【正文】 (i) A distinction should be made between existing landfills and new landfills。 (v) Finally, Member States should develop economic incentives to favor the recovery of methane gas, the use of technologies, and the reduction of the amount of anic matter deposited in landfills. Decision 99/296/CE published on April 26, 1999, modified Decision 93/389/CEE regarding the monitoring of CO2 and other greenhouse gases such as methane. This decision affirms that Member States should make an inventory of the sources of gas emissions and their elimination by drainage sites, as well as describe the policies and national regulations adopted to reduce such emissions, and thus facilitate their total elimination. As can be observed, these regulations are somewhat ambiguous in reference to the measures to be taken for the efficient management of biogas. Nevertheless, what is clear is the message regarding the need to reduce and minimize the negative impact that uncontrolled biogas emission has on the environment. 5 2. An urban waste landfill in Granada (Spain) . Profile of the landfill The landfill studied in this article is located 2 km northeast of Granada, a city in southern Spain with a population of 300,000 inhabitants. The landfill, with a surface area of Has, was in active operation from 1984 to 1999. During this period, the waste was deposited on a hillside running along the river Beiro with an average altitude of 870 and 500 m (see Fig. 1). The landfill is of medium density, and over the years was progressively covered with layers of soil from the same area and similar to that found in the bed of the landfill. The waste pacting process was carried out by means of pacting equipment, with a waste pacting degree of – Tm/m3. The leachate was collected in pools where it was pumped out again to be recirculated in the landfill. The extraction of the gas was carried out by a series of gas extraction wells separated by distances of 30–35 m. In 1999 with a view to mitigating the negative environmental impact, the landfill was sealed. Subsequently, plans were drawn up to construct installations to extract biogas and reuse it to create electrical energy. The project was carried out that same year by INAGRA (pany belonging to CESPA3). The average annual precipitation in this region fluctuates from 66 to 400 mm during the seasons of autumn and winter. The average annual temperature in Granada largely depends on the weather station where the measurements are obtained. The average temperature is 1C as measured at the Cartuja weather station in the city, whereas it is at the airport weather station, 10 km outside the city. The temperature in Granada is influenced by the proximity of the Sierra Nevada mountain range. The highest temperatures occur during the summer months, while the lowest ones occur in December and January. The thermal variation in the average annual temperatures is significant, and amounts to almost 20 1C. This is the same variation that exists between daytime and nighttime temperatures. The potential evapotranspiration of the area, as calculated by the Thornthwaite Method, reaches values ranging from 700 to 900 mm. There is generally a period of draught in the summer months. The landfill is located on the Alhambra formation, made up of conglomerates and sands, immersed 6 in a large clayey basin, reducing the capacity of water transmission in the subsoil. There are no aquifers or signs of surface or groundwater at the landfill site. After the landfill was sealed, urban waste from Granada, as well as that from other neighboring cities and towns, was treated at the Planta de Recuperacio180。 (iii) In the case of new landfills, the permits granted to controlled anaerobic deposits should be strictly monitored. In any case, it is always necessary to verify whether there are other ways of limiting methane emission, and at the same time incorporate highly efficient systems for its reception and energy evaluation。 (ii) At all landfills where biodegradable wastes are deposited, gas will be recovered, treated and recycled. If the gas obtained cannot be used to produce energy, it should be burnt。 (iii) San Marcos (San Sebastian) with waste deposits of 146,172 Tm/year and a nominal power of two engines at 650 kW。tico de Andaluc?180。 Energy recovery。 rezb, Ignacio Aguilar Pave180。 第一年的安裝和操作結(jié)果已經(jīng)出來(lái)了。 在垃圾填埋場(chǎng)對(duì)沼氣的產(chǎn)生分析表示，整體流速?gòu)?250到 550Nm3/h范圍變化，這說(shuō)明潛在的平均電力生產(chǎn)力是 4,500,000千瓦 h/year。垃圾填埋的經(jīng)濟(jì)可行性取決于資金流動(dòng)的經(jīng)濟(jì)分析，在 3年期間和 7年的另一個(gè)期間使用內(nèi)部退稅率 (IRR)作為有利參量。費(fèi)用劃分為基礎(chǔ)建設(shè)成本、每年運(yùn)行和維護(hù) (Oamp。 例如，研究表示 836千瓦引擎在最佳條件下是可實(shí)行的。氣體提取系統(tǒng)的撤除和重建是為了維護(hù)氣體高出產(chǎn)量。以下簡(jiǎn)要地描述設(shè)施的組成。 3. 安裝設(shè)計(jì) 為沼氣提取和再用提議的技術(shù)可以認(rèn)為是標(biāo)準(zhǔn)技術(shù)。 這將平均生產(chǎn)出 4,500,000千瓦 h/year的電能。項(xiàng)目實(shí)用性取決于引擎或渦輪的使用，一般是 (操作 8000h/year)或 8年 (操作 7500h/year)。 圖 3顯示了甲烷氣含量為 50和 45%時(shí)的最好和最壞情況的生產(chǎn)曲線 . 沼氣產(chǎn)量 (甲烷 45%) 沼氣產(chǎn)量 (甲烷 50%) 圖 3. 最佳與最壞的沼氣產(chǎn)量分析 . 讓我們感興趣的實(shí)際上是可利用的并且最可能的集中的生產(chǎn)，這里估計(jì)有 45%甲烷含量的生產(chǎn)符合要求。這樣生產(chǎn)水平將獲得一個(gè)從。 其它使用以實(shí)驗(yàn)為基礎(chǔ)的模型受到外環(huán)境的約束 [33]。 前面部分提出每噸垃圾產(chǎn)生的沼氣量已經(jīng)被假定計(jì)算出來(lái)。 . 沼氣的經(jīng)驗(yàn)預(yù)估 沼氣產(chǎn)生的估算是通過(guò)經(jīng)驗(yàn)計(jì)算，換句話說(shuō)，計(jì)算是使用實(shí)驗(yàn)和理論的數(shù)據(jù)。表 1得出了現(xiàn)場(chǎng)研究的結(jié)果。垃圾生產(chǎn)的增量可 以在圖 2中看出。 垃圾填埋是在阿 爾漢布拉宮一個(gè)大黏土狀水池底土下形成，上層結(jié)構(gòu)是由沙子制成，在下層中減少水傳輸容量。最高溫度在夏天的數(shù)個(gè)月而最低溫度是在十二月和一月。 隨后，計(jì)劃被草擬修建設(shè)施提取沼氣和重復(fù)利用它創(chuàng)造電能。在這個(gè)期間，垃圾沿山坡的河床放置的平均高度是 870和 500 m (參見(jiàn)圖 1). 垃圾填埋場(chǎng)是有一定密度的 , 當(dāng)數(shù)年以后發(fā)現(xiàn)前面地布滿來(lái)自相同的區(qū)域的數(shù)層土壤和類似垃圾填埋場(chǎng)的物質(zhì)。 很明顯，這些章程是為沼氣的高效率管理而采取模棱兩可的措施。(iv)當(dāng)這樣評(píng)估不可行時(shí)，基礎(chǔ)設(shè)施需為它的總?cè)紵〉糜行У淖饔?。通信 COM (96) 557包括以下內(nèi)容 [26]:(i)應(yīng)該將現(xiàn)有的垃圾填埋和新的垃圾填埋進(jìn)行區(qū)分對(duì)待 。它也強(qiáng)調(diào)了建立一個(gè)共同的戰(zhàn)略必要。在氣體不可能被重復(fù)利用創(chuàng)造能量的那些垃圾填埋，它將被監(jiān)測(cè)站焚燒和處理。它包含關(guān)于氣體管理的以下措施[24]:(i)采取適當(dāng)?shù)拇胧┛刂评盥駳怏w的儲(chǔ)積和散發(fā) 。這個(gè)方針的顯著方面是以下列各項(xiàng) [23]:(i)歐共體的會(huì)員國(guó)必須采取必要的措施提供主管當(dāng)局保證設(shè)施通過(guò)最好的可利用技術(shù)的應(yīng)用特別是管理方面，在這種情況下所有恰當(dāng)?shù)念A(yù)防措施采取防止污染 。(iv)Gungora(潘普洛納 )以 118,016 Tm/year廢儲(chǔ)蓄和一個(gè)引擎在 750千瓦 . 這些信息有力地證明生物能源是可再造能源的一個(gè)重大來(lái)源。(ii)Artigas(畢爾巴鄂 )以 243,361 Tm/year廢儲(chǔ)蓄和二個(gè)引擎在 450千瓦 。增加使用可重新開發(fā)能源技術(shù)的晉級(jí)似乎能解決這個(gè)問(wèn)題 [8,13,18]. 在西班牙 ,這樣的能源