Applications

Latest situation

In the waste of households and industry, masses of gold and silver treasures are stored – in discarded electrical appliances. And there are plenty of them: 40 million tons of electronic devices end up on the garbage worldwide every year, according to a report of the UN environmental program Unep.

Current problem

The business with electronics recycling is becoming increasingly lucrative, reports the Bundesverband Sekundärstoffe und Entsorgung (BVSE). Many recycling companies have now settled in Europe. They have benefited from the high metal prices of recent years. However, the high costs of processing the metals are depressing their profits.

AGT solution

Conversion is the optimal solution for recycling electronic waste. Within the LTC process, the various materials (plastics, metals, minerals) are gently separated. The organic substances are converted and processed into a strong gas comparable to natural gas, while all metals and minerals, such as gold, platinum, rare earths, copper, etc., remain undamaged for reuse. The recycling of these treasures in landfills can be described as modern raw material mining – sustainability in its purest form.

Benefit

Even high production rates, as in the potassium gold mine in South Africa, where five grams per tonne of rock are extracted, have a pitiful effect on the treasures of mountains of rubbish: Christian Hagelüken of the recycling company Umicore in Brussels reports that millions of computer circuit boards containing 250 grams of gold per tonne lie there. With AGT’s low-temperature conversion (gasification), recycling is worthwhile because the costs of processing are significantly reduced and the yield is thus many times higher than with previous methods.  The average ROI of this type of plant naturally depends on the content of valuable metals, but is at most 4 years.

Latest Situation

Presently waste dumps are growing in every civilisation. Intended savings cannot be implemented. In terms of energy production, the combustion of waste is not profitable.

Current Problem

Old dumps are getting full, new dumps are hardly authorised any more. Waste is just stored; it putrefies and the gas that is created is burned off without being utilised. Noxious substances trickle away and must be collected and processed at high expenses.

AGT-Solution

Using the low temperature conversion process, it is possible, without too much expense for waste separation, to convert the mixed household waste into gas and use it for power generation. Heavy metals and other noxious substances are absorbed already in the plant and are either processed immediately or collected for recycling.

Benefit

The main advantages

• Useless waste becomes cheap energy.
• Closed system, no emission of noxious substances to the environment
• Small and profitable plants, since very expensive components needed for waste combustion facilities such as exhaust gas purification, slag stabilisation etc. are not required. The same is also true with regard to the running operating costs.
• Compared with the combustion plant, this system is 50% cheaper as regards investments, since far less building expenses are required.
• Compared with combustion, notably higher degree of efficiency of power generation due to a gas-steam turbine combination
• Cost-effective operation of the plant since, for instance, no additional energy for fuelling is required.

Latest Situation

Combustion is used for the disposal of sewage sludge, although the PE or lime-conditioned press cakes are – properly speaking – not suited for a combustion process. Pressed sewage sludge material has a water content of more than 60%.

Current Problem

Therefore, combustion works only following previous drying and/or with adequate support fire. However, in any case, energy consumption is so high that it is completely unrealistic to use sewage sludge combustion for a net power gain for appreciable power generation.

AGT-Solution

The situation is totally different with sewage sludge conversion. Naturally, here again 60% of the water content cannot be utilised as such, but in a reform step downstream in the conversion process proper, up to 40% of the water contained is refined to water gas which is used for integrated sludge drying.

The dried organic part contained in the sludge is then converted to strong gas and converted to current by means of gas and steam turbines. Since no thermal surplus is released with this concept, a power/heat coupling device is not provided.

For a net energy gain as high as possible it is decisive whether the converted sewage sludge is fermented sludge which naturally contains less carbon and thus provides less energy, or if it also contains fresh sludge ratios. In addition, also PE conditioning versus Ca addition leads to an increase of the energy yield.

Benefit

• The low temperatures of the conversion process do not lead to a reduction of heavy metals in ash/slag, therefore easy dumping of residual substances is ensured.
• The organic residual ratios in ash are below 5%, thus, dumping EU-wide is possible.
• Notably cheaper plant operation results from the continuously cheaper operating costs due to lower staff requirement, sludge drying due to exhaust heat and no additional support fire.

The conversion process facilitates a notably higher efficiency factor of current conversion due to the combination of gas and steam turbines. On the other hand, current sewage sludge combustion is only possible with steam turbines at a notably lower factor of efficiency. Due to the low exhaust heat production in the conversion process, there is a much lower and even negligible energy loss compared with the combustion process.

