Interview: Waste to watts
While engineers across the globe continue to remain obsessed with the idea of providing cooler, cleaner and greener power as well as energy solutions, there are those who are striving to extract every ounce of energy from the heat that is lost in power generation and thermal systems. Waste heat recovery methods used in industrial plants utilise the heat that would otherwise dissipate into the atmosphere.
Engineers in Pakistan, despite prevailing constraints, continue to forge ahead to provide indigenous engineering solutions for achieving efficient utilisation of heat loss from power plants. One such self-made engineer-entrepreneur is Sajjad Ghani, CEO of a local industry, a graduate in mechanical engineering from San Luis Obispo, CA USA, who has struggled to carve a niche in the field of steam boilers, plate heat exchangers and custom-designed industrial waste heat recovery systems.
The following are the excerpts form an interview with him:
How important is to deploy waste heat recovery devices in a country like ours? What are the benefits that can be accrued from such ventures?
The state of ubiquitous energy deficit needs no explanation. In any generation plant or an automobile engine, the useable energy output is barely 30 to 35 per cent. The rest of the energy is expended through the water-cooled jacket, a radiator and the exhaust pipe. As a result almost 70 per cent of the fuel is being wasted. Considering the number of similar plants in operation countrywide, the losses would run into billions.
What made you enter into the field of waste heat recovery?
After my graduation I worked in the United Arab Emirates for about a decade, with a building services mechanical contractor. There I gathered experience through practical installation of building services in accordance with universal standards and stringent quality. This grooming became my asset which, combined with my fetish for thermodynamics, transformed me into a passionate designer and systematic implementer. On return from the UAE, I began technical design of heat recovery systems and components by manufacturing a central heating boiler for a client in Lahore.
At what juncture of your career did you feel that this was the breakthrough that you had been waiting for?
During the mid ’90s, the government allowed industries to generate their own power with a small requirement of recovery arrangement, which initially nobody followed. Subsequently, a renowned textile mill gave me my first major breakthrough. To this day I admire the competency of the client’s consultants and the engineering staff who had the vision and were able to appreciate my concept of co-generation or I should say tri-generation. This mutual trust led us to design an efficient system of obtaining air conditioning and steam generation from their four MW power generation system.
This was the first time ever that engine jacket heat was used for refrigeration purposes by firing absorption chillers with the hot water giving 400 tonnes of refrigeration. As a result, the engine manufacturers were also able to sell numerous units because of our recovery design around it. The exhaust at 500 deg C was used in waste heat recovery boilers resulting in 3.6 tonnes of steam at 10 bar pressure. This project, with a 70 per cent indigenous component, became a gateway for a barrage of orders that followed.
What are the standards that you currently adhere to? Do you have any third party independent checks for safety, security and quality?
We comply with the ASME standards and have third party inspections being fully aware of the safety and efficiency implications. We have a system of design certification from Lloyds of the UK who also delegate their representatives for on-site inspections to endorse stamps of approval. The boiler board of the ministry of industries also granted us license after verifying performance of products.
Does the government extend any assistance or tax rebates to encourage the line of manufacture that you are in?
The government protects the local industry and is supportive of indigenous manufacture. It provides not only exemption on sales tax to avoid double-taxation, but also charges reduced duties to certain recognised manufacturers. Once the unit has been fabricated then the sales tax is charged at the time of sale. However, there are some traders who try to import similar items and sell them without the sales tax at a price which is 17 to 20 per cent lower than ours. This upsets the entire process of self-reliance and the initiatives of government to curb the depletion of foreign exchange.
Do you think that you have an adequate market for the products that you fabricate despite the constraints and trading anomalies?
We get orders primarily for our engineering design and complete turnkey solutions which include the crucial element of responsibility and commitment. Our advantage, however, remains limited due to the competitors who tend to avoid duties and sales tax since the local industrialist wants to pay the least. This also affects employment opportunities for skilled and unskilled labour adversely.
What are the areas of production that you are longing to venture into considering the necessity to conserve energy?
There is a great deal of work that needs to done in this area but given the sombre nature of the research required, I would certainly have to be selective. With our country lying on warm latitude, exploiting solar heating seems to be the obvious choice. I am seriously looking at solar water thermal venture using parabolic arrangements.