Fine Bubble Aeration Oxygenation-Aquasust

Rahoton Gwaji

A cikin tsarin kula da ruwan datti, tsarin iskar da iska ya kai kashi 45 zuwa 75% na makamashin da ake amfani da shi na dukkan masana'antar kula da ruwan sha, domin inganta isar da iskar oxygen ta hanyar iskar iska, ana amfani da injin sarrafa ruwa na yanzu a cikin microporous. Aeration tsarin.Idan aka kwatanta da tsarin aeration na manya da matsakaita-sized kumfa, da microporous aeration tsarin iya ajiye game da 50% na makamashi amfani. Koyaya, ƙimar amfani da iskar oxygen na tsarin iskar sa shima yana cikin kewayon 20% zuwa 30%. Bugu da kari, an samu karin wurare a kasar Sin don yin amfani da fasahar iska mai karamin karfi wajen magance gurbatattun koguna, amma babu wani bincike kan yadda za a iya zabar iskar da ake bukata don yanayin ruwa daban-daban. Sabili da haka, haɓakawa na microporous aerator oxygenation sigogi na ayyuka don ainihin samarwa da aikace-aikacen yana da mahimmanci.

Akwai abubuwa da yawa da suka shafi aikin microporous aeration da oxygenation, mafi mahimmancin su shine ƙarar iska, girman pore da shigarwa na zurfin ruwa.

A halin yanzu, akwai ƙananan karatu game da dangantakar dake tsakanin aikin oxygenation na microporous aerator da girman pore da zurfin shigarwa a gida da waje. Binciken ya fi mayar da hankali kan inganta jimlar adadin iskar oxygen da ƙarfin iskar oxygen, kuma ya yi watsi da matsalar amfani da makamashi a cikin tsarin iska. Muna ɗaukar ingantaccen ƙarfin ka'idar azaman babban ma'aunin bincike, haɗe tare da ƙarfin iskar oxygen da yanayin amfani da iskar oxygen, da farko haɓaka ƙarar iska, diamita mai buɗewa da zurfin shigarwa lokacin da ingancin iska shine mafi girma, don samar da tunani don aikace-aikacen. na fasahar iskar iska ta microporous a cikin ainihin aikin.

1.Materials da hanyoyin

1.1 Gwajin saitin

An yi saitin gwajin da Plexiglas, kuma babban jiki shine D {0}}.4 m × 2 m tankin iskar siliki tare da narkar da binciken iskar oxygen dake 0.5 m ƙasa da saman ruwa (an nuna a hoto 1). ).

Hoto 1 Saitin Gwajin Iska da Oxygenation

1.2 Gwaji kayan

Microporous aerator, Ya yi da roba membrane, diamita 215 mm, pore size 50, 100, 200, 500, 1 000 μm. Sension378 benchtop narkar da oxygen tester, HACH, Amurka. Gas rotor kwarara mita, kewayon 0 ~ 3 m3 / h, daidaito ± 0.2%. HC-S abin busa. Mai haɓakawa: CoCl 2-6H2O, tsantsar nazari; Deoxidant: Na2SO3, analytically tsarki.

1.3 Hanyar gwaji

An gudanar da gwajin ne ta hanyar hanyar da ba ta tsaya tsaye ba, watau Na2SO3 da CoCl2-6H2O an fara yin alluran ne don samun iskar oxygen a lokacin gwajin, kuma an fara iska lokacin da iskar oxygen da ke cikin ruwa ta ragu zuwa {{5} }. An yi rikodin canje-canje a cikin narkar da iskar oxygen a cikin ruwa a kan lokaci, kuma an ƙididdige ƙimar KLa. An gwada aikin iskar oxygen a ƙarƙashin juzu'i daban-daban na iska (0.5, 1, 1.5, 2, 2.5, 3 m3/h), girman pore daban-daban (5{22}}, 100, 200, 500, 1, 000 μm), da kuma zurfin ruwa daban-daban (0.8, 1.1, 1.3, 1.5, 1.8, 2.0 m), kuma an yi nuni ga CJ/T

3015. 2 -1993 "Aerator clear water oxygenation determination" da kuma Amurka bayyana ma'aunin gwajin iskar oxygenation ruwa.

2.Sakamako da tattaunawa

2.1 Ka'idar gwajin

Babban ka'idar gwajin ta dogara ne akan ka'idar membrane sau biyu da Whitman ya gabatar a cikin 1923. Ana iya bayyana tsarin isar da iskar oxygen a cikin lissafi (1).

