scholarly journals Simple superphosphate by two-stage acid treatment of phosphate raw materials

2021 ◽  
Vol 939 (1) ◽  
pp. 012057
Author(s):  
D Sherkuziev

Abstract The distinguishing feature of the proposed flow method before the classical (chamber) method is that the entire production cycle of natural phosphate processing is carried out in two stages. At the first stage, the phosphorite is treated with a stoichiometric flow rate of concentrated sulphuric acid (at least 93%), under conditions of complete decomposition of phosphorite to form phosphoric acid and crystals of anhydrite (calcium sulfate). The reaction temperature is 122 °C. In the second stage, the resulting concentrated solution of phosphoric acid in a mixture with sulphur is involved in a reaction with an additional input of phosphorite, which is the basis for the mechanism of chemical formation of monocalciumphosphate and granulation of superphosphate mass. The processes for neutralizing phosphoric acid on monocalciumphosphate and for granulating the product by coagulation are combined in one apparatus. The drying stage of the product is excluded from the scheme.

2019 ◽  
Vol 140 ◽  
pp. 01002
Author(s):  
Nina Shabelskaya ◽  
Roman Medvedev ◽  
Yuliya Gaidukova ◽  
Marina Astachova

Currently, chemical wastes recycling into valuable secondary products poses a pressing challenge. During phosphoric acid production from apatite raw materials, large-tonnage phosphogypsum wastes are formed, resulting in ecosystem dysfunction. Besides, such wastes occupy significant production areas. Calcium sulfate is the main component of phosphogypsum. The paper addresses the possibility of phosphogypsum reduction to calcium sulfide, which has the capacity for luminescence under UV-light. Charcoal, sucrose, and citric acid were used as reducing agents. The obtained inorganic luminescent dyes were examined using X-ray phase analysis, scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). It was found that, in the presence of charcoal, the process is accompanied by an uneven distribution of calcium sulfide over the volume of the system and, as a consequence, an uneven glow of the sample. The use of citric acid and sucrose as reducing agents results in the synthesis of samples with a uniform glow. The efficiency of the calcium sulfate conversion to calcium sulfide is 51–58%. A mechanism of calcium sulfate reduction is proposed. The obtained results can serve as a basis for the development of a technology for the recycling of large-tonnage phosphoric acid production wastes into cheap and much-needed inorganic luminescent dyes.


2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Ivan Smirnov ◽  
Victor Keino ◽  
Ksenia Goryacheva ◽  
Alexander Shunk ◽  
Alexander Bondarev ◽  
...  

The article presents the results of the research hemostimulating activity of aqueous extracts of antler young Siberean stag and drone larvae homogenate. These substrates were obtained from raw materials of animal origin. Altai Krai andAltaiRepublicare subjects of theRussian Federationwhich is the place of production of the raw material. Experiments were conducted in two stages. The first stage - in vitro, which included a research of experimental substrates on the culture of mouse marrow cells. During the experiments were obtained different results. We counted the number of colonies grown in cell culture for this. The second stage of experimenters - in vivo. It included an assessment of the myeloprotector on model of cytostatic myelosuppression of mice and analysis of bone marrow and peripheral blood.


2014 ◽  
Vol 14 (2) ◽  
pp. 139
Author(s):  
Muhammad Lukman ◽  
Ahmad Zubaid Firdaus ◽  
Rahadian Galih

