張 佳,邢 濤,孫永明,孔曉英,康溪輝,呂鵬梅,王春龍,李金平
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車用生物燃?xì)夤こ谭独酂岫吭u估及可利用性分析
張 佳1,2,3,4,5,邢 濤3,4,5,孫永明3,4,5※,孔曉英3,4,5,康溪輝3,4,5,呂鵬梅3,4,5,王春龍1,2,李金平1,2
(1. 蘭州理工大學(xué)西部能源與環(huán)境研究中心,蘭州730050; 2. 甘肅省生物質(zhì)能與太陽能互補供能系統(tǒng)重點實驗室,蘭州730050; 3. 中國科學(xué)院廣州能源研究所,廣州510640; 4. 中國科學(xué)院可再生能源重點實驗室,廣州510640;5. 廣東省新能源和可再生能源研究開發(fā)與應(yīng)用重點實驗室,廣州 510640)
針對車用生物燃?xì)夤こ棠芎母?、余熱利用率低的問題,該文以國內(nèi)4個典型工程為基礎(chǔ),構(gòu)建了產(chǎn)氣規(guī)模為1萬m3/d的示例工程,并對其進(jìn)行余熱分析。分析結(jié)果顯示,此類工程用能量大,占總產(chǎn)能的30.01%~36.44%;余熱利用率低,只有部分貧液余熱得以回收;系統(tǒng)余熱主要由脫碳塔頂氣余熱、脫碳貧液余熱、壓縮機(jī)余熱、沼液余熱和鍋爐尾氣余熱5部分組成,其多為低品位余熱、量大穩(wěn)定。余熱計算表明,在最冷月和最熱月系統(tǒng)余熱潛力分別為5.87×104、4.79×104MJ/d,最大節(jié)能潛力分別為74.81%和73.92%,節(jié)能潛力降序排列為沼液余熱>貧液余熱>塔頂氣余熱>壓縮機(jī)余熱>鍋爐余熱。余熱可利用性分析認(rèn)為工程余熱可利用性較高,回收價值較大。
燃?xì)猓粺崮?;生物質(zhì);余熱分析;余熱計算;節(jié)能潛力
車用生物燃?xì)?,是指有機(jī)廢棄物厭氧發(fā)酵產(chǎn)生的粗沼氣經(jīng)凈化、提純、壓縮達(dá)到車用標(biāo)準(zhǔn)的生物燃?xì)猓哂袩o污染、可再生和經(jīng)濟(jì)效益高等優(yōu)點[1-2]。近年來,中國有機(jī)廢棄物排放量增長迅速,資源化利用需求緊迫。與此同時,天然氣等清潔能源需求逐年增長,天然氣缺口較大。車用生物燃?xì)夤こ淘谔幚韽U棄物的同時,可產(chǎn)生清潔能源生物天然氣,已引起各界的重視[3-5]。沼氣發(fā)展“十三五”規(guī)劃指出制備生物天然氣是解決中國廢棄物處理和資源化利用問題的關(guān)鍵,計劃新建規(guī)?;锾烊粴忭椖?72個[6]。車用生物燃?xì)夤こ痰陌l(fā)展在一定程度上解決了許多地區(qū)的能源、環(huán)境及社會問題,但其運行過程仍存在系統(tǒng)能耗高和運行成本高的問題,提高工程余熱利用率可有效減少系統(tǒng)用能及成本的投入[7-9]。
車用生物燃?xì)夤こ桃话阋?guī)模較大,日產(chǎn)氣在1萬m3以上,工程的運行需消耗大量的熱能,伴隨也將產(chǎn)生許多的余熱,與其他沼氣工程相比,車用生物燃?xì)夤こ逃酂崃扛喔€(wěn)定[10-11]。目前,已有學(xué)者對沼氣工程余熱進(jìn)行分析計算;Zhang Xiaojing等[12]通過將沼氣生產(chǎn)系統(tǒng)和沼氣凈化系統(tǒng)的熱量進(jìn)行集成,得出回收余熱可滿足沼氣生產(chǎn)系統(tǒng)64%~100%的熱需求,沼氣凈產(chǎn)氣率提高5.3%~17.4%?;ㄧR等[13]分析回收瑞典Alviksgarden養(yǎng)豬場沼氣工程沼液50%的熱量,可滿足工程44.44%的熱需求,每年增產(chǎn)沼氣5.5×104m3。