Application Of The Wavelet Analysis In The Fault Diagnosis Of Rotating Machines

Liquefied natural gas (LNG) for its safe, reliable, clean and environmentally friendly,cost-effective, flexible and easy features attracted much attention, becoming an importantenergy reserves. LNG satellite stations as most LNG chain ends directly service users, whenLNG reaches to satellite stations; it transfers a normal temperature gas by its gasification.LNG gasification process can release a lot of cold energy, about the release of830-860MJ ofenergy per ton, equivalent to electricity about231kWh. Meanwhile, LNG satellite stationsare often located in the city center, near the public buildings and the mass functionalarchitectures, that their operation and maintenance require a considerable amount of coldenergy. Therefore, building air-conditioning as the carrier will effectively recycle a lot ofLNG cold energy which used in public buildings near gasification stations. This helpsefficient use of gasified LNG cold energy, and saves a lot of building air conditioning energyconsumption.In this paper, through the discuss of LNG cold energy recovery methods（direct andindirect）, a set of design scheme of LNG cold energy utilization for air conditioningtwo-stage refrigerant transfer process was proposed. By comparing different refrigerants(ethylene glycol and brine, etc.), it selected60%of ethylene glycol solution as forst-stgerefrigerant. It also optimized the core equipment such as heat exchanger.. The system made anenergy analysis. Effectively combing the process scheme with a large industrial zone LNGstation technology, the engineering design which the system parameter is4500Nm3/h ofgasification amount and1.6MPa of gasification pressure was determined. Selecting keyequipment based on the actual process solution, it obtained650kW of heat load of each heatexchanger, and heat transfer area was respectively180m2and200m2. The project wasexpected to3.45million Yuan of the total budget and5.75-year payback period, indicating ithas a good economic benefits. Design of monitoring system could be real-time control to theoperation and adjustment of energy recovery system, and ensure the system security andreliability. The engineering solution had a good operational feasibility, high cold energyutilization efficiency, excellent power saving benefits and broad promotional valve.