一、供熱系統與介質
集(ji)(ji)(ji)中(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)是(shi)指一個或(huo)多個集(ji)(ji)(ji)中(zhong)的(de)(de)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)，通過供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)管網向多個熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶供(gong)(gong)(gong)(gong)應熱(re)(re)(re)(re)(re)(re)(re)(re)(re)能(neng)的(de)(de)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)，它主要由熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)、熱(re)(re)(re)(re)(re)(re)(re)(re)(re)網和熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶組成。其(qi)中(zhong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)是(shi)指將天然(ran)或(huo)人(ren)造(zao)的(de)(de)能(neng)源(yuan)(yuan)(yuan)(yuan)形態(tai)轉(zhuan)化(hua)為符合供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)要求(qiu)的(de)(de)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)能(neng)裝置。熱(re)(re)(re)(re)(re)(re)(re)(re)(re)網是(shi)指由熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)向熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶輸送和分(fen)配供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)介質的(de)(de)管道系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)，熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶是(shi)指從熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)獲得熱(re)(re)(re)(re)(re)(re)(re)(re)(re)能(neng)的(de)(de)用熱(re)(re)(re)(re)(re)(re)(re)(re)(re)裝置。集(ji)(ji)(ji)中(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)分(fen)類(lei)方式(shi)有三(san)種(zhong)，可以根據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)分(fen)類(lei)、根據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)媒分(fen)類(lei)、根據供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)管網分(fen)類(lei)。集(ji)(ji)(ji)中(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)按(an)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)(yuan)形式(shi)的(de)(de)不(bu)同可分(fen)為：熱(re)(re)(re)(re)(re)(re)(re)(re)(re)電廠供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)、區域鍋爐(lu)房供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)、地熱(re)(re)(re)(re)(re)(re)(re)(re)(re)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)、工(gong)業余熱(re)(re)(re)(re)(re)(re)(re)(re)(re)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)、核供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)堆和太陽能(neng)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)等。集(ji)(ji)(ji)中(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)根據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)媒不(bu)同分(fen)為蒸汽供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)和熱(re)(re)(re)(re)(re)(re)(re)(re)(re)水供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)(tong)(tong)。