Utilization of locally available biomass e.g. loppings, wood cut or straw – even when polluted!

Latest Situation

Modern biomass power plants burn the heating material by means of fluidised bed technology. They heat up water and produce steam with which steam turbines are operated for current generation.

Current Problem

The technology used here was developed for fossil fuels with a double to triple thermal value. Just because of biomass quantities needed and the logistics required, an economic operation of caloric power plants is not possible without massive subsidies.

AGT-Solution

If, however, biomass is converted to medium and strong gas, combinations of gas/ steam turbines with a maximum efficiency factor can be operated. When using biomass fresh from the harvest, the quantity of specific power generation can be increased by approx. 100% to the double amount of conventional biomass power plants.

Here, the usual current-to-heat ratio of 1:2 is shifted to 2:1, in large-scale power plants the waste heat frequently being used to a limited degree only and not at all in summer. Additionally, biomass power plants, according to the conversion process, can be used for peak current generation since the converted gas quantities can be stored intermediately and called up selectively.

Benefit

The conversion technology for biomass power generation facilitates the world-wide use for a CO2-neutral current production at prime costs, in accordance with the market, due to simpler regulations for environmental protection, a considerably increased efficiency factor, and the higher economy resulting there from.

Latest Situation

Successful industries need cheap electric energy. However, more than 50% of current costs result from grid fees only. Thus, if the current required is produced directly at the consumer, these specific costs for grid transmission can be saved. Nor do the high connection and provision costs accumulate.

Current Problem

The costs for the fuel required are decisive for the production of an industry’s own current. Using modern, fully automatic gas generators every industrial company would be able to generate its own current needed, but the high natural gas costs represent an obstacle to the realisation of such considerations.

AGT-Solution

However, if liquid conversion gas is used for current conversion in separate conversion generators, a considerably higher energy content and at the same time moderately priced turbine fuel as compared to natural gas is achieved.

In the current conversion process, 10% more current is always automatically produced than is needed at a certain time by means of a variable turbine set. Delay controllers on major consumers prevent too many consumers from being connected at the same time which leads to black-outs. The surplus current not consumed is transmitted to the public grid which, in any case, continues to be available to cover the basic supply for lighting and control.

Benefit

• With this concept major current consumers, such as producers of machine lines, production lines, presses, furnaces etc. can be operated with company-generated current which is much cheaper.
• The CO₂-quantities saved in power generation of the biomass liquid gas can be credited or sold.
• Energy-intensive companies can be established and operated irrespective of the regional supply (overground and underground construction, mining, tunnel construction, quarries, etc.). Furthermore, existing energy consumers can also be switched over to environmentally neutral current operation.
• With this bio liquid gas forklifts, loading tractors, trucks etc. can also be operated, thus saving the environment.
• Adequate pricing makes it possible for the companies to buy and lease the conversion generators or just to purchase the current produced with them.

Cryogen-granulation und power generation within one plant!

Latest Situation

Various mechanical engineering and plant construction companies have developed tyre crushing plants which facilitate the easy exploitation of pure tyre rubber substrate. Using such plants, huge quantities of used tyres can be processed quickly and at moderate prices.

Current Problem

Increasingly, the large volumes cannot be processed any more in recycling products and combustion, the method practised up to now, is limited by law. Therefore, there is an urgent need to search for innovative solutions to the problem.

AGT-Solution

Conversion is the optimum solution for generating energy from tyre granules. During the process of tyre granule conversion to gain energy, the reusable components are released, withdrawn, stored intermediately and subsequently linked in a way so that the energy content released is available in a synthetic strong gas.

In the tightly closed process that takes place without producing any waste gas, the valuable organic components from the benzol and butane derivatives can be processed into a strong gas comparable to natural gas which is then converted into electricity with maximum efficiency in a combined gas and steam turbine. For process reasons the operation of the gas turbine is an integral part of the plant and designed for the ongoing process. However, since the turbine can also be operated under a partial load, the surplus conversion gas, stored intermediately in external reservoirs, can be used for the production of peak current.

Benefit

It is only due to the conversion of used tyre granule that an economical current conversion of major quantities of crushed tyres is possible any time. Since the electric power thus produced can be easily supplied to the grid, this process circumvents the sales problems for tyre granules which otherwise would appear quickly.

Thus, used tyre granule conversion is a new and innovative process, according to EU specifications for recycling used tyres, to gain energy with a very high degree of efficiency. The average ROI with this type of plant is approx. 3-4 years.