Difference between revisions of "传统人工钻井"

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(修建、运作和维护)
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'''关于水泥的建议''':建筑和隔板(例如水箱、大坝、水道和水井)出现裂缝的常见原因是在混合和使用水泥时出错。首先,很重要的一点是使用的成分一定要纯:干净的水、沙子和岩石,这些成分必须充分混合。第二,混合时使用的水尽量少:混凝土或水泥成形即可,宁可干点,也不要成为液体。第三,在固化过程中混凝土或水泥需要保持一定的水分,至少维持一周。同时,在固化过程中应该用塑料、大树叶或其他材料覆盖在引水建筑物上以保持水分。  
 
'''关于水泥的建议''':建筑和隔板(例如水箱、大坝、水道和水井)出现裂缝的常见原因是在混合和使用水泥时出错。首先,很重要的一点是使用的成分一定要纯:干净的水、沙子和岩石,这些成分必须充分混合。第二,混合时使用的水尽量少:混凝土或水泥成形即可,宁可干点,也不要成为液体。第三,在固化过程中混凝土或水泥需要保持一定的水分,至少维持一周。同时,在固化过程中应该用塑料、大树叶或其他材料覆盖在引水建筑物上以保持水分。  
  
'''Specific advice''':
+
'''具体建议''':
[[Image:telescopic lining.jpg|thumb|right|200px|Hand-dug well with telescopic lining. Diagram: Watt, S.B.; Wood, W.E. (1979) Hand Dug Wells and their Construction. IT, London, UK.]]
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[[Image:telescopic lining.jpg|thumb|right|200px|有伸缩衬砌的人工井. 图示: Watt, S.B.; Wood, W.E. (1979) 人工钻井及修建. IT, 英国伦敦.]]
[[Image:HandDugWellConstruction.jpg|thumb|right|200px|Construction of hand dug well at Kulala Kebele, Dera Woreda, Amhara Region, Ethiopia. Photo: [http://www.flickr.com/photos/waterdotorg/4923124025/ Water.org]]]
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[[Image:HandDugWellConstruction.jpg|thumb|right|200px|在埃塞俄比亚阿姆哈拉州(Amhara)的 Kulala Kebele Dera Woreda 地区进行人工钻井. 图片来源: [http://www.flickr.com/photos/waterdotorg/4923124025/ Water.org]]]
The basic elements of a hand-dug well are illustrated in Figure 5.3. The three main elements are: <br>
+
人工井的基本要素,详情请见图示5.3,三个要素分别是: <br>
A. '''The Well Head''' - this is the part of the well which is visible above the ground. It generally consists of a protective apron and a superstructure which depends on the type of extraction system in use. <br>
+
A. '''井口装置''' - 这个部分在地表以上,它通常由防护板和上部结构(由使用的抽水系统决定)组成。<br>
B. '''The Well Shaft''' <br>
+
B. '''井身''' <br>
C. '''The Intake''' - this is the part of the well in contact with the aquifer. It is constructed in such a way that water flows from the aquifer into the well, from where it can be extracted using a bucket, a pump or another method.
+
C. '''取水口''' - 这个部分与含水层相接。因此水从含水层流进水井,然后使用水桶、水泵或其他方法将水抽出。
  
