編(bian)者按(an)：日前，國際電力行業知名刊(kan)物《Power》刊登題為“模(mo)塊化(hua)發電(dian)廠正在提高肯尼亞(ya)地(di)熱(re)效(xiao)率”的(de)(de)(de)文章(zhang)，向全球介紹(shao)(shao)我集團首創(chuang)的(de)(de)(de)地(di)熱(re)井口(kou)電(dian)站技術及其(qi)成就(jiu)。這是繼新華社、《人(ren)民日(ri)報》等中國央媒介紹(shao)(shao)開山在肯尼亞(ya)取得的(de)(de)(de)成就(jiu)之后，又一(yi)個國際(ji)級媒體的(de)(de)(de)推介。
《Power Magazine》在全(quan)(quan)球電(dian)力(li)(li)行(xing)業(ye)具(ju)有顯著(zhu)的(de)(de)影響力(li)(li)。作為全(quan)(quan)球最古老的(de)(de)能源行(xing)業(ye)期刊(kan)之(zhi)一，自1882年創(chuang)刊(kan)以(yi)來，已成為電(dian)力(li)(li)行(xing)業(ye)內的(de)(de)重(zhong)要(yao)信息來源和(he)行(xing)業(ye)標準。其影響力(li)(li)既源于權威性和(he)歷史性，還因為其擁有廣泛(fan)的(de)(de)受眾群(qun)體，讀者(zhe)涵蓋(gai)了全(quan)(quan)球電(dian)力(li)(li)行(xing)業(ye)專(zhuan)業(ye)人(ren)(ren)士(shi)，包(bao)括電(dian)力(li)(li)工程(cheng)師、運(yun)營經(jing)理、技(ji)(ji)術(shu)(shu)(shu)專(zhuan)家、決策者(zhe)和(he)企業(ye)高管，它通(tong)過(guo)提供深入的(de)(de)技(ji)(ji)術(shu)(shu)(shu)分析(xi)、案(an)例研(yan)究(jiu)和(he)行(xing)業(ye)新聞，幫助專(zhuan)業(ye)人(ren)(ren)士(shi)做出(chu)更(geng)好的(de)(de)決策和(he)理解行(xing)業(ye)動態。《Power Magazine》在全(quan)(quan)球電(dian)力(li)(li)行(xing)業(ye)扮演重(zhong)要(yao)的(de)(de)角色，既是(shi)信息傳播的(de)(de)重(zhong)要(yao)渠道，也是(shi)行(xing)業(ye)趨勢和(he)技(ji)(ji)術(shu)(shu)(shu)發展(zhan)的(de)(de)風向標，該刊(kan)物宣介(jie)開山(shan)地熱井口(kou)模塊電(dian)站技(ji)(ji)術(shu)(shu)(shu)標志著(zhu)我集(ji)團擁有自主知識產權的(de)(de)核心(xin)技(ji)(ji)術(shu)(shu)(shu)得到業(ye)內主流媒體的(de)(de)認(ren)同(tong)，也料將極大(da)地推(tui)動開山(shan)技(ji)(ji)術(shu)(shu)(shu)在全(quan)(quan)球的(de)(de)應用。
下面是本編輯部轉(zhuan)發(fa)的新聞鏈接和轉(zhuan)載文章的中英文對照文本，以饗讀者(zhe)。
原文鏈接：//www.powermag.com/a-modular-power-plant-is-steaming-up-kenyas-geothermal-efficiency/
A Modular Power Plant Is Steaming Up Kenya's Geothermal Efficiency
Sosian Menegai during the commissioning phase. Courtesy: Kaishan Group
Sosian Menengai Geothermal Power, Kenya’s newest geothermal power plant, is powered by modular technology that maximizes efficiency, reduces costs, and enhances scalability.
Kenya’s scenic Rift Valley region is a literal hotbed of geothermal potential. Part of the vast East African Rift Valley System (EARS), a 6,400-kilometer (km) tectonic divergence that is cleaving the African continent into two plates, Kenya’s Rift Valley forms a vertical corridor of intensive faulting and volcanic activity, hot springs, fumaroles, and sulfur-oozing fissures. But while the country began geothermal exploration for power development in the 1950s, most of its investments have been focused on the Olkaria region situated within Hell’s Gate National Park near the flamingo-flecked Lake Naivasha in Nakuru County. Five of six geothermal power stations in Olkaria are owned by KenGen (with a combined capacity of 799 MW), while Nevada-based Ormat Technologies owns a 150-MW plant. Olkaria plants in 2023 provided nearly 45% of Kenya’s total generation, a sizeable contribution to the East African powerhouse’s meager 3.3-GW installed capacity.
