編(bian)者按(an)：日(ri)前，國際電力行業知名刊物《Power》刊(kan)登(deng)題(ti)為“模塊化(hua)發電廠正在(zai)提高肯(ken)尼亞地(di)熱效率(lv)”的(de)文章，向全球介紹我集(ji)團首創的(de)地(di)熱井口電站技術(shu)及其成(cheng)就。這是(shi)繼新華社、《人民日報》等中(zhong)國央媒介紹開山在(zai)肯(ken)尼亞取得(de)的(de)成(cheng)就之(zhi)后，又一個國際(ji)級媒體的(de)推介。
《Power Magazine》在(zai)全(quan)球(qiu)電(dian)力(li)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)具有(you)顯(xian)著的(de)(de)影響力(li)。作(zuo)為(wei)全(quan)球(qiu)最古老(lao)的(de)(de)能源(yuan)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)期(qi)刊(kan)之一，自1882年創(chuang)刊(kan)以來(lai)，已(yi)成為(wei)電(dian)力(li)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)內(nei)的(de)(de)重(zhong)(zhong)(zhong)要(yao)(yao)信息來(lai)源(yuan)和(he)(he)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)標準。其影響力(li)既源(yuan)于權(quan)威性(xing)(xing)和(he)(he)歷史(shi)性(xing)(xing)，還因為(wei)其擁(yong)有(you)廣泛的(de)(de)受眾群(qun)體(ti)，讀者(zhe)(zhe)涵蓋了全(quan)球(qiu)電(dian)力(li)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)專業(ye)(ye)(ye)(ye)(ye)人(ren)(ren)士(shi)，包括電(dian)力(li)工程師、運營經理(li)、技(ji)術(shu)(shu)專家(jia)、決(jue)策者(zhe)(zhe)和(he)(he)企業(ye)(ye)(ye)(ye)(ye)高管(guan)，它通過提供深入的(de)(de)技(ji)術(shu)(shu)分析、案例研究和(he)(he)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)新聞，幫助專業(ye)(ye)(ye)(ye)(ye)人(ren)(ren)士(shi)做出更(geng)好的(de)(de)決(jue)策和(he)(he)理(li)解行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)動態。《Power Magazine》在(zai)全(quan)球(qiu)電(dian)力(li)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)扮(ban)演重(zhong)(zhong)(zhong)要(yao)(yao)的(de)(de)角色(se)，既是(shi)信息傳播的(de)(de)重(zhong)(zhong)(zhong)要(yao)(yao)渠道，也是(shi)行(xing)(xing)(xing)業(ye)(ye)(ye)(ye)(ye)趨勢和(he)(he)技(ji)術(shu)(shu)發展的(de)(de)風向標，該刊(kan)物宣介開山地熱井口模塊電(dian)站技(ji)術(shu)(shu)標志著我集團擁(yong)有(you)自主知(zhi)識產權(quan)的(de)(de)核心技(ji)術(shu)(shu)得(de)到業(ye)(ye)(ye)(ye)(ye)內(nei)主流媒體(ti)的(de)(de)認同，也料(liao)將極大地推動開山技(ji)術(shu)(shu)在(zai)全(quan)球(qiu)的(de)(de)應用。
下面是本編(bian)輯(ji)部轉(zhuan)發的新聞鏈接(jie)和轉(zhuan)載文章的中英文對照文本，以(yi)饗讀(du)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).
