一、供熱系統與介質
集(ji)(ji)中(zhong)(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)是指(zhi)一個或多(duo)(duo)個集(ji)(ji)中(zhong)(zhong)的(de)(de)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)，通(tong)過供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)管網(wang)(wang)向(xiang)多(duo)(duo)個熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶(hu)(hu)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)，它主要(yao)由熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)、熱(re)(re)(re)(re)(re)(re)(re)(re)(re)網(wang)(wang)和熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶(hu)(hu)組成。其中(zhong)(zhong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)是指(zhi)將天然或人造的(de)(de)能(neng)源(yuan)(yuan)(yuan)形(xing)態轉化為(wei)符合(he)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)要(yao)求(qiu)的(de)(de)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)能(neng)裝(zhuang)置。熱(re)(re)(re)(re)(re)(re)(re)(re)(re)網(wang)(wang)是指(zhi)由熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)向(xiang)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶(hu)(hu)輸送(song)和分(fen)配供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)介(jie)質的(de)(de)管道系(xi)(xi)(xi)統(tong)(tong)(tong)，熱(re)(re)(re)(re)(re)(re)(re)(re)(re)用戶(hu)(hu)是指(zhi)從熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(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(zhuang)置。集(ji)(ji)中(zhong)(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)分(fen)類方式(shi)有三種(zhong)，可以根(gen)據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)分(fen)類、根(gen)據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)媒分(fen)類、根(gen)據供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)管網(wang)(wang)分(fen)類。集(ji)(ji)中(zhong)(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)按(an)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)源(yuan)(yuan)(yuan)形(xing)式(shi)的(de)(de)不(bu)同可分(fen)為(wei)：熱(re)(re)(re)(re)(re)(re)(re)(re)(re)電廠(chang)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(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)、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)、工業余熱(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)、核(he)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)堆和太陽(yang)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)等。集(ji)(ji)中(zhong)(zhong)供(gong)(gong)(gong)(gong)熱(re)(re)(re)(re)(re)(re)(re)(re)(re)系(xi)(xi)(xi)統(tong)(tong)(tong)根(gen)據熱(re)(re)(re)(re)(re)(re)(re)(re)(re)媒不(bu)同分(fen)為(wei)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)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)。