In 2008, the Geothermal Development Co. (GDC), a state-owned special-purpose vehicle tasked with accelerating the nation’s geothermal resource development, expanded its focus to the Menengai region just north of Olkaria, at the site of a massive shield volcano with one of the biggest calderas in the world. While GDC says the Menengai complex harbors a potential of 1,600 MW, its long-term goal is to develop 465 MW of geothermal steam equivalent.
In 2013, it took the first step to competitively award the first three initial 35-MW power projects at the complex to three independent power producers (IPPs): Orpower 22 (a former subsidiary of New York firm Symbion now owned by China’s Kaishan Group), South African-based Quantum Power East Africa (now majority owned by UK firm Globeleq), and Nairobi-headquartered Sosian Energy. In August 2023, the first of these projects—Menengai III, now formally known as the Sosian Menengai Geothermal Power—wrapped up a 16-month construction timeframe and began delivering first power to the grid.
Map showing location of geothermal area along the Kenyan Rift Valley. Courtesy: KenGen
A Technology Breakthrough
Sosian’s condensed timeframe is especially stunning given that traditional geothermal development can exceed seven years. This is owing in part to a complex process that involves drilling and testing multiple wells, selecting a centralized power plant location, ordering steam turbines, and constructing extensive steam collection and reinjection systems. The traditional approach is also ridden with risks, including significant delays and inefficiencies, such as energy losses from steam pressure drops, thermal losses over long distances, and the underutilization of wells with varying pressures.
Sosian, to some measure, had the benefit of the GDC’s public-private partnership model for developing Menengai, under which the GDC assumes upfront risks of geothermal development. The state company has also notably set out to develop the field in five phases, starting with a 105-MW “steam sales” model, where it supplies steam from drilled wells to the power plants via a 25-km steam gathering and piping system. As of 2023, GDC had drilled 53 wells with a potential of 169 MW.
However, the power plant’s success can also be attributed to a distinctive new geothermal development process introduced by China’s Kaishan Group. Dr. Tang Yan, general manager of Kaishan Group, recalled realizing the need for a dramatic shift at a 2015 geothermal conference in Melbourne, Australia, where experts discussed the pitfalls of conventional methods. “I said, ‘Why don’t you put a power plant on the wellhead and do it phase by phase?’ ” he recounted.
Overcoming Traditional Challenges
While the approach proposed to support incremental power production from the start while providing revenue to support future project expansion, Yan learned no technology to support the approach was commercially available. Kaishan, which had then already begun its transition from a giant Shanghai-headquartered air compressor maker to a diversified global company, jumped into action to leverage its 2012-developed Organic Rankine Cycle (ORC) expander and screw steam expander technologies.
The technologies—originally developed for waste heat recovery from refineries and steel mills—allowed Kaishan to optimize geothermal power generation by maximizing energy output from varying well conditions, reducing inefficiencies, and enabling the development of four types of decentralized, modular power plants that are quicker to deploy and more adaptable to different geothermal fields, Yan told POWER. “These modular power plants include the steam screw expander modular power plants, the steam ORC modular power plants, the brine ORC modular power plants, and the steam and brine dual resource modular power plants,” he explained.
Steam screw expanders are specifically designed to handle wet or saturated steam, which is common in geothermal wells, effectively extracting energy from a wider range of well conditions, including wells with high non-condensable gas (NCG) content that may not be suitable for traditional turbines. ORC systems, meanwhile, are adept at converting lower-temperature steam and brine—byproducts that would otherwise go to waste—into additional electricity, Yan said.