中文翻譯稿
模塊(kuai)化(hua)發電廠正在提(ti)高肯尼亞地熱效率
調試階段的 Sosian Menegai。圖片來源：開山集團
肯尼亞(ya)最(zui)新的地熱發電廠 Sosian Menengai 地熱發電廠采用模(mo)塊(kuai)化技術，可最大限度提高效率、降低(di)成本并增強可擴展性。
肯尼亞風景秀麗(li)的裂(lie)谷地區是地熱資源的寶庫。肯尼亞裂(lie)谷是廣闊的東非大裂谷系(xi)(xi)統(tong) (EARS) 的(de)(de)一(yi)(yi)部分(fen)(fen)，東(dong)非大(da)裂谷系(xi)(xi)統(tong)是一(yi)(yi)個長達(da) 6,400 公里(li)(li)的(de)(de)地(di)質構造(zao)分(fen)(fen)叉，將非洲大(da)陸一(yi)(yi)分(fen)(fen)為(wei)二。肯(ken)尼亞(ya)裂谷形成了一(yi)(yi)個垂(chui)直(zhi)走廊，其(qi)中(zhong)有(you)密集(ji)的(de)(de)斷層和火山活動、溫泉、噴(pen)氣孔和硫磺滲出(chu)的(de)(de)裂縫(feng)。盡管肯(ken)尼亞(ya)在 20 世紀 50 年代(dai)就開(kai)始進行地(di)熱勘探以開(kai)發(fa)電(dian)(dian)力，但其(qi)大(da)部分(fen)(fen)投資都集(ji)中(zhong)在位于地(di)獄之門國(guo)家公園內的(de)(de)奧爾(er)卡里(li)(li)亞(ya)地(di)區，該公園靠近(jin)納庫魯縣火烈鳥點(dian)綴的(de)(de)納瓦(wa)沙湖(hu)。奧爾(er)卡里(li)(li)亞(ya)的(de)(de)六座(zuo)地(di)熱發(fa)電(dian)(dian)站(zhan)中(zhong)有(you)五座(zuo)歸(gui) KenGen 所(suo)有(you)（總(zong)容量為(wei) 799 兆(zhao)瓦(wa)），而總(zong)部位于內華(hua)達(da)州的(de)(de) Ormat Technologies擁有(you)一(yi)(yi)座(zuo) 150 兆(zhao)瓦(wa)的(de)(de)發(fa)電(dian)(dian)站(zhan)。到 2023 年，奧爾(er)卡里(li)(li)亞(ya) (Olkaria) 電(dian)(dian)廠將提供(gong)肯(ken)尼亞(ya)近(jin) 45% 的(de)(de)總(zong)發(fa)電(dian)(dian)量，為(wei)這個東(dong)非強(qiang)國(guo)僅(jin)有(you)的(de)(de) 3.3 吉(ji)瓦(wa)的(de)(de)裝機容量做出(chu)了巨(ju)大(da)貢獻。
2008 年(nian)，地(di)(di)(di)熱(re)(re)開發(fa)(fa)公(gong)(gong)司 (GDC) 將重點擴大到(dao)奧爾卡(ka)里亞以北的梅嫩蓋(gai)地(di)(di)(di)區，該(gai)地(di)(di)(di)區是一座巨大的盾形火(huo)山，擁有世(shi)界上(shang)最大的火(huo)山口之一。地(di)(di)(di)熱(re)(re)開發(fa)(fa)公(gong)(gong)司是一家國有特殊目的公(gong)(gong)司，其任務是加速該(gai)國的地(di)(di)(di)熱(re)(re)資源開發(fa)(fa)。GDC 表示，梅嫩蓋(gai)綜合(he)體蘊藏著 1,600 兆瓦的地(di)(di)(di)熱(re)(re)潛力，但其長期目標是開發(fa)(fa) 465 兆瓦的地(di)(di)(di)熱(re)(re)蒸汽(qi)當(dang)量。
2013 年，該集團邁出了(le)第一步，通過競爭方(fang)式(shi)將該綜合(he)體中的前三(san)(san)個 35 兆瓦(wa)發電項目(mu)授予三(san)(san)家獨立電力供應(ying)商(shang) (IPP)：Orpower 22（前(qian)身為紐約(yue) Symbion 公司(si)的(de)(de)子公司(si)，現(xian)歸中國開山集團所(suo)有）、總部位于南非的(de)(de) Quantum Power East Africa（現(xian)由(you)英國公司(si) Globeleq 控股(gu)）和總部位于內羅畢的(de)(de) Sosian Energy。2023 年 8 月，這些(xie)項(xiang)目中的(de)(de)第一個項(xiang)目——Menengai III（現(xian)正式稱為 Sosian Menengai 地熱(re)發電項(xiang)目）結(jie)束了(le)為期 16 個月的(de)(de)建設工期，并開始(shi)向(xiang)電網輸(shu)送第一批電力(li)。
