Determining the total price of construction projects and effective control of investment are not only important components of construction project management, but also directly related to the economic benefits of investment institutions. Taking 4 different construction schemes of an oil depot as examples, the project cost evaluation index system is constructed. On this basis, technical and economic analysis was introduced through cloud model, classification standard was established, and entropy weight method was used to determine the weight of all grass⁃roots indicators. Finally, four construction schemes were evaluated based on cloud model generator. The results show that the order of membership of the schemes is M1＞M3＞M2≈M4. The peak point of M1 appears earliest, between 2.0 and 2.5, and the peak point of M4 appears later. The influential basic indexes are fire protection engineering, foundation engineering, heat insulation engineering and project measure cost, of which the measure cost accounts for more than 1/10 of the total project cost. Therefore, on the premise of ensuring the construction requirements, we should strengthen the control of the project cost in such aspects as fire engineering, foundation engineering, thermal insulation engineering and project measure cost, so as to achieve the purpose of the optimal design and the most economical investment in the construction of the best project.

Construction standardization and civilization are not only the minimum requirements of the construction site, but also the innovation of the construction field in the new era, which are related to the social and economic development and the process of national modernization.Based on the recruitment and bidding information of an oil depot and taking four different construction schemes as the basic data, a standardized construction management evaluation index system was firstly constructed. On this basis, the standardized construction scheme evaluation system was constructed by entropy weight method and comprehensive evaluation method. The results show that the degree of standardization and civilization of the four schemes is ranked as M3＞M4＞M1＞M2. The first⁃level index weight ranking is environment＞safety＞energy saving＞cost＞quality＞progress. Among them, the weight proportion of environment factor is the largest, about 0.193, and the weight proportion of project progress factor is the smallest, about 0.128. Therefore, during the construction of oil depot, the emphasis should be placed on construction environment and safety construction, and the road of green, standardized and sustainable development should be taken.

According to the principle of atomizing corona discharge, a cooking fume purifier was made, and the volt-ampere characteristic curve of atomization condition and non-atomization condition, purification efficiency and discharge current were studied. The results showed that the discharge current of atomizing corona discharge was higher than the non atomizing corona discharge current, either positive or negative corona discharge; it was not conducive to the purification of earthed negative corona discharge cooking fume purification weather the flow too large or too small; cooking fume purifier efficiency were decreased with the increase of wind speed under both condition; the efficiency and the discharge current of atomizing corona discharge cooking fume purifier was almost unchanged with the increase of application time, while both of them decrease under the non-atomizing corona.