Phosphoric Acid Factory Research Articles

Analysis Risk K3 Using JSA and HIRARC Methods Phosphoric Acid Factory on PT. Petrokimia Gresik

PT. Petrokimia Gresik is one of the industries that produce fertilisers, non-fertilizers, and other chemicals. PT. Petrokimia Gresik is divided into several departments, including the phosphoric acid factory. This research aims to identify and reduce potential hazards during the production process. This research uses (JSA) method to identify the hazard stage and (HIRARC) method to conduct risk analysis. Based on the risk hazard identification results, each job will be assessed based on severity and likelihood to establish the risk level. The research found that all extreme-risk jobs had 4 risks, high risks had 15 risks, medium risks had 2 risks, and no jobs with low-risk levels were found. The control plan carried out in this study is to control by elimination, engineering, administration, and personal protective equipment (PPE). Keywords: Occupational Health Safety, JSA, HIRARC.

The Use of PT Petro Kimia’s by-Product Gypsum as Fill Materials

Gypsum is a by-product of the Phosphoric Acid factory PT Gresik Petrochemicals; it is produced around 1,200,000 tons/year. In order to reduce the amount, an effort needed to use gypsum as fill materials. For this purpose, the problem needs to be considered is that gypsum should not contain substances that harmful to the environment and meet the fill materials requirements. In order to answer all these questions, chemical tests were carried out to determine its heavy metal content. Gypsum plasticity and its particle size distribution were determined by conducting Atterberg limit and sieve analysis tests. Compaction test and CBR test were also carried out to determine the density and its strength. Those results were then analyzed using "The Fifteen Point Method" to obtain a relationship curve between dry density (d) and soaked-CBR. This curve was important to determine the soaked-CBR that can be achieved by gypsum materials in the field with different compaction energy 90%, 95%, and 100% of maximum compaction energy. Chemical test result shows that all heavy metals content in gypsum material are far below the regulatory limit; therefore, it is safe for the environment. Besides, Gypsum is non-plastic (NP) material and it is classified as A-4 (AASHTO) or SM (USCS); it means that Gypsum is very good for fill materials and safe to the environment. In addition, the result from the Fifteen Point Method shows that the minimum soaked CBR value is 13% achieved by using 90% of maximum compaction energy with 30-40 % of water content. It means that the gypsum material can be used as selected fill material because it fulfils its requirement where IP10%.

Radiological and physico-chemical characterization of materials from phosphoric acid production plant to assess the workers radiological risks

The industry devoted to the production of phosphoric acid by using as raw material sedimentary phosphate rock (PR) is considered as a NORM activity (Naturally Occurring Radioactive Materials), due to the high levels of U-series radionuclides contained in this ore, which are 1–2 orders of magnitude higher than those in unperturbed soils. This fact allowed us to develop a deep characterization of the raw materials, wastes, main intermediate materials, and final products obtained at a typical phosphoric acid factory. The elemental composition (major, minor and trace elements), radionuclide concentrations, grain size distribution, mineralogy and micro-structural composition were analyzed. The aim of this characterization was to obtain information for operators and maintenance personnel involved in clean-up and waste management operations.The highest concentrations of some heavy metals and radionuclide activity concentrations were found in the “scales” (or internal incrustations)from the pipes that carry either phosphoric acid (PA) or the phosphogypsum waste (PG). The highest concentrations where found for 226Ra and 40K,with values up to 9 and 5 Bq g−1, respectively. In addition, high concentrations of many toxic heavy metals and trace elements, such as Cd, Cr, Ni, Sr, Y, V, Zn, Th, and U, were found in some sludge samples.The shielding effect of the containers/vessels/pipes has an essential role in the measured external dose in the intermediate products. The radiological implications of natural radionuclides with higher activity showed that if the maximum particulate matter concentration established in the Spanish regulation is verified, and taking into account the most conservative scenario, the annual limit of 1 mSv y−1 is not exceeded.