熱水(shui)熱力(li)(li)(li)網供(gong)熱介質設(she)計壓力(li)(li)(li)小于(yu)或(huo)(huo)等(deng)于(yu)2.5MPa，設(she)計溫(wen)度(du)小于(yu)或(huo)(huo)等(deng)于(yu)200℃；蒸汽熱力(li)(li)(li)網供(gong)熱介質設(she)計壓力(li)(li)(li)小于(yu)或(huo)(huo)等(deng)于(yu)1.6MPa，設(she)計溫(wen)度(du)小于(yu)或(huo)(huo)等(deng)于(yu)350℃。
對民用建筑物采暖、通風、空調及生(sheng)活熱水熱負荷(he)供熱的城(cheng)市熱力網，宜采用水作供熱介質。
對(dui)生(sheng)產工藝(yi)熱(re)(re)負(fu)荷(he)(he)(he)和采(cai)暖、通(tong)風(feng)(feng)、空(kong)調、生(sheng)活熱(re)(re)水(shui)(shui)熱(re)(re)負(fu)荷(he)(he)(he)供(gong)熱(re)(re)的城市熱(re)(re)力網供(gong)熱(re)(re)介質(zhi)(zhi)按下列原則(ze)確定：當(dang)(dang)生(sheng)產工藝(yi)熱(re)(re)負(fu)荷(he)(he)(he)為主(zhu)要負(fu)荷(he)(he)(he)，且(qie)必(bi)須采(cai)用(yong)蒸(zheng)汽(qi)供(gong)熱(re)(re)時(shi)(shi)，宜采(cai)用(yong)蒸(zheng)汽(qi)作供(gong)熱(re)(re)介質(zhi)(zhi)；當(dang)(dang)以水(shui)(shui)位供(gong)熱(re)(re)介質(zhi)(zhi)能夠滿足生(sheng)產工藝(yi)需要（包括(kuo)在用(yong)戶處(chu)轉(zhuan)換為蒸(zheng)汽(qi)），且(qie)技(ji)術(shu)經(jing)濟合理(li)時(shi)(shi)，宜采(cai)用(yong)水(shui)(shui)作供(gong)熱(re)(re)介質(zhi)(zhi)；當(dang)(dang)采(cai)暖、通(tong)風(feng)(feng)、空(kong)調熱(re)(re)負(fu)荷(he)(he)(he)為主(zhu)要負(fu)荷(he)(he)(he)，生(sheng)產工藝(yi)又必(bi)須采(cai)用(yong)蒸(zheng)汽(qi)供(gong)熱(re)(re)，經(jing)技(ji)術(shu)經(jing)濟比(bi)較認為合理(li)時(shi)(shi)，可采(cai)用(yong)水(shui)(shui)和蒸(zheng)汽(qi)兩種供(gong)熱(re)(re)介質(zhi)(zhi)。
1. 國家現行(xing)標準(zhun)GJJ／T 34《城(cheng)鎮供(gong)熱(re)(re)管(guan)網(wang)(wang)設(she)計(ji)(ji)規范》適用于(yu)供(gong)熱(re)(re)熱(re)(re)水介(jie)質設(she)計(ji)(ji)壓(ya)(ya)力(li)(li)小(xiao)(xiao)于(yu)或(huo)等于(yu)2.5MPa，設(she)計(ji)(ji)溫(wen)度小(xiao)(xiao)于(yu)或(huo)等于(yu)200℃；供(gong)熱(re)(re)蒸汽介(jie)質設(she)計(ji)(ji)壓(ya)(ya)力(li)(li)小(xiao)(xiao)于(yu)或(huo)等于(yu)1.6MPa，設(she)計(ji)(ji)溫(wen)度小(xiao)(xiao)于(yu)或(huo)等于(yu)350℃的下列城(cheng)鎮供(gong)熱(re)(re)管(guan)網(wang)(wang)的設(she)計(ji)(ji)：以(yi)熱(re)(re)電廠或(huo)鍋(guo)爐房為熱(re)(re)源，自熱(re)(re)切至建(jian)筑物熱(re)(re)力(li)(li)人口(kou)的供(gong)熱(re)(re)管(guan)網(wang)(wang)，供(gong)熱(re)(re)管(guan)網(wang)(wang)新(xin)建(jian)、擴建(jian)或(huo)改建(jian)的管(guan)道、中斷泵站(zhan)和熱(re)(re)力(li)(li)站(zhan)等工藝系統。
2. 國家現行標準(zhun)GJJ／T 81《城(cheng)鎮(zhen)供熱(re)直(zhi)埋熱(re)水(shui)管(guan)(guan)道(dao)技術規(gui)程》適用于(yu)新(xin)建、改建、擴(kuo)建的設(she)計(ji)溫(wen)度小(xiao)(xiao)于(yu)或(huo)等于(yu)150℃、設(she)計(ji)壓力小(xiao)(xiao)于(yu)或(huo)等于(yu)2.5MPa，DN小(xiao)(xiao)于(yu)或(huo)等于(yu)1200mm的城(cheng)鎮(zhen)供熱(re)直(zhi)埋熱(re)水(shui)管(guan)(guan)道(dao)的設(she)計(ji)、施工、驗收和(he)運行管(guan)(guan)理。