相關(guān)研究表明,生物燃?xì)夤こ逃酂釢摿Υ?,提高系統(tǒng)余熱利用率對工程節(jié)能減耗、降低成本和增強系統(tǒng)穩(wěn)定性具有重要的意義。但在已有研究中,針對整個車用生物燃?xì)夤こ踢M(jìn)行余熱分析的文獻(xiàn)較少。本文以國內(nèi)4個典型車用生物燃?xì)夤こ虨榛A(chǔ),構(gòu)建了產(chǎn)氣規(guī)模為1萬m3/d的示例工程,通過對其進(jìn)行余熱和需熱進(jìn)行統(tǒng)計,計算出系統(tǒng)余熱潛力和節(jié)能潛力,根據(jù)余熱特點,對系統(tǒng)余熱進(jìn)行可利用性評價,最后,結(jié)合需熱和余熱的特點為工程余熱利用提供建議。
車用生物燃?xì)夤こ藺位于山東,日處理混合原料700 t,日產(chǎn)沼氣7萬m3,車用生物燃?xì)?.2萬m3/d。工程采用主要技術(shù)包括混合原料厭氧發(fā)酵、中溫厭氧發(fā)酵技術(shù)、濕法催化脫硫、膜法脫碳、沼液沼渣制肥、四級壓縮技術(shù)等,主要技術(shù)指標(biāo)包括進(jìn)料濃度為8%,消化溫度為37 ℃,沼氣中CH4濃度為60%,車用生物燃?xì)庵蠧H4濃度>97%。工程調(diào)研可知,該工程主要余熱包括沼液余熱和壓縮機(jī)余熱。
車用生物燃?xì)夤こ藼位于海南,日處理混合原料500 t,日產(chǎn)沼氣3萬m3,車用生物燃?xì)?.65萬m3/d。工程采用主要技術(shù)包括混合原料厭氧發(fā)酵、中溫厭氧發(fā)酵技術(shù)、干法脫硫、高壓水洗法脫碳、沼液沼渣制肥、五級壓縮技術(shù)、鍋爐增溫等,主要技術(shù)指標(biāo)包括進(jìn)料濃度為10%,消化溫度為37 ℃,沼氣中CH4濃度為55%,車用生物燃?xì)庵蠧H4濃度>96%。該工程主要余熱包括沼液余熱、壓縮機(jī)余熱和鍋爐尾氣余熱。
車用生物燃?xì)夤こ藽位于山東,日處理有機(jī)廢水2萬m3,日產(chǎn)沼氣5萬m3,其中3萬m3沼氣發(fā)電,2萬m3沼氣制備1.26萬m3車用生物燃?xì)狻9こ滩捎弥饕夹g(shù)包括中溫厭氧發(fā)酵、濕法催化脫硫、醇胺法脫碳、四級壓縮技術(shù)、發(fā)電余熱和燃?xì)忮仩t增溫等,主要技術(shù)指標(biāo)包括進(jìn)料濃度為8%,消化溫度為37 ℃,COD去除率>90%,沼氣中CH4濃度為63%,車用生物燃?xì)庵蠧H4濃度>97%。該工程主要余熱包括沼液余熱、脫碳塔頂氣余熱、脫碳貧液余熱、壓縮機(jī)余熱、發(fā)電煙氣余熱、發(fā)電缸套水余熱和鍋爐尾氣余熱。
車用生物燃?xì)夤こ藾位于甘肅,日處理混合原料1 000 t,日產(chǎn)沼氣4萬m3,車用生物燃?xì)?.4萬m3/d。采用的主要技術(shù)包括高溫厭氧發(fā)酵、生物脫硫、醇胺法脫碳、沼液沼渣制肥、四級壓縮技術(shù)、鍋爐增溫等,主要技術(shù)指標(biāo)為進(jìn)料濃度為10%,消化溫度為55 ℃,沼氣中CH4濃度為60%,車用生物燃?xì)庵蠧H4濃度>97%。該工程主要余熱包括沼液余熱、脫碳塔頂氣余熱、脫碳貧液余熱、壓縮機(jī)余熱、鍋爐尾氣余熱。
分析A、B、C、D 4個典型工程可知,系統(tǒng)余熱主要由沼液余熱、塔頂氣余熱、貧液余熱、壓縮機(jī)余熱和鍋爐尾氣余熱5部分組成,以此為基礎(chǔ)建立日產(chǎn)氣為1萬m3的工程模型。