Inda: dc/dt - yawan canja wurin taro, watau, adadin iskar oxygen da aka canjawa kowace raka'a na ruwa a kowane lokaci, mg/(Ls).

KLa - jimlar isar da iskar oxygen ta iskar a yanayin gwaji, min{1}};

C * - cikakken narkar da iskar oxygen a cikin ruwa, mg/l.

Ct - narkar da iskar oxygen a cikin ruwa a lokacin iskar t, mg/L.

Idan zafin gwajin ba a digiri 20 ba, ana iya amfani da ƙima (2) don gyara KLa:

Ƙarfin oxygenation (OC, kg / h) yana bayyana ta hanyar ƙididdiga (3).

Inda: V - ƙarar tafkin aeration, m3.

Amfani da iskar oxygen (SOTE,%) ana bayyana shi ta hanyar lissafi (4).

Inda: q - ƙarar iska a daidaitaccen yanayin, m3 / h.

Ƙimar ƙarfin ka'idar [E, kg/(kW-h)] ana bayyana shi ta hanyar lissafi (5).

Inda: P - ikon kayan aikin aeration, kW.

Alamomin da aka saba amfani dasu don kimanta aikin iskar oxygenation shine jimlar iskar oxygen taro coefficient KLa, ƙarfin oxygenation OC, ƙimar amfani da iskar oxygen SOTE da ingantaccen ƙarfin ikon E [7]. Nazarin da ake ciki sun fi mayar da hankali kan yanayin jimlar adadin iskar oxygen, ƙarfin iskar oxygen da amfani da iskar oxygen, kuma ƙasa da ingantaccen ƙarfin ikon [8, 9]. Ƙimar ƙarfin ka'idar, a matsayin maƙasudin inganci kawai [10], na iya nuna matsalar amfani da makamashi a cikin tsarin iskar iska, wanda shine abin da wannan gwaji ya mayar da hankali.

2.2 Tasirin iska akan aikin oxygenation

An kimanta aikin iskar oxygenation a matakan iska daban-daban ta hanyar iska a ƙasan 2 m na aerator tare da girman rami na 200 μm, kuma an nuna sakamakon a cikin siffa 2.

Hoto 2 Bambancin K da amfani da iskar oxygen tare da yawan iska

Kamar yadda ake iya gani daga hoto na 2, KLa yana ƙaruwa a hankali tare da haɓakar ƙarar iska. Wannan shi ne yafi saboda girman ƙarar iska, mafi girma wurin hulɗar ruwan gas kuma mafi girman ingancin iskar oxygen. A gefe guda, wasu masu bincike sun gano cewa yawan amfani da iskar oxygen ya ragu tare da karuwar yawan iska, kuma an sami irin wannan yanayi a wannan gwaji. Wannan shi ne saboda a ƙarƙashin wani zurfin ruwa, lokacin zama na kumfa a cikin ruwa yana ƙaruwa lokacin da ƙarar iska ya yi ƙanƙara, kuma an tsawaita lokacin saduwa da ruwan gas; lokacin da yawan iskar iska ya yi yawa, hargitsin ruwa yana da ƙarfi, kuma yawancin iskar oxygen ɗin ba a yin amfani da su yadda ya kamata, kuma a ƙarshe ana fitar da su daga saman ruwa ta hanyar kumfa zuwa iska. Yawan amfani da iskar oxygen da aka samu daga wannan gwaji bai da yawa idan aka kwatanta da wallafe-wallafen, mai yiwuwa saboda tsayin dakaru bai isa ba, kuma yawan iskar oxygen ya tsere ba tare da tuntuɓar ginshiƙin ruwa ba, yana rage yawan amfani da iskar oxygen.

Bambance-bambancen ingantaccen ƙarfin ka'idar (E) tare da iska yana nunawa a cikin siffa 3.

Hoto na 3 Ƙarfin wutar lantarki tare da ƙarar iska

Kamar yadda ake iya gani a cikin hoto na 3, ingantaccen ikon ka'idar yana raguwa sannu a hankali tare da haɓaka iska. Wannan shi ne saboda daidaitaccen canjin iskar oxygen yana ƙaruwa tare da haɓakar ƙarar iska a ƙarƙashin wasu yanayi mai zurfi na ruwa, amma haɓakar aikin da ake amfani da shi ta hanyar busa ya fi mahimmanci fiye da haɓakar daidaitaccen canjin iskar oxygen, don haka ingantaccen ikon ka'idar. yana raguwa tare da haɓakar ƙarar iska a cikin kewayon ƙarar iska da aka bincika a cikin gwaji. Haɗa abubuwan da ke faruwa a cikin Figs. 2 da 3, ana iya gano cewa ana samun mafi kyawun aikin iskar oxygen a cikin ƙarar iska na 0.5 m3/h.