In addition, Kaishan’s modular plants can be used to form hybrid cycles or thermal systems to meet any production well conditions, maximize their power output, and eliminate low-head pressure (WHP) wasted wells or idling wells. Because the technologies can be adapted to specific geothermal resource conditions at different project sites, they can be tailored to provide stellar efficiency, he said. “We can improve the well thermal efficiency of, for example, medium enthalpy wells, to up to 18% and 19%,” he said. That compares to only 8% to 12% for traditional centralized power plants that only use single-flash steam, he noted.
he 35-MWe Sosian Menengai Geothermal Power plant was commissioned in August 2023. The plant uses two Kaishan geothermal steam counterpressure screw expanders, which discharge their exhausts into three Organic Rankine Cycle units. Courtesy: Kaishan Group
A Competitive Edge for New Geothermal Power
Kaishan quickly expanded the niche technology into a lucrative business. Since it put online the first of four phases of the 240-MW Sorik Marapi Geothermal Project in Indonesia in 2018, it has built the 10-MW Sokoria Geothermal, also in Indonesia, alongside projects in Turkey, the U.S., and Hungary. At Sosian, Kaishan’s first project in Kenya, the company served as the engineering, procurement, and construction (EPC) contractor.
According to Yan, Kaishan’s cost-effective price point proved a crucial selection advantage. Kaishan’s EPC contract is valued at $65 million, compared to a $108 million EPC contract recently awarded for Menengai II, one of the region’s three equally sized IPP projects. The price difference is rooted in the technology selection, Yan explained. While Sosian’s 35-MW project was designed as a centralized power plant, it is powered by two steam screw expanders and three wet steam ORC modular power plants.
However, GDC’s steam contains 3.3% NCG—which represents a “huge percentage,” he said. If Sosian used traditional steam turbines, they would need to expand steam at 6 bar absolute and then consume more then 30 tons of steam per hour to remove NCG using steam injectors and vacuum pumps. Instead, Sosian employs steam screw expanders and a bottom cycle to handle the saturated steam discharge, reducing the steam to atmospheric levels throughout the entire process while eliminating the parasitic power typically consumed by vacuum systems.
“The overall efficiency compared to a traditional steam turbine is a huge game changer for this site,” Yan said. “The project only needed a guarantee of 33.25 MW, and the target was 35 MW, but we’re actually generating 37 MW.” At the same time, the project doesn’t need to purchase the extra 10% of steam for a steam injector, putting less of a burden on the GDC, he said.
A Solution for Idled Wells
The modularity of the system also proved beneficial to speed up construction and, crucially, to overcome supply chain and project management challenges posed by the COVID pandemic, Yan said. Kaishan typically assembles the modules and conducts component testing in a factory setting over six to nine months, he said. “And then, when we ship to the site, usually it takes a very short time to put them together, and you don’t need to do any welding on the power modules,” he added. “That’s sometimes where quality control can be a challenge,” he noted.
The success of the Sosian Menegai project has so far sparked significant interest in Kenya’s geothermal industry, Yan said. A key reason is that Kenya has a lot of wells, and an estimated 25% to 30% of those wells may not be supported by a steam collection system, which is needed by centralized steam turbines. “They call them idled wells or wasted wells, and they sit there and do nothing,” even if it was costly to drill them, he said. “But our technology doesn’t have that limitation because we can use any good pressure, whether they can produce brine or steam.”
—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).