該系統(tǒng)模型位于山東,最冷月室外平均溫度為?5 ℃,最熱月室外平均溫度25 ℃;其發(fā)酵液最冷月平均溫度為15 ℃,最熱月平均溫度為25 ℃,數(shù)據(jù)來源于工程A和C。預(yù)處理模塊數(shù)據(jù)來源于工程A和B,通過攪拌等機(jī)械預(yù)處理方式處理混合原料120 t,混合原料的總固體含量(TS)為20%,勻漿調(diào)節(jié)后發(fā)酵液TS為10%。厭氧發(fā)酵模塊數(shù)據(jù)來源于工程A和D,預(yù)處理后的發(fā)酵液被加熱到55 ℃進(jìn)行高溫厭氧發(fā)酵,日產(chǎn)沼氣1萬m3,其中8 000 m3制備車用生物燃?xì)? 800 m3,2 000 m3用于供熱,4個2 500 m3厭氧發(fā)酵罐,其材料采用搪瓷鋼板,導(dǎo)熱系數(shù)1為0.047 W/(m2·℃),保溫層采用苯板,導(dǎo)熱系數(shù)2為1.51 W/(m2·℃)。凈化提純模塊數(shù)據(jù)來源于工程C,粗沼氣中CH4濃度為60%,凈化提純后CH4濃度高于97%,8 000 m3粗沼氣經(jīng)儲氣柜穩(wěn)壓后,首先進(jìn)行濕法催化脫硫并干燥,其次進(jìn)行醇胺法脫碳,吸收CO2溫度為40 ℃,解吸CO2溫度為120 ℃,乙醇胺溶液流量為8.9 m3/h,塔頂氣溫度為98 ℃。壓縮制氣模塊數(shù)據(jù)來源于工程C,采用四級壓縮將氣體壓縮至25 MPa,壓縮機(jī)冷卻水進(jìn)出口溫度分別為30和40 ℃。沼液沼渣后處理模塊數(shù)據(jù)來源于工程A,沼液制作葉面肥,沼渣制作生物肥,沼液溫度55 ℃。增溫保溫模塊數(shù)據(jù)來源于工程D,主要通過鍋爐供給,日消耗沼氣2 000 m3,產(chǎn)生煙氣流量為625 m3/h,煙氣溫度為180 ℃。
系統(tǒng)余熱主要包含脫碳塔頂氣余熱、貧液余熱、壓縮機(jī)冷卻水余熱、沼液余熱和鍋爐尾氣余熱,系統(tǒng)需熱主要包含發(fā)酵液升溫需熱、維持高溫發(fā)酵需熱和脫碳解吸需熱。其系統(tǒng)流程圖如圖1所示。
圖1 車用生物燃?xì)夤こ滔到y(tǒng)流程圖
1)發(fā)酵液需熱計算公式為
其中C計算公式[12]為
式中T為發(fā)酵液總固體含量。
2)熱損失需熱計算公式[16-18]為
3)醇胺法脫碳需熱計算公式[19]為
4)系統(tǒng)總需熱計算公式為
式中Q系統(tǒng)總需熱量,MJ/d;下同。
計算結(jié)果如表1所示,其中在最冷月和最熱月系統(tǒng)總需熱分別為7.85×104和6.48×104MJ/d。
表1 系統(tǒng)需熱
注:沼氣熱值為21.54 MJ。
Note: The heat value of biogas is 21.54 MJ.
2.2.1 余熱資源統(tǒng)計分析
余熱資源統(tǒng)計的主要信息包括余熱來源、余熱介質(zhì)及其特性、溫度、流量和余熱特點等,系統(tǒng)余熱資源統(tǒng)計結(jié)果如表2。
表2 系統(tǒng)余熱
注:脫碳單元與壓縮單元每天運行14 h,發(fā)酵液每隔3 h進(jìn)1 h料,增溫保溫單元24 h運行。
Note: Decarburization unit and compression unit run 14 h per day, biogas slurry is pumped for 1 h every 3 h, warming and heat insulation unit runs 24 h per day.
