化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
6期
2256-2263
,共8页
白四红%陈彤%祁志福%刘洁%陆胜勇%薄拯%李晓东
白四紅%陳彤%祁誌福%劉潔%陸勝勇%薄拯%李曉東
백사홍%진동%기지복%류길%륙성용%박증%리효동
热脱附%载气流量%停留时间%升温速率%多氯联苯%二英%热降解
熱脫附%載氣流量%停留時間%升溫速率%多氯聯苯%二英%熱降解
열탈부%재기류량%정류시간%승온속솔%다록련분%이영%열강해
thermal desorption%carrier gas flow rate%residue time%heating rate%polychlorinated biphenyls (PCBs)%polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/Fs)%thermal degradation
利用小型管式炉进行了载气流量和升温速率对多氯联苯污染土壤的热脱附过程影响的实验研究。结果表明流量的增大对多氯联苯含量和毒性当量的去除效率影响不大,载气流量小于400 ml·min-1时,气相中的脱附量明显增大,载气流量大于400 ml·min-1则脱附量变化较小,而多氯联苯的毒性当量则随着载气流量增大呈线性增加趋势。实验结果还表明污染土壤中多氯联苯变化速率与升温速率呈明显的正线性相关,随着升温速率增加,污染土壤中多氯联苯去除效率总体呈上升趋势,毒性当量去除效率降低。总体结果分析可以看到升温速率越大,总体效果也越好。污染土壤经热脱附处理后气固相的二英毒性当量则有不同程度提升,尤其气相内检测到了大量多氯二苯并呋喃生成。
利用小型管式爐進行瞭載氣流量和升溫速率對多氯聯苯汙染土壤的熱脫附過程影響的實驗研究。結果錶明流量的增大對多氯聯苯含量和毒性噹量的去除效率影響不大,載氣流量小于400 ml·min-1時,氣相中的脫附量明顯增大,載氣流量大于400 ml·min-1則脫附量變化較小,而多氯聯苯的毒性噹量則隨著載氣流量增大呈線性增加趨勢。實驗結果還錶明汙染土壤中多氯聯苯變化速率與升溫速率呈明顯的正線性相關,隨著升溫速率增加,汙染土壤中多氯聯苯去除效率總體呈上升趨勢,毒性噹量去除效率降低。總體結果分析可以看到升溫速率越大,總體效果也越好。汙染土壤經熱脫附處理後氣固相的二英毒性噹量則有不同程度提升,尤其氣相內檢測到瞭大量多氯二苯併呋喃生成。
이용소형관식로진행료재기류량화승온속솔대다록련분오염토양적열탈부과정영향적실험연구。결과표명류량적증대대다록련분함량화독성당량적거제효솔영향불대,재기류량소우400 ml·min-1시,기상중적탈부량명현증대,재기류량대우400 ml·min-1칙탈부량변화교소,이다록련분적독성당량칙수착재기류량증대정선성증가추세。실험결과환표명오염토양중다록련분변화속솔여승온속솔정명현적정선성상관,수착승온속솔증가,오염토양중다록련분거제효솔총체정상승추세,독성당량거제효솔강저。총체결과분석가이간도승온속솔월대,총체효과야월호。오염토양경열탈부처리후기고상적이영독성당량칙유불동정도제승,우기기상내검측도료대량다록이분병부남생성。
A real soil contaminated by high concentration polychlorinated biphenyl (PCBs) was heated in a tube furnace at various carrier gas flow rate and at various heating rate to investigate their effect on thermal desorption of PCBs in contaminated soil. With the rising of carrier gas flow rate, a slight increase of PCBs removal efficiency (from 93.5%to 95.1%) and toxic equivalency quantity (TEQ) in soil were observed. With increase of the flow rate desorption amount of PCBs was obvious large when it was lower than 400 ml·min-1, then a little chang at>400 ml·min-1, while TEQ of PCBs showed a trend of linear increase with the rising of flow rate. The TEQ of polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/Fs) in treated soil decreased, while in carrier gas a large increase of TEQ of PCDD/Fs especially PCDFs was observed.The removal rate of PCBs in soil showed a significant positive linear relationship with the heating rate. With the rising of heating rate, the removal efficiency of PCBs in soil increased, and the TEQ of PCBs had a little change. The desorption amount of PCBs decreased. The TEQ removal efficiency of PCDD/Fs increased. After thermal desoption there was significant formation of PCDD/Fs while there was TEQ high increase of PCDD/Fs. Generally, the effect of flow rate on the removal efficiency of PCBs in soil was less but on the desorption amount of PCBs was significant. Higher heating rate can make a better removal efficiency of PCBs and lower formation of PCDD/Fs.