地(di)圖顯(xian)示(shi)了(le)肯(ken)尼亞裂谷沿(yan)線地(di)熱區的位置(zhi)。圖片來源：KenGen
技(ji)術突(tu)破
鑒于(yu)傳統(tong)地熱開(kai)發可能要耗時超過(guo)七(qi)年，Sosian 的(de)縮短工(gong)期尤其(qi)令人(ren)震驚(jing)。這在一(yi)定程(cheng)度上歸因于(yu)一(yi)個復雜的(de)過(guo)程(cheng)，包括鉆探(tan)和(he)測試多個井、選(xuan)擇集中發電廠位(wei)置、訂購蒸(zheng)(zheng)汽渦輪機(ji)以及建造廣泛的(de)蒸(zheng)(zheng)汽收集和(he)再注入系統(tong)。傳統(tong)方法也充(chong)滿風險，包括嚴重的(de)延誤和(he)效率(lv)低下，例如蒸(zheng)(zheng)汽壓(ya)力下降造成的(de)能量損失、長距離熱損失以及壓(ya)力變化的(de)井的(de)利用(yong)不(bu)足。
在某種程度上(shang)，Sosian 受益于 GDC 開發(fa)(fa)(fa) Menengai 的公(gong)私合作模式(shi)，根據該模式(shi)，GDC 承擔地(di)(di)熱(re)(re)開發(fa)(fa)(fa)的前(qian)期風險。值(zhi)得注(zhu)意的是，這(zhe)家國(guo)有公(gong)司還計劃(hua)分五個階段開發(fa)(fa)(fa)該地(di)(di)熱(re)(re)田，首先采用 105 兆瓦(wa)(wa)的“蒸汽(qi)(qi)(qi)銷售(shou)”模式(shi)，通過 25 公(gong)里長(chang)的蒸汽(qi)(qi)(qi)收(shou)集和(he)管(guan)道(dao)系統將(jiang)鉆井中的蒸汽(qi)(qi)(qi)供(gong)應(ying)給(gei)發(fa)(fa)(fa)電廠。截至 2023 年(nian)，GDC 已(yi)鉆探了 53 口井，潛(qian)力為(wei) 169 兆瓦(wa)(wa)。
然而(er)，該發電廠(chang)(chang)的(de)成功(gong)也歸功(gong)于中國開(kai)山集團推出的(de)獨特的(de)新(xin)型(xing)地(di)熱(re)開(kai)發工藝(yi)。開(kai)山集團總經理湯炎博士(shi)回憶說，他在(zai) 2015 年澳大(da)利亞(ya)墨爾本舉行(xing)的(de)地(di)熱(re)會議上意識到需要進行(xing)重(zhong)大(da)轉變，當(dang)時專家們討論(lun)了傳統(tong)方(fang)法(fa)的(de)缺陷。“我說，‘你為什么不(bu)在(zai)井(jing)口建一個發電廠(chang)(chang)，分階段進行(xing)呢？’”他回憶道(dao)。
克服傳統挑(tiao)戰(zhan)
雖然該方法(fa)從一開(kai)始就提(ti)出支(zhi)(zhi)持增(zeng)量發電(dian)，同時(shi)(shi)提(ti)供收(shou)入以(yi)支(zhi)(zhi)持未來的(de)(de)項目(mu)擴(kuo)展(zhan)，但湯炎博士了解(jie)到(dao)，沒有(you)支(zhi)(zhi)持該方法(fa)的(de)(de)技術可供商(shang)業使用。開(kai)山當時(shi)(shi)已經開(kai)始從一家總部位于上海的(de)(de)大型空(kong)氣(qi)壓縮(suo)機制造商(shang)轉型為一家多元化的(de)(de)全球性公(gong)司，并立即采取行(xing)動(dong)，利用其 2012 年開(kai)發的(de)(de)有(you)機朗肯循(xun)環 (ORC) 膨脹機(ji)和螺桿蒸汽膨(peng)脹機(ji)技術(shu)。
