Passing “End of Waste” and CO2e removal tests

23 July 2021
Posted in News
23 July 2021 sg-admin

Laurence Sharrock, Standard Gas’s technology guru, has played a central role in transitioning the company’s energy-from-waste process from demonstration plant to the significantly upgraded and upscaled commercial SG100 unit currently in manufacturing phase. Having been a prime mover in gaining industry-leading “End of Waste” accreditation for the technology, Laurence is now leading the line with Standard Gas’s engineering design and manufacturing partners and flying the flag for the SG100’s carbon-negative energy generation and carbon-removing capabilities.

Standard Gas’s Technical Director, Laurence Sharrock, first encountered the company when he was contracted to undertake emissions testing on the SG50 demonstration plant located at Huntingdon, UK. “I was really struck by the plant’s capabilities,” he recalls. “It was so compact size-wise compared with the huge incinerators and other facilities where I’d tested. But the cleanliness of its syngas and its energy-generating potential, and, significantly, the absence of any harmful emissions were real stand-outs. Later, as we developed the technology, we realised its carbon-removal potential.”

At the time, Laurence was a senior manager with Environmental Scientifics Group, the UK’s leading UK Accreditation Service and Monitoring Certification Scheme accredited testing, inspection, certification and compliance company. Intrigued and impressed with what he’d seen at Huntingdon, in 2013 Laurence was persuaded to join Standard Gas. Today, after 8 years with the company, he is responsible for technology development and delivery, which includes engineering, certification, compliance, permitting and commercialisation

Commenting on Laurence’s contribution to the company, David Whitmarsh, Standard Gas’s chief executive, says: “He has an encyclopaedic knowledge of the parts, processes, inputs and outputs of the SG100 having worked hand-in-glove with the engineering design team at Swift Technology Group as we upgraded from the SG50 demonstration plant. Together, they’ve developed the SG100, which is easier to build, has significantly enhanced performance metrics, and has raised processing capacity to 48,000 tonnes a year. On top of that, they’ve improved accessibility for production, maintenance and repair. The value Laurence has brought to the company is immense.”

Back in 2015, Laurence played a key role in the initiative that led to Standard Gas receiving the UK Environment Agency’s “End of Waste” (EoW) certification for its syngas. “What EoW means is that our technology has demonstrated on a range of wastes that the syngas produced is comparable in cleanliness to natural gas,” he says. “Testing for this was in-depth and independently verified by UKAS-accredited test houses with accompanying analysis by a UKAS laboratory. EoW accreditation also means that our technology is not subject to the regulatory requirements of the Waste Incineration and Waste Co-incineration/Industrial Emissions Directive. So – when suitably coded – waste processed in our plant is at the end of its lifecycle as a ‘waste’, and becomes a valuable, tradeable product. In our case, that means syngas for electricity generation, or for renewable transport fuels or grid injection, and char for industrial or agricultural products among other end-uses.”

Laurence adds: “Standard Gas technology is essentially a manufacturing process for clean energy and carbon-removing char. And because we’re not burning or combusting waste in our process, and the treated output gas is incredibly clean, planning and permitting are straightforward. Based on my industry experience and what’s out there in the market, I’m convinced there’s no cleaner route for the disposal of waste and production of energy and char than our technology.”

A modular unit – about the size of a tennis court and high as a house – the SG100 comprises five core systems designed for simplicity in construction and installation. “Its’ ingenuity lies in an ability to rapidly heat waste, producing a char and a syngas, and then crack the syngas into smaller molecules, thereby preventing tar build-up and preserving the waste’s inherent calorific value. The syngas can be directly used in local reciprocating engines to generate electricity or processed into pure methane suitable for gas grid injection, a renewable transport fuel, and potentially chemical feedstock. With electrolysis, the electricity can also be used to generate hydrogen,” Laurence says.

SG100 char is a mixture of pure carbon and ash, depending on the type of waste used. “As the SG100 can process a wide range of waste types – from fully biogenic wastes to mixed wastes such as RDFs, and from fossil-derived plastics to some hazardous wastes – the percentage of carbon in the char varies from 97% to 70%,” Laurence explains. “An ISO-14064 compliant process analysis* found the SG100 is highly carbon-negative when running on a biogenic feedstock because the char – or biochar – more than offsets any emissions from the waste’s fossil fraction and the general industrial process, both of which are very low. For every 48,000 tonnes of biogenic waste processed, the analysis found that the net negative CO2e for each plant was in the order of 16,000 tonnes. That’s a tangible amount of GHG emissions caused by human activity. Being biogenic, this char can be easily sequestered without the additional removal costs required for gaseous forms of carbon.

“What’s more, this analysis found that even with high fossil fractions in the waste, the replacement savings of CO2e from this waste not having to be landfilled or incinerated were considerable. As the technology produces a clean syngas, its combustion in the production of electricity is both less emitting and more energy-efficient than incinerating the waste. That’s because the calorific value of waste burnt in an incinerator can only be captured via boilers, which produce steam to drive turbine generators. For every 48,000 tonnes of fossil-derived waste processed, the SG100’s net CO2e saving compared with incineration (with electricity production) was calculated to be c.25,000 tonnes.”

(* Analysis findings have been verified by Dr C. Meinrenken, research scientist at Columbia University’s Earth Institute, and, separately, by South Pole a leading environmental consultancy. Commenting on the SG100, Dr Meinrenken stated: “Given the size of this [biogenic] fraction, this can render Standard Gas’ process overall carbon negative and likewise its products, namely electricity, recycled natural gas, or waste heat, carbon negative. Such accounting would be in accordance with the applicable accounting standards and protocols for assessing enterprise and product life cycle carbon emissions, including those from and the International Standards Organization (ISO).” Work undertaken by South Pole has confirmed that the SG100 complies with a wide range of not-for-profit organisations’ requirements for carbon credits. This will enable those adopting the technology to integrate the SG100’s carbon status into their efforts to achieve Net-Zero status.)