Tag Archives: NOx

Mining3 makes emulsion breakthrough on alternative explosives project

In November, Mining3 says it achieved a significant milestone with the successful detonation of a world first hydrogen peroxide-based emulsion explosive as part of its alternative explosives project.

Using proprietary formulations, a series of trial blasts confirmed its ability to detonate, and provided early steps into the characterisation of this improved product, Mining3 said. “The new formulation is a major achievement in superseding water-gel/hydrogel formulations and a crucial advancement in product stability and sleep-time,” the company said.

Mining3 and the School of Mechanical and Mining Engineering at the University of Queensland are testing alternative explosive formulations, which eliminate the nitrogen component and replace it with hydrogen peroxide as the main oxidising agent. By removing the nitrogen component of the explosive formulation, it eliminates any NOx fumes generated after blasting, the partners said.

Back in January, Mining3 reported that detonation performance tests, conducted in December 2018 using new materials in the formula – physical sensitisation materials based on glass and polystyrene materials – had delivered improved explosive performance, reliability and product stability.

In its latest report, Mining3 reported on its emulsion developments: “Gums and emulsifiers, are the binding agents in water-gel and emulsions, respectively. Importantly, gums have a low-level organic contamination which leads to hydrogen peroxide degradation and limited current water-gel technology for manufacture-and-immediate-detonation applications.

“With synthetically produced emulsifiers, the material can be inert-to-hydrogen peroxide, lengthening the product stability to a significant period and enabling broader applications in the mining industry.”

Considerable effort has been invested in the pursuit of compatible emulsifiers, Mining3 said, and, with recent successes in detonation trials, it has made the past year of research “worthwhile”.

It continued: “Not only do we have a formulation with advanced oxidiser/fuel intimacy but also considerable advances in stability. Manufacture techniques have also maintained the ambient temperature methodology that gives the hydrogen peroxide-based explosives technology a distinct advantage in production cost.”

Over five days at RUREX, Australia’s only professional independent detonation testing range, upwards of 60 detonation tests were fired. Several other formulations were tested that will advance in the technology pipeline, but it is the confirmation of emulsion tests that was the most immediate success, according to Mining3.

This research has been supported by ACARP from its inception and transfer of this technology to the industry is eagerly anticipated, Mining3 added.

Dr Andrew Kettle, Senior Experimental Scientist and Project Executor, said: “These blasts have confirmed that we are pursuing the right pathway forward. We have invigorated enthusiasm going forward to further characterise the new emulsions in preparation for mine site trials in 2020. We are indebted, of course, to the ongoing support of ACARP and RUREX, and the vision of Mining3.”

CO2 Solutions, COAL21 see promise in enzymatic technology for carbon capture

CO2 Solutions and COAL21 Ltd say tests of CO2’s enzymatic technology have indicated that the process could be applied to coal-fired power plants for post-combustion carbon capture.

CO2 is a company focused on enzyme-enabled carbon capture, while COAL21 operates the COAL21 Fund to support the pre-commercial demonstration of low emission coal technologies (such as carbon capture and geological storage).

The technology developed by CO2, according to the company, lowers the cost barrier to carbon capture, utilisation and sequestration (CCUS), positioning it as a viable CO2 mitigation tool, as well as enabling industry to derive profitable new products from these emissions. The company has built an extensive patent portfolio covering the use of carbonic anhydrase, or analogues thereof, for the efficient post-combustion capture of carbon dioxide with low-energy aqueous solvents.

A study, conducted over the past 18 months by PROCOM Consultants, examined the performance of CO2’s enzymatic technology when applied to coal-fired power plants for post-combustion carbon capture. The methodology applied by PROCOM in this study included the development of rate-based models for absorber/stripper, the validation of the enzymatic technology’s heat/mass balance and the key performance parameters and model integration of the enzymatic technology in coal-fired power plants.

The simulation software used was Aspen Plus, with two reference cases modelled US DoE SC reference case (B12B) and a Supercritical (SC) power plant from Queensland, Australia.

In both cases, the performance of the CO2’s enzymatic technology was compared to a known advanced amine technology (Cansolv). CO2 provided two unoptimised process books of its enzymatic technology at different scales based on its ProTreat® models to the PROCOM study.