中文翻譯(yi)稿
模(mo)塊化發電廠(chang)正在(zai)提高肯(ken)尼亞地熱效率
調試階(jie)段(duan)的(de) Sosian Menegai。圖片來源(yuan)：開(kai)山集團
肯(ken)尼亞最新的地熱發電廠 Sosian Menengai 地熱發電廠(chang)采用模塊(kuai)化技術，可最大(da)限度提高效(xiao)率(lv)、降低成本并增強可擴展性。
肯尼亞風景秀麗的裂谷地(di)區是(shi)地(di)熱資源的寶庫(ku)。肯尼亞裂谷是(shi)廣闊的東非大裂谷系統(tong) (EARS) 的(de)(de)(de)(de)(de)一部分，東非(fei)大(da)裂(lie)谷系統(tong)是一個(ge)長(chang)達 6,400 公里(li)的(de)(de)(de)(de)(de)地質構造分叉，將(jiang)(jiang)非(fei)洲大(da)陸一分為(wei)二(er)。肯尼亞(ya)裂(lie)谷形成(cheng)了一個(ge)垂(chui)直(zhi)走廊，其中有(you)(you)(you)密(mi)集(ji)的(de)(de)(de)(de)(de)斷層和火山活動、溫泉、噴氣孔和硫磺滲出(chu)的(de)(de)(de)(de)(de)裂(lie)縫。盡管肯尼亞(ya)在 20 世紀 50 年代(dai)就開始進行地熱勘探以開發電(dian)力(li)，但其大(da)部分投資都集(ji)中在位于地獄之(zhi)門國(guo)家公園(yuan)內(nei)(nei)的(de)(de)(de)(de)(de)奧(ao)爾(er)卡里(li)亞(ya)地區(qu)，該公園(yuan)靠近納庫魯縣火烈(lie)鳥點(dian)綴的(de)(de)(de)(de)(de)納瓦(wa)(wa)沙湖。奧(ao)爾(er)卡里(li)亞(ya)的(de)(de)(de)(de)(de)六座地熱發電(dian)站中有(you)(you)(you)五座歸 KenGen 所有(you)(you)(you)（總(zong)容量為(wei) 799 兆瓦(wa)(wa)），而總(zong)部位于內(nei)(nei)華達州的(de)(de)(de)(de)(de) Ormat Technologies擁有(you)(you)(you)一座 150 兆瓦(wa)(wa)的(de)(de)(de)(de)(de)發電(dian)站。到 2023 年，奧(ao)爾(er)卡里(li)亞(ya) (Olkaria) 電(dian)廠(chang)將(jiang)(jiang)提供肯尼亞(ya)近 45% 的(de)(de)(de)(de)(de)總(zong)發電(dian)量，為(wei)這(zhe)個(ge)東非(fei)強(qiang)國(guo)僅有(you)(you)(you)的(de)(de)(de)(de)(de) 3.3 吉(ji)瓦(wa)(wa)的(de)(de)(de)(de)(de)裝機容量做出(chu)了巨大(da)貢獻。
2008 年，地(di)(di)熱(re)開發(fa)(fa)公司 (GDC) 將重點(dian)擴大到(dao)奧爾卡里(li)亞(ya)以北的(de)梅(mei)(mei)嫩(nen)蓋地(di)(di)區(qu)，該地(di)(di)區(qu)是(shi)一座巨大的(de)盾形(xing)火山，擁(yong)有世界上最大的(de)火山口(kou)之一。地(di)(di)熱(re)開發(fa)(fa)公司是(shi)一家(jia)國有特殊目(mu)的(de)公司，其任務是(shi)加速該國的(de)地(di)(di)熱(re)資源開發(fa)(fa)。GDC 表示，梅(mei)(mei)嫩(nen)蓋綜(zong)合體蘊藏著(zhu) 1,600 兆瓦的(de)地(di)(di)熱(re)潛(qian)力(li)，但(dan)其長期目(mu)標是(shi)開發(fa)(fa) 465 兆瓦的(de)地(di)(di)熱(re)蒸汽當量。