2.3 Sakamakon girman pore akan aikin oxygenation

Girman pore yana da tasiri mai girma akan samuwar kumfa, girman girman pore, girman girman kumfa. Kumfa a kan aikin oxygenation na tasirin yana bayyana a cikin bangarori biyu: Na farko, ƙananan kumfa guda ɗaya, mafi girman yanki na musamman na kumfa, ya fi girma da wurin canja wurin taro na ruwa, mafi dacewa ga canja wurin. oxygen; Abu na biyu, mafi girma da kumfa, da karfi da rawar da ke motsa ruwa, da gas-ruwa hadawa tsakanin sauri, mafi kyau sakamako na oxygenation. Sau da yawa batu na farko a cikin tsarin canja wurin taro yana taka muhimmiyar rawa. Jarabawar za ta zama ƙarar iskar da aka saita zuwa 0.5m3/h, don bincika tasirin girman pore akan KLa da amfani da iskar oxygen, duba Hoto 4.

Hoto 4 Bambance-bambancen lanƙwasa na KLa da amfani da iskar oxygen tare da girman pore

Kamar yadda ake iya gani daga hoto na 4, duka KLa da amfani da iskar oxygen sun ragu tare da karuwar girman pore. A ƙarƙashin yanayin zurfin ruwa iri ɗaya da ƙarar iska, KLa na 50 μm aperture aerator yana kusan sau uku na na 1,{3}} μm aperture aerator. Sabili da haka, lokacin da aka shigar da na'urar a cikin wani zurfin ruwa, ƙananan ƙarancin ƙarfin iskar oxygenation da amfani da iskar oxygen ya fi girma.

Bambance-bambancen ingantaccen ikon ka'idar tare da girman pore yana nunawa a cikin siffa 5.

Hoto 5 Ƙarfafa ƙarfin ka'ida da girman pore

Kamar yadda ake iya gani daga hoto na 5, ingantaccen ikon ka'idar yana nuna haɓakar haɓakawa sannan kuma raguwa tare da haɓaka girman buɗe ido. Wannan shi ne saboda a gefe guda, ƙananan buɗaɗɗen buɗaɗɗen buɗaɗɗen yana da mafi girma KLa da ƙarfin oxygenation, wanda ke da kyau ga oxygenation. A gefe guda, asarar juriya a ƙarƙashin wani zurfin ruwa yana ƙaruwa tare da raguwar diamita na budewa. Lokacin da raguwar girman pore akan asarar juriya na tasirin haɓakawa ya fi girma fiye da rawar da ake yi na iskar oxygen, za a rage yawan ƙarfin wutar lantarki tare da rage girman pore. Sabili da haka, lokacin da diamita na budewa ya kasance ƙananan, ƙimar ƙarfin ka'idar za ta karu tare da karuwar diamita na budewa, da diamita na 200 μm don kaiwa matsakaicin darajar 1.91 kg / (kW-h); lokacin da diamita na diamita> 200 μm, asarar juriya a cikin tsarin aeration ba ya taka muhimmiyar rawa a cikin tsarin aeration, KLa da ƙarfin oxygenation tare da karuwa a diamita na aerator za a rage, sabili da haka, ka'idar ingancin wutar lantarki yana nuna gagarumin ci gaba na ƙasa.

2.4 Sakamakon zurfin shigarwa na ruwa akan aikin oxygenation

Zurfin ruwan da aka shigar da na'urar yana da tasiri mai mahimmanci akan tasirin iska da oxygenation. Makasudin binciken gwajin shine tashar ruwa mara zurfi da ƙasa da 2 m. Zurfin iskar na'urar an ƙaddara ta zurfin ruwa na tafkin. Nazarce-nazarcen da ake da su sun fi mayar da hankali ne kan zurfin na'urar da ke nutsewa (watau, ana shigar da na'urar a kasan tafkin, kuma zurfin ruwa yana ƙaruwa ta hanyar ƙara yawan ruwa), gwajin ya fi mayar da hankali kan zurfin shigarwa na na'urar. aerator (watau adadin ruwan da ke cikin tafkin ana kiyaye shi akai-akai, kuma ana daidaita tsayin shigarwa na aerator don nemo mafi kyawun zurfin ruwa don tasirin iska), da canje-canjen KLa da amfani da iskar oxygen tare da zurfin an nuna ruwa a hoto na 6.