3. 國家現(xian)行標準(zhun)GJJ／T 104《城鎮供熱直(zhi)埋(mai)蒸汽(qi)(qi)管(guan)道技術規程(cheng)》適用(yong)于(yu)(yu)工(gong)作壓力小(xiao)于(yu)(yu)或等于(yu)(yu)2.5MPa，溫(wen)度小(xiao)于(yu)(yu)或等于(yu)(yu)350℃，直(zhi)接埋(mai)地敷設的(de)鋼質外(wai)護蒸汽(qi)(qi)保溫(wen)管(guan)道的(de)設計、施(shi)工(gong)、驗(yan)收及運行維護。
二、熱力網的形式(shi)
供熱管(guan)網(wang)按其平面布(bu)置(zhi)形(xing)式可分為枝(zhi)狀管(guan)網(wang)、環狀管(guan)網(wang)和(he)多管(guan)制(zhi)管(guan)網(wang)。其特點是：
1. 枝狀管(guan)網
從熱(re)源引(yin)出主干線(xian)(xian)沿城鎮道路向各熱(re)用(yong)戶供熱(re)，形成類似樹枝狀(zhuang)(zhuang)的管(guan)(guan)網叫枝狀(zhuang)(zhuang)管(guan)(guan)網。枝狀(zhuang)(zhuang)管(guan)(guan)網是(shi)目前我(wo)國城鎮供熱(re)中普遍采用(yong)的形式(shi)，它形式(shi)簡單、投(tou)資費用(yong)低，且運(yun)行管(guan)(guan)理(li)方便(bian)，但安全可靠(kao)性較差，當(dang)管(guan)(guan)網中距離熱(re)源較近的主干線(xian)(xian)發生故障時，會影響較多的熱(re)用(yong)戶用(yong)熱(re)。
2. 環狀(zhuang)管網(wang)
供熱(re)管(guan)網的主干(gan)線之間在適(shi)當位(wei)置連(lian)通(tong)構成環(huan)(huan)形(xing)，環(huan)(huan)狀管(guan)網運(yun)行較(jiao)安(an)全可靠，局部發生故障可通(tong)過環(huan)(huan)網供熱(re)。但投資(zi)費用高。
3. 多管制管網
一般用(yong)于以下情(qing)況：不能間斷的熱(re)(re)用(yong)戶；供熱(re)(re)系統中熱(re)(re)用(yong)戶所需介(jie)質參數差別(bie)較大；熱(re)(re)負荷變化(hua)較大：季節性熱(re)(re)負荷占全年(nian)總負荷比(bi)例(li)較大。
三(san)、熱水熱力網形式的確定
熱(re)(re)水(shui)熱(re)(re)力網宜采用(yong)閉(bi)(bi)式(shi)雙管制。以熱(re)(re)電廠為熱(re)(re)源的熱(re)(re)水(shui)熱(re)(re)力網，同時有工(gong)藝(yi)、采暖(nuan)、通風(feng)、空調(diao)、生(sheng)活熱(re)(re)水(shui)多種熱(re)(re)負(fu)荷(he)(he)，在生(sheng)產工(gong)藝(yi)熱(re)(re)負(fu)荷(he)(he)與采暖(nuan)熱(re)(re)負(fu)荷(he)(he)所需供熱(re)(re)介質參數相差較大(da)，或季(ji)節性熱(re)(re)負(fu)荷(he)(he)占總(zong)熱(re)(re)負(fu)荷(he)(he)比(bi)例較大(da)，且技術經濟合理時，可采用(yong)閉(bi)(bi)式(shi)多管制。
當(dang)熱(re)水熱(re)力網具有水處(chu)理費用(yong)較低的豐富的補給水資(zi)源，且技(ji)術經(jing)濟合理時，可采用(yong)開式熱(re)力網。
當(dang)熱(re)水熱(re)力網具有(you)與生活熱(re)水熱(re)負荷相適應的(de)廉價(jia)低位(wei)能熱(re)源，且(qie)技(ji)術(shu)經(jing)濟合理時(shi)，可(ke)采(cai)用開(kai)式熱(re)水網。
開(kai)式(shi)熱(re)(re)水熱(re)(re)力網在生活(huo)熱(re)(re)水熱(re)(re)負(fu)荷足夠大且技術經濟合理(li)時，可(ke)不(bu)設回(hui)水管。
四(si)、蒸汽熱力網形(xing)式的確定
蒸汽(qi)(qi)熱力(li)網宜采用(yong)單管(guan)(guan)制。當各用(yong)戶間所需蒸汽(qi)(qi)參數相差較(jiao)(jiao)大或季節(jie)性熱負荷占總熱負荷比例較(jiao)(jiao)大且技術經(jing)濟合理時，蒸汽(qi)(qi)熱力(li)網可采用(yong)雙管(guan)(guan)或多管(guan)(guan)制。
蒸(zheng)汽(qi)熱(re)力網的(de)熱(re)負荷(he)分(fen)期增長時，可采(cai)用(yong)雙(shuang)管(guan)或(huo)多管(guan)制(zhi)。蒸(zheng)汽(qi)供熱(re)系(xi)統應(ying)創(chuang)造條件采(cai)用(yong)間接換(huan)熱(re)系(xi)統。當被加熱(re)介質泄漏不會產(chan)生(sheng)危害時，其凝結水應(ying)全部回收并(bing)設置(zhi)凝結水管(guan)道。
當凝結水(shui)回收時，用戶熱(re)力站應設閉式(shi)凝結水(shui)箱，用水(shui)泵將凝結水(shui)送(song)回熱(re)源(yuan)。
五(wu)、多供熱(re)源熱(re)力網形(xing)式的確定
供熱建筑面積大于1000×104㎡的供熱系統應采用多熱源供熱，且各熱源熱力干線應連通。在技術經濟合理時，熱力網干線可連接成環狀管網。對供熱可靠性有特殊要求的用戶，有條件時應由兩個熱源供熱，或者設自備熱源。