2013 年，該(gai)集團邁(mai)出(chu)了第一步，通過競爭方式將(jiang)該(gai)綜合體中的前(qian)三(san)(san)個 35 兆瓦發電項(xiang)目授(shou)予三(san)(san)家獨(du)立電力供(gong)應(ying)商 (IPP)：Orpower 22（前身為紐約 Symbion 公(gong)司(si)的(de)子公(gong)司(si)，現歸中國開山集團所有）、總部(bu)位于(yu)南非的(de) Quantum Power East Africa（現由英國公(gong)司(si) Globeleq 控(kong)股）和總部(bu)位于(yu)內羅畢的(de) Sosian Energy。2023 年 8 月(yue)，這些項(xiang)目(mu)中的(de)第一個項(xiang)目(mu)——Menengai III（現正式(shi)稱為 Sosian Menengai 地(di)熱發(fa)電項(xiang)目(mu)）結束了(le)為期 16 個月(yue)的(de)建設工期，并開始向電網輸送第一批電力。
地圖顯示了肯尼亞裂谷沿線(xian)地熱區的位置。圖片來源：KenGen
技(ji)術突破
鑒于(yu)傳(chuan)統地熱開發可能要耗(hao)時超過七(qi)年，Sosian 的(de)(de)縮(suo)短工期尤其令人震驚。這在一(yi)定(ding)程(cheng)度上歸因于(yu)一(yi)個(ge)復雜的(de)(de)過程(cheng)，包括(kuo)鉆探(tan)和(he)測(ce)試多個(ge)井、選擇集中發電廠位(wei)置、訂購(gou)蒸(zheng)汽渦輪機以及建造(zao)廣泛(fan)的(de)(de)蒸(zheng)汽收(shou)集和(he)再注(zhu)入系統。傳(chuan)統方法(fa)也(ye)充(chong)滿風險，包括(kuo)嚴重(zhong)的(de)(de)延(yan)誤和(he)效率低下(xia)，例如蒸(zheng)汽壓力下(xia)降造(zao)成的(de)(de)能量損(sun)失、長距離熱損(sun)失以及壓力變化(hua)的(de)(de)井的(de)(de)利用不足。
在某種程(cheng)度上，Sosian 受益(yi)于 GDC 開(kai)(kai)發(fa) Menengai 的(de)公(gong)私合作模式，根據該(gai)模式，GDC 承擔地熱開(kai)(kai)發(fa)的(de)前(qian)期(qi)風險(xian)。值得注(zhu)意的(de)是(shi)，這(zhe)家國(guo)有公(gong)司還計劃分五個階段開(kai)(kai)發(fa)該(gai)地熱田，首先采用(yong) 105 兆瓦的(de)“蒸汽銷售”模式，通過 25 公(gong)里(li)長的(de)蒸汽收集和管道系(xi)統將(jiang)鉆井中的(de)蒸汽供應給發(fa)電廠。截至(zhi) 2023 年，GDC 已(yi)鉆探了(le) 53 口井，潛(qian)力為 169 兆瓦。
然而，該發電(dian)廠的成功也(ye)歸功于中國(guo)開山(shan)(shan)集團(tuan)推(tui)出的獨特的新型(xing)地熱開發工藝(yi)。開山(shan)(shan)集團(tuan)總經理湯炎博士(shi)回憶說，他在 2015 年澳大利亞墨爾本舉行(xing)的地熱會議上意識到需要進行(xing)重大轉(zhuan)變，當(dang)時專家們討論了傳統方法的缺(que)陷(xian)。“我說，‘你為什么不在井口建一個發電(dian)廠，分(fen)階段進行(xing)呢？’”他回憶道。
克服傳統挑戰
雖(sui)然該方法從(cong)一開(kai)始(shi)(shi)就提(ti)出支(zhi)持增(zeng)量發電，同(tong)時提(ti)供收(shou)入(ru)以支(zhi)持未(wei)來的(de)(de)(de)(de)項目擴展(zhan)，但湯炎(yan)博(bo)士了解到，沒有支(zhi)持該方法的(de)(de)(de)(de)技術(shu)可(ke)供商業使(shi)用(yong)。開(kai)山當時已經(jing)開(kai)始(shi)(shi)從(cong)一家總部位于上海的(de)(de)(de)(de)大型空(kong)氣壓縮機制造商轉型為一家多元化的(de)(de)(de)(de)全(quan)球性公司，并立即采取行(xing)動(dong)，利用(yong)其 2012 年開(kai)發的(de)(de)(de)(de)有機朗肯循環 (ORC) 膨脹機(ji)和螺(luo)桿蒸汽膨脹機技術。
