Biological reduction of nitrate to nitric oxide, nitrousoxide, and nitrogen gas. Involves both nitrification and denitrification. Biological nitrogen removal (BNR) is more cost effective and used more often as compared to ammonia stripping, breakpoint chlorination and ion exchange; BNR is used in wastewater treatment where: there are concerns for eutrophication;

Total concentration of organic and ammonia nitrogen in municipal wastewater in the range 25‐ 45 mg/L as nitrogen based on flowrate of 450 L/capita.d (120 gal/capita.d). With limited water supplies, total nitrogen in excess of 200 mg/L as N measured in domestic wastewater. Drinking water maximum MCL for nitrate nitrogen is 45 mg/L as nitrate or 10

This test method is used to determine the amount of water required to prepare hydraulic cement pastes with normal consistency, as required for certain standard tests. The percentage amount of water which is required to prepare standard cement paste when vicat plunger penetrate under 10±1mm reading is known as standard consistency or normal consistency

Proportion the standard mortar using 350 g cement to 1400 g 20–30 standard sand and sufficient water to give a flow of 871⁄2 6 71⁄2 %. The flow is the resulting increase in average diameter of the mortar mass, as determined with the calipers, measured on at least four diameters at approximately equi-spaced intervals, expressed as a percentage of the original

To identify the classification to which any road belongs, the following factors should be considered: SERVICE FUNCTION:- Most roads provide service to traffic, access to land or both. Following road type provide the service function given as; Freeways and Arterials ==> provide the movement of through traffic. Local roads ==> are used almost exclusively for land