2.2.2 余熱潛力及節(jié)能潛力計算
由國標(biāo)GB/T 1028-2000知[22],余熱潛力的計算方法為
系統(tǒng)總余熱潛力計算如下
式中Q為總余熱潛力,1為塔頂氣余熱,2為貧液余熱,3為壓縮機(jī)余熱,4為沼液余熱,5為鍋爐余熱,單位均為kJ/d。
余熱節(jié)能潛力的計算方法為
式中η為余熱節(jié)能潛力,其中=1,2,3…,為自然數(shù)。
余熱潛力計算結(jié)果如表3所示。
表3 余熱潛力計算結(jié)果
計算得最冷月和最熱月總余熱潛力Q分別為5.87×104和4.79×104MJ/d。
由余熱節(jié)能潛力計算得,在最冷月和最熱月,系統(tǒng)最大節(jié)能潛力η分別為74.81%、73.92%;塔頂氣余熱節(jié)能潛力1分別為5.27%、6.39%;貧液余熱節(jié)能潛力2分別為14.65%、17.75%;壓縮機(jī)節(jié)能潛力3分別為3.08%、3.67%;沼液余熱節(jié)能潛力4分別為46.75%、42.44%;鍋爐余熱節(jié)能潛力5分別為5.06%、3.73%。5部分余熱潛力占比如圖2所示。
a. 最冷月余熱節(jié)能潛力占比
a. Ratio of energy-saving potential of waste heat in coldest month
b. 最熱月余熱節(jié)能潛力占比
由圖2可知,沼液余熱節(jié)能潛力最大,占總余熱的50%以上,應(yīng)重點回收,同濟(jì)大學(xué)裴曉梅利用熱泵技術(shù)回收沼液余熱,結(jié)果表明沼液余熱節(jié)能潛力可達(dá)70%,揭示了沼液余熱回收巨大價值和可行性[26]。貧液余熱次之,占總余熱的20%左右,余熱價值較大。塔頂氣余熱、壓縮機(jī)冷卻水余熱、鍋爐尾氣余熱雖然所占比例相對較小,但其均位于系統(tǒng)末端,冷卻水與鍋爐尾氣余熱利用技術(shù)較成熟,其余熱仍有一定回收價值。北京化工大學(xué)張克舫對年產(chǎn)100萬t CO2的醇胺法脫碳系統(tǒng)進(jìn)行能量計算,得出其貧液和塔頂氣余熱量分別為7.42×106和5.58×106MJ/d,并分析了其利用途徑,貧液余熱可以通過擴(kuò)大貧富液換熱器的面積得到更多的回收,塔頂氣余熱可通過第二類吸收式熱泵加熱解吸塔內(nèi)富液[23]。Kostowsk通過計算驗證了回收車用生物燃?xì)饧託庹緣嚎s機(jī)余熱回收的可行性,并對系統(tǒng)余熱利用進(jìn)行優(yōu)化,優(yōu)化后增強了系統(tǒng)的穩(wěn)定性[27]。Lee等對比分析了冷凝式余熱鍋爐的熱效率,結(jié)果顯示冷凝式余熱鍋爐可以把煙氣溫度降到50~60 ℃,比普通燃?xì)忮仩t熱效率高7.04%[28]。系統(tǒng)余熱節(jié)能潛力按大小降序排列為:沼液余熱>貧液余熱>塔頂氣余熱>壓縮機(jī)余熱>鍋爐余熱。
2.3.1 余熱可利用性
1)塔頂氣余熱
塔頂氣余熱的介質(zhì)主要為CO2和水蒸汽,具有弱酸性,溫度為98 ℃,余熱節(jié)能潛力為5.27%~6.39%,該余熱產(chǎn)生于解吸塔頂出口,屬于末端環(huán)節(jié),98 ℃塔頂氣可用來加熱物料,與系統(tǒng)需熱匹配,余熱回收價值一般,可利用性較高。對于塔頂氣余熱,可利用熱交換、熱泵技術(shù)和余熱制冷回收余熱,考慮到系統(tǒng)需熱和傳輸距離,建議利用換熱器加熱低溫富液或利用熱泵生產(chǎn)蒸汽回用于系統(tǒng)自身。
2)貧液余熱
貧液余熱的介質(zhì)為醇胺溶液,具有弱堿性,溫度為69 ℃,余熱節(jié)能潛力為14.65%~17.75%,該余熱產(chǎn)生于貧富液換熱器的出口,屬于中間環(huán)節(jié),69 ℃的貧液仍可用來加熱低溫富液,與系統(tǒng)匹配,余熱回收價值較高,可利用性較高。對于貧液余熱,可利用的技術(shù)包括熱交換和熱泵技術(shù),考慮余熱的特點和經(jīng)濟(jì)性,建議利用換熱器加熱低溫醇胺富液。
3)壓縮機(jī)冷卻水余熱
壓縮機(jī)冷卻水余熱的介質(zhì)為冷卻水,溫度為40 ℃,余熱節(jié)能潛力3.67%~5.06%,該余熱產(chǎn)生于壓縮機(jī)系統(tǒng)末端,屬于末端環(huán)節(jié),40 ℃的冷卻水與系統(tǒng)需熱不匹配,余熱有一定回收價值,可利用性一般。壓縮機(jī)排氣冷卻水余熱,雖品味較低,但數(shù)量較大,建議利用熱泵生產(chǎn)供暖或生活熱水。
4)沼液余熱
沼液余熱的介質(zhì)為沼液,具有黏滯性,溫度為55 ℃,余熱節(jié)能潛力為42.44%~46.75%,該余熱產(chǎn)生于固液分離末端,屬于末端環(huán)節(jié),與需熱匹配可用來加熱發(fā)酵液,回收價值高,余熱可利用性較高。沼液余熱可利用熱交換或熱泵技術(shù)進(jìn)行熱回收,建議用換熱器或熱泵加熱低溫發(fā)酵液。
5)鍋爐尾氣余熱
鍋爐余熱的介質(zhì)為煙氣,具有弱酸性,溫度為180 ℃,余熱節(jié)能潛力為3.08%~3.73%,該余熱產(chǎn)生于鍋爐排氣口,屬于末端環(huán)節(jié),可用來加熱原料,余熱有一定回收價值,可利用性較高。鍋爐尾氣余熱溫度高、余熱利用技術(shù)成熟,可利用的技術(shù)有熱交換、熱泵技術(shù)和余熱制冷,考慮到系統(tǒng)需熱,建議直接通過換熱器生產(chǎn)蒸汽或熱水回用于系統(tǒng)。
2.3.2 余熱可利用評價及建議
系統(tǒng)余熱可利用性可采用五星級體系評價,評價指標(biāo)包括:余熱介質(zhì),余熱溫度,余熱數(shù)量,中間環(huán)節(jié)或末端環(huán)節(jié),是否與系統(tǒng)需熱匹配。
