應用實績>瑞典(VIVAB)污水處理廠採用Hach VFA線上分析儀監測厭氧過程
VIVAB tests Volatile Fatty Acids Online Analyzer in Anaerobic Processes
Monitoring and optimizing the production of volatile fatty acids (VFA) and controlling the alkalinity and pH in anaerobic processes are essential factors to prevent acute failures and bottlenecks in digesters and biological phosphorous-removal (EBPR) plants.
監測和優化厭氧過程中揮發性脂肪酸(VFA)的產生並控制鹼度和pH值是防止消化槽和生物除磷(EBPR)廠出現嚴重故障和瓶頸的重要因素。
 
Online measurement instruments present a good opportunity to monitor such processes, as they enable constant determination of the conditions inside a digester. One such instrument is the online analyzer AnaSense*, which facilitates monitoring, controlling, optimising, and protecting the anaerobic process. This instrument measures the following parameters, namely, pH, VFA, bicarbonates, and total and partial alkalinity. It was tested by the Swedish Municipal Joint Stock
Company (VIVAB [Vatten & Miljö i Väst AB]) at three different sites and the same samples were analyzed using three different laboratory methods.
線上監測儀器為監測厭氧過程提供很好的機會,因為它可以持續監測消化槽內部的狀況。水中VFA線上分析儀AnaSense *(AppliTek EZ7200 VFA線上分析儀)監視,控制,優化和保護厭氧過程。 測量參數為: pH,VFA,碳酸氫鹽以及總鹼度和部分鹼度。瑞典市政股份公司(VIVAB [Vatten&Miljo i Vast AB])以此監測方法在三個不同地點分別進行測試,並且使用三種不同的實驗室方法來對相同的水樣進行了分析。
 
Installation on sites
Getteröverket WWTP 污水處理廠
Getteröverket, located in the municipality of Varberg, is one of the largest wastewater treatment plants of VIVAB. It has a treatment capacity of 5,600 kg BOD7/day, which is equivalent to 80,000 PE (population equivalent). This conventional WWTP generally processes domestic sewage, with approximately only 7% of the inlet BOD7 load originating from industrial wastewater, mainly from the fish industry. The WWTP has four digesters with a total volume of 3,600 m3, i.e. each reactor has a volume of 900 m3.
Getteröverket位於瑞典瓦爾貝格市,是VIVAB最大的污水處理廠之一。 它的處理能力為每天5,600 kg BOD7,相當於80,000 PE(人口當量)。 此傳統的污水處理廠通常處理生活污水,大約只有7%的BOD7浸水來自工業廢水,主要的是來自漁產加工業。污水處理廠有四個消化槽,總容積為3600立方米,即每個消化槽的容量為900立方米。
 
The AnaSense analyzer was connected to the master reactor because the widest process variations were expected to occur in this reactor. Furthermore, it was expected that process instability owing to an increase of VFA and a decrease of alkalinity would be perceivable first in this reactor. Such developments could be caused, for instance, by changes in the organic load and pre-thickening.
由於預期此消化槽會發生很大的程序變化,因此將AnaSense分析儀連接到主消化槽。 此外,由於預期VFA增加和鹼度降低,會觀察到消化槽內反應過程的不穩定。 此發展可能是由於有機負荷的變化和預濃縮而引起。
 
Carlsberg Pre-treatment 嘉士伯啤酒廠預處理 
Various industries are located in the Falkenberg municipal area or next to this city. Owing to the unstable conditions of industrial wastewater, treatment of the water at the largest WWTP, Smedjeholmen, presents a significant challenge. In particular, the wastewater from the Carlsberg brewery requires specific pre-treatment. The outlet process water from the brewery is pre-treated in an anaerobic internal circular reactor (IC reactor) located in the southern part of the municipality of Falkenberg. VIVAB is responsible for the maintenance and operation of this facility. The process water is treated in the IC reactor mainly for two purposes, namely to enhance biogas production and to decrease the BOD load prior to treatment at the Smedjeholmen WWTP.
很多工業位於法爾肯貝格市轄區或附近。 由於工業廢水的不穩定性,最大的污水處理廠Smedjeholmen的水處理面臨巨大挑戰,特別是,來自嘉士伯啤酒廠的廢水需要進行特定的預處理。 來自啤酒廠的排放水是在位於法爾肯貝格市南部的厭氧內部循環消化槽(IC消化槽)內進行預處理。 VIVAB負責設施的維護和營運。 在IC反應器內對過程用水進行處理主要有兩個目的,即在Smedjeholmen污水處理廠進行處理之前,要提高沼氣的產量並降低BOD負荷。
 
Ullared WWTP 烏拉勒德污水處理廠
The WWTP at Ullared is located in the municipal area of Falkenberg. It treats mainly influent water from the prem ises at the shopping centre at Gekås, which houses shops, restaurants, and a camping site. Accordingly, drastic changes and fluctuations occur in the hydraulic and the BOD loads in the inlet water during shopping hours and holidays. The WWTP at Ullared has a treatment capacity of 518 kg BOD7/day, which is equivalent to 7,400 PE. The WWTP was constructed as a biological phosphorous-removal plant (BIO-P) and a recirculated activated sludge pro cess (ARP) for VFA production is used.
The wastewater treatment process at Ullared WWTP consists of three main steps, namely, mechanical treatment, followed by biological treatment, and, finally, treatment in the polishing ponds.

