristics of wastewater outstanding application of a simple structure of the middle effective aerobic treatment of wastewater process control program. Wastewater treatment using aerobic biological and chemical processing technology, the use of aerobic micro-organisms in the anoxic conditions of organic matter decomposition is a powerful feature, the use of artificial control technology in order to remove the paper in the middle of wastewater BOD, COD and SS components. Requirements for mid-water treatment process and characteristics of aerobic treatment process control, based on S7-300PLC's DCS control system. Combined with the principle of process control can be achieved alarm, monitoring, and advanced automatic control system algorithm.
 The computer program used to monitor upper and lower PLC integrated control methods. Host is responsible for monitoring the computer to communicate with the PLC of the entire wastewater treatment process monitoring and operation and has a data recording, fault alarm, parameter setting functions. PLC-bit on-site under the PH, flow, temperature, liquid level signal and pump operation, fault, such as signal acquisition, and in accordance with pre-control procedures for the preparation of the various pump output control signal instructions, at the same time to complete the next-bit machine signal reached the monitoring computer monitoring computer to accept commands.
KEYWORDS: PLC, the middle of water, aerobic treatment, the control system