Effect of Pollution on the Quality of Olive Oils from Trees Grown Near a Phosphoric Acid Factory

Given the importance of olive oil as a food product worldwide and given the exposure of many productive olive orchards to many pollution sources, this work is a contribution to the clarification of atmospheric metal pollution effects on the quality of olive oil and its possible toxicity for human beings. This work is carried out on olive orchards (Olea europaea L., cv. Chemlali) situated in a polluted region close to a fertilizer factory and in a controlled, unpolluted area, managed with comparable cultivation techniques during two successive years (2015/2016 and 2016/2017). Pollution negatively affects the oxidative stability and nutritional value of olive oil, especially by decreasing the contents of antioxidant compounds and the fatty acid composition. Atmospheric metals are confirmed to have a negative effect on olive oil chemicals; oils show a disruption of their squalene, tocopherols, and triglyceride composition in comparison with control oils.Practical Applications: This study is carried out in two olive orchards (Olea europaea L., cv. Chemlali) located in a polluted area near a fertilizer factory and in a control unpolluted site, managed with similar cultivation techniques. The aim is to investigate the physiological and biochemical responses of polluted oils (PO), exposed to atmospheric metal contamination as compared to control oils (CO). The results of this study emanate from the accidental exposure to contamination sources, such as the direct contact of olives, with an elevated polluted environment that might be made more severe by gaseous air pollutants emitted by the factory. Then, air contamination avoidance from factories should be examined together with any possible probable methodologies to decrease plant tissue contamination.The SIAPE is the main pollution source in Sfax city. Vegetation developed around the city is continuously exposed to air pollution. Therefore, olive fruits are contaminated by the chemical pollution which affects the quality of olive oils.

Exergoeconomic optimization of a double effect desalination unit used in an industrial steam power plant

An exergoeconomic optimization of a double effect thermal vapor compression desalination system is performed. This unit is integrated in the thermal power plant of Phosphoric Acid factory owned by The Tunisian Chemical Group. The daily production of this unit is about 528 m3 of fresh water. A mathematical model based on energy, exergy and economic balances is established using EES software. Multi-objective optimization is carried out in the purpose to obtain the maximum exergy efficiency with minimum production cost. The effects of the main operating parameters on the desalination unit performances are analyzed.Obtained results show that, the maximum exergy efficiency is obtained for the evaporator II followed by the distillate and brine pumps. The condenser has the lowest exergy efficiency.The thermocompressor is the major contributor in exergy destruction. The mass flow rate and the pressure of the motive steam affect positively the GOR. The SPECO method is used to perform the economic optimization. The maximum exergoeconomic factor f is obtained for the evaporator II followed by the evaporator I, the thermocompressor, the distillate pump and the condenser. The optimum operating conditions leading to suitable overall exergy efficiency with low production cost of distillate water are determined.

Mineralogical stabilization of Ternesite in Belite Sulfo-Aluminate Clinker elaborated from limestone, shale and phosphogypsum

This paper investigates the mineralogical evolution of sulfoaluminate clinker elaborated from moroccan prime materials limestone, shale and phosphogypsum as a byproduct from phosphoric acid factories. The advantage of the production of this type of clinker is related to the low clinkerisation temperature which is known around 1250°C, and to less consumption quantity of limestone thus enabling less CO2 emissions during the decarbonation process compared to that of Portland cement. In this study we determine the stability conditions of belite sulfoaluminate clinker containing belite (C2S) ye’elimite (C4A3$) and ternesite (C5S2$). The hydration compounds of this clinker are also investigated. The monitoring of the synthesized and hydrated phases is performed by X-Ray Diffraction and Infrared spectroscopy. The results show the formation of ternesite at 800°C and the stabilization of clinker containing y’elminite, belite and ternesite at temperatures between 1100 and 1250°C.

Mineralogical stabilization of Ternesite in Belite Sulfo-Aluminate Clinker elaborated from limestone, shale and phosphogypsum

This paper investigates the mineralogical evolution of sulfoaluminate clinker elaborated from moroccan prime materials limestone, shale and phosphogypsum as a byproduct from phosphoric acid factories. The advantage of the production of this type of clinker is related to the low clinkerisation temperature which is known around 1250°C, and to less consumption quantity of limestone thus enabling less CO2 emissions during the decarbonation process compared to that of Portland cement. In this study we determine the stability conditions of belite sulfoaluminate clinker containing belite (C2S) ye’elimite (C4A3$) and ternesite (C5S2$). The hydration compounds of this clinker are also investigated. The monitoring of the synthesized and hydrated phases is performed by X-Ray Diffraction and Infrared spectroscopy. The results show the formation of ternesite at 800°C and the stabilization of clinker containing y’elminite, belite and ternesite at temperatures between 1100 and 1250°C.

