How to increase max active connection limits from default 520.
System configuration CentOS release 5.8 (Final) with whm.

nginx conf file is

user nginx root;
worker_processes 16;
worker_rlimit_nofile 200000;
worker_connections 10240;
error_log /var/log/nginx/error.log;
error_log /var/log/nginx/error.log notice;
error_log /var/log/nginx/error.log info;
pid /var/run/nginx.pid;
events { worker_connections 10240; use epoll; }
http { include /etc/nginx/mime.types; default_type application/octet-stream; index index.php index.htm index.html; log_format main '$remote_addr - $remote_user [$time_local] "$request" ' '$status $body_bytes_sent "$http_referer" ' '"$http_user_agent" "$http_x_forwarded_for"';
access_log off;

sendfile on;
tcp_nopush on;
tcp_nodelay on;
server_tokens off;
gzip on;
gzip_static on;
gzip_comp_level 5;
gzip_min_length 10240;
keepalive_timeout 30;
keepalive_requests 100000;
limit_conn_zone $binary_remote_addr zone=addr:10m;

include /etc/nginx/conf.d/*.conf;
server {
limit_conn addr 20000;
listen 7007;
server_name _;
root /usr/share/nginx/html;
location / {
root /usr/share/nginx/html;
index index.html index.htm;
}

error_page 404 /404.html;

location = /404.html {
root /usr/share/nginx/html;
}
location /favicon.ico {
empty_gif;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
location ~ \.php$ {
root /usr/share/nginx/html;
fastcgi_pass unix:/tmp/php.sock;
fastcgi_index index.php;
fastcgi_send_timeout 8m;
fastcgi_read_timeout 8m;
fastcgi_connect_timeout 8m;
include /etc/nginx/fastcgi.conf;
}

location /status {
stub_status on;
access_log off;
}
} }

/proc/sys/net/ipv4/ip_local_port_range 9000 65535
/proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_timeout_time_wait 1

If any other information need pls tell me.
I am not able to find where I have to set max active connection limit for nginx in the conf.