Hand-dug wells have a tendency to have very little water or even dry up in the dry season. This is largely to do with the fact
+
人工井在旱季时很可能干涸或水量极少,主要原因是取水口深度不够。浅层含水层比深层含水层更能反映补给情况,地下水位在不同季节可相差几米。在选用修建方式时应该考虑这个变化。有几种方法可保证水井的深度:
that the intake area is not deep enough inside the dry season water table. Shallow aquifers tend to reflect recharge more sharply than deeper aquifers, resulting in water table fluctuations of several metres between seasons – these fluctuations need to be accounted for in the construction method. Several techniques can ensure that wells are sunk deep enough:
+
* 使用伸缩系统修井,在地下水位之上修建永久衬砌,以及进入地下水位的小型伸缩衬砌。该系统的优势是即使日后加深小型伸缩衬砌也不会影响永久衬砌和厚板,例如第一次水井深度不够。另一个优势是井身在凿井沉箱(通过挖掘将井身放入地下)的过程中不会倾斜。
* Construct wells using a telescopic system, where an a permanent lining is created above the water table, together with a smaller diameter telescopic lining that enters the water table. The advantage of this system is that the smaller lining can be deepened at a later date without affecting the permanent lining and slab, e.g. in case the well was not sunk deep enough the first time. Another advantage is that the shaft has less chance to go out of vertical alignment during caissoning (where a shaft is sunk by digging).
+
* 在地下水位中,凿井沉箱时使用有效的排水方法。许多人工井在修建时没有使用排水泵,因此只能深入地下水位约1米。使用排水泵可以使得井身在地下水位中下沉得更深,但是请注意:
* Use an effective method of de-watering during caissoning within the water table. Many hand-dug wells are dug without using a de-watering pump – consequently, the limit of penetration into the water table is about only 1 metre. Providing a de-watering pump will allow the shaft to be sunk deeper into the water table, but note:
+
# 水泵的类型取决于地表到地下水位的距离,对于真空泵,最多可达6-7米,如果多于这个距离就需要使用潜水泵和发电机。水泵应该允许抽取一些固体颗粒。
# Type of pump depends on the height from ground level to water table – for a suction pump, the limit will be 6-7 metres, after which a submersible pump and generator needs to be considered. The type of pump should allow a certain amount of solid particles to be pumped.
+
# 如果在有人挖井时使用水泵,需要额外注意安全问题。引擎应该位于顺风处,烟气才不会进入井中,可以在横梁上临时绑一个100-150毫米的排气管用来通风(与通风厕所原理相似),潜水泵应配备断路器避免在短路时发生触电致死事故。施工工人应该穿上工作服并绑上绳子,并且应该定期进行应急与恢复系统演习。
# Attention needs to be given to safety considerations when using a motorized pump with someone digging in the well – engines should be located downwind so fumes do not enter the well, a 100 – 150mm vent pipe can be temporarily tied to the crossbeam to ventilate the well (in similar way to a VIP latrine), submersible pumps should be fitted with circuit breakers in case of electrical shortcuts to avoid electrocution, digger should be wearing construction harness attached to rope, and rescue & recovery action should be in place and practised regularly.
+
* 使用排水泵造成水井周围下陷时(在有流砂的情况下),另一个办法是使用抽泥筒。抽泥筒通常在冲击钻井时使用,它由底部有阀门的重型空心金属管组成。将抽泥筒放入井中时,沉淀物将进入井中,并且在移除抽泥筒时也不会出来。这个方法耗时更久,但是可以不使用排水泵并在地面上进行操作。既然没有抽出水,流砂就不会进入水井,井身也可以慢慢下降。
* Where using a de-watering pump results in subsidence around the well (in the case of flowing sands), another idea is to use a bailer instead of a pump. A bailer is normally used in percussion drilling, and consists of a heavy hollow metal tube with a valve on the bottom. When the bailer is dropped, sediment enters which does not come out when the bailer is removed. This method takes longer, but can be performed at ground level without a de-watering pump – since the water is not being pumped, flowing sand has less incentive to enter and the well shaft can sink slowly.
+
* 应该在旱季的后半段(地下水位最低时)挖井。
* Aim to dig wells during the latter half of the dry season when water table will be at their lowest.
 
  
 
Where deepening the well further is not possible due to water/sand ingress, jetting in the bottom of the well can provide a means of faster recharge into the well from deeper in the aquifer, meaning the well dries up less quickly. In this case a larger diameter screen (can be wrapped with geotextile) is jetted into the well base with the end protruding above the bottom of the well, after which it is plugged using a small bag of gravel.
 
Where deepening the well further is not possible due to water/sand ingress, jetting in the bottom of the well can provide a means of faster recharge into the well from deeper in the aquifer, meaning the well dries up less quickly. In this case a larger diameter screen (can be wrapped with geotextile) is jetted into the well base with the end protruding above the bottom of the well, after which it is plugged using a small bag of gravel.
  
Where wells still dry up in the dry season, recharge techniques could be used upstream of the well.
+
如果水井在旱季仍持续干涸,应在水井的上游进行补给。
  
The use of porous concrete in part of the section of the well shaft which is underwater can help increase flow velocity into the well. Porous concrete is made using a of 1 : 1 : 4 (cement : sand : aggregate) and can be used for curved blocks or also for a central portion of any pre-cast concrete ring. Also perforated pointed steel pipes can be driven horizontally into the aquifer using a jack – this can also increase flow velocity into the well.
+
在位于地下的井身部分中使用透水混凝土可帮助加快流入水井的水流速度。透水混凝土中水泥、沙子和碎石的比例为1:1:4,并可用作弯道砖或混凝土环的中间部分。也可以使用千斤顶将多孔尖头钢管钻入含水层,这也能提高流入水井的水流速度。
  
Simplify construction methods while getting a more robust end product in a safer fashion. Using lining & telescopic lining has the advantage that heavy lifting equipment for pre-cast rings is obsolete while procedures are inherently safer. Lining is made using one-skin moulds that hold concrete against the dug wall of the hole, while the telescopic shaft can be made from curved blocks built onto a foundation cutting ring – the blocks can be extended as and when necessary.
+
简化修建方法,得到更优质成品的同时达到更安全的效果。使用衬砌或伸缩衬砌更加安全,并无需再使用重型起重设备吊起预制混凝土。衬砌使用一体式模具制成,模具中装满混凝土并靠在井身,而伸缩井身可以由弯道砖砌成地基环刀,必要时可加长。
  
 
===Costs===
 
===Costs===

Revision as of 06:25, 15 November 2015

Traditional hand dug well.png
人们正在人工井中放置石衬砌. 墨西哥恰帕斯州. 图片来源: 玛雅村庄工程.