EXERGETIC OPTIMIZATION OF PHOSPHORIC ACID FACTORY POWER PLANT

An Energetic and Exergetic Analysis is conducted on a Steam Turbine Power Plant of an existing Phosphoric Acid Factory. The heat recovery systems used in different parts of the plant are also considered in the analysis. Mass, thermal and exergy balances are established on the main components of the factory. A numerical code is established using EES software to perform the calculations required for the thermal and exergy plant analysis. The effects of the key operating parameters such as steam pressure and temperature, mass flow rate as well as seawater temperature, on the cycle performances are investigated. The minimum Exergy Destruction Rates are obtained for the condensers and deaerators followed by the blowers and turbines. The Steam Turbine Generator STGI presents the maximum irreversibility rates of about 4.1 MW. For the explored ranges of HP steam pressure, the energy efficiencies of steam turbine generators STGI and STGII increase of about 1.37 % and 8.8 % respectively. While the exergy efficiencies increase of about 2.46 for STGI and 6.8 % for STGII. In the same way optimum HP steam flow rate values, leading to the maximum exergy efficiencies are defined.

Energetic and exergetic analysis of a steam turbine power plant in an existing phosphoric acid factory

An energetic and exergetic analysis is conducted on a Steam Turbine Power Plant of an existing Phosphoric Acid Factory. The heat recovery systems used in the different parts of the plant are also considered in the study. Mass, energy and exergy balances are established on the main compounds of the plant. A numerical code is established using EES software to perform the calculations required for the thermal and exergy plant analysis considering real variation ranges of the main operating parameters such as pressure, temperature and mass flow rate. The effects of theses parameters on the system performances are investigated.The main sources of irreversibility are the melters, followed by the heat exchangers, the steam turbine generator and the pumps. The maximum energy efficiency is obtained for the blower followed by the heat exchangers, the deaerator and the steam turbine generator. The exergy efficiency obtained for the heat exchanger, the steam turbine generator, the deaerator and the blower are 88%, 74%, 72% and 66% respectively.The effects of High Pressure steam temperature and pressure on the steam turbine generator energy and exergy efficiencies are investigated.

Synthesis of Fluorite (CaF2) Crystal from Gypsum Waste of Phosphoric Acid Factory in Silica Gel

This paper report the synthesis and characterization of fluorite single crystal prepared from gypsum waste of phosphoric acid production in silica gel. Instead of its high calcium, gypsum was used to recycle the waste which was massively produces in the phosphoric acid production. The gypsum waste, the raw material of CaCl2 supernatant, was dissolved in concentrated HCl and then precipitated as calcium oxalate (CaC2O4) by addition of ammonium oxalate. The CaCl2 was obtained by dissolving the CaC2O4 with HCl 3M. The crystals were grown at room temperature in silica gel and characterized by AAS, FTIR and powder XRD. The optimum crystal growth condition, which is pH of gel, CaCl2 concentration and growth time, were investigated. The result shows that at optimum condition of pH 5.80, CaCl2 concentrations of 1.2 M, and growth time of 144 hours, colorless crystals with the longest size of 3 mm, were obtained (72.57%). Characterization of the synthesized crystal by AAS indicates that the obtained crystal has high purity. Meanwhile, analysis by FTIR spectra shows a Ca–F peak at 775 cm-1, and powder-XRD analysis confirms that the obtained crystal was fluorite (CaF2). © 2012 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)

Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain

In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. 226Ra and 210Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 μm of high porosity, and could be easily mobilized by leaching and/or erosion.

Transfer of Cd, Pb, Ra and U from Phosphogypsum Amended Soils to Tomato Plants

About 170 million tons of phosphogypsum (PG) are annually generated worldwide as a by-product of phosphoric acid factories. Agricultural uses of PG could become the main sink for this waste, which usually contains significant radionuclide (from the 238U-series) and toxic metals concentrations. To study PG effects on pollutant uptake by crops, a completely randomised greenhouse experiment was carried out growing Lycopersicum esculentum Mill L. on a reclaimed marsh soil amended with three PG rates (treatments), corresponding to zero (control without PG application), one, three and ten times the typical PG rates used in SW Spain (20 Mg ha−1). The concentrations of Cd, Pb, U (by inductively coupled plasma mass spectroscopy) and 226Ra and 210Po (by γ-spectrometry and α-counting, respectively) were determined in soil, vegetal tissue and draining water. Cadmium concentrations in fruit increased with PG rates, reaching 44 ± 7 μg kg−1 formula weight with ten PG rates (being 50 μg kg−1 the maximum allowed concentration by EC 1881/2006 regulation). Cd transfer factors in non-edible parts were as high as 4.8 ± 0.5 (dry weight (d.w.)), two orders of magnitude higher than values found for lead, lead, uranium and radium concentrations in fruit remained below the corresponding detection limits—0.5 and 0.25 mg kg−1 and 0.6 mBq kg−1, respectively (in a d.w. basis). 238U (up to 7 μg kg−1 d.w.) and 210Po (up to 0.74 Bq kg−1 d.w.) could be measured in some fruit samples by α-spectrometry. Overall, the concentrations of these metals and radionuclides in the draining water accounted for less than 1% of the amount applied with PG.