余熱可利用性判別指標(biāo)體系:1)余熱介質(zhì)是否存在黏滯性、腐蝕性、酸堿性,存在為“—”,不存在為“★”;2)余熱溫度是否高于沼液溫度,低于沼液溫度為“—”,高于沼液溫度為“★”;3)余熱數(shù)量是否大于總余熱的10%,小于為“—”,大于為“★”;4)余熱產(chǎn)生于中間環(huán)節(jié)為“—”,產(chǎn)生于末端環(huán)節(jié)為“★”;5)與需熱不匹配為“—”,與需熱匹配為“★”。系統(tǒng)總余熱的可利用性將通過5個指標(biāo)的平均“★”數(shù)判定。
如表4所示,系統(tǒng)余熱可利用性較高,回收價值較大。系統(tǒng)余熱利用建議如圖3。
表4 余熱可利用性評價
注:“★”代表優(yōu)勢,“—”代表劣勢;五顆星代表極高,四顆星代表高,三顆星代表較高,兩顆星代表一般,一顆星代表低。
Note: “★” represent advantage, “—” represent disadvantage, five stars represent extremely high, four stars represent high, three stars represent relatively high, two stars represent common, one star represents low.
圖3 余熱潛在利用途徑
1)該車用生物燃?xì)夤こ绦锜崃空脊こ炭偖a(chǎn)能的30.01%~36.44%,用能較多;余熱利用率低,只有部分貧液余熱得以回收;系統(tǒng)余熱主要由脫碳塔頂氣余熱、貧液余熱、壓縮機(jī)排氣冷卻水余熱、沼液余熱和鍋爐尾氣余熱五部分組成。
2)系統(tǒng)最冷月和最熱月總余熱潛力分別為5.87×104MJ/d、4.79×104MJ/d,分別占總需熱的74.8%和73.9%。其中沼液和貧液余熱節(jié)能潛力較大,約占總節(jié)能潛力的80%左右。
3)余熱可利用性分析指出系統(tǒng)余熱可利用性較高,回收價值較大。建議塔頂氣余熱利用熱泵技術(shù)生產(chǎn)蒸汽或熱水,貧液余熱利用換熱器加熱富液,壓縮機(jī)冷卻水余熱升級生產(chǎn)熱水,沼液余熱利用高效換熱器加熱發(fā)酵液,鍋爐余熱利用換熱器或熱管生產(chǎn)蒸汽。
當(dāng)前系統(tǒng)余熱潛力大,但余熱利用效率低,重要原因是余熱品味較低,開發(fā)低品位余熱利用技術(shù)是下一步研究的重點。另外,系統(tǒng)存在多種余熱和需熱,如何將系統(tǒng)多種余熱和需熱相互匹配,從自身減少加熱公用工程量和冷卻工程量仍有待進(jìn)一步研究。
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Quantitive estimation and availability analysis of waste heat from vehicle biogas plant
Zhang Jia1,2,3,4,5, Xing Tao3,4,5, Sun Yongming3,4,5※, Kong Xiaoying3,4,5, Kang Xihui3,4,5, Lü Pengmei3,4,5, Wang Chunlong1,2, Li Jinping1,2
(1.,,730050,;2.,730050,;3.,,510640,; 4.510640,;5.,510640,)
Vehicle biogas, the product deriving from the organic waste anaerobic digestion accompanying with the purification and compression process, has the advantages of higher energy efficiency, environmentally friendliness, sustainability, and so on. The vehicle biogas plant has aroused attention from all walks of life and owned a broad prospect, because it can not only dispose organic waste, but also produce clean vehicle biogas. However, there were still several problems in its operation process, such as high operating costs, high energy consumption and low utilization rate of waste heat. In order to solve these problems, this paper establishes a model of vehicle biogas plant which produces 10 000 m3biogas daily. We firstly introduce the general situation of this model and calculate the potential of waste heat. What’s more, the availability of waste heat is evaluated. Finally, combined with the requirement of heat, the suggestion of the waste heat utilization is put forward. Results of analysis show that this plant needs a lot of thermal energy, approximately accounting for 30.01%-36.44% of biogas energy. Moreover, merely recycling a part of the CO2-poor MEA liquid waste heat after decarburization results in low utilization rate of waste heat. It also reveals that