scholarly journals Properties of Cement Mortar Using Limestone Sludge Powder Modified with Recycled Acetic Acid

2019 ◽  
Vol 11 (3) ◽  
pp. 879
Author(s):  
Hwa-Sung Ryu ◽  
Deuck-Mo Kim ◽  
Sang-Heon Shin ◽  
Wan-Ki Kim ◽  
Seung-Min Lim ◽  
...  

One of the various methods of manufacturing low-carbon cement is substituting limestone powder as a raw material or admixture. Limestone sludge powder (LSSP) has the same composition as that of limestone powder. The surface characteristics of LSSP powder modified with recycled acetic acid (RAA) and the characteristics of cement using this modified LSSP as a substitute were investigated in this study. The surface of LSSP modified with RAA was converted into calcium acetate and had a large grain size. When conventional LSSP was used as a substitute for cement, the initial strength increased owing to improved pore filling; however, the strength after 28 days of aging was lower than that of non-substituted cement. In the case of modified LSSP being replaced with cement at up to 10% of the cement weight, however, the calcium acetate on its surface increased the amount of hydration products in the cement, thereby increasing both the initial and the long-term strength.

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Montree Thongkam ◽  
Jinnaput Saelim ◽  
Banjong Boonchom ◽  
Somkiat Seesanong ◽  
Kittichai Chaiseeda ◽  
...  

The search for sustainable resources remains a subject of global interest. Calcium acetate used in many fields was prepared using waste scallop shell as a raw material, and its physicochemical properties were investigated. The waste scallop shells were transformed to calcium acetate compounds by reactions with four acetic acid concentrations at ambient temperature until the completely dried powder is obtained. The maximum yield of 87% with short reaction time at a low temperature was observed in the reaction of 60%w/w acetic acid with scallop shells. Thermal transformation reactions of all prepared calcium acetate samples revealed temperature conditions for heating to produce other advanced materials. FTIR and XRD results confirmed the purity and solid phase of all prepared calcium acetate samples, and they were compared with those of literatures and found to be well consistent. The obtained timber-like particles have different sizes depending on the acetic acid concentration. This work reports an easy and low-cost method with no environmental effect to produce cheap calcium products to be used in the industry.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Deuck-Mo Kim ◽  
Hwa-Sung Ryu ◽  
Sang-Heon Shin ◽  
Won-Jun Park

Concrete is one of the most widely used construction materials. There are several methods available to improve its performance, with one of them being the use of high-early-strength admixtures (HESAs). Typical HESAs include calcium nitrate, calcium chloride, and calcium formate (CF). Industrial by-products, such as acetic acid and lime stone sludge (LSS), can be used together to produce calcium acetate (CA), which can subsequently be used as a cementitious HESA. In this study, calcium carbonate and LSS were mixed with cement in weight ratios of 1 : 1, 1 : 1.5, and 1 : 2, and the properties of the as-produced CA were evaluated. CA and CF were mixed with cement in different weight ratios (0, 1, 2, and 3 wt%) to obtain CA- and CF-mortars, respectively. The flow behavior, setting time, pH, and compressive strength of these mortars were evaluated, and their X-ray diffraction patterns were also analyzed. It was found that as the CF content in the CF-mortar increased, the initial strength of the mortar also increased. However, it impaired its long-term strength. On the other hand, when 1% CA was mixed with cement, satisfactory early and long-term strengths were achieved. Thus, CA, which is obtained from industrial by-products, can be an effective HESA.


2021 ◽  
Vol 15 (3) ◽  
Author(s):  
T. Lebska ◽  
L. Bal-Prylypko ◽  
T. Kovalinska ◽  
V. Sakhno ◽  
Ye. Bondarenko ◽  
...  

The article considers the technology of maturing preserves from the meat of the Black Sea gastropod mollusc Rapana thomasiana using irradiation technologies. The methods of improving the technology of processing rapana meat have been studied in order to ensure long-term storage of the finished product without using artificial preservatives. The technology is based on the preliminary preparation of the semi-finished product, which includes defrosting, sorting, cutting, washing, inspection, portioning, blanching, and cooling. It has been studied how different methods of preprocessing the raw material affect the mechanostructural properties of rapana preserves. Blanching the meat of rapana has proved practical. Acetic acid has been shown to increase the sensitivity of rapana muscle tissue to picowaves. It has been found effective to soften rapana muscle tissue by marinating with acetic acid and by using picowave irradiation in various doses (2 to 10 kGy) for 60 s. The choice of the recommended dose of 2 kGy has been substantiated. It has been established that after picowave processing, the sensory properties of the finished product do not change. The system of picowave processing of preserved meat to soften its inhomogeneous structure has been described. The shift of kinetic energy in the electronic field using thin targets to form the required radiation field of different sizes has been used. This has allowed influencing the inhomogeneous structure of the raw material. It has been proved that after picowave irradiation with the dose 2 kGy, the preserved rapana meat is microbiologically safe and can be stored for 90 days at 4±2°С. The technological scheme of making preserves from rapana meat using PWP has been provided. The studies indicate that using the irradiation technology is practical, as it ensures the maturation of low-maturing aquatic organisms, extends the shelf life of food, guarantees safety and high quality