烏拉勒德Ullared污水處理廠位於瑞典法肯貝格市轄區。 它主要處理Gekås購物中心的廢水,此購物中心設有商店,餐廳和露營地。 因此,在購物時間和假日期間,進水口的水力和BOD負荷值會有劇烈變化和波動。 烏拉勒德污水處理廠的日處理能力為518公斤BOD7 /天,相當於7,400 PE。 此污水處理廠是建造為生物除磷廠(BIO-P),並採用用於VFA生產的再循環活性污泥處理法(ARP)。 烏拉勒德污水處理廠的廢水處理過程包括三個主要步驟,即機械處理,然後是生物處理,最後是在拋光池中進行處理。
 
Results and Discussion 結果和討論
Getteröverket WWTP 污水處理廠
研究結果有助於評估和提升Getteröverket污水處理廠的消化槽程序。 由於入口流量穩定,消化槽中的鹼度和VFA值相當穩定。 透過細查線上測量結果,明顯看出即使是過程中的微小變化或事件也可立即辨認出來,例如離心機的停止。 顯示出此VFA線上監測儀具有改善程序,降低能耗和降低成本的潛力。 如果全年都省去增稠劑,則聚合物的消耗量從3.8噸/年(2015年)降低至零,聚合物成本每年可節省高達150,000瑞典克朗(15,500美元)。 此外,提高污泥(棄水懸浮物)的脫水性,可降低污泥的運輸成本並減少內部循環。
與線上測量結果之間的比較顯示,經過優化後,所有圖形都依循相同的趨勢(圖1)。
 
由於VIVAB進行額外的過濾程序,VIVAB方法的值低於線上測量值。除了VFA值較高之外,透過AnaSense方法獲得的值的範圍與線上測量方法的值相似。 從法爾肯貝里(Falkenberg)方法獲得的值始終低於線上測量值,這是由於水樣的額外過濾程序。 瓦爾貝格(Varberg)認證實驗室的結果顯示,所有測量值都在不同的範圍內,但依循相同的趨勢(圖2和圖3)。
 
Carlsberg 嘉士伯啤酒廠 
鹼度的數值變化很快且不規則,而普通VFA值則相當穩定,在30 mg/L至55 mg/L的小範圍內波動。如果結合進水流量處的 TOC 線上監測,VFA 的測量將更加有用。 根據這些關鍵參數,可以調節進入消化槽的進水流量。 線上測量值與實驗室值之間的比較顯示,所有值都依循相同的趨勢,顯示分析儀運作正常(圖4和5)。
 
Ullared 烏拉勒德汙水處理廠 
與之前的試驗相比,Ullared污水處理場這裡獲得的整體線上結果更不穩定。 這是由於ARP中的鹼度和VFA含量比厭氧消化池中通常獲得的水準明顯的低。 然而,獲得的結果顯示趨勢是準確的,並且依循ARP過程中的預期變化,這加強了監測的可靠度。 在整個期間內,對線上測量結果和實驗室結果進行比較。 實驗室的數值顯示所有值都依循相同的趨勢,顯示分析儀運作正常(圖6)。
 
Conclusion 
The focus during the test trials with the AnaSense instrument was establishing whether the analysis results were trust worthy and whether the analyzer was a useful instrument to monitor the pro cesses at wastewater treatment plants. The evaluation of the instrument indi cated that the online measurement values were indeed correct. A compar ison between the online measurements and the measurements obtained in the laboratory indicated that the given values from the analyzer were reliable and that all the values followed the same trend. Even small changes in the process were identifiable, based on these results. Therefore, it is possible to optimize the process without the risk of acidification of the reactor. At Get teröverket WWTP, it was possible to improve the process by bypassing the pre-thickener, which could save up to 150,000 SEK per year ($15,500 USD) and could lower the cost of transport of the sludge.
使用AnaSense分析儀(EZ7200 系列線上 VFA)進行試驗的重點是確定分析結果是否可信,以及分析儀是否是監測污水處理廠程序的有效儀器。 對於儀器的評估顯示,線上測量值確實是準確的。 線上測量值和實驗室測量值之間的結果比較顯示出分析儀的測值是可靠的,且所有測量值都依循相同的趨勢。 根據這些結果可以得出即使是程序中微小的變化也可以被識別出來。 因此,有可能優化程序而沒有消化槽酸化的風險。 Getteröverket污水處理廠可以省略預濃縮來改善程序,這樣每年可節省多達150,000瑞典克朗(15,500美元)並降低污泥運輸成本。
 
Authors
Dr. Alexander Keucken, Research Manager; Moshe Habagil, R&D Engineer,
Caroline Schleich, Environmental Engineer, R&D Department, VIVAB
Application Notes (點進下方標題即可瀏覽原文) Language Size Date Edition
Volatile Fatty Acids in Anaerobic Processes: VIVAB tests Volatile Fatty Acids Online Analyser
DOC043.53.30567
English UK 406 KB 2020-07 Jul20