Behaviour and fluxes of natural radionuclides in the production process of a phosphoric acid plant

In recent years there has been an increasing awareness of the occupational and public hazards of the radiological impact of non-nuclear industries which process materials containing naturally occurring radionuclides. These include the industries devoted to the production of phosphoric acid by treating sedimentary phosphate rocks enriched in radionuclides from the uranium series. With the aim of evaluating the radiological impact of a phosphoric acid factory located in the south-western Spain, the distribution and levels of radionuclides in the materials involved in its production process have been analysed. In this way, it is possible to asses the flows of radionuclides at each step and to locate those points where a possible radionuclide accumulation could be produced. A set of samples collected along the whole production process were analysed to determine their radionuclide content by both alpha-particle and gamma spectrometry techniques. The radionuclide fractionation steps and enrichment sources have been located, allowing the establishment of their mass (activity) balances per year.

Recovery of boric and phosphoric acid residues from wastewater

Residues obtained from boric and phosphoric acid factories cause some undesired environmental problems. B2O3 in sludge and reactor waste causes serious environmental problem. Recovery of B2O3 and P2O5 are important processes in the prevention of water pollution and the utilization of waste mud. Both residues include mainly borogypsum, phosphogypsum and impurities. In order to recover B2O3, Li, P2O5, F and other water‐soluble constituents, the residues were extracted at different temperatures with water, and by lime milk. P2O5 and F remove completely from wastes by washing with milk of lime. 47% of B2O3 is removed by extracting with hot water.

The role of near-shore industrial waste releases in the dispersion of radionuclides in the NE Irish Sea

Over the past 27 years, through the use of autoradiographic methods combined with field observations and laboratory studies, I have concluded that the behaviour and distribution of the α-active actinide radionuclides in the estuarine and marine sediments of the NE Irish Sea are significantly influenced by the releases of other non-radioactive industrial wastes. Since the 1700s, the various industrial activities in the Cumbrian coastal region have included: haematite mining, diverse non-ferric metal extraction industries, coal mining and a large number of blast furnaces for the manufacture of iron. More recently (1954–92), the Albright and Wilson phosphoric acid factory at Whitehaven, Cumbria, has discharged large quantities of phosphogypsum slurries into the NE Irish Sea. Iron wastes and slag products, together with phosphogypsum and its associated by-products containing the rare earth elements, are extremely reactive towards the actinides. These wastes are now slowly being removed from the region by natural processes following the rapid decline of heavy industry in the area. These wastes have been present since BNFL first started to discharge radionuclides into the NE Irish Sea and have not, so far, been considered in any models for the dispersion of radionuclides in the region. It is shown that sediments of the NE Irish Sea and local estuaries contain a significant part of the actinide content as coatings on two iron minerals, magnetite and haematite; there is also a significant diffuse distribution associated with hydrated iron oxides attached to quartz grains. However, not all magnetite and haematite grains from a given site show α-activity. Relative to the intensity of the α-activity of the constituent minerals in sediments, the two iron minerals can be regarded as hot particles and are associated with a further set of far more intense hot particles that either may be totally derived from BNFL Sellafield or may also include a contribution from the Albright and Wilson effluents. The retention of actinides in sediments of the NE Irish Sea is believed to be influenced by debris derived from redox recycling. Redox debris can be distributed to depth in sediments through bioturbation. For surface sediments, the distribution is likely to be controlled by sediment mobility. Actinide-enriched magnetite and haematite placer deposits are common in the region, especially in sands. Fractionation and differentiation of iron minerals takes place within the sands as a consequence of energy inputs associated, for example, with tides and storms. Historic data for NE Irish Sea and estuarine sediments provide evidence for a change in facies from muds to sandy silts and a decrease in the concentration of iron over the past 30 years. This will influence the potential behaviour and distribution of actinides in the sediments irrespective of any reductions in discharges. The worst scenario would be continued loss of fine-grained material from the NE Irish Sea and the selective retention of iron minerals and related redox debris, such that the inventory of actinides present in the NE Irish Sea (∼95% of that discharged) becomes associated with surficial sediments. At present, evidence to support this hypothesis is meagre, but it should not be ignored as the iron mineral re-concentration processes are already well-developed.