the main parts of the waste heat in the system are made up of 5 types, i.e. waste heat from stripper top gas for decarburization, CO2-poor MEA liquid waste heat after decarburization, waste heat of cooling water from compressor, waste heat in biogas slurry and waste heat of boiler exhaust gas. Besides, the low-grade waste heat has the characteristics of enormous quantity and stabilization. The main parts of heat required include the heat of the fermentation liquid, the heat of maintaining high-temperature anaerobic digestion and the heat of decarburization. The calculation of requirement of heat shows that the quantity of total heat required is 7.85×104MJ/d in the coldest month, and 6.48×104MJ/d in the hottest month. The calculation of waste heat indicates that the potential of total waste heat is respectively 5.87×104MJ/d in the coldest month, and 4.79×104MJ/d in the hottest month. The corresponding maximum energy-saving rate is 74.81% and 73.92%, respectively. The energy-saving potential of each part of waste heat in descending order of quantity is: waste heat of biogas slurry > waste heat of CO2-poor MEA liquid after decarburization > waste heat of stripper top gas for decarburization > waste heat of cooling water from compressor > waste heat of boiler exhaust gas. Additionally, the analysis of waste heat proves that waste heat from this project can be more effectively utilized and preferably collected. Based on the analysis above, we propose some suggestions about the utilization of waste heat: 1) It is recommended that the waste heat of stripper top gas is collected to drive heat pump rather than cycle in system. 2) Waste heat of CO2-poor MEA liquid can be used to warm the low-temperature CO2-rich MEA liquid via the heat exchanger. 3) We recommend the waste heat of compressor cooling water is adopted to produce hot water by the heat pump, which will be regarded as domestic hot water or heating hot water. 4) Waste heat of biogas slurry can be used to heat low-temperature fermentation liquid by heat exchanger. 5) Waste heat of boiler exhaust gas can produce stream by heat exchanger, which is applied into system itself.
gas; thermal energy; biomass; analysis of waste heat; calculation of waste heat; potential of energy-saving
10.11975/j.issn.1002-6819.2017.17.031
TK11
A
1002-6819(2017)-17-0232-07
2017-04-12
2017-08-21
國家科技支撐(2015BAD21B03);國家“863”計劃課題(2014AA052801);廣東省科技計劃項目(2015B020215011);中科院技術(shù)服務(wù)網(wǎng)絡(luò)計劃(KFJ-Ew-STS-138)
張 佳,主要從事余熱利用方向研究。蘭州 蘭州理工大學(xué)西部能源與環(huán)境研究中心,730050。Email:527111124@qq.com
孫永明,博士,研究員,主要從事生物質(zhì)生化轉(zhuǎn)化研究。廣州 中國科學(xué)院廣州能源研究所,510640。Email:sunym@ms.giec.ac.cn