湯(tang)炎博士告訴《POWER》雜志，這些技術最初是為(wei)回收煉油廠和鋼(gang)廠的(de)廢熱(re)而開(kai)發(fa)的(de)，它使開(kai)山公司能(neng)夠通過最大限度地提(ti)高不(bu)同井(jing)況下的(de)能(neng)量輸出(chu)、減(jian)少(shao)低效(xiao)率，以及開(kai)發(fa)四種(zhong)類型的(de)分散式模塊(kuai)化(hua)發(fa)電廠來優(you)化(hua)地熱(re)發(fa)電，這些發(fa)電廠部署速度更快，更能(neng)適應不(bu)同的(de)地熱(re)田。 “這些模(mo)塊化(hua)發(fa)電(dian)廠(chang)包括蒸(zheng)汽螺桿膨脹機模(mo)塊化(hua)發(fa)電(dian)廠(chang)、蒸(zheng)汽 ORC 模(mo)塊化(hua)發(fa)電(dian)廠(chang)、鹽(yan)水 ORC 模(mo)塊化(hua)發(fa)電(dian)廠(chang)以及蒸(zheng)汽和鹽(yan)水雙資源模(mo)塊化(hua)發(fa)電(dian)廠(chang)，”他解釋說(shuo)。
蒸(zheng)(zheng)(zheng)汽(qi)螺桿膨脹機(ji)(ji)專門設(she)計(ji)用(yong)于(yu)處理地熱(re)井(jing)中常見(jian)的(de)濕蒸(zheng)(zheng)(zheng)汽(qi)或飽(bao)和蒸(zheng)(zheng)(zheng)汽(qi)，可有效從各種井(jing)況中提(ti)取(qu)能量，包括可能不(bu)適合傳統渦輪(lun)機(ji)(ji)的(de)不(bu)凝性(xing)氣體 (NCG)含量高的(de)井(jing)。與此同時，ORC 系統擅長將(jiang)低溫(wen)蒸(zheng)(zheng)(zheng)汽(qi)和鹽水（否則這些副產品將(jiang)被浪(lang)費）轉(zhuan)化為額外的(de)電能，湯炎博(bo)士說。
此(ci)外，開山的模塊(kuai)化電(dian)廠可用于形成混合循環或熱力系統(tong)，以滿足(zu)任何生產井條件，最大限度地(di)提(ti)高(gao)(gao)其(qi)發(fa)電(dian)量(liang)，并消除低壓(ya) (WHP) 浪費井或閑置井。他(ta)說，由于這些技術可以適應不同項(xiang)目地(di)點的特定地(di)熱資源條件，因此(ci)可以量(liang)身定制(zhi)以提(ti)供卓越的效(xiao)率(lv)。他(ta)說：“我們可以將(jiang)中(zhong)焓井的熱效(xiao)率(lv)提(ti)高(gao)(gao)到 18% 和 19%。”他(ta)指(zhi)出，相比之下，僅使(shi)用單次閃蒸蒸汽(qi)的傳統(tong)集中(zhong)式發(fa)電(dian)廠的熱效(xiao)率(lv)僅為 8% 至 12%。
35 MWe 的 Sosian Menengai 地(di)熱發(fa)電廠(chang)于 2023 年 8 月投入(ru)使用。該電廠(chang)使用兩臺開山(shan)地(di)熱蒸汽反壓(ya)螺桿膨脹機，將廢氣(qi)排放到三(san)個有機朗(lang)肯循(xun)環裝置(zhi)中。圖片來源(yuan)：開山(shan)集團(tuan)
新地(di)熱(re)發電的競爭優勢
開(kai)(kai)山迅速(su)將這項(xiang)小眾技術(shu)拓展(zhan)為一項(xiang)利潤豐厚的(de)業務。自2018 年(nian)在印(yin)度(du)(du)尼西亞投產 240 兆瓦 Sorik Marapi 地(di)熱(re)項(xiang)目(mu)(mu)四期(qi)工(gong)程中的(de)第一期(qi)以來，該公司(si)已在印(yin)度(du)(du)尼西亞建造了 10 兆瓦的(de) Sokoria 地(di)熱(re)項(xiang)目(mu)(mu)，此外還在土(tu)耳其、美國和匈牙利開(kai)(kai)展(zhan)了項(xiang)目(mu)(mu)。Sosian是開山在肯尼亞的第(di)一個(ge)地熱項目，公司擔任工程、采購和施工 (EPC) 承(cheng)包商。
湯(tang)炎博(bo)士表(biao)示，開山(shan)電廠(chang)具有成(cheng)本效益的(de)(de)價(jia)(jia)格點是其關鍵(jian)的(de)(de)選(xuan)擇(ze)優(you)勢(shi)。開山(shan)電廠(chang)的(de)(de) EPC 合(he)同(tong)價(jia)(jia)值(zhi) 6500 萬美元(yuan)(yuan)，而該地區(qu)三個(ge)(ge)同(tong)等規模的(de)(de) IPP 項(xiang)目之一 Menengai II 最(zui)近獲得的(de)(de) EPC 合(he)同(tong)價(jia)(jia)值(zhi) 1.08 億美元(yuan)(yuan)。湯(tang)炎博(bo)士解釋說，價(jia)(jia)格差異的(de)(de)根源在于技術選(xuan)擇(ze)。雖然 Sosian 的(de)(de) 35 兆瓦項(xiang)目設計為集中式(shi)發(fa)電廠(chang)，但它由兩個(ge)(ge)蒸汽(qi)螺(luo)桿膨脹機和三個(ge)(ge)濕蒸汽(qi) ORC 模塊化發(fa)電廠(chang)提(ti)供動力。