Muhammad Lukman, Ahmad Zubaid Firdaus, Rahadian GalihJurusan Teknik Industri, Fakultas Teknik, Universitas Muhammadiyah MalangJl. Raya Tlogomas No. 246 MalangLaman : [email protected] Indah Cemerlang adalah salah satu perusahaan yang bergerak dalam bidang industri bahan bangunan yaitu produk paving. Dalam proses produksi perusahaan sering melakukan perubahan komposisi bahan baku yang dipengaruhi oleh biaya bahan baku. Faktor perubahan komposisi bahan baku ini membuat kualitas mutu produk mengalami penurunan. Oleh karena itu perlu diadakan suatu penelitian untuk mengidentifikasi faktor-faktor kontrol yang berpengaruh terhadap respons cacat dengan metode Responsse Surface. Penelitian dengan metode Responsse Surface ini mempunyai dua tahap. Tahap pertama yaitu orde 1 (screening) dan tahap kedua yaitu orde 2 (optimization). Hasil orde 1 diketahui komposisi bahan baku yang memengaruhi respons cacat yaitu volume semen dan abu batu. Berdasarkan hasil tersebut maka pada tahap kedua yaitu orde 2 dilakukan percobaan untuk menentukan komposisi bahan baku yang optimal. Setting komposisi bahan baku terbaik yaitu air 20 liter, semen 47 kg, pasir 120 kg, abu batu 10,45 takaran, dengan nilai respons kecacatan sebesar 5,08 persen. Penurunan biaya bahan baku dengan menggunakan komposisi tersebut sebesar Rp49,33 per palet dan biaya kerugian kualitas mengalami penurunan sebesar Rp47.640 per minggu.Kata kunci : metode responsse surface, cacat, optimasiABSTRACTCV.   Indah Cemerlang  is a  company  for building material which  produces paving  stone. The company  often  changes  the raw materials composition which is affected  by  cost  of raw materials. Change of  the raw  materials composition  makes  product quality  lower. Therefore, a study should be conducted in order to identify  control factors  influencing on defect responsse by using Responsse  Surface  method. Responsse surface method used in this research consists of two stages. First stage, called orde 1, is dealing with screening and second stage, called orde 2, is dealing with optimization. The result of orde 1 shows that the raw materials composition influencing on defect responsse are cement volume and gray stone. According to the result of second stage, the experiment is conducted to determine optimal amount of raw materials composition. Optimal amount of the raw materials composition are 20 liters of water, 47 kilograms of cement, 120 kilograms of sand, and 10.45 doses of gray stone, with value of defect responsse 5.08%. Applying proposed composition can decrease cost of raw material by Rp 49,33 per pallet and cost of poor quality by 47.60 per week.Key words: responsse surface method, defect, optimization


2020 ◽  
Vol 120 ◽  
pp. 151-159
Author(s):  
G. V. Lisachuk ◽  
Ya. М. Pitak ◽  
R. V. Krivobok ◽  
E. V. Chefranov ◽  
V. V. Voloshchuk ◽  
...  

The article considers the slip casting technology of celsian-slavsonite ceramics with the ratio of raw materials to obtain crystalline phases of ВаAl2Si2O8: SrAl2Si2O8 – 25:75. The manufacture technology of product proceeded in two stages. The first stage of synthesis was performed in a muffle furnace at a rate of temperature of 15 deg / min at a maximum firing temperature of 1200 °C with a holding time of 2 hours. Then the synthesized ceramics were grinded for 10 minutes. The second stage was to obtain a slip with the addition of surfactants (DOLAPIX PC 67). The finished slip was poured into a plaster mold. Drying of the green sample was carried out in an oven at a temperature up to 110 °C for 3 hours. Firing of the dried sample was carried out in a muffle furnace at a rate of set temperature of 15 deg / min, at a maximum firing temperature of 1250 °C for 2 hours. The fired materials were subjected to machining. The obtained data indicate that, the best sample was fired at a temperature of 1250 ° C and had the following properties: dielectric constant — 9.4, water absorption — 5.9 %, open porosity — 14.4 %, apparent density — 2.42 g/cm3, flexural strength — 19 MPa.


