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The problem of resource disposal of massive spent fluid catalytic catalyst needs to be solved urgently. Thus an environmentally friendly, highly efficient and economical cost adsorbent used for nitrogen and phosphorus removal was prepared from spent fluid catalytic catalyst. A novel 4A zeolite adsorbent loaded with lanthanum hydroxide (La-F4A) was prepared by acid leaching pretreatment, alkali fusion roasting hydrothermal and co-precipitation method. And use La-F4A in the study of simultaneous adsorption of ammonia-nitrogen and phosphorus in water. Adsorption experiments were carried out under the condition that the primordial concentrations of PO4 and NH4+-N were respectively 1 & 10mg/L. La-F4A has an adaptive adsorption ability on NH4+-N and PO4 in the pH range of 4-9. When the temperature is 298K, the dosage is 1.0 g/L, the contact time is 240 min, and test water pH=7, the maximum adsorption capacities for NH4+-N and PO4 are 7.64 mg/g and 0.93 mg/g respectively. The behaviours accord with the pseudo-second-order adsorption kinetic model. The adsorption of PO4 conforms to the Langmuir isotherm model while NH4+-N conforms to the Freundlich isotherm model. Coexisting anions have almost no effect on the adsorption of PO4, coexisting cations have different inhibitory effects on the adsorption of NH4+-N. After four desorption cycles, the removal efficiency of La-F4A for NH4+-N and PO4 was 77% and 93% of the initial capacity. There are both chemical adsorption and physical adsorption in the process. The ammonium removal mechanism is the ion exchange between NH4+ and Na+ in the framework, and the phosphate removal mechanism is the ligand exchange between PO4 and hydroxyl to form LaPO4. La-F4A is regarded to be an excellent adsorbent for ammonium and phosphate removal.

Cracks often appear in the process of construction and use of concrete structures. It is normal for concrete to have cracks, but the size and quantity of cracks exceed certain limits. Therefore, it is necessary to analyze the structural cracks. According to different cracks, corresponding treatment methods are given. Experiments can be done if conditions permit to verify the safety of the structure after reinforcement. The paper detected and analyzed the cracks appearing on the structure components by using an example of an underground garage project. And It was proposed about corresponding reinforcement treatment scheme. This project provides reference for similar projects or scientific research, and it provides a good research direction.

With the acceleration of globalization, industrialization and informatization, the consumption of energy resources is increasing, and the building energy consumption accounts for about 30%, so the building energy conservation has become an important part of energy conservation and emission reduction. At the same time of economic development, we should reduce building energy consumption and do a good job in building energy conservation [1], and put forward the following ways: the improvement of building’s own heat preservation and insulation performance; the improvement of energy utilization system efficiency such as electricity and heating; the development and utilization of new energy; and the proper management of energy utilization equipment system. Among them, the most effective way is to improve the thermal insulation performance of the building itself. The thermal insulation of enclosure and the air tightness of doors and windows are two important parts of thermal insulation. According to the relevant data [2], the heat loss of enclosure structure accounts for 40-50% of the building energy consumption, and the heat loss of wall structure accounts for about 70%. Therefore, the improvement of the thermal insulation requirements of the wall structure plays a huge role in building energy conservation In this paper, the experimental research on the exterior wall thermal insulation board of decoration and heat preservation integration is carried out. The influence of fly ash content, asbestos fiber content, composite active activator, waterproof agent and other additives on the physical properties of fiber-reinforced fly ash / cement board is discussed. The optimal content of various factors is determined and its mechanism is analyzed. The optimum proportion of fiber reinforced fly ash / cement board was determined by orthogonal test.