好耐冇寫過野, 襯呢個假期有少少空擋就想將最近做緊既野分享下比大家, 亦都祝大家有個好既2023年.
今日想講既就係點去Plan發電機煙通既Routing, 利申唔一定100%啱, 因爲好多都係跟Project Reference同本人對EPD (Environmental Protection Department, 環保處) Guideline既演繹去計劃, EPD自己一向講法都係Case-by-case, 姐係就算有Project Reference, 都可以有機會唔Applicable係你單Project. 所以帶定頭盔先, 唔一定跟足呢篇文寫既野就100%會過到EPD. 但呢篇文所寫既野理應係跟足EPD Guidelines, 所以跟左係大大提升EPD Approval既機會.
首先, 我地要搞清楚油缸自己本身條煙通同發電機自己條煙通先, 呢2條係唔同Party睇, 個Requirement都唔同. Fuel Tank條Flue Pipe係HKFSD睇, Exhaust Outlet 1.5m範圍内唔可以有窗/Louvre. (最新DG Guideline好似係話1.5m範圍下面都唔可以有電氣野, 如果有要轉防爆. 但呢家仲係Grace Period, 所以我冇去深究) 至於Generator Flue Pipe (Chimney), 就係EPD睇, Chimney Outlet 5m範圍裏面唔可以有窗/Louvre.
EPD對發電機同煙通主要有以下既Requirement:
咁我就簡單列左堆重點出黎同大家講:
- 首先係2.1, 如果你係打算裝一部發電機, 而部發電機係會用多過25L油的話, 你要至少係安裝前28日入曬所有相關資料(Guideline裏面既 3(a)-(e), (h)-(k))比EPD去攞Approval. 25L呢個數字係咩概念? 正常300 kVA Genset都已經用緊 87L/hr, 而300 kVA Genset亦都已經好細, 所以相信所有New Build既Genset都要入比EPD.
- 其次就係3(e), 呢句就係要係所有Chimney既Outlet畫一個5m既圓圈, 呢個圓圈入面唔可以有任何窗/開到既門, 同Intake Louvre. 有人問過Exhaust Louvre計唔計, 我自己就冇試過亦都唔覺得要冒險, 但如果真係就唔到我覺得可以入比EPD睇下批唔批. 呢段後半段都好重要, 就係煙通Outlet要係Unobstructed, 姐係上面唔可以有野擋住(例如Canopy/Building Undercover).
- 最後就係3(g), 亦都係好多人有問題既位. 因爲咁我覺得有必要Cap句野出黎警世.
(g) if the chimney is located on an unoccupied podium/roof, it should be at a
minimum distance of 3m above the parapet wall of the podium or the highest
point of any structure on the podium/roof. For an occupied podium, the 3m
should be measured from the top of the occupied structure or the highest point of
any structure on the podium/roof. In case the ventilation is good and the
emission is unlikely to cause any air pollution, the exhaust outlet may be allowed
at lower level but a minimum distance of 5m above ground should be complied
with;
呢句其實就係講, 如果條煙同射到上天台的話, 而個天台唔係平常人去到的話, 咁條煙通個Outlet位就一係要高過天台既Parapet Wall 3m 或者 高過最高點. 但係如果個天台係平常人都去到的話, 咁條煙通個Outlet位要高過最高點3m. 但係如果條煙通唔係係天台而係係Building某一個位射出黎的話, 咁就要確保唔會製造到空氣污染同個Chimney Outlet至少要離地5m.
以下係我以前其中一單Project既Chimney Outlet Location:
藍色線係Roof, 而紅色線就係Building最高點, 由圖可見, Chimney Outlet係高過最高點少少. Routing方面, 本身部發電機就係地下, 我地就同積師夾個Duct位, 貫穿曬全棟樓直接上到天台, 而條煙通就係經過呢個Duct位入上天台. 呢個Arrangement入過比EPD, 亦都approved左.
但係你可能仲會有以下幾個問題 –
疑問1: EPD唔係話要高過最高點3m咩?點解你高過最高點就OK.
答: 如果係Unoccupied Roof, 高過最高點就得. 相反, 如果係Occupied Roof, 就有機會比EPD叫你高過最高點3m. 我估計係EPD驚如果Roof積聚太多煙而又有人會行上黎的話, 會對人做成健康影響, 所以先分左Occupied Roof 同 Unoccupied Roof.