Hoto 6 Bambance-bambancen madaidaicin K da amfani da iskar oxygen tare da zurfin ruwa

Hoto na 6 yana nuna cewa tare da karuwar zurfin ruwa, duka KLa da amfani da oxygen suna nuna haɓakar haɓakar haɓaka, tare da KLa ya bambanta da fiye da sau hudu a 0.8 m zurfin ruwa da zurfin ruwa 2 m. Wannan shi ne saboda zurfin ruwa, tsawon lokacin zama na kumfa a cikin ginshiƙi na ruwa, tsawon lokacin hulɗar ruwan gas, mafi kyawun tasirin iskar oxygen. Sabili da haka, zurfin shigar da mai amfani da iska, mafi dacewa ga iyawar iskar oxygen da amfani da iskar oxygen. Amma shigar da zurfin ruwa yana ƙaruwa a lokaci guda asarar juriya kuma za ta karu, don shawo kan asarar juriya, wajibi ne a kara yawan iska, wanda ba makawa zai haifar da karuwar amfani da makamashi da farashin aiki. Sabili da haka, don samun zurfin shigarwa mafi kyau, ya zama dole don kimanta alaƙar da ke tsakanin ingantaccen ƙarfin wutar lantarki da zurfin ruwa, duba Table 1.

Tebur na 1 yana nuna cewa ƙimar ƙarfin ƙa'idar ta yi ƙasa sosai a zurfin shigarwa na {{1}.8m, tare da 0.5kg/(kW-h) kawai, wanda ke sa iskar ruwa mara zurfi bai dace ba. Shigar da zurfin ruwa na kewayon 1.1 ~ 1.5 m, saboda haɓakar haɓakar haɓakar iskar oxygenation, yayin da mai ba da iska ta hanyar juriya ba a bayyane yake ba, don haka ingantaccen ƙarfin ka'idar yana ƙaruwa da sauri. Yayin da zurfin ruwa ya kara karuwa zuwa 1.8 m, sakamakon asarar juriya a kan aikin oxygenation ya zama mafi mahimmanci, wanda ya haifar da haɓakar haɓakar ƙarfin ikon da ake amfani da shi yana kula da matakin kashewa, amma har yanzu yana nuna haɓakar haɓaka, kuma a cikin shigarwa. na zurfin ruwa na 2 m, ƙarfin ikon ka'idar ya kai matsakaicin 1.97 kg / (kW-h). Saboda haka, don tashoshi <2 m, an fi son aeration na ƙasa don mafi kyawun oxygenation.

Kammalawa

Yin amfani da madaidaiciyar hanyar da ba ta tsaya ba don iskar microporous bayyananniyar gwajin oxygenation na ruwa, a cikin zurfin ruwa na gwaji (< 2 m) and pore size (50 ~ 1 000 μm) conditions, the total oxygen mass transfer coefficient KLa and oxygen utilisation increased with the installation of the water depth; with the increase in pore size and decreased. In the process of increasing the aeration volume from 0.5 m3/h to 3 m3/h, the total oxygen mass transfer coefficient and oxygenation capacity gradually increased, and the oxygen utilisation rate decreased.

Ƙarfin ikon tunani shine kawai alamar tasiri. A cikin yanayin gwaje-gwaje, ingantaccen ikon ka'idar tare da aeration da shigar da zurfin ruwa yana ƙaruwa, tare da haɓaka buɗewar buɗewa da farko haɓaka sannan kuma raguwa. Shigar da zurfin ruwa da budewa ya kamata ya zama haɗuwa mai ma'ana don yin aikin oxygenation don cimma mafi kyau, a gaba ɗaya, mafi girman zurfin zaɓin ruwa na aperture aperture ya fi girma.

Sakamakon gwajin ya nuna cewa bai kamata a yi amfani da iska mai zurfi ba. A zurfin shigarwa na 2 m, ƙarar iska na 0.5 m3/h da na'urar aerator tare da girman rami na 200 μm ya haifar da matsakaicin ƙarfin ka'ida na 1.97 kg/(kW-h).