Means of gasses transfer outside of pretreatment station: The gasses from mine output station will be transferred to two 30000m3 gasses tanks, from each of which 2 gasses pipelines (totally 4 DN1000 pipelines) are connected to form gasses supply loop line. Depending on the pressure of 30000m3 gasses tank, the gasses is then transferred the main inletting DN1400 pipe of pretreatment system.  Between oulets of gasses tank and main inlets of pretreatment system are installed flexible connection, flame arrester, closing valve set, drainer. 

The design condition of pretreatment system is to satisfy full-load operation of 150MW generating set at 30% gasses concentration.  The pretreatment system consists of 10 pretreatment units. 

The factory building of pretreatment system will occupy a land of 45m*30m (length * width), which is 100sq.m less than that specified in Bidding Documents.  For details of the layout of factory building, refer to Drawing XX.01.00: Layout of Pretreatment System.  The pretreatment factory building consists of equipment room and electric workshop.  The control system is located in electric workshop, close to generating set side.  This part consists of 4 areas: transformer, frequency converter, dam , hydraulic station and water-pumping units. 

The refrigeration machine is located on the roof of control room. Refrigerating cycle water pump and hydraulic pressure station share one equipment room. 

In order to reduce gasses discharge to atmosphere, 4 sets of flare system are applied to consume surplus gasses.  When the concentration of methane is 30%, the consumption capacity of each flare system will be 5000nm3/h.  The flare system is located at the east side of gasses pretreatment station.  When gasses generating set is working at normal load, the flare system will not work or burn the surplus gasses. When generating set is working at part load or under maintenance, the flare system will work to reduce gasses discharge to atmosphere.  Under full automatic mode, the above-mentioned operating conditions will swithover automatically based on gasses supply situation and availability of the generating set. 

All CDM monitoring devices of flare system complies with UNFCCC "Methodological Tool to determine project emissions from flaring gases containing methane.  The load adjustment range of a single flare system is 10%-100%. 

The flare systems are located the east side of gasses pretreatment station, at the center-to-center interval of 7.5m.  The determination of center-to-center distance of flares is as per Bidding Documents Chapter 4 last section "analysis of effect on surrounding equipment due to fume from flare."

The inlet pressure of flare will relate to outlet pressure at extraction station and resistance of ducting, with design value being 0.54kPa. 

Flare systems will be installed in containers, which consists of 4 equipment container and 1 electric container.  Each flare system will include one centralized control system, mounted inside electric container, to allow local control and data processing, and realize communication with upper computer inside pretreatment workshop control room. Important data can be monitored and main actions can be completed at the upper computer inside pretreatment workshop control room. 

2.1 Technical description gasses pretreatment system

Pretreatment system will be supplied by Beijing Shidaitaoyuan Environmental Technology Co., Ltd. 

The pretreatment system is designed to satisfy the full-power operation of 38 MWM gasses generating sets.  According to the Bidding Documents, it is designed based on 30% concentration, therefore, the max. gasses consumption of each generating set is 2987 Nm3/, totally 113506 Nm3/h for 38 sets.  The pretreatment system consists of 10 independent pretreatment units, each of which has the designed capacity of 11360Nm3/h, amounting to max. capacity of 113600Nm3/h for the whole system. 

In view of high gasses concentration (above 40%) in Jincheng region, 3 pretreatment units will be standby when gasses concentration is 40%, while 2 pretreatment units will be standby when gasses concentration is 35%.  Since, among dozens of the generating sets, there will always be a few under maintenance in turn, pretreatment system will not be designed with allowance in order to minimize initial investment. 

Pretreatment unit mainly consists of primary filter, condensation moisture removal equipment, booster fan, secondary filter, refrigerating unit, water pump, as well as connection pipes, valves, metering equipment, control & regulating equipment. 

Following dedusting, dehydration, cooling, pressure loading, the pretreatment system will satisfy the generating set. 

 

 

瓦斯预处理站外气体的输送方式：矿井抽放站输送的瓦斯先送至两台30000m³储气罐，从每个气罐引出2支瓦斯管路，总计4支DN1000的管路，形成一个供气环管，依靠30000m³储气罐本体压力，输送至预处理系统DN1400的进气母管上。从气罐的出气口到预处理的进气母管之间，分别安装了软连接、阻火器、隔断阀组、排水器等装置。

预处理系统的设计条件是30%的瓦斯浓度时，满足150MW瓦斯发电机组的满负荷运行。预处理系统采用10个预处理单元。

预处理系统厂房占地为45m×30m（长×宽），比招标文件节省占地100多平方米。预处理厂房的平面布置详见: XX.01.00 预处理系统平面布置图。预处理厂房分为设备间和电气车间两个部分。其中控制系统放置在电气车间，靠近发电机组侧。该部分包括：变压器、变频器、控制室、液压站及水泵设备间等四大区域。

预处理系统的制冷主机放置在控制室屋顶，制冷循环水泵与液压站共用一个设备间。

为了减少瓦斯对空排放，采用火炬消耗多余的瓦斯，火炬数量设置4套。在30%甲烷浓度时，每台火炬的处理能力为5000Nm³/h。火炬系统设在瓦斯预处理站的东侧。当瓦斯发电机组正常工作时，火炬不运行或者将多余的瓦斯气体燃烧；当发电机组低负荷运行或机组检修时，火炬运行，以减少瓦斯对空排放。在全自动模式下，上述各种运行工况可依据瓦斯气体的供应情况和机组的可用情况自动切换。

用于火炬的所有CDM监测设备满足UNFCCC“Methodological Tool to determine proje ct emissions from flaring gases containing methane”（联合国气候变化框架协议制定的决定含甲烷气体燃烧项目排放量的方法学工具）的要求。单台火炬的负荷调节范围为10％～100％。

火炬设置在瓦斯预处理站的东侧，每个火炬的中心距为7.5m。火炬中心距的确定见本投标技术文件第四章最后一节“火炬烟气对周围设备影响的分析”。

火炬入口压力是根据抽放站出口压力和管道阻力决定，设计值为0.5~4kPa。

火炬采用集装箱式安装，共四个设备集装箱和一个电气集装箱。四个火炬采用一套集中控制系统，设置在电气集装箱内，可实现就地控制，进行数据处理，并与设置在预处理车间控制室内的上位机实现通讯；重要参数可以实现监控，主要动作可以在预处理车间控制室内的上位机上操作完成。

2.1瓦斯预处理系统的技术描述

预处理系统由XXXX环境科技有限公司提供。

预处理系统设计满足38台MWM瓦斯发电机组满功率运行的要求。根据标书要求按照30%浓度进行设计，单台发动机组的最大耗气量为2987 Nm³/h，38台共计113506 Nm³/h。预处理系统采用10个独立的预处理单元，每个单元的设计处理能力为11360Nm³/h，系统最大处理能力为113600Nm³/h。

考虑到晋城地区的瓦斯浓度一般较高（40%以上），在40%的瓦斯浓度时，有3个预处理单元处于备用状态；在35%的瓦斯浓度时，有2个预处理单元处于备用状态。且数十台发电机组总有一些机组处于轮流的检修和维护状态，因此为了降低初投资，预处理系统不考虑设计裕量。

预处理单元主要由初级过滤、冷凝除湿设备、升压风机、精密过滤器、制冷机组、水泵等设备组成，同时，还包括连接的管道、阀门、测量仪表及控制调节设备。

 

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