Author(s):  
M. M. Ganbarov ◽  
M. M. Ataev ◽  
K. K. Gazvini

The kinetics of the process of using phosphorus-containing mineral compounds by their decomposition, which are actual problems, has been studied. At beginning of the it have been notified that the process takes place in two stages. These stages of the process are differed from each another mainly by rate of process realization, because a rate of the first stage is much more that a rate of the second stage. This fact is a reason of the deep research of kinetic of given process. Apart from that a detailed study of these processes connect with some problems of enter prices. All these question are analizied in the work, also the information by methodical carry out of experiments. Regime parameters correlation of components, concentrations of components, a time requite for realization of process are presented. The dependence of degree by different mass correlation of components from the time realization of process are also shown. In the work the types existence of precipitate, monitite brush it are shown. On base of received date a dissolubility of the base received product are graphically presented. In the work an influence of mass correlation of CaO?P2O5 and time of process realization on precipitation is studied. It have been determined that by 650C temperature a mass correlation of the base components must be equal to one, by that a time being used on neutralization process don’t play the practical role, because its increase and decrease don’t influence practically on process indices. The results shown that by equality of components CO?P2O5=1 correlation during four hours the precipitation degree makes up to 90,66 % and during 1 hour this index is 78,2 % for duringthe remaining three during this index is increased on 12 %. By using of these received data these is a possibility determination of the optimum technological conditions for given process. it is shown that there are opportunities to achieve processivization, to increase the use of raw materials and to obtain an environmentally friendly product with the introduction of regime parameters and component ratios in the absolute state.


2021 ◽  
Vol 6 (2) ◽  
pp. 242-252
Author(s):  
Somadi ◽  
Vica Mariani S

The research objective was to determine the application of Supply Chain Management (SCM) at PT Brataco Chemical Medan Branch. This research used a descriptive approach with SCM analysis. Based on the research results, the company's suppliers consist of suppliers of main and supporting raw materials. Purchases of raw materials are made by pre-order with a credit payment system. Incoming raw materials will be checked with order data. If the item does not match the order, it will be returned to the supplier for replacement. Meanwhile, the appropriate goods will be placed in the warehouse and then the production process is carried out. The production process is carried out in two stages, namely the first stage to produce low TDS & nearly neutral PH and the second stage to produce Aqua Demineralization. The production results are then checked for conformity with the predetermined standards. Products that pass will be distributed to consumers using a car provided by the company. Orders that do not fit or are defective, then consumers can return to the company to be replaced with new goods.


Author(s):  
Dale E. Bockman ◽  
L. Y. Frank Wu ◽  
Alexander R. Lawton ◽  
Max D. Cooper

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.


2020 ◽  
Vol 39 (6) ◽  
pp. 8139-8147
Author(s):  
Ranganathan Arun ◽  
Rangaswamy Balamurugan

In Wireless Sensor Networks (WSN) the energy of Sensor nodes is not certainly sufficient. In order to optimize the endurance of WSN, it is essential to minimize the utilization of energy. Head of group or Cluster Head (CH) is an eminent method to develop the endurance of WSN that aggregates the WSN with higher energy. CH for intra-cluster and inter-cluster communication becomes dependent. For complete, in WSN, the Energy level of CH extends its life of cluster. While evolving cluster algorithms, the complicated job is to identify the energy utilization amount of heterogeneous WSNs. Based on Chaotic Firefly Algorithm CH (CFACH) selection, the formulated work is named “Novel Distributed Entropy Energy-Efficient Clustering Algorithm”, in short, DEEEC for HWSNs. The formulated DEEEC Algorithm, which is a CH, has two main stages. In the first stage, the identification of temporary CHs along with its entropy value is found using the correlative measure of residual and original energy. Along with this, in the clustering algorithm, the rotating epoch and its entropy value must be predicted automatically by its sensor nodes. In the second stage, if any member in the cluster having larger residual energy, shall modify the temporary CHs in the direction of the deciding set. The target of the nodes with large energy has the probability to be CHs which is determined by the above two stages meant for CH selection. The MATLAB is required to simulate the DEEEC Algorithm. The simulated results of the formulated DEEEC Algorithm produce good results with respect to the energy and increased lifetime when it is correlated with the current traditional clustering protocols being used in the Heterogeneous WSNs.


