Hach污水生化需氧量BOD, 化學需氧量COD, 總有機碳TOC濃度之監測
BOD, COD and TOC Monitoring in Pulp & Paper Wastewater 污水生化需氧量化學需氧量總有機碳濃度之監測
Introduction
The pulp and paper production process is a water-intensive process that also generates a large amount of wastewater characterized by a high concentration of suspended solids (SS), COD, TOC and biochemical oxygen demand (BOD).
The volume and pollution load of the generated wastewater depends upon several factors. Various raw materials and chemicals are added to the process of manufacturing different types of paper. The wastewater discharged can have a negative impact on aquatic and land ecosystems and possibly result in fines.
While water reuse and recycling programs are part of the solution, accurate lab and in-process measurements of TSS, COD, BOD and TOC levels allow for treatment prior to discharge. The time needed to perform each test can vary from a few minutes to several days.
紙漿造紙製程是一個耗水量大的過程,同時也會產生大量的廢水,這類廢水的特點是懸浮物體(SS)、COD、TOC和生化需氧量(BOD)的濃度很高。
產生的廢水容量和污染負荷量視幾個因素而定。 在製造不同類型紙張的過程中會添加各種原材料和化學品。 排放的廢水會對水生和陸地生態系統產生負面影響,並可能導致罰款。
雖然解決方案包括了水再利用和水循環計劃,不過取得TSS、COD、BOD 和 TOC 濃度的實驗室和線上的準確測量值就能在廢水排放前即先進行適宜的處理。 執行每個測試的所需時間可能從幾分鐘到幾天不等。
 
Organic Matter Analysis 有機物分析
 
Biochemical Oxygen Demand
BOD is the amount of oxygen used during the biological breakdown of organic material i.e. the quantity of oxygen removed from rivers and water ways etc. BOD is considered an indirect measure of the organic content of a sample. ➔BOD measurement is a 5 or 7 day laboratory process.
BOD 是有機物質的生物分解過程中所使用的氧氣量,即從河流和水道等中去除的氧氣量。BOD 被認為是水樣中有機物含量的間接量度。 ➔BOD 測量是一個 5 或 7 天的實驗室過程。
 
Chemical Oxygen Demand
COD is the equivalent amount of oxygen needed to breakdown organic matter using strong oxidizing agents. It is an approximation of BOD. ➔CODcr measurement is a 2 – 2.5 hour laboratory process.
COD 是使用強氧化劑分解有機物所需的當量氧氣。 它是 BOD 的近似值。 ➔CODcr 測量是一個 2 ~ 2.5 小時的實驗室過程。
 
Total Organic Carbon
TOC is a direct measure of the Carbon content of dissolved and un-dissolved Organic matter present in a sample.
TOC measurement is a 6-10 minute on-line measurement.
TOC 是水樣中溶解和未溶解有機物碳含量的直接量度。➔TOC 測量是 6 ~ 10 分鐘的線上測量過程。
 
 
TOC Correlation with BOD/COD
TOC analysis, is an alternative to BOD5 and COD, and TOC is a more cost effective, accurate and timely test with less interferences and also has the capability to be used for process control and real-time monitoring. Stable correlation between parameters can be achieved†.
TOC 分析是 BOD5 和 COD 的替代方法,TOC 是一種更具成本效益、準確和及時的測試,干擾更少,且具有應用於過程控制和即時監控的能力。 可以達成參數之間的穩定相關性†。
 
Wastewater is considered readily biodegradable if it has a BOD:COD ratio greater than 0.4. If the BOD:COD ratio is less than 0.4, biodegradation will proceed very slowly, then it is not possible to treat biologically. If the wastewater of a paper mill is not highly biodegradable it is due to the presence of non-biodegradable compounds like lignin, which create a challenge for treatment.
如果廢水的 BOD:COD 比率大於 0.4,則認為廢水易於生物降解。 如果 BOD:COD 比率小於 0.4,則生物降解將非常緩慢,無法進行生物處理。 如果造紙廠的廢水不是非常能夠生物降解的,那是由於有木質素等不可生物降解的化合物,而這給廢水處理帶來挑戰。
 
† There are no fixed correlation factors between the inclusions BOD, COD and TOC.
† The correlation of parameters depends on the composition of the sample (matrix).
† The only way to establish a correlation is to use comparative data over a long period of time.
† Conversion factors established on the basis of long-term comparison will only be valid for the given plant / sample flow under stable matrix conditions
 
What Hach can offer you as your trusted partner for water analysis?  Hach完整水質分析方案
 
Laboratory Methods 實驗室分析方案
Measure BOD using BOD Instruments. Measure Suspended Solids with the TSS Portable. Measure COD* and TOC using DR3900 or DR6000 spectrophotometers.
 
The Next Generation in On-line BOD/COD/TOC Analysis: BioTector  新一代線上BOD/COD/TOC 分析儀 BioTector
The ideal online TOC Analyzer to achieve precise results even for your most challenging applications in wastewater.
理想的線上TOC 分析儀,即使在廢水中最具挑戰性的應用中也能獲得精確的結果。
 
Online Sensors and Controllers: Suspended Solids: Solitax sc Sensors  懸浮固體Solitax sc 線上數位感測器和數位控制器
Hach’s digital Solitax sc process probes are designed for the accurate determination of turbidity and suspended solids in accordance with DIN EN ISO. Due to a very large measuring range for both turbidity and solids the Solitax sc family offers a broad application spectrum and is ideal for pulp & paper wastewater and sludge treatment applications.
Hach Solitax sc 線上數位感測器是根據 DIN EN ISO 國際標準而設計以準確測定濁度和懸浮固體。 由於濁度和懸浮固體的量測範圍非常廣,Solitax sc 系列感測器提供廣泛的應用範圍,是紙漿和造紙廢水和污泥處理應用設備的理想選擇。
 
Manage Product Loss and Protect Profits in Pulp and Paper Manufacturing by Monitoring Nutrients and Solids  透過監測營養物質和懸浮固體來管理紙漿和造紙製程中的產品耗損進而保護利潤
Plant managers can gain valuable insight into plant operations by tracking product loss over time, which can be done simply by collecting and tracking data in two key areas: Nutrient Optimization and Solids Management.
污水處理廠管理人員可以追蹤隨著時間變化的產品耗損量以洞悉與污水處理廠運作有關的寶貴關鍵資訊,而這能夠透過蒐集追蹤兩個關鍵數據來完成:營養物質優化和懸浮固體管理。
 
 
Source : Hach US Application Note