熱(re)(re)水熱(re)(re)力(li)網供熱(re)(re)介質設(she)計(ji)(ji)壓力(li)小于(yu)或等(deng)于(yu)2.5MPa，設(she)計(ji)(ji)溫(wen)度小于(yu)或等(deng)于(yu)200℃；蒸汽熱(re)(re)力(li)網供熱(re)(re)介質設(she)計(ji)(ji)壓力(li)小于(yu)或等(deng)于(yu)1.6MPa，設(she)計(ji)(ji)溫(wen)度小于(yu)或等(deng)于(yu)350℃。
對民用建筑物采暖、通風、空調(diao)及(ji)生活熱(re)(re)水熱(re)(re)負荷供熱(re)(re)的城市(shi)熱(re)(re)力網，宜(yi)采用水作供熱(re)(re)介(jie)質。
對生(sheng)(sheng)產工藝(yi)(yi)熱(re)負(fu)荷(he)和(he)采(cai)(cai)(cai)暖、通風、空調(diao)、生(sheng)(sheng)活熱(re)水(shui)(shui)熱(re)負(fu)荷(he)供(gong)熱(re)的城市熱(re)力網供(gong)熱(re)介(jie)質(zhi)按下列原(yuan)則(ze)確(que)定：當(dang)生(sheng)(sheng)產工藝(yi)(yi)熱(re)負(fu)荷(he)為(wei)主要負(fu)荷(he)，且必(bi)須采(cai)(cai)(cai)用蒸(zheng)(zheng)汽(qi)供(gong)熱(re)時，宜采(cai)(cai)(cai)用蒸(zheng)(zheng)汽(qi)作(zuo)供(gong)熱(re)介(jie)質(zhi)；當(dang)以(yi)水(shui)(shui)位(wei)供(gong)熱(re)介(jie)質(zhi)能夠(gou)滿足(zu)生(sheng)(sheng)產工藝(yi)(yi)需要（包括在用戶處轉換為(wei)蒸(zheng)(zheng)汽(qi)），且技術經濟(ji)合理(li)時，宜采(cai)(cai)(cai)用水(shui)(shui)作(zuo)供(gong)熱(re)介(jie)質(zhi)；當(dang)采(cai)(cai)(cai)暖、通風、空調(diao)熱(re)負(fu)荷(he)為(wei)主要負(fu)荷(he)，生(sheng)(sheng)產工藝(yi)(yi)又必(bi)須采(cai)(cai)(cai)用蒸(zheng)(zheng)汽(qi)供(gong)熱(re)，經技術經濟(ji)比較認為(wei)合理(li)時，可采(cai)(cai)(cai)用水(shui)(shui)和(he)蒸(zheng)(zheng)汽(qi)兩(liang)種供(gong)熱(re)介(jie)質(zhi)。
1. 國家現行(xing)標準GJJ／T 34《城鎮供(gong)(gong)熱(re)(re)(re)管(guan)(guan)網(wang)設計(ji)規(gui)范》適用于(yu)(yu)供(gong)(gong)熱(re)(re)(re)熱(re)(re)(re)水介(jie)質(zhi)(zhi)設計(ji)壓力(li)小(xiao)于(yu)(yu)或(huo)等(deng)(deng)于(yu)(yu)2.5MPa，設計(ji)溫度小(xiao)于(yu)(yu)或(huo)等(deng)(deng)于(yu)(yu)200℃；供(gong)(gong)熱(re)(re)(re)蒸汽介(jie)質(zhi)(zhi)設計(ji)壓力(li)小(xiao)于(yu)(yu)或(huo)等(deng)(deng)于(yu)(yu)1.6MPa，設計(ji)溫度小(xiao)于(yu)(yu)或(huo)等(deng)(deng)于(yu)(yu)350℃的下列城鎮供(gong)(gong)熱(re)(re)(re)管(guan)(guan)網(wang)的設計(ji)：以熱(re)(re)(re)電廠或(huo)鍋爐房為熱(re)(re)(re)源，自熱(re)(re)(re)切至建(jian)(jian)筑(zhu)物(wu)熱(re)(re)(re)力(li)人口的供(gong)(gong)熱(re)(re)(re)管(guan)(guan)網(wang)，供(gong)(gong)熱(re)(re)(re)管(guan)(guan)網(wang)新(xin)建(jian)(jian)、擴建(jian)(jian)或(huo)改建(jian)(jian)的管(guan)(guan)道、中斷(duan)泵站和熱(re)(re)(re)力(li)站等(deng)(deng)工藝系統。
2. 國家(jia)現(xian)行(xing)標準GJJ／T 81《城(cheng)鎮供熱(re)直埋(mai)熱(re)水管(guan)(guan)道技術規程(cheng)》適用(yong)于(yu)新建、改建、擴建的(de)設計溫(wen)度(du)小于(yu)或等于(yu)150℃、設計壓力小于(yu)或等于(yu)2.5MPa，DN小于(yu)或等于(yu)1200mm的(de)城(cheng)鎮供熱(re)直埋(mai)熱(re)水管(guan)(guan)道的(de)設計、施工、驗(yan)收和運行(xing)管(guan)(guan)理。
