Keywords

1 Introduction

The identification of the agents of a process is the first step when it comes to thinking and finding a solution, therefore, in principle, we must ask ourselves this question and thereby limit our scope of study. What are the residues of petroleum products? To this question, the answer is very broad, but we, in this chapter, must focus our answer on the following three:

  • Contaminated aqueous waste,

  • Out-of-spec fuels,

  • Contaminated sites.

Of all these cases, we have proven experience in their correct treatment, as readers can see both in the example we present and in the final bibliography, where they can find three of our articles with their references.

The next question we ask ourselves is where are they mainly produced? Here, we find a great multitude of locations:

  • Petroleum industries,

  • Industries in general where petroleum products are used.

The use of these products is massive in terms of quantity and activities, so it is not difficult to find problems associated with their various uses and management.

We continue with the identification of which properties, of the innumerable that they possess, are the most important for our study, identifying the following:

  • Total petroleum hydrocarbons (TPH) are used to describe a large family of several hundred chemical compounds originating from crude oil. Crude oil is used to manufacture petroleum products, which can pollute the environment. Because there are many different chemicals in crude oil and other petroleum products, it is not practical to measure each one separately. However, it is useful to measure the total amount of TPH at a site. Total petroleum hydrocarbons are a mixture of many different compounds. Everyone is exposed to TPH from different sources, including gas stations, oil spilled on pavement, and chemicals used in homes and industries. Some TPH compounds can damage the nervous system, causing headaches and dizziness. TPH has been found in at least 23 of the 1,467 on the National Priorities List identified by the U.S. Environmental Protection Agency (EPA).

  • Oils and fats, in this denomination, we have many keywords to identify them, the best known would be Paraffins, Petroleum, Mineral oil, Petrolatum, Carbomer, Microcrystalline wax, Ozokerit, Ceresin, and Vaseline. They are all heavy petroleum fractions that distill at temperatures above 300 ºC, consisting of complex mixtures of high molecular weight hydrocarbons. By themselves, these products are generally not very aggressive to health but may cause slight irritation after repeated and prolonged contact with the skin or mucous membranes. However, it should be noted that they sometimes contain additives of the most varied nature, which can be dangerous, so the safety data sheet of each particular product should always be consulted.

  • Moisture or water in petroleum products, such as lubricating oils, jet fuel, or other similar products, can have harmful effects. Moisture is often associated with corrosion and engine wear. Knowing the water content of petroleum products can prevent damage to costly infrastructure and ensure safer operations. The way to determine moisture is ASTM D6304 “Standard Test Method for the Determination of Water in Petroleum Products, Lubricating Oils and Additives by Karl Fischer Coulometric Titration” is a standard often cited for moisture determination in the specifications of various petroleum products. It was updated in January 2021 and now offers three procedures for accurate moisture determination.

  • Lower calorific value (LCV): This is the total amount of heat given off in the complete combustion of 1 kg of fuel without counting the part corresponding to the latent heat of the water vapor of combustion since no phase change occurs, and it is expelled as vapor. The calorific value is always measured per unit mass of fuel oxidized. The units of measurement vary according to the state of the fuel, solid, liquid, or gaseous.

  • Thermal conductivity is a material property that indicates the amount of heat transferred per unit cross-sectional area normal to a unit temperature gradient under steady-state conditions and in the absence of any fluid or particle motion. It is variable concerning pressure and temperature. For our work, it is a fundamental parameter since we propose its final use as a combustion element in a cement kiln.

  • Content of polluting chemicals or substances that could be harmful to health. The health effects of exposure to any hazardous substance will depend on the dose, duration, and type of exposure, the presence of other chemicals, as well as characteristics and habits. Process water, after contact with fluids, will not only be loaded in oil but also in hydrogen sulfide (H2 S), ammonia (NH3), phenols, benzene, cyanides, and suspended solid compounds containing metals and inorganic compounds. Process water must be treated during different well-identified stages before any discharge into the environment.

    Chemical risks due to the presence and use of chemicals involved in refinery/petrochemical processes must also be controlled during four main stages: production, control, storage, and maintenance.

Therefore, we have already introduced the properties and their particularities, including methods of testing and determination, this allows us to limit the particular study and its scope, avoiding making it costlier and lengthy in time, we do not want anything to serve as an excuse for not applying the “Circular Economy” as a new agent of solution to existing problems.

2 Best Available Technologies for Petroleum-Based Industrial Wastes

Once we have the waste generated and identified, both in quantities and in its properties, the choice of the best “Management Technologies” begins, being able and having to choose one or several of them for the correct management of the problem and its resolution. From the range that is presented, we will now list them:

  • Phase separation, or separation by distillation or absorption, reforming or rearrangement of the molecular structure and combination, the latter consisting of combining smaller molecules to obtain larger molecules.