The main study conclusions reached by PROCOM Consultants, according to the companies, include:

  • The enzymatic technology appears well suited to coal-based industrial plants (eg iron and steel, cement) in particular for its tolerance to the oxides in flue gas and appears to have significant environmental and operational advantages over alternative post-combustion capture technologies, such as advanced amine technology;
  • By using low-grade, residual thermal energy in the form of hot water, the modelled unoptimised enzymatic solvent performance yields marginally more electricity in the context of an existing coal-fired power plant in Australia compared with the advanced amine process.
  • The enzymatic technology’s tolerance to SOx and NOx contaminants in the flue gas of low-sulphur coal-fired plants provides it with an estimated 30% capital expenditure (capex) advantage relative to the advanced amine technology since there is no requirement to polish this flue gas down to single digit parts per million using Flue Gas Desulphurisation and Selective Catalytic Reduction;
  • Modelling has confirmed that SC coal-fired power plants in Australia have sufficient residual low-grade heat to give the enzymatic technology a slight power efficiency advantage over the advanced amine technology. Moreover, the likely further optimisation of the enzymatic technology would extend this advantage.
  • In addition to being able to use residual, low-grade heat in the form of hot water as its thermal energy, the enzymatic technology could also tap into renewable energy sources such as geothermal and solar thermal sources for its energy requirements, options which are more challenging to the advanced amine technology which requires steam, according to the companies. Tapping into these sources of external renewable heat would potentially significantly reduce the thermal parasitic load of carbon capture;
  • The PROCOM study confirmed the enzymatic process minimises the environmental footprint through the use of an ionic (non-volatile) and environmentally benign solvent;
  • The enzymatic technology converts a portion of the oxide contaminants in the flue gas (SOx and NOx) into high-value sulphates, sulphites, nitrates and nitrites, which accumulate over time in the solvent. As a result, the periodic bleed of this nontoxic solvent creates an opportunity to recover valuable materials, such as potassium nitrate fertiliser, which reduces the overall operating cost of the enzymatic technology. This approach is not available to the advanced amine technology, and;
  • Through expected optimisation, the enzymatic technology could be more favourable than amine-based processes regarding capex and overall energy requirements, and very favourable to amine-based processes regarding aspects related to management of oxide flue gas contaminants.

Richard Surprenant, CO2 Solutions’ Chief Technology Officer, said: “The detailed report prepared by Procom Consultants highlights the low-cost and environmentally friendly qualities of our process. It further confirms the major paradigm shift that the enzymatic technology represents for the carbon capture industry.

“We strongly believe that the future of carbon capture rests on modern, innovative, low environmental footprint, and low-cost technologies. It’s time to face today’s carbon challenge with 21st-century technology.”

Mark McCallum, CEO of COAL21, said the enzymatic technology developed by CO2 Solutions is an “exciting process that holds the promise of lower-cost and environmentally friendly carbon capture”.

He added: “It has demonstrated that it is possible to reduce parasitic energy loads and the overall environmental footprint. It is through the broad application of technologies such as these that we can mitigate carbon emissions from any source, including coal.”

Cat 797F haul truck proves its worth in Tier 4 Final configuration

Cat says its 797F large mining truck is now available in a fuel-efficient configuration that meets US EPA Tier 4 Final emissions standards.

Through more than 16,000 hours of successful pilot machine operation and 100,000 hours of production truck operation in Tier 4 configuration, the system has proven its ability to deliver strong performance and greater fuel efficiency compared to the Tier 2 797F in most applications, the company said.

The 797F Tier 4 Final is equipped with an exhaust aftertreatment system featuring selective catalytic reduction, which uses diesel exhaust fluid (DEF) to lower NOx emissions. This Cat emissions platform is proven through more than 20 million operating hours in the field, according to the company.

The 797F aftertreatment system uses less than 11% new content, improving reliability, while the modular aftertreatment system, with readily accessible components designed for serviceability, is aligned with truck preventive maintenance intervals to maintain high availability, Cat said.

The best-selling truck in the 400-ton (363-t) size class, according to Cat, the 797F is powered by a 4,000-hp (2 983-kW) Cat® C175-20 engine, available with optimised fuel maps for customers focused on the lowest fuel burn, Tier 2 equivalent rating, and now Tier 4 Final. It is renowned for delivering class-leading payload and speed-on-grade performance, Cat said, adding that the 797F delivers the same production performance in Tier 2 and Tier 4 Final configurations.

“Beyond offering similar performance, the Tier 4 Final 797F reduces total specific fluid consumption costs (fuel plus DEF) in most applications,” Cat said. “Lower fuel burn results in longer engine life and lower repair costs.”

Field evaluations of the 797F included a wide range of applications in oil sands, deep pit copper, iron ore and coal mines. The trucks exceeded production targets and demonstrated strong engine performance in all applications, including sites with extreme ambient temperatures as well as some with altitudes greater than 16,000 ft (4,877 m), according to Cat.