2020 ◽  
pp. 51-74
Author(s):  
I. A. Bashmakov

The article presents the key results of scenario projections that underpinned the Strategy for long-term low carbon economic development of the Russian Federation to 2050, including analysis of potential Russia’s GHG emission mitigation commitments to 2050 and assessment of relevant costs, benefits, and implications for Russia’s GDP. Low carbon transformation of the Russian economy is presented as a potential driver for economic growth that offers trillions-of-dollars-worth market niches for low carbon products by mid-21st century. Transition to low carbon economic growth is irreversible. Lagging behind in this technological race entails a security risk and technological backwardness hazards.


2009 ◽  
pp. 107-120 ◽  
Author(s):  
I. Bashmakov

On the eve of the worldwide negotiations of a new climate agreement in December 2009 in Copenhagen it is important to clearly understand what Russia can do to mitigate energy-related greenhouse gas emissions in the medium (until 2020) and in the long term (until 2050). The paper investigates this issue using modeling tools and scenario approach. It concludes that transition to the "Low-Carbon Russia" scenarios must be accomplished in 2020—2030 or sooner, not only to mitigate emissions, but to block potential energy shortages and its costliness which can hinder economic growth.


2020 ◽  
Vol 6 (1) ◽  
pp. 49-54
Author(s):  
Khabib Barnoev ◽  

The article presents the results of a study to assess the functional reserve of the kidneys against the background of a comparative study of antiaggregant therapy dipyridamole and allthrombosepin in 50 patients with a relatively early stage of chronic kidney disease. Studies have shown that long-term administration of allthrombosepin to patients has resulted in better maintenance of kidney functional reserves. Therefore, our research has once again confirmed that diphtheridamol, which is widely used as an antiaggregant drug in chronic kidney disease, does not lag behind the domestic raw material allthrombosepin


Author(s):  
Miljana Mirković ◽  
Ljiljana Kljajević ◽  
Snežana Nenadović ◽  
Sabina Dolenec ◽  
Katarina Šter ◽  
...  

Nanoscale ◽  
2021 ◽  
Author(s):  
Srijan Acharya ◽  
Satyam Suwas ◽  
Kaushik Chatterjee

Metallic materials are widely used to prepare implants for both short-term and long-term use in the human body. The performance of these implants is greatly influenced by their surface characteristics,...


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Liqiang Cui ◽  
Qinya Fan ◽  
Jianxiong Sun ◽  
Guixiang Quan ◽  
Jinlong Yan ◽  
...  

AbstractFenton-like system formed in a natural soil environment deemed to be significant in the aging process of biochar. Aged biochars have distinct physico-chemical and surface properties compared to non-aged biochar. The aged biochar proved to be useful soil amendment due to its improved elements contents and surface properties. The biochar aging process resulted in increased surface area and pore volume, as well as carbon and oxygen-containing functional groups (such as C=O, –COOH, O–C=O etc.) on its surface, which were also associated with the adsorption behavior of 2,4,6-trichlorophenol (2,4,6-TCP). The biochar aging increased the adsorption capacity of 2,4,6-TCP, which was maximum at pH 3.0. The 2,4,6-TCP adsorption capacity of aged-bush biochar (ABB) and aged-peanut shell biochar (APB) was increased by 1.0–11.0% and 7.4–38.8%, respectively compared with bush biochar (BB) and peanut shell biochar (PB) at the same initial concentration of 2,4,6-TCP. All biochars had similar 2,4,6-TCP desorption rates ranging from 33.2 to 73.3% at different sorption temperatures and times. The desorbed components were mainly 2,4,6-TCP and other degraded components, which were low in concentration with small molecule substance. The results indicated that the aged-biochar could be effective for the long-term remediation of naturally organic polluted soils.


Sign in / Sign up

Export Citation Format

Share Document