湯炎博(bo)士告訴《POWER》雜志，這(zhe)些技術最(zui)初是為回收煉油(you)廠(chang)和鋼廠(chang)的(de)(de)廢(fei)熱而開(kai)(kai)發(fa)的(de)(de)，它使開(kai)(kai)山公司能(neng)夠通過最(zui)大限度地(di)提(ti)高不(bu)同(tong)(tong)井況(kuang)下的(de)(de)能(neng)量輸出(chu)、減少(shao)低(di)效率，以(yi)及開(kai)(kai)發(fa)四種類型的(de)(de)分散式模塊化發(fa)電(dian)(dian)廠(chang)來優化地(di)熱發(fa)電(dian)(dian)，這(zhe)些發(fa)電(dian)(dian)廠(chang)部(bu)署(shu)速度更快，更能(neng)適應不(bu)同(tong)(tong)的(de)(de)地(di)熱田(tian)。 “這些模(mo)(mo)塊(kuai)化(hua)發(fa)(fa)電(dian)廠(chang)(chang)包(bao)括蒸汽(qi)螺桿膨脹機模(mo)(mo)塊(kuai)化(hua)發(fa)(fa)電(dian)廠(chang)(chang)、蒸汽(qi) ORC 模(mo)(mo)塊(kuai)化(hua)發(fa)(fa)電(dian)廠(chang)(chang)、鹽(yan)水(shui) ORC 模(mo)(mo)塊(kuai)化(hua)發(fa)(fa)電(dian)廠(chang)(chang)以及蒸汽(qi)和鹽(yan)水(shui)雙資源模(mo)(mo)塊(kuai)化(hua)發(fa)(fa)電(dian)廠(chang)(chang)，”他解(jie)釋說(shuo)。
蒸(zheng)(zheng)汽(qi)(qi)螺桿膨脹機專門設計用(yong)于處理地熱井中常見的濕蒸(zheng)(zheng)汽(qi)(qi)或飽和蒸(zheng)(zheng)汽(qi)(qi)，可(ke)有效從各種井況(kuang)中提取能量，包括(kuo)可(ke)能不(bu)適合(he)傳統(tong)渦(wo)輪(lun)機的不(bu)凝性氣體 (NCG)含量高的井。與此同時(shi)，ORC 系統(tong)擅長(chang)將(jiang)(jiang)低溫蒸(zheng)(zheng)汽(qi)(qi)和鹽水（否(fou)則這(zhe)些副產(chan)品將(jiang)(jiang)被(bei)浪(lang)費）轉化(hua)為額外的電(dian)能，湯炎(yan)博士說。
此(ci)外(wai)，開山的(de)模塊化電廠可(ke)(ke)用于形成混合循環或(huo)熱力系統，以滿足任何生(sheng)產井(jing)條(tiao)件，最(zui)大限度(du)地提(ti)高其發電量(liang)，并消除低壓 (WHP) 浪費井(jing)或(huo)閑置井(jing)。他說，由于這些(xie)技(ji)術可(ke)(ke)以適應不(bu)同(tong)項目地點的(de)特定地熱資源條(tiao)件，因(yin)此(ci)可(ke)(ke)以量(liang)身定制以提(ti)供卓越的(de)效率(lv)(lv)。他說：“我們可(ke)(ke)以將中(zhong)焓(han)井(jing)的(de)熱效率(lv)(lv)提(ti)高到(dao) 18% 和 19%。”他指出，相比之下(xia)，僅使用單次(ci)閃蒸蒸汽(qi)的(de)傳統集中(zhong)式(shi)發電廠的(de)熱效率(lv)(lv)僅為 8% 至 12%。
35 MWe 的(de) Sosian Menengai 地熱發電廠于 2023 年 8 月(yue)投入使(shi)用。該電廠使(shi)用兩臺開(kai)山地熱蒸汽反壓(ya)螺桿膨脹機，將廢氣(qi)排放(fang)到三個有機朗肯循環(huan)裝置中。圖片來源：開(kai)山集團
新地熱發電的競爭(zheng)優勢
開山迅速將這項(xiang)(xiang)小眾技術(shu)拓展為一項(xiang)(xiang)利(li)(li)潤(run)豐厚的(de)業(ye)務。自2018 年在(zai)印度尼(ni)西亞投產 240 兆(zhao)(zhao)瓦 Sorik Marapi 地熱項(xiang)(xiang)目(mu)四期工(gong)程中的(de)第一期以來，該公司已在(zai)印度尼(ni)西亞建造了 10 兆(zhao)(zhao)瓦的(de) Sokoria 地熱項(xiang)(xiang)目(mu)，此外還在(zai)土(tu)耳(er)其、美國和匈(xiong)牙利(li)(li)開展了項(xiang)(xiang)目(mu)。Sosian是開(kai)山在肯尼亞(ya)的第一個(ge)地熱(re)項目，公司(si)擔任工程、采購(gou)和施工 (EPC) 承包商。