浅层井将水从含水层或人造含水层中抽出,例如在沙坝附近或池塘周围, 但不在河床中。它包括远离河流的井,或者包括从浅层含水层(以液压方式与河流相连)中取水的井。有时候,挖掘的洞大到可容纳人或者动物。
可使用手泵小型电动泵抽取水。也可使用水桶和绳子,但会增加污染的风险。因此,应该提倡使用家用水处理。

适宜条件

  • 砂砾层适合修建水井和井眼。其他选址可为花岗岩地区的风化岩石中,山区的山谷边缘或是河堤下有砂质沉淀物的河谷中。
  • 应该避免在滞水含水层中挖水井,因为滞水含水层是浅层的含水层,水补给能力和储存能力有限。

避免污染

水井应远离污染源。对于微生物污染,进水口(滤网)与污染源(如厕所)的距离应该足够远,以降低污染风险。这样,病原体在地面的潜在传播时间至少有25天。传播时间受到多孔性、水力传导性(渗透性)和水力梯度的影响。对于中等大小、多孔性一般的沙子,病原体25天能传播大约30米,但是在沉淀物更粗的地方能增加到100米。但是,如果滤网入口的位置足够深,污染源到进水口的距离可以大大缩短,这是因为含水层纵向比横向的属性更多样,这意味着使用手泵挖掘的井眼与厕所的距离可以很近而被污染的风险很低。然而,滤网的深度必须随着抽水率的增加而加深。


优势 劣势
- 人可进入水井,可日后再加深或轻松维护

- 可私人拥有或运作
- 需修建大口径水井的情况:

  1. 无法获取或维护小口径水井的水泵或特殊水桶
  2. 提水设备占用的空间更大(小水井没有这么大的空间),例如连续的锁链和水桶
  3. 希望改进或修复现有的大口径水井
  4. 含水层(储水)的透水性太低
  5. 人力成本和技术要求低
- 难度更大,修建费时更久

- 修建过程中和过后存在更大的安全隐患
- 很难避免污染
- 流入率与投入精力不成比例
- 小型水井会在长期的干旱期减少供应和用水量,尤其是在滞水含水层区域
- 手泵的劣势也与井眼相关,包括运作、维护、缺少所有权和零件问题
- 邻近河流的人工井会受到农业径流的污染
- 修建成本高(1000美元或更贵) – 根据修建材料和人工修建水井(根据深度和挖掘的难度约耗时1个月)
- 很难达到理想的深度,尤其是在流砂地区
- 含水层的水位会发生变化,可能可进行开采(含水层被压实导致无法再储存水)


应对环境变化的适应性

干旱

干旱的后果: 水含水层可能会干涸,地下水位下降。

潜在的原因: 由于降雨减少,含水层的补给变少;人口增加,用水需求增加;含水层的面积——例如滞水含水层使用速度更快;水井在地下水位中深度不够。

增加 WASH 系统的适应性: 避免滞水含水层;将水井挖得更深——在地下水位中凿井沉箱排水井;使用伸缩衬砌进行后续加深;在旱季的后半段挖井;通过含水层补给管理(MAR)的井眼补给含水层;喷射水井底部以便加快补给速度;通过使用透水混凝土和多孔尖头钢管水平钻入含水层增加水量。


更多关于治理干旱的信息,请查看: 易干旱地区具有适应性的WASH系统

修建、运作和维护

关于水泥的建议:建筑和隔板(例如水箱、大坝、水道和水井)出现裂缝的常见原因是在混合和使用水泥时出错。首先,很重要的一点是使用的成分一定要纯:干净的水、沙子和岩石,这些成分必须充分混合。第二,混合时使用的水尽量少:混凝土或水泥成形即可,宁可干点,也不要成为液体。第三,在固化过程中混凝土或水泥需要保持一定的水分,至少维持一周。同时,在固化过程中应该用塑料、大树叶或其他材料覆盖在引水建筑物上以保持水分。

具体建议:

有伸缩衬砌的人工井. 图示: Watt, S.B.; Wood, W.E. (1979) 人工钻井及修建. IT, 英国伦敦.
在埃塞俄比亚阿姆哈拉州(Amhara)的 Kulala Kebele 和 Dera Woreda 地区进行人工钻井. 图片来源: Water.org

人工井的基本要素,详情请见图示5.3,三个要素分别是:
A. 井口装置 - 这个部分在地表以上,它通常由防护板和上部结构(由使用的抽水系统决定)组成。
B. 井身
C. 取水口 - 这个部分与含水层相接。因此水从含水层流进水井,然后使用水桶、水泵或其他方法将水抽出。

人工井在旱季时很可能干涸或水量极少,主要原因是取水口深度不够。浅层含水层比深层含水层更能反映补给情况,地下水位在不同季节可相差几米。在选用修建方式时应该考虑这个变化。有几种方法可保证水井的深度:

  • 使用伸缩系统修井,在地下水位之上修建永久衬砌,以及进入地下水位的小型伸缩衬砌。该系统的优势是即使日后加深小型伸缩衬砌也不会影响永久衬砌和厚板,例如第一次水井深度不够。另一个优势是井身在凿井沉箱(通过挖掘将井身放入地下)的过程中不会倾斜。
  • 在地下水位中,凿井沉箱时使用有效的排水方法。许多人工井在修建时没有使用排水泵,因此只能深入地下水位约1米。使用排水泵可以使得井身在地下水位中下沉得更深,但是请注意:
  1. 水泵的类型取决于地表到地下水位的距离,对于真空泵,最多可达6-7米,如果多于这个距离就需要使用潜水泵和发电机。水泵应该允许抽取一些固体颗粒。
  2. 如果在有人挖井时使用水泵,需要额外注意安全问题。引擎应该位于顺风处,烟气才不会进入井中,可以在横梁上临时绑一个100-150毫米的排气管用来通风(与通风厕所原理相似),潜水泵应配备断路器避免在短路时发生触电致死事故。施工工人应该穿上工作服并绑上绳子,并且应该定期进行应急与恢复系统演习。
  • 使用排水泵造成水井周围下陷时(在有流砂的情况下),另一个办法是使用抽泥筒。抽泥筒通常在冲击钻井时使用,它由底部有阀门的重型空心金属管组成。将抽泥筒放入井中时,沉淀物将进入井中,并且在移除抽泥筒时也不会出来。这个方法耗时更久,但是可以不使用排水泵并在地面上进行操作。既然没有抽出水,流砂就不会进入水井,井身也可以慢慢下降。
  • 应该在旱季的后半段(地下水位最低时)挖井。

Where deepening the well further is not possible due to water/sand ingress, jetting in the bottom of the well can provide a means of faster recharge into the well from deeper in the aquifer, meaning the well dries up less quickly. In this case a larger diameter screen (can be wrapped with geotextile) is jetted into the well base with the end protruding above the bottom of the well, after which it is plugged using a small bag of gravel.

如果水井在旱季仍持续干涸,应在水井的上游进行补给。

在位于地下的井身部分中使用透水混凝土可帮助加快流入水井的水流速度。透水混凝土中水泥、沙子和碎石的比例为1:1:4,并可用作弯道砖或混凝土环的中间部分。也可以使用千斤顶将多孔尖头钢管钻入含水层,这也能提高流入水井的水流速度。

简化修建方法,得到更优质成品的同时达到更安全的效果。使用衬砌或伸缩衬砌更加安全,并无需再使用重型起重设备吊起预制混凝土。衬砌使用一体式模具制成,模具中装满混凝土并靠在井身,而伸缩井身可以由弯道砖砌成地基环刀,必要时可加长。

Costs

Hand-dug wells can provide a viable alternative to unhygienic, unprotected sources while avoiding the capital and maintenance costs associated with sophisticated drilling programmes or reticulated pumped systems. A range of lining types and water lifting technologies can be chosen to match the financial and management capacity of the participants in the water supply process.

Field experiences

The following projects are utilizing hand dug well techniques.

Akvorsr logo lite.png
Akvorsr logo lite.png
RSR Project 1365
Facilities Ibbagamuwa school Sri Lanka
RSR Project 1349
Safe water
for Wajir
RSR Project 822
Urban WASH II
in Monrovia
RSR Project 894
Senjeh Well
Restoration
RSR Project 896
Gboto Well
Restoration
Akvorsr logo lite.png
RSR Project 922
WaterAid Rural
WASH Project
RSR Project 933
Accelerating Sanitation and Water for All 1
RSR Project 1330
WASH services & capacity building Liberia


Manuals, videos and links

Acknowledgements