3. 國家現行標(biao)準GJJ／T 104《城鎮(zhen)供熱直埋(mai)蒸汽(qi)管道技術規程(cheng)》適(shi)用于(yu)工(gong)作壓力小于(yu)或(huo)等于(yu)2.5MPa，溫度小于(yu)或(huo)等于(yu)350℃，直接埋(mai)地敷(fu)設的鋼質(zhi)外護(hu)蒸汽(qi)保溫管道的設計、施工(gong)、驗收及運行維護(hu)。
二、熱力網的形式
供熱管(guan)網(wang)按其平面(mian)布置形(xing)式可分為(wei)枝狀管(guan)網(wang)、環狀管(guan)網(wang)和多管(guan)制管(guan)網(wang)。其特點是：
1. 枝(zhi)狀管網(wang)
從熱(re)(re)源引(yin)出主干(gan)線(xian)(xian)沿城(cheng)鎮道路向各(ge)熱(re)(re)用(yong)戶供(gong)熱(re)(re)，形(xing)成類似樹枝(zhi)狀的(de)管網叫枝(zhi)狀管網。枝(zhi)狀管網是目(mu)前我國城(cheng)鎮供(gong)熱(re)(re)中普遍采用(yong)的(de)形(xing)式，它形(xing)式簡單、投資費用(yong)低(di)，且運(yun)行管理方便，但安全可(ke)靠(kao)性較差，當管網中距離熱(re)(re)源較近的(de)主干(gan)線(xian)(xian)發生故障(zhang)時，會影(ying)響較多(duo)的(de)熱(re)(re)用(yong)戶用(yong)熱(re)(re)。
2. 環(huan)狀管網
供熱(re)管網(wang)的(de)主干線之(zhi)間在(zai)適當位置連通構(gou)成環形，環狀管網(wang)運行(xing)較安全可靠，局部發(fa)生(sheng)故障可通過環網(wang)供熱(re)。但投資費(fei)用高。
3. 多管(guan)制管(guan)網
一般(ban)用于(yu)以下情況：不(bu)能間斷的熱(re)(re)(re)用戶；供(gong)熱(re)(re)(re)系統中熱(re)(re)(re)用戶所(suo)需介質參數差別較大；熱(re)(re)(re)負(fu)荷變化較大：季節性熱(re)(re)(re)負(fu)荷占全年總負(fu)荷比(bi)例較大。
三、熱(re)水(shui)熱(re)力網(wang)形(xing)式的確(que)定
熱(re)(re)(re)水熱(re)(re)(re)力網宜采用閉(bi)(bi)式雙管制。以熱(re)(re)(re)電廠(chang)為熱(re)(re)(re)源的熱(re)(re)(re)水熱(re)(re)(re)力網，同(tong)時(shi)有工藝(yi)(yi)、采暖(nuan)、通(tong)風、空調(diao)、生(sheng)活熱(re)(re)(re)水多種熱(re)(re)(re)負(fu)荷(he)(he)，在生(sheng)產工藝(yi)(yi)熱(re)(re)(re)負(fu)荷(he)(he)與采暖(nuan)熱(re)(re)(re)負(fu)荷(he)(he)所(suo)需供(gong)熱(re)(re)(re)介質參數相(xiang)差較大，或季節性熱(re)(re)(re)負(fu)荷(he)(he)占總熱(re)(re)(re)負(fu)荷(he)(he)比例(li)較大，且技術經濟合理時(shi)，可采用閉(bi)(bi)式多管制。
當熱水(shui)熱力(li)網具有水(shui)處(chu)理(li)費用較低的豐富(fu)的補給水(shui)資源，且技術經濟合(he)理(li)時，可采用開式熱力(li)網。
當熱水(shui)熱力(li)網(wang)具有與生活熱水(shui)熱負荷相適應的廉價低位(wei)能(neng)熱源，且技術(shu)經(jing)濟合理時(shi)，可采(cai)用開式(shi)熱水(shui)網(wang)。
開式熱水(shui)(shui)熱力網在(zai)生活(huo)熱水(shui)(shui)熱負荷足夠大(da)且技(ji)術經濟合理時，可(ke)不設回水(shui)(shui)管(guan)。
四、蒸汽熱力網形(xing)式的確定(ding)
蒸汽熱(re)力網宜采(cai)用(yong)(yong)單管制。當各(ge)用(yong)(yong)戶間(jian)所(suo)需蒸汽參數相差較大(da)或季節性(xing)熱(re)負(fu)荷占總熱(re)負(fu)荷比例(li)較大(da)且技(ji)術經濟合(he)理時，蒸汽熱(re)力網可(ke)采(cai)用(yong)(yong)雙管或多(duo)管制。
蒸(zheng)(zheng)汽(qi)熱(re)力網(wang)的熱(re)負(fu)荷分期增長(chang)時(shi)，可采(cai)用(yong)雙管或多(duo)管制。蒸(zheng)(zheng)汽(qi)供熱(re)系統應(ying)創造條件采(cai)用(yong)間接(jie)換熱(re)系統。當被加熱(re)介(jie)質泄漏(lou)不會產生(sheng)危害時(shi)，其凝結水(shui)應(ying)全部回(hui)收并(bing)設置凝結水(shui)管道。
當凝(ning)結水回收(shou)時(shi)，用戶熱(re)力站應設閉式凝(ning)結水箱(xiang)，用水泵將凝(ning)結水送回熱(re)源。
五、多供熱源熱力網形式的確(que)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。