  • Coagulation and flocculation, this duo of actions on waters with oil content, presents in well-designed systems, a very high efficiency of separation of solids, oils, greases, and hydrocarbons.

  • Centrifugation, in the centrifuge for oil we find equipment specially designed for the separation between phases of a solution, generally, these phases are found as a heterogeneous mixture, but after centrifugation, they are separated by differences in their densities.

  • Dissolved air flotation (DAF) is a water treatment or process that clarifies wastewater (or other water) by removing suspended matter such as oils or solids. Removal is accomplished by dissolving pressurized air in the water or wastewater and then releasing the air at atmospheric pressure in flotation tanks or basins. The release of air forms small bubbles that attach to the suspended matter and float it to the surface of the water where it will be removed by a skimming device.

  • Oil bioremediation, or better bioremediation, is defined as the use of living organisms, in this case bacteria, to remove, contain, or mitigate hazardous environmental pollutants such as oil spills in marine and other ecosystems. Bioremediation has proven to be effective in different marine-coastal ecosystems, but also in contaminated soils remediated by landfarming technologies.

  • Cracking, or breaking large molecule chains into smaller molecules, is a well-known technology in petroleum refining that could be applied, but we propose complete combustion for this particular case.

The Bref documents issued for “Refineries,” “Water treatment,” “Waste treatment,” and “Oil and Gas” set out the conclusions on best available techniques (BAT) for common treatment and management systems, all according to the latest legislation. They are therefore important and should be used as an up-to-date guide for the work described in this chapter.

The following list will serve as a guide for the reader to know which ones are applicable and to be able to locate their content quickly and effectively:

  1. 1.

    Conclusions on Best Available Techniques (BAT) under Directive 2010/75/EU of the European Parliament and the Council on industrial emissions from oil and gas refining.

  2. 2.

    Conclusions on Best Available Techniques (BAT) according to Directive 2010/75/EU of the European Parliament and of the Council in the high-volume organic chemical industry.

  3. 3.

    Integrated Pollution Prevention and Control (IPPC) Reference Document on Best Available Techniques for Mineral Oil and Gas Refineries, February 2003.

  4. 4.

    Conclusions on Best Available Techniques (BAT) for common systems for the treatment and management of wastewater and waste gases in the chemical sector under Directive 2010/75/EU of the European Parliament and of the Council.

  5. 5.

    Conclusions on Best Available Techniques (BAT) for waste treatment under Directive 2010/75/EU of the European Parliament and the Council.

  6. 6.

    Integrated Pollution Prevention and Control (IPPC) Reference Document on Best Available Techniques for the Waste Treatments Industries, August 2006.

The technologies are widely known by the industry since they are used because they are effective and their success rates and, above all, their costs are well known. For each case, the success is to determine the most appropriate one and if with only one we can solve the situation or we must combine some of them. As the reader will see in the figures in Sect. 4, we present our choices and the existing proposals.

As for the treatments available in Spain and in most developed countries, we can indicate that we know and use all of them with remarkable success, we could even export them to other areas of the planet, where they are not well known or even not available. This could also be a process of technology transfer that would imply an increase in the management of the “Circular Economy” very positive and interesting for our companies, technology centers, and above all for the good of the planet.

3 Principles to Optimize Oil Wastes

The “Circular Economy” in its principles, has the maximum reuse of waste as raw material for new products, or its use in an alternative way, in other processes avoiding the use of original raw materials not yet exploited. Therefore, we propose the treatment of these oil wastes to restore the affected environment and use them as alternative fuels in the manufacture of cement, avoiding the use of new fuels, as well as the exploitation of raw materials in a percentage, as high as possible, making it possible to leave natural resources available for other processes and future generations.

If we accept the following definition: “The circular economy is a production and consumption model that involves sharing, renting, reusing, repairing, renewing and recycling existing materials and products as many times as possible to create added value. In this way, the life cycle of products is extended.” We are quick to point out that this chapter and its example imply “renewing,” and “recycling” existing products, to which we will give a new added value, extending their life cycle and solving a serious existing pollution problem.

The future of these approaches, elimination of waste and its valorization as products in existing processes, both theoretically and in practical applications, is unquestionable, our contribution to the Circular Economy implies that “we need to be part of the solution and not part of the problem.”

Emission of petroleum-derived components into the surrounding area may affect both human health and the environment. Should these emissions take the form of a spill, this would mean they would turn into a source of soil and underground water contamination. Further, there is the risk that these compounds might be carried over into the biotic chain. In almost all countries, soil contamination is a generalized problem, which worries the different management bodies to a very great degree, depending on land use, there might also exist a threat to human health, the ecosystem, and underground waters (Cameselle et al. 2013; Falciglia et al. 2011; Swartjes et al. 2012). The possible resulting contaminated soils will be an obstacle to building activities, urban development, and the reuse of soils for other purposes, given that research and recovery works involve a large outlay of both time and money (Swartjes et al. 2012).

