*4.1.1 Recycling of industrial waste*

Waste recycling, also called beneficial waste usage, involves reusing waste materials generated from industrial processes to produce same or completely different finished products [22]. This has the advantage of reducing the need for producing too many new items and, in turn, reduces disposal at landfills which ultimately is beneficial to the environment [23]. There are a lot of opportunities for waste recycling in the industry and some wastes produced can be reused for road construction and repair, bridge construction, production of consumer goods, etc. [22]. Common recyclable industrial solid waste materials are coal combustion products, demolition and construction materials (**Figure 7**), scrap tires, and foundry sand [22]. Some of the reasons for recycling wastes by any industry are as follows: to reduce carbon footprint and conserve resources, to earn and save money, to save resources and energy when recycling machines are used, to reduce overall disposal cost, to improve company's reputation and create job opportunities and to build brand as ecofriendly, etc.