然而，GDC 的(de)蒸汽(qi)含有 3.3% 的(de) NCG，這(zhe)是一個“巨大(da)的(de)百(bai)分比”，他說。如果 Sosian 使用傳統的(de)蒸汽(qi)輪機，他們需要將蒸汽(qi)膨(peng)脹至 6 bar 絕(jue)對壓(ya)力，然后(hou)每小時(shi)消耗超(chao)過 30 噸的(de)蒸汽(qi)，使(shi)用蒸汽(qi)噴射器和真空泵去除(chu) NCG。相反，Sosian 使(shi)用蒸汽(qi)螺桿(gan)膨脹(zhang)機和底部循(xun)環來處理飽和蒸汽(qi)排(pai)放，在(zai)整個過程中將蒸汽(qi)降低到(dao)大氣(qi)水平，同時(shi)消除(chu)真空系統通常(chang)消耗的(de)寄生(sheng)功(gong)率(lv)。
“與(yu)傳統蒸汽輪機相(xiang)比(bi)，整體效率對(dui)于該(gai)站點來說是一個巨大的改變，”湯炎(yan)博士(shi)說道。“該(gai)項目只需要保證 33.25 兆瓦(wa)，目標是 35 兆瓦(wa)，但(dan)我們(men)實際上(shang)發電(dian)量(liang)為 37 兆瓦(wa)。”同(tong)時，該(gai)項目(mu)不需要額外購(gou)買10%的蒸(zheng)汽(qi)用(yong)于蒸(zheng)汽(qi)噴射器(qi)，從(cong)而減輕了GDC的負擔，他說。
閑置地熱(re)井的解決(jue)方案(an)
湯炎博士表示(shi)，該(gai)系統的(de)模(mo)塊化設計也有利于加快(kuai)施工速度，更(geng)重要的(de)是，有助于克服新冠疫情(qing)帶來的(de)供(gong)應鏈(lian)和項目管理挑(tiao)戰。他(ta)說，開(kai)山通常(chang)會在(zai)六到(dao)九個(ge)月的(de)時(shi)(shi)間內組裝模(mo)塊并在(zai)工廠環境中進行組件測試。“然后，當我(wo)們運送到(dao)現場時(shi)(shi)，通常(chang)只需很(hen)短的(de)時(shi)(shi)間即可(ke)將它們組裝在(zai)一(yi)起，并且(qie)您(nin)無需對電(dian)源模(mo)塊進行任何(he)焊接(jie)，”他(ta)補(bu)充(chong)道。“有時(shi)(shi)，質量控(kong)制可(ke)能是一(yi)個(ge)挑(tiao)戰，”他(ta)指出。
他還說，Sosian Menegai 項目的(de)成功迄(qi)今已(yi)引起人們(men)(men)(men)對肯尼亞地熱產業的(de)極大興趣。一個關鍵(jian)原(yuan)因(yin)是肯尼亞有很多井(jing)(jing)，估計(ji)其中 25% 到 30% 的(de)井(jing)(jing)可能沒(mei)有蒸(zheng)汽(qi)收集系統(tong)(tong)，而蒸(zheng)汽(qi)收集系統(tong)(tong)是集中式蒸(zheng)汽(qi)渦輪(lun)機所必需(xu)的(de)。“他們(men)(men)(men)稱這些井(jing)(jing)為(wei)閑(xian)置井(jing)(jing)或廢棄(qi)井(jing)(jing)，它們(men)(men)(men)就放在那里，什么(me)也不做(zuo)”，即使鉆探這些井(jing)(jing)的(de)成本(ben)很高，“但我(wo)們(men)(men)(men)的(de)技術沒(mei)有這種限(xian)制，因(yin)為(wei)我(wo)們(men)(men)(men)可以使用任何良(liang)好(hao)的(de)壓力，無(wu)論(lun)它們(men)(men)(men)是產生鹽水還是蒸(zheng)汽(qi)。”
— Sonal Patel 是(shi) POWER 的高級編(bian)輯（@sonalcpatel, @POWERmagazine）