疑問2: 咁係咪一定要噴上Roof?唔可以低位出?
答: 唔一定, 我呢家做緊一單就係離地5m噴, 但未入EPD, 所以唔答得實. 但係官方答案就係: EPD會Case-by-case咁睇, 你要有心裏準備EPD隨時可以叫你射翻上Roof. 至於咩係”Ventilation is good and the emission is unlikely to cause air pollution”, 我都唔係好知EPD Officer用咩標準睇. 所以如非必要, 最好都係噴翻上Roof.
疑問3: 點分Occupied/Unoccupied Roof?
答: 要問積師/業主
所以正常Plan Routing既過程就會係咁:
- 定好發電機位置, 同積師研究煙通究竟射唔射到上Roof, 可以的話夾埋個煙通Duct位, 然後跳到第3步.
- 係離地5m既條件裏面揾一個合適既位置噴 (冇Canopy/Undercover既地方).
- 定Outlet既Level. 如果係Step 2就通常離地6m, 因爲要預1m裝個煙通帽. 如果係天台就要睇個個Roof係Occupied/Unoccupied. 如果Occupied就高過最高點3m, 如果係Unoccupied就高過最高點就得.
今次就講到呢度, 如果有問題可以再係Comment問, 新一年希望大家身體健康, 事事如意. 希望我呢一年既我冇咁忙, 可以投放多少少時間係呢個Blog到~
如果覺得呢篇文有用, 記得Share比你身邊既朋友仔睇 🙂
cw
有時間share 埋cooling tower?
KK
Any consideration to pressure drop calculation for flue pipe, muffler, catalytic converter, fittings, etc.?
Any quick sizing reference for different rating (kVA) of genset for the dia. of flue pipe? (e.g. 500kVA use 200 / 250 mm dia. flue pipe, >800kVA use 350mm dia. flue pipe, etc.)
J
可唔可以搵日講吓點樣計配電櫃的短路保護電流(KA)?
BigWa
我唔係做設計,只係作為用家,定期發電機測試人員.
遇過幾個發電機機房設計,條煙通出口就咁係發電機房門口頂位置出(我估因為慳功夫?門口頂一定唔係受力牆最易開窿?).
最後就會造成:
1.發電機著機後,發電機散熱風扇不停抽番排出發電機房門口的廢氣入發電機房,你一邊試一邊吸廢氣,仲成身臭.
2.如果著機時咁岩有同事企門口,你一著機佢就慘,噴到成身黑晒.再唔係著緊時你想出一出去,都俾D廢氣噴一下先.
又遇過HANDOVER測試著機時,成個發電機房負壓,發電機房門跟本打不開.交貨人員竟然話係正常
當時我反問如果因為停電著左機,我開唔到發電機房門,點入去檢查?又或者著緊機時發生意外要立即離開,我點逃生?
有時發現D人設計真係完全唔用腦.
jsldf
Ching講到好好可唔可以講下電氣基本知識 mccb mcb acb abb 制櫃 刀制 曲架制 水氣制 果類野
Jack
C hing 請教如何計算煙通尺寸?
AC
可以, 黎緊會出個post講點size chimney, 敬請留意 🙂
jsldf
Ching講到好好 睇你blog學到好多野
可唔可以講下電氣基本知識 mccb mcb acb abb 制櫃 刀制 曲架制 水氣制 果類野
同埋ching識唔識builder裝修野
AC
可以既, builder野就唔係好熟 🙁 都係平時地盤夾野吹兩吹
DD
pipe duct 包住條煙通上頂樓, 請教做左每隔幾多層要開access panel 呢?
AC
記得呢個冇特定要求, 但我之前個單就層層高位都有AP開到.
PGEE
Just to share, I had another case which use retractable chimney, that is when the genset is not in use, the chimney is keep in indoor behind the louvre. Whenever the genset starts, the chimney will automatically extend out of the louvre for fume exhaust. Not sure if anyone has same experience also, see if this is something that may be considered by EPD.
CH
想問下咩情況之下要裝soot filter同catalytic converter?