Author(s):  
Fitriah Khoirunnisa ◽  
Friska Septiani Silitonga ◽  
Veri Firmansyah

Penelitian ini bertujuan menganalisis kebutuhan petunjuk praktikum berbasis Keterampilan Proses Sains (KPS) untuk mencapai kemampuan merancang eksperimen pada materi kalor reaksi kalorimetri. Penelitian dilakukan terhadap peserta didik kelas XI SMA Negeri 2 Kota Tanjungpinang. Variabel penelitian mencakup analisis kebutuhan bahan ajar dan analisis kesesuaian Kompetensi Inti (KI) dan Kompetensi Dasar (KD). Jenis penelitian yang dilakukan adalah penelitian deskriptif kualitatif. Tahapan pertama dalam penelitian ini adalah menganalisis kebutuhan bahan ajar dengan cara membandingkan dua petunjuk praktikum yang selama ini telah digunakan di sekolah tersebut, ditinjau dari aspek struktur format penulisan, aspek kreativitas, dan aspek keterampilan proses sains yang terdapat dalam petunjuk praktikum. Sehingga didapatkan kesimpulan bahwa petunjuk praktikum yang selama ini digunakan tidak memberikan kesempatan kepada peserta didiknya untuk merancang eksperimen yang telah ditentukan. Tahapan kedua yaitu menganalisis kesesuaian kompetensi inti dan kompetensi dasar, yang bertujuan untuk menentukan indikator pencapaian kompetensi (IPK) yang akan menjadi acuan dalam mengembangkan petunjuk praktikum berbasis keterampilan proses sains. Dari kedua tahapan yang telah dilakukan maka dapat disimpulkan bahwa peserta didik memerlukan petunjuk praktikum yang mampu mengonstruksi pikiran dan mengaktifkan kinerja mereka, sehingga pendekatan Keterampilan Proses Sains menjadi pilihan dalam mengembangkan petunjuk praktikum yang sesuai dengan karakteristik kurikulum 2013.   This research aims to analyze the needs of Science Process Skills based Practical Instruction to achieve the ability to design experiments on the calor of reaction. This research was done to the students of class XI SMA Negeri 2 Tanjungpinang City. Research Variable includes the analysis of the needs of the learning materials and analysis of the suitability of the Core Competence (KI) and Basic Competence (KD). The type of research conducted is descriptive qualitative research. The first stages in this research is to analyze the needs of learning materials by comparing two practical instructions that had been implementing in the school, from the aspects of the structure of writing format, creativity, and science process skills embedded in practical instructions. The conclusion of this research that current practical instructions does not give an opportunity to the participants to design determined experiments. The second stage, namely analyzing the suitability of core competence and basic competence, which aims to determine the indicators of achievement of the competencies (GPA) which will be a reference in developing process skills-based teaching instructions science. Of the two stages that has been done then it can be concluded that learners need practical instructions to construct  thinking and and their performance, so the Science Process Skills approach is an option in developing practical instruction suitable for the characteristics of the curriculum of 2013.


2014 ◽  
Vol 59 (1) ◽  
pp. 41-52 ◽  
Author(s):  
Norbert Skoczylas

Abstract The Author endeavored to consult some of the Polish experts who deal with assessing and preventing outburst hazards as to their knowledge and experience. On the basis of this knowledge, an expert system, based on fuzzy logic, was created. The system allows automatic assessment of outburst hazard. The work was completed in two stages. The first stage involved researching relevant sources and rules concerning outburst hazard, and, subsequently, determining a number of parameters measured or observed in the mining industry that are potentially connected with the outburst phenomenon and can be useful when estimating outburst hazard. Then, the Author contacted selected experts who are actively involved in preventing outburst hazard, both in the industry and science field. The experts were anonymously surveyed, which made it possible to select the parameters which are the most essential in assessing outburst hazard. The second stage involved gaining knowledge from the experts by means of a questionnaire-interview. Subjective opinions on estimating outburst hazard on the basis of the parameters selected during the first stage were then systematized using the structures typical of the expert system based on fuzzy logic.


Sign in / Sign up

Export Citation Format

Share Document