The main aim of contaminated land restoration is the lessening of negative impacts on people and the environment. Still, the restoration process may give rise to other effects, which, in their turn, might be positive or negative. For instance, remedial actions are normally associated with high costs, and environmental footprints, on occasion, have a greater reach than environmental risk reduction. On the other hand, restoration can give place to positive effects such as an increase in environmental quality and a recovery of the land for community use (Rosén et al. 2015).

4 Study Case: Energy Recovery of Petroleum Sulfonate Waste in an Environmental Protected Area

A successful case of environmental management is in the municipality of Arganda del Rey, in the Community of Madrid (Spain). From 1975 to 1992, the site was the site of an industry dedicated to the reprocessing of used oil. The environmental regulations of this remote period permitted the dumping of waste in what is now the Southeast Regional Park (Mora Peris et al. 2016). The pollution remains to this day in the form of acid ponds with an accumulation of organics of the sulfonic acid family, a petrochemical compound used for its surfactant properties.

The compounds of the family around sulfonic acid share the structure of H2SO4 except that one proton is replaced by an organic radical. Thus, there is chlorosulfonic acid with a chlorine atom in place of one of the two protons of H2SO4 or benzene sulfonic acid, with a benzene ring in place of one of the two protons of the inorganic acid. The asymmetry of having a proton and an organic functional group facing each other gives sulfonic acid surfactant properties. In its immiscible coexistence with water, it acidifies it toward low pHs, as well as decanting an organic phase.

The contaminated lake of Arganda del Rey has a surface area of approximately 13,000 m2 and accumulates 50,000 m3 of sulfonic acid loaded with heavy metals, mainly Pb and Zn, and Ba, Hg, Ni, and Va to a lesser extent. The contamination focus has decanted over time, where the sulfonic acid coexists with free water, heavier and lighter hydrocarbons, and a base of contaminated soil. The first of the decanted layers consists of a low-density oily phase 0.10 m thick. The second phase contains seasonally stagnant water with a load of dissolved contaminants. The third layer contains sulfonic acid and is the strongest, 5–7 m deep. It is black in color and highly viscous. The fourth layer consists of a non-pumpable solid phase with different speciations of heavy hydrocarbons, including polycyclic aromatics (PAHs), along with inorganic metals, sands, and gravel. Figure 1 shows a schematic of the different decanted layers.

Fig. 1
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Schematic of the different decanted layers

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The environmental problem was solved between 2015 and 2018 through its management by the Spanish cement sector, where the organic and metallic content were valorized to produce cement clinker. Just as the reduced state of the waste encloses carcinogenic and mutagenic affections, such chemical energy is releasable in an aseptic way in oxidation with air at high temperatures. The high energy dependence of CaCO3 calcination on coke enables cofiring with waste fuels, such as reprocessed sulfonic acid once neutralized. The high flame temperature (approximately 1500 °C) favors the kinetics of cleavage of the organic bonds to their oxides. Likewise, the metals react at high temperatures with the silica in the clinker recipe to generate complex silicates that promote setting in the final use.

Figure 2 shows the contaminated lagoon in the Community of Madrid where processing takes place and is then distributed to the nine cement plants also geolocated. On-site management of the different pumpable phases of the lagoon consisted of evaporative dewatering, homogenization, acidity neutralization with KOH, and truck transport to the nine Spanish cement plants. Neutralization generates neutral sulfonate with a pH compatible with cement rotary kilns. Evaporating occurs in a series of stages in which saturation temperature decreases as an effect of vacuum. The latent heat of condensation is used subsequently, at the energy cost of a primal energy input. Also, the environmental campaigns were carried out in summer to take advantage of stationary evaporation. The resulting fraction of solids is taken to a process of thermal desorption of organic contamination before its final deposition in a landfill. Table 1 shows the material and energy properties of each of the pumpable stratifications. Figure 3 shows and schematic diagram of the processing of both pumpable and non-pumpable fractions. Figure 4 shows the shares of fuel among the nine domestic cement plants.

Fig. 2
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Logistical nodes for transporting reprocessed fuel from Arganda del Rey to the nine cement plants

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Table 1 Composition of the pumpable layers (Mora Peris et al. 2021)
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Fig. 3
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Schematic diagram of the processing of both pumpable and non-pumpable fractions

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Fig. 4
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Shares of fuel among the nine domestic cement plants (Mora Peris et al. 2021)

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Just as the reprocessed fuel specifications at the entrance of the rotary kiln complied with sectoral regulations, the Boca Alta Park can now be restored for public use (see Fig. 5).

Fig. 5
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Final ecological restoration layout

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