湯(tang)炎博士表示，開山電(dian)(dian)(dian)廠(chang)具(ju)有成本效益的(de)(de)(de)價(jia)格(ge)點(dian)是其關鍵的(de)(de)(de)選擇優勢。開山電(dian)(dian)(dian)廠(chang)的(de)(de)(de) EPC 合同(tong)價(jia)值 6500 萬美元(yuan)，而該地區(qu)三(san)個同(tong)等規模的(de)(de)(de) IPP 項(xiang)目之(zhi)一 Menengai II 最近獲得的(de)(de)(de) EPC 合同(tong)價(jia)值 1.08 億(yi)美元(yuan)。湯(tang)炎博士解釋(shi)說，價(jia)格(ge)差異的(de)(de)(de)根(gen)源在于技術(shu)選擇。雖然 Sosian 的(de)(de)(de) 35 兆瓦(wa)項(xiang)目設(she)計為集中式發電(dian)(dian)(dian)廠(chang)，但它由兩個蒸汽螺(luo)桿膨(peng)脹機和三(san)個濕(shi)蒸汽 ORC 模塊化發電(dian)(dian)(dian)廠(chang)提(ti)供動(dong)力。
然而，GDC 的(de)蒸汽含有 3.3% 的(de) NCG，這是(shi)一(yi)個“巨(ju)大(da)的(de)百分比(bi)”，他說。如果(guo) Sosian 使用傳統(tong)的(de)蒸汽輪機，他們需要(yao)將蒸汽膨(peng)脹(zhang)至(zhi) 6 bar 絕對壓力，然后(hou)每小時消(xiao)(xiao)耗(hao)超(chao)過 30 噸的蒸汽，使(shi)(shi)用蒸汽噴射器和(he)真空(kong)泵(beng)去除(chu) NCG。相反，Sosian 使(shi)(shi)用蒸汽螺(luo)桿膨脹機(ji)和(he)底部循環來處理飽和(he)蒸汽排放，在整(zheng)個過程中將蒸汽降低到大(da)氣(qi)水(shui)平，同時消(xiao)(xiao)除(chu)真空(kong)系(xi)統通(tong)常消(xiao)(xiao)耗(hao)的寄(ji)生功率。
“與傳統蒸(zheng)汽(qi)輪(lun)機相比，整體效(xiao)率對(dui)于該(gai)站點來說是(shi)一個巨大(da)的改變，”湯(tang)炎(yan)博士說道。“該(gai)項目(mu)只需(xu)要(yao)保證(zheng) 33.25 兆(zhao)(zhao)瓦(wa)，目(mu)標(biao)是(shi) 35 兆(zhao)(zhao)瓦(wa)，但我們實際上發電(dian)量為 37 兆(zhao)(zhao)瓦(wa)。”同時，該項(xiang)目不需要額外購買10%的蒸汽(qi)(qi)用(yong)于蒸汽(qi)(qi)噴射器，從而減輕了GDC的負擔，他說。
閑(xian)置(zhi)地熱(re)井(jing)的解決方案
湯(tang)炎博士(shi)表示，該系統(tong)的(de)模(mo)(mo)塊(kuai)化(hua)設計也有利于加(jia)快施工速度，更重(zhong)要的(de)是，有助于克服新(xin)冠疫情帶來的(de)供應鏈和項目管理挑戰。他說，開山通常(chang)會在六到九個(ge)月的(de)時間(jian)內組(zu)裝(zhuang)模(mo)(mo)塊(kuai)并(bing)(bing)在工廠(chang)環境(jing)中進(jin)行組(zu)件測試。“然后，當我們(men)運送到現(xian)場時，通常(chang)只(zhi)需很短的(de)時間(jian)即(ji)可將它(ta)們(men)組(zu)裝(zhuang)在一起(qi)，并(bing)(bing)且您無需對電源模(mo)(mo)塊(kuai)進(jin)行任何焊接(jie)，”他補充道。“有時，質量控制可能是一個(ge)挑戰，”他指出。
他還說，Sosian Menegai 項目的(de)成功(gong)迄今已引(yin)起人們(men)對肯尼(ni)亞(ya)地熱產(chan)業的(de)極(ji)大興趣。一個關鍵原因是肯尼(ni)亞(ya)有很多井(jing)，估計其(qi)中 25% 到 30% 的(de)井(jing)可能沒有蒸(zheng)汽(qi)(qi)(qi)收集(ji)系統，而蒸(zheng)汽(qi)(qi)(qi)收集(ji)系統是集(ji)中式蒸(zheng)汽(qi)(qi)(qi)渦輪(lun)機所必需的(de)。“他們(men)稱這些井(jing)為閑置井(jing)或(huo)廢棄井(jing)，它(ta)們(men)就放在(zai)那里，什么也不做”，即使鉆探這些井(jing)的(de)成本很高，“但(dan)我們(men)的(de)技術沒有這種(zhong)限制，因為我們(men)可以(yi)使用任何良好的(de)壓力，無論它(ta)們(men)是產(chan)生鹽(yan)水還是蒸(zheng)汽(qi)(qi)(qi)。”
— Sonal Patel 是 POWER 的高級(ji)編輯（@sonalcpatel, @POWERmagazine）