A textile manufacturing plant in Spain’s Basque region has been using Rolls-Royce technology as the base of its CHP system since 1995. The latest pair of engines operate at availabilities of 95%, helping the CHP plant meets the factory’s entire energy requirement.

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Interior of the textile production plant next to the Leizarán River

San Sebastian, perched on Spain’s northern coast, is one of the country’s most beautiful cities. To its south lies a bucolic landscape of verdant hillsides, thick woods and caseríos, the typical rural houses found throughout the Basque Country. Industrial activities of all descriptions dot the landscape along with modern residential areas.

Cutting-edge technology is also here amid the picturesque legacy of a rich history. In nearby Andoain, for instance, the Inquitex chemical and textile production plant runs a high efficiency cogeneration plant that supplies the factory’s entire requirement for electricity, heat, hot water, cooling and steam.

Inquitex is the Spanish Basque Country’s only synthetic fibre manufacturer, located close to where the road that crosses the Basque Country meets those to Navarre and central Spain. Its founders, back in 1952, were drawn to the bank of the Leizarán River, which provides the ideal water quality for synthetic fibre production.

The company’s products include two kinds of polyamide products – staple fibre since 1954 and textile yarn since 1960. Inquitex branched into polypropylene fibre in 1980 and into polyester staple and PET sheet fibre in the 1990s, when it also installed a recycling system for by-products.

Inquitex currently has two main product lines, polyester fibre and PET laminate. Its polyamide fibre is used in the textile industry and also in non-woven fabric for hygiene and cleaning products. In addition, the firm is making major advances in imitation natural and animal fibres such as silk, mohair, angora and fur. The company’s polyester fibre is used by many major car manufacturers and also in the hygiene industry.

The second line is PET sheet, which has a wide range of thermoforming applications in the food, printing, cosmetic and pharmaceutical industries, as well as in industrial processes. The company is known for its service, quality and flexibility in developing new products, with a polyester pilot product line that produces new colours in short time frames.

Inquitex exports two thirds of its production, mainly to western Europe, including the UK, France and Germany. It is now focusing on expansion into central and eastern Europe, especially the Czech Republic.

ON-SITE CHP SYSTEM PROTECTS POWER QUALITY

To compete successfully in Europe, Inquitex had to offer added value. To ensure this, it complies with the strictest quality and environmental regulations. The company has increased the amount of recycled materials in its products, so that its recycling containers take in the equivalent of one in every three PET bottles discarded in Spain.

For an efficient, safe and environment-friendly supply of electricity, heat and cooling, Inquitex relies on an on-site combined, heat, power and cooling plant powered by a pair of Rolls-Royce gas engines. Security of supply is essential to synthetic fibre manufacturers, as transient voltage or current micro-cuts can affect the quality of the fibre. Inquitex therefore saw an independent power source as the only way to avert such problems.

In the early 1990s, when the first natural gas cogeneration plants were being built in Spain, Inquitex decided to install one of its own. At first, few people in Inquitex were convinced of the need for an independent power production system. In 1995, though, the first Rolls-Royce Bergen KVGS 3 MW engine was installed. Its results far exceeded expectations and, three years later, a new Rolls-Royce engine was brought in.

Inquitex originally chose Rolls-Royce Bergen engines because they were used by the casing manufacturer Viscofan, whose plant was the first in Spain to install Bergen engines. The firm was further convinced by a report from Cadem – the Basque government agency for energy development – that recommended this type of natural gas engine.

The cogeneration plant meets the factory’s total power demand, and more. Strictly speaking, it is a trigeneration facility, as it has a cooling machine, based on an absorption cycle that uses the waste heat from the gas engines as the primary power source to supply chilled water for the air conditioning system and other purposes.

The output of steam and hot water is used in production processes as needed. Electricity in excess of the factory’s requirements is fed to the power grid. The plant has an overall efficiency of 75%.

NEW LEAN-BURN ENGINES TAKE OVER

When its engines had accumulated 84,000 and 61,000 running hours respectively, Inquitex decided to replace them with two Rolls-Royce units from the B35:40V AG series, each with a power rating of 5.1 MW. The B-gas engine is a medium-speed, spark-ignited, lean-burn machine designed to produce up to 8.5 MW of electrical power, and to give customers more energy and greater cost effectiveness than its competitors.

The design was driven by stringent requirements for lower exhaust emissions and maximum electrical and heat recovery efficiency, coupled with extreme reliability. Decisive features are the enlarged cylinder volume and optimized combustion technology, which ensures top performance without over stressing.

Inquitex stuck with Rolls-Royce because of its positive experience with the earlier engines and its need for guaranteed reliability, as well as advice from a private consultant and the company’s aftermarket service. Over the years, Inquitex has borne witness to Rolls-Royce’s business development in Spain and the steady advances in its products and services.

In their first month in operation, the new engines attained availabilities of 94% and 96% – and today high engine efficiency and total reliability are fundamental. With gas consumption equal to half of that of the provincial capital, San Sebastian, Inquitex has entered a new stage in its history with big challenges and ambitious goals, and is firmly focused on reaching the highest energy efficiency and the best performance.


 

Rolls-Royce engines power Spanish sludge-drying plant

High-efficiency Rolls-Royce gas engines now power a major new sludge-drying plant in Spain, which is aiming to become one of the most effective plants of its kind in the world.

The cogeneration plant at Loeches on the outskirts of Madrid has three Rolls-Royce B35:40 V16AG engines, each with 6.6 MW installed capacity, operating two thermal drying lines. Big enough to process most of the sludge from Madrid’s water treatment plants, the facility will exploit the Rolls-Royce power units’ 46.4% electrical efficiency – the highest available from any gas engine on the market – to treat 155,000 tonnes of sludge each year.

‘The efficiency and heat output of these B35:40 gas engines gives the Loeches plant high energy efficiency while saving energy at a global level and reducing carbon dioxide emissions to the atmosphere,’ says Carlos Prieto, managing director of Rolls-Royce Marine Espana.

Some two-thirds of the plant’s annual through-put will undergo thermal drying with the remainder used for composting. The compost is derived from a mixture of dried sludge and plant-trimming remains and is suitable for use in agriculture, landscaping re-generation and gardening.

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