OCR Text |
Show Hitachi estimates that major CWM applications will be as follows; (1) Displacement of oil in utility boilers which were initially designed for coal firing (2) Displacement of oil in utility and industrial boilers (3) New construction of pulverized coal in utility and industrial boilers Especially in case (1), it is necessary to spend more money for coal storage and handling systems which were removed in many plants if the unit is restored to original coal firing. Therefore, it is considered that the commercial application of CWM to these boilers will be firstly realized because of the few modifications needed. Development Program 1 Target and Approach (1) Commercial Application Regarding CWM production plant, installation near the mine is preferable to the consuming site of a power plant, because of the handling and transportation cost. A concept of CWM producing and consuming plant flow is shown in Figure-1. Transportation cost is significantly important in the case of importing most of the coal used in Japan. For this reason, the following cases of CWM production are considered respectively. © Production at mining site o Production at domestic CWM center In the latter case, coal is transported from abroad in bulk, produced in CWM at a domestic base and distributed to each utility. This center has advantages of concentrated handling of various coal kinds by one center and stable supply to the utility boiler. In Japan, a COM center of 900,000 t/y is under construction as stage I for supplying to two units of which each capacity is 265 MW. It is also considered that some CWM production centers in Japan may be installed and distribute to many utility and industrial boilers by pipeline or tankers. (2) Development Step A commercialization program by Hitachi is shown in Figure-2. Considering the scaling-up, an approach method is drawn up in the following steps of the research program. Step I Fundamental Study of Preparation II Fundamental Study of Combustion III Prototype Production IV Combustion Demonstration in Utility Boiler V Commercial Application 2 |